Abdullah, Yehia, Al Ezz Dekheila Steel Co., Egypt

Co-Author: Ashraf Khamis Ismail, Al Ezz Dekheila Steel Co. • Hossam Eldin Hamdy Abdelmeguid, Al Ezz Dekheila Steel Co.

Abstract: EZDK Flat Steel Plant (FSP) installed in Y1999 consisting of steel making SMP (1 arc furnace EAF,1 Ladle furnace LMF) and compact strip plant CSP (thin slab caster TSC, hot strip mill HSM), plant design capacity 1.0 MTPY HRC producing low Carbon, different ranges of Mn steel grades, Aluminum killed clean steel, thickness 1.0~14 mm, widths 900~1600mm. Aiming reaching 1.150 MTPY HRC, defining such one FSP line production bottle neck is mandatory especially after CSP upgrading in Y2017 after increasing TSC casting speeds for different casting widths So, SMP(EAF) is identified as the bottle neck due to prolong tap-tap time TTT (56 min./heat), high EAF energy consumption (575 kWh/t MS) which limit productivity at higher casting speed (>4.5 m/min.) for 1500 mm casting width. Decreasing EAF power on time, energy consumption (productivity driven factors) are put as a target which can be achieved by introducing new chemical energy modules for C-O in EAF with low project budget keeping the rest of EAF configuration such as transformer as increasing transformer capacity ‘increasing input electrical power ‘will require consecutive additional changes in EAF upper& lower shell, fume extraction system with huge investment budget. An Italian company ‘MORE’ offered a new module of C-O in EAF called ‘M-One’ which has the feature of Carbon, Oxygen & natural gas injection in one coherent jet giving higher efficiency of reaction points between C-O with equal uniform distribution of slag foaming around EAF, giving better Oxygen penetration into molten steel giving higher slag foaming index moreover, burner mode of M-One enables faster scrap melting time. After successful installation & commissioning of M-One in Nov.Y2022, very promising results are obtained in productivity (+5%), power on time (-11%), turnaround time (-15%), Tap-Tap time (-12%), energy consumption (-11%), C injection consumption (-30%), EAF electrode consumption (-8%) and EAF refractory consumption (-12%).

Adachi, Takero, KOBE STEEL, LTD. , Japan

Co-Author: Johannes Schenk, Montanuniversität Leoben • Daniel Spreitzer, Montanuniversität Leoben

Abstract: Fluidized bed reduction technology is one of the items in carbon neutral ironmaking because of its flexible gas input and no need for agglomeration which leads to environmental friendliness. In the case where fluidized bed reduction system is installed in an integrated steel plant, partial substitution of blast furnace ironmaking and CO2 reduction are achieved by using exhaust gas such as coke oven gas as reductant. Moreover, it helps operation of agglomeration process by using unsuitable types of ore that lowers agglomeration productivity. Hence, fluidized bed installation into steel plants is not only the possibility of hydrogen-based carbon neutral technology but also bridge technology in CO2 reduction road. A scheme of multiple fluidized bed system design for an integrated steel plant involved with mass- and heat-balance calculation has been established in former research. However, unique characteristics of ore such as dense structure or iron-bearing complex oxide formation disturb reduction reaction. Especially, the latter case is observed in using blast furnace grade ore for fluidized bed reactor. In this study, two countermeasures to increase reduction degree are proposed and evaluated experimentally. One is elimination of hematite to magnetite reduction stage to avoid structure densification. Cross sectional observation of the reduced sub-samples collected after each stage shows porous structure is formed by the countermeasure. The other is dividing first reactor into two to decrease gas oxidation degree in metallization stage. Thermodynamical study by FactSageTM reveals that required gas oxidation degree for reduction of iron-bearing complex oxide is quite low compared to reduction of pure wustite to metallic iron. These countermeasures provide increase of final reduction degree in fluidized bed reduction experiments using 160 mm inner diameter furnace.

Dr. Adam, Henrik, Chairman of Steel Institute VDEh, Vice President European Corporate Affairs of Tata Steel, Tata Steel Ltd, Netherlands

Abstract: Welcome address of the host

Adam, Jörg, VDEh-Betriebsforschungsinstitut GmbH, Germany

Co-Author: Christoph Thaler, voestalpine AG • Ramona Eßbichl, voestalpine AG • Christian Rittenschober, voestalpine AG • Andrej Johnen, thyssenkrupp Steel Europe AG

Abstract: The damage of a blast furnace tuyere is an unpredictable incident, happening in average between 30 and 100 times a year. As a result, two hours, in some cases up to eight hours shut down are necessary to change such cooling elements. Production loss, extra coke and steam for shut down increase the costs of hot metal (HM) production. Unplanned stoppages due to damages at the blast furnace tuyeres also cause additional emissions like CO2 etc. In the last decade BFI, in cooperation with various national and international partners, developed innovative systems for the observation of BF tuyere operation and the protection of BF tuyeres. The objectives were to generate advanced knowledge about tuyere damage mechanisms by the development of innovative systems for the monitoring of BF tuyeres during operation and to point out measures to extend BF tuyere operating life. The presentation will focus on:  BF measuring tuyeres with fibre optical temperature measurement  Optical monitoring system The presentation gives an overview about the investigations, findings and results of different national and international projects.

Agra, Anderson, Tecnored Desenvolvimento Tecnológico S.A., Brazil

Co-Author: Guilherme Gonçalves, Tecnored Desenvolvimento Tecnológico S.A • Manoel Gonçalves, Tecnored Desenvolvimento Tecnológico S.A • Ismael Flores, Federal University of Rio de Janeiro • Alex Campos, Tecnored Desenvolvimento Tecnológico S.A • Bruno Flores, Federal University of Rio Grande do Sul • Ronald Lopes, Tecnored Desenvolvimento Tecnológico S.A • Stephen Potter, Tecnored Desenvolvimento Tecnológico S.A

Abstract: As an energy-intensive and waste-generating, the traditional iron and steelmaking industry is challenged to find pathways to meet climate change mitigation and sustainability demands from modern societies and governments. In this sense, the steel industry is trying to meet the challenge of a fully circular economy in a near future. The minimization of solid waste sent to landfill and the mitigation of CO2 emissions are seen as key points for the sector. Tecnored is a smelting reduction process for hot metal production based on self-reduction agglomerates (SR briquette), flexible to use iron-bearing and carbonaceous wastes from steel plants, such as sludges and dust in an efficient way. Due to the Tecnored compact design, the process can operate without coke, using a broad range of carbonaceous materials in agglomerated form (fuel briquette), allowing the technology to heavily rely on sustainable biomass-based fuels, promoting drastic CO2 reduction during hot metal production. The validation of the Tecnored process and its flexibility for raw materials has been done in the last 10 years through many campaigns in a 40 kta demonstration plant. Now the technology is being scaled up to the first commercial plant, which has its start-up schedule 2026 in Brazil. In this work, we present the basics of the technology when operating with residues, including the recycling performance during the last two campaigns in the demonstration plant. Also, an economic evaluation of crude steel production using Tecnored and a comparison with other potential routes for waste recycling. The objective of this publication is to highlight the role that Tecnored can play in the future to contribute to a sustainable low-carbon circular economy iron and steelmaking.

Agra, Anderson, Tecnored Desenvolvimento Tecnológico S.A., Brazil

Co-Author: Ismael Flores, Federal University of Rio de Janeiro • Manoel Gonçalves, Tecnored Desenvolvimento Tecnológico S.A • Bruno Flores, Federal University of Rio Grande do Sul • Alex Campos, Tecnored Desenvolvimento Tecnológico S.A • Ronald Lopes, Tecnored Desenvolvimento Tecnológico S.A • Guilherme Gonçalves, Tecnored Desenvolvimento Tecnológico S.A • Stephen Potter, Tecnored Desenvolvimento Tecnológico S.A

Abstract: The iron and steel production sector accounts for 7-9% of the total CO2 emitted worldwide, being one of the most energy-intensive and large-volume production industries. As a result, governments and companies are committed to mitigating its CO2 emissions, an important requisite for the future development of the steel industry. Most of the world's steel is obtained through the blast furnace-basic oxygen furnace (BF-BOF) route, with the blast furnace being responsible for roughly 90% of the total carbon emissions of the entire steelmaking route. However, reducing BF CO2 emissions is challenging due to the technology's high maturity and raw materials. Tecnored company has extensive experience developing cold agglomerated briquettes for its smelting reduction technology, which is 100% fed with self-reducing briquettes and fuel briquettes. With the increasing demands for CO2 reduction in the iron and steel sector and Tecnored background, two low-carbon briquetting solutions were developed for hot metal production (BF). The first one is a bio-briquette for cokemaking (BBC). The replacement of coking coals by biomass-based materials for coke production is challenging, usually limited to no more than 1-2% only. BBC has promising results indicating up to 10% replacement ratio while keeping high coke quality. The second low-carbon solution developed by Tecnored is the catalyzed briquette for blast furnace (CBB). CBB is a combination of carbonaceous sources (coking/non-coking coals, biocarbon, etc.), a catalyst (iron and calcium bearing materials) and binders, which is carbonized in mild conditions to produce a material with the ideal composition and strength for blast furnace application. The utilization of CBB associated with the sinter layers in BF has the potential to decrease reserve zone temperature hence coke consumption. In this study, the main characteristics and features of the briquetting solutions (BBC and CBB) were discussed regarding their potential for use, process impact and potential for CO2 mitigation.

Agraniotis, Michalis, Mitsubishi Heavy Industries EMEA Ltd., Germany

Co-Author: Takashi Kamijo, Mitsubishi Heavy Industries Engineering, Ltd.

Abstract: Decarbonization in Hard-to-abate industrial sector is considered as one of the key future challenges in Europe and worldwide towards reaching the targets of Paris Agreement. Electrification and use of hydrogen, are two emerging technologies which may become relevant for specific industrial applications. Nevertheless, carbon capture is already proven in the large industrial scale and is expected to play a key role in the decarbonization of these sectors through combination with permanent storage. MHI has more than 30 years’ experience in development and commercialization of its proprietary amine based carbon capture technology and has 14 industrial scale references, including the world’s largest post combustion CO2 capture project, Petra Nova. MHI has recently commercialized the “Advanced KM CDR ProcessTM”, which utilizes the new generation of its proprietary solvent KS-21TM. The new solvent has improved characteristics such as higher stability and lower volatility, and brings competitive advantages in terms of capex and opex for new carbon capture projects. In the present paper the experience from projects in Hard-to-abate sector like steel industry, is assessed. For the development of new large scale projects Feasibility and Pre-FEED study type of activities are combined together with specific test campaigns in dedicated mobile test units. In this way the impact of specific flue gas composition on the performance of the process and quality of captured CO2 from steel industry can be analyzed, so that the outcome can directly facilitate the design of the large scale project.

Ahmed, Mo, Schneider Electric USA, United States

Co-Author: Ling Dou, Schneider Electric • Rajesh Sharma, Schneider Electric

Abstract: The steel industry has embarked on a decarbonization journey to address significant carbon footprint, with hydrogen a key abatement lever for decarbonization, steelmakers are facing challenges to scale hydrogen production at attractive cost, including sourcing of sufficient renewable energy. Scaling green hydrogen production to giga-watt scale requires intense efforts in terms of analysis around electrical designs, electrolyser selection and optimization across the complete value chain. Technologies like digital twins which help in analysis of hybrid electrical networks and the process needs are helping engineering companies to design the green hydrogen production facilities which are fit for purpose and scalable. Similarly, automation with integrated architecture helps in managing the complete production cycle from choosing the cheapest energy source to management of intermittency of power generation and associated downstream continuous process. Digital twins developed during design phase support efficiency improvement during operate and maintain phase supporting energy optimization and reduced unscheduled downtime. We will discuss how during different phases of the project, such digital solutions help de-risk the projects, improve performance and reduce overall cost.

Ahsan, Amit, SECOPTA analytics gmbh, Germany

Co-Author: Christian Bohling, SECOPTA analytics GmbH

Abstract: Due to modern days automation processes inside rolling mills, the risk of material mix-ups is pretty low. However, given the rising demand for smaller production lots and the constantly growing number of steel grades, reliable material identification along the entire process chain is still one of the highest concerns. The current state-of-the technologies (e.g., spark, magnetic induction testing) fall short to guarantee a 100% reliable check at the end of the rolling process (e.g., before shipment). On the other hand, at the beginning of the rolling process, manual activities such as picking input or semi-finished material from the storage to charge into reheating furnace often leads to material mix-ups as well. Particularly, when safety-critical components are concerned, a mix-up can have catastrophic consequences (e.g. shipment cancellation, penalty charges, loss in reputation). With fully integrated precleaning (e.g. scale, decarbonization layers), SECOPTA developed LIBS (laser-induced breakdown spectroscopy) based sensor can analyze every moving bar (bright or black) more precisely (with respect to heat/ melt shop value) at the speed of 2 m/sec. Additionally, it can check each billet or ingot before the charging of reheating furnace assuring maximum safety without any human interference. Depending on the risk of mix-up, fiberLIBS can be integrated into the existing process (e.g., finishing line, NDT line, before reheating furnace) and fully compatible with Manufacturing Execution System Systems (MES), ensuring industry 4.0, 100% mix-up testing with significantly low maintenance and operating costs. Since 2019, SECOPTA has carried out multiple successful installations in highly reputable special steel manufacturer facilities and years of 24/7 process operation have proven that fiberLIBS can detect out-of-spec material with more than 99,9 percent reliability. The paper followed by the Estad presentation will introduce this inline LIBS-based Positive Material Identification (PMI) technology and discuss its reliability with real-life process data.

Aigner, Michael, Eisenwerk Sulzau-Werfen, R. & E. Weinberger AG, Austria

Co-Author: Henk Bolt, Tata Steel Nederland Technology B.V • Danny Beentjes, Tata Steel Nederland Technology B.V • Thomas Trickl, Eisenwerk Sulzau-Werfen, R. & E. Weinberger AG • Leonel Elizondo, Eisenwerk Sulzau-Werfen, R. & E. Weinberger AG • Michael Brandner , Eisenwerk Sulzau-Werfen, R. & E. Weinberger AG • Armin Paar, Eisenwerk Sulzau-Werfen, R. & E. Weinberger AG • Maximilian Reiter, Eisenwerk Sulzau-Werfen, R. & E. Weinberger AG

Abstract: Graphitic HSS roll grades such as ESW’s brand VANIMO can be considered as the latest developments for the last finishing stands in hot strip mills. These roll grades are developed on the basis of the alloying concept of (Carbide Enhanced) Indefinite Chill work roll materials. During the development of VANIMO, the amounts and types of carbide-forming elements were increased and adjusted in the direction of cast HSS roll grades. The microstructure of graphitic HSS roll grades, therefore, consists of tempered martensite, cementite, and several different carbide types as well as a well-defined amount of free graphite. The main purpose of graphitic HSS roll grades is the combination of the high surface quality of Indefinite Chill alloys as well as the high wear resistance of HSS roll grades. The development and introduction of this very advanced roll grade at Tata Steel’s Direct Sheet Plant in The Netherlands were done in close cooperation between the customer and the roll supplier. Several systematic steps were taken to increase the wear performance from Carbide-Enhanced Indefinite Chill grades to the more advanced grades to reach the highest alloyed roll grade VANIMO. In every development step, the surface quality of the roll grades was carefully monitored. This paper describes the improvement of the wear performance for roll grades in the last finishing stands in the Direct sheet plant by introducing higher alloyed roll grades, up to VANIMO. Different appearances of the strip surfaces in relation to the work roll material are presented and the root causes for these phenomena are explained. Finally, some possible strategies to improve the surface quality of graphitic HSS roll grades are presented.

Al-Gahtani, Masoud, SABIC, Saudi Arabia

Co-Author: Faisal Al-Ghamdi, SABIC • Vinod Yadav, SABIC

Abstract: EFFICIENCY OF USING POLLARD-TYPE NITROGEN SHROUD FOR MEDIUM CARBON STEELS ON MINIMIZING RE-OXIDATION DURING CASTING. Masoud Al-Gahtani, Faisal Al-Ghamdi, Vinod Yadav This paper discussed the effect of using pollard-type nitrogen shroud during production of medium carbon steel in order to minimize re-oxidation of the liquid steel. Polar-type nitrogen shrouds protection were mounted to tundsih nozzles at the bottom of the tundish provided an effective protection. The shrouds were designed with flow rate and investigated during production of medium carbon steel billets drawn for low thickness wire rods. Plant trials were used to examine the protection efficiency polar-type nitrogen shroud, and the mechanism of nitrogen entrapment during the casting of medium carbon steel billets was analyzed.

Albers, Stefan, PSI Metals GmbH, Germany

Abstract: With increasing share of renewable energy, energy availability will become more volatile. To respect resulting energy consumption constraints from energy providers, to contribute to grid stability and reduce energy costs, we need to forecast energy consumption cross-line in the production planning and scheduling process. This requires product and process specific forecasting models for all operations. PSI Metals applies these models to forecast and optimize cross-line schedules respecting energy availability constraints. Using a KPI driven Qualicision solver, automated energy procurement buys and sells in day-ahead and intra-day trading. This enables easy adaptation to changes in consumption forecasting whenever production plans are altered due to actual situations. It further enables energy procurement to cash in on short-term energy prices. This paper outlines deriving the forecasting models from production and EMS data as well as the combination of detailed forecasting with KPI-driven automated energy trading systems.

Alghamdi, Faisal, SABIC, Saudi Arabia

Abstract: Medium carbon steels are mostly used for spring and nail manufacturing applications. In this paper, the drawability and cold headability performance of wire rods, AISI 1040 and AISI 1045, produced using pollard-type nitrogen shroud casting were investigated. The material has been characterized “as hot-rolled” using several analytical methods: Decarburized depth/Core segregation, optical microscopy, and Nonmetallic Inclusion rating analysis. Both grades of AISI 1040 and 1045 were then deep drawn to wire to size 2.87 and 1.3 mm, respectively. Produced medium carbon steel wire rod had high ductility and excellent drawability with limitation in cold headability.

Alharbi, Mansour, SABIC, Saudi Arabia

Co-Author: Brandao Jr. Renato, Retired • Neeraj Tewari, SABIC • Abdullah H. Kareem , SABIC

Abstract: The objective of this study was to simulate the fluid flow performance of billet caster tundish using a mathematical model in order to optimize the tundish furniture style and location for best steel quality and/or effective flow control. A six-strand billet caster tundish presents various challenges such as being able to maintain the same casting temperature, homogenous chemistry and similar steel cleanliness in every strand. These challenges make the fluid flow phenomenon in a six-strand tundish more complex. The fluid flow characteristics and tundish performance were derived by performing the Residence Time Distribution (RTD) analysis. The model was developed successfully to simulate the flow characteristic and pattern inside the tundish. The simulation results were validated against the literature. The RTD analysis drove the conclusion that removing the current used flow modifier impact piece would help to enhance the discharging rate and reduce the dead volume zone inside the tundish. This then would enhance maintaining the molten steel temperature homogeneity during casting process.

Alharbi, Mansour, SABIC, Saudi Arabia

Co-Author: Chermak Edrisse, SABIC • Ahmad Pasha Farhan, SABIC • Tarek J. Jamaleddine, SABIC • Turki Alrasi, SABIC • Neeraj Tewari, SABIC

Abstract: The electric arc furnace (EAF) based steelmaking process utilizes DRI and/or scrap as raw material and electricity as an energy source. Usually, the DRI /molten Iron has a high amount of carbon content, up to 4%. Therefore, carbon removal (decarburized) is one of the prime interests of the steel industry. In usual practice, an electric arc furnace uses an oxygen jet from the top, which performs decarburization and results in the formation of CO bubbles. Furnace bottom stirring is driving the bath homogeneity and maximizes the decarburization rate. The high-level quantum chemical energetics and chemical kinetics calculations confirm that, soft oxidant CO2 reacts with carbon presents in molten steel but at a slower speed than O2. Therefore, co-feeding CO2 in mixture with the Oxygen stream from the top side will not contribute to the objective of the process decarburization rate/efficiency enhancement due to reaction selectivity towards O2 rather than CO2. Nevertheless, introducing an optimal quantity of CO2 to substitute and/or replace bottom-stirring Argon/Nitrogen gas should enhance the process performance. Therefore, introducing CO2 gas from the bottom considering the absent of Oxygen at this zone as a replacement or partial replacement of N2/Ar would start decarburization at early stage when it is challenging to provide sufficient significant amount of oxygen from the top. Density functional theory (DFT) based thermodynamic and kinetic used to evaluate the potential advantage using CO2 in bath stirring and its impact on overall decarburization. The high-level Thermodynamics and Kinetics calculations have been performed manually using Quantum chemical calculations within the framework of DFT based the first principle formalism. The molecular level calculation was performed using molecular DFT however, for solid-state calculation; a plane wave DFT approach has been used. In the current setup of steel making process there are multiple competitive reactions occurs within the steel bath. The CO2 injection into steel bath will initiate several other reactions besides decarburization. In this study a comprehensive investigation of thermodynamics and kinetics profiles of all the possible reactions at the operating temperature of the furnace (~ 1600˚C) helps, understand the feasibility of CO2 injection into steel bath, Thermodynamic and kinetic profiling of all reactions using Gibbs free energy to understand the competitive feasibility of different reactions. Thus, based on comparison of energetics of the most significant reactions in the steel bath, introducing CO2 from the bottom in combination with stirring gas shall have positive impact on overall decarburization rate of molten steel bath.

Ali, Mohammed Liaket, German Aerospace Center, Germany

Co-Author: Uwe Riedel, German Aerospace Center • Quentin Fradet, German Aerospace Center

Abstract: Full-fledged computational modeling of Direct Reduction (DR) reactors encompasses single pellets models and the step-wise scaling-up to industrial-scale reactors. The specific focus lies here on scale-up from a single iron ore pellet to a fixed-bed reactor model. However, this process poses several challenges like, a) Synthetic packed-bed structures need to be generated instead of a realistic image-based method due to the high cost, b) Good quality mesh for multi-pellet fixed bed is difficult to generate and c) Scaling up to a CFD environment is cost-intensive. Furthermore, the correct modeling of transport and kinetics-related processes for a single pellet is a prerequisite for a meaningful scale-up. This has not yet been demonstrated. In this work, the chemistry and transport data for the reduction of single iron oxide pellets with H2 gas, obtained from a previously developed 1D solid porous model will be used. The purposes of this article are 1) Proposing a CFD model that reproduces single pellet reduction experiments with H2 gas for wide experimental conditions in a 3D-CFD environment. 2) Computationally generating a random packing of 212 industrial pellets (0.5 kg) by applying the discrete element method (DEM) to simulate a lab-scale fixed-bed reactor. 3) Creating a 3D domain, based on the particle position data from the previous step and meshing the pellets and the voids among them in different refinements. 4) Reproducing a multi-pellet fixed-bed experiment with pure H2 from literature. 5) Investigating the effects of temperature variations in the bed. In this way, the concept of scaling up to multi-pellet fixed bed model simulation with H2 will be demonstrated successfully.

Almquist, Eric, Chicago Heights Star Tool & Die Works, Inc., United States

Abstract: Reliable, continuous, non-contact, online monitoring of metal’s surface cleanliness is a reality after years of challenges with laser reliability within finishing lines. Premium sheet finishing lines (e.g., CGL, CAL/CAPL, tinning) typically utilize cleaning sections to remove surface contamination early in their process to optimize finished product quality and operational reliability. Until today there hasn't been a practical method to continuously monitor surface contamination. Oftentimes, cleaning sections are complex, multi-stage systems with significant operating costs with little, to no, ability to verify results until a problem appears because of insufficient cleaning. This leads to operation mentalities of wastefully operating all cleaning systems ‘flat-out’ no matter the cost or because of some other ‘process control plan’ based of legacy experience, intuition from archaic wipe tests, arbitrary hunches, or even running a ‘trouble-shooting’ scheme of ‘changing-this and adjusting-that’ until some level of satisfactory outcome is attained after generating tons of scrap. The TST.1 systems utilize the elegantly simple technique of laser ablation (LA) to provide real-time evaluation of surface contamination levels along the entire length of the coil, generating high-resolution data as frequent as 10 Hz. Operators can visualize cleanliness trends before they become a problem and even ‘throttle’ the cleaning section to clean the surface ‘sufficiently’ versus running flat-out. The system has ability to display fine changes: differences in electrolytic cleaner phase, individual brush performance, changes in spray sections, etc. Realtime cleaning section optimization is now possible. This practical presentation will provide details of the TST.1 systems being used within customers’ operations including actual results from interesting cases. Other details: fundamentals of why cleanliness is important; various cleanliness tests used over the decades; the difficult path of getting lasers to survive in process lines; along with other technical details of the system.

Altay, Mert, Erdemir, Turkey

Co-Author: Erdal Ünal, Erdemir • Selda Daldal, Erdemir • Kağan Keler, Erdemir

Abstract: Iron ore sintering raw blends include various materials such as iron ore, coke, limestone, and recyclable ironmaking and steelmaking byproducts such as return sinter, slags, and sludges. One of these byproducts is basic oxygen furnace (BOF) slag which due to its high calcium and iron content regularly used in sintering by industry. As a recyclable material, it could partially substitute raw materials that include calcium and iron thus could provide sustainability and cost advantages to integrated steel plants. However, due to its impurity content, and physical and phase structure it could also deteriorate process efficiency or product properties. Thus, it is highly beneficial to define the effects of the BOF slag ratio in the raw blend on sintering parameters and sinter product. In this study, pilot scale sintering experiments were conducted with different BOF slag rates in raw blend changing from %0 to %9.25 and changes at the process parameters such as flame front speed, productivity and yield, and product properties such as tumbler index, shatter index and reduction disintegration index are investigated. The result showed that BOF slag usage could increase yield due to its lower loss on ignition compared to limestone however sintering time, productivity, and RDI could worsen with an increase in BOF slag usage rate.

Alter, Michael, ALTER Blast Furnace Consulting, United States

Co-Author: Andrii Moskalyna, ISI NASU • Bohdan Kornilov, ISI NASU • Oleksii Chaika, ISI NASU

Abstract: For the last 100 years, trends and classification of blast furnaces blow-in have been discussed. Development of blow-in subdivided into 3 periods: 1st - continued until end of 30s of XX century, characterized by lack of scientific knowledge, mysticism and based on previous experiences; 2nd - until the beginning of 70s, when "traditional" blow-in technology was mastered with one problem - difficulties with opening first casts and simultaneously overheating top; 3rd period is in progress nowadays, it includes developments of new methods for intensifying heat transfer during blow-in and scientifically generalize blow-in techniques. Major objectives of blow-in are to bring the blast furnace to normal operation, observing safety rules, in a short time, without significant costs, and to protect blast furnace and auxiliary equipment for long-term productive operation. These objectives are closely related to design features of blast furnaces, including the cooling system, type of lining, and furnace sizes, which have steadily increased from less than 500m3 to 5600m3. Complexity of understanding the processes of burden column heating during blow-in period that forms a gas flow and cohesive zone in it is the reason for numerous discussions about rational blow-in techniques: methods for calculating and placing burden layers in a blast furnace, usage of various additives to hot blast (nitrogen, natural gas, blast furnace or coke oven gases, oxygen, steam, etc.), the rate of hot blast volume increasing, its temperature ramp up and pressure drops trend along the burden column. In addition, a potential usage of wood in the blow-in burden, installation of narrowing rings into tuyeres or plug part of tuyere for blow-in are discussed. Recommendations for blast furnaces blow-ins and comparison of "Traditional" blow-in vs. "Progressive" and blow-in with nitrogen, developed by ISI NASU, is presented.

Alter, Michael, ALTER Blast Furnace Consulting, United States

Co-Author: Andrii Moskalyna, ISI NASU • Mykola Izumskyi, ISI NASU • Vitaliy Lebed, ISI NASU • Bogdan Kornilov, ISI NASU • Oleksii Chaika, ISI NASU • Volodymyr Naboka, PJSC Zaporizhstal

Abstract: The article discusses results of calculations of energy and exergy balances in blast furnaces with possibilities of new and existing technologies for reducing carbon dioxide emissions and reducing coke consumption, increasing production of pig iron by injection into the hearth hydrogen and hydrogen containing fuel additives (coke oven, BOF, or natural gases), use of scrap, enriched top gas, increasing blast temperature, reducing heat loss and improving gas utilization. Calculations were carried out using original mathematical model developed in the ISI NASU for blast furnace total energy balance. There were assessed impacts of different technologies on reducing CO2 emissions and technical and economic blast furnace operating indexes in depending on changes in pulverized coal consumption, hydrogen and hydrogen-containing fuel additives rate and their combinations in a wide range. Have been determined limits of hydrogen and hydrogen-containing fuel additives for injection into the hearth of blast furnace, by the following factors: degree of direct reduction of iron, RAFT range, the availability of oxygen for blast enrichment and top gas temperature. Outcomes of study disclosed that CO2 emissions of blast furnace ironmaking can be reduced up to 25-30% by evolution of blast furnace operations which depends on investments, quality of raw materials, available energy, level of existing blast furnace operations technology. The effects of injection of preheated enriched top gas, clean scrap additives use, heat losses drop, actions to increase hot blast temperature, and optimization of gas distribution in the blast furnace on carbon dioxide emissions decreasing and technical and economic indicators of blast furnace operation were investigated. The results can be useful for determining the economic feasibility of different technological actions to reduce CO2 emissions in blast furnace ironmaking.

Alzayer, Mohammed, SABIC, Saudi Arabia

Co-Author: Mohamed Bahgat Saddik, SABIC

Abstract: As indicated by the principles of green chemistry, synthesis of materials must be done in a way that avoids hazards. One of the challenges in producing DRI (direct reduced iron) in shaft furnace reactors is ignition of the DRI pellets after discharge. In this study, the oxidation behavior of DRI pellets was examined using different sources of raw iron ore. Each type was reduced in lab using different conditions of reduction temperatures, reducing gas compositions, and pellets’ sizes. After generating reduction curves and comparing the reduction behavior of these pellets, they were exposed to severe oxidizing environment in order to compare how each condition responds to oxidation.

Anderson, Matt, Primetals Technologies US, United States

Co-Author: Paras Patel, Primetals Technologies US • Ruth Kirkwood-Azmat, Primetals Technologies US

Abstract: "Primetals Technologies Long Rolling is at the forefront of applying the latest smart digital solutions in the industry. Their vision systems, developed over several years, provide an extremely strong, smart digital portfolio with a focus on improving safety, reliability and maintenance, while increasing production, yield and quality. In addition, these systems provide previously unattainable insights into the rolling process. Prevention is far more economical than problem fixing. Primetals Technologies promotes a proactive, predictive, and preventive maintenance approach for all our customers. Vibration analysis allows accurate prediction for mill maintenance; enabling improved downtime scheduling. Data is collected both periodically and continuously by our proprietary condition monitoring and analysis systems. Long-term partnerships have been developed with our customers, using our vast predictive service knowledge and over a century of long-rolling experience. Sub-optimal roll cooling can lead to premature roll wear, reduced yield, and catastrophic failure. Primetals Technologies has developed a new roll cooling system with a quick-change, additive manufactured cartridge, which along with sensors, helps to ensure rolls are receiving consistent, optimized cooling. With increasing focus on safety, operators are restricted from approaching the mill to perform manual checks on section size, equipment status or adjust settings. A new guide series provides continuous feedback on section size, equipment condition and allows remote adjustments. In addition, an alternative section measurement system has recently been brought to market. The main focus of this portable device is again to keep operators away from the mill during production, while providing accurate, objective measurements. Other recent developments include crop length optimization, Laying Head/Stelmor vision control system, and a roll-change robot. The paper gives practical examples how the implementation of smart digital solutions in long rolling leads to an improved plant performance, optimized maintenance strategy and safer operation."

Anderson, Matt, Primetals Technologies US, United States

Co-Author: Thomas Wojtkowski, Primetals Technologies US • Martin Thiemar, Primetals Technologies US • Peter Osgood, Primetals Technologies US

Abstract: Optimizing the efficiency and availability of MORGOIL® bearings directly impacts rolling mill productivity and quality. Management is aware of the significant benefits associated with a well-run bearing monitoring program, however few companies have the resources or expertise to implement “predictive technologies” on their own. These systems are the basis for preventing problems and properly planning maintenance, thus achieving long-term mill success. Using condition monitoring technologies, Primetals Technologies has developed a suite of Predictive Maintenance and Monitoring strategies to monitor and assess MORGOIL® backup bearing operations to reduce unscheduled down time and to increase productivity. These techniques utilize a full complement of sensor technologies connected to a Human Machine Interface (HMI) to capture and interpret vital information from operating MORGOIL® bearings. The computer interface provides mill operators a ‘real time’ warning if bearing operating parameters exceed safe limits. Additionally, the system ensures that there is adequate oil flow to the bearings before rolling is started. These systems typically also fully monitor the lubrication system. Examples of existing systems built into new Primetals Technologies hot mills will be shown. Similar systems can be custom implemented in existing mills on an incremental basis depending on existing mill systems. A well implemented and managed MORGOIL® Predictive & Monitoring System, is the most effective method of managing risk, increasing reliability, and ensuring the best possible return on mill operation.

Argenta, Paolo, Executive Vice President, Upstream Business Unit, Tenova S.p.A., Italy

Abstract: Tenova’s innovative technologies can directly reduce environmental impact, enhance circularity through recycling and reusing waste, and be used to produce metals crucial to the energy transition. There are multiple approaches to sustainable development - Tenova partners with companies to develop customized solutions designed to reflect local conditions and sustainability regulations.

Ashburn, Ronald E. , Executive Director, Association for Iron & Steel Technology (AIST), United States

Co-Author: Brian J. Bliss, General Manger Programs and Publications, Association for Iron & Steel Technology • Samuel J. Kusic, Jr, News Editor, Association for Iron & Steel Technology

Abstract: Never in the last half century has the global steel industry faced as many challenges at once: overcapacity, supply chain insecurity, energy shortages, unfair competition and climate change. The problems are immense and have catalyzed the imperative for global steel decarbonization. North American steel producers are actively engaged in technology evolution to innovate process and product, and have invested in an advanced fleet of production assets that are highly automated, efficient, and above all, clean. This presentation will provide an overview of decarbonization strategies for North American steel producers and related efforts to rise above the current challenges.

Aslan, Özgür, Erdemir Oyak Mining Metalluryg Turkey, Turkey

Co-Author: Aytaç Altan, Zonguldak Bulent Ecevit University • Rıfat Hacıoğlu, Zonguldak Bulent Ecevit University

Abstract: Pulverized coal injection (PCI) plants play significant role in reducing the blast furnace total energy consumption. Injecting desired amount of pulverized coal to a blast furnace is important not only for energy saving but also for process health. Pulverized coal injection rates from a PCI plant to a blast furnace is automatically controlled by logical algorithms and PID controllers of the automation system libraries. Since industrial plants do not have exact mathematical model, parameters of PID controller are determined according to the system dynamic response observed as a result of the experimental tests. Due to the system dynamics changes by time, the controller can not provide desired proves variable and parameters of PID controller need to be re-configured. Model reference adaptive controllers (MRAC) are used in many industrial applications in which the mathematical model of the system is unknown and the dynamic response of the system is changing over time. In this study, MIT and Lyapunov based model reference adaptive controller is applied in a pulverized coal injection tank pressure control system of a PCI facility, which is the critical process ironmaking energy consumption. In addition, fuzzy based adaptation gain regulation is proposed to improve MRAC performance. Adaptation speed and performance of MRAC is analyzed under disturbance effect. Control performance results of fuzzy based gain regulation MRAC is compared with PID controller and It is observed that MRAC shows better performance.

Astoria, Todd, Midrex Technologies, Inc., United States

Co-Author: Matt Hargreaves, TUTCO SureHeat

Abstract: The iron and steelmaking industry is experiencing rapid market change and technology developments. One of the key drivers for the market change is the need to improve the environmental impact of the processing routes. The reduction of CO2 emissions is one of the most important environmental goals facing the industry. The Direct Reduction (DR) – Electric Arc Furnace (EAF) is one of the most promising technologies to achieve CO2 reductions. In order to achieve the reduction, the DR plants are extending their fuel options to include green hydrogen. Hydrogen has great promise for the direct avoidance of CO2 from the DR route when used as the process fuel; however, hydrogen has drawbacks when applied as a fuel for heating the Process Gas in the conventional combustion-based heating unit operation. Generally, green hydrogen is produced from electrolysis. If hydrogen is used as a fuel in a combustion system, then it can reduce the CO2 emission compared to a typical fossil-based fuel. However, inefficiencies are introduced when electricity is used to produce hydrogen, which must then be transported to the facility. In order to overcome the inefficiencies then it is advantageous to use electricity to directly heat the Process Gas. This paper focuses on the advancements that are being made in the field of electrical heating of process gases in the Direct Reduction facility.

Atan, Mehmet Burak, İskenderun Iron and Steel Co., Turkey

Co-Author: Gökhan Güngör, İskenderun Iron and Steel Co. • Arif Aksoy, İskenderun Iron and Steel Co. • Koray Aray, İskenderun Iron and Steel Co. • Onur Marti, İskenderun Iron and Steel Co. • Serdar Günbay, İskenderun Iron and Steel Co. • Erkin Yekda Gedik, İskenderun Iron and Steel Co.

Abstract: In the iron and steel industry, water is one of the most significant inputs for production. The most common uses of water in the iron and steel industry are product surface cleaning, cooling, protecting equipment and improving working conditions for employees. The water which uses for surface cleaning contacts with the final products. Therefore, water quality has tremendous importance at this point. The quality of the water that comes into contact with the product can cause undesirable impacts in the quality of the material from time to time. Variables such as the chemical structure of the water, the residence time on the material, and the chemical type used in the treatment of the water affect the product quality. During the coil production in the hot rolling mill, it was determined that white spots on the coil and in detail examination, the element S broke the layer in the scale and and a white spot formation was detected with Cl reacted with AgNO3. After the occurrence of this situation, the limit values of the circulation water in contact with the product, the water source to be used and the chemical treatment of the circulation water were overhauled, and the problem’s repetition was prevented. Key Words: Water Quality, Coil Production

Athayde, Maycon, Minerai de fer Quebec, Canada

Co-Author: François Lavoie, Champion Iron • Josiane Caron, Quebec Iron Ore

Abstract: Cold bonding pellet can turn into and important process in the ironmaking industry, eliminating carbon intensive process. However, this route presents high-temperature metallurgical challenges due the behavior in the blast furnace process. The ability of the material to maintain its strength and structure and resist degradation is crucial for producing high-quality h-CBP. In the last years, Champion Iron, a high-grade iron ore concentrate producer in Quebec, Canada have been developing a solution to supply to the ironmaking industry. Previous technologies focused on either organic or inorganic binder systems. A hybrid inorganic-organic binder was formulated, to overcome the weaknesses of the other. Unlike cementitious binders, no thermal conversion is occurring around 750°C, leaving much more leeway to maintain cohesion up to the cohesive zone. Organic portion of the binder provides bonding with both the iron oxides and the inorganic binder, to give the required physical properties. Additionally, the organic content aids the manufacturing process and aids stability, when in the unhardened phase. The 10 m drop test results of 86.9% -6.3 mm and 2.0 % -0.5 mm are slightly below the range of seaborne trade pellets values of 92.4 %-6.3mm and 1.5 %-0.5mm. The reducibility of 0.67 %O2/min is higher traded acid pellets value for BF (0.4-0.6 %O2/min). In this work a modified BRASS test is presented to better characterise the behavior of the h-CBP’s in the non-isothermal blast furnaces. Also, the test was interrupted in different zone to evaluate the progression of the reaction. The results presented also satisfactory reduction rate at the end of thermal reserve zone, and lower fine generation as compared with traded pellet. Champion Iron has been successfully designing a new concept that supports decarbonized hot metal production from a blast furnace with a stable contribution to the ferrous burden, like a traditional product.

Aula, Matti, Outokumpu Stainless, Finland

Abstract: High amount of refractory materials are consumed in steelmaking due to high processing temperatures. Refractory materials typically contain MgO, which is also an important slag former in electric arc furnace (EAF). A normal EAF practice is to operate with slag composition close to MgO saturation limit to decrease the potential of the slag to dissolve MgO-containing refractories. One method to provide MgO to the slag is to charge crushed spent refractory bricks to EAF. The most important parameter in utilization of bricks is the dissolution speed of the crushed bricks. If the recycled bricks do not dissolve fast enough to slag, the liquid part of the slag is not saturated with MgO and the refractory wear is increased. In this work the dissolution of three spent refractories of different grain sizes are tested in chamber furnace containing a magnesia brick as a crucible. The starting slag is synthetic slag similar in composition to EAF slag obtained in stainless steel production prior the MgO dissolution. In the trials different spent refractories are added to the synthetic slag mix to provide MgO. The holding time and temperature is set to obtain MgO saturation of slag when no sources of MgO are used in the original mix. The slag samples obtained from the chamber furnace are analyzed with x-ray fluorescence spectrometry (XRF) to obtain the overall composition and with scanning electron microscope (SEM) to acquire qualitative estimate of the presence of undissolved refractories in the slag. The change of total MgO content of the slag with different MgO sources is evaluated to obtain the estimate of the amount of undissolved spent refractory.

Auzmendi, Itsaso, Sarralle, Spain

Abstract: Success stories towards CO2 neutral steelmaking via hydrogen-based technologies Sarralle has decades of experience on helping steelmaking companies in the challenge of decarbonization and sustainability. Moreover, through their division Environment & Energy, we can offer technological solutions for industrial sectors related to the Circular Economy and Energy, including the integration of green hydrogen technologies in the industry. Sarralle offers oxy-combustion and hydrogen technology applicable to EAFs, Ladle and Tundish Preheaters, Reheating Furnaces and Oxyfuel-Cutting, thus enabling savings in natural gas consumption and the total decarbonization of these equipment. Sarralle, together with one of its European customers, has implemented their oxy-combustion and hydrogen technology in a ladle pre-heater, using 100% hydrogen. The Spanish company owns also a prototype of a reheating furnace at scale, designed to operate with 100% hydrogen, both with air and oxy-combustion burners, and they are currently working on the conversion of an industrial reheating furnace in a European steelmaking plant, for the installation of their oxy-combustion and hydrogen technology in one furnace zone. The goal of this cutting-edge technology offered by Sarralle is to optimize the process efficiency as well as to reduce the emissions generated in existing installations, replacing the air used as an oxidizer with oxygen, being able to keep natural gas as a fuel, or taking a step further by using 100% green hydrogen. By using green hydrogen, all CO2 emissions are eliminated as only water vapor is generated in its combustion.

Avsar, Ahmet Mithat, İsdemir, Turkey

Abstract: The innovative technology and sophisticated control systems for hot rolling mills has opened up new possibilities for designing and engineering of efficient systems and overcome common problems specific to processes. Performance of rolling mills and subsequent processes such as coil box equipment are key to successful production in today’s World of steel manufacturing. In the Coilbox, the transfer bar which is coming out of the roughing mill is coiled. Unwinding is effected in the reverse direction. The tail end of the bar runs first into the finishing mill. The Coil Box Stabilizer 1 is installed on the Cradle Roll 1A/1B that guide the transfer bar into the Coil Box. Stabilizers consist of stabilizer plate and guide rods, and are used for centering the coil position. The stabilizers are operated by means of hydraulic cylinders with position transducer to ensure the stability of a coil during coiling and uncoiling operation. In this paper, When the transfer bar starts coiling to the defined diameter, the stabilizer moves to short stroke position – set point is function of slab width, offset and short stroke value with position control. The control mode is switched to force control when the guide plate comes into contact with the transfer bar. But this process can lead to cobble situation especially tail end starts to open… This paper introduces In this paper …tail ..problem is examined Succesfully applied solution is presented… by improving working principle of stabilizers… intelligent mechanism is adapted o existing working modes… intelligent force control first by sensing if … occurs then prevenitive measure is taken by switching the mode from position control to force control if force level exceeds certain limit .. and then.. stability of tail of transfer bar mqaintained… thus preventing transfer bar to stuck in down stream equipments such as stabilizer 2, FM Stands

Baco, Ondrej, Thermo Fisher Scientific Inc., Czech Republic

Co-Author: Roger Maddalena, Thermo Fisher Scientific Inc.

Abstract: At the end of the hot rolling process, microalloyed steel will form nanoscale precipitates of compounds such as NbC and TiN. These precipitates have the potential to improve properties by grain refinement and precipitation hardening. Precipitates with smaller size and higher number density typically yield higher strength. The rate of cooling after hot rolling will control the precipitation and coarsening of these particles. One of the challenges is to obtain a statistically meaningful distribution of their size, shape and composition as up to now this has only been possible with tedious, manual analysis. In this study an electron microscopy workflow is presented where the acquisition of images and chemical information is fully automated, even for overnight analysis on large area samples. The automated TEM allowed processing and comparing a statistically relevant number of particles (thousands) of steel lamellae samples from the coil head and coil middle. With these workflows, the time to improve processes and to develop a new steel product can be reduced and R&D manpower can be freed up for new responsibilities.

Baek, Min-Seok, Hyundai Steel Co. , Korea, Republic of

Co-Author: Yong Soo Jeong, Hyundai Steel Co. • Seung Min Hur, Hyundai Steel Co. • Daeho Yun, Hyundai Steel Co. • Kwan Wook Kim, Hyundai Steel Co.

Abstract: Recently, the steel applied to car bodies continuously requires high- and ultra-high strength steels. Accordingly, many researchers have conducted research on the development and strength improvement of dual & complex phase steel. As various studies progressed, the strength of steels increased, but a serious problem of edge cracks was formed, and many researchers made efforts to solve the problem. In the past, the cooling temperature was improved during the hot rolling process to reduce the martensite fraction, which directly affects edge crack formation. In addition, our company has conducted tests on various cooling temperatures and pattern changes to effectively roll steel plates. However, a unique phenomenon was observed in which edge cracking occurred at higher cooling temperatures. Therefore, in this study, the effect of ROT condition on edge crack formation was investigated, and the edge crack formation mechanism was discussed in connection with the microstructure analysis.

Baniasadi, Mehdi, Paul Wurth S.A., Luxembourg

Co-Author: Florent Mauret, Paul Wurth S.A. • Peter Kinzel, Paul Wurth S.A. • Fernand Didelon, Paul Wurth S.A.

Abstract: The steel industry, especially traditional ironmaking is among the largest contributors of greenhouse gas emissions, attributable to approximately 7% of total emissions, because the Blast Furnace (BF) process was initially designed for the utilization of carbon-containing fossil fuels. Considering economic reality and CO2 emission targets, Paul Wurth has reassessed the blast furnace route and ended up with a solution named EASyMelt™, Electrically Assisted Syngas sMelter. In this contribution, an in-house numerical model (BFinner model) is utilized to investigate the EASyMelt™ concept for a blast furnace. First, the validation of the BFinner model with operation data of processes with medium to high levels of H2 load will be deliberated. Then, the model gives an insight into the feasibility of the EASyMelt™ with high H2 load and a minimum possible coke rate resulting in a significant coke saving.

Bansal, Akshay, ArcelorMittal, France

Co-Author: Gérard Griffay, ArcelorMittal Global R&D • Dominique Sert, ArcelorMittal Global R&D • Antoine Moussalem, ArcelorMittal Global R&D • Elise Vouriot, ArcelorMittal Global R&D

Abstract: Regenerative thermal exchangers are thermal devices capable of capturing & storing heat from a hot source and releasing the stored heat to a cold sink intermittently, repeating the cycles and therefore regenerating. In iron & steel industry, these exchangers are present in the form of hot blast stoves (hot air injected in blast-furnaces tuyeres) where the hot source is industrial gas combustion fumes, the cold blast constitutes the cold source and intermediate regenerator may typically be a checkerwork of refractory bricks or more recently a packed bed of refractory balls or pebbles. To support design and higher performance of pebble type regenerators, a numerical model of simplified combustion combined with heat transfer in a packed bed of pebbles is presented. Model results show a good order of magnitude of the bed temperature and its spatio-temporal gradient during both on-gas and on-blast cycles, in turn found to be aligned with experimental results in a laboratory scale pebble bed. The impact of the average pebble size on the heat transfer and therefore the global sizing of the regenerator is also discussed.

Bär, Kai K. O., adphos Innovative Technologies GmbH, Germany

Abstract: Today mostly thermal metal and especially most surface processes are based on fossil heating systems, whether oil or gas fired. These convection heat transfer driven ovens and driers, build very large, provide limited energy efficiency, little size/width power adjustment and show low dynamic power control characteristics. In addition, a systems inherent CO2-emission footprint of 200 – 300 g per thermal kWh heating energy is generated. The proprietary fully electro-thermal aLITE – (advanced Light Initiated Thermal Emission) Technology, a proprietary high power photonic heating and drying system enables now alternative solutions for a wide range of heating processes (e.g. defined heating, even locally focused up to 1,500 °C, air, special atmosphere, vacuum) and various drying and curing applications (e.g. rinse water, water-based coatings, water/solvent even powder based paints and coatings). The aLITE-processing allows instantaneous on/off and fully defined processes. Dynamic adjustable to mass, size and geometry changes. No need for pre-heating or standby operation. The extreme compact and energy efficient systems operation justifies attractive upgrade/replacement projects. Based on an introduction of the work principle of the aLITE-technology, already realized examples in commercial metal processing lines (e.g. pickling, hot roll, annealing, coil coating) are shown and competitive evaluated with traditional solutions.

Baron, Robert, Director Corporate Strategy , Swiss Steel Group, Germany

Abstract: Swiss Steel Group (SSG) is Europe’s largest electrical steel producer and the leading producer of specialty steel long products worldwide. Thanks to scrap-based steel production, SSG is also one of Europe’s largest recyclers and a leading provider of Green Steel solutions with a re-utilization rate of up to 100%. By closing the recoverable material cycle and the intelligent use of scrap, SSG and their products can considerably reduce the emissions of all supply chains at the starting point – compared to the blast furnace production route, e.g., for CO2, by more than 80%. Scope 3.1 emissions from purchased materials represent by far the largest share of the carbon footprint of SSG products. To further reduce it, SSG is extending its recycling expertise to include additional secondary raw materials and is increasingly working with its suppliers. The ongoing project to reclaim alloying elements from industrial waste is the only one of its kind world-wide! It provides a way to continue to reduce the use of primary ore-containing alloys in future and thus dramatically improve the footprint of stainless steels. Another crucial element is the close cooperation with suppliers and the collection of primary emission data. SSG is leading the way and is the first European steel manufacturer to contact its suppliers in a structured manner to be able to specifically measure and control the footprint of its own purchased raw materials.

Bartusch, Hauke, VDEh-Betriebsforschungsinstitut GmbH, Germany

Co-Author: Andreas Feiterna, AG der Dillinger Hüttenwerke • Dan Iulian Durneata, AG der Dillinger Hüttenwerke • Thorsten Hauck, VDEh-Betriebsforschungsinstitut GmbH • Yalcin Kaymak, VDEh-Betriebsforschungsinstitut GmbH

Abstract: The wear of the blast furnace hearth lining defines its campaign life. Due to the excessive costs of the relining, this is one of the most important economic factors of blast furnace ironmaking. As current state of art, hearth wear cannot reliably be measured directly. It is deduced from the temperature measurements in the refractory wall. Increases in the maximum observed temperatures are interpreted as additional wear. Nevertheless, the analysis of hearth wall temperatures suggests that other operational factors such as thermal hearth state and liquid flow also affect those temperature readings. Due to the harsh environment inside the hearth, it is impossible to directly measure factors describing such hearth processes. Dillinger BF5 is equipped with deep thermocouples reaching more than 1.6m inside the refractory. Dillinger and BFI have developed data streaming techniques enabling analysis of data from such thermocouples with comparable high time resolution of a few seconds. In parallel, Dillinger has performed continuous temperature measurements of the tapped hot metal. Applying methods from data science like analysis of data clusters and search for correlations, repeating temperature fluctuation patterns have been found. These patterns were related to either the tapping regime or to hot blast stove changes. The comparison of the process data distributions with and without such patterns provided valuable information on the inner hearth processes and the health of the hearth lining. This enables better and more reliable monitoring of the blast furnace hearth state.

Bartusch, Hauke, VDEh-Betriebsforschungsinstitut GmbH, Germany

Co-Author: Andreas Janz, Hüttenwerke Krupp Mannesmann GmbH • Fatima Demirci, Hüttenwerke Krupp Mannesmann GmbH • Thorsten Hauck, VDEh-Betriebsforschungsinstitut GmbH

Abstract: Until 2030 the EU has the objective to decrease CO2 emissions by 55%. The steel industry plans to reach substantial emission reductions by shifting to new steel production process routes like direct reduction combined with electric melting – but those process routes require availability of hydrogen, or in the first step natural gas in huge amounts and at competitive prices. However, currently the energy crisis decreases the economic feasibility of those new process routes. Consequently, it is reasonable to think about fast feasible bridge technologies to enable maximum CO2 mitigation in current blast furnace based process routes. One such bridge technology, already followed by multiple steel producers, is increasing the ore reduction share by hydrogen in the blast furnace. Higher hydrogen concentrations in the reducing gas lead to a shift between direct and indirect reduction, but also influence the process gas density and viscosity. Especially in Europe there is only little experience on blast furnace operations points with such higher hydrogen loads. HKM already announced to increase the hydrogen content in their blast furnaces by injection of coke oven gas. To prepare this operation, a study was executed comparing several historical operation periods at HKM with mixed natural gas and coal injection to similar periods with coal only operation. This study comprises analysis of differences in data distributions for nearly all data series from a blast furnace often used to rate the furnace working state. This article presents the differences found e.g. for the top gas properties, stack wall pressure and temperature measurements as well as other operational parameters to work out the changes in blast furnace working states with a higher hydrogen reduction share.

Barustan, Muhammad Irfan Ahadian, University of Newcastle, Australia

Co-Author: Thi Bang Tuyen Nguyen, The University of Newcastle • Evan Copland, The University of Newcastle • Damien O'Dea, BHP Group • Tom Honeyands , The University of Newcastle

Abstract: The utilization of hydrogen (H2) in blast furnaces is one of the alternatives to reduce greenhouse gas emissions. It was widely known that the addition of H2 can increase the reduction of ferrous burden materials and improve the permeability inside the blast furnace. However, the addition of H2 in a conventional blast furnace, with carbon monoxide (CO) as major reducing gas, might change the reduction degradation behaviour and affect the permeability in the upper part of blast furnace. Previous studies on reduction degradation show that there is still disagreement about the effect of H2 on degradation, especially when the H2 has partially replaced the portion of CO in the reducing gas. Moreover, the extent of degradation also seems to be dependent on H2 content and type of iron ore. Therefore, a study for reduction degradation for a different type of iron ore at different CO and H2 gas mixtures is still required. This study compares the reduction degradation of sinter and lump using a modified reduction degradation test. Various gas mixtures containing CO and H2 are used for the reduction test, including the simulated gas composition for blast furnace with maximum H2 injection. The extent of degradation is compared by the reduction degradation index (RDI) value and microstructure analysis are applied to observe the degradation mechanism.

Baumgartner, Kerstin, Primetals Technologies Austria, Austria

Co-Author: Simon Grosseiber, Primetals Technologies Austria • Andreas Jungbauer, Primetals Technologies Austria • Jürgen Scholler, Primetals Technologies Austria

Abstract: "The newest member of the Arvedi ESP family closes the gap between ultra-thin and thick gauges in endless production, being designed for 0.8 mm up to 25.4 mm with a yearly capacity of more than 3 Mt on a single strand. This paper introduces newest developments and features implemented in this latest ESP reference, such as the longest ESP caster ever sold with 8.5 t/min mass flow, the latest cutting edge split-core EMBR design and bulging compensation with the bender anti-bulging system. Special features of the rolling mill are the revolutionary inline work roll change system in the finishing mill, enabling to even double the current ESPs world-records regarding maximum rolled strip length within one TSCR sequence. Moreover, the Ultra Early Power Cooling system allows rapid cooling of thick gauges to coiling temperature already within the finishing mill before even reaching the cooling section in the run-out table, thus facilitating superior mechanical properties for demanding applications. These technological packages enable a fully endless production of the most challenging product mix ever seen on thin slab casting and rolling plants, while keeping the core features of Arvedi ESP lines like zero-carbon emission hot rolling and the well-known excellent coil quality. "

Bavestrelli , Giovanni, Tenova S.p.A., Italy

Co-Author: Christian Leoni, Tenova S.p.A.

Abstract: Metal scrap is a strategic raw material for the steel industry, accounting for a demand of nearly 30% of the metallic charge required for the global crude steel production, with the share that is foreseen to increase in the mid-term future. In scrap recycling steel mills, the scrap is typically loaded into an Electric Arc Furnace (EAF) in a controlled manner, tracking what goes in the charge mix and relating it to the quality of the liquid steel. Accurate tracking of scrap material from the time it enters the plant to the time it exits the furnace as liquid steel requires multiple technologies. The presentation describes the machine learning applications implemented in Ori Martin’s Steel Mill in Brescia, Italy, as part of the Lighthouse Plant “Acciaio_4.0” project in collaboration with Tenova. The project was selected by the Italian Smart Factory Cluster (Cluster Fabbrica Intelligente), on behalf of the Italian Ministry of Economic Development (MISE). The project created a Smart Factory in Ori Martin Steel Plant by integrating the enabling technologies of Industry 4.0 in the steelmaking process. The presentation focuses on the following solutions: • Automatic metal scrap classification • Identification of bulky material on Consteel® to prevent damaging EAF electrodes • Finding correlation between loaded scrap material and tramp elements in liquid steel • Optimization of charge mix with strict requirements on residual elements content • Rating of scrap suppliers based on production results The solutions involve the use of convolutional neural networks for image classification and various machine learning algorithms for process and sensor data.

Behrens, Holger, SMS group, Germany

Co-Author: Michael Brühl, Salzgitter Flachstahl GmbH • Oliver Meyer, Salzgitter Flachstahl GmbH

Abstract: Salzgitter Flachstahl GmbH, Germany, successfully commissioned the new Continuous Galvanizing Line (CGL) FV 3 for the production of galvanized high strength steel coils. The new line plays an important role in SZFG’s strategy and secures regional employment. Galvanizing ultra high strength steels pays in on light weight construction and sustainability. We also increase the vertical range of manufacture in our product mix. The line is supplied by SMS group and is located in Salzgitter, Germany. On July 23rd 2022, the first galvanized prime coil was produced. Besides the design and production of the mechanical equipment as well as the complete electrics and automation package, the furnace and process technology was part of the supply scope of SMS group, except the laser welder. Each year, 500,000 tons of galvanized steel strips for automotive structural components, white goods and industrial applications will be produced. Among other sophisticated technologies, the DREVER annealing furnace allows higher annealing temperatures, followed by faster strip cooling and longer dwell times. The configuration of the line as a whole also fulfills the structural as well as technical requirements to implement further innovative material concepts for the future. The new hot dip line can handle higher strength steels and support enhanced formability, and consequently also more complex component geometries. The continuous galvanizing line is equipped with a DUMA-BANDZINK air-knife system that ensure an optimum setting of the coating thickness plus a high surface quality of the zinc coating applied. The strip movement is stabilized additionally by the integrated electro-magnetic strip stabilization system. The main themes for this paper are the current and future product capabilities and the target market. Furthermore, the paper will emphasize the line concept and the process technology.

Beile, Hannes , tripleS GmbH & Co KG, Germany

Co-Author: Michael Hötzel, SHS - Stahl-Holding-Saar GmbH&Co.KGaA • Dirk Deckers, SHS - Stahl-Holding-Saar GmbH&Co.KGaA • Dominik Schöne, SHS - Stahl-Holding-Saar GmbH&Co.KGaA • Andreas Schneider, SHS - Stahl-Holding-Saar GmbH&Co.KGaA • Markus Abel, tripleS GmbH & Co. KG

Abstract: A comprehensive process transformation from a conventional integrated steel plant with blast furnace and converter into a modern electric steel plant with the aim of drastically reducing CO2 emissions is technically not easy and requires a careful consideration of all possible solutions. In particular, the effects on both - productivity and the quality of steel grades to be produced should not be underestimated or neglected. This article describes one of several possible solutions for the transformation of integrated steel plants: The implementation of an electric arc furnace - possibly together with a new reduction reactor to use direct reduced iron. Various considerations and challenges are identified in this paper, such as: Maintaining the original tapping weight or working with a different tap weight (partial tapping), is the necessary electrical connection capacity available or the given network stability sufficient and what solutions are available if not, is enough space available in a steel plant that has grown over decades for an integration of a new melting unit with reduction reactor, how will the raw material situation look like in 10 or 20 years? What is possible with an electric arc furnace? Is it realistic to produce actual steel grade qualities using an EAF as melting unit - and if yes - with how much virgin material? Does the possible or needed raw material scenario change the overall productivity? Can existing equipment in secondary metallurgy be reused or is there additional investment needed as well? All these questions and challenges will be explained and described in this article based on existing reference examples in cooperation with Stahl-Holding Saar for the locations in Dillingen and Völklingen.

Bernhard, Michael, Pohang University of Science and Technology, Korea, Republic of

Co-Author: Christian Bernhard, Montanuniversität Leoben • Sergiu Ilie, voestalpine Stahl GmbH • Youn-Bae Kang, Pohang University of Science and Technology • Won-Bum Park, Pohang University of Science and Technology

Abstract: Worldwide steelmaking industry targets a CO2 emission-free production of high-quality steel grades based on hydrogen reduction metallurgy and by using renewable energy sources for melting of recycled scrap in electric arc furnaces (EAF) and electric smelting furnaces (ESF). A serious issue for steelmaking plants in melting scrap materials is the unwanted accumulation of tramp elements in the liquid steel bath, e.g. Cu and Sn. Beside those elements, also other present impurities, e.g. S and P are known to may cause quality problems in continuous casting (CC) process, which is the dominating process to produce flat sheets and long product with an amount of 95 % of the annual steel production. The current status of developing a self-consistent thermodynamic database for tramp elements and impurities in steel is presented. The binary and ternary subsystems were modeled according to the CALPHAD-approach, enabling precise calculations of phase diagrams and thermodynamic properties of multicomponent steel. The Modified Quasichemical Model (MQM) was used to formulate the Gibbs energy of the liquid phase to consider the strong short-range ordering (SRO) tendency in M-S and M-P (M = Fe, Cu, Sn) melts. Ferrite and austenite solid solutions and intermediate phases were treated by the Compound Energy Formalism (CEF). Numerous stoichiometric compounds, e.g. phosphides and higher-order sulfides, were modeled stoichiometrically. In the present study, selected examples are demonstrated, linking the database to an in-house developed heat transfer model for the CC process to predict the solidification progress and possible defect formation, e.g. hot tearing. Furthermore, the database is applied to calculate solid/liquid phase equilibria in the Fe-C-Cu-Sn-S system with respect to liquid metal embrittlement in high-temperature ferrous processing. Finally, future requirements on experimental research and modeling work will be also discussed.

Berton, Julien, Vesuvius Europe, Belgium

Co-Author: Andrzej Warchal, Vesuvius

Abstract: Corrosion of zirconia containing refractory is one of the chronic issues that limits the service life of continuous casting nozzles resulting in shortening the casting time. In the present study, various degradation mechanisms of the lime-stabilized zirconia grains are discussed, focusing on microstructural and phase analysis. A classification of corrosion mechanisms is performed based on the phase assemblage and compositions of the reaction products resulting from the chemical interactions between mold-flux slag and zirconia containing refractories. A methodology was developed focusing on an experimental approach, thermodynamic modeling, and materials characterization techniques; this allows the development of new material composition and microstructure used in SEN/SES/MTSP sleeves. Several trials performed in the continuous casting operations demonstrate the benefit of new materials contributing to the longer service life of Vesuvius products generating a longer sequence length for the steelmakers. An industrial example performed in Tenaris Silcotub, Calarasi are given to describe the role of chemistry and fundamentals of chemical interactions between slag and refractory.

Beskow, Kristina, UHT Uvån Hagfors Teknologi AB, Sweden

Co-Author: Caroline Asplund, Uvån Hagfors Teknologi AB • Mårten Görnerup, Metsol AB

Abstract: The transformation of the iron- and steelmaking industry into a fossil-free production system is challenging as you need to maintain productivity and product quality throughout the transition. The transition will likely have to be carried out in several steps over time where parallel production in both old and new systems must be managed, and where it is important for the steel makers to always maintain the iron balance in the plant. The introduction of a metal granulation unit can facilitate the transition by enabling the iron producer to operate without constraints from downstream steel-making operations and handle large excess pig iron flows during the transformation. Granulation of iron with the GRANSHOT process has proven to be an efficient way to resolve difficulties in the iron balance in integrated steelmaking plants as it decouples the ironmaking and steel-making operations when required, producing a ready-to-use granulated pig iron product (GPI). The process is today widely used for rapid solidification of various types of metals and has been well established on the Indian market for handling large flows of excess pig iron from the BF. In the GRANSHOT process, liquid metal is transformed into solid granules instantly using a high-capacity water granulation process. The process can handle large capacities, up to 360 tph, and can be implemented adjacent to the existing BF allowing granulation directly from the torpedo. The granulated pig iron product is well suited for handling in many metallurgical processes and can be used either as a part of the internal feedstock in the existing/new plant or sold as a commodity to other operators, as valuable iron feedstock.

Bettinger, Dieter , Primetals Technologies Austria, Austria

Co-Author: Klaus Stohl, Primetals Technologies Austria • Bernhard Voglmayr, Primetals Technologies Austria • Harald Fritschek, Primetals Technologies Germany • Martin Schaler, Primetals Technologies Austria • Thomas Kronberger, Primetals Technologies Germany

Abstract: "Ironmaking facilities are very capital-intensive plants. There is a variety of smart solutions that provide guidance and support to avoid critical operational situations, warn in advance of system failures or equipment problems and support efficient maintenance. For new plants such advanced systems are frequently considered as essential, as they support cost efficiency and reduce the carbon footprint. However, also for plants in operation and in particular for plants at the end of the life cycle these systems provide important guidance to extend the lifetime avoiding disturbances, failures and critical situations. Various solutions from smart sensors to relevant aspects of process control and process optimization systems as well as predictive maintenance systems including digital assistants are presented. The possibilities to integrate legacy systems with advanced technologies and paths to an efficient interplay are illustrated and discussed. "

Bettinger, Dieter , Primetals Technologies Austria, Austria

Co-Author: Martin Schaler, Primetals Technologies Austria • Petra Krahwinkler, Primetals Technologies Austria • Christian Tauber, Primetals Technologies Austria • Angelika Klinger, voestalpine AG • Harald Fritschek, Primetals Technologies Germany • Christoph Feilmayr, voestalpine AG • Magdalena Schatzl, K1-MET GmbH • Clemens Staudinger, voestalpine AG • Ross Goldberg, Midrex Technologies, Inc.

Abstract: When using AI-based results for decision making or decision support, the reliability and a basic understanding of the underlying reasoning process is essential. Due to the involved complex metallurgy, thermodynamics and material parameters, modelling ironmaking processes with first principles methods is demanding. Artificial Intelligence (AI) and other data driven methods offer solutions for such complex systems. While AI- Algorithms are powerful, they tend to be black boxes. This can be overcome with Explainable AI and by considering Meta-Information. In this paper we present, how successful AI based applications for sinter plants, blast furnaces and direct reduction plants are built using such transparency techniques and how they are integrated into state-of-the art decision-support systems.

Bhattacharya, Saptarshi, M. N. Dastur & Co., India

Co-Author: Arnab Adak, M. N. Dastur & Co. • Atanu Mukherjee, Dastur Energy Inc. • Anindya Majumdar, M. N. Dastur & Co. • Arunava Maity, M. N. Dastur & Co.

Abstract: While global CO2 emissions are set to reach around 40.5 GTPA by 2022, the steel industry alone contributes 7-10% of the total emission. The CO2-intensive BF-BOF route of steel production is pre-dominant and will continue for some time. Decarbonization of BF-BOF is limited by the economics of multi-point post-combustion capture and technology to replace coal. Dastur has designed a novel solution integrating gas conditioning unit, carbon capture unit, and combined heat and power (CHP) plant. Gas conditioning unit helps to increase CO2 concentration to >30% and to capture >85% of available CO2 from a single source, enabling carbon capture technology to work efficiently with the lowest $/Te. Additionally, H2 can be recovered from the H2-rich fuel gas stream at a marginal cost of <0.5 $/kgH2. Since CO2 concentration is >30%, a wide range of technologies (from steam-based amine to all-electric PSA/Cryogenic) can be deployed depending on CO2 purity requirement, net CO2 reduction target, electricity, and steam cost. Even steam and power sourcing options could differ depending on available waste recovery options in existing steel plant operations. Additionally, the deployment of carbon capture along with H2 recovery can enable a circular green economy through utilization of CO2 /H2 in downstream industries like aggregates, methanol based chemicals, Enhanced Oil Recovery, etc. The incentives and support from governments can accelerate decarbonization of steel further. This paper discusses the key design aspects, policy support and techno-economics of different options.

Birla, Sheetal , Falkonry, United States

Abstract: Steel manufacturing processes are heavily instrumented, generating large volumes of automation data in the form of time series to the tune of over 5 million data points per second per plant. The time series data contain adequate information to represent the state of a physical system and production process at any given point in time. However, prevalent data-driven fault detection methods require significant setup efforts and expert inputs for modeling every known state of the system. This paper presents a novel self-supervised AI approach that does not require any setup effort and is capable of monitoring every existing process parameter and asset metric at high speed. Our approach utilizes a deep learning architecture based on Convolutional Variational Autoencoders (CVAE) that can start learning from small amounts of data to identify excursions, can automatically and incrementally learn as the underlying behavior of the asset changes and can process millions of measurements a second across thousands of time series. The automated time series AI informs plant operations of conditions that require human attention and provides diagnostics of underlying issues - leading to informed production and maintenance decision-making. Self-supervised AI overcomes the challenge the conventional machine learning method faces scaling to the needs of steel manufacturing by accommodating the challenges of constant equipment, environment, and product changes that hinder classical supervised learning methods. This paper will show this new AI in commercial steel manufacturing operations today.

Bissaker, Edward , University of Newcastle, Australia

Co-Author: Arash Tamesabi, University of Newcastle • David Jenkins, University of Newcastle • Merrick Mahoney , University of Newcastle • Bishnu Lamichhane , University of Newcastle

Abstract: Metallurgical coke microstructure is highly variable and consists of features at a wide range of length scales. Understanding coke microstructure using 3D micro-CT analysis is a valuable tool for producing coke that meets the requirements of future steel-making technologies. The two-point correlation and lineal path functions are microstructure descriptors that can be used to distinguish between microstructure formations. We present a scalable, histogram-free parallel method to efficiently compute the angularly resolved two-point correlation and lineal path functions for large 3D coke microstructure images. We compute coke feature length scales and representative volume elements for coke microstructure and provide a quantitative framework for investigating optimal microstructures corresponding to coke strength.

Björkvall, Johan, Swerim AB, Sweden

Co-Author: Patrik Strandberg, Outokumpu Stainless AB • Magnus Heintz, Swerim AB • Erik Sandberg Sandberg, Swerim AB

Abstract: Process models for the simulation and control of metallurgical processes have evolved rapidly in recent decades. Today’s state-of-the-art models are very advanced and can describe real-time chemical and physical phenomena in a straightforward way. However, uncertainties in raw-material properties (chemical composition, specific energy consumption, etc.) limit the process models’ ability to correctly describe the outcome of a particular heat or production sequence given a raw material mix and an operational procedure. Furthermore, the absence of measurements and control of parameters influencing the efficiency of the operational procedure (heat status, lining status, heel status, etc.) also contributes to uncertainties regarding the effect of using specific raw materials. This paper presents a method for supervising raw-material properties based on statistical evaluation of process model calculation errors concerning using different raw materials. The method is applied to detect and correct errors in the estimated chemical composition of charge materials in an electric arc furnace at a stainless-steel plant. A web-based tool for presenting alarms and alternative calculated chemical composition has been developed. Results show that during tests of this tool in industrial trials, the model calculation errors are reduced by 11-16 % by following the tool’s recommendations.

Björkvall, Johan, Swerim AB, Sweden

Co-Author: Dan Sandström, Swerim AB • Fredrik Sandin , Luleå University of Technology • Konstantinos Rigas, KTH Royal Institute of Technology • Jurki Pitkälä, Outokumpu Sweden AB • Niklas Grip , Luleå University of Technology • Nils Andersson , Swerim AB • Björn Glaser , KTH Royal Institute of Technology • Mikael Svensson , Uddeholms AB • Robert Vikman , Jernkontoret

Abstract: Measurement of the vibrations from metallurgical processes may give an indirect description of the process performance, thereby providing means to improve the overall process control. This approach is applied to the gas stirring of a ladle during vacuum treatment and the AOD converter in the present work. Analysing the vibration signals is challenging when vibrations from other processes surrounding the ladle or converter may affect the measurements. Even do vibration measured on ladles and converters has been reported before, the installation of vibration sensors must be adapted to plant-specific conditions as the temperature of sensors’ mounting positions and surrounding processes create vibrations. Positions for mounting the accelerometer were found close enough to monitor the vibrations from the process but at the same time at a position where the heat from the steel melt did not overheat the sensors. The positions of the accelerometers did not negatively affect the logistic of the steel production or the regular working procedures at the steel plants. Different mathematical algorithms were used to evaluate the recorded signals as machine learning, wavelet transform and the commonly used Fourier change. A comparison of the results from these different algorithms with available process parameters shows that the vibrations of the process correlate to the process performance. The analysed results correlate to the regulated gas flow at the vacuum ladle treatment and deviations most likely caused by fewer working porous plugs. In the AOD converter, the refining steps may be followed as different vibration intensities.

Bock, Sebastian, Rouge H2 Engineering, Austria

Co-Author: Gernot Voitic, Rouge H2 Engineering

Abstract: RGH2’s novel chemical looping based system can directly convert CO, CO2 and N2 rich blast furnace gas (BFG), coke oven gas (COG) and basic oxygen furnace gas (BOFG) into high purity H2 with inherent CO2 capture. The produced hydrogen can be utilized to substitute coal in the blast furnace and decarbonize steel plants, or to decarbonize plant-integrated heat and power generation systems. Based upon results in RGH2’s 100 kW OSOD On-Site-On-Demand demo plant (TRL 6) [1], the process produces high-purity H2 (>99.99%) and pure N2 (98.5%) as products, while sequestrating a carbon dioxide rich stream without energy penalty [2, 3]. In the specific case of nitrogen-containing gases (BFG, COG, BOFG), RGH2’s 3-step system enriches the CO2 content up to 50%. Only a downstream separation of nitrogen is required for CO2 sequestration up to 99% capture rate. Thus, the whole system can be an important building block to decarbonize the integrated steel plants. [1] Voitic G, Legerer C, von Hofen F, Beese-Vasbender P. Deponiegas zur Wasserstoffproduktion nutzen. GWF Gas + Energie. Sep. 2022; 163(Sep). https://gwf-gas.de/aktuelle-ausgabe-9/ [2] Bock S, Zacharias R, Hacker V. Co-production of pure hydrogen, carbon dioxide and nitrogen in a 10 kW fixed-bed chemical looping system. Sustain. Energy Fuels Mar. 2020; 4(3):1417–26. https://doi.org/10.1039/C9SE00980A. [3] Bock S, Zacharias R, Hacker V. High purity hydrogen production with a 10 kWth RESC prototype system. Energy Convers. Manag. Sep. 2018; 172(May):418–27. https://doi.org/10.1016/j.enconman.2018.07.020.

Boeke, Axel, Vallourec, Brazil

Co-Author: Savia Cristina Lacerda Poubel Pinheiro, Vallourec • Pedro Augusto Machado, Vallourec • Diego Bruno Santiago, Vallourec • Anderson José Santos, Vallourec • Axel Boeke, Vallourec

Abstract: The better EAF refractory performance can be achieved combining refractory materials and practices, metallurgy process parameters and proper slag composition. These 3 factors are well known as the success key for Steel Shop productions. Vallourec Brazil Steelmaking (VSB) counts on a very singular Consteel EAF which uses Hot Metal supplied by a Charcoal Blast Furnace. Nowadays, the Steel Shop is operating in 2 main recipes, which means with and without Hot Metal in the charge. So that, the attention to have an adequate slag chemical composition is in the routine bases for process feedback and control. Particularly, slag saturation and basicity had been more studied in this work guiding actions aiming to evaluate this control and benefits in the EAF refractory lifetime. The taken actions were defined and slag composition was evaluated using quaternary oxide system of MgO-CaO-FeO-SiO2, also analyzing the dual (saturated with CaO and MgO) and MgO saturated EAF slag chemistry comparing the base and period of trials indicated an effect increasing the refractory lifetime.

Dr. Bol, Luc, Director Optimization Iron and Steel, Tata Steel IJmuiden B.V., Netherlands

Co-Author: Jeroen Klumper, Director Sustainable Transition, Tata Steel Ltd • Mark Denys, Director Technology Transition / Decarbonisation, Tata Steel Ltd • Bart van der Meulen, General Manager Long Term Asset Strategy, Tata Steel Ltd

Abstract: Tata will transform its steelmaking facilities in IJmuiden, the Netherlands, to produce hydrogen-based green steel. To facilitate this multi-phased transformation, a Clean, Green & Circular strategy is being deployed, aiming at substantial improvements on these key themes. Clean: A significant decrease of environmental emissions (NOx, SO2, PM10, PAH, heavy metals) will result from the Roadmap+ programme and closure of existing assets in the new configuration. Reduction of emissions and nuisance in the nearby townships is targeted, for example, by dedusting and deNOxing the pellet plant, and by limiting emissions at the coke plants. Implementation timeline of these projects is 2019-2025 and investigations to further reduce emissions is ongoing. Green: Transition to green hydrogen-based steel making by replacing current blast furnace-technology with DRI-plants fed with blast furnace-grade pellets and using electric furnaces to produce hot metal. The target is to reduce CO2 emissions with 35-40% by 2030 (first blast furnace out of operation), 68-75% after 2035 (second blast furnace out of operation), to ‘zero’ in 2045. Zeremis Carbon Lite is the brand under which today low-CO2 mass-balanced green steel is supplied to customers. This product bridges the time gap to fully embodied decarbonised steel. Circular: An increased share of recycled steel is possible up to 30% by 2030 by increasing scrap input in the blast furnaces, converters and electric furnaces. This also includes an ambition for nearly 100% re-use of reverts on-site, for example by using Hisarna technology. The steel works in IJmuiden are well positioned for the green transformation, given that many success factors are in place or being developed. These include the proximity to off-shore wind farms and connection to a national hydrogen backbone currently under development, the existing deep sea port and railway connections, and a deep pool of young talent in schools, universities and technical institutes.

Bollmann, Joerg, John Cockerill, Germany

Abstract: Authors: Jörg Bollmann, John Cockerill UVK GmbH, Sergej Faber, John Cockerill UVK GmbH  Eco-friendly Acid Regeneration to help decarbonize the steel industry Acid regeneration systems are to reduce pickling process plants’ fresh acid demands and waste streams in general. With both, environmental protection and operating expenditure having substantially expanded in their importance, total acid regeneration plants based on the fluidized bed (FB) technology became today’s state of the art technology for premium steel suppliers increasingly committed to reducing their environmental footprint. In response to this trend, John Cockerill’s latest FB acid regeneration plants (ARP) come with an innovative and environmentally friendly concept, particularly in terms of emissions and waste energy recovery, along with smart and Industry 4.0 technologies. In combination with a perfectly matched tank farm guaranteeing the efficient management of all consumables, today’s highly automated ARPs allow the effective recycling of close to 100% of the spent acid generated in the steel manufacturing process, all while providing the highest possible process security, throughput, and plant availability. What is more, it is considerably reducing the steel complex’s annual dust and mist emissions and lowering or even eliminating other waste streams.  An eloquent testimony of the of the above, is the world’s largest ARP recently supplied to Chinese steel giant Baowu. It allows Baowu to achieve emissions that are only 1/3 of the very latest stringent Chinese standards. Namely the reduction of its steel plant’s dust emissions by 25 tons and its carbon footprint by a significant 4,800 tons per year. Simplified processes, such as quick-change spray/burner nozzles, our maintenance free venturi, our smart plant control system, or our Air Preheating System reducing fuel consumption and the CO2 footprint by a minimum of 10%, are only some of the many sustainable features that will be presented.

Bono, Riccardo, Università degli Studi di Milano, Italy

Co-Author: Marco Alloni, Prosimet S.p.A. • Riccardo Carli, Prosimet S.p.A. • Monica Dapiaggi, Università degli studi di Milano • Camilla Giada Baroni, Università degli studi di Milano • Andrea Bernasconi, Università degli Studi di Torino

Abstract: The change in structure in casting powders as a function of their basicity is well known to have important effects on their rheology, and therefore on their success in casting. Different compositions of casting powders were prepared in the form of glasses, by melting the appropriate mixture and fast quenching. The structure of the glasses was studied by means of neutron total scattering at the spallation neutron source ISIS (UK), at the beamline NIMROD [1]. Even though amorphous materials do not possess a long range order, they do have a short range order, whose variations may be responsible for the change in properties. The total scattering data were corrected for all the scattering not produced by the sample and Fourier transformed into a Pair Distribution Function, which provides peaks in correspondence of interatomic bonds. The figure shows an example for 4 of the samples, with a different fluorine content: sample 10 has the highest fluorine content, while sample 11 has the lowest. The shoulder in the plot, at about 2.3 Å, corresponds to the Ca-F bond length. The data were analysed through the software EPSR (Empirical Potential Structure Refinement) [2], which allows the creation of a 3D model of the system under study. From the model, various geometrical and structural information can be gained, such as the distribution of coordination numbers, bond lengths and bond angles. This allows to fully understand the subtle differences in the local structure of the glasses, and therefore to produce casting powders with a better performance. References [1] https://www.isis.stfc.ac.uk/Pages/nimrod.aspx [2] Soper AK (2010) EPSRshell: a users guide. ISIS DisorderedMaterial Group, Didcot

Boot-Handford, Matthew, Calix, Australia

Co-Author: Mark Sceats, Calix • Geoffrey Brooks, Swinburne University of Technology • Phil Hodgson, Calix • Andrew Okely, Calix • Matthew Gill, Calix • Thomas Dufty, Calix • Isis Rosa Ignacio, Calix • Bintang Ayu Nuraeni, Swinburne University of Technology • Andrew Adipuri, Calix • Yun Xia, Calix

Abstract: Calix is extending the application of its indirectly heated Calix flash calcination (CFC) technology to the decarbonisation of iron and steel production. The Zero Emissions Steel TechnologY (ZESTY) can be used to process low- and high-grade iron ore fines to a hydrogen direct reduced iron (H-DRI) product, avoiding the need for pelletisation or agglomeration. The small particle size range of the iron ore charge facilitates fast rates of metallisation allowing for significantly shorter residence times (in the order of 60s) and lower temperature operation than a conventional blast furnace such that the stickiness problem is avoided. Pilot-scale testing at Calix’s Centre for Technology Development in Victoria, Australia has shown that the ZESTY technology can produce a H-DRI product approaching commercial grade. The ZESTY technology is compatible with intermittent operation and can therefore be heated using renewable energy sources. ZESTY is targeting the theoretical minimum hydrogen use of 54 kg/t H-DRI as green hydrogen is used only as the reductant and is recycled in the process. Several scenarios are being explored for the downstream processing of the ZESTY DRI product including hot briquetting, direct flash melting and processing to green steel through integration with an electric arc furnace. Calix’s Low Emissions Intensity Lime and Cement (LEILAC) technology can be used to supply a zero-emissions lime fluxing agent to the EAF and other steel making processes. This paper will introduce the technology and discuss the status of ZESTY pilot testing and development.

Boyer, Michel, John Cockerill, Belgium

Co-Author: Nauwfel Amimi, ArcelorMittal Liège Jemeppe • Lionel Goiset, john Cockerill • Sergio Pace, Centre de Recherches Métallurgiques • Eric Silberberg, Centre de Recherches Métallurgiques

Abstract: In 2016, the ArcelorMittal Group became the first steelmaker to industrialize the vacuum deposition technology to galvanize steel strip. Known under the name of "Jet Vapour Deposition (JVD)", this new type of zinc coating technology in which a zinc vapor is continuously deposited onto a steel strip in a vacuum chamber. Compared to Electro-Galvanizing (EG) and Hot-Dip Galvanizing (HDG), the JVD technology allows to apply with high productivity single-side, as well as double-sided coatings with zinc thicknesses that can differentiate from one side of the steel to the other. Circumventing the major constraints of these conventional coating processes, the JVD technology allows for the optimal coating of Advanced High Strength Steels (AHSS). As such, the JVD technology prevents the hydrogen embrittlement identified as a major drawback of the EG process for the coating of AHSS. Additionally, the JVD technology also overcomes the negative influence of steel surface oxidation when using the HDG process for the coating of certain types of AHSS Today, after 6 years of production, the industrialization of the JVD steel coating line is a success. At the end of 2022, the JVD line produced over 800,000 tons of galvanized steel strip. To address all industrial constraints and make the JVD technology a high-speed deposition line exceeding the present limit of 200 m/min set by conventional EG & HDG lines due to physical limitations, numerous developments were necessary. An overview of these developments will be presented during the lecture, as well as the deployment of the JVD technology to other steelmakers worldwide through license agreements proposed by John Cockerill. Keywords Vacuum evaporation, Jet Vapour Deposition, automotive, industry, Zn coating, Advanced High Strength Steels, hydrogen, corrosion protection, environmentally friendly

Brandenburger, Jens, VDEh-Betriebsforschungsinstitut GmbH, Germany

Co-Author: Miguel Gutierrez, Universidad Politécnica de Madrid • Joaquin Ordieres, Universidad Politécnica de Madrid • Alessandro Maddaloni, Institut Polytechnique de Paris • Valentina Colla, Scuola superiore di studi universitari e di perfezionamento Sant'Anna • Vincenzo Iannino, Scuola superiore di studi universitari e di perfezionamento Sant'Anna • Christoph Schirm, Thyssenkrupp Rasselstein GmbH • Dirk Müller, Thyssenkrupp Rasselstein GmbH • Erwin Sirovnik, Thyssenkrupp Rasselstein GmbH • Andreas Wolff, VDEh-Betriebsforschungsinstitut GmbH • Ahmad Rajabi, VDEh-Betriebsforschungsinstitut GmbH

Abstract: Within the RFCS project DynReAct new concepts to improve the flexibility of production scheduling in flat steel production were developed and demonstrated at the tin-plate production site of thyssenkrupp Rasselstein in Andernach providing multiple production steps with free choice of multiple plants for production of a certain product. The selected concept follows a hybrid scheduling approach combining three planning levels with different planning horizons as well as planning accuracies to provide robust production plans on the one hand and flexible reaction strategies in case of unexpected events or decreasing plant performances on the other hand.

Brankov, Jelena, Carmeuse SA, Belgium

Co-Author: Dana Baricova, Technical University of Košice • Peter Demeter, Technical University of Košice • Jaroslav Legemza, Technical University of Košice • Róbert Findorák, Technical University of Košice • Branislav Buľko, Technical University of Košice • Sorinel Nafornita, Carmeuse SA • Francois Ponchon, Carmeuse SA

Abstract: An ultimate goal of oxygen steelmaking process is formation of a basic slag using fluxes (lime, dolime) to remove impurities, like phosphorus and sulphur. Fluxes dissolution efficiency is important to achieve basic slag at the early stage of the process and protection of refractory lining. Limiting step in the slag formation process in the BOF represents lime dissolution kinetics in the primary acidic slag. Lime for the steelmaking process must be soft-burnt, as only this type has a high reactivity - ability to transition to the slag phase. Experimental work was carried out in a Marsh furnace to determine the mechanism of lime dissolution in the slag. Dissolution rate of different types of lime (soft, medium, and hard-burnt lime) in the typical BOF slag were compared. It has proven an excellent solubility for the soft-burnt lime, which is related to its high reactivity and a lower solubility for the hard-burnt lime. After determining the mechanism of lime dissolution in the steel slag, high-temperature experiments were performed in the induction furnace. Results were used to quantify the level of lime dissolution in the steel slag, compare it with a standard lime reactivity measurement, and for development of Value in Use Model. This in-depth study was conducted to understand the importance and to evaluate the influence of lime characteristics on BOF steelmaking process and their quantification through total cost of ownership. Besides lime dissolution, thermodynamic and the fluid dynamic approach was used, together with mass and heat balance. Value in Use Model proves the importance of lime characteristics and its impact on steel cleanliness, metallurgical results, productivity, and total cost of steel production including notably energy and CO2 balance. Model can calculate the savings and cost benefits for a given inputs, including lime and dolime,and operating parameters for respected case.

Brasjen, Berend, Tata Steel IJmuiden B.V., Netherlands

Abstract: At Tata Steel's European production lines for continuous annealing and hot-dip galvanising, strip temperature is controlled by an in-house developed, non-linear model predictive controller. Every incoming strip is assigned its own set of target temperatures, commonly referred to as the temperature recipe, based on its chemical composition, dimensions and special requirements. Over the years, the controller has demonstrated its value by maximising speed of production whilst minimising deviations from the recipe, especially during transitions between strips with different recipes. This ensures maximum uniformity of the time-temperature path over the length of each strip, which translates to maximum homogeneity of product properties (mechanical, chemical or otherwise) if these are uniform at the start of the annealing process. However, if the initial product properties vary between several strips within the same order, or even along the length of a single strip, these heterogeneities will not be fully alleviated by keeping the process temperatures close to recipe values. In order to improve the uniformity of the final product properties after annealing, we have developed an application capable of determining a tailored set of temperature targets, based on incoming strip properties. The application uses material models to determine which target temperature adjustments are expected for a specific strip, so as to provide optimum homogeneity of final product properties. The resulting tailored recipe is then fed back to the temperature controller to be assigned for this specific strip. In this way, maximum use can be made of the annealing line capabilities to achieve our customers’ target material properties with tighter tolerances.

Breuer, Michael , SMS group, Germany

Co-Author: Falk Töpfer, SMS group

Abstract: When speaking of cold strip rolling, especially carbon strips, normally final gauges between 1.5 mm and 0.40 mm are referred to. Cold rolling of thinner strips keeps special challenges for the plant technology and the process control. In addition to the targeted final thicknesses, it is also important to attain the strip quality and the required product properties, such as flatness or surface quality. Rolling jobs which involve special challenges are preferred performed in reversing mills because here the rolling process is more manageable and a strip break has less impact on the production. The limitation on reversing cold mills, however, is the limited production capacity which, in the case of single-stand mills, is around 300,000 tons per year and in the case of two-stand Compact Cold Mills, around 600,000 tons, depending on the processed strip widths and strip gauges. A tandem mills productivity is even higher at a better yield rate together with a more simple process steps. There are regions on the world market - and this includes the Asia/Pacific region - which have a very high demand for cold-rolled thin strip in a thickness range of 0.50 mm to 0.15 mm. Two of the main applications for this material are roofing and packaging. With the capacities installed in this region alone, the demand cannot be met completely. SMS group supplied two coupled pickling and tandem roll mills especially for this demand. This paper provides an overview on the challenges and experiences we made during commissioning of this two PLTCMs. Focus is on mechanical equipment and process control items.

Breuer, Michael , SMS group, Germany

Co-Author: Georg Padberg, SMS group

Abstract: The flat product market increasingly demands hot strip for direct further processing. Thin hot strip is applied in many industries. In general: all cold rolling applications that do not require heavy deep drawing operations and a high surface quality can be replaced by thin hot strip. Plant owners may optimize or reduce the process steps. Cold rolling passes and/or intermediate annealing can be omitted or even be canceled completely, resulting in increased profitability and energy savings. There are special hot mill concepts on the market, which focus specifically on the thin strip demand. However, they come with a drastically reduced product range and weakened flexibility to react on process disturbances. The process control in a hot strip mill has to face special challenges arising with the production of strip with thicknesses of less than 2 millimeters. Some of the typical challenges that occur during thin-strip rolling are: • Ripped strip end • Pinching caused by unflatness • Steering control • Increased roll wear • Save coiling • Speed limitations These challenges may cause a deterioration of the yield due to increased off-gauge lengths and the number of cobbled coils. SMS group is aware of these challenges and offers customers a “toolbox” to improve the behavior of the hot strip mill when “going thin”. The “toolbox” consists of mechanical and automation equipment and software. Beside fast mechanical actuators, a number of strip guiding systems are part of the toolbox. The strip steering control module has an important task in achieving a straight transfer bar and avoiding cobbles and ripped strip ends. Also, the operator is released from the leveling task and can focus on the rolling process. Beside strip steering control, the paper will give insights into other related topics and their impact on the production of thin gauges. Some operational results will be presented as well.

Breuer, Michael , SMS group, Germany

Co-Author: Georg Padberg, SMS group • Wolfgang Fuchs, SMS group • Heiko Reichel, SMS group

Abstract: CO2-neutrality is the imperative of this time to protect and preserve our environment. The steel industry is particularly focused on it, because by its very nature the manufacturing processes are energy-intensive. For steel manufacturers, this requirement leads to strategic reorientation. As plant supplier, SMS group is challenged to develop and offer innovative solutions right across the entire process chain. One challenge is to identify and utilize all energy saving potentials in the production process. The second and major task is to substitute fossil fuels by electrification and by use of green fuels. The hot rolling process is comparatively energy-intensive. The largest consumer of energy is the heating process. A major focus thus needs to be placed on the interface between the upstream processes and the hot rolling process, where optimization measures for energy saving can be made. Also for the hot rolling process itself, it is important to evaluate each individual energy consumer for his optimization potential. For some process stages and components there are already proven solutions which gain new significance in the context of fossil free production and to tap into their inherent potential. One example is the installation of mandrel-less coilbox in the roughing mill area. A coilbox comes with numerous advantages and improves the process control. However, a coilbox reduces the overall plant length and the energy consumption in the finishing mill. Another example is smart descaling, which takes place in the roughing and in the finishing mill area. Smart descaling means width and steel-grade dependent descaling. The water pressure and the water volume are specifically controlled and applied, resulting in water and energy savings. These are just two examples, among other things - including new developments, which we intend to evaluate as part of the paper with regard to their energy saving potential.

Breukelman, Hubert, Tata Steel IJmuiden B.V., Netherlands

Co-Author: Maria Martinez Pacheco, Tata Steel Nederland Technology B.V

Abstract: The increasingly high demands on European integrated steelworks in terms of sustainability and circularity necessitate the reduction of Greenhouse gas emissions from fossil sources like coke breeze, and require an increase in use of internal waste streams. In this paper, the effect of iron- and steelmaking by-products on sinter productivity and quality are assessed using sinter pot trials. Furthermore, a selective preparation method, the Composite Agglomeration Process (CAP), was used to improve the process characteristics of carbon-rich by-products. This method entails pre-pelletisation of fine-grained components of the sinter mixture on a balling disc, followed by a secondary mixing with the coarse-grained components. To assess the use of the carbon-rich by-products, sinter pot trials were carried out with low (5-10%) and high (15-20%) total by-product content, using the CAP method and conventional granulation. Process monitoring shows that flame front characteristics are strongly influenced by the addition of high carbon by-products when added using conventional granulation, presumably due to combustion kinetics differing significantly from coke breeze. This effect is also observed in the CAP trials, where further effects are observed due to significant differences in sinter bed permeability. The sinter pot trials clearly show that by The CAP method, the replacement factor for coke breeze can be increased, and deterioration of sinter quality caused by high by-product utilization is reduced.

Brhel, Jaroslav, HTT Engineering spol. s r.o., Czech Republic

Co-Author: Andrea De Vito, Rina Consulting – Centro Sviluppo Materiali S.p.A • Daniele Gaspardo, Pittini S.p.A. • Matteo Chini, Pittini S.p.A.

Abstract: Pittini plant Ferriere Nord is one of the major Italian plants operating 150t EAF. Within European Retrofeed project https://retrofeed.eu/, some new developments were tested in 2022. These include new EAF burner and modified injection system for utilization of alternative materials such as fine polymers and granulated tires as source of chemical energy in EAF, partially replacing natural gas and carbon. The paper will describe equipment and process development made and introduce some initial obtained results and experience.

Brhel, Jaroslav, HTT Engineering spol. s r.o., Czech Republic

Co-Author: Pierre Guillaume, ArcelorMittal Industeel Belgium

Abstract: Arcelor Mittal Industeel plant in Charleroi produce special high quality steels including stainless steel grades. Chemical energy package including burners and carbon injection lances on its 200t EAF has been revamped in 2022 resulting in improvement of energy efficiency and yield for all produced steel grades. The paper will discuss project execution, new equipment layout and performance as well as operating experience comparing results before and after revamping both for carbon and stainless steels.

Brune, Tobias, SMS group, Germany

Co-Author: Yannik Wilkens, SMS group • Peter Weiland, SMS group

Abstract: SMS group supplies plant technology for the production of high-quality metal powder for Additive Manufacturing (AM) and other technologies. Cost-effective and high-quality powders will be one of the main drivers for the development of metal AM towards a sustainable industrial technology. By operating a gas atomization plant (VIGA - Vacuum Induction Gas Atomization) integrated in the SMS 3D-Test Center, the SMS group has optimized the classical powder production for the requirements in AM over the last years. In addition to conventional gas atomization plants, the SMS group, together with a customer, has developed another innovative powder production process. The conventional batch-wise process is transformed into a continuous process. The continuous powder production plant enables cost-effective and large-scale production of up to 4,000 tons per year. Compared to the traditional gas atomization process the capacity is increased by a multiple. Production costs for spherical, high-quality metal powders are significantly reduced. The increase in capacity results in enormous economies of scale. Set-up times, melting and cooling times are reduced. In the new process developed by SMS group, two Vacuum Induction Melting (VIM) furnaces continuously hold liquid melt, which is atomized successively through the nozzle. The nozzle can be exchanged during operation. Melting is done under vacuum to guarantee highest quality levels like in the conventional process. In addition to the VIM route, where pure scrap is used as feedstock, the new process can also work with an existing liquid material supply. A metallurgical route with basic scrap as feedstock is also possible.

Brunnbauer, Robert, S+P Samson GmbH, Germany

Abstract: In the steel industry, things can get pretty hot in a rough and dirty environment. To ensure reliable material tracking, optimum warehouse organization and smooth shipping logistics under these adverse conditions, modern and efficient identification solutions are required - ideally automated. This is exactly where S+P Samson has its roots and where it has acquired over 40 years of experience. The robust GRAPHIPLAST® data carriers have been customized for the requirements of the steel industry and can be used either as a self-adhesive label or a hangtag. The new ID4track® RFID High Temperature hangtag is a polymer film with a 1-side heat-resistant coating. The material withstands a continuous load up to 360 °C / 680 °F, for a short time up to max. 450 °C / 842 °F and is weather, aging and scratch resistant. Its resistance to ultraviolet radiation makes it suitable for outdoor use. A protective shield over the RFID inlay ensures trouble-free use in drying processes with high temperatures. The tags are attached with metal clips. Read range at non-metals is up to 8 m and up to 5 m at metals. The new ID4track® RFID High Temperature Tag consists of three main components: 1. tag material: GRAPHIPLAST® 7377.140 with a tear-out strength of 140N 2. transponder: bonded on PI substrate and works in the UHF frequency band of 860 to 960 MHz (ETSI and FCC, ISO/IEC 18000-6C). It is based on the chip NXP UCODE 7xm (EPC: max. 448 bit, TID: 96 bit factory locked, User memory: 2048 bit) 3. protective heat-shield: also GRAPHIPLAST® 7377.140 The RFID solution for your processes in the steel industry and its difficult industrial identification requirements.

Bryce, Christopher, Vesuvius UK, United Kingdom

Abstract: The challenge in front of us with this prototype system has been significant, not only how to increase the speed of repair material delivery into the hot furnace, but more significantly, to do this immediately after the furnace has been emptied of molten slag. Successful repairs have taken place with lining temperatures measured by digital pyrometry at +1600 °c. Our internal objective to deliver one tone of gunning mass in less than five minutes has been exceeded consistently reducing the overall repair schedule time which typically takes up to twenty minutes after a furnace cooling down period. High speed gunning has not only achieved a record average repair gunning rate of 244kg/minute. We have achieved this consistently without any cooling down period. High speed gunning likens itself to a formula one racing car strategy for steelmakers, with fast set up, repair, and removal of equipment, all aspects of the system from material formulation to the equipment specification is designed to minimize repair time. The total repair downtime of 10 minutes has been achieved. Allowing the steelmaking cycle to restart immediately. A recent 5-day study of the technology in a 325t BOF Furnace has delivered a repair area lining thickness increase of 147mm from the high-speed application between 1776 to 1851 lives of the furnace, during this period ten high speed repairs took place. The repair speed, lining thickness increase, and overall time saving has Exceeded the steelmakers expectations of what is possible in the lower cone area of the hot BOF furnace. In the following paper we will present the system design advantages and share the results from industrial trial of the system.

Bulzak, Tomasz, Lublin University of Technology, Poland

Co-Author: Konrad Lis, Lublin University of Technology • Łukasz Wójcik, Lublin University of Technology • Grzegorz Winiarski, Lublin University of Technology

Abstract: Cross wedge rolling is a technology used to produce preforms used in drop forging processes or axle and shaft forgings. The cross wedge rolling process is carried out using flat tools or rolls with wedges that, by cutting into the billet, progressively give it the shape of a forging. The technology has a lot of advantages, the most important of which are the high process efficiency and good accuracy of the forgings produced. A significant limitation of the use of cross wedge rolling technology, in particular for the production of responsible parts, is the adverse phenomenon of material cracking in the central part of the forgings during rolling. The advantages of cross wedge rolling can be exploited in the production of railway axles, which are currently produced by less efficient and less accurate technologies. Unfortunately, the phenomenon of material fracture introduces serious limitations to the implementation of this technology in industry. The paper presents the results of a study with the primary aim of eliminating material fracture. Numerical simulations using the finite element method were carried out prior to the experimental tests. Using cross wedge rolling technology and specially designed tools, a railway axle forging was rolled at various temperatures. The results of this study confirmed that the rolling temperature has a significant effect on the material fracture phenomenon in the cross wedge rolling process. By increasing the rolling temperature, the material cracking phenomenon can be eliminated.

Büttgen, Armin, thyssenkrupp Steel Europe AG , Germany

Abstract: New process for hot rolling of high-strength pipe steels A. Büttgen, A. Kern, C. Konrad, A. Latz, C. Straub thyssenkrupp Steel Europe, Duisburg Due to the ecological and economic situation worldwide and the resulting steadily increasing demand for pipelines, more and more efficiency of the hot strip manufacturing process to produce pipe steels is required. To achieve the demanding mechanical properties of modern pipe steels in terms of strength and resistance to brittle fracture, a very fine ferritic microstructure is crucial. So far, thermomechanical rolling with final rolling temperatures as low as 780 °C has been the method of choice. Unfortunately, this process reduces the plant performance due to noticeable delay times between roughing and finishing. Moreover, inhomogeneities become more pronounced along the strip, which deteriorates the performance of the product. To overcome this problem, a new rolling strategy for high-strength pipe steels was developed supported by numerical modelling of the microstructure and mechanical properties. In conjunction with a simultaneous adjustment of the cooling strategy with increased cooling rates, roughing and especially finishing can be carried out more gently. The resulting ferritic or ferritic-bainitic microstructure leads to at least a consistent product performance. This paper gives an overview on the characteristics of the new rolling strategy and presents first production results: The operational rolling results of pipe grade X70 show that the novel process leads to an increase in the performance of the hot strip mill compared to classical thermomechanical rolling. At the same time, the system load was significantly reduced and the product performance in terms of strength and resistance to brittle fracture was kept constant.

Cairoli, Giovanni , SMS Concast AG, Switzerland

Co-Author: Stephan Feldhaus, SMS Concast AG • Pierpaolo Rivetti, SMS Concast AG • Marco Abram, SMS Concast AG • Zhang Jun, SMS Concast AG • Gang Qian, Jiangyin Xingcheng Special Steel Works Co. Ltd • Yuhui Chen, Jiangyin Xingcheng Special Steel Works Co. Ltd • Xiaohong Xu, Jiangyin Xingcheng Special Steel Works Co. Ltd • Guoqing Xu, Jiangyin Xingcheng Special Steel Works Co. Ltd

Abstract: In order to drastically reduce carbon dioxide emission and realize carbon neutrality, and fulfill the high demand of materials for the wind turbine market which delivers clean renewable energy, with the aim of producing superior as-cast products with high yield and low energy consumption, Jiangyin Xingcheng Special Steel Works Co. Ltd (part of CITIC Pacific Special Steel Group Co., Ltd.) decided to install a jumbo round bloom caster in their premises in Jiangyin City, P.R. China. The caster has been co-designed, supplied and commissioned by SMS Concast AG (part of SMS Group). It has been put into operation in the last quarter of 2021, with the world’s first cast of Ø1200mm round section on the 13th of December 2021. The section size range goes from Ø800mm to Ø1200mm round sections. Advanced technological packages such as Dynamic Mechanical Soft Reduction, three electromagnetic stirrers and optimized secondary cooling will assure the highest bloom quality required by the demanding product mix. Tailored engineering solutions such as cartridge molds, common MEMS, adjustable Strand- and Final-EMS and chain dummy bar system able to cope with the jumbo formats will allow to have a robust and flexible caster, minimizing downtimes. Electromechanical stopper, hydraulic oscillator, on-line solidification model, L1 and L2 automation are completing the Caster scope of supply in order to achieve a reliable and controlled process. Special design solutions as well as first quality results after Caster commissioning are presented in this publication.

Cameron, Ian, Hatch Ltd., Canada

Co-Author: Mitren Sukhram, Hatch Ltd. • Nicholas Aubry, Hatch Ltd. • Takshi Sachdeva, Hatch Ltd. • Pauli Baumann, Hatch Ltd. • Sa Ge, Hatch Ltd. • Terrance Koehler, Hatch Ltd. • Richard Elliott, Hatch Ltd.

Abstract: Many steel producers are focused on replacing their blast furnaces with direct reduced ironmaking (DRI) as a greenhouse gas (GHG) reduction strategy. While several producers have announced plans to smelt DRI with a standard electric arc furnace (EAF), others are considering electric smelting furnace (ESF) technology to produce hot metal suitable for basic oxygen furnace (BOF) steelmaking. Drivers for the adaption of the DRI-ESF-BOF route include the ability to use traditional higher gangue iron ore, slag valorization for cement manufacturing, better impurity control such as nitrogen and phosphorous in the liquid steel and to avoid stranding existing BOF steelmaking assets. Most producers have selected the DRI route for its potential to start with the well-understood natural gas-based technologies and then transition to greater amounts of green hydrogen as this becomes available. Carbon in hot metal will be essential for the ESF and BOF stages of the new process route even as natural gas is replaced with hydrogen. How best to carburize the ESF hot metal when iron ore is reduced to metallic iron using hydrogen is an open opportunity for technical innovation. Little attention has been paid to the re-use of the CO and CO2 rich gases generated from the ESF and BOF to carburize the DRI prior to smelting. The authors will present technical approaches to re-use these off-gases in-plant to minimize the GHG emissions from the DRI-ESF-BOF value chain, especially in the context of a transition to green hydrogen-based iron ore reduction. Needed technologies such as effective gas separation, methanation, reverse water gas shift, and carbon cycling will be discussed, and a new integrated flow sheet will be proposed.

Cardoso, Pedro, Vesuvius Sp.z o.o., Brazil

Co-Author: Lucio Mascarenhas, Vesuvius • Eduardo Duarte, Vesuvius • Paulo Teixeira, Vesuvius • Franz Ramstorfer, Ternium • Giovani Delfim, Ternium • Moises Miranda, Vesuvius

Abstract: In the light of the Industry 4.0, the Robotic Process Automation (RPA) is being considered as new wave of the future technologies, connecting several fields of engineering as mechanical, electronic and automation. Following this trend, the human processes in the steelmaking plants, whose level of danger is one of the highest in the industrial sector, are beginning to be oriented towards being automated. The main advantages in the use of robot manipulators in this industry are the increase in the safety of the operators, in the quality of the process and in the production. However, the implementation of robot manipulators in the steel industry has several challenges that result in the low rate of use of this system in this segment of the industry, as an example, exposure to high temperatures, high concentration of dust and particulates and adaptation to the original layout of the machine, whose system will interact. It's shown the increase of productivity, safety and product quality of robotized tundish operations in continuous caster operation1. The objective of this paper is to present the implementation and the results of the robotized tundish operations focused on the ladle exchange operation, in which it is notably the most critical moment of the continuous casting. In addition to ensuring the operator's safety, the increase in quality is proven by the reduction of N2 pickup2 in operations using the robotized tundish compared to conventional operations.

Cascino , Carlo, SMS Concast AG, Switzerland

Co-Author: Marco Abram , SMS Concast AG • Andrea Lanari , SMS group • Filippo Verlezza , SMS group

Abstract: Sustainability and lowest carbon footprint with high productivity are the current and future challenges in the steel industry for the production of long products. The CMT® (Continuous Minimill Technology) process developed by SMS group is an inline endless casting and rolling process designed to reach these goals. A low emissions steelmaking facility supplies liquid steel to a high-speed casting machine directly feeding the rolling mill, eliminating the traditional fossil fuel fired re-heating furnace. The pairing of flat bath continuous scrap melting together with direct rolling of rebar or very compact coils concept drastically reduce up to 70% the overall direct emission on site of greenhouse gases, increasing the environmental sustainability of the CMT. Liquid steel is produced and refined by an advanced steelmaking plant, based on Allcharge® design coupled with AURA® IGBT electronic power modules, ensuring the lowest environmental impact in terms of CO2 and NOx emissions and opens the door to connection to renewable power. As the CMT concepts require high casting speed, special attention must be paid to mold and strand guiding design (SMS Concast CONREX technology), mold oscillation (SMS Concast CONDRIVE® electromechanical oscillation) and secondary cooling. The flexible CMT process can be designed for a wide range of products, from straight rebars to Vertical Compact Coils up to 8 tons (VCC). Integrated L1 and L2 automation systems, managing all production process aspects from the scrap yard logistics to the mill finishing area, as well as covering maintenance of the plant are also a key element to the efficient and cost effective production. This paper will highlight the main environmental advantages of this technology, as well as the various concepts for different range of production.

Dr. Castagnet, Jean-Frédéric, Director Technology & Innovation, Georgsmarienhütte Holding GmbH, Germany

Abstract: Global climate change is due to the very sharp increase in CO2 emissions over the past 60 years. The steel industry, being one of the largest CO2 emitters, must therefore significantly reduce its CO2 emissions, in order to meet the 1.5° Paris Climate Agreement' s target. The GMH Gruppe is already playing a pioneering role in the decarbonization of the industrial value chain. For more than 25 years, this medium-sized group of companies has relied on steel production in electric arc furnaces. By using this technology, the CO2 emissions of crude steel are already significantly below the industry average, at 0.4 tones per 1 tone of steel. Their long-term goal is to produce steel in a climate-neutral way by 2039. As an interim step, emissions are to be halved by 2030. There are a number of decisive steps for achieving climate neutrality in electric steel production, such as the use of green electricity in production which can significantly reduce CO2 emissions. Other measures include, the use of biogenic carbon carriers as well as the use of hydrogen instead of natural fossil gas. The use of by-products such as slag or waste heat also makes a decisive contribution to decarbonization. In the long term, it is crucial to look at the entire supply chain, which is why the focus on upstream emissions (so-called Scope 3) is also becoming increasingly relevant.

Castagnola, Cristiano, Paul Wurth Italia S.p.A., Italy

Co-Author: Teresa Annunziata Branca, Scuola superiore di studi universitari e di perfezionamento Sant'Anna • Valentina Colla, Scuola superiore di studi universitari e di perfezionamento Sant'Anna • Alice Petrucciani, Scuola superiore di studi universitari e di perfezionamento Sant'Anna • Antonella Zaccara, Scuola superiore di studi universitari e di perfezionamento Sant'Anna • Ismael Matino, Scuola superiore di studi universitari e di perfezionamento Sant'Anna • Luca Spadoni, Paul Wurth Italia S.p.A. • Lorenzo Micheletti, Paul Wurth Italia S.p.A.

Abstract: In the framework of European Green Deal, steel companies are facing a deep transformation towards ever more carbon-lean processes. Besides studies focused on direct reduction processes, several research works deal with the decrease of the impact of existing routes, for instance, by decreasing the use of fossil fuels. Effectively, the transition from standard integrated route to a direct reduction-based route requires efforts and time but, considering the climate changes and the environmental issues, it is of extreme importance to reduce urgently the greenhouse gases and hazardous air pollutant emissions. In this way, during the transition, brownfield processes can contribute actively and gradually to the Green Deal. This is the context of this study, which focuses on the investigation and development of a process allowing a further treatment of blast furnace gas for ensuring a reduction of NOx when it is used in hot blast stoves and, in particular, at high temperatures. Pushing hot blast stoves at higher temperatures means obtaining higher temperatures of preheated air to be injected in blast furnaces, decreasing coke demand and, consequently, CO2 emissions. The presented treatment is based on a spray-scrubber whose main aim is the reduction of cyanide compounds in blast furnace gas due to their direct link with NOx emissions. The scrubber also allows chlorides removal by reducing corrosion problems. Auxiliary to the gas washing process, a H2O2-based water treatment was invelstigated to reduce the content of cyanides in the blast furnace gas washing water to allow its recirculation and to make purges suitable for discharges. Different kind of analyses were done to develop the process and prove its effectiveness and potential, including literature and data analyses, development of ad-hoc models for scenario analyses, laboratory tests and optimal design of process and unit operations.

Cejka, Julian, Montanuniversität Leoben , Austria

Co-Author: Bernhard Sammer, Montanuniversität Leoben • Nikolaus Preißer, Montanuniversität Leoben • Gerald Klösch, voestalpine Stahl Donawitz GmbH • Susanne Katharina Michelic, Montanuniversität Leoben

Abstract: The demand for higher scrap rates in European steel plants leads to increased amounts of tramp elements in steels, like copper, molybdenum and tin, and their further enrichment due to lack of possibilities for their removal. While other elements, especially the 16th group of the PSE like oxygen or sulfur, are well investigated, the effect of tramp elements on interfacial properties remain unclear. These phenomena are of high importance for different multiphase processes. While poor wetting of inclusions by steel at refining steps is preferred to transport inclusions from liquid steel to the slag, it can be detrimental in continuous casting due to the increased deposition of inclusions in the submerged entry nozzle and finally resulting in clogging. In this work an industrial medium carbon steel has been alloyed with ultra-pure tramp elements, namely Cu, Mo and Sn. The amounts of these increase gradually from standard-confirm levels up to values supposed to occur in future steel scraps. These samples are studied by means of drop shape analysis to quantify the influence of these impurities on the wetting angle on dense alumina and zirconia plates. With this method temperature and time dependency can be observed. Furthermore, the oxidic substrates and steel droplets are examined by metallography and SEM/EDS after the experiments to determine possible reactions. Thermodynamic calculations using FactSage are additionally applied.

Chattaraj, Soumi, Tata Steel Ltd, India

Abstract: Chloride in sinter comes from raw materials including iron ores, reverts, Coke breeze and fluxes. Taking into account the thermo-chemical properties of the chloride compounds, sinter product contains less chloride (~20%), but gets accumulated to a greater extent in the waste gas dust. As the waste gas dust (ESP dust) is reused in the process, progressively chlorine enrichment happens. Literature suggests, the alkaline chloride raises the electric specific resistance of dust surface and thereby decreases the electrostatic precipitator (ESP) performance. With continuous increase in the chloride value of dust, ESP performance deteriorates, thereby increasing the dust content in the stack gas. Chloride level increases with field number of ESP as more finer and more chlorine concentrated dust is captured in the last fields. Alkali –K2O & Na2O follows the same trend: more alkali in the final field as alkali remains mainly with finer dust (Cl remains mostly as alkali chloride). To combat the chloride effect there is a study and a trial taken to lessen chloride input to the system by evacuating the “most concentrated” ESP dust of last field and breaking the enriching chloride cycle. Study shows that weekly or in certain frequency bleeding of the last of field dust for a day will help to reduce the chloride load . Our observations shows with this initiative, there is a significant amount of reduction in dust content in stack gas. To reutilize the dust, cleaning this extracted dust is also carried which shows very promising result.

Cheremisina, Elizaveta, K1-MET GmbH, Austria

Co-Author: Johannes Schenk, Montanuniversität Leoben • Emmanuel de Bilbao, CNRS, CEMHTI, University of Orleans • Zheng Zhang, CNRS, CEMHTI, University of Orleans

Abstract: Density, surface tension and viscosity of the slag are key properties in steel refining. The accurate measurement of these properties is required for better process control of metallurgical operations. Aerodynamic levitation was employed to derive density, surface tension and viscosity of CaO-SiO2 and CaO-SiO2-Fe2O3 slags under contactless conditions. The levitation experiment was carried out under mixture of argon (80%) and oxygen (20%) gas atmosphere in the temperature range between 800 °C and 2000 °C for the density and 1500 °C and 2000 °C for surface tension and viscosity measurements. The quenched slag samples were analysed by Raman spectroscopy to provide information on the anionic structure of the silicate slag. It was observed that the addition of Fe2O3 to the silicate did not affect surface tension, while it influenced the density due to the reduction of non-bridging oxygens and viscosity due to the increase in the polymerization degree, especially for high silica-containing slag.

Chiarullo, Enzo, Tenova S.p.A., Italy

Co-Author: Enrico Malfa, Tenova S.p.A. • Mattia Bissoli, Tenova S.p.A. • Sergio Porisiensi, Pittini S.p.A. • Marta Guzzon, Tenova S.p.A. • Marco Fulgosi, Pittini S.p.A.

Abstract: Valorization of LF slag: the Pittini Group tests Tenova's air granulation process S. Porisiensi, M. Fulgosi – Ferriere Nord S.p.A. M.Guzzon, M.Bissoli, E.J.Chiarullo, E. Malfa - Tenova S.p.A. The Pittini Group has historically been active and committed to the reduction and valorization of steelshop residues and, in particular, Ferriere Nord plant in Osoppo was the first in Europe in 2000 to implement the recycling of LF slag by injecting it into EAF in lime replacement. In last two years, the Pittini Group tested, at Acciaierie di Verona and Ferriere Nord sites, an industrial-scale pilot plant for the valorization of the ladle furnace slag through an air granulation process developed and designed by Tenova S.p.A. Tenova developed a methodology for the design of dry slag granulation process based on Computational Fluid Dynamic modelling validated by the laboratory testing in a pilot plant. The present work shows the results of the dry slag granulation industrial testing, performed at Ferriere Nord plant, their consistency with the Tenova methodology in the process design together with validation through testing at laboratory scale pilot plant facility. In addition, the first study for the industrialization of the dry slag granulation process is presented, along with the various opportunities for valorization of the final product.

Chigwedu , Champion , HT-PEACS LLC , Germany

Abstract: Oxygen Steelmaking Reliable Production of Low Sulphur Steel Grades Without a Ladle Metallurgy Furnace The annual production of the Steelplant in question is 5 million metric tons of Flat Rolled Products. A significant percentage of the product mix requires final Sulphur levels of less than 50 ppm (0.0050 wt% [S]). When these steel Grades were scheduled, special steps were needed to minimize Downgrades and Cast Sequence Interruptions. The mandatory steps to be followed were: A -Desulphurize the incoming Hot Metal to 10ppm [S] or less B -Skim the “HECK” out of the Hot Metal transfer ladle, without regard to Yield losses C –Use only special low Sulphur scrap metal both at the BOF and at the Ladle Treatment Station as coolant D –Use special Low Sulphur Alloy Materials A careful study of the difference in chemistry between the final BOF-Slag and the required final LTS-Slag for a successful, final low Sulphur was carried out. In the end, new special steps, namely; E –Targeted control of the amount of BOF carryover slag F –Complete deoxydation of steel and carryover slag at BOF-Tap using Designed Deoxydation Cocktails G –Intensive and Efficient stirring at the LTS helped; -Reduce Hot metal skim losses, -Minimize Scrap metal cost -Optimize the use of expensive special low Sulphur alloy materials. Author; Dr.-Ing. Champion Chigwedu Technical Director of HT-PEACS LLC, USA. Tel.: +1 (703-350-7698) Email: cchigwedu@gmail.com cchigwedu@yahoo.com

Cho, Yongseok, POSCO, Korea, Republic of

Co-Author: Younhee Kang, POSCO

Abstract: The ZRM (Sendzmir Mill) is the cold rolling mill which consists of 20 rolls to produce the stainless steels and the electrical steels. The work roll of the ZRM is so small to reduce the thickness of the strip efficiently. At the beginning of the rolling, the roll force set-up was performed for the desired thickness of the strip. If the set value of the roll force is not correct for the outlet thickness, the thickness deviation is high, furthermore the strip is broken during rolling. For the ZRM process, sound prediction of the roll force is vital for achieving the desired thickness because the stability of the rolling substantially affected by it. In this paper, mathematical model is presented for the prediction of the roll force at the beginning of the rolling. The model consists of a numerical model for the prediction of the roll force, a sub-model for the prediction of the mechanical property of the strip by the deep learning, which is the deep neural networks. It is called numerical model based deep learning. From the combination of these models, the roll force at the beginning of the rolling can be predicted to produce the desired thickness of the strip. The numerical model based deep learning has several advantages compared with typical deep learning. The prediction accuracy has been improved from the physical tendency of the numerical model. In addition, from reduced number of inputs of the deep learning model, the learning time was decreased. The prediction accuracy of the proposed model is examined through comparison with actual data.

Choi, Hyoungkeun, Hyundai Steel Co. , Korea, Republic of

Co-Author: Kyunghwan Lim, Hyundai Steel Co.

Abstract: In the steelmaking process, the input of ferroalloy, especially Mn, causes a lot of heat loss. In this situation, the importance of the ladle furnace is gradually increasing as the production of high-grade steels containing a lot of alloys increases. However, due to the characteristics of LF operation, it is difficult to standardize operation, so automation is being developed later than other secondary refining facilities such as RH. However, with the recent development of machine learning techniques, it is possible to develop models with high accuracy, and it is also easy to connect the calculation results of these models with systems such as PLCs. As a result, demand for automation system development is increasing in LF as well. Our company developed a high-accuracy model for temperature prediction and completed a field test, and also developed a linear programming-based model for calculating the ferroalloy input. Based on the operator's operation performance, the pattern model according to the situation was configured as a rule-based system, and the automation system was developed by combining the previously developed temperature and ferroalloy model. As a result of applying an automated system that minimizes operator intervention to the operation, it was confirmed that more standardized and less variance operations were possible.

Chrzaszcz, Maéva, Hatch Ltd., Canada

Co-Author: Mitren Sukhram, Hatch Ltd. • Richard Elliott, Hatch Ltd. • Ian Cameron, Hatch Ltd. • Mariam Sidawi, Hatch Ltd.

Abstract: Nearly all Europeans steelmakers are considering a transition to direct reduced ironmaking and electric steelmaking – either in electric arc furnaces or electric smelting furnaces – as part of a decarbonization strategy. This paper discusses the application of biotechnologies to further reduce electric steelmaking emissions as steel companies aspire to achieve near-zero emissions. Fermentation of off-gas streams can convert carbon monoxide to a bioethanol by-product. Microalgae production is a candidate for carbon capture and sequestration to further treat these off-gases. Biochar can be used as a fossil-fuel alternative for reductants, carburizers, and/or energy sources. Biotechnologies as a pathway to near-zero emissions for electric steelmaking operations will be presented.

Cicutto, Simone, ergolines Lab s.r.l., Italy

Co-Author: Isabella Mazza, ergolines lab s.r.l. • Giovanni Schiavon, ergolines lab s.r.l. • Stefano Spagnul, ergolines lab s.r.l.

Abstract: Ergolines’ Ultrasonic Level Detector technology is an innovative technological solution for the contactless measurement of steel level in open stream casting. This technological solution is based on real-time measurement of the thermal profile in discrete points, based on the time of fly of ultrasonic waves in the copper tube. This technology, contrary to thermocouples and optical fibres, is contactless and, being installed on the water jacket, requires no machining of the copper tube. UT-LEVEL is the application of this innovative technology finalized to measure the copper temperature in the meniscus area, generally covering a length of 210mm. Based on the thermal profile data gathered, a dedicated algorithm extracts the steel level position, namely meniscus. Thanks to the fast response of the sensor and the high-performance electronic computation, the dynamic of the solution is aligned with the radiometric technology, utilized for the steel level control in most of the continuous casting machines worldwide. In detail, UT-LEVEL field of application is open stream casting process. An additional advantage of this solution is that the data of the thermal profile are visible in a dedicated HMI, and the rear data are available to the CCM for process optimization. Some systems of this not-radioactive technological solution for steel level control have already been installed and are currently operative.

Cicutto, Simone, ergolines Lab s.r.l., Italy

Co-Author: Isabella Mazza, ergolines lab s.r.l. • Giovanni Schiavon, ergolines lab s.r.l. • Stefano Spagnul, ergolines lab s.r.l.

Abstract: During the last years, the importance of powder feeding has become more and more central for the optimization of the continuous casting process with submerged stream. A first technological step ahead has been the introduction of the powder feeder enabling to keep constant the addition of lubricating powder and keep homogenous its distribution. A huge added value is given by the powder thickness control in close loop. This is possible thanks to the integration in the system of a dedicated sensor which operates by comparison with the main sensor for steel level control. The advantages of this solution are several, as keeping constant the thickness of lubricating powder, reducing the steel level fluctuation, reducing break-outs risks, reducing powder entrapments into liquid steel. The solutions for the powder thickness control here reported are classifiable in two families: sensors to be installed on the casting floor (as for example laser triangulation) and sensors installed in the mould assembly (as UT-POWDER installed in the water jacket/backplate). The sensor for powder thickness control installed on the casting floor presents the advantage that one sensor is common for more casting sizes, but there are limitations due to geometrical dimensions, to steel level sensor characteristics, and also to the operativity, being installed on the casting floor. The UT-POWDER, ergolines solution installed in the mould assembly, presents several advantages such as non-interference on the operativity of personnel on the casting floor, a wider application range, and the possibility to gather some additional information as thermal profile in the meniscus area.

Claußnitzer, Robert, AKW Apparate + Verfahren GmbH, Germany

Abstract: Almost all the iron and steel manufactured in the world is made from pig iron produced by the blast furnace process (BF). However, the dust and especially the sludge generated during the process, do constitute a great challenge for the improvement of the overall sustainability of this highly material and energy intensive industry. During the production of pig iron in blast furnace, a Zn- and Pb-containing sludge is generated in the exhaust air cleaning system. More than 50 % of the mass input becomes outputs in form of off-gas and solid wastes/by-products. This toxic waste can be landfilled after dewatering and pretreatment, which is very costly. The sludge particles contain large amounts of Fe and C that could be recycled in the furnace. However, the Zn content of the sludge is high, and the Zn input to the blast furnace must be limited. There are no standard processing concepts for a BF-sludge treatment plant. The process design and plant arrangement will primarily depend on the nature of the feed sludge and therefore will be based on analysis and pilot test work that is being performed in AKW Equipment + Process Design technical laboratory. On basis of the test results, the suitable and customized process solution will be developed, discussed and later on engineered and executed by AKW Equipment + Process Design. This unique process concept is presented in the following paper: multi-stages hydrocycloning, combined with thickening and filter pressing. Key Words Blast Furnace Sludge, Zn-reduction, Hydrocyclones, Thickeners, Filter Press,

Cojocaru, Vasile Danut, University Politehnica of Bucharest, Romania

Co-Author: Elisabeta Mirela Cojocaru, University Politehnica of Bucharest • Nicoleta Zarnescu-Ivan, University Politehnica of Bucharest • Nicolae Serban, University Politehnica of Bucharest • Mariana Lucia Angelescu, University Politehnica of Bucharest

Abstract: The influence of solution treatment duration on the microstructure and mechanical properties of a hot-rolled UNS S32750 / F53 / 1.4410 Super Duplex Stainless Steel (SDSS) alloy was investigated in this study. The UNS S32750 / F53 / 1.4410 SDSS alloy was thermomechanical (TM) processed by hot-rolling deformation at a temperature of 1100°C with a total deformation degree (total applied thickness reduction) of 70%, followed by a solution treatment. The solution treatment was performed at temperatures between 1080°C to 1180°C, in 20°C increments, with a fix treatment duration of 20min. The microstructure evolution during TM processing was investigated by XRD and SEM-EBSD techniques, while the mechanical properties by tensile and impact testing techniques. The following microstructural characteristics were analysed: constituent phases, weight fraction, grain-size and phase morphology. The mechanical behaviour was assessed through the following properties: absorbed energy, ultimate tensile strength, yield strength and, elongation to fracture. The performed solution treatments induced significant changes in relation to alloy's microstructure and showed a direct influence on the exhibited mechanical behaviour.

Conrads, Hans Georg, PROMECON process measurement control GmbH, Germany

Abstract: An often-neglected process step in electric steelmaking is the monitoring of the off-gases from the electric arc furnace, although such monitoring brings enormous potential for process optimization. Precise knowledge of the gas flow and the CO2/CO ratio enables plant operators to control the melting process sustainably and efficiently. PROMECON developed a non-extractive, real-time, and drift-free measurement method that makes exhaust gas analysis at the electric arc furnace easy. The digital measuring system determines the measured values in real time and thus enables very short reaction times for process control. The consequences are high savings in energy, fewer faulty batches, and higher steel quality. Learn how you too can drastically reduce the power consumption of your melting process.

Cosentino, Pietro, ArcelorMittal, France

Co-Author: Sami-Alex Zaïmi, ArcelorMittal

Abstract: Controlling the charging of the blast furnace is essential to ensure the burden distribution needed for a stable operation, high performance, low coke consumption and low CO2 emissions. The goal of this work is to study the impact of the chute geometry on the stream of particles. DEM has been chosen as the mathematical approach for simulating the granular flow. A series of simulations has been performed with modified geometries to study their impact on the stream of particles. To quantify that impact, the main aspects monitored were the thickness and the speed of the stream at the tip of the chute. The results showed the importance of simulating the proper geometry of the chute, as minor geometrical changes can have a big impact on the results. That approach brings perspectives on how to improve the geometry of the chute and on how it can influence the burden distribution in the furnace.

Costa, Afranio, Gerdau Acominas S.A. , Brazil

Co-Author: Andre Nascimento, Gerdau Acominas S.A. • Gilberson Storck, Gerdau Acominas S.A. • Jose Maria Ibabe, Asseco CEIT a.s. • Gabrielly Oliveira, Universidade Federal de Minas Gerais • Antonio Gorni, Companhia Brasileira de Metalurgia e Mineração • Alisson Oliveira, NSigma Consulting • Gilberson Melo, Gerdau Acominas S.A.

Abstract: Macro and microsegregation play an important role in understanding the solidification behavior of continuously cast steels. Both affects directly critical applications, which requires a higher degree of homogeneity since as cast stage. This study applied macro and micro approaches to perform a comprehensive characterization of the solidification microstructure of a slab with U-shape centerline segregation. In the macro-approach, a width-wise chemical analysis was performed using OES-PDA on whole centerline. Thickness-wise analysis was also implemented at 300 mm intervals in width direction. Carbon content in centerline was almost 3 times higher than at a point 37.5 mm below the surface. The same behavior happenned with P, S, Ti and Nb. The micro-approach in this study considered SDAS (Secondary Dendrite Arm Spacing) and second phase particles. Calculated figures presented very good correspondence with measured ones for both micro-approach features. Mushy zone was calculated using CON1D model and phase fraction was calculated both by CON1D and FactSage 8.2. NbC, TiN and MnS were the most relevant second phase particles calculated by Factsage. This finding matches to the analysis carried out by SEM-EDS. Based on these results, which measured values were in good agreement with calculated ones, it is possible to estimate the internal quality of slabs in a higher degree of confidence.

Costa Braga, Barbara, Vallourec, United States

Co-Author: Aurelien Fabas, Vallourec • Charles Delvaux, Vallourec • Michael Kan, Vallourec • Andre Assis, Vallourec

Abstract: Steel cleanliness has become increasingly important throughout the years, bringing steelmaker’s attention to operational parameters that can optimize and fulfill these quality requirements. Argon stirring at the LMF is one of the key steps on achieving optimized steel cleanliness, especially if rinsing is performed before CaSi addition (pre-rinse). Trials were performed at Vallourec Star (Youngstown-Ohio) and heats were produced in 2 different scenarios: with and without pre-rinse. Lollipop samples analyzed on ASPEX demonstrates that pre-rinsed heats presented a strong drop on inclusion density (by -50%) when compared to heats that were not pre-rinsed (inclusion density stable). Pre-rinse practice was standardized at VStar.

Cremer, Michael, thyssenkrupp Steel Europe AG, Germany

Abstract: Coke plant Schwelgern, commissioned in March 2003, is still running the biggest coke ovens worldwide with a coke output of more than 56 tons per oven. The so-called Coke Stabilizing Quenching, the state of the art regarding wet quenching processes, realizes the procedure of coke quenching. The two quenching towers are the highest industrial wood constructions worldwide and are hardly stressed by the coke quenching process itself. After more than 20 years and more than 50 million tons of produced coke, the quenching towers have reached the end of their life cycle. This presentation shows the dismantling and assembly of the southern quenching tower during ongoing coke plant operation.

Cruz, Daniel, TMT GmbH, Germany

Co-Author: Volker Langer, TMT Tapping Measuring Technoloy GmbH • Claude Meisch, TMT Tapping Measuring Technology S.a.r.l

Abstract: Casthouse and Digitalization appear to exclude each other at first sight. Especially considering application of Blast and Metallurgical Furnaces. Since more than 100 years they are acme of heavy industry, hard work and challenging environmental conditions. But how does digital evolution fit into it? It is driven on the requirements of better safety, reproducibility, predictability and documentation. Since more than 20 years, TMT Tapping Measuring Technology in Luxembourg and Siegen has developed with its customers and partners solutions for • Automation, • Visualization, • Data Management and • Virtualization, in order to meet above expectations. The usability for the user are remote commissioning, virtual training, asset performance management and significant stability and efficiency on the tapping process.

Daghagheleh, Oday, Montanuniversität Leoben , Austria

Co-Author: Johannes Schenk, Montanuniversität Leoben, K1-Met GmbH • Michael Zarl, K1-MET GmbH • Heng Zheng, Montanuniversität Leoben • Manuel Farkas, K1-MET GmbH

Abstract: Alternatives to fossil fuels are worth developing to shift to carbon-free iron making. Accordingly, replacing coal, coke and natural gas with H2 is the current trend. H2 is mainly produced through steam reforming and partial oxidation, which are not carbon neutral. A promising method to produce H2 is the decomposition or pyrolysis of natural gas using plasma technology. If the required energy for pyrolysis is provided from a renewable source, the CO2 footprint can be further minimized. Using thermal plasma pyrolysis in combination with hydrogen-based iron making in a fluidized bed can lead to an enormous decrease in CO2 emission. Thermal plasma converts electrical power to thermochemical energy and offers temperatures up to 10000 k. This temperature range requires no catalytic effect for the decomposition reaction to occur. The other advantages of plasma are the relatively small and simple technology, high-efficiency rate, low energy demands, and high grades of Carbon Black (CB) products besides the enriched H2 gas. CB, as a worthful byproduct, can be forwarded for applications in, e.g., the mobility, plastic, or agriculture industries. The methane pyrolysis is tested on a laboratory scale using a DC-transferred plasma arc system with a maximum power of 8 kW, providing a voltage range of 20-100 V and a maximum current of 150 A. The arc is initiated between a hollow graphite cathode and the graphite pin anode. The plasma gas (2l/min Ar) and methane (1-1.5 l/min CH4) are introduced to the reaction zone through the cathode. The off-gas could flow out for further analysis, and the arc could be seen through the openings at the top. The results show a CH4 conversion rate of 50 to 95 % depending on the testing parameters. The produced carbon black is fluffy and fine with high purity. Its structure can be amorphous or turbo.

Dahmen, Burkhard, Chief Executive Officer, Chairman of the Managing Board, SMS group, Germany

Abstract: The metals industry is facing a historical transformation. Around 10 percent of global CO2 emissions are generated in the production of steel, aluminum and copper. Since humankind will need more steel and metals in the future, one thing is obvious: without the sustainable production of metals, we will not be able to save the climate. However, there is good news. The technologies and solutions for "turning metals green" are ready. As SMS group, we don't just see ourselves as pioneers in this. We are already showing that it works. With H2 Green Steel, the world's first climate-neutral steel mill is currently being built in Sweden, for which the SMS group is supplying the entire process equipment. The direct reduction plant will be the first commercial facility in the world operating 100 percent with hydrogen. This project demonstrates that the future of steel production is possible on an industrial scale. But in addition to greenfield projects, there are also solutions for existing steel mills. By injecting hydrogen or hot synthesis gases, we can reduce the carbon footprint of an existing blast furnace by around 30 percent. Our metallurgists are currently working on a new furnace with a CO2 reduction potential of up to 70 percent - a milestone on the way to decarbonizing existing steel mills. Recycling also plays a central role in this. Returning recyclable materials to the product cycle is the most efficient way of avoiding CO2. Electronic scrap, motherboards, cell phones - there is enormous potential here. And last but not least the possibilities of digitalization: digital tools and methods such as predictive analytics expand the service for our customers and enable us to significantly reduce the energy consumption of an entire plant. Concluding: The path to climate-neutral metal production is challenging, but it is right in front of us.

Del Gobbo, Matthew, Hatch Ltd. , Canada

Co-Author: Tom Plikas, Hatch Ltd. • Claire Velikonya, McMaster University • Jayant Borana, CRB Canada • Iakov Gordon, Hatch Ltd. • Umesh Shah, Hatch Ltd. • Matthew Del Gobbo, Hatch Ltd.

Abstract: This paper describes the use of first principles-based approaches to predict the performance of existing and developing assets in the ironmaking flowsheet such as, for example, indurating/pelletizing machines and sinter coolers where the interaction between the solids, gas, and heat flows occurs in a recycled, coupled manner. Quantifying this interaction empirically or through field trials can be challenging. Examples are provided where physics-based models have been developed to simulate the operation of an existing unit and have been validated against field data to ensure they are representative of real-world performance. These approaches are useful for assessing how an existing and developing piece of equipment would respond to a proposed change in the process and operation. These changes can include, for example: re-configuring machine and energy flows for increased solids throughput and/or final pellet quality, reducing fuel consumption per ton of production to improve energy efficiency and reduce carbon-footprint, evaluating the impact of alternative feed type on machine performance, identifying and minimizing air ingress or air leakages, evaluating the feasibility of alternative energy sources such as resistive heating, plasma torches or biomass on performance, and improving overall process control strategies. Outputs from such models include mass and energy balances, solid and gas temperature profiles along the bed height and machine length, extent of heterogeneous reactions in the solids (drying, magnetite oxidation, etc.), interzonal gas flow movements, gas pressure drop prediction and impact on mechanical equipment requirements, refractory & furnace temperatures, burner/combustion performance, air ingress/leakage rates, and other technical parameters associated with machine performance affected by the gas dynamics and solids energy flows. These models are particularly useful as a database generator to improve real-time process control of the equipment.

Della Rocca, Alessandro, Tenova S.p.A., Italy

Co-Author: Claudio Leoncini, Tenova S.p.A.

Abstract: The European Green Deal, the Paris Cop21 agreement and the ‘Fit for 55’ climate package all set ambitious targets in terms of greenhouse gas emissions reduction. Consequently, European iron and steel producers need a paradigm shift to fulfill environmental regulations and to carefully evolve their processes towards low-carbon footprint technologies without losing competitiveness or profitability. To this end, both steel production stages, Upstream (up to liquid steel) and Downstream (from liquid to solid steel), need to implement an evolution or replacement of current technologies. Reduction of iron ores remains the most carbon intensive process and several technologies are currently under scrutiny for minimizing its carbon footprint. Anyway, more than 40% of European steel comes from scrap recycling with direct carbon emission intensity of about 130 kgCO2e/ton for the Upstream portion. In this case, reheating and heat treatment processes in Downstream, accounting for 50-190 kgCO2e/ton depending upon the product type, cover a relevant fraction of total direct carbon footprint of steel products. Consequently, the decarbonization of electric steel production must also take into account hot rolling and heat treatment processes. In this energy transition scenario, Tenova proposes a stepwise solution to the decarbonization of heating furnaces. After a first step of thermal efficiency optimization of existing equipment, electrification is pursued as far as possible to maximize energy efficiency. This is possible only up to a critical temperature, where other process constraints (scale formation, heating efficiency, production flexibility) come into play. Hydrogen and non-fossil fuels combustion are required for the final temperature increase, while also providing a protective atmosphere against surface oxidation. The sequence of implementation of these energy transition steps follows the availability of resources as foreseen in the energy transition scenario for Europe, thus providing to steelmakers a low-risk implementation of steel production decarbonization.

Dr. Denecke-Arnold, Heike, Chair of the Conference, Chief Operations Officer, thyssenkrupp Steel Europe AG, Germany

Co-Author: Arnd Köfler, Chief Technology Officer, thyssenkrupp Steel Europe AG

Abstract: Each integrated steel mill and its production portfolio is unique – and therefore, each mill must find its individual way to decarbonize. At thyssenkrupp Steel Europe, we defined our path towards a green and sustainable future through a new and innovative DR-SAF-BOF steel route. For a successful transformation, we are taking bold action and aim to produce 5 Mt of low-CO2 bluemint® steel by 2030. This keynote outlines our decarbonization strategy and how it supports our customers in their decarbonization.

Dr. Denecke-Arnold, Heike, Chair of the Conference, Chief Operations Officer, thyssenkrupp Steel Europe AG, Germany

Abstract: Opening of METEC & 6th ESTAD 2023

Dengler, Christian, Paul Wurth S.A., Luxembourg

Co-Author: Olivier Mersch , Paul Wurth S.A. • Volodymyr Kuskov, Paul Wurth S.A. • Dirk Malcharek, Paul Wurth S.A. • Fabrice Hansen, Paul Wurth S.A.

Abstract: Following the old proverb that you cannot manage what you cannot measure, tracking of important production metrics is a requirement for staying competitive in the global market for iron and steel. The digital transformation promises new insights for production improvements through, among others, an increase in advanced data analytics, newer and smarter sensors and an improved exchange and display of information. Leveraging such potential through the realization of value adding digital solutions poses its own challenges for many plant operators in the iron and steel sector, foremost the lack of available work force with the required qualifications and the development time and costs for such software. For technology suppliers, this implies developing and delivering tools that provide immediate benefit and sufficient flexibility to integrate new diagnostics for specific problems or plants. Paul Wurth is continuously improving and developing such tools. Recent developments of such tools and their added value for ironmaking are topics of this article. In the article, we present how we reduce the time to product for condition monitoring and process optimization solutions using our low-code development platform DataXpert and show the general approach for the development of such systems using this platform. We then provide tangible examples of existing template solutions in ironmaking that are developed using this platform. Those template solutions deliver a set of existing functionalities and can be adapted or extended to the needs and requirements of specific plants. Added value is illustrated on several examples: monitoring of high level metrics for slag granulation, diagnostic analytics for coke machines or predictive maintenance for the bell less top.

Dias, Rodrigo Madrona, Usiminas S. A., Brazil

Co-Author: Fabiano Moreira, Vesuvius • Saku Kaukonen, SAPOtech Oy • Rodrigo Seara, Usiminas S.A. • Rodrigo Madrona, Usiminas S.A. • Maria Maria Carolina Campos, Vesuvius • Márcia Maria da Silva Monteiro Pereira, Vesuvius • Hannu Suopajärvi, SAPOtech Oy • Fernando Quinelato, Vesuvius • Gabriel Ribeiro, Vesuvius • Joilson Moreira, Vesuvius • Moises Miranda, Vesuvius • Vasco Esteves, Vesuvius • Hervé Tavernier, Vesuvius • Maxwell Rogana , Vesuvius

Abstract: One of the most important functions of mold fluxes is to maintain and improve semi-product (slab, bloom, billet) surface quality through a continuous lubrication, and a controlled heat transfer between the solidifying steel shell and the mold. Typically, the evaluation of the mold flux performance and impact on the semi-product surface quality is conducted manually by a skilled professional. There are many drawbacks with this current approach. Manually conducted visual inspection takes a lot of time, there is a long delay as the surface cannot be inspected until the semi-product has cooled down, and the documentation of the findings is many times insufficient. In some cases, it is not even possible to inspect the surface if the semi-product is directly forwarded to a conditioning step (scarfing/grinding) or to a hot rolling mill. To overcome the inefficiencies described above, this paper presents an approach where automatic surface inspection system is used to evaluate the slab surface quality and the performance of mold fluxes. It is shown that the system can be easily and effectively used to evaluate casting fluxes behavior on both peritectic and ultra-low carbon steel grades, allowing to reduce operational and quality risks and to go faster in the qualification of new and improved mold fluxes

Diegelmann, Volker, VDEh-Betriebsforschungsinstitut GmbH, Germany

Co-Author: Roman Kuziak, Łukasiewicz Research Network – Upper Silesian Institute of Technology • Andrij Milenin, AGH University of Science and Technology • Szczepan Witek, AGH University of Science and Technology • Maciej Pietrzyk, AGH University of Science and Technology • Krzysztof Bzowski, AGH University of Science and Technology • Łukasz Rauch, AGH University of Science and Technology • Christian Trappmann , MANNSTAEDT GMBH • Andreas Falck, MANNSTAEDT GMBH • Nora Egido Perez, Sidenor Investigación y Desarrollo • Victor Manuel Santisteban Mendive, Sidenor Investigación y Desarrollo • Hagen Krambeer, VDEh-Betriebsforschungsinstitut GmbH • Monika Feldges, VDEh-Betriebsforschungsinstitut GmbH • Nils Hallmanns, VDEh-Betriebsforschungsinstitut GmbH

Abstract: During rolling, straightening and thermal processes internal stresses arise impairing the products material properties and causing material distortion due to stress relief mechanisms. The characteristics of those effects are still associated with a high degree of uncertainty. To overcome these uncertainties, an improved and highly advanced process technology is required combining hybrid process models (physical and statistical) with a virtual plant model (digital twin) that enables online simulation of material conditions and properties, e.g. residual stresses responsible for deformations, by use of soft sensors. The locally varying degrees of deformation and temperature profiles during production lead to problems regarding shape stability, straightness and level of residual stresses. To predict the effect of the different processing steps on the quality of the products more accurately, online capable residual stress determining techniques are mandatory to control processes from a perspective of internal stresses as the main influencing factor for shape and straightness. A hybrid approach is chosen combining material, physical and data-based process models to a soft-sensor for residual stresses. It comprises experimental material, analytical and statistical process data to generate knowledge for the realization of a “residual-stress-based” process strategy. A product related container gathers all relevant data and serves as a repository for relevant models to calculate non-measurable data. The data and model container is realized today by the digital twin technology. As a direct online measurement of residual stresses is not possible, the development of a soft-sensor for residual stresses will solve this technological gap and can be used for further process control.

Diekmann, Uwe, Matplus GmbH, Germany

Co-Author: Petra Becker, Matplus GmbH • Dominik Zuegner, voestalpine Forschungsservicegesellschaft Donawitz GmbH • Sabine Zamberger, voestalpine Forschungsservicegesellschaft Donawitz GmbH

Abstract: A key challenge for steel manufacturers and users is the rapid creation and use of new technologies with improved environmental performance as a product of lightweighting and circularity. The acceleration of development processes can be achieved through the use of modern simulation techniques that also draw on extended knowledge bases. One element of the extended knowledge base is VDEh's Stahldat SX. Beyond standard data the Stahldat SX knowledge base includes research reports of applied steel research (FOSTA) and a growing number of models for transformation kinetics (TTT, Jominy), plasticity (flow curves) and compliance information (CAS-numbers). In practical application the information is extended by own results from material qualification projects along the process chain as well as specific CAE interfaces. For green steel technologies the mass- and energy flows as time series data along the process chain are subject of evaluations. Practical results with regard to accelerated development of new steel technologies are presented. This includes the consideration of energy demands along the process chain and comparisons to LCA data.

Dimmer, Martin, Celsa Steel UK, United Kingdom

Abstract: Celsa group and Celsa UK are a recognized leader in scrap recycling and in sustainability. The scrap recycling paves the way to EAF slag-making process challenges due to scrap quality volatility in general and to Al2O3 slag content management in particular. Together Celsa UK and Lhoist implemented a cost-efficient slag making process managing the inconvenience of High and variable Al2O3 content of the EAF slag. The key lever was introducing dolime as a MgO source input to control and regulate the slag viscosity. Based on theoretical approach and calculations, a Al2O3 and MgO management of the EAF slag-making process was defined. This process was implemented and tested industrially at Celsa UK bringing positive impacts on material recovery, refractory wear, energy yield, CO2 emission intensity in particular. This paper will describe the theoretical approach and calculations as well as will present and discuss the industrial results of the new EAF slag-making management at Celsa UK leading to a more sustainable and cost efficient EAF process.

Dornelas, Bárbara, CRM Group, Belgium

Co-Author: Clément Polato, ArcelorMittal R&D France • Maria Pacheco, Tata Steel Ltd • Laurent Fraiking, CRM Group • Clément Polato, ArcelorMittal R&D France • Maria Pacheco, Tata Steel Ltd • Laurent Fraiking, CRM Group

Abstract: The dependency to raw materials costs makes the management of sintering plants an everyday challenge to reach the requested sinter quality and production rates while meeting all the environmental constrains (CO2 but also other pollutants like NOx and SOx). The increase of by-products recyclability and recycling rate shall improve both raw materials costs and environmental issues, improving competitiveness and sustainability of European steel industry with limited impact on process KPI’s. SinByOSe RFCS funded project focuses on selective preparation of by-products and solid fuels. The selective preparation of part of the sinter mix is a local countermeasure by means of chemical upgrading (removal of detrimental elements by pre-processing) and by means of particle shaping (pre-granulation). Main solutions investigated in the SinByOSe project consist in : • An innovative pre-processing to increase sinter dust recyclability doing a closed loop washing. The Chlorine abatement obtained is close to 91% and a high %KCl solution is generated, which could be valorized. • Selective pre-granulation of a selected part or whole of the by-products to be recycled through the sinter plant. Current results allows up to 16% productivity increase. • Solid fuel pre-granulation with lime, by intensive mixing, for process and environmental improvement. Results showed an increase of productivity up to 3 tsinter/m².d, a gain of solid fuel of 1 kg/tsinter and constant sinter quality. Environmental results showed a reduction by 15% of SO2 and dust emissions.

Dratner, Christof, cunova GmbH, Germany

Co-Author: Hebel Rudolf, FKM Engineering • Jürgen Hochhaus, AG der Dillinger Hüttenwerke • Jörg Hunger, ArcelorMittal Eisenhüttenstadt

Abstract: Significant campaign life extensions of the Blast Furnace (BF) of more than 15 years are the customers demand all over the world. The required target life can be reached by the well established classical copper cooling stave, covering the BF-shell from the hearth up to parts of the BF-stack. Some BF-areas, like bosh and belly (cohesive zone) as well as the transition zone (lower and middle stack) are critical wear attack mechanism zones. In these critical BF-areas, the copper cooling staves, covered with conventional wear protection linings have shown that they are not sufficient enough to reach the customers demand. During the long-lasting BF-campaign, especially in the cohesive zone, like bosh, belly and lower stack; natural accretion layers may form in front of the copper cooling staves by freezing a mixture of slag and pig iron. Unfortunately, all of the formed accretion layers are not stable enough to protect the copper stave surface in case of rough wear mechanisms, like descending burden and upstreaming gasjets during the BF-campaign. Copper stave wear protection linings, such as metal- or cast iron inserts, refractory mass / mixes- top coatings, shotcastings/shotcretings, solgel refractory mass; as well as all kind of graphite-, doped carbon-, high alumina- or silicon carbide refractory bricks are not abrasion resistant enough to protect the copper cooling stave surface during the long-lasting BF-campaign, to reach the required life time target. This presentation is focusing on: • The proven copper cooling stave concept, design and realisation; especially for the bosh and the stack transition zone. • The developed, well experienced and installed copper cooling stave wear protection; using very high abrasion resistant silicon-infiltrated and reaction-bonded silicon carbide (RBSiC)-Inserts.

Duan, Shengchao, Hanyang University, Korea, Republic of

Co-Author: Taesung Kim, Hyundai Steel Co. • Jinhyung Cho, Hyundai Steel Co. • Joohyun Park, Hanyang University

Abstract: The effect of slag composition on the refining and reoxidation behavior of Si-killed 316L stainless steel during ladle and tundish processes were investigated in an induction furnace equipped with a MgO crucible under high purity Ar atmosphere at 1873 K and 1773 K, respectively. For the ladle refining process, the total oxygen (T.O.) content decreased with increasing the Vee ratio (CaO/SiO2=C/S, 1.0, 1.3, 1.7, and 2.3) of the CaO-SiO2-Al2O3-MgO-CaF2 ladle refining slag, but the effect of CaF2 content (15, 20, 25, and 30 %) on the T.O. can be neglected at high C/S condition. The CaO-SiO2-Al2O3-MgO system liquid inclusions can be found as the C/S < 1.3, while the formation of spinel and MgO inclusions were observed at the C/S > 1.7 for a fixed CaF2 content (10 %). For the tundish metallurgy process, the liquid and SiO2-rich Mn-Si-O system inclusions were found as the liquid steel reacted with rice husk ash (RHA) and RHA-CaO-SiO2. The liquid Mn-Si-Al-O system inclusions were observed as reacted with RHA-CaO-Al2O3 flux. The number density of inclusions increased, decreased, and remained constant with the reaction time when the liquid steel reacted with RHA, RHA-CaO-Al2O3, and RHA-CaO-SiO2 fluxes, respectively. The results indicated that the reoxidation of the liquid steel is aggravated as the RHA was used, whereas the RHA-CaO-Al2O3 can facilitate the removal of the inclusions during the tundish metallurgy process.

Duddek, Mike, Ruhr West University of Applied Sciences, Germany

Co-Author: Saulo H. Freitas Seabra da Rocha, Ruhr West University of Applied Sciences

Abstract: Electrical scrap, particularly battery-powered tools, contain in most cases alloyed steels. These materials are usually incorporated into devices with many other materials, such as copper, aluminium, or magnetic components, making recycling difficult. In traditional recycling approaches, devices are usually shredded as a whole, and the resulting fine fraction is separated in various process steps. This usually generates mixed-metal scrap, as a wide variety of metals are blended. Because of the shredding process, various materials are mechanically bonded (interlocking), making separation difficult, in particular, the separation of softer metals such as copper and aluminium from harder metals such as steel. With a robotised targeted destructive separation of the electrical devices prior to mechanical shredding, this problem can be avoided, and an alloyed steel fraction can be obtained. Using the example of a cordless screwdriver, the separation of the chuck and gearbox from the rest of the device results in a fraction containing only alloyed steel and plastics, without added copper, aluminium or magnetic components, that can be recycled directly in an electric arc furnace. Such targeted destructive fractionation can increase the value of the material stream of electrical scrap and simplify the recovery of high-quality recycled materials. The process of such robotised targeted destructive fractionation and the achieved material qualities are presented in this paper.

Dumortier, François, John Cockerill, Belgium

Abstract: Climate change is the biggest threat that humankind has ever faced. The decarbonization of transport is a crucial part of the solution to reducing greenhouse gas emissions and global warming. One of the most notable trends in this field is the considerable growth of the electrical vehicle market that is forecasted to become exponential in the coming years. Consequently, the production capacity of non-grain-oriented (NGO) electrical steel will have to increase at the same pace in order to fulfill the drastically and rapidly growing market needs. While addressing this challenge, electrical steel producers will also have to find ways to produce thinner strip and increase its silicon content to make vehicles lighter and considerably improve the efficiency of electric motors. To address the extremely difficult rolling of this type of advanced electrical steels, John Cockerill has developed a new 6-Hi reversing mill called: E-Qual® Mill. Its innovative design features an optimized work roll diameter specifically designed to avoid the roll flattening of thinner gauge electrical steel strip, all while providing the torque requirements for the first passes. Since this type of electrical steel is very brittle at ambient temperature, the E-Qual® Mill’s new design foresees the installation of an inductive heater on the pay-off reel pass line to avoid strip breakage at the first pass. Additionally, its upgraded cooling system allows for the highest degree of thickness homogeneity required to produce highly-performant electrical motors. The technical paper will present the new multi-functional mill design and the main technical characteristics of the mill.

Dwyer, Claire, Tata Steel Ltd , Netherlands

Co-Author: Manuel Atienzo, Tata Steel Ltd • Robert-Jan Pielkenrood, Tata Steel Ltd • Aart Overbosch, Tata Steel Ltd • Huijuan Ding, Tata Steel Ltd

Abstract: The injection of gas through the porous plugs during ladle treatment is important for the homogenisation of both steel chemistry and temperature and is critical to ensure the production of high quality steel. It is important to monitor the stirring performance as it is difficult to visually observe by the operators, even with the help of the surveillance camera and there can be leakages in the system or blockages of the porous plugs that affect the operation. To be able to objectively assess the stirring of a ladle during treatment at Ladle Furnace 22, in the steel plant of Tata Steel IJmuiden, a uniaxial accelerometer was installed on the ladle transfer car. This data was then processed and wirelessly transmitted on a per second basis to both the production PLC and a historical storage server. This data was then modelled and the output was shown to the operators on a screen in the pulpit. There were many learnings throughout the implementation process. This paper will elaborate the experiences during the project and what was achieved. After a period of preparation, a setup was installed and commissioned successfully. Since implementation all ladles are objectively rated and with this proof of concept complete it can be rolled out to the second plug of the ladle and then to all the other ladle treatment stations.

Ece, Ömer, İskenderun Iron and Steel Co., Turkey

Co-Author: Erman Kaya, İskenderun Iron and Steel Co.

Abstract: The main task of coke factories in Iskenderun Iron and Steel Co. (ISDEMIR) is to produce metallurgical coke needed by blast furnaces. The final stage of coke production is completed with the quenching processes. In ISDEMIR, it is used two types of methods which are dry and wet quenching in the coke plant. In this research, it is shown how the same coke battery oven, same blend and the same conditions effects the coke quality parameters, such as moisture, coke reactivity index, coke strength after reaction and blast furnace production process by wet and dry quenching methods.

Eisbacher-Lubensky, Jan, Montanuniversität Leoben , Austria

Co-Author: Christina Brus, voestalpine Stahl Donawitz GmbH • Stefan Wegscheider, voestalpine Stahl Donawitz GmbH • Christian Weiß, Montanuniversität Leoben

Abstract: In the sintering of iron ores, the chemical composition and the physical properties of coke breeze has a significant effect on the sinter process and the sinter quality. This paper is focused on the influence of coke breeze from different deposits and coking plants respectively, on the sinter process in particular on the off gas composition and the sinter quality. Laboratory-scale sinter feed mixtures with various sorts of coke breeze are produced, whereby the particle size distribution of the investigated coke breeze is constant as well as the coke breeze content with respect to the fixed carbon content. The small scale sinter experiments are performed in cylindrical packings of sinter mix. During the sintering the emissions of CO, CO2, NOx and SO2 in the off gas are monitored, as well as specific sintering parameters e.g. the sinter yield and strength. The results of the off-gas analysis are compared with the chemical elemental analysis of the coke breeze. The investigations demonstrate that a high carbon content of the coke breeze leads to a higher pressure loss across the sinter bed, thus to a shorter sintering time and correspondingly to higher productivity. Changes in the nitrogen concentration in the coke breeze cause significant NOx variations in the off gas. As expected, the total sulfur in the off gas cannot be entirely attributed to the coke breeze. The findings obtained on a laboratory scale enable a coke breeze characterization close to an industrial sinter belt, demonstrating the expected process parameters.

Elixmann, Sina-Maria, RWTH Aachen University, Germany

Co-Author: Dieter Senk, RWTH Aachen University • Markus Schäperkötter, Salzgitter Flachstahl GmbH • Peter Müller, Salzgitter Flachstahl GmbH

Abstract: Surface quality of semi-finished products is mainly formed in the mold. Thus, the quality of the slab can be well adjusted by the correct setup of the mold. To be able to analyze the dynamics of solidification of the strand in the mold during the process, fiber optics were implemented in the mold plates of the narrow and broad faces. In total 476 measuring points provide a good monitoring of the temperature field of all four faces of the mold. Measurements were carried out using the new fiber optic measurement technology. Local heat fluxes can be determined from temperature measurements, if the geometrical und physical properties of the heat transfer layers in the mold region are known. During the use of measurement technology, process parameters were varied, which lead to a different development of the temperature field. Thus, based on the temperature data, it can be estimated which deformation of the strand shell happen in the mold during casting. At the end, the significance and transferability of measured cold and hot spots in the copper plate for the strand shell is discussed.

Elliott, Richard, Hatch Ltd. , Canada

Co-Author: Ian Cameron, Hatch Ltd. • Gino De Villa, Hatch Ltd. • Jeff Eastick, Hatch Ltd. • Julia Allard, Hatch Ltd.

Abstract: Shaft furnace direct reduction technology has proliferated globally over the past half century and more than 100 modules are currently operating. Choosing where to build these furnaces has been generally straightforward: build where natural gas is inexpensive and abundant. The next generation of direct reduction modules faces a more complex choice. Net zero scenarios for the iron and steel industry call for doubling the number of installed modules in half the time it took to deploy the existing fleet. Many of these new facilities will eventually use hydrogen as a reductant and must consider how their location affects their ability to transition partially or completely to hydrogen, electrify heating, access a competitive global iron ore market, and respond to accelerating legislated and voluntary decarbonization drivers. A transition to hydrogen-based ironmaking also forces a discussion on where to produce the required green hydrogen. Producing the hydrogen locally requires abundant green energy and freshwater; transportation from other regions, by pipeline or liquid ammonia conversion, may struggle to economically supply the immense volumes of hydrogen required for ironmaking. So, if the goal is decarbonization of the steel industry, why not move iron instead? DRI is already an effective means of ‘virtually’ exporting natural gas, enabling movement of solid iron rather than liquified gas, and can serve a similar export function in a future hydrogen economy. This paper aims to provide guidance for assessing the complex and competing factors affecting the choice of location for the next generation of direct reduction modules. These factors will be analyzed on a global basis and used to highlight the most promising regions for producing natural gas-based DRI while enabling a transition to hydrogen-based ironmaking. This paper will also compare technical and economic aspects concerning the export of hydrogen-based DRI with the export of hydrogen energy carriers.

Eom, June yong, Hyundai Steel Co. , Korea, Republic of

Abstract: As we already know, the Carbon Neutrality is the most essential global issue since 2010s. Many heavy industries, especially Iron & Steel producing industries, are being forcing to achieve extremely low emissions of carbon dioxide. There are lots of studies for the carbon neutrality of the steel making process, but the process transition from BF-BOF to DRI-EAF is considered to be one of the most certain methods. DRI makes it possible to manufacture the high-grade steels like AHSS by EAF process. It means, when we produce the same high-grade steel in the EAF process, carbon dioxide emission can be reduced as 40% to compare with BF-BOF process. However, DRI consists of 10~20% of gangue and FeO so it needs much more energy input in EAF process. Therefore, it is important to enhance the EAF’s energy efficiency for Securing economic feasibility. Oxygen injection from EAF’s side wall is one of the straight ways to improve the energy efficiency. High speed oxygen injection can generate the gas jet into the EAF, and this jet has two main functions. First, Oxygen jet mutilates the side wall scrap for accelerate the scrap melting speed. Second, after the plat bath formation, oxygen jet refines the impurity, enhances the slag foaming for higher arc stability, and improves molten steel agitation for heat transfer. In this study, a method for setting the advanced oxygen input pattern was presented through index data that can accurately predict dissolution behavior. Also, It was verified that the oxygen jet improvement by the certain reformation of nozzle design.

Ernst, Daniel, Montanuniversität Leoben , Austria

Co-Author: Johannes Schenk, Montanuniversität Leoben • Michael Zarl, K1-MET GmbH • Isnaldi R. Souza Filho, Max-Planck-Institute for Iron Research

Abstract: Carbon Direct Avoidance (CDA), Smart Carbon Usage (SCU) and Circular Economy are strategic pathways that the European Steel Association's members created to reach a CO2-neutral European steel industry. Climate change can only be tackled by reducing the anthropogenic greenhouse gas emissions, particularly CO2 ones. The iron and steel industry must also contribute to mitigating CO2 emissions, as it accounts for 5.7% of the European Union's overall emissions and is even responsible for 7% of global anthropogenic CO2 emissions. To achieve the goals of the European Green Deal and reduce emissions by at least 55% from 1990 levels by 2030, today's steel industry and its processes must be completely transformed. Highly promising process technologies use hydrogen (H2) as the primary reducing agent instead of carbon-carrier substances (coke) to simultaneously reduce iron ores and achieve the climate target, thus following the CDA pathway. The Hydrogen Plasma Smelting Reduction (HPSR) exploits the highly energetic hydrogen species (e.g. H, H+) existing in a hydrogen-containing plasma arc as reducing agents for the ore. The high energy of such hydrogen plasma species helps overcome the reaction’s activation energy, leading to a 15 times higher reduction potential than the gaseous molecular hydrogen. The plasma species are created by the thermal energy of a DC-transferred arc between a hollow graphite electrode (HGE) and the melting bath, enabling a one-step direct production from iron ore to steel. Introducing iron ores with different pre-reduction degrees into the reaction zone (plasma/melt interface) influences the hydrogen utilization degree, the total process time, and the metal phase's microstructure. With this knowledge, optimal combinations of pre-reduction states via direct reduction and subsequent processing with hydrogen plasma to crude steel can be achieved to obtain the highest H2 utilization and optimal steel quality.

Esterhuizen , Andre, Tenova South Africa Pty Ltd, South Africa

Co-Author: Piet Jonker, TENOVA South Africa Pty Ltd • Marco Corbella, Tenova S.p.A.

Abstract: With the global steelmaking industry’s focus on the decarburization of the steel making process, Tenova has developed iBlue®, a novel technology that combines conventional smelting furnaces with the Energiron® Direct Reduction technology - jointly developed by Tenova and Danieli - to replace the blast furnace process, using low grade pellets (± 62% FeO) as virgin iron sources. To maximize the yield of the hot metal produced, and provide operators with a flexible plant design that can cater for a wide range of inputs, key design decisions are required to ensure an optimal flow sheet. This paper explains in detail the decision making process in the DRI melter design, touching on raw material feed requirements, metal handling, carbon balancing, electrical system design and management of the off gasses produced in the reducing atmosphere. These concepts will be evaluated from both a control volume and process design point of view. The conduction of the melter process is closely connected to the DRI production process and there are substantial benefits in the interconnection of the ENERGIRON® plant and the melter from an overall quality and efficiency perspectives. The paper analyzes the benefits of a closed furnace design for this application, as it operates in a reducing environment, allowing for minimal losses of FeO to the slag. Lastly, slag conditioning and management is described: matching the chemical composition requirements for the cement industry (not possible using an EAF) is a key benefit of this solution which can be truly considered as the evolution of the blast furnace technology. Key Words Hydrogen, DRI, HBI, BF, BOF, EAF, FMF, H2, reducing gas, carbon footprint, decarburization, ENERGIRON ZR, CCS, CCU, smelting reduction furnace, OSBF, ENERGIRON

Fang, Yuan, Baowu Group, China

Abstract: Twin roll strip casting and rolling is one of typical near net shape steel manufacture process. Baostrip® for low carbon steel have made breakthrough progress and achieved remarkable results during past 20 years. Baostrip® has gone through two stages. The first phase, which took more than 10 years, involved understanding the effects of the process parameters, chemical composition, and inclusion of steel on the initial heat transfer, sub-rapid solidification, castability, phase transformation, structure, and mechanical performance. A pilot plant equipped with 1200-mm-wide twin-roll caster was built for developing side dam, nozzle, and casting roll. The liquid steel is supplied by a 15t electric arc furnace, ladle furnace and Vacuum Oxygen Degass. More than 300 heats were trialed and more data, experience, and knowledge were obtained. A variety of steel grades such as silicon steel, low-carbon steel, high-strength low-alloy steel, medium-carbon steel, and medium-Mn steel were successively trialed. A series of models were built to control the uniform solidification on the casting-roll surface and uniform wear of the side dam, as well as to minimize fluctuation of the casting pool level and stabilize the separation forces.The second phase commenced in 2012. An industrial demonstration production line was put into operation in 2014, and has made remarkable achievements. Last year, Baostrip® obtained the first construction contract of commercial strip casting and rolling plant. This paper summarizes the results we obtained in the industrialized demonstration plant, and introduces the new project, and analyses development direction and ways of strip casting and rolling technology in future.

Faraci, Eros, Rina Consulting – Centro Sviluppo Materiali S.p.A, Italy

Abstract: The steel production trough electric arc furnace (EAF) plays an increasingly important role in modern steelworks concepts. Today the electric arc furnace steel of the overall steel production in the EU-27 is just over 40 % (59 Mtons/year). The share of the global steel production by EAF route is expected to increase due to its more flexibility, less investment and lower environmental impact respects to the BF-BOF steel production route. Moreover, on the ongoing projects, related to green steel production by Direct Reduction, Integration (DRI) of renewable electricity and hydrogen production (as SALCOS and HYBRIT projects) will provide many opportunities to increase the EAF steel production route but in order to catch these opportunities a strategy for decarbonization and thus sustainability for EAF steel production must be implemented. In this frame the main objective of DevH2forEAF, project founded by RFCS, is to set up and test a EAF burner fed with hydrogen to replace natural gas. This project is coordinated by: RINA Consulting – Centro Sviluppo Materiali SPA (RINA-CSM) and the partners are: 1) Rheinisch-Westfaelische Technische Hochschule Aachen (RWTH); 2) Compania Espanola de Laminacion Sl (CELSA); 3) Ferriere Nord SPA (FeNo); 4) Nippon Gases Industrial SRL (NG Ind.) 5) SMS group SPA (SMS) 6) AFV Acciaierie Beltrame SPA (AFV Beltrame) This project provides a comprehensive analysis of H2 hydrogen burner in EAF through the main activities: 1) Design and realization of EAF burners, able to work with NG/H2 mixture, up to 100% hydrogen (SMS) 2) Design and realization of H2 pipeline from the tube trailer to EAF in safety conditions (NG Ind.) 3) Analysis the performance of hydrogen burner in replacement of NG through experimental trials at lab and pilot scale (RWTH and CSM) an at two industrial sites (FeNo and CELSA). The final results of this project will represent a milestone for the utilization of H2 in steelmaking and the first key step for the decarbonization of the steel industry.

Fehlemann, Niklas, RWTH Aachen University, Germany

Co-Author: David Lenz, RWTH Aachen University • Yannik Sparrer, RWTH Aachen University • Markus Könemann, RWTH Aachen University • Sebastian Münstermann, RWTH Aachen University

Abstract: High-strength structural steels (from 960 MPa upwards) are becoming increasingly important in modern steel construction applications. These steel grades are particularly suitable for reducing sheet thicknesses of components and thus enabling more sustainable construction. The low-temperature properties are also of great importance, and a profound understanding is necessary in order to exclude the risk for catastrophic failure due to cleavage fracture in the component design. In this study, the low-temperature properties of a structural steel of type S960 were investigated. For this purpose, specimens of different stress states (including shear, plane strain and notched round bar) were quasi-static tested in a bath of liquid nitrogen at -196°C. The resulting properties were analyzed in terms of ductility and strength and compared with the same properties at room temperature. For this purpose, a failure locus based on stress triaxiality and lode angle parameter and equivalent plastic strain was fitted to the data. In addition, the critical cleavage fracture stress of the material is identified. The probabilistic nature of the low-temperature properties was captured using a cumulative Weibull distribution so that a locus for different failure probabilities can be determined. The results show a pronounced dependence on the stress state, which is more pronounced at cryogenic temperatures than at room temperature. In the last step, a comparison was made with a high strength a pipeline steel. Comparable tendencies were found at room temperature, but a clearly different behavior at low temperatures. This shows that the stress state dependence of the low-temperature failure properties is clearly material-dependent and large deviations can occur for different steel classes. These results can be used to calibrate damage mechanics simulation models, which can significantly accelerate efficient design of steel components for various applications.

Fein, Martin, Andritz AG, Austria

Co-Author: Andreas Argards, SSAB AB • Lubomir Slapak, Allisnet S.r.o.

Abstract: SSAB intended to improve the quality and productivity for their existing Continuous Annealing Line (CAL) in Borlänge, Sweden, so they chose ANDRITZ Advanced Furnace Control (AFC). A new generation of AFC was first time applied on SSAB’s CAL. It consists of a modular design with a newly developed cooling model and a brand new multi model predictive control. The precise physical model for all heating and cooling sections acts as virtual sensors, which provides real time trends of the temperature distribution within the furnace and acts as a huge source for Big Data. The multi model predictive control ensures collaboration between all models to enable constant high quality heat treatment by assuring maximum productivity. It runs in fully automatic furnace operation and optimizes line speed, heating power and blower speed for all furnace sections. The predictive capability of the model opens a lot of new opportunities for online and offline improvements of the production. Some examples, that have been developed together with SSAB, are the online compensation of the varying strip emissivity over the coil length and the optimization of the heat cycle recipes. Furthermore, the visualization of the prediction also facilitates operators to have a better situational awareness of the furnace operation. This paper reports on details of the installation of AFC at a CAL of SSAB and the resulting increase in quality and productivity.

Fein, Martin, Andritz AG, Austria

Co-Author: Andreas Rechberger, Andritz AG • Vasile Jechiu, Andritz AG • Philippe Reynes, Andritz AG

Abstract: This paper reports on a strategy of alternative heating solutions for a continuous galvanizing line in order to prevent any direct CO2 emissions, increase efficiency and production at the same time. This is possible by replacing common natural gas-fired radiant tubes with a new electrical heating system without modification of existing furnace setup, minimizing down-time and reducing the OPEX (lifetime increase and easier maintenance). The system – developed by ANDRITZ - is based on existing and reliable technologies and eliminates NOx emissions completely. In addition, to electrical heating, an advanced type of hydrogen-ready burners was developed to replace the consumption of natural gas on direct fired furnaces – combined with decreasing respective CO2 emissions – potentially using green hydrogen. The performance of the new Green Hydrogen burners has been validated with CFD simulations, confirmed by laboratory tests with full hydrogen operation. This internal development started 2 years ago has been confronted to customers, then validated during detail study in partnership with one of our long term and key clients. The study confirmed the expected results and even more, leading us to go further, building dedicated test furnaces and schedule industrial tests. The electrical test furnace is already in use to validate customer specific configurations in real operating conditions.

Fernö, Elina, Swerim AB, Sweden

Co-Author: Elina Fernö, Swerim AB • Xianfeng Hu, Swerim AB

Abstract: The ironmaking process utilising the blast furnaces releases a significant amount of CO2 into the atmosphere due to using coke/coal as reductants and fuels. Innovative technologies are needed to meet the Paris agreement and reduce CO2 emissions in the ironmaking process. Electrolysis, which employs electrons generated from electricity as the reductants, is one of these alternative technologies. When electricity produced from renewable sources is applied, and an inert anode is employed in the electrolysis process, the process will be completely green, yielding iron as a product and oxygen as a byproduct; meanwhile, no CO2 is released. In this study, we investigated the electrolytic reduction behaviors of pure chemicals (or synthetic chemicals) of wustite, hematite, and magnetite, as well as magnetite-type iron ore in the molten NaOH salt (kept at 500 °C). There was at Swerim (Luleå, Sweden) established a pilot-scale electrolysis reactor, in which the materials of interest up to 60 grams were tested at the cathode, and a graphite electrode was applied as the anode. A series of electrolysis reduction trials were conducted at a constant cell voltage of 1.7V to understand how iron oxides with different valence statuses are reduced and how the gangue materials in the iron ore can affect the electrolytic reduction process. The results show that iron oxides/ore can be reduced into metallic iron electrolytically in molten NaOH salt. There is a stepwise reduction of iron oxides from a high valence to a low one. The knowledge obtained in this study provides a better understanding of the electrolytic reduction behaviors of iron oxides/ore, thus assisting in developing a CO2-free molten salt electrolysis process for ironmaking when an inert anode is applied. Also, this study provides knowledge for the electrolytic reduction of other transition metal oxides in molten salt.

Ferraiuolo, Alessandro, Marcegaglia Carbon Steel S.p.A., Italy

Co-Author: Lorenzo Ferraiuolo, Mathematics - UNIBO

Abstract: ABSTRACT In the present paper is presented a novel physical approach aimed to evaluate the workpiece work hardening during rolling process. The evaluation of the work hardening offers the possibility to build up an incremental plasticity model to be applied for the investigation of microstructure evolution during actual industrial processing. The proposed approach is articulated into two steps: the first step it consists in introducing a new concept: the effective work hardening that includes the sum of two distinct additive contributions: 1) the microscopic work hardening, due to dislocations interaction with forest dislocation and 2) the plastic hardening/softening related to Von Mises plasticity condition under multiaxial stress state. The effective work hardening of the workpiece in the rolling process under plane strain conditions is evaluated on the basis of classic Orowan-Alexander rolling process equation and assuming the normal stress distribution along the roll bite as described by Bland-Ford equations. Following this approach, the equilibrium equation along the contact arc assumes the form of a differential equation (dk/dε)_eff=Ωk relating the effective work hardening with the workpiece yield stress times a factor Ω, named stability function, that is a function of the rolling process parameters and stress-strain path. The second step it consists in the microscopic work hardening evaluation subtracting, from the effective work hardening, the plastic hardening/softening under perfect plastic assumption. The novel incremental plasticity approach could be applied to many metallurgical applications such as strip microstructure evolution during hot rolling process, to design optimized rolling schedule, to investigate on strip failure in rolling process by plastic stability/instability analysis and finally to realize a smart rolling sensor. KEYWORDS: Effective work hardening, incremental plasticity, stress-strain path, plastic stability, smart rolling.

Fiedler, Andre, thyssenkrupp Steel Europe AG, Germany

Co-Author: Jan Vogt, Refratechnik Steel GmbH • Tim Kruell, Dominion Deutschland GmbH

Abstract: Due to premature wear accompanied by hot spots on the shell in the bosh and belly area of Blastfurnace 2 in Schwelgern a shotcrete repair by roboter became necessary. With a hearth diameter 14.9m and a production of up 12.000t/d Schwelgern BF2 is the largest BF in Europe. For the bosh and belly area that means a diameter of approx. 20m and a depth of 25m. This was the first time for this kind of repair in this area of a BF at Schwelgern. This work shall give an overview of the planning and the execution of the work on site done by thyssenkrupp Steel Europe AG, Refratechnik Steel GmbH and Dominion Deutschland GmbH. Which means on the one hand the planning of the blow-down process with the aim of not having to remove burden via tuyere area. The activities done in the casthouse if this should have been necessary and an overview of the success of the blow-down procedure Additionally it will be given an overview of why the applied refractory, Refrajetcrete with Hybrid technology from Refratechnik Steel GmbH, was chosen. The third point will focus on the used shotcrete roboter from the compamny of Dominion Deutschland GmbH. With the focus on why it was choosen and what changes had to be applied on the roboter to grant success on site for the use in the bosh and belly area.

Firsbach, Felix, Badische Stahl-Engineering, Germany

Co-Author: Andrea Pezza, Badische Stahl-Engineering • Per Lückhoff, Badische Stahl-Engineering • Peter van der Velden, Badische Stahl-Engineering • Patrick Hansert, Badische Stahl-Engineering

Abstract: Decarbonization of iron- and steelmaking needs different approaches for different steel plants and aggregates. It can be categorized into three pillars: 1) process optimization, 2) adapting existing technology, and 3) investing in new technology. This paper addresses the implementation of new EAFs into existing melt shops with a focus on EAF design possibilities, their up- and downsides, and the challenges of switching from BOF to EAF operation.

Fischer, Dennis, D.A.R. Metall AG, Germany

Co-Author: Felix Kaiser, RWTH Aachen University • Tim Reichel, RWTH Aachen University • Vladimir Vakulchuk , D.A.R. Metall AG • Pioh Cho, Genco Co. Ltd. • Herbert Pfeifer, RWTH Aachen University

Abstract: The steel industry produces with approx. 1,7 t Greenhouse Gas (GHG) emissions per 1 t crude steel around 10 % of all GHG-emissions worldwide. Thus, a transformation towards green steel production by replacing fossil- or carbon-based energy supply as well as feedstock by alternative resources, like renewable energy and hydrogen gas, is inevitable. However, this transformation is facing challenges since it requires significant technological changes and developments, which need expensive investments and will take around 10 to 15 years until they are completely implemented. To reduce the GHG-emissions already during this transition phase it is essential to modify individual processing steps and materials. Modifications in these process sections can be realised in short time and require low investments but can have a high impact on the reduction of GHG-emissions. Moreover, when the perspective of producing GHG-emissions is expanded beyond the borders of a local production facility onto the supply chain of input materials for steel production processes, there is an additional high potential reducing GHG-emissions. For instance, the replacement of natural resources by alternative input material with a low carbon footprint (CFP), like recycled or secondary raw material, will support lowering the GHG-emissions as well as conservation of resources. This contribution presents three possibilities to lower the GHG-emissions: The substitution of fossil coal by recycled plastic waste with a low CFP, utilization of recycled aluminium granules with a low CFP in combination with an efficient deoxidation injection method as well as innovative refractory materials, which does not contain carbon nor cement and show a higher durability in comparison to usual material. Based on various use cases within steel production considering blast furnace and electric arc furnace routes, the emission savings of the different solutions are presented.

Fischer, Lothar, SMS group, Germany

Co-Author: Martin Friedrich, SMS group • Stephan Six, SMS group • Jochen Wans, SMS group • Matthias Kampf, SMS group

Abstract: SMS group presents an overview of intelligent technologies. HD LASr [strand], HD mold and HD scan are essential instruments for the sustainable improvement of slab quality. HD stands for High Definition or the possibility to get a more detailed insight into the process with the action option. The HD products accompany you throughout the entire process. The positive feedback from our customers clearly shows the intensity with which SMS group develops continuous casting for current and future challenges. With the aim of making the checking easier, more precise and reliable the digital aligning assistant HD LASr [strand] has been developed basing on the well-proven 3D Lasertracker measuring technology. HD LASr [strand] can be used for measuring the strand guide in the caster itself: the position of the surface of mold copper plates, mold foot rollers and segment rollers of the vertical strand guide part. The HD moldFO - fiber optcal mold monitoring system from SMS group provides high-resolution view insight into the solidification process. Operator guiding assistance of the HD moldFO contributes to a safe plant protection serving for high yield production of prime quality slabs. The next generation HD moldFO+ stands out with crucial enhancement, namely permanent connection between fiber optics and evaluation unit. A fiber optical cabling between the mold and PLC-Room is not needed, so it is more maintenance-friendly. HD scan is the ultrasonic measuring system of the future for classifying the internal quality of cast products. The quality of cast products is the crucial economic factor not only for manufacturers and for retailers, but for further processing companies and consumers too. The software to evaluate the data produces objective, valuable reports on the internal quality of cast products. HD scan is easy to operate, the method is reliable, and the results are reproducible.

Flament, Sebastien, CRM Group, Belgium

Co-Author: Henk Bolt, Tata Steel Nederland Technology B.V • Gisele Walmag, CRM Group

Abstract: Back-up rolls (BURs) in cold and temper rolling mills often exhibit very inhomogeneous wear rates over their barrel length. Wear rates and resulting BUR wear profiles are usually not understood and (thus) not well predicted. The BUR wear profile has, in turn, a large effect on the local work roll/back-up roll (WR/BUR) contact stress distribution along the BUR barrel length. This crucial parameter for rolling contact fatigue is also unknown as well as also highly inhomogeneous. Consequently, also the onset of local rolling contact fatigue (RCF) at the BUR surface is poorly predicted and may in fact differ strongly between consecutive mill campaigns of the same BUR, so that mills struggle to define adequate (= safe and economical) practical maximum BUR campaign length limits. An assessment of BUR wear and rolling contact fatigue phenomena by examination of worn BUR surfaces in association with rolling mill process data and profiles has enabled to determine the degradation mechanism of various rolls in different kinds of cold rolling and temper mills, stand positions and materials. This analysis, based on light optical microscopy, hardness, roughness and profile measurements was performed on-site at Tata Steel in IJmuiden. Further analysis of BUR wear and contact fatigue damage accumulation in the sub-surface region was enabled by microscopic analysis in cross section of samples extracted from two scrapped BURs, an ICDP BUR and a 3%Cr forged steel BUR. This paper will give an overview of back-up rolls degradation, surface aspects, mechanisms and important differences of selected cold and temper rolling mills.

Dr. Fleischanderl, Alexander, SVP, Head of Green Steel, Chief Technology Officer Upstream, Primetals Technologies Austria, Austria

Abstract: Steel is an invaluable material for many sectors. However, in the context of the climate crisis, the sector has come under increased scrutiny due to its reliance on carbon-intensive fossil fuels, primarily coal. Strong political pressure guided by a strict taxonomy as increasing carbon emission cost and requirements from the steel demand side have motivated major steel producers to develop a dedicated decarbonization roadmap, expressing the strategic way to net-zero. The steel sector’s actual sustainability achievements and the technology options for the transition including their technology readiness level (TRL) and respective timeline will be discussed. However, the transition pathways are facing multiple roadblocks, which are different in the regions around the globe. One of the roadblocks is the availability and quality of raw materials like scrap and iron ore, another one the availability and cost of renewable energy and low-carbon hydrogen, the approach to carbon capture utilization and storage (CCUS) as well as the available regional taxonomy and political support. The steel growth rate (CAGR) until 2050 is modest, but the technology transition is huge. Might the major OEMs become a bottleneck? Digitalization plays an enormous role in the transition and educated young engineers will become another limitation. Some regions have realized their advantages related to cheap energy and raw materials. The energy intense up-stream process steps might be relocated to such regions and green metallics might be traded to a much larger extent. Despite of all these limitations the first green steel projects have been kicked-off and are under implementation. A status report will be provided.

Fogelström, Julia, Swerim AB, Sweden

Co-Author: Du Sichen, Hybrit Development AB

Abstract: Direct reduction of iron ore using hydrogen is one process that can produce iron from virgin materials and at the same time reduce CO2 emissions. In a shaft furnace, iron ore pellets are loaded at the top while hydrogen is introduced at the lower part. Pellets are slowly passing through the reactor and experience a temperature gradient ranging from low to high, i.e., non-isothermal reduction. Only a handful of studies have been performed to investigate the effect of non-isothermal reduction, and none focus on systematic analysis. Very few comparisons between isothermal and non-isothermal reductions have been made. To better understand the kinetics of non-isothermal reduction for process optimization, a preliminary study including both non-isothermal and isothermal experiments using pure hydrogen is conducted. The reduction experiments are performed in a resistance-heated furnace at 1173 K or between 723-1173 K for the isothermal and non-isothermal experiments, respectively. Non-isothermal reduction is much slower than isothermal reduction, as expected. The heating rate greatly affects the reduction rate, increasing with increasing heating rate. The mechanisms during the isothermal and non-isothermal reductions are discussed and compared. The reduction rate slows down at the later stage of reduction. At this point, the non-isothermal reduction rate is lower compared to isothermal reduction. To further examine the effect of heating rates, the microstructure of reduced samples is studied using a scanning electron microscope. The microstructure develops over time as the pellet is reduced, this is true for both isothermal and non-isothermal reduction. The heating rates have a limited effect on the microstructure. It would be difficult to capture and model the reduction behavior using only isothermal reduction experiments. Thus, studying non-isothermal reduction is needed. When optimizing the reduction in a shaft furnace, considerable attention should be directed toward the effect of the heating rates.

Fornasari, Lorenzo Engel, Ternium, Brazil

Co-Author: Roberto Gerardo Bruna, Ternium • Camila Gisele Lalli, Ternium • Maite Ochoa, Ternium • Bruno Pinheiro da Silva, Ternium • Andres Aused, Ternium

Abstract: Being able to accurately predict metallurgical coke properties for different parent coal blends is an important part of optimizing an integrated steelmaking plant production costs and ensuring blast furnace process safety. However, it is challenging to balance the economic pressures to use different coals and different blend compositions, the need for minimal product quality and the complexities of the coke-making process. The present work aims to construct coke quality models based on traditional analyses of constituent coals and some process parameters to enable better prediction for a wide range of blend characteristics. To this end, historical production data for process parameters and qualities of coke, coal and petcoke documented in a by-product coking plant were collected and processed using data mining and machine learning techniques. Attempts were made to model coke strength after reaction (CSR), stability and hardness indices by combining domain knowledge with feature engineering, feature selection algorithms and proposing three different models for each quality index - multiple linear regression, gradient boosted decision trees with XGBoost and gradient boosted linear trees with Light GBM. Cold strength models, especially those created using gradient boosting techniques, attained reasonable predictive ability. It is concluded that despite the inaccuracies surrounding industrial data collection, data mining and machine learning techniques provide a viable and promising framework for coke quality modeling in mature and well-documented processes.

Fornasari, Lorenzo Engel, Ternium, Brazil

Co-Author: Ricardo Vieira Regis De Almeida Martins, Ternium • André Costa e Silva, Universidade Federal Fluminense • Bruno Cerchiari, Ternium • Raissa Salgado, Ternium

Abstract: As market demands and competitiveness increases worldwide, steelplants are constantly adapting and innovating to meet higher quality specifications, reach new market shares and achieve cost reductions. As such changes occur, we see renewal in the Steel Industry and gain room to find unprecedented and/or uncharted issues. It was observed at Ternium Brasil Steelplant the occurrence of Chromium Pick-up unrelated to charged materials (i.e. contamination) in the Ruhrstahl Heraeus Vacuum Degasser (RH) during the treatment of electric steels. The Chromium pick-up occurrences were sufficiently high to surpass the client’s specified residual level. As chromium oxides are present in the RH refractories, the present work aims to evaluate the thermodynamic stability and kinetic mass transfer aspects of MgO, Cr2O3, Al2O3, SiO2 systems in contact with Steel. The results indicated that chromium oxide is not stable in the presence of well deoxidized steels, including non-electric grades. Still, a strong influence of silicon on the chromium pick-up was observed. The thermodynamic analysis indicated that the silicon addition to MgO, Cr2O3, Al2O3 systems creates liquid-phases for the typical temperature ranges of steel treatment. This may impact on the kinetics of refractory wear and dissolution. Furthermore, the analysis indicated the high-silicon content of the electric steels lowers the oxygen potential in steel. Besides, silicon reduces the surface energy between steel and refractories, increasing the latter’s wettability. To control the occurrence of chromium pick-up, mass transfer models were formulated for solute transport in steel and for refractory erosion as rate-limiting steps. The models were then used to optimize both the acceptable charge composition and the RH processing time when refining electric steels with controlled chromium residuals. The introduction of these control measures dramatically reduced the deviations associated with high content of residual chromium in electric steels.

Fouarge, Hubert, CRM Group, Belgium

Co-Author: Frédéric van Loo, CRM Group • Jan Wiencke, ArcelorMittal Maizières Research • Maria Martinez Pacheco, Tata Steel Nederland Technology B.V • Loredana di Sante, Rina Consulting – Centro Sviluppo Materiali S.p.A

Abstract: In order to allow steelmakers to comply with ever stringent environmental constraints, TACOS project aims at evaluating solutions bringing significant decrease of CO2 with consequently decrease of others main pollutants (a.o. NOx, SOx, VOC’s, dioxins and dust emissions). Following alternative heat inputs are investigated : I. Alternative solid fuels with or without pre-processing’s; II. Waste gas recirculation (case studies are ArcelorMittal Fos, selective lay-out and Tata Steel IJmuiden, non-selective lay-out); III. Combustible gases for injection at strand surface; IV. High temperature fumes produced in an external combustion chamber. Combinations of these solutions will also be tested to reached a replacement of 100% of the solid fuel. For evaluation of the impact of these solutions on sintering process performances and emissions, tasks consists in modelling work (mathematical model), lab trials, sinter pot trials and industrial measuring campaigns and trials. These solutions have significant impacts on Blast Furnace process, so a special focus is also placed on their impact on sinter quality (especially on its vertical segregation) and BF performances. For that purpose a wide set of complementary tools not use in usual industrial practice is available amongst the project partners. At this stage of the project, a replacement rate of the solid up to 80% was tested for the selected alternative solid fuels (pyrolyzed biomass) without significant impact on sinter quality and productivity. Based on the pot trials results, industrial trials will be performed in ArcelorMittal Gent. Blast furnace gas injection at sinter strand surface was tested up to 10% replacement of the solid fuel while the hot fumes injection at strand surface allowed to reach 35% with limited productivity drop. This research is funded by the Research fund For Coal and Steel (RFCS), project # 847322-1, June 2019 to June 2023.

Franz, Klaus, Primetals Technologies Germany, Germany

Co-Author: Gerd Becker, Primetals Technologies Germany • Klaus Weinzierl, Primetals Technologies Germany GmbH

Abstract: "In the production of green steel, it is necessary to provide green hydrogen in sufficient quantities. This can be produced from green electricity by means of electrolysis. It is particularly important to produce the hydrogen as cost-effectively as possible. To achieve this, on the one hand the electrolyzer has to be operated at the highest possible utilization rate, and on the other hand only when energy costs are low. This means a conflict of objectives, which can be resolved by supplementing the electrolyzer with a battery energy storage system. This combination requires an intelligent predictive control system that actually operates this production process at its optimum cost. The paper describes a model-predictive approach that takes into account energy costs, capital costs, and the costs due to wear of the entire plant. The approach is universal and can easily be extended to include other plant components, such as a direct reduction plant, a hydrogen storage unit or a wind power plant. Simulation results show the advantages of the approach."

Fredi, Francesco, Feralpi Group, Italy

Co-Author: L. Angelini, Feralpi Group • Piero Frittella, Feralpi Group • A. Landini, Feralpi Group • M. Fusato, Feralpi Group • G. Foglio, Feralpi Group • C. Di Cecca, Feralpi Group • M. Tellaroli, Feralpi Group • E. Tolettini, Feralpi Group • Mattia Bissoli, Tenova S.p.A. • Mauro Gizzi, Tenova S.p.A. • Elia Gosparini, I. Blu Spa • Filippo Cirilli, Rina Consulting – Centro Sviluppo Materiali S.p.A • M. Bersani, Acciaierie di Calvisano

Abstract: The substitution of the use of carbon sources in Steelmaking became in last years an even more important topic considering the necessity both to increase the possibility of reuse of the residues also from other sector and also to reach a condition of strongly reduction of the global use of carbon sources to arrive at a condition of zero CO2 emissions. In particular, Feralpi Group has followed this route since several years starting with trials of basket charging of alternative materials arriving in last configuration to totally substitute the coal injected by wall mounted lances with polymers obtained by the plastic residues. Thanks to this substitution Feralpi Siderurgica became fist EAF plant with only polymer injected by wall mounted lances and able to eliminate the solid natural carbon sources to enable a correct production process and an appropriate slag foaming. In this way enabling the demonstration of a feasible industrial approach for the use of alternative materials Here the activity of the first period of the OnlyPlastic project is presented. The industrial injection system is described, together with a new injector able to efficiently deliver the plastic residues into the Feralpi Lonato EAF, with the aim of promoting the reduction process and the slag foaming in a circular economy approach. The paper includes also the design and realization of an industrial injection system and a new injector able to inject efficiently the material into EAF to promote reducing process and slag foaming. Keywords: Steelmaking, EAF, Slag foaming, Circular Economy, Residues Coal Substitution, Injections, Polymers

Frittella, Piero, Feralpi Group, Italy

Co-Author: L. Angelini, Feralpi Group • A. Landini, Feralpi Group • G. Foglio, Acciaierie di Calvisano • C. Di Cecca, Feralpi Group • M. Tellaroli, Feralpi Group • G. Tsymokh, Feralpi Group • B. Cinquegrana, Feralpi Group • F. Fredi, Feralpi Group • M. Bersani, Acciaierie di Calvisano • C. Senes, Acciaierie di Calvisano • F. Guerra, Acciaierie di Calvisano • G. Miglietta, Acciaierie di Calvisano • V. Duro, Acciaierie di Calvisano • A. Ventura, Rina Consulting – Centro Sviluppo Materiali S.p.A • D. Ressegotti, Rina Consulting – Centro Sviluppo Materiali S.p.A • F. Morandini, Feralpi Group

Abstract: In modern steel productions the necessity to improve process performances became more and more a relevant target for both improvement of single product production in terms of quality and costs and also to enable variation in production scheduling thanks a flexible assessment of operating practices adopted. To enable the improvement on this approach a deeper understanding of the process phenomena occurring during the production is necessary to be able to understand which actions are necessary to improve the effectiveness of the reactions and heat transfer. For this reason the approach followed in Feralpi included different steps passing through development of modeling for the different process phases, implementing these modelling in off-line prediction model and online process control and including capability to describe process guidelines as support to the operators during the production. In particular these have been realized for the three main process steps EAF, LF and Continuous casting in order to be able to modify operating practices thanks to prediction model and to support the on-line process control thanks to derived trends KPI’s, in particular for both sites of Feralpi Siderurgica and Acciaierie di Calvisano. Furthermore a through process view is necessary to respect the process/quality constraints aiming at improvement of performances and productivity. Acciaierie di Calvisano and Feralpi Siderurgica strongly address its productions developments with adoption of new technologies and solutions Industry 4.0 for data analysis and process control also supported by RFCS funding scheme in the funding R&D projects. With the contribution of the R&D department, process technology, production areas and research partners, in Feralpi predictive mathematical models have been created for production phases and whole steelmaking process. This has been done internally in order to be able to better setup the optimal operating practices for each process phases.

Frixione, Enrique, OG Technologies, Inc., United States

Co-Author: Chang Tzyy-Shuh, OG Technologies, Inc. • Michal Podermanski, Moravia Steel a.s

Abstract: In 2018 and 2019, Třinecké Železárny implemented a project to replace the surface inspection equipment using eddy currents in the two-strand wire rod rolling mills. The imaging-based surface inspection system was selected for installation in the wire rod mill based on its proven defect detection capabilities in many SBQ wire mills. The first unit was installed in 2018, with a second installation to follow in 2019. The wire rod mill quality team at Třinecké Železárny found the range of quality data, including images of defects, to be beneficial. In addition to real-time detection and alarms resulting in mitigation of quality failures, the newly available surface quality data has led to the resolution of various surface quality issues and the development and implementation of a coil grading model based on customer requirements, wire diameter, material grades and surface quality data. The results of the quality scorecard, along with images of defects, are displayed on a large screen at the quality control station, providing all line operators across all mill shifts with a clear, consistent and repeatable assessment of the quality of each rolled coil. The introduction of imaging-based surface inspection systems, coupled with improvements to the rolling process that enable surface quality data, has contributed to the best quality performance in 2021 since the wire rod mill began operations in the mid-1970s. This document maps the processes, experiences and successes of surface quality improvement at the wire rod mills of Třinecké Železárny.

Fuchs, Hagen, Primetals Technologies Germany, Germany

Co-Author: Ali Hegazy, Primetals Technologies GmbH • Michel Hein, Primetals Technologies Germany • Hans-Jörg Krassnig, Primetals Technologies Germany

Abstract: Fueled by net-zero prompts and to comply with the most stringent environmental targets, the world is about to witness a fast-paced transition into green steelmaking. DRI-based EAF route will play a crucial role in this green steel transition due to its significantly lower carbon footprint compared to the integrated route, while still ensuring the highest product quality. This paper will illustrate the position of DRI and EAFs within the green steel market regarding raw material quality, feedstock market, and CO2 emissions. The paper will also discuss the process design for DRI-based EAFs and provide an inside on the combination with multiple direct reduction technologies such as MIDREX, HyREX, and HYFOR. Features of the latest state of the art 220-t DRI-EAF by Primetals Technologies for Salzgitter Flat Steel in the heart of Europe will be highlighted (start-up in Y2025). Latest operational results will be reviewed, including project execution, productivity, consumption figures, slag control, product quality, and maintenance for cold and hot DRI-based EAFs from Primetals Technologies.

Gabriel, Matthias, Metso Outotec Oy , Germany

Abstract: Most forecasts for the global steel industry agree that the steel production will grow until 2050 by another 50%. Scrap smelting and the direct reduction route will account for the lions share of the growth, but the absolute amount of steel produced with the blast furnace route will remain almost the same. This shows that iron ore pelletizing will keep its paramount role to deliver high quality feed material for direct reduction shafts and blast furnaces. Amid the transition of the steel industry towards net-zero carbon, the pelletizing technology must also reduce their own carbon footprint and comply at the same time with the increasing quality requirement for the pellets. Metso Outotec as undisputed leader since the invention of pelletizing technology follows with the NextGen Pelletizing the clear vision to strive for the carbon neutral and fully autonomous pellet plants of the future. For the CO2 reduction the focus is lying on a further increase of the energy efficiency and heat recuperation of the induration process, new combustion concepts as well as the replacement of fossil fuels by means of Hydrogen burners or the substitution of solid fuel by biocarbon. Energy efficiency is also improved by the further implementation of new digital solutions. Metso Outotec’s proven advanced process optimizer Optimus is constantly complemented by new modules like the online measurement and control of the green pellet size, the pellet mix plasticity or the quality of the hardened pellets. All this performance improvements have also significant effects on the process stability and flexibility, the plant productivity and the product quality and finally on the operational cost.

Gaiser, Georg, Montanuniversität Leoben, Austria

Co-Author: Peter Presoly, Montanuniversität Leoben • Christian Bernhard, Montanuniversität Leoben

Abstract: Reducing CO2 emissions in steel production is one of the major challenges for the European steel industry in the upcoming years, whereby the remelting of scrap in electric arc furnaces is the most important bridging technology. Depending on the scrap type, steel scrap contains different levels of undesirable by-elements, also referred to as tramp elements. Technical and economic limitations lead to non-negligible tramp element contents in the steel. Those can affect high-temperature oxidation mechanisms in casting, rolling and annealing processes, leading to various types of internal oxidation phenomena and the formation of (liquid) phases at the interface. Within the scope of the present publication, oxidation experiments for different steels containing tramp elements were performed by means of thermogravimetric analyses. The influence of several time-temperature cycles and atmospheres were analysed. Particularly noteworthy are the experiments with an oxidation atmosphere simultaneously consisting of synthetic air and water vapour. In the presence of water vapour, oxidation intensifies, leading to a higher accumulation and formation of metallic copper phases at the interface and along grain boundaries. The results provide meaningful data to improve the understanding of high-temperature oxidation mechanisms in steel processing with a particular focus on continuous casting and serve as a basis for further experiments.

Garitaonandia Areitio, Erika, AZTERLAN Metallurgy Research Centre, Spain

Co-Author: Erika Garitaonandia, AZTERLAN Centro de Investigación Metalúrgica

Abstract: The thermocline Thermal Energy Storage (TES) systems are core elements to boost renewable energies and to improve the efficiency in energy intensive industries. Among TES technologies, air based packed beds storage system represent a promising option since they allow using low-cost materials. The steel slag, a byproduct from the steel production, represents an interesting option as filler material since it fulfils the criteria established in the International Energy Agency (IEA) for TES material, that consist on being inexpensive, available in large quantity without conflict of use, stable up to 1000 °C, compatible with heat transfer fluids and non-toxic. Preceding works have also revealed suitable thermo-physical and mechanical properties to be used as storage material for sensible heat transfer in packed beds. However, one of the critical aspects often not addressed is the durability of the filler material (slag particles) subjected simultaneously to mechanical and thermal stresses over a large quantity of charging and discharging operations. During cyclic thermal charging and discharging, the slag inside the tank is subjected to heavy loads at high temperatures and undergo thermal expansion and shrinkage, which can lead to individual particle degradation and also damage of the tank. For this purpose, different model approaches and tools are addressed in this paper. Specifically designed test rig is introduced in order to test long-term mechanical stability of the steel slag under thermal and mechanical fatigue. Acknowledgements This work has been supported by LIFE programme of the European Union through the Project LIFE20 CCM/ES/001733 ( (https://www.hi4s-life.eu/)

Ge, Sa, Hatch Ltd., Canada

Co-Author: Kamal Joubarani, Hatch Ltd. • Terrence Koehler, Hatch Ltd. • Ian Cameron, Hatch Ltd. • Chris Walker, Hatch Ltd. • Kyle Chomyn, Hatch Ltd.

Abstract: The future of steelmaking requires changes to existing integrated process flowsheets and application of new technologies to achieve significant reduction of greenhouse gas (GHG) emissions, i.e., green steel production. One such novel approach is the use of direct reduced iron (DRI) coupled with an electrical smelting furnace (ESF) to produce hot metal for downstream steelmaking, and thus replacing the blast furnace (BF) – the biggest GHG emitting process step in the value chain. The DRI-ESF process capitalizes on the lower Scope 1 GHG emissions from direct reduction and electric furnace processes versus BF, as well as the effective gangue rejection and slag valorization capability of ESF to improve raw material flexibility. The complexity of the iron and steel value chain and the rapidly evolving decarbonization technology landscape mean that the implementation of the DRI-ESF concept requires bespoke flowsheet development and thorough assessment of many potential options to be effective. The present study examines various potential flowsheets centred around the DRI-ESF concept, considering the key choices in flowsheet development such as DRI reductant (hydrogen or natural gas or both), specification of intermediate product, grade and type of iron ore, ESF slag valorization, downstream steelmaking technology, and the ultimate transition to ESF-based direct steelmaking. High level process and cost models were developed to simulate archetypal flowsheets, and these flowsheet cases are critically assessed with emphasis on comprehensive economics, overall GHG emission benefits, and level of technical / implementation risks. Potential risk mitigation options, enabling / synergistic technologies, and preferred implementation scenarios were also identified and discussed.

Geach, Paul Mark, Primetals Technologies UK, United Kingdom

Abstract: "Top fired stoves bring a number of operational advantages and therefore continue to increase in popularity. Various designs have been developed over recent years by a number of technology companies, with differing degrees of successful implementation. This results in an opportunity to identify the strong points of certain designs, and to have confidence in installation and operation with reference to particular designers. This paper will define the key features of a well-designed and constructed top fired stove, at the same time identifying the benefits (and problems) of different designs in terms of the stability of refractory construction, burner design, stove efficiency, environmental and CO2 emissions and operational longevity. The paper will identify why Primetals Technologies in collaboration with Yuxing Engineering & Technology propose particular designs of top fired stove, and why these designs can be trusted for implementation around the world. "

Gelmini, Mario, BM GROUP POLYTEC S.p.A., Italy

Co-Author: Ion Rusu, BM GROUP POLYTEC S.p.A. • Tiziano Bagozzi, BM GROUP POLYTEC S.p.A.

Abstract: The developed robotic system allows to easily reach the best pick-up point, depending on the plant layout. The cut can be carried out using different techniques, based on the type of material, the cutting quality required or based on the target performance (Circular or band saw, Shear, oxyacetylene cutting torch, Laser) The vision system that performs 2D / 3D scanning, identifies the arrival position of the material to be cut and can integrate a partial control of the sample in terms of size. The option of the robot mounted on an autonomous vehicle allows the automated handling when samples need to be taken from different points of the plate or from different plates and the automated samples’ handling to the lab station.

Gelmini, Mario, BM GROUP POLYTEC S.p.A., Italy

Co-Author: Ion Rusu, BM GROUP POLYTEC S.p.A. • Tiziano Bagozzi, BM GROUP POLYTEC S.p.A.

Abstract: The fully automated robot performs safely, remotely and autonomously different tasks on the casting floor. The system is able to identify the nozzle position into the space using a 3D machine vision system, to position the ladle shroud, oxygen lance the nozzle in case of corks, to take temperature and sampling and to distribute powder on the tundish. A smart solution that improves operator's safety on red zone area and efficiency.

Ghafoori, Elyas, Leibniz University of Hannover, Germany

Co-Author: H. Dahaghin, University of Tehran • C. Diao, Cranfield University • N. Pichler, Empa, Swiss Federal Laboratories for Materials Science and Technology • L. Li, Empa, Swiss Federal Laboratories for Materials Science and Technology • M. Mohri, Empa, Swiss Federal Laboratories for Materials Science and Technology • J. Ding, Cranfield University • S. Ganguly, Cranfield University • S. Williams, Cranfield University

Abstract: In this study, a directed energy deposition (DED) process called wire arc additive manufacturing (WAAM) is employed for the fatigue strengthening of damaged steel members. Three steel specimens with central cracks were tested under a high-cycle fatigue loading (HCF) regime: (1) the reference specimen; (2) the WAAM-repaired specimen with an as-deposited profile, and (3) the WAAM-repaired specimen machined to reduce stress concentration factors (SCF). The corresponding finite element (FE) simulation of the WAAM process was calibrated using static experimental results, which revealed the main mechanism. The process was found to introduce compressive residual stresses at the crack tip owing to the thermal contraction of the repair. The FE results also revealed that stress concentration exists at the root of the as-deposited WAAM; this stress concentration can be mitigated by machining the WAAM to a pyramid-like shape. The fractography analysis indicated that the cracks were initiated at the WAAM-steel interface, and microscopic observations revealed that the microcracks were arrested by the porosities in the melted interface. The results of this pioneering study suggest that WAAM repair is a promising technique for combating fatigue damage in steel structures.

Ghafoori, Elyas, Leibniz University of Hannover, Germany

Co-Author: N. Pichler, Empa, Swiss Federal Laboratories for Materials Science and Technology • L. Li, Empa, Swiss Federal Laboratories for Materials Science and Technology • C. Huang, Imperial College London • D. Ferrari, Empa, Swiss Federal Laboratories for Materials Science and Technology • E. Chatzi, ETH Zurich • L. Gardner, Imperial College London

Abstract: Wire arc additive manufacturing (WAAM) is a metal 3D printing technique that is well recognised in the construction sector for its high efficiency, cost-effectiveness and flexibility in build scales. However, there remains a lack of fundamental data on the structural performance of WAAM elements, especially regarding their fatigue behaviour. A comprehensive experimental study into the fatigue behaviour of WAAM steel plates has therefore been undertaken and is reported herein. Following geometric, mechanical and microstructural characterisation, a series of WAAM coupons was tested under uniaxial high-cycle fatigue loading. A total of 75 fatigue tests on both as-built and machined coupons, covering various stress ranges and mean stress levels, have been conducted. The local stress concentrations in the as-built coupons, induced by their surface undulations, have also been studied by numerical simulations. The obtained fatigue test results were analysed using constant life diagrams (CLDs) and S-N (stress-life) diagrams, based on both nominal and local stresses. The CLDs revealed that the fatigue strength of the as-built WAAM steel was relatively insensitive to the different mean stress levels. The S-N diagrams showed that the surface undulations resulted in a reduction of about 35% in the fatigue endurance limit for the as-built material, relative to the machined material, and a reduction of about 60% in the fatigue life for a given stress level. The as-built and machined WAAM coupons were shown to exhibit similar fatigue behaviour to conventional steel butt welds and structural steel S355, respectively. Preliminary local stress-based and nominal stress-based S-N curves are also proposed for the WAAM steel.

Gharagouzlou, Javad, Hormozgan Steel Company, Iran, Islamic Republic of

Co-Author: Seyyed Asghar Madani, Hormozgan Steel Co • Mohammad Sharif Sharifian, Hormozgan Steel Co • Ali Keshavarzi, Hormozgan Steel Co • Esfandiar Pourali, Hormozgan Steel Co • Mohammad Molabeyk, Hormozgan Steel Co

Abstract: Despite the existence of research sources on tundish hot corrosion in silicon killed steel, there are few researches on this issue in aluminum killed steel. In this research, using X-ray Diffraction, the main phases formed as a result of the reaction of slag-tundish mass have been investigated and formation causes of these phases and practical solutions to reduce the corrosion of tundish plaster are presented. According to the obtained results, monticellite phase is the main factor that causes the dissolution of MgO grains in the slag and the corrosion of tundish mass. And the end, the solutions to reducing of tundish mass corrosion in Aluminum killed steel are explained.

Giese, Marcel, Federal Institute of Materials Research and Testing, Germany

Co-Author: Volker Wesling, Clausthal University of Technology • Thomas Kannengießer, Federal Institute of Materials Research and Testing • Dirk Schröpfer, Federal Institute of Materials Research and Testing • Kai Treutler, Clausthal University of Technology • Antonia Eissel, Clausthal University of Technology

Abstract: The targets for reducing CO2 emissions are closely linked to the development of highly efficient and economical steel components in plant, process and power plant technology, which require wear protection coatings tailored to the application and steel material for high combined corrosive, tribological, thermal and mechanical stresses. In addition to increasing demands to replace conventional cobalt alloys with nickel alloys as a result of price and supply risks, there is a growing demand in industry for defined functional surfaces of high quality for these coatings. Milling is a standard process for finish machining. The desired properties of wear resistant alloys imply significant challenges for the milling process due to high tool wear and surface defects. Besides the hardness of the coating materials, especially due to the precipitations, inhomogeneous, anisotropic weld structures of the claddings lead to further deteriorations of milling processes due to unstable milling conditions and process forces. A joint project of BAM and ISAF of TU Clausthal (Fosta P1550/IGF 21959 N) investigates the optimization of these challenging machining conditions by means of alloy modifications of the welding powder for plasma transferred arc cladding, without reducing the wear protection potential and using ultrasonic assisted milling process. In this paper, the influence of the microstructure and precipitation morphology adjusted by means of alloy modification on machining is investigated. The alloy used is a NiCrMoSiFeB alloy (trade name: Colmonoy 56 PTA). Through metallurgical investigations and in-situ measurement of cutting forces and temperatures at the cutting edge during the milling process as well as the subsequent investigation of tool wear and surface integrity, a detailed analysis and correlation between microstructural properties and machinability is feasible. The findings allow recommendations for standards and processing guidelines, enabling safe and economical production of highly stressed steel components with non-critical, cost-reduced materials.

Glaser, Björn, KTH Royal Institute of Technology, Sweden

Co-Author: Marcus Holmström, KTH Royal Institute of Technology • Herbert Köchner, KTH Royal Institute of Technology/ASENSO • Daniel Sundberg, ScanArc Plasma Technologies AB • Asier Arteaga Ayarza, Sidenor Investigación y Desarrollo • Nora Egido Perez, Sidenor Investigación y Desarrollo • Raffaello Pio Iavagnilio, Politecnico di Bari

Abstract: Marcus Holmström1, Björn Glaser1, Herbert Köchner2, Daniel Sundberg3, Asier Arteaga4, Nora Egido Perez4, Raffaello Pio Iavagnilio5 1Kungliga Tekniska Högskolan, Department of Materials Science and Engineering, Brinellvägen 23, 10044 Stockholm, Sweden 2ASenSo GmbH, Am Birkengraben 12, 50259 Pulheim, Germany 3ScanArc Plasma Technologies AB 4Sidenor Investigacion y Desarrollo SA 5Politecnico di Bari Keywords: Ladle preheating, plasma heating Preheating of steelmaking ladles is a prerequisite to minimize thermal shock and wear of the refractory and to reduce temperature losses of the liquid steel during tapping and holding times. Standard preheating technology using conventional gas-fired burners is unfavorable regarding thermal efficiency (5-15%), energy consumption and emissions. A novel technique using plasma heating offers a more flexible ladle preheating procedure with a higher thermal efficiency (80-95%) and aiming at reduced gas consumption and emissions. The current RFCS pilot and demonstration project PLASMAPILOT investigates the necessities, technical requirements and opportunities of ladle preheating procedures using plasma by combining measurements, numerical modelling of ladle preheating processes and pilot trials at a plasma heater test rig with a full-scale steelmaking ladle. First results will be presented on assessment of plasma technology with regards to economic and environmental benefits, together with results from plant trials and laboratory investigations on refractory lifetime.

Glodek, Peter, GEA Bischoff GmbH, Germany

Co-Author: Jens Lange, GEA Bischoff GmbH • Marcel Zillgitt, GEA Bischoff GmbH

Abstract: With the goal of reducing greenhouse gases to prevent global warming above 2 °C, industry is facing an unprecedented challenge. In this context, the reduction of CO2, as the main driver of global warming, represents a sensible and sustainable solution from many points of view. On the one hand, there is increasing national and international pressure regarding energy and CO2 saving solutions. On the other hand, there is also an opportunity to reduce operating costs in long term by a new sustainable orientation. Particularly in the context of sharply rising certificate costs for CO2, a trend is emerging that a decisive step must be taken in the direction of sustainable and ecological industrial processes. The iron & steel industry is well aware of these issues; many plants have already taken the first step to energy and decarbonization optimization. A much-discussed approach is to substitute coke or natural gas with hydrogen, preferably produced climate-neutral, for the reduction of iron ore. Despite these process optimizations, the direct emission of CO2 should still be avoided. Chemical absorption by means of amine solution has become established as a commercially proven downstream solution. The absorption process requires a very low content of residual impurities in the off gas, which can be ensured by using advanced gas cleaning technologies. In addition to indirect CO2 reduction, direct heat recovery from the energy-rich process is particularly well suited here for solvent regeneration, whereby surpluses can still be used to cover the company's own electricity consumption and / or compressed air generation. In this context, an overview of the sustainability goals described above is given to focus on the expanded importance of emission control.

Gnauk, Joachim, PSI Metals GmbH, Germany

Co-Author: Jonas Meinke, PSI Metals GmbH • Jan Guhl, Gestalt Robotics GmbH • Robert Piontek, GEFERTEC GmbH

Abstract: The KIKA-IPK project (funded by the German Federal Ministry of Education and Research) aims to provide a cloud platform as a standard for industrial AI applications. This platform will interconnect industry partners and AI third party service providers in such a way that specific problems in production can be analyzed via this platform in a standardized way. The resulting AI application either will be available to the industrial customer remotely or deployed to the on premise system for offline use. The research project aims at developing an AI cognition support system for in-process control, which will enable a more resource efficient process and material configuration through self-learning correlations of signal characteristics with process properties. The machine operator's empirical knowledge of the connection between tangible quality features on the one hand and process characteristics on the other is modelled by machine learning methods. This is demonstrated by the example of additive manufacturing of steel parts.

GonÇalves Andrade, Alexandre, Métal 7 inc., Canada

Co-Author: Alexandre Goncalvez Andrade, Métal 7 inc. • Steve Beaudin, Métal 7 inc. • Gaetan Lavoie, ArcelorMittal Mining Canada

Abstract: The roller screening process plays a crucial role in determining the efficiency of the overall pelletizing operation. The screening efficiency directly impacts the pellet bed permeability in the induration furnace, which in turn affects its performance. The segregation concept is a recent innovation in the industry that has proven to increase productivity and quality of fired pellets, while also reducing energy consumption. The implementation of this concept can lead to significant financial benefits, but also turn out as an efficient way to help pelletizing plants to reduce their carbon footprint. The paper will highlight the principles of these technologies and present its real operational performance compared to a typical screening equipment.

Gordon, Yakov, Hatch Ltd., Canada

Abstract: Minimization of CO2 emissions required changes in reducing gas composition from mixture of CO and H2 to pure H2. Changes in properties of reducing gas leads to changes in process parameters, furnace productivity, consumption numbers and quality of product. Phenomenological analysis of furnace operation was performed to analyze furnace operation with H2 as pure reducing gas. Similarity numbers were evaluated and expected changes in furnace performance were estimated. Influence of lower grade pellets on furnace performance was also analyzed and potential furnace parameters were studied. These findings are used to consult DRI plants on expected changes in DRI furnace performance.

Gordon, Yakov, Hatch Ltd., Canada

Co-Author: Erick Bubniak, DIPROINDUCA   • Jose Senra, Diproinduca Canada Limited • Takshi Sachdeva, Hatch Ltd.

Abstract: To decrease the environmental impact and increase the value of the by-products produced in the steel industry, recycling of by-products is imperative. This paper identifies three technologies as potential solutions to process low-grade feed as well as strategies to decarbonize these technologies. Oxycup process, Tecnored process and SL/RN Xtra are the three technologies being discussed. The raw materials targeted include fines, sludge material and mill scale. Since decarbonization of the steel industry is critical to meet the 2050 goal Sustainable Development Scenario (SDS) of limiting the rise in global temperature to 1.5 ֯C, a transition of these technologies to H¬ydrogen gas or Biomass as a reductant is also looked at. This paper summarizes the raw material specifications, capital cost, operating cost, environmental regulations and preliminary risks for each of the listed technologies.

Gordon, Yakov, Hatch Ltd., Canada

Co-Author: Sunil Kumar, Hatch Ltd.

Abstract: To address climate change the steel industry is increasingly focusing on the reduction of energy consumption as well as Green-House Gas (GHG) emissions. A methodology that incorporates a sound technical element to the assessment of improvement opportunities, was developed to create strategic roadmap for reducing CO2 Emission and Energy Consumption. The methodology is bottom-up, and is applied in much more detail to the specific operations of the iron and steel industry. The methodology was adopted at several operating iron and steel plants (integrated plants and mini-mills) to generate Levelized Cost Curves (LCC) which formed the basis of the strategic roadmaps that were developed. This paper describes the key points of the methodology which helps identify and quantify potential energy savings and CO2 abatement within the iron and steel plants for short term (1-5 years), medium term (5-10 years) and long term (>10 years).

Goryuk, Maksym, National Academy of Sciences of Ukraine, Ukraine

Co-Author: Anastasiia Semenko, National Academy of Sciences of Ukraine • Yuriy Smirnov, National Academy of Sciences of Ukraine • Oleksiy Smirnov, National Academy of Sciences of Ukraine • Sergii Semiriagin, Scientific and Manufacturing Enterprise Dneproenergostal Ltd. • Vadym Osypenko, Scientific and Manufacturing Enterprise Dneproenergostal Ltd.

Abstract: The PTIMA NASU proposed new concept of continuous casting of steel for small metallurgical plants. The idea is both reducing capital costs and amount of equipments. This is achieved by excluding “ladle-furnace” aggregate from technology, reducing number of metal overflows, performing in tundish the finishing liquid steel on temperature & chemical composition, and cleaning from non-metallics. As such multifunctional tundish, it is proposed a pilot magnetodynamic (MD) mixer-batcher for cast iron and steel, developed at the PTIMA NASU. This aggregate uses electromagnetic energy for melt heating, stirring and pouring, and constructively combines functions of induction channel furnace and electromagnetic pump. Such tundish, depending on steel grades produced, process productivity and design of continuous casting machine (CCM), can have one or two chambers, induction channels with inductors, electromagnetic devices for metal stirring and pouring, and also it can be additionally equipped with submersible plasmatron for melt refining. The proposed MD-tundish has following advantages: - adjustable induction heating and electromagnetic stirring of melt; - controlled low-pressure electromagnetic pouring of melt with possibility of distributing and stabilizing flow over the width of CCM mold; - possibility for periodic stop/restart at manufacturing small batches of cast ingots with various sections and from different steel grades; - reduction of metal losses and increasing metal yield; - increasing CCM work stability and productivity; - reduction of refractories’ consumption; - energy saving due to rational modes of melt heating and stirring; - exclusion of using special expensive systems for braking steel flows in CCM mold; - improving quality of cast ingots’ surface due to prevention of their cracking and swelling; - reducing porosity and number of non-metallics; - reducing risk of melt breakthroughs; - improvement of working conditions for personnel and ecology due to use of electrical energy, reduction of thermal radiation and harmful emissions.

Gradinac, Jovana, SMS group, Italy

Co-Author: Nadalutti Andrea, SMS group

Abstract: Water present elementary necessity of life and it may seem inconceivable to imagine living without it. The environmental impact, together with social and economic impact of past and traditional water treatments in steel industry and inevitable fact of water scarcity are leading and driving shift to a new paradigm in a water treatments. Now days, many communities and countries are approaching the limits of their available water supplies and because of that, many steel industry plants are facing a big problem with water availability. Although water reclamation and reuse is practiced in many countries around the world, current levels of reuse constitute a small fraction of the total volume of industrial effluent generated. In addition, to meet their growing water supply needs, communities are considering other non-traditional sources of water which could lead to water saving. Water reclamation and its reuse have become an attractive option for conserving and extending available water supply by potentially applying different solution based on biological, chemical and mechanical improved solutions. Since these trends are emerging developments in the field of water reclamation and reuse, there are a number of research needs associated with these topics. Here proposed research is needed to better understand the issues present in traditional water treatment plants in steel industry, to propose and explain innovative technologies, which are improving traditional solutions of the water treatment plants, and to develop tools and other assistance for the steel industry to implement successful water reclamation and reuse projects.

Gramlich, Alexander, RWTH Aachen University, Germany

Co-Author: Ulrich Krupp, RWTH Aachen University • Frederike Brasche, RWTH Aachen University

Abstract: Press hardening of manganese-boron steels is one of the most efficient production processes for high strength automotive sheet components. However, the energy absorption capacity of these components is greatly limited by the formation of fully martensitic microstructure during in-die quenching. In order to extend the application range of press hardened components, the use of third-generation advanced high strength steels, especially medium manganese steels, achieves increasing attention. The alloying concept of these steels allows the critical cooling rate and the Ac3-temperature to be significantly lowered compared to manganese-boron steels, resulting in a lower austenitizing temperature and shorter cycle times. Aim of the presented research is to analyze the potential of press hardening of lean medium manganese steels with an integrated intercritical annealing or quenching & partitioning treatment. Therefore, different heat treatments were performed on Fe-0.3%C-5%Mn-1.5%Si and Fe-0.2%C-7%Mn-0.2%Si. By adjusting the heat treatment parameters, the microstructure and hence the mechanical properties can be modified to fit the application´s load requirements. The results demonstrate that both treatment strategies lead to complex multi-phase microstructures, which have been analyzed in detail by a combination of EBSD and EPMA. Optimization in heat treatment results not only in high tensile strength, comparable to martensitic 22MnB5, but also in significantly improved total elongation. Regarding the ductility, it was shown that besides the adjustment of a sufficient retained austenite content, the reduction of fresh martensite is indispensable to prevent brittle failure. Finally, selected heat treatments were reproduced in a laboratory-scale press hardening with temperature-controlled hat-shaped pressing tool.

Gramlich, Alexander, RWTH Aachen University, Germany

Co-Author: Hauke Springer, RWTH Aachen University • Ulrich Krupp, RWTH Aachen University

Abstract: The steel industry is a major contributor to global carbon emissions, with the production process being energy-intensive and relying heavily on fossil fuels. It is therefore crucial to find ways to reduce the carbon footprint of the industry in order to mitigate its impact on the environment. One such method is through scrap recycling, where existing steel products are reused instead of producing new steel from raw materials, saving on energy and resources. However, pronounced material integration and multi-material use in technical products lead to a contamination of steel scrap. Some of these contaminations cannot be economically removed during remelting and refining in the electric arc furnace and therefore, a gradual accumulation of detrimental impurities, like Cu or Sn, causes a deterioration of quality. Accordingly, the respective recycling steel grades are not sufficient to fulfil the demanding specifications of flat products, e.g. in the packaging or automotive industry. Strong segregations at the prior austenite grain boundaries leads to the problem of hot shortness, i.e., massive embrittlement of hot-formed steel products. Therefore, a need for the investigation of the influence of elements like Cu on the properties and processability of different steel grades exists and new approaches for tolerating higher Cu concentrations must be developed. The study presents the effects of adding 0.5% and 1.0% copper to reference alloy 42CrMo4 on its transformation behavior and mechanical properties. To investigated the risk of Cu-embrittlement, hot tensile tests were performed. Microstructures are investigated with light optical, scanning electron, and transmission electron microscopy. The results show that copper contamination, which is unavoidable in steel recycling, has the potential to increase the hardness and strength of high strength steels, if it can be controlled during the processing.

Grasselli, Andrea, Tenova S.p.A., Italy

Abstract: C. Leoni1, A. Grasselli1, P. Stagnoli1, B.B. Cheng2, J. Chen2 1 Tenova S.p.A., Italy, 2 Tenova Beijing Branch, China Key Words: EAF, electric arc furnace, Consteel®, energy efficiency, productivity, cost reduction, performance improvement, productivity improvement, revamping. Abstract The ever-changing steel industry requires thinking of production plants that can guarantee the flexibility and sustainability needed to compete in the steel market. The success that the Tenova Consteel® EAF system has earned over the years is proof of a winning approach to the steelmakers' demands. Continuous technological development leads to design increasingly high-performance and productive furnaces, being able to choose smaller heat sizes even for significant annual steel throughput. This opportunity makes it possible to reduce the overall investment costs of a new production site, linked proportionally to heat size, or to think about revamping existing plants that need ambitious productivity increases. The paper presents the results of a Tenova's reference plant in China: two 70 tons heat size Consteel® EAFs for the production of more than 2 million tonnes of carbon steel per year, to which will be added the third production line with the same characteristics now under commissioning.

Grasselli, Andrea, Tenova S.p.A., Italy

Co-Author: Davide Masoero, Tenova S.p.A. • Naci Faydasıçok, Hasçelik Sanayi ve Ticaret A.Ş.

Abstract: Key Words: EAF, electric arc furnace, Consteel®, Consteerrer®, ArcSave®, EMS, energy efficiency, productivity, cost reduction, performance improvement, quality steel, productivity improvement, revamping. Abstract The constant evolution of the steel industry emphasizes how sustainability and flexibility are strategic parameters of increasing importance in the production process of steel. Tenova, in cooperation with its partner ABB, has made available to the market the Consteerrer®, an innovative ArcSave®-based electromagnetic stirring technology jointly developed by ABB and Tenova for continuously charging EAF systems. The paper presents the main features of the technology that Hasçelik selected for its first electric furnace as the optimal solution to successfully meet the challenges of the Turkish market in which the plant will operate. Consteel® EAF combined with Consteerrer® helps producing high quality steel as well as significantly reducing the production cost, ensuring high flexibility in terms of both material charge and finished product. The solution chosen by Hasçelik will be the first continuously charged EAF in Turkey and will give the opportunity to leverage the inherent flexibility of the Consteel® EAF to tackle the declining scrap availability and quality as the continuous charge makes the process intrinsically robust to the variation of the scrap density, quality and content of volatile compounds. The combination with an optimized application of the Consteerrer® EMS reduces the thermal process losses, increases the melting speed, homogenizes the liquid steel and reduces the oxygen content of the bath.

Griessacher, Thomas, Stahl- und Walzwerk Marienhütte GmbH, Austria

Co-Author: Daniel Ott, Primetals Technologies Austria • Helmut Hlobil, Primetals Technologies Austria • Oliver Lang, Primetals Technologies Austria

Abstract: For more than one and a half years ShapeMon Billet Bloom is installed now at Stahl- und Walzwerk Marienhütte GmbH in Graz. The system inspects their two lines of billet production. While the starting focus was on reliable length measurement and weight calculation, the modular design of the system with laser line projection, and cameras for evaluation of laser line and surface, shows more and more tasks, that can be fulfilled by the measurement device. With the high data acquisition frequency strand jerking is detected by the system and a warning is generated in case of excessive jerking. It indicated that the mold taper does not fit to main parameters like casting speed, oil or powder used for lubrication. At best the jerking detection can help to prevent sticker breakouts. The second use case for quality inspection via data analysis of the system, is the detection of surface cracks. With image analysis it is possible to detect longitudinal as well as transverse cracks, classified into two categories. Severe ones that may cause breakouts while being straightened and smaller ones that reduce the quality of billets and may create problems in the rolling process. Also, when cracks are detected, alarms are generated to inform operators and assist them in deciding on appropriate actions such as adjusting casting speed, water flows, etc. Marienhütte was able to reduce breakout rates by approximately 80% and transverse crack surface defects close to zero with this system installed at the billet caster.

Griesser, Stefan, qoncept technology GmbH, Austria

Co-Author: Robert Pierer, qoncept dx GmbH • Sebastian Michelic, qoncept dx GmbH

Abstract: Steelmakers across the globe are increasingly facing a decarbonization challenge. Recent developments in raw material and energy cost, supply chain volatility and CO2 regulations have put a lot of pressure on steelmakers which underlines the need for highly efficient and sustainable production processes. The switch to electric and hydrogen-based steelmaking in Europe brings additional challenges and requires the use of new raw materials (such as DRI), operation practices and adapted secondary metallurgical processes. This is partly a journey into the unknown and must be carefully navigated for successful implementation. The present paper presents a new digital solution for the optimization of existing electrical steelmaking processes and to answer the following questions: - How will new raw materials change my processes? - How can I predict the behaviour of new metallurgical processes? - How can I adapt to new equipment and technology? - How to define new operating practices? Metallurgical intelligence, cross-process optimization and sophisticated mathematical algorithms are at the core of this new application, which allows substantial cost savings, optimized production as well as reduced CO2 emissions. The influence of varying scrap composition, different types and amount of DRI, melting strategy, secondary metallurgical treatment and alloying strategies can be analysed and optimized in real-time. The presentation provides various practical examples, and the resulting cost and CO2 reduction is discussed.

Gruber, Christine, K1-MET GmbH, Austria

Co-Author: Maria Thumfart, K1-MET GmbH • Johannes Wachlmayr, K1-MET GmbH • Roman Rössler, voestalpine Stahl GmbH • Birgit Palm, VDEh-Betriebsforschungsinstitut GmbH • Bernd Kleimt, VDEh-Betriebsforschungsinstitut GmbH • Sudhanshu Kuthe, KTH Royal Institute of Technology • Björn Glaser, KTH Royal Institute of Technology • Izaskun Alonso Oña, Sidenor Investigación y Desarrollo • Vito Logar, University of Ljubljana • Dejan Gradisar, Institute Jozef Stefan • Miha Glavan, Institute Jozef Stefan • Mojca Loncnar, SIJ Acroni d.o.o. • Pavel Ettler, Compureg Plzeň S.r.o. • Matjaz Demsar, Siemens Trgovsko in storitveno podjetje, d.o.o. • Zdravko Smolej, SIJ Acroni d.o.o.

Abstract: The INEVITABLE project applies digital technologies for an optimized and improved performance of different metalmaking processes with focus on steelmaking but also for nonferrous alloy casting. The aim is the development of high-level supervisory and control systems for different production plants and their demonstration in operational environments to enable an optimized operation of the processes, going hand in hand with a reduction of resource consumption and CO2 emissions. The digital transformation and upgrade of the processes include data acquisition, processing and analytics of datastreams, standardization of relevant data interfaces and storage, and application of the functionalities of smart sensor technologies, cognitive control and Industry 4.0 concepts. The INEVITABLE project revolved around various steelmaking processes, ranging from electric arc furnace (EAF) and secondary metallurgy up to the cold rolling mill. This talk gives an overview over the cognitive control solutions developed in the project. For the EAF operations, process models and optimization framework have been developed, based on both theoretical and data-driven approaches using operational data. Their aim is to allow continuous online estimation of the bath temperature and oxygen level, offline process simulation for scenario testing, and optimization of the energy consumption via improved EAF inputs. In secondary metallurgy, ladle furnace and vacuum degassing processes have been considered. Based on vibration sensors and image data, the stirring behavior has been monitored. Together with the evaluation of other process data, model-based advisory systems for process control and decision support as well as predictive models for cleanliness and castability of liquid steel have been developed. Furthermore, a system for supervision, optimisation, and condition monitoring of cold rolling mills has been developed. Strip speed sensors and an x-ray thickness measurement have been introduced, and an overall upgrade of the databases has been implemented, including communication interfaces between sensors, edge devices and cloud database.

Grundy, A .Nicholas , Thermo-Calc Software AB, Sweden

Co-Author: Lina Kjellkvist, Thermo-Calc Software AB • Ralf Rettig, Thermo-Calc Software AB

Abstract: There is currently a distinct trend in AI / ML type simulations of the steelmaking and -refining process. Such approaches can very accurately predict the outcome of steel processing, however there are 2 major drawbacks: 1) They only work well in the limits, within which the algorithms have been trained. 2) They are largely a black-box approach, where cause and effect remain hidden. The alternative approach are physical models, that are based on general principles like conservation of mass, conservation of energy, etc… that hold true far outside the narrow window, inside which steel processing is mostly constrained. This means predictions can be made on what happens when the process leaves this window. While such an event might be rare in a well-controlled industrial environment, it is crucial to know what happens, as the potential damage caused if appropriate action is not taken, can be massive. A further advantage of physical models is that the influence of distinct steps in the processing can be analysed separately, as they need to be explicitly implemented in the physical model. Finally -unlike an AI / ML model, a physical model will also provide information for properties for which no experimental measurements have ever been performed. In this paper, a physical model for steelmaking and -refining is presented, that uses thermodynamic equilibria calculated with Thermo-Calc and the CALPHAD type steel and slag database TCOX12. Reaction kinetics are accounted for using the Effective Equilibrium Reaction Zone (EERZ) model. The model is commercially available as the Process Metallurgy Module within the Thermo-Calc Software package and already being used in academic and commercial research. Some application examples are given and if it shown how simulations can be run, directly using process data stored in a Level 2 system.

Gulda, Maria Persson, Chief Technology Officer, H2 Green Steel, Sweden

Abstract: H2 Green Steel was launched February 2021 with the ambition to decarbonize hard-to-abate industries, starting with steel. By 2025 we will have production up and running, in Boden, Sweden, scaling volumes in 2026 to 2,5 million tonnes of steel. In phase two of our project, we will produce 5 million tonnes of steel per year. Our production site in northern Sweden, will hold one of the world’s largest electrolysis plants for green hydrogen production to date, a DRI tower for the production of sponge iron and an ultra-modern steel mill to produce the green steel. The renewable electricity locally sourced in northern Sweden is key to making this happen. Our founder and largest investor is Vargas, which is also co-founder of Swedish battery maker Northvolt and several other green impact companies. Over the course of the past two years since launch, we have obtained our permissibility permit, started construction in Boden and on top of a €86 million series A financing, we closed our series B equity round at €260 million October last year. In addition, leading financial institutions, including major commercial banks and the European Investment Bank, have announced their intention to back our debt funding with €3,5 billion. We have presold about 60% of our initial volumes to customers like BMW, Mercedes, Miele, Electrolux, Scania, Adient, Schaeffler and Kingspan who have validated the demand for green steel. We are also looking into prospects on the Iberian peninsula, in Brazil and locations in North America that have the special prerequisites in terms of land and access to renewable electricity production.

Günerdi, Murat, Çolakoglu Metalurji A.S., Turkey

Co-Author: Andreas Fischer, Primetals Technologies Germany • Talip Kücük, Çolakoğlu Metalurji A.Ş. • Burhan Gündogan, Çolakoğlu Metalurji A.Ş. • Dincer Demircioglu, Çolakoğlu Metalurji A.Ş. • Naci Arun, Primetals Technologies Germany • Zafer Cetin, Primetals Technologies Germany

Abstract: "As the request for ultra low carbon (ULC) steel and stainless steel is rising in the Turkish market, Colakoglu Metalurji A.S decided to increase the production capability for mentioned steel grades. Accordingly, the 300 tons capacity vacuum degassing (VD) plant was modernized by Primetals Technologies in 2020. In this paper, the modernization of the VD plant to the world's largest capacity vacuum oxygen degassing (VOD) plant will be explained. The 304L stainless steel production process and encountered problems with new equipment commissioned, updates of the automation and the level 2 systems will be described. As a result of this modernization work, the production of 304L was performed successfully in the VOD plant. The highest stainless steel heat size with 294 tons and the lowest Carbon level of 5 ppm in the world were achieved with the developed metallurgical patterns during the commissioning of VOD plant."

Günther, Peer Eric, Hüttenwerke Krupp Mannesmann GmbH, Germany

Co-Author: Thomas Sturz, Hüttenwerke Krupp Mannesmann GmbH

Abstract: Within the steel industry it is commonly known that slopping of slag and molten steel occurs in the BOF. Whilst searching for the reasons of slopping is still part of much research, it is also of interest how to manage these events of slopping and how to predict them as slopping events are problematic for environmental reasons and costly in their removal. Within the steel mill of Hüttenwerke Krupp Mannesmann GmbH (HKM) a technology for prediction of slopping is developed using acoustical analysis. The implementation of this technology is described, as well as the results to predict and to prevent excessive slopping of the converter vessel.

Gupta, Durgesh, H2 Green Steel, Sweden

Co-Author: Anatoliy Meyko, Midrex Technologies, Inc. • Marco Perato, Paul Wurth Italia S.p.A.

Abstract: H2 Green Steel is on a mission to decarbonize hard-to-abate industries, and the steel industry is a prime place to start. Steel production is the source of 7-9% of global CO2 emission, 5% of CO2 output in the European Union, and 14% of CO2 generated in Sweden, the home country of H2GS AB. Sweden possesses an abundance of natural resources necessary to support green steel production via the direct reduction-electric arc furnace route (DR-EAF). H2 Green Steel is bringing together the technology expertise of Midrex in processing iron ore into steel products, creating green hydrogen with giga-scale electrolysis, and developing a circular supply chain to become the first commercial-scale supplier of green steel by 2025. The story of how H2 Green Steel decided to undertake a steel project in northern Sweden – 45 mile south of the Arctic Circle, development of the technical scope of the project, and what will be involved in the steel mill reaching its design capacity of 5 million metric tons/year is the focus of our presentation. We will discuss the further steel-related plans of H2 Green Steel and how the Boden project will provide the technical blueprint for future green steel projects.

Gurrath, Karola, Primetals Technologies Germany, Germany

Co-Author: Matthias Kurz, Primetals Technologies Germany • Raphael Twardowski, thyssenkrupp Steel Europe AG • Klaus Loehe, Primetals Technologies Germany • Andrea Schmidt, Primetals Technologies Germany

Abstract: By upgrading individual software components, steelmakers can continuously modernise their plants and achieve more sustainable quality production. An example of this is thyssenkrupp's recent upgrade of an advanced profile, flatness and contour control system into an existing third-party automation system. The new configuration consists of a level 2 set-up system and a level 1 real-time controller. In addition to fundamental quality improvements, the focus is on flatness guarantees, which are increasingly in demand from end customers. This article describes the virtualised system, the analysis tools and the digital twin in detail. Results are also shared, including the improvements to strip quality and the reduction in the number of further downstream processing steps required to achieve the desired product quality.

Gusarova, Tamara , SMS group, Germany

Co-Author: Stephan Six, SMS group • Arnoud Kamperman, Tata Steel IJmuiden B.V. • Roy Frinking, Tata Steel IJmuiden B.V.

Abstract: Complaints from end-customers cost more than recycling of defect material produced. Therefore it is important to be sure about the quality of the cast steel material prior selling. Internal quality of cast material can be proved via etching / sulfur print or with the new ultrasound technique developed by SMS group GmbH under the name HD scan. The first industrial HD scan system was installed by Tata Steel IJmuiden in December 2018. Since then Tata Steel and SMS work in close cooperation for further optimization of quality evaluation. Several hundreds of samples were measured in production process, more than a hundred were additionally etched and results compared. In consequence, similarities and differences between etching and ultrasound methods were discussed. Most of the results match, however for some samples (normally steel grade specific) discrepancies were observed. Whereas by etching only one surface layer is analyzed, HD scan provides higher reliability of defect distribution due to volume information. Moreover, sometimes defects like cracks are smashed and hidden by sample preparation prior etching. For some other samples differences in results is a case for further studies. The key question to be considered is – what is the best technique for cast steel quality evaluation in modern digital world? Various measurement results from Tata Steel IJmuiden sample will be presented and discussed, as well as some information from other HD scan customers will be given.

Haase, Rico, Fraunhofer Institute for Machine Tools and Forming Technology, Germany

Co-Author: Matthias Nestler, Fraunhofer Institute for Machine Tools and Forming Technology • Julia Schönherr, Fraunhofer Institute for Machine Tools and Forming Technology • Verena Kräusel, Fraunhofer Institute for Machine Tools and Forming Technology

Abstract: By press hardening of boron-manganese-alloyed steels, extraordinary strength can be achieved. Accordingly, the process is applied for different crash relevant components in the car body structure. Aiming for an outstanding energy dissipation, sections with lower ultimate strength to the benefit of an increased elongation are required. This can be achieved by a tailored tempering process, where the uniform heating and segmented cooling figured out to be the most appropriate process route on an industrial scale. Due to the non-uniform distribution of temperature during the quenching phase and the uneven level of thermal strains in the final cooling subsequent to the forming itself, a higher level of distortion was observed. Thus, a detailed understanding of the thermal effects and flux during the whole process chain is a key condition in order to achieve stable mechanical as well as geometrical properties. Within the recent research project gratefully supported by FOSTA, this detailed analysis of the thermal evolution of the different part sections of a tailor-tempered part were elaborated. By the repetitive crosscheck between process-integrated measurement and FEA prediction, the microstructural evolution and geometric accuracy were investigated. The relation between elastic spring back, thermal shrinkage and their interaction towards parts stress state and geometric deflection was examined. By the more detailed understanding of the underlying mechanisms, the route is opened for well-aimed compensation strategies. While the portion of press-hardened and in particular tailor-tempered components is established and stable in the car body structure, the ongoing development towards large-sized BIW-components such as the door ring concept come into the competition. This amplifies the relevance of the component accuracy and thus of the presented topic.

Hackl, Gernot, RHI Magnesita GmbH, Austria

Co-Author: Gerald Nitzl, RHI Magnesita GmbH • Wolfgang Fellner, RHI Magnesita GmbH

Abstract: The quality of continuously cast steel is greatly influenced by the flow conditions in the mould, particularly at the meniscus, where the liquid steel is in direct contact with the casting flux. Stable conditions within a defined velocity range need to be achieved to avoid slag entrainment, one of the causes for product defects such as slivers on cold rolled sheets or defects on heavy plates, as well as an increasing breakout risk, due to uneven mould lubrication. Determination of the flow inside the mould therefore is an important aspect in order to assess the status of the system and derive possible measures for improvement, such as by the design of submerged entry nozzles. This paper presents the application of a method to continuously measure the sub meniscus velocity in the mould of slab casters using immersed paddles. Information about the velocity distribution as well as the general flow pattern trend and stability can be gathered. This goes beyond standard nail dipping tests, which typically only provide a snapshot but lack information about transient phenomena. In combination with modern simulation technology the described system can support general design optimization of refractory solutions for the continuous casting process and in particular provide criteria for tailor made customer solutions. Several examples are shown in this paper.

Haimi, Timo, Metso Outotec Oy, Finland

Abstract: Case study: Three different feeds to a DRI smelting furnace Timo Haimi, Metso Outotec Metals Oy Abstract The decarbonization of Iron and Steel Industry has been progressing rapidly in the recent years with many projects advancing into next stages. The standard solution for lower CO2 emissions in steel making has been using the shaft kiln based direct reduction plant and a scrap melting electric arc furnace instead of blast furnace. However, if the majority of the primary steel making plants would follow the same approach, there would be a shortage of DRI-quality iron ore and high quality steel scrap. Hence there is a need to utilize new technological solutions to enable use of standard, blast furnace grade iron ore, especially to deal with the excess gangue and higher amount of slag. Metso Outotec has been checking whether the existing non-ferrous and ferroalloys smelting furnaces could be used in smelting of direct reduced iron feed, with the target of removing the slag from the DRI feed without causing extra iron losses into the slag. As there are many different types and qualities of DRI available for the smelting feed, there is also a need to evaluate the differences of each feed and all different DRI types would naturally generate different type of metal product as well. The following paper describes three case studies about different DRI feeds into the Metso Outotec DRI smelting furnace. The first case is high quality DRI with 0% carbon content, the second case is BF-grade DRI with 0% carbon content and the third case is BF-grade DRI with 4% carbon content. The carbon contents of these product metals made out of these feeds have been assumed to be 1%, 2% and 4% respectively. The case studies are showing different process parameters for each cases

Hain, Simon, Primetals Technologies Germany, Germany

Co-Author: Andreas Maierhofer, Primetals Technologies Germany

Abstract: "Silicon steel grade sheets are essential to e-mobility. The material is hard, thin, and brittle, especially at the edges. With thinner gauges, magnetic losses are reduced, but the filling factor increases with more sheets. Therefore, the permeability and magnetization diminish. Contactless flatness measurement is beneficial for reducing the risk of strip breaks from edge cracks and to control flatness also at lower rolling speed. Additionally, it helps to get faster into the tolerances at the strip head since the response time due to the measuring principle is constant. Compared with flatness rolls which have to turn to get measurement readings the contactless principle allows to measure independently from a rotating roll or strip movement. Primetals Technologies has developed contactless flatness measurement consisting of actuators to oscillate the strip and eddy current sensors to detect inhomogeneities of the internal tensions. Since there is no contact with the strip, surface quality is maintained, and no wear occurs. Because of the straight forward construction, compared to a flatness roll, a maintenance can be done on site by the service personal in short time."

Hallmanns, Nils, VDEh-Betriebsforschungsinstitut GmbH, Germany

Co-Author: Roger Lathe, VDEh-Betriebsforschungsinstitut GmbH • Andreas Wolff, VDEh-Betriebsforschungsinstitut GmbH • Detlef Sonnenschein, VDEh-Betriebsforschungsinstitut GmbH • Hagen Krambeer, VDEh-Betriebsforschungsinstitut GmbH • Monika Feldges, VDEh-Betriebsforschungsinstitut GmbH • Alexander Dunavitzer, VDEh-Betriebsforschungsinstitut GmbH

Abstract: In flat steel production, flatness of steel strips and plates is of paramount significance for a safe and stable process operation and essentially defines final product quality. Although local flatness is controlled successfully during rolling, many steel plants face significant flatness problems for thin and/or high-strength steel products in downstream processes and after production. Especially the automotive industry has increasing demands for thinner and higher-strength steels. But this implies new difficult challenges for the aged plants and machinery run at their physical and technical limits to produce such highly specialized steel products. Additional limits are given in terms of cooling capacity, maximum required strip tension or the required rolling force, but most importantly by roll bending and continuous variable crown. HatFlat investigates cross-process influences on the development of flatness defects. For this purpose it will apply a unique way of combining existing models based on physical laws – so called first-principle models – and state of the art machine learning (ML) approaches. This so-called physics-informed ML approach allows to a) improve the prediction of flatness and flatness deficiencies, b) identify the influential factors of greatest impact on flatness and c) to make proposals for changing the processes (as long as the product quality specifications are not affected) for achieving a better flatness characteristic. The project will also utilize proven Industry 4.0 tools, such as digital product twins for hosting the prediction models. The models developed in HatFlat will be assembled into a holistic assistance tool for flatness prediction. Featuring a strong industrial participation of some of Europe´s biggest steel producing companies, plants allocated along the process chain of steel processing with strip and plate products, two highly reputed steel research institutes and a university, all working together to create one new tool for predicting, understanding and improving flatness.

Hansmann, Thomas, SMS group GmbH , Germany

Abstract: Steel is the backbone of the future low-carbon society. As the demand for steel is set to increase for several reasons such as steel intensity of renewable energy infrastructure and further developments of emerging markets, steel is also unique in its ability to be almost infinitely recyclable. In addition, steel can plot credible technological pathways for significant reductions in greenhouse gas emissions. However, the decarbonization of the iron and steel industry faces very different regional challenges. Among the others, clear incentives lead to decisive action in Europe, with pathways mainly based on direct reduction followed by various types of electric (s)melting. The transition towards green steel though is not limited to the European steel industry but has become a global priority. In different regions of the world we are facing various initiatives to convert existing steel plants into low carbon steel production, our experience reaches from greenfield fully hydrogen based steel production up to innovative solutions for existing integrated facilities. As a global player, the SMS group faces indeed the challenge of serving these diverse conditions. Thanks to 150 years of experience we have developed a deep understanding of all the technologies and processes. Continuously searching for innovative products and methods we have made our mission to create a carbon neutral metal industry.

Harp, Guenter, Harp Process Chemistry Consulting, Germany

Abstract: The use of green H2 as reductant shall lead to a CO2 lean ironmaking. The industrial demand of green H2 in the future cannot be supplied via own resources and must therefore be imported from regions with better prerequisites for green H2 as well as renewable electricity production e.g. MENA region. The problem to transport such big amounts of green H2 shall be solved by using liquid ammonia (NH3) as H2-carrier. One missing link in this H2 transportation chain is the availability of an industrial proven solution for the NH3-splitting to recover the H2. This is still under development. Using green methanol (MeOH) as H2 carrier does not have this problem, because industrial proven solutions exist for all parts of the H2 transportation chain as well as the chain closing the CO2 cycle related to green MeOH production and its use. Moreover 1 m³ of MeOH lead stoichiometrically to 148 kg of H2, whereas 1 m³ liquid NH3 lead stoichiometrically to 107 kg of H2. Besides that, MeOH is an interesting reductant for iron oxides due to its physical and chemical properties. Under normal conditions it is a liquid. Its boiling temperature is 65°C, which makes it applicable to vaporize with low temperature waste heat. Methanol vapor is chemically adsorbed on the surface of hematitic as well as magnetitic iron oxides. At about 320°C it causes a reduction to ferrous oxide FeO, H2 and CO2 as reaction products leading to a new concept for DRI production.

Haschke, Arno, Primetals Technologies Germany, Germany

Co-Author: Andreas Maierhofer, Primetals Technologies Germany • Sebastian Kündinger, Primetals Technologies Germany

Abstract: "Over the last few years, several promising products on the market have been offering artificial intelligence or predictive maintenance to overcome the difficulties of monitoring the condition of assets in a plant. The key to creating the methods and analysis, which allow for reliable monitoring, rests in an understanding and knowledge of the process and technology of a production line. Reliable monitoring is accomplished using state-of-the-art methods, e.g., data analytics, for analyzing and creating suitable responses to operating conditions and disturbances. Primetals Technologies has developed a digital assistant that uses the understandings mentioned above to monitor any assets in any plant. Additionally, it can integrate existing monitoring systems, adapt to various data sources, or combine different analysis results to solve more complex monitoring demands in one central system. Besides reliable and automatically monitoring 24/7/365, the new system delivers solution-oriented information, which helps operators make the right decision and act fast in case of an alert. It provides this additional information based on built-in know-how to make anticipating and overcoming potential malfunctions easier."

Haschke, Thomas , SMS group, Germany

Co-Author: Thorsten Huge, SMS group • Michael Lipowski, SMS group • Christian Mengel, SMS group • Bettina Fischer, IMS Messsysteme GmbH • Horst Krauthäuser, IMS Messsysteme GmbH • Ingo Leckel, Salzgitter Flachstahl GmbH

Abstract: An excellent width performance is indispensable to enable stable, efficient and sustainable production. Since width control in hot rolling mills is almost exclusively possible in the roughing mill, the width measurement in the roughing mill is of particular importance. Radar technology has proven to be suitable for such applications due to its robustness and precision even under the harsh environmental conditions including steam, dust and high temperatures. In the hot strip mill in Salzgitter, a radar width measurement is installed between the slab sizing press and the roughing mill immediately upstream to the edger and used for several tasks in order to optimize the transfer bar and therewith finally the finishing strip width: First, the width error coming from the slab sizing press is calculated by comparing the slab width measured in the radar gauge and the setup width of the press. A possible width error is corrected by an adaption model in the pass schedule model PSC® and given as an additional offset to the slab sizing press for the subsequent slab. Second, the measured strip width is considered in the PSC® within the recalculations of the reversing passes in the roughing mill. Based on the reliable measurements, updated width information are used to calculate new setups for the next subsequent combinations of width- and thickness-reductions in the roughing mill. Third, the information from the radar gauge are used in the level 1 control system for plausibility checks in order to optimize the tracking accuracy and therewith the short stroke control at the slab ends in the edger. With these measures, the width errors and above all the excess width at the strip end could be significantly reduced. Further improvements can be achieved by considering the measurements in the short stroke control to avoid necking respectively excess widths.

Hauck, Thorsten, VDEh-Betriebsforschungsinstitut GmbH, Germany

Co-Author: Jean Borlée, Centre de Recherches Metallurgiques • Tobias Kempken, VDEh-Betriebsforschungsinstitut GmbH

Abstract: To achieve the set EU climate strategies & targets the European steel industry is in an extensive transformation process towards climate-neutral steelmaking. Over the last years promising technology pathways were developed and steel producers created specific roadmaps for their implementation. The implementation along these roadmaps lead to decarbonisation scenarios for the European steel industry. This process is highly dependent on relevant external framework conditions. In the RFCS project “Green Steel for Europe” (grant agreement number 882151) relevant framework conditions were identified and seven decarbonisation scenarios were developed. So called external framework conditions include the availability of green electricity and hydrogen, natural gas, alternative carbon sources, CO2 storage locations, iron ore & pellets, steel scrap and the demand for CCU products. Additionally, framework conditions such as the industrial maturity of technologies, investment cycles, financial and legislative conditions were taken into consideration. Three scenarios for 2030 show how the set climate target can be achieved and what influence a delayed implementation or increased hydrogen availabilities can have. Four scenarios for 2050 display the road towards carbon-neutral steelmaking with or without further breakthrough technologies and dependent on scrap availability. For these scenarios the implementation of four dedicated technology routes for primary steel production was investigated: optimized operation of the conventional route via blast furnace and basic oxygen furnace, direct reduction based on natural gas and/or hydrogen, smelting reduction and iron ore electrolysis. The project concluded in 2021, thus before the Russian war on Ukraine and its consequences for European framework conditions. This paper gives an update on the changed framework conditions, revised roadmaps and resulting decarbonisation scenarios. The transformation process of the European steel industry will result in a heterogeneous situation in the next decades with hydrogen-based direct reduction and electrification playing major roles.

Haverkamp, Mark , SMS group, Germany

Co-Author: Sebastian Kemper, SMS group • Thomas Nerzak, SMS group • Andre Peschen, SMS group • Karsten Weiss, SMS group

Abstract: Digitalization is currently the focus of the steel industry in order to optimize plant planning, production, maintenance, service and training. Due to the large system dimensions and according complexity, intelligent solutions are in demand today more than ever. The "XR Plant Inspector" (XRPI) is such a solution. It was developed by SMS group to visualize complex plant models in 3D. In contrast to conventional CAD programs, this software can display entire steelworks in full detail by techniques deduced from the game world. XRPI creates a digital image of the real system, which e.g. helps to analyze maintenance tasks quickly and effectively. During training, XRPI supports participants in surveying the complete system virtually and collaboratively, thereby significantly enhancing qualification. Through this immersive training, the customer gains an immediate deep insight and can identify directly with his system, even in an early planning stage. Furthermore, the XRPI facilitates the commissioning process. Here, open questions, changed boundary conditions and solution approaches can be documented and discussed through the direct connection to the 3D data, preventing miscommunication. But that's not all, the software has recently been expanded to include important additional features, in particular the link to other SMS plant apps, providing an coherent overall concept to the customer. The XRPI new developments include e.g. the automated 3D model creation, the integration of 3D animations, an interface to eDoc (direct link to technical plant documentation) as well as an open MQTT interface, which enables the connection to other SMS apps such as Genius CM (predictive maintenance app). The publication describes these new developments. The use cases listed here give an insight into the wide range of potential applications and advantages for the plant operator.

He, Franz, Friedrich-Alexander-Universität Erlangen-Nürnberg, Germany

Co-Author: Marion Merklein, Fraunhofer Institute for Manufacturing Technology and Advanced Materials

Abstract: Energy conservation and overall vehicle efficiency has been steadily gaining importance in the automotive sector over the years, especially with the technological switch to electrically powered vehicles. Lightweight parts are therefore required to provide safety relevant components with reduced part weight for the automobile while at the same time not compromising in aspects of passenger security. Hot stamping has proven itself to be a suitable process for the generation of automotive components, which meet the contrary requirements by improving mechanical properties and thereby passenger safety while at the same time providing lowered part weight through reduced sheet thickness. Due to increased forming temperatures above 850 °C, the usage of lubricants is not yet viable for hot stamping. To prevent decarburization and scale formation an additional aluminium-silicon based coating is applied to the boron manganese base material. The lack of lubricant usage combined with the coating material results in occurrences of high friction and wear at high temperatures. Previous investigations have shown that process parameters exhibit a significant influence on friction and wear in the process. Furthermore, the workpiece sided austenitization parameters as well as coating thickness have proven to influence the layer formation in the coating layer. Within this study the influence of the initial coating thickness on the friction and wear behaviour as well as interdependencies with other significant parameters is investigated. To this end, strip drawing tests are performed with both coating strengths and analysed in regard to the resulting tribological behaviour. The results of this study help in improving the understanding of the tribological conditions within the hot stamping process and to develop tailored measures for reducing tool and part wear.

Heidari, Aidin, University of Oulu, Finland

Co-Author: Timo Fabritius, University of Oulu • Mikko Iljana, University of Oulu

Abstract: The study aimed to compare the reduction behavior of DRI (direct reduced iron) and blast furnace pellets in a CO-H2 atmosphere. The experiments were conducted under controlled conditions to evaluate the effect of temperature and CO-H2 ratio on the reduction process. The reduction rate and final degree of reduction were used as the main parameters to compare the performance of DRI and blast furnace pellets. The results showed that the reduction rate of DRI was much faster than that of blast furnace pellets, and the final degree of reduction was also higher for DRI. This can be attributed to the higher reactivity and porosity of DRI, which facilitates the transfer of gaseous reduction agents and results in a more complete reduction process. The study also found that increasing the temperature and CO-H2 ratio improved the reduction rate for both DRI and blast furnace pellets. However, DRI still showed better reduction performance compared to blast furnace pellets under all experimental conditions. The comparison of the reduction behavior of DRI and blast furnace pellets in a CO-H2 atmosphere highlights the advantages of using DRI as a raw material in the iron and steel industry. The results of this study demonstrate that DRI is a more favorable alternative to blast furnace pellets in the CO-H2 reduction process due to its higher reactivity, porosity, and reduction rate. The findings of this study can help optimize the reduction process and improve efficiency and could have important implications for the iron and steel industry, particularly for the production of high-quality steel products.

Henrich, Falk-Florian, Smart Steel Technologies GmbH, Germany

Co-Author: Lucas Corts, Smart Steel Technologies GmbH

Abstract: Conventional scheduling methods utilized in the steel production process, primarily semi-manual in their nature, tend to result in operational challenges. They are characterized by a lack of accurate and reliable quality prediction capabilities and cannot cope with the complexity of dynamic synchronization of upstream and downstream operations. An insufficient level of automation and a limited planning horizon present challenges in effectively harmonizing the planning of melt shop, casting and rolling operations. As a result, the direct and hot charging rates of an integrated steel plant are often low, leading to suboptimal energy utilization and high inventory and slab handling costs. To overcome these challenges, advanced scheduling systems that employ a combination of automation and reliable quality prediction have been developed. These systems can adjust dynamically in real-time to mitigate upstream deviations, which leads to increased hot charging rates and improved energy efficiency. By using automated scheduling, high utilization and coordination of equipment across all process stages can be accomplished. Smart Steel Technologies will elaborate on how an advanced scheduler utilizes mixed integer solvers and artificial intelligence models to optimize the scheduling process. Intelligent cost functions take into account quality predictions and all influencing restrictions from relevant aggregates. As a result, precise scheduling that boosts productivity and lowers energy consumption in difficult market conditions can be achieved.

Hessling, Oscar, Swerim AB, Sweden

Co-Author: Du Sichen, Hybrit Development AB • Niklas Kojola, Hybrit Development AB • Julia Brännberg Fogelström, Swerim AB • Johan Martinsson, Swerim AB

Abstract: Hydrogen reduction of iron ore, to reduce carbon emissions in the steel industry, is a plausible way forward as focus on fossil free production increase. The CO2 byproduct, generated by carbon reduction, is negated and replaced with H2O. In a Hydrogen Direct Reduction shaft, both temperature and pH2O will vary over the shaft height. Lower temperature and higher pH2O found at the top. The reduction reaction with hydrogen is highly dependent on the temperature and pH2/pH2O ratio. Lower temperature and higher pH2O would result in a lower reduction rate. Since only a few systematic studies have been conducted, this work aims to study the effect of pH2O over a temperature range relevant to industrial practice. A resistance heated furnace and a water vapor generator is employed to investigate the 0-15% pH2O range, in the 600 °C – 900 °C temperature range. To produce reliable data, the water content in the gas must be accurately controlled. A system is carefully designed to ensure precise control of the water content in the reaction gas. To further the industrial context, industrially produced iron ore pellets are utilized. Thermal Gravimetric Analysis (TGA) is used to follow the reduction. To understand the reaction mechanisms, SEM is used to study the microstructure of partially reduced pellets. Results suggest the reduction rate is profoundly affected by water at low temperatures, less so when the temperature is increased. The microstructure is highly affected by pH2O at 600 °C, at higher temperatures the microstructure is largely unaffected. Reaction mechanisms are discussed based on the reduction curves and micrographs. The impacts of gas dilution and chemical reaction rate are evaluated.

Higashi, Ryota, Tohoku University, Japan

Co-Author: Daisuke Maruoka, Tohoku University • Taichi Murakami, Tohoku University • Eiki Kasai, Tohoku University • Yuji Iwami, JFE Steel Corporation

Abstract: The iron making industry consumes a large amount of fossil fuel derived carbon as heat source, reducing agent of iron ores and carburizing agent of reduced iron. Carbon is an essential element for an efficient ironmaking, although hydrogen is expected to be the substitution. The carbon recycling ironmaking process by circulating CO gas has been already proposed to achieve carbon neutrality. However, the production of hot metal is not considered in this process because CO gas is not utilized as a carburizing agent. In order to apply the carbon recycling ironmaking process to the production of the hot metal, new ironmaking process of carbon solidification using porous iron whisker and production of hot metal using recovered carbon-iron ore composite is proposed in this study. The lumps of iron whisker with high porosity, approximately 95% were obtained by heating the mixture of fine hematite reagent and biomass char at 950℃ for 75 min. The lumps were utilized as the catalyst of the carbon solidification reaction under the gas flow of CO at 600℃. The recovered solid carbon samples with different cementite/free carbon ratio were obtained by changing the reaction time. The composite made of the obtained carbon powder and hematite reagent was heated in order to proceed the reduction of the iron oxide and carburization of reduced iron. The molar ratio of carbon to oxygen in the composite was set as from 0.8 to 1.0. The composite started to be reduced at 700℃ and then reduction degree increased sharply at 900℃. The molten iron nuggets were observed on the surface of the composite samples heating up to 1300℃. These results indicate that the suggested carbon recycling ironmaking process may contribute to forward not only carbon neutrality but also rapid hot metal production.

Hill, Horst, Deutsche Edelstahlwerke Specialty Steel GmbH & Co. KG, Germany

Co-Author: Frank van Soest, Deutsche Edelstahlwerke Specialty Steel GmbH & Co. KG • Hans-Günter Krull, Deutsche Edelstahlwerke Specialty Steel GmbH & Co. KG • Andreas Mohr, Deutsche Edelstahlwerke Specialty Steel GmbH & Co. KG

Abstract: Additive manufacturing technologies like the laser powder bed fusion (LPBF) process are used in various industrial applications. The advantages like a possible complex shaped geometry or small lot sizes offers a high degree in freedom, for products as well as for research and development topics. But, in most cases materials with a low amount of carbon like the 1.4404 are used for LPBF. This material exhibits and easy processing with LPBF, but these kind of materials are not suitable for tooling applications. Tool steels like 1.2343 or 1.2344 offer a higher hardness and wear resistance, but the defect-free processing is complicated. And in addition, the small lot sizes of the different AM-processes are also a drawback for this technology. Especially regarding a scale-up to a mass-production with focus on tooling. Therefore, the aim of this paper is to identify chemical compositions that provides both: a good processing with LPBF and steel shop together with properties like wear resistance. This covers the whole life-time of a part, beginning from prototyping, to mass production and finally, spare-part production

Hofecker, Anna-Katharina, thyssenkrupp Steel Europe AG, Germany

Abstract: The identification of weaknesses and the analyse of production losses is crucial to ensure the stable output and the proper production planning of a coke plant. This is, compared to other steel production plants, faced by two main challenges that make the analysis complex: It never completely stops production and the redundancies of all important production components multiply information input. Coke plant Schwelgern started to implement a Digital Failure Reporting and Analyzing System to address this complexity.

Hohenbichler, Gerald, Primetals Technologies Austria, Austria

Co-Author: Manuel Sattler, Primetals Technologies Austria • Wolfgang Wichert, Lech-Stahlwerke GmbH

Abstract: Electric Arc Furnaces have always been the core plant and core process of Minimills, all over the world, because an EAF is THE scrap-based process of steelmaking. And it has always been a rather cheap production step as being based on electricity and not too complex, since the base material is already steel. The challenge however is to optimize the melting process, irrespective of the input material mix - and this is the biggest pain for most steel producers - for any type of target steel grade, as well as irrespective of the shift team, of the furnace lining, of environmental prescriptions and so on. Primetals Technologies has developed the Heat Cloning App, a preferred cloud based digital system to assure such operational optimization, using the real Level2 and Level 1 data of the EAF, hence using the real historical data of an EAF plant. Optimization objectives are stable tap-to-tap times, charge temperatures adapted to the needed overheating for the ladle furnace or the VOD and for the casting operations, and last not least the minimum operating cost. More than ever minimizing electrical energy per ton of liquid steel and minimizing the total amount of required specific energy are typical optimization objectives as well. Real data are showing that 5 - 10% better operations, reduced cost, higher margins are achievable by using Primetals' Heat Cloning App.

Hohenbichler, Gerald, Primetals Technologies Austria, Austria

Co-Author: Marvin Zemni, Primetals Technologies Austria

Abstract: Predictive Maintenance starts with IIoT. Excellent and reliable sensorics are the first hardware basement for lifetime and failure prediction for production machinery and plants. Therefore Primetals Technologies started technology development programs in data mining as well as condition monitoring and smart sensoric, even though the first approach has always been to perform condition monitoring without additional sensor implementation, where possible. A major source of unplanned downtimes of continuous slab casting plants are stuck bearings in the strand guide area. Hence Primetals Technologies has been realizing a prototype development creating a new middle bearing block with embedded sensors and an onboard tiny central processing unit, able to wirelessly transfer all interesting load data and performance indicators to the operators of the plant and to the maintenance personnel. The plant manager gets an overview about the overload events shift-by-shift or daily, weekly, and monthly, respectively. This paper provides a great insight into the first industrial prototype results.

Hollensteiner, Florian, Primetals Technologies Austria, Austria

Co-Author: Anna Theresa Strasser, Primetals Technologies Austria • Inge Aasheim, Primetals Technologies Austria • Gabriel Lenna Do Nascimento, Primetals Technologies Austria • Klaus Stohl, Primetals Technologies Austria • Michael Weinzinger, Primetals Technologies Austria • Irina Tolkacheva, Primetals Technologies Austria • Moritz Ortner, Primetals Technologies Austria • Georgiy Pervushin, Primetals Technologies Austria • Josef Boehm, Primetals Technologies Austria • Horst Puchner, Primetals Technologies Austria

Abstract: One of the goals of maintenance management is to maximize the return on investment in assets. This leads to an opportunity that transforms maintenance and repair service from a cost factor, into an activity which influences profitability and leads to a competitive advantage. Metallurgical companies worldwide are using condition monitoring, computerized maintenance management systems solutions or 24/7 remote services. But how to make your maintenance even smarter? Primetals Technologies integrates these processes and methods to add more value to them according to the synergy law: the whole is greater than the sum of the parts. More than that, these methods have been successfully implemented in current steel productions and brought numerous results including unplanned and planned downtime decrease, total cost of ownership reduction and equipment availability growth. An example including achievements of this smarter maintenance management solutions are presented in this paper.

Holler, Roman Markus, PSI Metals Austria GmbH, Germany

Co-Author: Joachim Gnauk, PSI Metals GmbH • Hannes Sperl, PSI Metals GmbH

Abstract: Blockchain technology is a potential game changer for the entire chain of the manufacturing industry. Over the past years, reliable tracking of goods using blockchain technology has become a major topic as it enhances transparency and traceability of products while revealing information like the history and origin of the products. While it is important to use blockchain technology to create a reliable and transparent traceability, such transparency partly reveals confidential information about production processes. This kind of scenario is not peculiar to special steel producers supplying sensitive industries, but also to conventional production chains where confidential information might be derived from the published information. In our paper, we will reveal how zero-knowledge proofs (ZK proofs) create increased transparent tracking while keeping confidential data. The standard EN 10373 describes certification of metallic products complying with EN 10204 using computational models based on sensor data captured during the production processes. By combining EN 10373 with blockchain technology and ZK proofs, producers can successfully compute the product’s quality without revealing anything about the production details. Keywords: Blockchain, Zero-Knowledge Proofs, Product Tracking, Transparency, Computational Models

Hong, Yul, Hyundai Steel Co., Korea, Republic of

Co-Author: Yun Mo Lee, Hyundai Steel Co. • Byong Chul Kim, Hyundai Steel Co.

Abstract: Suitable quality of sintered ore is a crucial factor for stable blast furnace process. However, it is difficult to predict various properties of sintered ore by identifying characteristics of blending ores such as ore size and chemical composition due to its complex reaction mechanism. Sintered ore is generated by assimilation process of granule particles composed of adhering fines and nuclei ores and its reactivity is changed by physical and chemical properties of iron ores. Especially, assimilation between coarse ores and fines is able to influence the sinter bonding strength. Therefore, this study aims to clarify influencing factors on assimilation process and identify correlation between sinter bonding strength and characteristics of coarse ore. To simulate sintering, pseudo particles were granulated with coarse ore (1-3 mm) and adhering fines which form primary melt and then sintered at 1623 K. The simplified Tumbler Index test (TI) was conducted to assess bonding strength of sintered ore particles. Iron ore Reactivity Indices (IRI) were obtained by evaluating TI values of 11 kinds of iron ore brands, respectively. As a result, physico-chemical properties of coarse ores such as gangue, LOI (Loss On Ignition) content and melting point influenced distinct assimilation properties. Coarse ore brand that undergoes intense assimilation reaction has higher IRI value and this phenomenon causes improving sinter bonding strength. Considering the association between Iron Blending ore Reactivity Index (IBRI) and quality of sintered ore generated in the sinter plant, we figured out that higher IBRI increases Shatter Index (SI) of sintered ore. This result shows that not only the comparison of the degree of iron ore assimilation reaction is able to rank each iron ore brands, but also it could predict quality of sintered ore dependent on IBRI.

Hopperdizel, Paulo, Lumar Metals, Brazil

Co-Author: Paulo Hopperdizel, Lumar Metals • Nerea Mendonza, ArcelorMittal Acindar

Abstract: ArcelorMittal Acindar has a capacity of 1,500,000 TON and is an integrated steel production plant, consisting of MIDREX Direct Reduction, Electric Arc Furnaces, Ladle Furnaces, Continuous Casting and Rolling Mill Plants. It produces a wide variety of types of steels, low - medium - high carbon, free cutting, construction, aluminum quenched and low alloy. Leading steel company in the long steel market focused on to increase efficiency and cost reduction of the steelmaking process, planned to revamp the chemical energy package changing the equipment of oxygen and carbon injection on the two 110 ton EAF’s with the goal of decrease the consumption of injected carbon, oxygen and better slag foaming. The two EAF using scrap as charge and feeding DRI continuously with three ports of burner/oxygen and carbon injection. This project consisted in replacing the existing three ports of burner/oxygen and carbon injection for a new EAF chemical package, composed by copper blocks, burners and injectors of oxygen and carbon. Searching for the best technology currently available in the market, Acindar chose the chemical package developed by Lumar to EAF, composed by Protect Block, FlexOx and Power Carbon (to the needy carburization points). In this paper will be presenting the chemical package equipment implemented in these EAF’s revamp, as well the installation project, besides the operational results obtained during startup. The main results were the reduction of the consumption of the carbon, oxygen, improvement of the formation of foaming slag and reduction of power consumption of the furnaces.

Hopperdizel, Paulo, Lumar Metals, Brazil

Co-Author: Paulo Hopperdizel, Lumar Metals • Atul Dubey, Jindal Steel & Power Limited • Raju Psjkk, Lumar Metals

Abstract: JSPL Angul is a integrated steel plant with the capacity to produce 6,000,000 tonnes of steel per year, located in the city of Angul, Odisha, India. Its industrial complex consists of a one Midrex direct reduction plant, with the capacity to produce 2 MILLION MT of Hot DRI / tonnes year, one Blast Furnace whith the capacity to produce 4 million MT of HotMetal / tonnes year, two melt shops, one meltshop with 1 electric arc furnaces of 250 tonnes, 1 ladle furnaces, 1 continuous casting and one melt shop with 1 BOF of 250 tonne 2 continuous casting and rolling mills. JSPL Angul during the hot commissioning of EAF meltshop worked with high amount of Hot Metal charged (around 85%), completing the charge with DRI (around 15%), for this mix of charge only chemical energy is required, and the efficiency of oxygen injectors instaled at EAF were not able to reach the performance required by JSPL Angul in these cases. The injectors installed not allow the use of all injector in the early moments of process, due high FeO generation, high height of foaming slag and slopping of slag through slag door. Due this, JSPL Angul planned the revamp of the chemical power package of EAF with the aim of reducing oxygen blow time and have high metallic yield of the heat. This work will present the equipment used, the concepts used in the remodeling project of the chemical package, as well as some of the results obtained after the implementation of this new equipment.

Hornig, Krzysztof, ANDRITZ Metals Germany GmbH, Germany

Co-Author: Vasile Jechiu, ANDRITZ Metals Germany GmbH

Abstract: Modern humankind will continue to need the products of the metal industry in the future, similar to the products of other key industries. Especially in the field of energy-intensive thermal processes in the steel industry, the high demand for process heat supplied today by the oxidation of fossil fuels is required in terms of process technology. The reversal from fossil fuels is the core task of the transformation towards sustainable thermal process technology. Therefore, traditional energy sources are replaced with CO2-neutral alternatives, i.e., green electrical energy and green hydrogen. On the path to sustainable thermal process technology, however, the following simultaneous efforts are fundamentally important as well: • A further increase in the thermal efficiency of the process while reducing emissions as harmful as NOx or dust emissions. • A reduction in material loss within the production chain. For example, material loss occurs during the heating process due to scale formation. • An optimal interlinking of the individual production steps to increase the production chains' overall efficiency. • All-round use of intelligent, connected, and user-friendly automation systems. These measures have a particularly sustainable effect in modernizations and upgrades, where omitting additional cumulative CO2 emissions due to the reuse of the already produced assemblies improves CO2 balance of the retrofitting effort. In the article, the innovative and practical solutions for heating systems in industrial furnaces for the steel industry are presented with the help of concrete examples. Furthermore, the complexity of the requirements for the industrial heating systems is analyzed. In particular, the latest developments with regenerative burners and hybrid heating systems

Hsu, Fu-Yuan, National United University, Taiwan, Province of China

Co-Author: Chi-Ming Hung, Metal Industry Research and Development Center • Yu-Lin Feng, Metal Industry Research and Development Center

Abstract: In the solidification simulation of shape casting, many sophisticated commercial modeling packages are accurate enough to predict the shrinkage porosity in the modeling results. However, it is difficult to produce autonomously a precise shape and geometry of an optimized feeder to avoid shrinkage porosity from the results solely. In this study, a so-called “casting shape analyzing technique (CSAT)” was developed and applied for the prediction of the solidification time for castings with complicated shapes. Using this technique, an optimized feeder for a complicated shape of casting could be calculated and generated. This feeder design is part of the casting process control for producing a good quality casting without shrinkage defects during solidification. For casting with complicated shapes, the relationship between the shape factor and the mold constant was established. Using this equation, the relationship between the solidification time and the geometry of a shape casting was correlated. As a result, solidification time and a required feeder volume could be predicted for an arbitrary casting shape. In this technique, an exact volume of a feeder could also be derived from the magnification equation. The precise shape and volume of the three-dimensional feeder geometry were autonomously produced from the equation. Four different sizes of ductile caliper castings with the same shape were successfully validated using this technique. It accurately predicted the required feeder size for these four calipers. The method and procedure to predict the solidification time and required feeder size for castings with complicated shapes were proposed in this study eventually. Keywords: process quality control, ductile iron casting, shape factor, mold constant, feeder design, shrinkage porosity.

Hubrich, Martin, VDEh-Betriebsforschungsinstitut GmbH, Germany

Co-Author: Matthias Kozariszczuk, VDEh-Betriebsforschungsinstitut GmbH

Abstract: In Germany, 85% of the total non-public water supply of 14 billion m³ (2019) is used in the area of plant and product cooling. Due to climate change, a continuous limitation of water withdrawal and wastewater discharge quantities in combination with increasing temporary or permanent water shortage can be observed, which can lead to a potentially negative impact on production or plant availability, especially in cooling and casting processes. Strongly varying cooling water and concentrate compositions (salts, hardening agents) as well as certain ingredients (e.g. organics) prevent the closing of the cycles or recycling. Innovative and easy-to-use desalination processes such as membrane-based capacitive deionization are available but have not yet been adapted to the requirements of the iron and steel industry with regard to the complex water matrix. As a result, there is a need for solutions to deal with these temporary situations by using wastewater as an alternative water source to ensure the water supply and developing suitable process approaches for producing mono concentrates from the desalination concentrate as a prerequisite for material recycling. For this purpose, the use of membrane-based capacitive deionization, which has already been successfully tested in the field of cooling water treatment, is considered in more detail. The focus of the current BFI work is the treatment of organic and solid-containing wastewaters from chemical-physical treatment plants or biological treatment plants for the treatment of degreasing baths and old emulsions as well as a for a central treatment plant before discharge. Another focus is the determination of potential impurities and their removal to ensure reliable and energy-efficient process technology for wastewater desalination. At the same time, the production of mono-concentrates from the resulting mixed concentrates for the electrochemical production of a chlorine-based biocide for direct use in cooling circuits is being investigated.

Huelson, Eric, OnPoint Digital, Inc., United States

Co-Author: Jonathon Richards, Tata Steel Ltd • Guillaume Tiffon, OnPoint Digital Solutions, LLC

Abstract: Combustion control in a reheat furnace is an often-overlooked opportunity for fuel savings and steel quality improvements. With recent increases in natural gas and energy costs, fuel efficiency is more important than ever for maintaining viable steel production. Despite this many of today’s reheat firing schemes are based on rudimentary mass flow indicators and minimal control logic resulting in high levels of excess O2 (4%-8%) and significant extra fuel consumption worth hundreds of thousands of dollars annually. A simple solution is presented for zone-based combustion monitoring using a TDLAS laser monitoring system in a reheat furnace. The system has been used to spot failings caused by poor burner calibrations and targeted firebox corrections at a large steel mill. Moving forward control logic updates are planned to help improve furnace efficiencies and reduce fuel consumption. Furnace corrections and proposed efficiency solutions will be reviewed to illustrate the optimization journey and combustion improvement opportunities.

Humer, Veit, Primetals Technologies Austria, Austria

Co-Author: Josef Watzinger, Primetals Technologies Austria • Michael Speher, Primetals Technologies Austria • Markus Nolan, Primetals Technologies Austria

Abstract: Product quality, machine throughput and process safety are certainly the most important parameters in continuous casting. One crucial precondition to support those parameters is a stable mold level. If unstable, often non-uniform shell growth and casting powder inclusions occur. This can lead to various slab defects like cracks or bad slab surface quality. A totally new technology offers a proven solution in mold level stabilization: Unsteady bulging compensation via casting gap modification. Great results have been achieved in producing a very steady meniscus position and in the improvement of the mold flow conditions. This has an immediate effect on product quality. An analysis of production data and quality indicators like slab downgradings supports this statement. More specifically, all the data is put into relation to those quality defects and the results are compared to conditions with less performant mold level control.

Husakovic, Adnan, Primetals Technologies Austria, Austria

Co-Author: Klaus Grasserbauer, Primetals Technologies Austria • Andreas Melcher, Primetals Technologies Austria • Dietmar Hofer, voestalpine AG • Wolfgang Höfer, voestalpine AG • Anton Tushev, Primetals Technologies Germany • Ali Abbas, Primetals Technologies Austria

Abstract: Green steel production requires a better knowledge of processes and their optimization. The advances in data science and hardware capabilities within recent decade provided new digitalization methods. Two of the most prominent areas recently discussed in science are computer vision and data-driven process modelling. The scrap consistency and EAF-process model gain additional insights and potentials towards EAF-process stabilization and improvement. Within the scope of this paper, we show the importance of Computer Vision and data-based modelling on two use cases: scrap composition monitoring and EAF-process modelling. It summarizes the benefits for the steel producer.

Huss, Joar, Swerim AB , Sweden

Co-Author: Du Sichen, Hybrit Development AB • Niklas Kojola, Hybrit Development AB

Abstract: Phosphate capacity data has been used by steelmakers for many decades to optimize the dephosphorization praxis in various reactors, e.g. the BOF and the EAF. The data is commonly gathered in a laboratory where the partial pressure of oxygen can differ significantly from the industry. The use of this data in the industrial case requires careful consideration. For slag systems containing multivalent slag species, e.g. Fe and Cr, the slag structure will be dependent on the valence state of the ions. This will lead to a variation in the thermochemical properties with the oxygen potential. For instance, the presence of Fe+2 and Fe3+ could lead to a substantial dependence of the phosphate capacity on the oxygen potential. To illustrate the effect of oxygen potential on the phosphate capacity, experiments were carried out in a resistance heated furnace at 1873K. In the experiments, vanadium oxide was used as the multivalent species, to limit the reaction with the crucible. The phosphorus partition between liquid copper and a fully liquid, MgO-saturated, SiO2-MgO-VyOx slag was determined at different oxygen potentials in a controlled atmosphere. To set oxygen potential in the system (1.72 × 10-8 – 1.73 × 10-11 atm), CO-CO2 mixtures were used. The resulting phosphate capacity change one order of magnitude over the investigated oxygen potential range. Based on the present results, the applicability of phosphate capacity data gathered at a different oxygen potential than the prevailing in an industrial process is questionable. In effect the data could even mislead the engineer in its implementation. This is especially the case considering that the oxygen potential in the reactor slag varies with position and even time. Using phosphate capacity data for the process should as such be done cautiously even if the data is gathered at a relevant oxygen potential.

Hyllander, Gunilla, Hybrit Development AB, Sweden

Co-Author: Christer Ryman, Hybrit Development AB • Marcus Henriksson, Hybrit Development AB • Hannes Wikström, Hybrit Development AB • Petrus Hedlund, Hybrit Development AB • Damian Guido, Hybrit Development AB • Nicklas Eklund, LKAB • Per Lundström, LKAB • Hedda Pousette, SSAB AB • Anna-Maria Suup, Hybrit Development AB • Per Hellberg, Hybrit Development AB • Jenny Wikström, LKAB • Shabbir Lakdawala, LKAB • Joel Carlsson, SSAB AB • Niklas Kojola, SSAB AB • Johan Riesbeck, Hybrit Development AB • Gunilla Hyllander, Hybrit Development AB

Abstract: The iron and steel industry contributes globally with a share of up to 7% to greenhouse gas emissions. The goal of the HYBRIT initiative is to realize a fossil-free iron and steel production value chain. In this value chain the fossil CO2 emissions associated with the traditional blast furnace route are eliminated by using a 100% green hydrogen based direct reduction process. Starting from today's conventional natural gas based direct reduction technology, a shift to hydrogen as reduction gas introduces significant changes to the process chemistry and thermodynamics. A direct reduction pilot plant, including all safety installations required for hydrogen operation, has been designed and commissioned to develop best practices under semi-industrial conditions. The plant has a capacity of 1 tonne DRI per hour. Typically, the plant is run in campaigns where continuous operation takes place for a period of about 6-8 weeks. After initial design and construction of the pilot plant the trials started at the end of 2020 with natural gas and continued in early 2021 with the use of hydrogen as reduction gas. This paper provides key operational results from H-DR test trials conducted in the approximately 43 weeks of operation until today. DRI and HBI products have been successfully produced on pilot-scale under stable process conditions using 100% green hydrogen as reduction gas. Sponge iron produced with hydrogen as reduction agent is a carbon-free product. This DRI product has better physical, mechanical, chemical and reactivity characteristics compared to conventional DRI produced with natural gas. The results also demonstrate the technical feasibility to define a process window for production of DRI and HBI in an industrial DR plant based on green hydrogen.

Ilmola, Joonas, University of Oulu, Finland

Co-Author: Jari Larkiola, University of Oulu • Oskari Seppälä, University of Oulu • Joni Paananen, University of Oulu

Abstract: Digitalization is taking a bigger role in the steel industry. Models for predicting mechanical properties, metallurgical phenomena, roll forces and microstructure have been commonly used in development of novel steel grades. These individual models may predict certain phenomena thoroughly, but input values are usually based on an assumption or on a “good guess”. To produce reliable boundary conditions for these models of individual phenomenon a virtual rolling model is developed. This model computes the whole process of the hot strip mill from roughing to accelerated water cooling on a run-out table. Strip location and temperature evolution is calculated continuously. Thermal and thermomechanical (rolling stands) boundary conditions are placed according to process layout. Input data for the model is automatically read from raw process data. Rolling parameters are calculated using a coupled ARCPRESS model which calculates normal and frictional shear stress distributions in the roll gap predicting roll forces and displacements of the work roll surface. Calculations for static recrystallization are considered in evolution of flow stress. Phase fractions during water cooling are calculated as well. The virtual rolling model minimizes the need for parameter speculation for each simulated process. All the input values are read from actual process data and the metallurgical and mechanical state of the strip are computed through-out the whole process.

Ishfaq, Mir, Indian Institute of Technology Bombay, India

Co-Author: Manish M Pande, Indian Institute of Technology Bombay

Abstract: Insoluble oxygen constitutes a substantial portion of total oxygen in the Al-deoxidized steels. The concentration of dissolved oxygen increases as the Al concentration increases beyond a certain critical value. In some steel grades, Al requirement is much higher than that is required for deoxidation. In the present work, the insoluble oxygen in such high aluminum steels has been estimated and compared using two different techniques: (i) two stage heating method in inert gas fusion infrared absorptiometry to differentiate soluble oxygen and insoluble oxygen. In the stage I, the sample was first heated to a temperature of 1873 K to remove all the dissolved oxygen. SEM studies showed that alumina inclusions were still present and were not removed by carbothermic reduction after stage I. In stage II, the sample was heated to 2613 K at which the alumina inclusions (insoluble oxygen) were reduced by the graphite. (ii) A Scanning Electron Microscopy Automated Inclusion Analysis (SEM-AIA) was used to estimate the size and number of inclusions in the steel samples. The insoluble oxygen was estimated, by Area Fraction (AF) method from the SEM-AIA data.

Janáková, Nella, Progres Ekotech, s.r.o., Czech Republic

Co-Author: Martin Gajdzica, Progres Ekotech, s.r.o.

Abstract: Reducing CO2 Emissions: Industrialization of the hydrogen reduction technology will take some years and further time will pass by until all blast furnaces worldwide will be substituted by hydrogen technology. A bridging technology EcolBriq® offers tremendous value by reducing CO2 emissions on the regular BF production route partially substituting the iron ore sinter process. Recycling of by-products: Recapturing the valuable elements of by products and reducing landfill quantities is another EcolBriq® application creating a cost advantage. The paper presents a cold technology to produce a low-carbon BF feedstock which can be used to supplement the sintering process of iron ore as it is currently known. The implementation of this production process of BF feedstock results in lower energy consumption compared to the high-temperature process of sintering. Thus, there is a significantly lower carbon footprint. In addition, the technology contributes to efficient re-utilization of by-products from metallurgical processes like scale and fractions of dust and slag. A single production line can be utilized for a wide variety of materials as feedstock with different structures, eg: from powder to lumps, minerals like oxide or metal ships with sizes 0-200 mm. The variety of advantages will be discussed: i. Reduction of CO2 emissions for production of the EcolBriq® feedstock compared to sinter ii. Dust reduction for EcolBriq® compared to sinter plant iii. Maximizing the efficiency of the circular economy in BF operations iv. Reducing energy intensity Two case studies will show the results of briquetting two materials which cannot be recycled in sintering plant. First study is focused on briquetting of fine fraction of desulfurization slag and the second one will discuss recycling of oily scales.

Jaouen, Olivier, Transvalor S.A., France

Abstract: During the ingot casting, several kinds of particles can appear or be introduced in the cavity by the bucket. Lots of different reasons can explain this kind of foreigner bodies in the ingot. Some of them come from the liquid metal initially in the foundry bucket, the sand mold interaction, the riser or the slag interaction. These oxides particles, sand particles or other kind of inclusions could induce issue of metallurgical health of the ingot after cooling but also in the forward steps. It’s why lot of scientific projects are working on the slag/liquid metal interaction, entrapment of powder and all kind of defects and inclusions. Some embedded abrasive and inclusion generation models are already available in the state of the art and already used in our THERCAST® solution. We can also introduce different kind of particles (size, density) and follow their trajectories during the pouring. The main idea is to provide an appropriate software able to anticipate each inclusion generation and tracking at the end of the ingot casting process. Thanks to the global ‘End-to-End’ process simulation approach offered by Transvalor platform, it is possible to estimate the consequences during the next step of the metal transformation (forging, heat treatment). This presentation will show us how THERCAST® manage this kind of phenomena and the integrated physical models.

Javaheri, Vahid, University of Oulu, Finland

Co-Author: Jukka Kömi, University of Oulu • Saeed Sadeghpour, University of Oulu • Sakari Pallaspuro, University of Oulu

Abstract: Abstract: Isothermal bainitic transformation below the Martensite start temperature (MS) has been reported in previous works [1,2]. The current study investigates the effect of bainite formation below the MS temperature where the athermal martensite formation is interrupted, on the final tensile properties. The studied material is a 0.4 (wt.%) carbon, low-alloy steel subjected to different thermal cycles in order to produce different fractions of martensite and bainite. Gleeble 3800 thermo-mechanical simulator machine was employed to perform all the cycles as well as to provide the dilatometric data. In the experiments, each sample was heated to the temperature of 850 °C at a rate of 50 °C/s and was held for the 30s. Then, the samples were quenched to a temperature between MS and MF followed by a subsequent isothermal holding in the MS–MF temperature window. A field emission scanning electron microscopy equipped with an electron back-scatter detector was used for microstructural characterization. The results showed that low-temperature bainite formation below the MS significantly improved the ductility of the samples although the strength decreased slightly. References: [1] S. Samanta, P. Biswas, S. Giri, S.B. Singh, S. Kundu, Formation of bainite below the M temperature: Kinetics and crystallography, Acta Mater. 105 (2016) 390–403. https://doi.org/10.1016/j.actamat.2015.12.027. [2] S.M.C. van Bohemen, M.J. Santofimia, J. Sietsma, Experimental evidence for bainite formation below Ms in Fe–0.66C, Scr. Mater. 58 (2008) 488–491. https://doi.org/10.1016/j.scriptamat.2007.10.045.

Javurek, Mirko, Johannes Kepler University, Austria

Co-Author: Sergiu Ilje, voestalpine Stahl GmbH

Abstract: In bow-type continuous slab casters, non metallic macro-inclusions (size 50 to 200 μm) are concentrated in a small band over the strand thickness, also called „quarter depth inclusion band“. This effect was observed in measurements and can be explained theoretically by the bow geometry in combination with the upwards drift velocity of inclusions in the liquid steel due to the density difference. Measurements also showed that the inclusion distribution is often significantly inhomogeneous and asymmetric over the strand width. Theoretical considerations explain this effect by an inhomogeneous flow pattern in the bending zone of the strand. In this contribution, transient numerical flow simulations of the liquid steel inside of the strand with the scale resolving SAS turbulence model in combination with non-metallic particle transport are presented. The time scales of the flow fluctuations in the bending zone showed to be quite large. Therefore, one hour of the casting process was simulated, which requires about one year of computation time. Two cases without and with argon gas injection at the stopper rod tip were considered. The injected gas is assumed to form bubbles, that are transported with the liquid steel flow into the mold and influence the mold flow by their buoyancy forces. The results show irregular fluctuations of the inclusion distribution with alternating asymmetric profiles over the strand width, with time scales in the order of magnitude of several minutes, corresponding to strand length distances of several meters. The case with argon injections shows slightly lower peak concentrations than the case without gas injection.

Jax, Klaus, Primetals Technologies Austria, Austria

Co-Author: Norbert Hübner, Primetals Technologies Austria • Wolfgang Oberaigner, Primetals Technologies Austria

Abstract: "Continuous product improvement based on steel producers requirements is an essential part of the TPQC success story. But how can TPQC users take advantage of these? This paper describes the latest developments in the area of TPQC. Among the developments are improvements of the Statistical Process Control (SPC) functionality, now supporting an electronic logbook of changes and measures applied to the process, and digital guidance to select the right measures when SPC alarms occur. Other new features comprise extended support for data recording, visualization and evaluation for the liquid steel production and visualization of data for entire campaigns such as tundish sequences. Integration of prescriptive AI models make it possible to online react to process deviations to adapt the next process in order to reach the required product quality targets. TPQC is now available as subscription license to ensure that the system is always at the latest state and steel producers can benefit from the new features of the system and become a lifecycle partner of Primetals Technologies. The paper further explains success stories of projects in which TPQC is interacting with Primetals Technologies' production management system (PMS) and condition monitoring system (ALEX) to maximize the benefits and to make a big step towards the Digital Unity vision of Primetals Technologies. ALEX can provide valuable information about the condition of the production facilities to TPQC via a plug & play interface and such enabling TPQC to even more precisely decide on necessary measures to ensure that the products will meet the required quality. The interaction with the PMS ensures that the product transport and necessary further production steps can automatically be controlled based on on-line quality decisions and remedial measures proposed by TPQC."

Jensen, Sven, Dürr Systems AG, Germany

Abstract: Gas prices in Europe will remain on a high level. Therefore, any gas fired process should be examined in regard to energy efficiency measures. Gas fired ovens are widely used in the steel industry. Very often the temperature of the exhaust gas at the stack is still in the range of 300 °C to 600 °C. The so called high-temperature ORC technology is an ideal tool to make use of that waste heat. Taking the example of an innovative ORC system installed at the site of a German steel mill, the lecture will present the achievements and challenges of two years of operation. In this project, the residual heat of the exhaust gases of a walking beam furnace is transferred in one-step to the ORC working media by using direct evaporation technology. As a consequence of capturing the thermal energy at high temperature levels of around 450 °C, the water-cooled condenser of the ORC system can be operated at an elevated temperature of up to 90 °C. The ORC system provides a two-fold benefit to the Customer. The turbogenerator feeds up to 500 kW electric power to the factory and, thus, reduces the expenses for purchasing power from the grid. Moreover, the ORC system transfers around 2.3 MW of heat to a district heating network. After commissioning in July 2020, the plant has been running several thousand operating hours. The presentation analyzes operating data and compares it to the project targets. Further explanations are given how the ORC system is integrated into the operational regime of the gas-fired walking-beam furnace. Finally, an exemplary economic calculation provides insights to the business case and highlights the benefits of an investment into a high-temperature ORC system as an energy efficiency measure: CO2 reduction, income from electricity produced, income from secondary thermal energy provided.

Jeon, Jiho, Hyundai Steel Co., Korea, Republic of

Co-Author: Wongyeom Kim, Hyundai Steel Co. • Wonjin Choi, Hyundai Steel Co. • Honggil Moon, Hyundai Steel Co.

Abstract: Vaccum degassing (VD) of steel melts during ladle treatment is an important process for removal and control of detrimental impurity elements. In order to complete homogenization and refining of molten steel in a short time, the molten steel is stirred by Ar gas injection from bottom of ladle during VD process. In the present study, a vibration-based monitoring system for gas injection was applied to consistently control the stirring intensity of volumetric Ar gas injection during VD process because various operation conditions in ladle affect the flow rate of Ar gas injection. The vibration energy generated by gas injection in the molten steel during VD process was measured on the wall of vessel in vacuum tank degasser. The vibration-based monitoring system was optimized by the various plant trials observing consistency of composition in the molten steel. The plant trials during VD process showed that the increase in stirring intensity enhances the removal rate of impurities and homogenization of molten steel in the ladle.

Jeong, Eunju, POSCO, Korea, Republic of

Abstract: Recently, many steel companies has been developing technologies for the realization of SMART steel making process. POSCO is also highly interested in automation process using smart technology in each process field to realize the smart factory. Papers and patents on automation process easily searchable across countries, and commercial technology products are on sale. Most of the automatic refining technologies aim at the dynamic control linked to the real-time decarburization characteristics while the static control by statistics proceeds. In this paper, the refining automation system in the AOD process that is being carried out at POSCO is introduced. In general, control of Oxygen-Nitrogen(or Argon) blowing step, basic weight and input of raw materials and temperature measuring and sampling of sub-lance are all performed manually by operators in AOD. Although this works are carried out under the standard, there is an operating deviation due to human factors. Therefore, an automatic refining technique was developed to reduce these human deviation factors in this study. In this automatic refining system, the decarburization state in the vessel is tracked in real time using the off-gas analyzer, and the end point of the each decarburization step is determined according to the criteria set and the blowing step is switched automatically. The raw materials to be added in the AOD process in order to match the ingredients for the steel are set in advance before the operation. When the automation of blowing starts, the raw materials are automatically weighed and put into the vessel according to each blowing step. Sampling for temperature and component confirmation of molten steel is also automatically performed at the designated time. Through this automatic control technology, it is confirmed that the operation deviation and amount of oxygen consumption was reduced.

Jipnang, Elena, SMS group, Germany

Co-Author: Atsushi Sugiyama, Midrex Technologies, Inc. • Leander Reuter, SMS group • Tim Kleier, SMS group • Brett Belford, SMS group

Abstract: In view of the global climate emergency, the iron and steel industry bears a special responsibility. Around 30% of global industrial CO2 emissions are generated in the steelmaking value chain. Since there are several alternative ways to reduce CO2 emissions, which perform differently depending on factors like energy infrastructure and raw material availability and prices, an individual transition roadmap to less carbon-intensive steelmaking must be analyzed for each steel mill. The overall process simulation and subsequent analysis help to make the right decision between different green steel production route options. This paper focuses on a steady-state flowsheet simulation in HSC, which was defined and performed using a case study to illustrate how the simulations can be effectively applied to design and optimize the steel value chain in a DRP-OBF-BOF-EAF configuration. This thermochemical process simulation enables process designers and plant operators to rapidly determine the impacts on CO2 footprint and OPEX due to variations in pellet quality, fuels, point of raw material addition and distribution of the products within the flowsheet. It is further demonstrated how scrap and waste circularity within the process can be optimized to balance OPEX and CO2 impacts.

Joly, Thierry, Vesuvius Europe, France

Co-Author: Mathieu Dombrowski, Vesuvius Sp. z o.o • Isenbarger Roger, Vesuvius

Abstract: Taphole clay as a key element in the proper functioning of the ironmaking process as it protects the ceramic hearth over time from damage by pig iron or slag. Using poor quality clay can be detrimental and leading to higher costs and early maintenance of BF hearth. Markets needs for sustainable products were another important factor for this evolution. Development of a binder for taphole clays which does not contain Polycyclic Aromatic Hydrocarbon and Formaldehyde was a game changer in the industry that strives towards sustainable future, which is available worldwide with performance at least equivalent to standard product, allowing cure speed of the mass to be adjusted and short inter-cast times. However, in some rare cases, we observed a hardening of the taphole mass in the plugging machine - this phenomenon required further development. Performing analytics and tests to reduce this hardening phenomenon, correlated to the high temperature in the mud gun, by developing a binder-based Formaldehyde and PAH free-tech with a higher boiling temperature. By increasing the boiling temperature of the binder, we succeeded in shifting the setting of the binder to higher temperatures, which solved the hardening problem in a way that exceed our expectations. Our methodology includes study and field trail of the implemented approach with an objective to replace the binding system without changing the formulation of the taphole mix concluding that this evolution of the binder has a positive influence on the length of the tap hole, duration of the casting and the specific consumption of the taphole clay in grams per ton of hot metal. Application in the field shows increased performance relative to traditional binder systems and does not require any reworking of the THC formulation, it can be easily substituted currently supplied materials with positive impact on health & environment.

Dr. Juchmann, Peter , Director Technology Development Direct Reduction, Salzgitter Flachstahl GmbH, Germany

Co-Author: Ulrich Grethe, Unit Manager Steel Production, Chairman of the Executive Board Salzgitter Flachstahl GmbH

Abstract: Steel is and remains a universally applicable, fully recyclable and therefore probably the most sustainable material of the future. As a key economic sector, the steel industry has a particular responsibility for future generations in terms of sustainability and climate protection. In close cooperation with society, politics, suppliers and customers, the way has been paved for a rapid reduction in greenhouse gas emissions and the achievement of climate neutrality by 2045. The individual CO2 roadmaps of European steel producers favor a natural gas- and increasingly hydrogen-based direct reduction of iron ore combined with a growing recycling share as the most sustainable route for primary steel production. With its Strategy 2030, Salzgitter AG is focusing on an intensified circular economy and the SALCOS® (Salzgitter Low CO2 Steelmaking) transformation project. In this context strong partnerships along the complete value chain, from raw materials, renewable energy and green hydrogen to plant construction and the growing customer base for climate-friendly steel products, including closed loops of high-grade scrap, are an important factor of success. The implementation of SALCOS® has begun and is speeding up considerably. By 2026, the first transformation stage with direct reduction plant, electric arc furnace and water electrolysis will go into operation. In 2033, the entire conversion of the integrated steel works in Salzgitter is scheduled to be completed. What is important now are clear international definitions and suitable regulatory framework conditions for climate-neutral hydrogen and green steel as well as the accelerated expansion of energy infrastructure and hydrogen economy. Salzgitter is further proceeding consistently. The new demonstration plant for the direct reduction of iron ore (µDRAL), which was successfully commissioned, has already produced the first CO2-free sponge iron based on 100% hydrogen, a further important step in our SALCOS® transformation.

Jun, Yeongjin, Hanyang University, Korea, Republic of

Co-Author: Sungjin Park, POSCO • Soochang Kang, POSCO • Joohyun Park, Hanyang University

Abstract: According to the global carbon neutral policy, the hydrogen energy market is growing and interest in hydrogen fuel cells is growing too. For the fuel cell separator, the Ti-containing ferritic stainless steels are used due to their high corrosion resistance, electrical conductivity, and durability. In a conventional steelmaking process, final steel quality is mainly affected by continuous casting tundish operation. In particular, the refining of Ti-added ferrite stainless steel and the relevant cleanliness have been improved via vacuum-oxygen-decarburization (VOD) and ladle treatment (LT) processes. However, the reoxidation phenomena inevitably occur during melt transfer from ladle to continuous casting tundish, resulting in a loss of titanium yield in conjunction with a formation of reoxidative inclusions. Hence, the present works aims to systematically investigate the combinational effect of different tundish fluxes on the reoxidation behavior of Al-killed stainless steel melts containing Ti. Rice husk ash (RHA), MgO (M) powder, and CaO-Al2O3 (CA) based fluxes were used for the experiments. When the molten steel was covered by M+CA fluxes, the average size of inclusions decreased, and it was confirmed that most the of inclusions were liquid (Ti2O3-Cr2O3-Al2O3) system. On the other hand, when the RHA+CA fluxes were added, the average size of inclusion decreased, whereas total number of inclusions significantly increased due to a reoxidation reaction by SiO2 in RHA. When the M+RHA+CA combinative fluxes were added, the size of inclusion decreased, and the number of inclusions exhibited a value between the M+CA and RHA+CA conditions. Consequently, a decrease in total oxygen content was largest in M+CA flux combination experiment.

Jung, Sungmo, Pohang University of Science and Technology, Korea, Republic of

Co-Author: Sung-Wan Kim, POSCO • Seoungkyu Cho, Pohang University of Science and Technology • Leonardo Rocha, Pohang University of Science and Technology

Abstract: CO2 gas is significantly generated from sinter plants and blast furnaces. It is necessary to reduce the fuel ratio in the sinter mix to decrease the CO2 emission from sinter plants, which will harmfully affect the melt formation and sinter quality consequently. To overcome the loss in the amount of melt, the current study aims to clarify the effect of adding iron ores-based calcium ferrites to the sinter mix on sinter quality and emission of CO2. The addition of calcium ferrites promoted a significant drop in sintering temperature while maintaining the porosity level. The presence of calcium ferrites led to the formation of finer pores, modifying the dominant pore size in the sinter from macro (>100µm) to medium/micropores (<100µm). The amount of SFCA and SFCA-I phases was significantly increased from 9% of the standard sinter to at least 32%. The aforementioned modifications were determinant to the improvement of the physical properties of the sinter, in terms of the degree of reduction and RDI, by at least 24 and 26%, respectively. Due to the decrease in the sintering temperature, the required fuel ratio is expected to decrease by more than 30%, and consequently, the identical reduction ratio has resulted in the emission of CO2. A low-temperature sintering process could be designed by adding calcium ferrites to the sinter mix. Considering the sinter products with a similar porosity level, the refinement of the size of the pores made by adding calcium ferrites might contribute to a better and homogenous percolation of hydrogen gas through the sinter during the reduction process inside the blast furnace, as the hydrogen molecule is known to have a smaller size than the CO molecule. Besides, through the improvement of sinter reducibility and strength, less coke would be required inside the blast furnaces.

Kaijalainen, Antti, University of Oulu, Finland

Abstract: Formed steel sections are widely used in construction applications due to their relatively high strength and stiffness properties. Especially, cold-formed welded hollow sections provide cost-efficient and environmentally friendly alternatives compared to hot-formed sections. Cold deformation causes work-hardening of the material, which resulting in enhanced strength, although a corresponding loss of elongation and toughness. The aim of this work is to compare mechanical properties of i) as produced, ii) artificial aged (250 °C for 1 h) and iii) naturally 5-years aged cold formed S700 rectangular hollow section. The investigated hot rolled steel strip was produced thermomechanical rolling followed by direct quenching. The dimension of the investigated hollow section was 120x120x10 mm and the corner radii and the other tolerances compliant with EN 10219. Tensile properties and Charpy-V impact toughness were determined for the flat and corner area of the hollow section. The results showed that the tensile strength in the corner was slightly higher in comparison with the flat side, revealing higher cold deformation rate in the corner. Artificial ageing increased the strength level relatively higher than cold forming without losing any elongation properties. The impact energies were at the high level at -40 °C and -60 °C in cold formed and aged materials. Even at -80 °C, the CV results were 118 J/cm2. It is also notable that no difference in CV values between the flat and the corner samples were observed. Thus, the results showed that the flat side specimens testing provides sufficient information of mechanical properties of the cold formed rectangular hollow sections and no need demanding corner sample testing when the structural hollow section is produced by using the thermomechanical controlled and direct-quenched base material. Furthermore, results showed that cold formed S700 is excellent for offshore steels, as steels are used even colder conditions as before.

Kalugin , Mikhail , KALUGIN Top Combustion Solutions, Serbia

Co-Author: Boris Prokofyev, KALUGIN JSC • Yury Murzin, KALUGIN JSC • Anton Subbotin, KALUGIN JSC • Sergey Ivlev, KALUGIN JSC

Abstract: The global iron and steel industry is being impacted by a decline in steel demand and volatile situation in the global market of raw materials. Manufacturers are challenged to reduce the production cost of iron and steel by modernizing the existing production facilities in conditions of continuously growing requirements for provision of environmental measures. Iron and steel industry is considered as “dirty” production and many processes, including blast-furnace production, are sources of a big amount of combustion products and CO/NOx emissions. Many designs of hot stoves used for blast furnaces are not able to provide complete gas combustion during operation. On the contrary, top combustion stoves which have gained widespread use recently have proved its capability to remain environmentally “clean” during long-term operation. KALUGIN Company has developed and successfully implements top combustion hot blast stoves of its own design representing advanced and economically efficient technology meeting today’s high environmental requirements. Nowadays, modernization of existing stoves is being performed with different modernization options from replacement of existing burner design to full replacement of the stove. This paper gives a comprehensive assessment of various modernization options on the basis of such parameters as productivity, capital expenditures, project implementation period, reduction in CO and NOx emissions, which enables to choose the best option for modernization of existing facilities to improve productive efficiency and significantly reduce harmful emissions having adverse environmental impacts.

Kamalasekaran, Arun, KTH Royal Institute of Technology, Sweden

Co-Author: Pelle Mellin, Swerim AB • Christopher Hulme, KTH Royal Institute of Technology

Abstract: Ferronickel (FeNi) alloys are widely used to manufacture stainless and heat-resistant steels. They are also used as an alternative binder in tools, replacing Ferro-Cobalt. Typically, FeNi alloys and alloy powders are produced by processes that use carbon as a reductant and emit large volumes of greenhouse gases. In the current work, FeNi alloy powders with varying compositions were produced by directly reducing Fe2O3-NiO powder mixtures using hydrogen to replace carbon as the reductant. This could prevent millions of tons of greenhouse gas emissions each year in Sweden alone, and reduce energy consumption significantly. The mixtures of Fe2O3 and NiO powders were directly reduced using hydrogen in a horizontal tube furnace in which the products were analysed using a gas analyser based on photoacoustic spectroscopy. The preliminary results from the gas analyser indicated that the mixtures reduced completely at a temperature of 700°C within 45 minutes. This was confirmed using X-ray diffractometry (XRD). The XRD data revealed the absence of oxides in the reduced powders and the presence of a single solid phase: gamma (FCC) or two solid phases: alpha (BCC) and gamma (FCC), depending on the ratio of the iron and nickel oxide powders in the initial mixture. Analysis using energy-dispersive X-ray spectroscopy in a scanning electron microscope showed that the average composition of a mixture of oxide powders that contained a mass ratio of 78 wt% iron and 22 wt% nickel was 85 wt% iron and 15 wt% nickel. This is promising enough to justify further investigation. Successful application of these results could replace traditional pyrometallurgical processes with a clean, lower-energy production route and thereby save large amounts of carbon emissions and energy.

Kang, Youn-Bae, Pohang University of Science and Technology , Korea, Republic of

Co-Author: Jun Hyun Kim, Chosun Refractories Co., Ltd. • Joo-Hyeok Lee, POSCO • Yong-Min Cho, Pohang University of Science and Technology • Dong-Jun Lee, Pohang University of Science and Technology

Abstract: Continuous casting of liquid steel from tundish to mold is performed by flowing the liquid steel through SEN. However, the inner hole of the SEN is often clogged, and consequently, the casting process is interrupted. The clogging deposit also falls off, enters into the liquid steel in the mold, and eventually appears on the surface of the cast product. Suppressing nozzle clogging is therefore essential to increase the productivity and quality of the cast product. While various origins have been identified for causing nozzle clogging, the present study focuses on the reaction chemistry-based aspect. The initiation of the clogging is due to an interfacial reaction between the inner wall of the SEN and the liquid steel passing through the SEN. In particular, the carbothermic reaction inside the SEN (SiO2(ref.) + 3C(ref.) = 2CO(g) + SiC(s)) generates CO(g), which causes reoxidation of the liquid steel, resulting in clog deposit formation. This initial clog deposit can be a subsequent build-up site for inclusions in the liquid steel. Therefore, it is necessary to suppress the reoxidation. In the present study, the fundamental reaction is discussed in view of thermodynamics, a series of laboratory-scale experiments including in-situ gas analysis in the emitted gas, and proposals to suppress the CO(g) generation. Three approaches will be shown: 1) minimizing SiO2/C ingredients, 2) adding CO absorbers, and 3) replacing SiO2/C ingredients with non-oxide type ingredients (oxynitride-nitride mixture) in the SEN refractory. Significantly improved results were obtained, in terms of suppressing clog deposit growth and casting plant trials.

Kang, Youn-Bae, Pohang University of Science and Technology , Korea, Republic of

Co-Author: Michael Bernhard, Pohang University of Science and Technology • Kang-Ho Bang, POSCO • Soon-Jong Jung, POSCO

Abstract: One of the industrial wastes after alumina production from bauxite, red mud, was assessed as an additive to lime, as a new desulfurization flux for the hot metal in the steelmaking process. Its role in facilitating the melting of the lime was primarily investigated. Keeping in mind that the desulphurization mechanism under mechanical stirring such as in the KR process is different from that without mechanical stirring, a series of laboratory scale tests were carried out with a device for inducing mechanical stirring in the hot metal. A number of variables (mixing ratio between lime and red mud, pre-reduction of red mud, mechanical stirring, and additives to the lime/red mud mixture) were employed in order to elucidate the desulphurization mechanism and optimum chemistry of the desulphurization flux. In order to assess the desulphurization efficiency in a more quantitative manner, a “DeS Index” was defined. This takes into account the extent, rate, and cost of the desulphurization simultaneously. With this index, it was found that the presently developed red mud-containing desulphurization flux showed almost similar desulphurization efficiency compared with those of commercially used desulphurization fluxes. It was even better than a typical lime/fluorspar mixed flux, which is now prohibited from being used in many companies due to its environmentally harmful character. It is emphasized that the desulfurization efficiency should be assessed under mechanical stirring in order to be used in the KR-type desulphurization process.

Kern, Wolfgang, Paul Wurth Italia S.p.A., Italy

Co-Author: Alessio Ferraris, Paul Wurth Italia S.p.A. • Fabio Cerutti, Paul Wurth Italia S.p.A. • Gabriel Korkmaz, Paul Wurth S.A.

Abstract: For many countries, steel production will rely for the foreseeable future, on the blast furnace route. There will be optimization processes taking place at the blast furnace, from PCI injection, coke rate reduction to Syngas injection to limit the carbon footprint. Nevertheless, availability of good quality coke at a reasonable price level will be required to ensure a stable operation of the Blast furnace in some regions for years to come. To produce good quality coke it is required to utilize high quality coking coals with excellent coking behavior to ensure a continuous and stable carbonization process through traditional top charged coke oven batteries. Due to the limited availability of good coking coals on the world market and the ever increasing cost for these coals, a trend can be seen with more and more coke producers changing from top charged coke oven battery operation to stamp charged coke oven battery operation in several parts of the world. When applying the stamp charging coke making process the selected coal blend will be compacted before charging into the coke oven. Such compacting will allow the coke producers to apply coals with less favorable carbonization behavior and still enable them to produce the desired high quality coke for the blast furnace operation at a lower cost. The stamp charging technology is particularly interesting in countries with large coal reserves, however the coals having lower or limited coking and carbonization characteristics. Through the introduction of the stamp charging process, these countries will be less dependent on the import of expensive coking coals. The paper will provide an overview on the coke making trends in several regions of the world.

Kesavan, Sailesh, Swerim AB, Sweden

Co-Author: Pooria Jalali, Swerim AB • Hyunjin Yang, Swerim AB • Pavel Ramirez Lopez, Swerim AB

Abstract: SWERIM’s numerical model for continuous caster has been developed over the last decade through numerous projects. The model can predict the caster behaviour at a level of detail that it replicates industrial caster i.e., digital twin. This digital twin model can be used to optimise caster performance without the risk associated with the plant trials. The manuscript describes the methodology used to study the heat transfer in the continuous casting mould with an intumescent coating. The numerical modelling process starts with compiling a database of caster layout, process data, steel grade, and slag composition etc. A 3D virtual geometry of the industrial caster is built with details such as the SEN, mould with cooling water channels and one strand length after the mould exit. The flow, heat transfer and solidification are solved using Fluent CFD software. The reference case was compared with industrial process data such as shell thickness and cooling water rate through blind tests for validation. The heat transfer coefficient (HTC) of the intumescent coating was obtained from characterisation. The HTC value was patched to the mould walls in the validated reference case and a parametric study based on possible operational window was carried out. The resulting data from the digital twin was used to provide guidelines on the operation range with the intumescent coating to obtain optimal solidification in the final product. Keywords: Heat transfer coefficient, intumescent, slab caster, digital twin, solidification.

Kharchenko, Oleksandr, Zaporizhzhia National University, Ukraine

Co-Author: Oleksiy Smirnov, National Academy of Sciences of Ukraine • Olena Volkova, Iron and Steel Institute, TU Bergakademie Freiberg

Abstract: The work is devoted to the analysis of physical and chemical processes in the high-temperature reaction zone (HTRZ), which is formed in steelmaking processes with oxygen blowing, such as converter production. Detailed thermodynamic analysis of HTRZ has been conducted, and parameters of liquid steel bath HTRZ have been determined: temperature, masses and chemical composition of metal, slag and gas phases. It is concluded that the carbon contained in the metal of HTRZ behaves as a catalyst for the transition of the iron into the gas phase and, accordingly, the irrevocable loss of iron in the steelmaking process. The results of the study allowed to build previously unknown fragments of equilibrium phase diagrams of the high-temperature region of systems "iron-oxygen" and «iron-oxygen-carbon». Another aspect of this study is removal of impurities from HTRZ. It is important process in which chemical elements are irretrievably removed from the space of the steelmaking unit. According to the temperature and the degree of removal into the gas phase, studied impurities can be divided into three groups: a) carbon, which is almost completely removed at a relatively low total oxygen content in the HTRZ and temperatures up to 2000°C; b) silicon, calcium, magnesium and phosphorus, which are almost completely removed into the gas phase in the temperature range of 2100...2800°C; c) manganese, sulfur, iron and aluminum, which are partially removed at temperatures above 2600°C. With an increase in the total oxygen content in the HTRZ above 15%, temperature increase sharply slows down, reaching limit of 2900°C at a total oxygen content of 20%. In this case, iron intensively escapes into the gas phase along with impurities. Therefore, blowing the steelmaking bath with oxygen at a very high rate is inappropriate, since it does not lead to a significant increase in the productivity of steelmaking unit.

Kim, Kyunghwan, Hanyang University, Korea, Republic of

Co-Author: Joohyun Park, Hanyang University

Abstract: One of the most effective ways to reduce carbon emissions in the oxygen steelmaking process is to lower the hot metal ratio (HMR) in basic oxygen furnace (BOF). However, if the HMR is lowered, the amount of oxygen blowing during decarburization in the BOF converter increases due to a lack of heat source. As a result, the amount of the deoxidizer increases because the end point oxygen content in the molten steel increases, which results in a deterioration of the cleanliness of molten steel. Therefore, this study was conducted to ensure the molten steel quality even at a decreased HMR about 10%p compared to the current level to reduce carbon emission in a BOF steelmaking. An appropriate amount of silicon in hot metal was presented to maintain the lowered HMR, and a method of refining phosphorus when the silicon content in hot metal is varied for the lowered HMR was presented. Finally, even if the amount of scrap usage increases due to the application of lowered HMR operation, a process was improved to resolve the tramp elements issue.

Kim, YongWoo, Chosun University, Korea, Republic of

Co-Author: Sun–Joong Kim, Chosun University

Abstract: The consumption amount of plastic has increased over the past. Generally, the waste plastics are landfilled or incinerated, which caused environmental problems. Waste polymers, whose main components are carbon and hydrogen, partially replace coke as a carbon source in the EAF process and have the potential for savings of electricity and carbon resources. It is necessary to effectively utilize the waste polymer as a reducing agent by comparing the various properties of waste polymer with those of pure plastics (PE, PP, and PS). In this study, the effect of waste polymers addition on the reduction behaviors of iron-containing by-products was conducted. In addition, the metallurgical properties of the pure polymers and waste polymer were investigated by FT-IR, DSC, and pyrolysis analysis for by-product gas during the reduction reaction.

Kim, Gibeom, Pohang University of Science and Technology, Korea, Republic of

Co-Author: Jinyoung Kim, Graduate Institute of Ferrous & Energy Materials Technology • Chang-Hee Yim, Graduate Institute of Ferrous & Energy Materials Technology • Woong-Hee Han, POSCO • Soo-Chang Kang, POSCO • Dae-Geun Hong, Graduate Institute of Ferrous & Energy Materials Technology

Abstract: In order to improve the efficiency of the decarburization reaction and control the ingredient of molten steel in the Ruhrstahl Heraeus (RH) degassing process, it is necessary to maintain an appropriate vacuum level and keep the refractory in contact with the molten steel clean. However, the temperature difference between the molten steel and refractories causes the steel skull and the solidified slag to adhere to the refractory, affecting the steel component deviation and steel product quality. Due to the absence of a quantitative measurement method for the present amount of steel skull in the RH process, it is difficult to establish an accurate relationship between operation variables affecting the precise element component control of molten steel. In addition, this leads to operation that relies on know-how of individual operator during the RH process. In this study, the quantitative measurement and its evaluation of the steel skull were conducted for improving the temperature control and adjustment of molten steel component during the RH operation. The amount of steel skull was estimated using cross-section images of vacuum vessel before and after the RH operation plant. The correlation between quantitative amount of steel skull and actual RH operation data including variables such as steel component, temperature and time was analyzed statistically technique machine learning. The steel skull amount as a dependent variable was categorized, and the machine learning modelling using the Random Forest (RF) and the Extra Tress (ET) algorithms was performed using approximately 620 data of RH operation. The obtained results have been discussed in context of the knowledge of steel making metallurgy. Physicochemical analysis about the change in the amount of steel skull and correlation between RH operation variables revealed the effectiveness of the proposed machine learning approach.

Kim, Ji Joon, POSCO, Korea, Republic of

Co-Author: Young-Wook Jun, AIcraft Inc. • Jong-Chul Kim, POSCO

Abstract: Reducing the slab width widening around the 400 series stainless steel is very necessary to improve the yield rate by reducing the amount of slab edge in the hot rolled coil. The amount of slab edge is multiple linear defects that occur within 20mm of both edges of the coil due to the widening of the slab narrow side during rough rolling of hot-rolling. In this study, a factory applied on-line model for the development of an artificial intelligence (AI)-based slab width prediction model is proposed. The proposed model collects operation data in units of 1 second during continuous casting and includes everything from the data preprocessing process to the learning and evaluation of the artificial intelligence model. A multilayer perceptron (MLP) model was used. The most important thing in the data pre-processing process is to align the working data by the position of the width of the slab. The developed width control model shows more than 95% of slab width prediction accuracy for both the learning data and the evaluation data. It is expected that the research model proposed in this study can be applied to the development of various predictive models with time series characteristics.

Kim, Taesung, Hyundai Steel Co., Korea, Republic of

Co-Author: Jooho Park, Hyundai Steel Co. • Dong Woon Kim, Hyundai Steel Co. • Geun Ho Park, Hyundai Steel Co. • Joo Hyun Park, Hanyang University

Abstract: The demands for the cleanliness of steel melts are increasing to improve the mechanical and physical properties of high Si & Al alloyed steels. In the present study, the effect of Si content of steel melts containing 1.5% Al as well as the addition sequence of Si and Al alloy on the characterization of non-metallic inclusions have been investigated. When Si (0.5-3.0%) was added to the melts at 1600°C, SiO2 inclusions were primarily formed and thereafter the area fraction of the inclusions decreased over time. Then, the addition of 1.5% Al to the steel melts containing 0.5-1.0% Si resulted in the formation of Al2O3 clusters due to the high driving force of the Al deoxidation, which is in consistent with the population density function (PDF) analysis with a lognormal distribution. On the other hand, singular type of Al2O3 inclusions were formed when 1.5% Al was added to the 3.0% Si melt because the driving force of the Al deoxidation was relatively low compared to that of Si deoxidation. The PDF analysis for the 3%Si-1.5%Al system showed a fractal distribution, which means that the inclusions are grown by collision mechanism. Alternatively, when 1.5% Al was preferentially added to steel melt, cluster-type Al2O3 inclusions were formed by the strong driving force of the Al deoxidation. The number of cluster-type Al2O3 inclusions decreased over time. When 3.0% Si was subsequently added to the 1.5%Al melt, the singular Al2O3 particles were mainly observed in the steel. Because the addition of Al results in the formation of Al2O3 inclusions in the melts regardless of the alloying sequence and Si content, it is important to float up and to separate the cluster-type Al2O3 inclusions to improve the cleanliness of the high Si & Al alloyed steels.

Kintscher, Björn , SMS group, Germany

Co-Author: Cosimo Cecere, SMS group • Tim Kleier, SMS group • Tristan Töpfer-Bergner, SMS group

Abstract: In view of global warming and the international agreements on climate targets, the topic of sustainability is more urgent than ever and the steel industry must make its contribution to CO2 reduction. At the same time, demand for "green" steel is increasing, as the automotive industry, for example, has to consider the CO2 footprint of their products over the entire life cycle. The CSP® technology has been known since its introduction as a particularly efficient way to produce high-quality hot strip. With its further development, CSP® is not only offering the energy-optimized way of hot rolled coil production, but is also continuously closing the gap of achievable products compared to the conventional route. Recent modernization upgrades of the CSP® plants revealed new improvements and benefits to increase productivity, improve plant reliability, reduce energy consumption and lower the carbon footprint. Even though modernizations are the most common approach in Europe, a new steel plant is built - and as such, it is a novelty since decades. In 2025, the first carbon-neutral CSP® Nexus plant will go on stream as part of the H2 Green Steel project in Northern Sweden. The CSP® Nexus technology does not only move forward in terms of energy optimization but even makes the big step into carbon free steel production. In addition, it takes full advantage of high throughput casting and the latest developments in hot rolling, such as endless operation where beneficial. Thus, CSP® Nexus increases and enhances the product mix compared to other combined casting and rolling plants in terms of steel grades and strip dimensions. This paper will give an overview on technology of the CSP® Nexus plant for H2 Green Steel and the possibilities of the Nexus concept. In addition, it will highlight the approach for the modernization of existing CSP® plants.

Kinzel, Peter , Paul Wurth S.A., Germany

Co-Author: Fernand Didelon, Paul Wurth S.A. • Miriam Valerius, Paul Wurth S.A. • Jihong Ji, Paul Wurth S.A.

Abstract: In view of the new economic reality, Paul Wurth has reassessed the existing integrated steel plant assets in the light of the European CO2 emission ambitions. Natural gas not being available in the short term and seeing the scarce scrap and high grade pellet availability after 2030, it will be of the essence for cost efficient European steel plants to count on a CO2 lean process for massive steel production based on the well established reduction melting process. Paul Wurth has in this respect come up with a concept allowing the easy substitution of the traditional blast furnace by a compact direct reduction and melting furnace. This new furnace, EASyMelt™ can be the key in existing steel plant set ups allowing highly cost efficient steel production as well as satisfying the net zero carbon target

Kirmse, Christoph , SMS group, Germany

Co-Author: Pallavi Mohta, SMS group • Ritwick Manatkar, SMS group • Agnieszka Zuber, Macrix Technology Group • Rashmi Murthy, SMS group

Abstract: During continuous casting longitudinal facial cracks (LFC) can occur due to various root causes. LFCs are difficult to capture during the production process and are visible only in the final stages of a process. Some of the LFCs can open and lead to a breakout. This creates safety and environmental issues due to hot, liquid metal flowing outside the casting machine. It also leads to a loss in production time and potential damage to the equipment. The goal of this paper is the prediction of those breakouts during operations using deep learning models. The deep learning algorithm uses different signals at the mold to calculate a probability of a breakout. When the probability exceeds a threshold value, a breakout alarm will be triggered. Upon detection of an upcoming breakout, suitable countermeasures are suggested to prevent the breakout from happening. Early results suggest a reduction of breakout events of 50%.

Kirschen, Marcus, RHI Magnesita, Germany

Co-Author: Uxia Dieguez, RHI Magnesita • Jan Lueckhoff, RHI Magnesita • Verena Schmidt, RHI Magnesita • Markus Gruber, RHI Magnesita

Abstract: The mandatory transformation of European steel production towards Green steel routes requires an increasing use of steel scrap and direct reduced iron. Consequently, new EAFs with large melt volumes are expected to meet the required production capacity at minimum CO2 intensity. With increasing melt volumes the impact of oxygen injectors to bath mixing decreases and additional stirring technologies are required for an optimum EAF process. Inert gas stirring is an established method to improve process control, energy efficiency, metal yield and melting time. In the following paper, the benefits of RHI Magnesita´s gas purging technology in EAFs are highlighted by means of transient CFD simulations; with special focus on the influence of the steel flow on refractory wear and hearth mix consumption. The observed process improvements are presented by industrial case studies covering EAFs fed by steel scrap, direct reduced iron and/or hot metal. The here shown process benefits are achieved at the same refractory consumption figures in contrast to competing EAF stirring technologies.

Kitagoh, Kazutoshi, Toshiba Mitsubishi-Electric Industrial Systems Corporation, Japan

Co-Author: Toshihito Shimotani, Toshiba Mitsubishi-Electric Industrial Systems Corporation • Masaki Nakaema, Toshiba Mitsubishi-Electric Industrial Systems Corporation • Min Zhang, Shougang Jingtang United Iron & Steel Co., Ltd. • Jixin Li, Shougang Jingtang United Iron & Steel Co., Ltd. • Zhankui Dong, Shougang Jingtang United Iron & Steel Co., Ltd.

Abstract: We introduce and discuss two technical features of hot rolling in an endless line with the excellent application results. The first feature is functionality to establish rolling stability with high quality of products in endless rolling. The second feature is automation to enable multiple rolling modes. In an endless line, continuous caster and rolling equipment are directly connected via a tunnel furnace. There is a shear between caster and tunnel furnace. The line can be operated in 3 modes – “endless“, “semi-endless“ and “coil to coil“ rolling. With endless rolling, there is no shear cut between caster and tunnel furnace. The advantage of endless rolling is that ultra-thin coils can be produced stably with high product quality since, unlike a conventional hot rolling, there is no loss of tension at head/tail end. With semi-endless rolling, the caster output is cut into long slabs. The coiler entry shear is used to create several coils from a single slab. With coil to coil rolling, the caster output is cut into slabs. The mill and caster can operate at different speeds in semi-endless and coil to coil rolling. When rolling speed needs to be changed to satisfy production or operational requirements, coil to coil or semi-endless rolling can be selected. The multiple rolling modes feature provides flexible selection of rolling mode on a single line and expands both product types and operational flexibility. Finally, we show excellent control results in the actual line with the above technical features.

Kleimt, Bernd, VDEh-Betriebsforschungsinstitut GmbH, Germany

Co-Author: Rajko Antonić, Minkon GmbH • Martin Schlautmann, VDEh-Betriebsforschungsinstitut GmbH • Izaskun Alonso Oña, Sidenor Investigación y Desarrollo • Hellai Abdullah, AG der Dillinger Hüttenwerke • Katharina Kortzak-Hojda, VDM Metals GmbH • Robin Jentner, AG der Dillinger Hüttenwerke • Torsten Lamp, Minkon GmbH • David Wappel, RHI Magnesita GmbH • Stefan Eder, RHI Magnesita GmbH • Gernot Hackl, RHI Magnesita GmbH

Abstract: The control of hydrogen content in steelmaking has always been an important issue, due to the severe quality problems which are caused by too high hydrogen contents in the final steel product. This leads to high demands regarding lowest hydrogen contents at the end of liquid steelmaking, which requires a vacuum degassing treatment of liquid steel and a tight control along the whole liquid steelmaking and casting process route. In the RFCS project HydroPick detailed and comprehensive investigations on all mechanisms of hydrogen pick-up and removal throughout the complete process route of liquid steelmaking and casting were performed. The results were used to derive dynamic process models for through process prediction of the hydrogen content evolution under different process conditions of the involved processes. Regarding the continuous casting process, new and innovative concepts for the tundish with respect to wear lining, preheating, cover powder and fluid flow control of liquid steel were developed, to understand the relevant influencing factors as well as to control and limit the hydrogen pick-up during the casting process. Also, a new system for continuous measurement of the hydrogen content dissolved in liquid steel was developed and applied for monitoring the hydrogen content evolution in the tundish during casting. Finally the predictive process models were used to build a through process on-line advisory system for monitoring and control of the hydrogen content evolution, in combination with new measurement strategies, for reliable and effective achievement of the target values. The hydrogen pick-up is predicted and as far as possible limited, and the process parameters of hydrogen removal during vacuum degassing are controlled, so that the quality-dependent hydrogen target values for liquid steelmaking can be reliably achieved. The investigations and developments were performed at the steel plants of Dillinger and Sidenor in cooperation with BFI, RHIM and Minkon.

Kleimt, Bernd, VDEh-Betriebsforschungsinstitut GmbH, Germany

Co-Author: Waldemar Krieger, VDEh-Betriebsforschungsinstitut GmbH • Diana Mier Vasallo, Sidenor Investigación y Desarrollo • Asier Arteaga Ayarza, Sidenor Investigación y Desarrollo • Inigo Unamuno Iriondo, Sidenor Aceros Especiales

Abstract: The Electric Arc Furnace (EAF) for scrap-based steelmaking will play an important role in near future to realise the transition towards Green Steel production due to its more efficient use of resources, lower carbon emissions and inherent circularity compared to the iron ore-based steelmaking. This work presents a practical approach for a Decision Support System for the EAF with real-time heat state monitoring and control setpoint optimization which has been developed within the EU funded project REVaMP and applied at the EAF of Sidenor in Basauri, Spain. The system consists of a dynamic process model based on energy and mass balances, including thermodynamic calculations for the most important metallurgical reactions like dephosphorisation and decarburisation, and a scrap characterization and scrap mix optimisation tool to estimate the scrap properties, which are critical for reliable process performance and accurate online process control. The underlying process models and control functions were validated on the basis of historical production and measurement data of a large number of heats produced at the Sidenor plant. Also, the applied model parameters were fitted using this data to further increase the prediction accuracy and to account for influences, e.g. during melting, that are otherwise difficult to model precisely. The model calculations are adapted in real-time to the performed measurements and analysis values to make best use of the information available during EAF heat production. Particular attention is paid to the modelling of the dephosphorisation reaction and the end-point control of the phosphorus content, as this is a critical parameter for production of high-quality steel grades along the EAF process route. The developed tools for Decision Support are integrated within a web application to facilitate their utilization and to provide impactful support for the plant engineers and operators.

Klitschke, Silke, Fraunhofer Institute for Mechanics of Materials , Germany

Co-Author: Andreas Trondl, Fraunhofer Institute for Mechanics of Materials • Florence Andrieux, Fraunhofer Institute for Mechanics of Materials • Dennis Revin, Fraunhofer Institute for Mechanics of Materials

Abstract: AHSS are widely used in crashrelevant components of automotive structures. Because of their low ductility an accurate failure prediction is mandatory for this class of materials. Hence, in the past different complex failure models have been developed. The calibration of those failure models is usually based on experiments with defined stress states, partly at different strain rates. Though, there is still a lack of suitable experiments for the validation of those calibrated failure models from quasi-static up to crash relevant strain rates cover-ing different complex loading situations. These validation experiments should be suitable for a wide range of test speeds, lead to nearly plane stress states from compression/shear to multiaxial tension and should show characteristic damage. In this contribution experimental validation concepts were developed and applied to a DP1000 steel sheet and a ZStE 340 steel sheet. These validation experiments are appropriate for quasi-static and highspeed testing. The key of these validation tests is to develop specimens with different potential critical areas. De-pending on the failure behavior of the material, failure occurs in the shear or in the nearly plane strain re-gion. Especially the safety-critical negative strain rate effect concerning the shear failure strain of advanced high strength steel sheets can be validated by the proposed new material dependent shear-tensile validation test. The specimen geometries are designed depending on the ductility of the material and the manufactur-ing is performed without any joining procedure. Local failure initiation on the surface of the specimens is observed by highspeed video recording and verified by FE-simulations. With these experimental concepts the validation procedure of failure models can be performed cost-efficient and reliable over a wide range of stress states and strain rates. This leads to an improvement in failure prediction and utilization of the light-weight construction potential of AHSS sheets in automotive applications.

Klut, Peter, Danieli Corus B.V, Netherlands

Abstract: Dry blast furnace gas cleaning technology offers great economic advantages when compared to traditional wet gas cleaning owing to its improved energy efficiency, lower cost, reduced plot space, and practically eliminated water consumption. Given the improved operational economics and – in some areas – the physical or economic scarcity of water, steel producers are shifting towards the application of blast furnace gas cleaning systems, in which the wet scrubber is replaced with a dry second gas treatment stage. The Danieli Corus solution is based upon proven technology that has been applied numerous times for cleaning aluminium smelter gases and anode baking fumes. The system consists of a gas conditioning tower, reagent injection system and (pressurized) filter modules with low pressure pulse cleaning. Currently, Danieli Corus is implementing this technology for three greenfield blast furnaces in India. This article presents the advantages of the proven technology as well as some improvements that will be applied during the ongoing projects. These improvements include steam reheat of (cold) blast furnace gas, single phase water injection in the conditioning tower and two stage countercurrent absorbent injection.

Knepper, Marco, Hüttenwerke Krupp Mannesmann GmbH, Germany

Co-Author: Torsten Müller, Primetals Technologies Germany • Willi Bühler, Primetals Technologies Germany • Wolfgang Brett, Primetals Technologies Germany • Sebastian Schäfer, Hüttenwerke Krupp Mannesmann GmbH

Abstract: "A high degree of automation combined with a respective safety standard, reliable and user-friendly operation and a compact design are the requirements for modern ladle furnaces to be implemented in existing converter plants and steel mills. Primetals Technologies has successfully implemented its proven ladle furnace technology in combination with complex and high customer requirements with limited space availability at the HKM converter plant in Duisburg. In HKM, the entire production line is operated and monitored from a central control room. For this reason, all necessary work and functions must be controlled and supervised remotely, such as temperature and sampling, ladle stirring, etc. The ladle furnace is equipped with state of the art camera systems, robotics, automatic stirring gas coupling and a semi-automatic quick exchange for stirring gas lances to reduce manual tasks to a minimum. These complex automation processes require proven sensor technology to ensure a high level of operational reliability in the harsh environment of a steelplant as well as a holistic approach to combining different automated functions. Both individual components and combined automated processes of several plant parts, including the sensors used, are presented. Remaining user activities are explained, and security-related topics such as access to restricted areas and monitoring of the facility are described. Finally, the experience and operational results after more than 2 years of operation are presented to show the impact of the integration of a ladle furnace into an existing BOF meltshop in regards to the metallurgical impact and consumptions."

Koch, Bernd, Matplus GmbH, Germany

Co-Author: Alex Miron, Matplus GmbH • Igor Alperovich, Matplus GmbH

Abstract: For structural applications, steel already has the best overall recycling rate of all materials - however, steel for structural components, automotive chassis and bodywork is today largely produced via the classic blast furnace route, which is still associated with high CO2 emissions for the foreseeable future. A key aspect in reducing the overall life cycle balance is the step towards the "circular economy", in which largely complete recycling is to be achieved. To this end, a holistic view of the production, usage and end-of-life processes is required. For steelmaking this task is faced with a “scale” issue – the actual processes are highly sophisticated and detailed down to atomistic chemical reaction scale, but the overarching material and energy flows are in the kiloton / GWh regime. While for both extremes process and simulation tools are available – classical LCA for the macroscale for instance – a universal modelling tool is missing, which bridges between the detail of process simulation and measurement and the macroflows, allowing to balance all efforts and outputs in a mathematically sound and cohesive manner. In this paper an innovative approach is presented, integrating well-established flow analysis methodology in a state-of-the-art materials knowledge system. Concrete approaches for mapping and modelling EAF steelmaking processes in terms of material and energy flows from input scraps to steel and recyclate output are presented, and concepts for bridging the scale gap are developed. Finally, the vision of a universal communication platform based on this model and data structure for all concerned parties, from waste managers over steelmakers to producers, is established.

Kofler, Alexander , SMS group, Germany

Co-Author: Klaus Pronold, SMS group • Christian Mengel, SMS group • Guido Eichert, EMG Automation GmbH

Abstract: The target of the centerline control is to eliminate the need of manual interventions for steering of the hot strip in a finishing mill. The new system works based on the highly accurate and reliable HotCAM measuring system. It measures the lateral hot strip position between the finishing mill stands. The highly sophisticated steering control philosophy will be explained. Further, we present first results on improved head, body and tail rolling stability, productivity increase, impact on reduced work roll damages and therefore unexpected roll changes and improved strip surface defects of this latest installation. The results will show a tremendous improvement by this technology. These results will be presented as well as future steps to ultimately eliminate permanent human interventions for hot sheet rolling paving the path towards lights-out operation.

Koldorf, Sebastian , MAGMA Gießereitechnologie GmbH, Germany

Co-Author: Erik Hepp, MAGMA Gießereitechnologie GmbH • Evgenii Shvydkii, MAGMA Gießereitechnologie GmbH

Abstract: Today, simulations for improving process conditions and the quality of continuous cast products are a generally accepted tool. State of the art simulation tools provide quantitative insights into the flow, solidification and stress formation in continuous casting processes. This includes the entire casting process, starting from the tundish and the flow into the mold, up to the solidifying strand, that is withdrawn through various cooling zones. This provides important information about quality and productivity when evaluating process alternatives. The classical use of simulation solutions has evolved to a higher degree of automation and virtual process optimization. Usage of digital twin technology in combination with integrated statistical tools enables a systematic virtual testing to identify an ideal process window. This enables the expert to identify the significant process parameters and to investigate the level of their influencing effect, without performing expensive and time-consuming trials on the shop floor. Based on this knowledge, it is possible to optimize continuous casting processes that are both, cost-effective and robust with respect to process variations. This paper will discuss the modelling of modelling of electromagnetic stirring (EMS) and its impact on the flow behavior in the strand. Another focus will be the evaluation integrated stress calculation to avoid the formation of cracks. Stress simulation is also used to described the gap formation in the mold and the corresponding change of primary cooling conditions. The results are shown using industrial examples for a bloom caster. With the availability of the integrated process knowledge of a digital twin, it is possible to identify optimal operating points for quality improvements and productivity increases. The objective is to derive a comprehensive model for online monitoring and optimized dynamic online control of the cooling and solidification process. KEYWORDS: VIRTUAL EXPERIMENTATION –CONTINUOUS CASTING –DIGITAL TWIN –ONLINE CONTROL –ELECTROMAGNETIC STIRRING

Kon, Tatsuya, Kyushu University, Japan

Co-Author: Ginichiro Sato, Kyushu University • Ko-ichiro Ohno, Kyushu University

Abstract: In Japan, ironmaking using blast furnaces is the mainstream, and sintered ore is mainly used as an iron source. Sintered ore is made by sintering the granulated powdery iron ore. The strength of granulates in the sintering process is one of the important factors to improve the gas permeability of sinter bed. In high permeability, productivity of the sintering process increases. In recent years, high-grade iron ore has been depleting, and the usage of low-grade iron ore containing a large amount of gangue mineral such as silica and alumina is increasing. It is expected that the increased gangue mineral affects the strength of the granulate. The purpose of this study is to investigate effect of gangue mineral existence distribution in iron ore particles on the compressive strength of the granules. To evaluate the effect of gangue, coarse and fine powders were prepared by hematite ore containing gangue and pure hematite reagent and 4 types of granulates were prepared as combinations fine/coarse and ore/reagent powders. Theses granulates were produced by wet granulation using a tire type pelletizer. Wet and dry compression strength of granulates were measured by compression tester. From the experimental results, wet compression strengths of granules were similar value and independent of gangue distribution. It is considered that the adhesion force by liquid bridge is dominant in the wet compression strength. On the other hands, the granulates with gangue mineral in fine iron ore powders showed stronger dry compression strengths than other granulates. It is considered the effect of Coulomb force due to electric surface potential difference of hematite and gangue minerals.

Korkmaz, Gabriel , Paul Wurth S.A., Luxembourg

Co-Author: Mathias Hoffmann, Paul Wurth S.A. • Wolfgang Kern, Paul Wurth Italia S.p.A.

Abstract: Decarbonization route for most steelmakers is already described for the next decades. However, the remaining operation time of the existing coke oven plants will be a challenging task for the coke producers. The more and more stringent requirements of local and national authorities force the coke producers to continuously update the operation and equipment. In light of this situation various technologies have been developed to support the coke producers in order to meet the environmental requirements. Environment and safety aspects are to be respected and therefore it is necessary to keep attention on typical areas of coke oven plants to ensure a continuous and safe plant operation. Several new technologies have been developed over the last years and proven to be very effective in order to fulfil the requirements with regards to environmental protection. This paper will highlight the areas of concern in the different sections of a coke oven plant: from the coke oven battery, moving machines and by-product plant. Moreover, it will demonstrate effective solutions as upgrades or adjustments implemented in various coke oven plants all over the world to ensure the environmental protection performance. These technologies can be applied for new coke oven plants and for modernization of existing coke oven plants.

Köster, Marc, VDEh-Betriebsforschungsinstitut GmbH, Germany

Co-Author: Piero Frittella, Feralpi Group • Jörg Bellmann, ESF Elbe Stahlwerke Feralpi GmbH • Ralf Schuster, ESF Elbe Stahlwerke Feralpi GmbH • Matthias Groll, ESF Elbe Stahlwerke Feralpi GmbH • Waldemar Krieger, VDEh-Betriebsforschungsinstitut GmbH • Martin Schlautmann, VDEh-Betriebsforschungsinstitut GmbH

Abstract: For the first time, a laser vibrometer system in combination with appropriate artificial intelligence methods for clustering of the measured vibration spectra has been tested at a continuous casting machine to receive information on the solidification status of the strand. Measurements with the laser vibrometer at a fixed strand position of the billet caster of ESF under conditions of incrementally increasing casting speeds revealed a transition in the population of the identified vibration clusters as a footprint of the passed crater end position with a change from a fully solidified strand to a strand with some liquid core at the measurement position. This was in accordance with the results from a three-dimensional dynamic temperature and solidification model which has been set up based on a state-of-the-art approach for solution of the heat flow equation with tailored sub-models for the different boundary zones of the ESF billet caster (i.e., mould, secondary spray water zones and radiation zones) and installed at the steel plant for online monitoring and control of the casting process. The application of the newly installed measurement and model-based information systems at ESF revealed significant improvements of their billet casting process in terms of reduced strand breakout rates and increased productivity.

Koubek, Christian, Primetals Technologies Austria, Austria

Co-Author: Richard Krump, Primetals Technologies Austria • Christoph Sedivy, Primetals Technologies Austria

Abstract: "Melting steel has always been a challenging process. There has been a lot of development in automating this process in the past decades. However, most EAF steel is still produced using static melting profiles. Those profiles treat all the heats the same and are ignoring regular fluctuations. Fluctuations come from charged material eg scrap quality, alloying material, DRI/HBI quality as well as stability of electrical supply. Both have influence on the production results. For example, deviation in scrap or DRI/HBI quality or variation in primary voltage from the grid. The next level of process control is monitoring these variations and their impacts and applying countermeasures for process optimization and minimizing energy consumption. Sophisticated electrode control systems already have a huge amount of information, but typically this has not been used for process improvement. Recent developments combining the information already available are providing intelligent process derived strategies bringing a new level of process optimization. Integrating these improvements into the electrode control system enables the precise control of the electrical and chemical power input according to the current process needs. As a result, the fluctuations of the consumption figures and power on times will be minimized leading to greater production efficiency and reduced costs. The idea and implementation of such strategies as well as results achieved will be shown in this paper. "

Krassnig, Hans Jörg, Primetals Technologies Austria, Austria

Co-Author: Ali Hegazy, Primetals Technologies Germany • Miao Peng Sheng, Primetals Technologies China Ltd. • Michel Hein, Primetals Technologies Germany • Jörg Schwörer, Primetals Technologies Germany • Hagen Fuchs, Primetals Technologies Germany

Abstract: "Today’s steel producers face immense challenges when working with an EAF. These challenges may include anticipating tomorrow’s more stringent environmental targets for green steel, achieving optimal energy efficiency, dealing with the constraints of weak electrical infrastructure, and operating a closed-roof EAF while attempting to maintain the highest degree of productivity with modest OPEX and CAPEX. The EAF Quantum from Primetals Technologies is a proven solution for these complex challenges. The EAF Quantum is the latest energy-efficient EAF technology, yet quickly becoming well-established and growing fast. Since its first introduction, 11 references are now successfully in operation. This presentation will describe the EAF Quantum process and provide an overview of the technology and design concept. Features of the lmost recent 2x150-t EAF Quantum for Tosyali in Turkey (start-up in Y2023), currently under erection, will be highlighted. Moreover, the real-world operational results of the 11 EAF Quantums will be presented, including project execution, productivity, and consumption figures. An outlook of the next-generation EAF Quantum (200-300t) will be briefly shared."

Krause, Fabian , SMS group, Germany

Co-Author: Andreas Kemminger, SMS group • Hans-Jürgen Odenthal, SMS group • Johannes Wilkomm, RWTH Aachen University • Johannes Henrich Schleifenbaum, RWTH Aachen University • Christian Goßrau, RWTH Aachen University • Manfred Wirsum, RWTH Aachen University • Florence Cameron, RWTH Aachen University • Huanhuan Xu, RWTH Aachen University • Heinz Pitsch, RWTH Aachen University

Abstract: Electric steelmaking using scrap generates 80% less greenhouse gases than the blast furnace route. The electric arc furnace (EAF) is usually equipped with natural gas (NG) burners that melt down the scrap and decarburize the melt. Many activities are underway to replace NG, at least to a large extent, with hydrogen. Hydrogen has complex combustion properties, e.g. high burning velocity, low ignition energy, low volumetric energy density, and wide flammability limits, which places high demands on the burner design. Here, additively manufactured (AM) burners open up new avenues with regard to the gas/water routing, and thus show significant advantages over conventional burners when using hydrogen. These avenues are being explored within the HyInnoBurn project. This project is part of the German Clusters4Future initiative (supported by the German Federal Ministry of Education and Research, BMBF) with partners from the entire hydrogen value chain and focuses on the development of additively manufactured burners for flexible use of NG and hydrogen. The presentation gives an overview of Computational Fluid Dynamics (CFD) simulations, manufacturing approaches and experiments at small-scale 50 kW and 450 kW burners. All burners are additively manufactured with a new and pure copper powder. High resolution combustion simulations show the fundamental flame structure, temperature and species distribution as well as the influence of increasing hydrogen amounts. While the 50 kW burner is examined with advanced laser diagnostics, the 450 kW burner is tested in an industrial sized furnace at the Gas- und Wärme-Institut (GWI) Essen. Difficulties and possible solutions for the change from NG to hydrogen are discussed.

Krauthäuser, Horst, IMS Messsysteme GmbH, Germany

Co-Author: Tobias Terlau, IMS Messsysteme GmbH • Lennart Möller, IMS Messsysteme GmbH • Cornelia Ionescu, Tata Steel Ltd • Frenk van den Berg, Tata Steel Ltd • Danique Fintelman, Tata Steel Ltd • Stefan Melzer, Tata Steel Ltd • Ernesto Montagna, SEGAL • Alexandre Lhoest, Drever International sa • Amedeo Di Giovanni, Drever International sa • Ulrich Sommers, SMS group • Christoph von der Heide, SMS group

Abstract: High energy cost and increasing requirements on the mechanical properties of modern steel causes high demand for sophisticated process control in the heat treatment of the flat steel production. X-ray diffraction is a technology, which is traditionally used in the laboratory but recently also as online measuring device in steel production. The X-ray Controlled Annealing Process (X-CAP®) uses the measured phase fraction in front of the rapid cooling for production of AHSS. The change from temperature control to the direct material control improves the production yield, increases the flexibility in the production and reduces the energy cost. Still there are more opportunities for this new technology, like the retained austenite measurement after the rapid cooling. Furthermore, the usage of higher X-ray energies extends the thickness range of the measurement and allows the phase fraction measurement in hot strip mills .

Kreso, Mark, EMG Automation GmbH, Germany

Co-Author: Timo Gemmer, EMG Automation GmbH • Jens Bublitz, EMG Automation GmbH

Abstract: Electrical sheets - along with magnets and lacquered copper wires - are key components for the manufacturing of electric drives. The projected growth of e-mobility will increase the demand for electrical sheets for the automotive industry from 100 thousand tonnes in 2018 to about 1.2 million tonnes in 2030. Quality assurance and the control of quality costs for electrical sheets thus determine the profitability of motor manufacturers to a large extent. The thickness and homogeneity of the insulating coating play a special role here. Beta transmission, used until now to determine mass per unit area, thickness, and density, will soon reach the limit of its availability. Different isotopes (krypton, strontium, promethium) are used for different weight ranges, but Promethium can only be purchased for the next 1 - 2 years. The EMG SOLID® systems, so far used for the quantitative determination of lubricant layers on sheet metal, offer an ideal replacement. Especially laser-induced fluorescence (LIF) can be used to reliably determine the desired measuring data online. The system parameters, e.g., laser excitation and observation wavelength of the fluorescence, detector sensitivity or signal timing are specifically adjusted to guarantee an optimal system adaptation to the respective type of coating. An additional reference measurement on uncoated sheet surfaces, e.g., by a suitable backscatter method, represents a further possibility for optimising this application. Coating thicknesses between 0 - 7 µm (incl. dark pigmented coatings) could be successfully determined. The methods are designed for inline or online measurement operation, also in traversing mode with typical travel speeds of up to 1 m/s. The EMG results clearly show that quantitative detection of insulating varnishes on electrical sheet in the micrometre layer thickness range is reliable possible. This paper describes the technological background of the method and shows laboratory as well as first application results.

Krieg, Elmar, SMS group, Germany

Co-Author: Wolfgang Scheffel, SMS group

Abstract: Over the recent years, Jumbo Beam and Section Mills were newly built, modernized and successfully commissioned or are under construction. Such heavy rolling mills require special technologies and equipment like thermo-mechanical rolling as well as in-line water quenching. Furthermore, rolling of beams up to more than a ton per meter poses special requirements on the rolling mill equipment design and layout. In particular, solutions for covering a very wide range of product program will be introduced. Beside the introduction of the mill equipment and its technologies, the paper will focus on the today’s and tomorrow’s possibilities to provide digital solutions for process and quality optimization, data and energy management, lifecycle and predictive maintenance strategies. We will demonstrate how AI can be utilized to achieve prescriptive maintenance with significant operational cost improvements.

Krull, Hans-Günter, Deutsche Edelstahlwerke Specialty Steel GmbH & Co. KG, Germany

Co-Author: Philipp Niederhofer, Deutsche Edelstahlwerke Specialty Steel GmbH & Co. KG • Frank van Soest, Deutsche Edelstahlwerke Specialty Steel GmbH & Co. KG • Svenja Richert, Deutsche Edelstahlwerke Specialty Steel GmbH & Co. KG

Abstract: Usually tool steels are used in quenched and tempered condition. Due to the phase transition from austenite to martensite and the volume change during the transformation controlling of distortion might be a challenge. The end user demands for high hardness of the final tool leads to a poor machinability. Engineering steels with bainitic structure are generally based due to economic reasons on a low alloying content, especially the carbon contend is rather low compared to tool steels. Bainitic steels require often a controlled cooling to get the desired micro structure and the maximum size to achieve a fully homogeneous bainitic structure is limited to dimension far below acceptable dimension of tool steels. A new developed steel with focusing on a bainitic structure even for bigger dimensions shows a lower hardness at ambient temperature then conventional hot-working tool steels but with a lower temperature dependency. Therefor at service temperature the mechanical properties are comparable to established grades. Heat treatment is simplified by a simple austenitization and cooling process without special requirement on the cooling rate. Due to a generally lower cooling rate and lower hardness compared to a Q&T process the risk of cracking is reduced. The abcence of a quench and tempering process in combination with low hardness at ambiant temperature whats good for machining leads a low CO2 foodprint of the process chain. With the combination of good weldability and rather low hardness after rapid cooling this grade can also processed in additive manufacturing and is well suited for a hybrid process of conventional and additive manufacturing.

Krull, Hans-Günter, Deutsche Edelstahlwerke Specialty Steel GmbH & Co. KG, Germany

Co-Author: Jamila Adem, Ugitech SA • Frank van Soest, Deutsche Edelstahlwerke Specialty Steel GmbH & Co. KG • Clara Herrera, Deutsche Edelstahlwerke Specialty Steel GmbH & Co. KG

Abstract: The number of steel grades used for high pressure componentsis in a hydrogen environment is very limited. The effect on Hydrogen on the mechanical properties of steels are shown. An overview of the RRA values (relative reduction of area) of stainless and engineering steel grades will be presented and recomandation for grades regading cost and mechanical properties are given.

Kügel, Manfred, SAS Institute Software GmbH , Austria

Abstract: This paper presents a method for minimizing the formation of cobbles in hot strip mills using data analytics, which was successfully implemented and proven in real-life production. The paper provides learnings from the implementation of this use case. Cobbles can cause significant damage, safety issues and production delays, resulting in financial losses. By analyzing data from various sources, patterns and trends in the production process that lead to cobbles can be identified. Using this information, real-time recommendations are provided to the process engineers and operators, who can then make adjustments to the process to prevent the formation of cobbles and improve overall efficiency. The results of the data analysis, implementation of preventative measures, and the real-life production are discussed, showing a reduction in the occurrence of cobbles and an improvement in overall efficiency. The paper concludes by providing valuable insights and learnings that can be applied to similar use cases, and how the use of data analytics, coupled with real-time recommendations, is a powerful and effective tool for identifying and mitigating the causes of production issues in hot strip mills.

Kühne, Ronny, RWTH Aachen University, Germany

Co-Author: Helen Bartsch, RWTH Aachen University • Markus Feldmann, RWTH Aachen University

Abstract: Scope of this research is the fatigue resistance of additively manufactured steel plates with galvanized surfaces. First the manufacturing process via wire arc additive manufacturing (WAAM) and hot dip galvanizing (HDG) of the specimens is described. In order to determine the influence of HDG on the fatigue resistance next to fatigue tests itself investigations on the surface roughness, the condition of the zinc layer and quasi-static tension on galvanized and ungalvanized specimens are pointed out. Even though, statistically no influence of the zinc coating on the surface roughness has been obtained, the zinc coating influences the surface shape in local areas leading to a reduction in the fatigue resistance due to the unidirectional dentritic growth of the Zn-Fe phase.

Kumagai, Ryouta, JP Steel Plantech Co., Japan

Co-Author: Ryuta Kumagai, JP Steel Plantech Co. • Keizo Abe, JP Steel Plantech Co.

Abstract: Recent metal plate and/or sheet, including ultra-high-strength steel for automobiles, are remarkably becoming high-performance (high-end). These materials tend to be conducted special treatment such as heat treatment which has not been performed in the past in the production process, and their flatness tends to be deteriorated. Consequently, the flattening ability of high-performance (high-end) metal plate/sheet, especially ultra-high-strength steel, has been insufficient in conventional leveling facilities, and more powerful and more accurate flattening facilities have been required. In response to this requirement, a new type hybrid roller/tension leveler and slitter combination facility (super hybrid leveler/slitter line), which has both tension leveler function and roller leveler function capable of handling a wide range of metal plate/sheet, was developed and put into the commercial operation. This document introduces the technology and outline of the new facility.

Kumar, Pratyush, M. N. Dastur & Co., India

Co-Author: Arnab Adak, M. N. Dastur & Co. • Atanu Mukherjee, Dastur Energy Inc. • Saptarshi Bhattacharya, M. N. Dastur & Co. • Soukarsa Das, M. N. Dastur & Co. • Arunava Maity, M. N. Dastur & Co. • Kaushal Kumar Sinha, M. N. Dastur & Co.

Abstract: Currently approximately two billion tons of steel are produced annually. The rapid industrialisation of developing nations has contributed to an addition of nearly one billion tons steel capacity over the past 20 years. CO2-intensive BF-BOF has been the preferred process method due to its scale, robustness, and feed flexibility. The potential to instantly replace BF-BOF with clean technologies like H2-based DRI or scrap-based EAF is constrained by the maturity of the technology, the economic impact of stranded assets, and the availability of resources (scrap & green H2) at the right quantity and price. Over the last decade, significant consolidation has happened in the steel industry, enabling steel businesses to optimize and reconfigure plant assets in order to achieve sustainable and effective production. Our work demonstrates that replacement of old inefficient BFs with DRI plants fueled by waste gas or syngas can be the most effective near-term decarbonization strategy for steel plants having multiple BFs and/or having facilities at multiple locations. Our case demonstrates how the use of HBI in BF can reduce CO2 emissions by about 1.5 mtpa while maintaining the same level of crude steel production in a large (around 10 mtpa) BF-BOF-based integrated steel plant. The BF productivity would rise by about 10% with an increase of 140 kg/thm HBI, helping to shut down two smaller inefficient blast furnaces. With the reduction of the coke rate by at least 45 kg/thm and around 140 kg/thm HBI addition in burden, the older smaller sinter & coke oven plant could also be decommissioned. Procuring power from renewable sources or a greener grid will reduce the usage of gas in inefficient power plants operation. Available gas has been considered for DRI plant operation. Other options for fueling DRI plants like syngas from waste and/or biomass gasification will also be further evaluated.

Kuthe, Sudhanshu, KTH Royal Institute of Technology, Sweden

Co-Author: Andrey Karasev, KTH Royal Institute of Technology • Rössler Roman, voestalpine Stahl GmbH • Izaskun Alonso Oña, Sidenor Investigación y Desarrollo • Björn Glaser, KTH Royal Institute of Technology

Abstract: Considering the advantage of achieving rapid and efficient process control with artificial intelligence (AI), the use of applied data-driven strategies is in demand among today's steelmakers. One important application is the online optimization of material additions during ladle refining. As every steel grade is unique, developing distinctly trained machine learning (ML) models seem significantly demanding. A data-centric ML approach can solve this problem by focusing on what AI systems must learn from unique datasets generated by specific steel grade production. Moreover, such data-driven process models may be simpler to integrate into existing production servers compare to the physics-driven models. In the proposed work, an operator-assisted decision support system (DSS) was developed using applied data-centric ML to optimize calcium additions required for producing ultra-clean low alloyed calcium-treated steels. Real industrial process parameters were collected before and after calcium additions for three steel grades. The collected process data were examined to design a base algorithm by continuously monitoring the characteristics of non-metallic inclusions at various stages of ladle refining. The predictive result obtained using the proposed DSS, and the response obtained from the actual process were compared and verified for each studied steel grade. Special efforts were taken to generate self-adapting output for each produced "heat" of a specific steel grade to avoid any degradation in predictive performance. The optimizer named "ClogCalc" was introduced based on the programming architecture of DSS for utilization and integration inside the industrial environment. Initial attempts were made to deploy this novel optimizer inside the production environment. The authors believe that this proposed approach could support operators in making dynamic decisions to optimize calcium additions. Keywords: Artificial intelligence, Industry 4.0, Online-monitoring, Steelmaking, Machine learning

Kwon, Jaehong, Hyundai Steel Co. , Korea, Republic of

Co-Author: Han sang Oh, Hyundai Steel Co. • Jong hyup Lee, Hyundai Steel Co. • Ga Eon Kim, Hyundai Steel Co. • Yu bin Lee, Hyundai Steel Co. • Byong Chul Kim, Hyundai Steel Co.

Abstract: Carbon dioxide emission reduction in the steelmaking process has been raised as an important issue according to greenhouse gas emission regulations. Among them, the use of biomass resources, which are carbon-neutral materials, is expected as a way to solve environmental problems. Therefore, a study was conducted to utilize biomass in a blast furnace by replacing coke and pulverized coal. First, the basic properties of 10 candidate groups were investigated to evaluate the feasibility of using biomass in a blast furnace, and the biomass for utilize in a blast furnace was selected in consideration of the calorific value and energy density. Iron-Bearing Biomass Coke (IBC), produced by mixing coal, torrefied biomass and iron ore, was used to partially replace coke with biomass. Evaluation for strength and reactivity must be preceded for the input of IBC in a blast furnace. Therefore, Shatter Index (SI) and Coke Reactivity Index (CRI) were evaluated, and the upper area of the blast furnace was simulated using the Shaft Inner-reaction Simulator (SIS). In addition, the combustion characteristics according to the mixing ratio of pulverized coal and biomass were investigated in order to partially replace pulverized coal with biomass. The combustibility of biomass was evaluated by a combustion test using a Drop Tube Furnace (DTF). The effect of using biomass in the blast furnace was investigated, and the following conclusions were drawn. When coke and pulverized coal are partially replaced with biomass, gas utilization and combustibility are improved. As a result, it is possible to reduce greenhouse gases emitted from the blast furnace through the use of biomass.

Ladenthin, Noel, RWTH Aachen University , Germany

Co-Author: Dieter Senk, RWTH Aachen University • Rongrong Wang, RWTH Aachen University • Hannes Drippe, RWTH Aachen University • Alexander Babich, RWTH Aachen University

Abstract: In order to reduce CO2 emissions and make steel production more sustainable, many steel producers are currently planning to produce metallic iron for steel production using hydrogen-based direct reduction instead of carbon based reduction gas. Melting in electric arc furnaces demands low amounts of gangue in DRI to keep the slag volume low. In respect to this DR pellets with high iron concentration are required. On the other hand highly concentrated iron ore with increased basicity is less available compared to medium iron containing BF pellets with low basicity. IEHK at RWTH Aachen University is characterizing different BF-grade pellets and investigating the influence of texture on reducibility using hydrogen. The characterization is carried out with the aid of chemical analyses of the composition and investigations of the microstructure by microscopy. The reducibility of individual BF-grade pellets is studied in a laboratory furnace using different hydrogen concentrations. In addition, direct reduction tests were carried out using a test plant with a capacity of approx. 20 kg of iron ore pellets. This allows the consideration of mechanisms that may be observed in the reduction of a bulk but not in individual pellets and allows use for upscaling considerations. The results of the investigation can be applied to design further direct reduction processes with low-grade iron ore pellets.

Laforest, Guylaine, Corem, Canada

Co-Author: Mathieu Dubé, Corem

Abstract: The global context of action against climate change brought the iron ore producers and steelmakers to engage in ambitious plan for GHG reduction. The direct reduction process is part of numerous steelmaker’s GHG reduction plans consequently this topic is increasingly studied - especially cases where green hydrogen would be used. To ensure that various iron ore products will be performing adequately in either typical or future alternative DR reduction processes, a test evaluating readily their quality, under industrial representative conditions, should be available. This paper presents an updated laboratory scale test method allowing to study direct reduction of iron ore products under conditions close to industrial scale. The updated test allows the use of simulations as input conditions, is non-isothermal, allows for changes in gas concentrations and includes less typical species such as water vapor and CH4. The updated test method follows the impact of direct reduction on pellet performance such as reducibility, metallization, fines generation, pellet deformation, clustering, microstructure, and carbon pick-up.

Lahdo, Rabi, Laser Zentrum Hannover e.V., Germany

Co-Author: Stefan Kaierle, Laser Zentrum Hannover e.V. • Frank Riedel, Fraunhofer Institute for Machine Tools and Forming Technology • Markus Puschmann, Fraunhofer Institute for Machine Tools and Forming Technology • Patrick Urbanek, Fraunhofer Institute for Machine Tools and Forming Technology • Jörg Hermsdorf, Laser Zentrum Hannover e.V. • Sarah Nothdurft, Laser Zentrum Hannover e.V.

Abstract: Duplex stainless steels are utilized for many applications in oil, gas and hydrogen industry due to their excellent properties regarding strength, toughness and corrosion resistance. This outstanding performance is realized owing to a two-phase micro-structure of ferrite and austenite with a portion of at least of 30 % austenite. During welding, this microstructure ratio can be lost because of unfavorable heat input. Arc welding processes have become established in practice for welding duplex steels. These welding processes can produce joints with the required microstructure ratio, but the productivity is low. Beam welding processes exhibit high productivity, however cannot produce welded joints with the required microstructure ratio. Laser beam-submerged arc hybrid welding combines the advantages of both welding processes and can be a good alternative with high productivity. In this study, laser beam-submerged arc hybrid welding processes are developed for butt joints of duplex stainless steel S31803 with different thicknesses of 16 mm, 20 mm and 30 mm using a disc laser beam source with a max. output power of PL = 16 kW. In this context, the parameters laser beam power, welding speed, wobble amplitude and the edge preparation are investigated to achieve a good weld appearance, 30 % austenite content and an impact energy of at least of 40 J at a test temperature of −40 °C. By means of visual inspections, metallographic analysis and Charpy impact tests, it can be proven that the weld seams meet these requirements. As results, efficient high-performance welding processes with welding speeds of up to vS = 1.0 m/min are achievable. Based on these results, laser beam-submerged arc hybrid welding has been shown to be a welding method with high productivity, which can play an important role in the future for the welding production of duplex steel parts.

Lamm, Rolf, Minteq International GmbH, Germany

Abstract: Continuous changes in the economic environment and the increasing number of EAF plants accompanied by competitive pressure require steel producers to introduce innovative measures to reduce costs, CO2 emissions and improve safety. The paper introduces the latest development of an automatic and continuous refractory maintenance system for the electric arc furnace (EAF), tailored of the requirements of modern steel production at an American steelplant. The automatic system has eliminated the disadvantages and inherent in intermittent refractory maintenance and follows the “No Person on the floor”- Safety-Philosophy. The functionality of the SCANTROL™ 4.0 system (laserscanner driven measurement of refractory thickness, visual representation of scanned results and intelligent material application) has significant enhanced productivity, working conditions and decision-making capabilities of steel operators. The 5th generation Laserscanner technology with more than 10 million measuring points per Scan in a furnace enables wear to be determined with a very high degree of accuracy and, thanks to the high measuring point density, joints and cracks can also be detected. With the help of the measurement data, an intelligent program calculates exactly the critical areas that need to be repaired. Furthermore, the quality and the required quantity of the repair gunning material is proposed. The information thus obtained is used to automatically control a gunning robot for repair of the refractory lining. This machine applies the repair compounds exactly where they are needed in the furnace. The overall effect at the steelplant has included: • Reduction in total refractory consumption • Increased furnace availability by reducing “Power Off” delays. • The ability to effectively maintain all areas of the furnace • Extending the available production period between brick relines • Improved operational safety • Integration of the determined data into an “Industry 4.0” environment

Lang, Oliver, Primetals Technologies Austria, Austria

Co-Author: Martin Schuster, Primetals Technologies Austria • Bernhard Winkler-Ebner, Primetals Technologies Austria • Alma Olivos, Tata Steel IJmuiden B.V. • Krister Fröjdh , Proximion AB

Abstract: "The installation of optical fibers with Fiber Bragg Grating sensors in the copper plates of a continuous casting mold, used for temperature sensing is getting more and more common. It has been proven to work in all types of casters like slab casters, casters with funnel molds for endless strip production and even in bloom casters. With several thousand of measurements points, optical fibers offer completely new insights into the casting process. With small distances between the Fiber Bragg Gratings and advanced evaluation algorithms, the mold level can be determined for the complete mold perimeter. The advantages of a temperature-based calculated mold level compared to electro-magnetic measured mold levels are shown. Electromagnetic mold brakes and stirrers are becoming state of the art to reduce inclusions and to achieve better surface quality results. Based on simulations, these electromagnetic devices are usually tuned to the desired operating conditions. However, in reality, there are many more influencing factors and disturbances such as clogging, so the actual steel flow is not known. With an indication of sub-meniscus speed and analysis of mold level and temperature distribution in the mold the Mold Expert fiber can help to characterize real steel flow and evaluate the influence of the electric field. Another area where this large number of measurement points can help is cast start. It will be presented how this critical event is monitored and how cast start breakouts can be prevented."

Latypova, Renata, University of Oulu, Finland

Co-Author: Jukka Komi, University of Oulu • Vahid Javaheri, University of Oulu

Abstract: Abstract: This study investigates the effect of rapid tempering and cementite morphology on hydrogen permeation and diffusion in a medium carbon steel. Three materials were tested: (1) direct-quenched, (2) direct-quenched and rapid tempered at 420°C, and (3) direct-quenched and rapid tempered at 720°C. The results showed that rapid tempering at 420°C and 720°C led to a significant decrease in the dislocation density of studied materials compared to the direct-quenched sample. In addition, higher tempering temperature resulted in a higher fraction of cementite precipitation as well as a change in the cementite morphology from the continuous stick-like structure to a more fragmented, discontinued, and globular type. Electrochemically hydrogen permeation tests revealed that direct-quenched samples could reach the saturation level much faster than the other two tempered samples and also had the lowest diffusion coefficient. It means less trapping site to be occupied but stronger to hinder the hydrogen mobility. Direct-quenched and rapid tempered at 720 °C needed a relatively longer time to reach the saturation level but on the other hand, it showed the highest diffusion rate among all samples. Overall, this research highlights the morphology of cementite and dislocation density of the studied samples in the hydrogen permeation and diffusion properties which is very important when developing of hydrogen-resistant steels.

Laubrock, Miriam , Fachhochschule Münster, Germany

Abstract: One essential criterion for the design of joints in many applications is the fatigue behaviour with a coincident focus on lightweight design. In this case an increase of load cycles by the use of high strength steels in combination with welding is limited. Experiences from sectors like automotive engineering show, that bonded joints exhibit excellent behaviour under cyclic loads. Nevertheless, there is only a low use of adhesive bonding in sectors like agricultural engineering, commercial vehicles or plant engineering. One important reason for that is mainly a lack of regulations and standards, as they already exist for the design of welded joints. Typical standards used are for example IIW-guidelines, the Eurocode or the FKM-guideline. They allow the determination of Woehler curves for welded joints, while a design method for adhesive joints is not included. In addition to that, the boundary conditions in these sectors are different to those seen in automotive engineering. They can be characterized by a lot of small and medium sized companies using a large proportion of manual manufacturing methods. Further differences arise from the wall thickness of the steel sheets used, tolerances and the corrosive conditions caused by the respective environment. In order to fill this gap, a design method for load-bearing adhesive joints in applications using thicker steel sheets was developed according to the FKM-guideline. The method is based on only few input variables to create a Woehler curve and to estimate the operational stability of an adhesive joint as it can be used in the sectors mentioned.

Lee, Jaemin, Hyundai Steel Co. , Korea, Republic of

Co-Author: Joohyun Park, Hanyang University • Jongoh Jo, Hyundai Steel Co. • Daehoon Shin, Hyundai Steel Co.

Abstract: In these day, Carbon Neutrality is important issue in the world. And iron&steelmaking industry is also undergoing process change to achieve carbon neutrality. The biggest change is process transitions from BF-BOF to DRI-EAF. In case of BF-BOF process, They can produce from normal grade of steel to AHSS grade steel. But this process need to generate a plenty of CO2 emission, 1.85tCO2/steel ton.[1,2]. On the other hands, DRI-EAF process is also possible to produce from normal to AHSS, But this process CO2 emission is just half of BF-BOF, 0.97tCO2/steel ton. In other words, producing steel using an EAF is more effective in terms of CO2 emission compared to BF-BOF process. And by using DRI in EAF, They are able to produce high grade steel. EAF technology is developing from 1968 to 2010 in the direction of saving EAF energy consumption. The use of industrial wastes in EAF technology is important part in terms of diversifying raw materials for EAF in the future, and this technology can meet another jump up in saving EAF energy consumption. And using industrial wastes also decrease CO2 emission. In this study, I share some case of using industrial wastes in EAF especially Al dross. In case of Al dross, we put the Al dross in EAF with Fe powder and Na2CO3. Fe powder aim to increase density of Al dross product and Na2CO3 is for stabilizing P2O5 activity coefficient in slag. In this paper, we share our experience of using industrial waste in EAF and we also share our future works related to use wastes.

Lee, Minjoo, Hanyang University, Korea, Republic of

Co-Author: Jongoh Jo, Hyundai Steel Co. • Joohyun Park, Hanyang University

Abstract: In order to reduce CO2 gas emission, steel companies are trying to develop the EAF steelmaking process instead of BF(–BOF) route by employing high amounts of DRI/HBI. DRI/HBI as a substitute for virgin scrap in EAF have been used because DRI/HBI does not have tramp elements. Unfortunately, however, commercially available DRI contains a relatively high level of phosphorus, which adversely affects the properties of steels. Although the previous studies on melting and phosphorus removal behavior in an EAF process involving partial use of DRI/HBI in conjunction with virgin scrap have been studied, the melting and dephosphorization behavior in EAF process conditions employing the 100% DRI/HBI have been less frequently investigated. Hence, we observed the morphology and distribution of elements with gangue oxides in HBI and investigated the phenomena occurred in EAF process using fully HBI as an alternative iron source using a high-frequency induction furnace at 1550oC. Main composition on gangue oxide in HBI was SiO2, Al2O3, and CaO in conjunction with unreduced iron oxide. Various size distribution of SiO2-(Al2O3-CaO) particles were entrapped in reduced iron matrix as well as in unreduced iron oxide phase. Small amount of siliceous slag was formed when HBI was melted, thus, phosphorus content in steel was not varied during the melting stage. This is possibly due to the formation of relatively acidic slag chemistry. To increase the dephosphorization efficiency, the distribution ratio of phosphorus between metal and slag was calculated using FactSage software by adding CaO in the furnace. The distribution ratio of phosphorus increases by adding CaO up to about 50% beyond which the melting point of slag is over 1500oC. So, the optimization of CaO content in the slag are required not only for maximum dephosphorization efficiency with good foamability but also for minimum slag volume with less refractory corrosion.

Leigh, David, Rio Tinto plc, Australia

Co-Author: Chris Dodds, Chemical and Environmental Engineering, The University of Nottingham • Michael Buckley, Rio Tinto

Abstract: Rio Tinto has been working on technology pathways which do not require the use of coal for processing Pilbara iron ores to iron and steel for well over a decade. Use of natural gas, hydrogen and biomass as reductants has been studied with a unique option combining microwave energy with raw sustainable biomass (rather than char) showing strong potential. Testwork with single “briquettes” made from a range of raw sustainable biomass including agricultural wastes, purpose grown energy crops, macro and micro algae with Pilbara iron ore fines indicated the potential of the process at laboratory scale. Initial scale up to 1000 briquette batches confirmed the early testwork and has positioned the technology for development of a 1 tonne per hour continuous pilot plant.

Leitner , Reinhold, Primetals Technologies Austria, Austria

Co-Author: Christoph Aigner, Primetals Technologies Austria • Thomas Zauner, Primetals Technologies Austria

Abstract: "The entire steel industry is going through the irreversible process of digital transformation and increasing plant automation to meet the requirements in terms of productivity, safety, quality as well as increased flexibility in production. A digital caster has many challenges and sub-tasks that must be achieved along the way to end up with a fully digitalized plant operation. The fully integrated casting platform with automatic controlled sequence operations starting from connecting the ladle on the turret to fully automatic tundish operation and start cast by means of robots and highly integrated automations systems limits the need of operator interventions to an absolute minimum. Thus, not only results in a reproduceable high quality caster operation but also increase operator and machine safety. One crucial aspect is controlling the casting speed of the plant by an advanced expert system right from start cast until the last slab has been cut. All influencing factors such as optimal soft reduction, the casting practice or machine restrictions are brought together to calculate an optimal casting speed throughout the entire casting process. The paper gives an overview about a digital caster and outlines the latest innovations in continuous casting automation on the way to a fully automated caster. "

Li, Dongsong, RWTH Aachen University, Germany

Abstract: Thickness requirements must be met when determining toughness properties in typical Charpy or fracture mechanics testing. As a result, the characterization of toughness qualities is a challenge in thin-walled constructions. This problem can be solved by replacing Charpy impact toughness testing with impact notch tensile testing. Toughness requirements, however, are still specified in terms of conventional test findings. As a result, a framework for translating these standard test criteria into impact-notch tensile test requirements is proposed here. The proposed framework is based on numerical simulations with a phenomenological damage mechanics model, which predicts local damage and global fracture using state-of-stress-dependent, strain-based criteria. This model considers the impacts of non-proportional strain routes and uses different cleavage and ductile fracture criteria to accurately anticipate the activation of cleavage and ductile fracture mechanisms in the associated numerical simulations.

Linden, Wolfgang, SMS group, Germany

Co-Author: Alexander Feldermann, SMS group • Volker Paersch, SMS group

Abstract: The metals industry is on its way to replace the high CO2 emissions generated by the use of fossil fuels with renewable energies in order to achieve climate-neutral steel production. Rising prices for fossil fuels and the increase in CO2 taxes are further incentives for switching to a climate-friendly energy supply. The time is now for SMS group to make the most of its unique core competencies, technologies, and partnerships to provide all climate-neutral processes from a single source. With its pooled expertise in process and energy management, SMS group is able to connect all plant areas to a cost-efficient power supply network. This is achieved through a central connection to the public AC grid and available renewable energy sources, for instance solar or wind energy, as well as to energy storage units that include battery storage systems. The paper explains, how DC ECO GRID from SMS group connects these to hybrid power networks (AC and DC), thus improving the plants' energy efficiency. Thereby a holistic solution from SMS group combines energy management consulting services, a defined business case, the development of concepts and solutions, and the integration of systems – all from a single source. The DC ECO GRID helps to provide a greener, more energy-efficient power supply for steel plants, both new and existing. In this way, it creates a link between a more environmentally friendly metals industry and new green energy supply systems.

Lis, Konrad, Lublin University of Technology, Poland

Co-Author: Grzegorz Winiarski, Lublin University of Technology • Tomasz Bulzak, Lublin University of Technology • Łukasz Wójcik, Lublin University of Technology

Abstract: The forming of railway axles is carried out using forming techniques. Rotary forging and open forging are used to produce railway axles. However, in order to increase the efficiency of the process by reducing the time needed to manufacture the product, as well as its energy intensity, it is necessary to propose an alternative forming method. To this end, research work is being carried out at the Lublin University of Technology, including the development of cross wedge rolling technology using flat tools, as well as skew rolling using three cone rollers. A test stand in the form of a numerically controlled inclined roller mill has been developed, enabling the forming of products whose final shape is obtained as a result of the sequential movement of three work tools. The machine developed is characterised by its high versatility of use due to the numerical control system used, which makes it possible to manufacture products on the basis of their envelope outline. The aim of the study was to analyse the geometric dimensions of the railway axle forgings obtained by the skew rolling method. Measurements were taken of the shape deviations, including the roundness of the individual steps, as well as the straightness of the axles. A non-contact measuring method using the GOM Scan 1 optical measuring system was used.

Liszio, Peter, thyssenkrupp Steel Europe AG, Germany

Abstract: Coking plant Schwelgern set the state of the art of cokemaking after commissioning in March 2003. This presentation is reflecting over the last 20 years and gives a resume about its pro and cons of design, production, environmental and management developments, raw material optimization and a future outlook.

Long, Christopher, Hatch Ltd., South Africa

Co-Author: Hamid Ghorbani, Hatch Ltd. • Robert A MacCrimmon, Hatch Ltd. • William Wang, Hatch Ltd. • Lori Hay, Hatch Ltd. • Kyle Chomyn, Hatch Ltd. • Samantha Jarrett, Hatch Ltd. • Luis Felipe Gomez, Hatch Ltd. • Jorge Luiz de Oliveira, Gerdau Acominas S.A. • Lucio Eustaquio dos Santos, Gerdau Acominas S.A.

Abstract: Gerdau’s integrated iron and steel plant at Ouro Branco, Minas Gerais State, includes a melt shop containing two basic oxygen furnaces (BOFs). The primary hot metal charging crane of 340t capacity has suffered structural damage including cracking and local deformations to girders and trolley structures after more than 30 years of operation. This damage presented a threat to the continued campaign life of the crane. Critical risks associated with this damage necessitated a thorough technical assessment to quantify the current structural condition, determine likely failure modes, and investigate possible options for continued safe operation. A campaign life assessment was performed, and life extension strategies were developed to minimize risk, maximize production, and improved reliability conditions. Root cause analysis and subsequent fitness-for-service assessment were carried out, including a strength and stability assessment, identification of cracking mechanisms. This led to the development of a range of options for mitigation and the associated constraints / monitoring requirements / etc. These strategies included short-term local repairs and monitoring strategies that could be completed without interruptions to overall production, as well as with long-term repairs, reinforcements, and local platework replacements to extend the campaign life until a replacement crane is procured and installed. These actions were successfully implemented, thus allowing for reliable continued operation of the crane, with major financial benefits to the melt shop facility. Keywords: Basic Oxygen Furnace; Melt Shop; Overhead Crane; Charging Crane; Fitness-for-Service; Campaign Life Extension.

Long, Edward, Primetals Technologies UK, United Kingdom

Co-Author: Richard Harvey, Primetals Technologies UK • David Osborne, Primetals Technologies UK

Abstract: "Blast furnace stave design robustness has significant impact on the longevity of secure, reliable blast furnace operations. Blast furnaces are forecast to be in operation for years to come, but ultimately will be replaced by alternative steelmaking routes. A likely impact for blast furnace operators is to extend campaigns. Short interim repairs will become the norm, with major rebuilds and relines (which can take many months) becoming less common. The purpose of the stave cooling system is to preserve blast furnace shell integrity making it suitable for many campaigns without change. Consequently, it is imperative to avoid premature failure. Copper and cast iron staves have been shown to bend, due to thermal effects of hot and cold sides, resulting in pipe connection failures and water leaks into the furnace. Additionally copper staves have experienced excessive wear as a result of cold abrasive materials being present at the furnace walls. These problems became well known in the early 2000’s. Primetals Technologies studied these phenomena and developed patented solutions to prevent bending in the critical area of the staves, as well as using abrasion resistant, hot face inserts. These retain burden material & whilst allowing freezing of soft, melting materials and create a wear barrier. Results from regular monitoring of current wear-resistant installations have validated the continued presence of the wear-resistant solutions and demonstrate the potential for many decades of copper cooling staves life. Additionally the data reveals that copper staves with wear-resistant solutions retain more stable and lower heat loads through the range of operating conditions. The conclusion from this is that an additional benefit of fuel saving can be realised. "

Lu, Yu-Chiao, KTH Royal Institute of Technology, Sweden

Co-Author: Chuan Wang, Swerim AB • Björn Glaser, KTH Royal Institute of Technology • Andrey Karasev, KTH Royal Institute of Technology

Abstract: Replacement of the blast furnace process with direct-reduction (DR) process coupled to an electric arc furnace is the key to realizing low-CO2 steelmaking and a climate neutral economy for Sweden. Direct-reduced iron (DRI) can be produced from reduction of iron ore pellets with H2 or CO gases in a shaft furnace, or from heating of carbon-containing pellets in a rotary hearth furnace. The addition of biomass to the pellets increases the porosities and thus the reducibility of pellets in both processes. The volatiles released from biomasses contain some amounts of reducing gases, such as H2, CO, and CH4, which can also contribute to the reduction degree and kinetics. By using biomass-containing pellets, a lower reduction temperature or a shorter reduction period could be obtained in both DR processes, which increases process efficiency and decreases energy consumption. Hydrochar is a bio-coal produced from hydrothermal carbonization treatment of organic wastes. Hydrochar has high volatile content and it may also act as an effective organic binder, which can be used for iron ore pellets making and carbothermic reduction. In this study, two carbon-containing materials: a Lemon Peel Hydrochar (LPH) and an Anthracite were separately mixed with an iron oxide-containing material (pellet fine, PF) at a Cfix/O ratio of 0.7 for reduction. The mixtures were pressed into briquettes (~30 g) and heated up in N2 atmosphere at a heating rate of 5 K/min up to two final temperatures. The reduction degree of PF by the volatiles released from the carbonaceous materials was determined by heating up to 750 °C, and that by combination of volatiles and residual carbon up to 1100 °C. The significance of the obtained results for the gas-based and coal-based DR processes were discussed, followed by some concluding remarks at the end.

Lu, Yu-Chiao, KTH Royal Institute of Technology, Sweden

Co-Author: Christopher Hulme, KTH Royal Institute of Technology • Leyla Koort, KTH Royal Institute of Technology • Viktoria Sutorius Trollbäck, KTH Royal Institute of Technology

Abstract: Evaluation of non-metallic inclusions in Inconel 718 produced by conventional production and by additive manufacturing A. Karasev, V. Trollbäck, L. Koort, Ch. Hulme It is well known that non-metallic inclusions (NMIs), which are formed during steelmaking processes, can significantly effect on the final properties of steels and alloys. Therefore, it is important to investigate the inclusion characteristics (such as composition, morphology, size and number) in steels and alloys for comparison and optimization of production processes and improvement of product quality. This study focused on evaluation and comparison of main characteristics of NMIs in nickel-based alloy Inconel 718 produced by a conventional production route and by additive manufacturing. Since the common two-dimensional investigations of NMIs on polished metal samples has a number of shortcomings, three-dimensional investigations of NMIs on a film filter and on the metal sample surface after a soft electrolytic extraction were carried out by using scanning electron microscopy equipped with energy-dispersive spectroscopy. It was found, that most inclusions have similar compositions in both samples, However, significant differences were detected in the morphology, size ranges and numbers of the observed inclusions. For instance, the sizes of Nb,Ti-C carbides and Ti,Nb-N nitrides in metal sample produced by additive manufacturing are about 6 and 3 times smaller compared to the conventionally produced sample, respectively. Moreover, the number of inclusions observed in the additive manufactured sample is drastically larger than that in the conventionally produced sample. This is explained by the much higher solidification rate of metal melt in the additive manufacturing process. It was concluded that the electrolytic extraction method with subsequent investigations in the scanning electron microscope can help to determine some significant quantitative differences of NMI characteristics in Inconel 718 samples produced by different production methods. Key words: steelmaking, additive manufacturing, Inconel 718, non-metallic inclusions, electrolytic extraction.

Lücking, Friedrich, SMS group, Germany

Co-Author: Helga Evers, SMS group / QuinLogic • Thorsten Claff, SMS group / QuinLogic • Michael Raus, SMS group / QuinLogic

Abstract: Despite high capacities, the industry is heavily investing in new equipment for reasons of better product quality, additional grades, reduced CO2 and energy footprints. Given the complexity of new lines, regardless if it’s about Caster Host Strip Mill, PLTCM or CGL ensembles, achieving optimal production settings with all required processing variants and the typically reduced lot sizes in the Industry 4.0 world requires huge efforts and often takes longer than before. Fortunately, with all the instrumentation, measurement, and data capture technologies, advanced software concepts can be used to significantly speed up the start-up time. These software methods involve big data type of IT infrastructure as well as some of the most advanced machine learning methods. A unique aspect in this paper is the fact, that these advanced methods are not applied by specialists but directly through the operating personal – to achieve the best output of the new processing line. This paper will also use aspects from a new CSP® Nexus caster as well as a new CGL line.

Lytvynyuk, Yuriy, Elkem ASA, Norway

Co-Author: Antonio De Pretto , Elkem • Bjørnar Larsen, Elkem

Abstract: A transition of the steelmaking industry towards the green steel making and the reduction of CO2 emissions includes the substitution of the blast furnace route of pig iron production by melting of the Direct Reduced Iron (DRI) in electric furnaces, typically employed in ferroalloy smelting. Two types of furnace designs are presently offered by engineering companies, which operate in either an immersed electrode or brush arc mode configuration, but all of them are based on the application of Søderberg electrodes. Elkem Carbon Solutions, as the inventor of the Søderberg electrode technology, has over a century of experience in the operation of Søderberg electrodes in various pyrometallurgical processes and diverse configurations of electric furnaces. This paper provides an overview of the current features and latest trends in Søderberg electrodes, and their application within ferroalloy smelting, with a focus on the electrode operation under similar conditions to those envisaged for DRI smelters.

Maia, Breno, Lumar Metals, Brazil

Co-Author: Lucas Duarte, Lumar Metals • Alenisio Nogueira, Lumar Metals • Thiago Wandekoken, Lumar Metals • Paulo Hopperdizel, Lumar Metals

Abstract: After years of announcements, environmental questions finally take destak place. Others side, more steel amounts are necessary to support human grow up population. EAF starts strong movements to reduce carbon emissions or find substitutes that promote carbon credits. This paper compare behaviors of carbon fines from main different sources: vegetal and mineral inject by Power Carbon technology from Lumar Metals. Results showed no difference in EAF process but huge difference of carbon impact over environmental questions.

Maia, Breno, Lumar Metals, Brazil

Abstract: The practice of Slagplashing is already consolidated industrially. However, there are still uncertainties about the relationship of the boom parameters and their effects on the slag. This article presents a comparison of the similarity of two 300t converters, one in Ukraine and the other in Brazil, with the 1/10 scale acrylic model of the LASIP located at the Federal University of Minas Gerais and their respective slagsplashing patterns. The results will be compared using an improved version of the equation of motion in determining the jet penetration over the slag layer and the ejection of material to cover the refractory walls.

Maia, Breno, Lumar Metals, Brazil

Co-Author: Marcelo Duarte, Lumar Metals • Willian Lima, Lumar Metals • Marcelo Guerra, Lumar Metals • Bernardo Braga, Lumar Metals

Abstract: The integrated plants suffer the need to adapt their processes to contribute to carbon reductions. One option of many BOF converters is the replacement of scrap with hot metal. Building on theories from the 80s and using modern computational mathematical simulation resources, Lumar developed an innovative lance tip with afterburner on the face. Patented product with the differential of being a lance with three tubes and supersonic post combustion nozzles. The results show an average increase in scrap percentage, shorter blowing time and integrity of the lance conditions.

Manocha, Sanjeev, LanzaTech, United States

Co-Author: Tobias Plattner, Primetals Technologies Austria • Alexander Fleischanderl, Primetals Technologies Austria • Wim Van Der Stricht, ArcelorMittal

Abstract: The Iron & Steel industry is in the decarbonisation era facing significant regulatory, political and technical challenges. Moreover, with aging Blast furnaces due for reline, steel mills are at critical decision-making moment to pick the most economic and sustainable solution. We believe that eliminating carbon emissions will be achieved through the integration of multiple technologies to deliver bespoke solutions suited to local conditions. Amongst the options is an innovative carbon capture and use technology developed by LanzaTech. LanzaTech converts carbon-rich gases into sustainable fuels and chemicals by a process of gas fermentation, with biocatalyst that feed on gases. LanzaTech’s naturally-occurring biocatalyst has been optimized to provide economic routes to ethanol and other chemicals from a variety of carbon-rich gas streams, including industrial off-gases from steel and ferroalloy mills, agricultural or MSW waste, and even CO2 from Direct Air Capture (DAC). By capturing the carbon contained in these gas streams, LanzaTech’s gas fermentation process reduces industry carbon emissions whilst producing chemical building blocks like ethanol that can be used directly for cleaning products or fragrances or converted to sustainable aviation fuels or the key ingredients needed for a broad range of consumer products including detergents, packaging and textile fibers. Products made with LanzaTech’s process offer an improved environmental profile and reduce greenhouse gas emissions by over 70% when compared to equivalent products derived from fossil fuels. This is the circular economy in action. LanzaTech technology has been successfully deployed in 3 commercial operating facilities at a steel and 2 ferro alloy mills, with 7 additional commercial plants in construction and several more in the engineering phase. The first European commercial scale plant, Steelanol, is soon due for commissioning at the ArcelorMittal Ghent combined with the Torero biomass project, with the objective of producing 80 million liters of bio-ethanol/year.

Marcukaitis, Boris, DANGO & DIENENTHAL, Germany

Abstract: Forging manipulators are large machines used in open and closed-die forging and ring rolling. They can easily weigh as much as 1,000 tons and are used to position workpieces of up to 350 tons, moving them safely in all six degrees of freedom. They can only fulfill their function if the axes are reliable and precise, and the hydraulic control system works perfectly. Such highly dynamic machines are typically the bottleneck in manufacturing. If the manipulator stops working, so do the press and furnaces. This usually also impacts downstream processes like heat treatment and machining. The growing need to save both on maintenance and spare parts calls for new methods to keep systems operational. To increase the availability of these machines, DANGO & DIENENTHAL is developing a system for the early detection of failures of individual machine components. The system involves the installation of additional measuring systems to the standard sensors already installed. Various test programs employ a predefined movement profile to check the individual functions of the machine and record the registered times, vibration spectra, and pressure curves. The measured values thereby obtained are stored and compared with the results of the machine in new condition. The results are evaluated and a new remaining service life is calculated for the individual components. DANGO & DIENENTHAL will be able to offer this optional new functionality in the near future. The option increases machine availability and prevents unplanned system failures. It alerts customers to an impending breakdown, allowing them to obtain spare parts in time. Once these parts are available, the faulty parts can be replaced during the next scheduled shutdown.

Mariani, Laura, Hatch Ltd. , Canada

Abstract: Electric arc furnace steelmaking now accounts for nearly a third of global steel production. As decarbonization of the industry is pursued through electrification and hydrogen-based direct reduction schemes, the volume of steel produced in EAFs will increase, as will the volume of slag generated as a by-product. Declining ore grades, limited scrap availability, and increased use of DRI will magnify this issue. Valorization of EAF slags has historically met with limited success and many operations simply stockpile or landfill the hundreds of thousands of tonnes of slag they generate each year. Continuation of these strategies is not sustainable and new waste management strategies must be widely adopted. This paper summarizes the factors that will influence future pathways to valorize EAF slags in the context of the development of a truly sustainable steel industry. An outlook for the future of sustainable EAF slag management is also provided.

Martinez, Jorge, Tenova HYL, Mexico

Co-Author: Jorge Martinez, Tenova HYL

Abstract: Among the various approaches for decarbonization of the steelmaking industry, Direct Reduction has proven to be the right solution, thanks to the readiness of the technology, effectiveness in abatement of the GHG emissions and cost effectiveness. When using DRI, two main routes should be considered, based on the intensive use of hydrogen (H2) (CDA) and capture and use of CO2 (CCU). One consists of the progressive conversion of the BF-BOF facilities to direct reduction-electric arc furnace (DRI-EAF). The second alternative is the production of hot metal (HM) by installing a gas-based direct reduction plant feeding DRI to an open slag bath furnace (DRI-OSBF). ENERGIRON®, the DRI technology by Tenova and Danieli, is the benchmark for sustainability and provides the needed flexibility during the current historic period of energy transition. Schemes for liquid steel production with reduced or practically nil carbon input by using H2, its equivalent cost for DRI production and the reduction of CO2 emissions are analyzed

Martinez Muniz, Sergio, Fives Stein, France

Abstract: Following the global trend towards higher environmental sustainability/green industry, steel processing plants continue to develop new technologies, with new slab reheating process technologies offering major opportunities to help reach green steel targets, not only to minimize the carbon footprint but also to reduce plant operational expenditure. This paper introduces new equipment and services for reheating furnaces to reduce energy consumption, scale production and emissions. Multi-fuel combustion (including hydrogen) and energy recovery systems are fundamental new technologies that will also be reviewed.

Martinez Rehlaender, Eloy, SvMet Engineering S.A., Mexico

Abstract: Casting operating temperatures for thin slab casting are key to achieve production levels that are comparable to conventional slab casting. Casting temperatures also determine key quality factors like internal segregation. Even more important is the effect of superheat on mold powder behavior during casting. It is well known that mold powders can have critical transformations in the mold which in turn change the heat transfer characteristics. In this paper it is shown that achieving superheat control for thin slab casters can be done with the use of hybrid models. Hybrid models results show clear advantages such as very narrow window of operation for any steel grade. {15~30 C and 20~30 C}. It is also shown that heat sequence transition is much faster with the use of hybrid models.

Martinsson, Johan, Swerim AB, Sweden

Co-Author: Niklas Kojola, Hybrit Development AB • Oscar Hessling, Swerim AB

Abstract: In view of transforming the heavily fossil-dependent iron and steel production into a fossil-free hydrogen-based production, the iron ore pellet could be modified to better suit the fossil-free iron and steel production, including the whole value chain. Considering the higher production cost associated with green hydrogen, the pellet could be optimized to save both material and energy costs during the melting and refining processes of the hydrogen direct reduced iron (H-DRI). At the same time, the modified pellet must keep sufficient mechanical properties as well as reduction properties. A preliminary study is therefore conducted, where the effect of varying CaO/SiO2-ratio was studied with regards to mechanical properties of the pellet, the reduction rate, as well as the dephosphorization ability (wt% P in iron) of the resulting autogenous slag. For this purpose, pellets with three different CaO/SiO2-ratios were studied, ranging from 0.8-1.4. In addition, two iron ore discs were made to broaden the CaO/SiO2-ratio range from 0.2 to 2.4 for the dephosphorization study. The three pellets were supplied by LKAB. Cold compression tests were made to determine the mechanical property. A high temperature resistance furnace was then employed to both follow the reduction of the iron ore using 100% hydrogen, and for melting the H-DRI to study the dephosphorization. While the reduction rate and mechanical properties did not vary significantly within the studied CaO/SiO2-ratio range, it was found that small differences in basicity in the autogenous slag could affect the dephosphorization significantly. The present work therefore finds it highly possible to optimize an iron ore pellet to save material and energy costs during the melting and phosphorus refining.

Masuyama, Asuto, NIPPON STEEL ENGINEERING CO., LTD., Japan

Abstract: As the environmental problems become more serious in recent years, Iron and Steel Industry has been making various efforts to save energy and reduce CO2 emissions, especially in order to achieve carbon neutrality. Under such circumstances, coke dry quenching (hereinafter referred to as the “CDQ”) are attracting attention due to the following advantages. ・Power generation utilizing sensible heat of hot coke ・Improvement of Blast Furnace productivity leading to lower CO2 emissions Recently, NIPPON STEEL ENGINEERING CO., LTD. improved power generation by approximately 7% compared to conventional CDQ. In addition, our CDQ automatic control system, integrated with coke oven operation, enhances CDQ benefits and reduces running cost. This paper describes our latest CDQ technologies, including new power generation cycle and automation technology.

Mathur, Tarun, ABB AB, India

Abstract: Artificial Intelligence (AI) is a key enabler for amplifying return on investment for digital technologies. There are many examples of big data, cloud platforms and data integration investments in the steel industry though much fewer for intelligent applications that convert this data into value. The complex nature of operations in a steel plant along with unavailability of large historical data pose a significant challenge to deploying artificial intelligence projects. This paper details several applications of AI in steel manufacturing for operational excellence, process performance and reliability improvement. The first application concerns improvement of manual and complex operation of the steelmaking shop using data from all meltshop processes, ladles, cranes etc. to build a machine learning model that predicts temperature losses for heats. It then prescribes the lifting temperature to the ladle furnace operator resulting in better superheat compliance, thus improving average caster speed and reducing energy input at ladle furnace. The second application uses data-based models to predict and control process performance by utilizing the well-known Model Predictive Control framework. This kind of application works in a closed loop with the automation system, correcting PID setpoints towards a more profitable operating range. These applications work well for slower and continuous processes such as those in pellet or sinter plant, grinding, reheat furnaces etc. The third application relates to how reliability can be improved by combining asset and process information. It’s applied in downstream rolling processes to analyze coil and process data in different phases, make correlations and label the operations data, and then use this labeled data to make predictive models. Some of these models are also prescriptive, providing the operator with exact action needed to avoid an anomalous situation.

Matskanis, Nikolaos, CETIC ASBL, Belgium

Co-Author: Guillaume Ginis, CETIC ASBL • Sebastien Dupont, CETIC ASBL • Rami Sellami, CETIC ASBL

Abstract: Steel production involves separate manufacturing sites for each production phase and various stakeholders in the supply chain. All these sites are consuming and producing heterogeneous data that is often not efficiently exploited (no data aggregation, coalition), which impede the added value of a global overview of processes, quality and security assessment. In addition the growing use of automation and interconnection of Cyber-Physical Systems causes an increase of the attack surface and new challenges and security risks for industrial control systems.A platform with global overview of production quality and security over multiple sites that is multi-tenant and multi-actor and supports the aggregation/integration of data, would facilitate the anomaly detection in all stages of production and plants involved. Additionally allow application of remediation strategies to all involved sites. We propose a solution based on the FADI framework for deploying and orchestrating a Big Data management and analysis platform for each plant in the production chain. Such platform instance is called a federated FADI instance. Then, a global, federal FADI instance will be configured in order to communicate with the federated instances and combine received data for ensuring an overall overview on the production chain and anomalies detection. By interconnecting these instances, we will obtain a FADI Federation. FADI leverages the Collaboration, Automation, Lean, Measurement and Sharing principles of the DevOps approach to ensure that software is produced with a high level of quality and speed by integrating development (Dev) and operations activities (Ops). In order to address the new security threats, the FADI framework will be augmented with security services to secure the software development life cycle, improving the immunity of the system. This DevSecOps approach automates security activities in the software continuous integration and deployment pipeline including security response processes for assisting operators and security remediation processes using the FADI Vacsine tool.

Matsuda, Kosho, Nippon Steel, Japan

Co-Author: Ryuta Ishino, Nippon Steel Corporation • Seiya Teruya, Nippon Steel Corporation • Kenichi Higuchi, Nippon Steel Corporation • Kaoru Nakano, Nippon Steel Corporation • Hiroshi Mio, Nippon Steel Corporation

Abstract: The reduction of carbon dioxide emission is one of the most important issues in the steel industry due to the large CO2 emitter. The steel is mainly produced by reducing iron ore using a blast furnace (BF), and its reducing agent is mostly carbon. Therefore, a low Reducing Agent Ratio (RAR) operation of the blast furnace is one of the solutions for reducing CO2 emissions. Kimitsu No.2 BF has been trying the low RAR operation by optimization of burden distribution, improvement of burden materials quality and so on. To further reduction of the RAR, the high-temperature blast operation is suggested to be an effective improvement. Because the high-temperature blast can raise an input amount of heat in the furnace, and it leads to the reduction of the RAR. Before operating under the high-temperature blast, there were two considerations; i.e. the one was the evaluation of the RAR reduction, and the other was the upgrading the hot blast stove. The reduction of RAR under the high-temperature blast operation was evaluated using a 2-dimensional mathematical model, and it was estimated that the RAR could be reduced below 490kg/t-p by 1300°C. The original hot blast stove had a limitation at 1200°C due to a heat resistance of the checker brick bracket. Thus, the material of the checker brick bracket was replaced with a high heat-resistant one. This new material made it possible to raise the blast temperature over 1300°C. The high-temperature operation was carried out in Kimitsu No.2 BF from 2019, and the RAR was able to be reduced to 492kg/t-p. This operating results were correlated well with the estimated value from the mathematical calculation.

Mattern, Tim-Oliver, Carl Bechem GmbH, Germany

Abstract: This paper evaluates modern grease technologies available for continuous casters and the impact to bearings and other aspects of maintenance. Grease performance for continuous casters can be largely impacted by the thickener technology, where resistance to water, steam, and high temperatures can degrade the grease. The mobility of the grease in centralized distribution systems can also be influenced by radiant heat before it is ever introduced to the bearing, adding another layer of complexity. Selecting the proper grease will impact the volume of grease consumed, how it behaves in the centralized distribution system, and how well it protects the bearings from this harsh environment.

Mattern, Tim-Oliver, Carl Bechem GmbH, Germany

Abstract: This paper covers the practical improvements that have been achieved in a tube mill just from changing from traditional grease to Polyurea technology. Tubes are either formed and welded or seamless rolled. Both processes require many steps and mill equipment that is exposed to load, heat and cooling fluids. In this harsh environment the equipment needs to work reliably without unexpected and expensive breakdowns. Most of the equipment is grease lubricated and while traditional greases have provided predictable performance in the past, their deficiencies often result in increased consumption to simply maintain basic reliability expectations.

Mayrhofer, Anna, Primetals Technologies Austria, Austria

Co-Author: Franz Hartl, Primetals Technologies Austria • Krzysztof Pastucha, Primetals Technologies Austria • Bernhard Voraberger, Primetals Technologies Austria • Helmut Kühböck, Primetals Technologies Austria

Abstract: "Steelmaking industry currently goes through the process of digital transformation heading to fully automated operations. The growing pressure from the global steel market for competitive steel making pushes towards increased plant automation. Highest productivity, flexibility, optimized product quality, precise and stable target achievement and at the same time lowest production costs are main demands for BOF and AOD operation. A continuous optimization and improvement of the converter process automation system is essential to reach the constantly increasing demands. In order to meet these challenges, we provide modular solutions for continuously closing the gap between the current situation of equipment as well as daily practice and the overall vision of an automated operation. We will illustrate how flexible cross process optimization leads to optimized steelmaking performance. Knowledge can be generated out of historical data and combined with digitalized know-how of experienced operators. This forms a digital knowledge base allowing assistance for maintenance and the handling of standard as well as exceptional operational situations. This paper drafts the journey to fully automtic converter steelmaking and possiblities to ensure state-of-the-art functionality, compatibility and cyber security throughout the life-time with subscription license models."

Mayrhofer, Anna, Primetals Technologies Austria, Austria

Co-Author: Xuedi Schmoelzer Deng, Primetals Technologies Austria • Thomas Reindl, Primetals Technologies Austria

Abstract: "In a ladle treatment station or ladle furnace station, calculation of desulfurization, aluminum fading and homogenization is a difficult task due to the dynamic nature of molten steel/slag movement controlled by bottom stirring. In traditional model, those parts are normally calculated separately with individual parameter setting. The traditional way needs a lot of parameter adjustment work for different project, due to different ladle size and plug conditions. In the recent developed level 2 model by Primetals Technologies, the reactions, which are led by kinetic movement of molten steel/slag, are considered as a whole part. The key to the new method is a kinetic model which predicts circulation movement of molten steel/slag with regard to ladle size, plug condition, bottom stirring flow rate and height of steel/slag. The result of the new kinetic model gives on average a more precise prediction of sulfur and aluminum value during treatment."

Mayrhofer, Anna, Primetals Technologies Austria, Austria

Co-Author: Helmuth Aflenzer, Primetals Technologies Austria • Thomas Reindl, Primetals Technologies Austria

Abstract: "The wide variation in the charged materials is the greatest unknown in the operation of electric arc furnaces. This circumstance makes the optimized operation of the furnace very difficult, especially when static profiles are used to control the process. The use of intelligent sensors and advanced process models enables a reaction to the actual situation in the furnace and thus advanced dynamic process operation. The paper shows the advantages of a dynamic process control for an electric arc furnace: An optimized operation can be reached regarding use of raw materials, electrical energy, process gases and the reduction of the CO2 footprint."

Mehrain, Stephane, Fives Group, France

Abstract: In current fast-evolving markets, Steelmakers are facing two types of simultaneous challenges. The first is related to new products and processes which require higher performance technologies and new digital solutions whereas a second challenge is overlapped with the need for green operations. Deep emission reductions are not achievable without innovation in technologies and materials. While innovative technologies are under development to use hydrogen, electrification and carbon capture, use and storage (CCUS), most of potential emission reductions are today coming from improvements in technology performances and in material efficiency. This paper presents the technology pathways to decarbonization and how innovations in technologies and materials contributes to both challenges through some examples in various fields of carbon steel and electrical steel processing. These advanced process technologies and digital solutions offer new avenues for steelmakers to expand their portfolio to higher-added value products, and to boost the productivity and environmental performance of their operations.

Meier, Fiona, RWTH Aachen University, Germany

Co-Author: Andreas Janz, Hüttenwerke Krupp Mannesmann GmbH • Alexander Babich, Independent Ironmaking Consultant • Dieter Senk, RWTH Aachen University • M. Efetürk, Hüttenwerke Krupp Mannesmann GmbH • R. Peter, Hüttenwerke Krupp Mannesmann GmbH

Abstract: Effect of the co-injection of PC and coke oven gas on the raceway and shaft phenomena in a blast furnace Injection of coke oven gas (COG) containing about 60% of pure hydrogen and nearly 25% hydrocarbons, has a potential for lowering the CO2 emissions from a blast furnace (BF). Hüttenwerke Krupp Mannesmann (HKM) in Duisburg has commissioned a COG injection system to operate blast furnaces with injection of PC and COG via two lances in the tuyere. In order to optimise this technology, a theoretical and experimental study on the raceway conditions, coal conversion, as well as pellets and sinter reduction behaviour while injecting COG has been conducted at RWTH Aachen University. In this contribution, first, the analysis of the COG influence on the BF process parameters and the effect of tuyere and lance design on PC conversion were undertaken. Then, injection trials using the MIRI plant were performed with varying PC and COG amounts while keeping constant blast temperature and oxygen enrichment. Furthermore, COG was replaced with natural gas. The conversion degree is determined based on the offgas analysis. Coal residues are undergoing microscopical investigations. Next, isothermal reduction test of pellets and sinter at three temperatures (850, 1000 and 1150°C) under two gas compositions with different contents of CO, CO2, H2, H2O and N2 were conducted using a 3-zone tube furnace. Mass losses were measured continuously during the test and the reduction degree was determined. In addition, changes in material microstructure and morphology were analysed using a scanning electronic microscope combined with EDX.

Mengel, Christian , SMS group, Germany

Co-Author: Sebastian Richard, SMS group • Ivars Valdmanis, SMS group • Lars Gillgren, SSAB AB

Abstract: Digitalization in metallurgical industry is a focus in current development enabling process engineers and maintenance staff to optimize their processes and help solving problems in their daily work. Condition monitoring systems collecting relevant data from the process is aiming at monitoring the health of the main components. SMS groups Genius CM program package is offering several monitoring functions in the field of vibration analysis and mechanical and hydraulic machine parts making use of field units for local data collection and analyzing process data to derive information on the condition of the equipment. Within the rolling equipment of hot strip mills the conditions of the mill stands is of major importance. Bad mechanical conditions can lead to rolling problems e.g. roll positioning issues, thickness errors, cambered strips, tailend cobbles, strip surface defects or unplanned roll changes. New monitoring functions have been developed and applied focusing on the integrity of the mill stand. These are analyzing - the parallelism of the rolls indicating unacceptable wear conditions in the stands - the hysteresis of the roll positioning equipment monitoring the conditions in the force transmission components - and the roll force measurement equipment. Model based calculations and helping functions are targeting at optimal user support to determine the most critical equipment conditions and focus on the relevant steps for maintenance and required service actions. The paper gives a short introduction on the modular Genius CM software package and describes the new developed monitoring functions. Application cases of different hot rolling mills will give an insight of the possibilities for trouble shooting and measures to detect and solve acute problems in daily mill operation.

Mertas, Bartosz, Institute of Energy and Fuels Processing Technology, Poland

Co-Author: Robert Baron, Koksownia Częstochowa Nowa Sp. z o.o • Sten Yngve Larsen, Eramet AS • Michał Książek, Sintef AS • Anna Rodź, Institute of Energy and Fuel Processing Technology • Grzegorz Gałko, Institute of Energy and Fuel Processing Technology • Małgorzata Wojtaszek-Kalaitzidi, Institute of Energy and Fuel Processing Technology • Michał Rejdak, Institute of Energy and Fuel Processing Technology • Bartosz Mertas, Institute of Energy and Fuel Processing Technology

Abstract: The carbothermal reduction process is used to produce manganese ferroalloys. One way to reduce CO2 emissions from the process in which coke is used would be to replace fossil carbon with renewable biomass carbon, which is considered to be carbon neutral. One of possibilities is to use bio-coke as a substitute for typical coke made of only fossil coking coal. Bio-coke can be manufactured on the basis of coking coal with the addition of materials of biomass origin. Blends for the production of bio-coke should have acceptable cokemaking properties to allow to produce bio-coke of appropriate quality. The paper presents the results of the on-going research project on the influence of the addition (up to 20%) of bio-materials of different origins to the coal blend on its cokemaking properties, i.e., Gieseler Fluidity, Arnu—Audibert dilatation and caking ability (Roga Index). The bio materials used in the research were raw and thermally processed waste biomass of different origins (forestry: beech and alder woodchips; sawmill: pine sawdust; and the food industry: hazelnut shells and olive kernels) and commercial charcoal. Presented results show that the amount of additive as well as the type of material affect the obtained coking properties. The presentation also contains the results of the quality parameters of bio-coke made on the basis of a coal blend with the addition of up to 20% of thermally processed biomass - charcoal. The evaluated parameters were: reactivity to CO2 (CRI), CSR post-reaction strength, structure and texture parameters. The presentation will also show the results of earlier research conducted at SINTEF: CO/CO2 reactivity, electrical resistivity and reactivity to MnO (slag-reactivity). Studies have shown that the quality parameters of the bio-coke produced on a large-laboratory scale meet the requirements for the reductant in the process of smelting manganese ferroalloys in submerged arc furnaces.

Millner, Gerfried, Materials Center Leoben Forschung GmbH, Austria

Co-Author: Lorenz Romaner, Montanuniversität Leoben • Daniel Scheiber, Materials Center Leoben Forschungs GmbH • Manfred Mücke, Materials Center Leoben Forschungs GmbH

Abstract: The production of steel coils with scrap material using an electric arc furnace (EAF) results in a very low CO2 emission compared to traditional production in blast furnace followed by basic oxygen steelmaking, but introduces many tramp elements by scrap. The impact of these foreign elements on the mechanical properties is in many cases not entirely understood and predicting the impurity effects on mechanical properties of steel from processing solely with physical models is not feasible. In this work we present a data-driven approach applying AI regression model techniques to predict r-value, tensile strength and other parameters of cold-rolled steel strip produced by voestalpine Stahl GmbH. The data includes a full chemical analysis, as well as many parameters measured during all working steps of the process and the resulting mechanical properties. As a prerequisite for training of AI models, the data needs to be understood, analyzed, checked, and unreasonable data be removed (data cleaning). The result is a machine-readable dataset fit for various modelling tasks. The used models include Random Forest Regression, Support Vector Regression, Artificial Neural Networks and Extreme Gradient Boost. Based on the insights gained, we present strength and limitations of different model types with the available data and number of features. In addition, we are presenting methods to calculate the feature importance and determine the impact of each feature in our models. Furthermore, we discuss possible improvements like introducing prior physical knowledge.

Minovsky , Johannes, Vesuvius Europe, Germany

Co-Author: Matthias Schmitz, Hüttenwerke Krupp Mannesmann GmbH • Thomas Heerink, Vesuvius • Thorsten Bolender, Hüttenwerke Krupp Mannesmann GmbH • Martin Kreierhoff, Vesuvius

Abstract: The achievement of a sufficiently homogeneous solidification structure in the as-cast state already represents a decisive qualitative aspect in the production of high-alloy steel grades that are used for applications such as roller bearings, crankshafts, or components for the engine. The production of these applications belongs to the engineering long segment. Specific standards for round, square, and rectangular formats have been developed by the end customers to achieve the requirements for internal quality and mechanical properties. Over the years, when casting high carbon & high alloy grades, the use of an EMS (Electromagnetic stirrer) has become a standard. The declared goals for the semi-finished product of high-carbon grades are to achieve a high proportion of equiaxed area, to reduce segregation, and to avoid cavities in the as-cast product. A new generation of swirl designs was tested on the HKM round-caster, and the optimization was underpinned using CFD. The casting texture evaluation was analysed with the help of an Ultrasonic-Device and amazing features - achieved with Super Swirl - could be proved. Keywords: Engineering Long, Round-Caster, EMS, Equiaxed area, High Carbon grades, Stirring Effect, Super-Swirl, HKM, Crankshaft

Mintus, Frank, VDEh-Betriebsforschungsinstitut GmbH, Germany

Co-Author: Susanna Bosi, ergolines lab s.r.l. • Loris Bianco, Feralpi Group • Matthew Phillips, Cardiff University • Min Gao, Cardiff University • Piero Frittella, ESF Elbe-Stahlwerke Feralpi GmbH • Tim Bause, ESF Elbe-Stahlwerke Feralpi GmbH • Nils Katenbrink, Quick-Ohm Küpper & Co. GmbH • Luca Petrucci, Centro Sviluppo Materiali SPA • Luca Innocenzi, Centro Sviluppo Materiali SPA • Ugo Chiarotti, Centro Sviluppo Materiali SPA • Matteo Chini, Feralpi Group • Daniele Gaspardo, Feralpi Group

Abstract: In the steel industry, large amounts of waste heat are generated in nearly all steps of the steelmaking process. The recovery of this waste heat could be a key technology on the way to net-zero steel production. Various technologies are available for this purpose, including the use of thermoelectric systems for power generation. The research project InTEGrated (Funded by EU-RFCS Programme, No. 899248) investigates the use of thermoelectric generators (TEGs) to recover thermal energy from two different waste heat sources: 1) EAF cooling water circuit and 2) radiation from steel products. Small prototypes were developed and initially tested in the laboratories. Based on the laboratory results and simulations, advanced prototypes were developed and installed for long-term tests at the EAF cooling water system at Ferriere Nord (Italy) and at the hot rolling mill of ESF Elbe-Stahlwerke Feralpi in Germany. Prototype design, results of prototype laboratory tests, simulation results and initial outcomes of the long-term tests are presented.

Mishra, Ritesh, Jindal Steel & Power Angul Odisha, India

Co-Author: Damodar Mittal, Jindal Steel & Power Angul Odisha India • Nadeem Khan, Jindal Steel & Power Angul Odisha India

Abstract: Jindal Steel and Power, Angul commissioned its first blast furnace of 4554 m3 in May 2017 at Odisha, India. This Blast Furnace has achieved productivity of 3.16 t/m3 of working volume/day by producing more than 12000 tons of hot metal in a day. Productivity improvement of large blast furnace is achieved by improving permeability inside the cylindrical structure of furnace by changing Sinter chemistry based on alumina percentage as higher alumina deteriorate the physical properties of Sinter, reducing fines and moisture input in terms of kg/thm, Modifying burden mix blending in main charging conveyor. This approach helped to increase oxygen enrichment with coal injection in the furnace to increase productivity.

Mitas, Bernhard, K1-MET GmbH , Austria

Co-Author: Ville Visuri, University of Oulu • Johannes Schenk, Montanuniversität Leoben

Abstract: The significance of iron droplets dispersed in BOF slag is researched regarding their contribution to overall refining kinetics. The droplet generation in the hot spot vicinity and their behaviour during their residence in the slag is modelled. Previously the consensus has been to focus on fine droplet dispersion when modelling BOF emulsion refining processes. This research indicates that the focus should be on mass transfer between the larger droplets and the slag when modelling emulsion refining.

Mittlboeck, Simon, Primetals Technologies Austria, Austria

Co-Author: Georg Keintzel, Primetals Technologies Austria • Konrad Krimpelstaetter, Primetals Technologies Austria

Abstract: "This paper deals with the development of a new technology for reducing and eliminating resonance vibrations in hot strip mills and thin-slab casting and rolling plants. The new system – called Vibration Dissipator - allows to stabilize and improve the overall process stability by reducing the vibration behavior of single finishing mill stands. The Vibration Dissipator is based on two combined physical effects. First effect represents the impact of a classical absorber, being an added vibratory element that is designed to “swallow” the resonance vibration. Second, an energy dissipating element which broadens the effective suppressing frequency range. The solution consists of special designed hydraulic elements, such as a combination of a capacity, a resistance and an inductance. This arrangement of design elements can be realized as a passive or semi-active energy dissipating hydraulic solution. A pure passive Vibration Dissipator was already successfully implemented on finishing stand 3 of an industrial hot rolling mill. The actual development targets focus on a semi-active concept with an adaptable hydraulic capacity. With this concept, it is possible to adjust the desired frequency of the Vibration Dissipator in a defined range. Since the frequency of these vibrations can change during the production, our concept allows a smooth adjustment to the actual frequency within seconds, in order to achieve an optimized damping effect. With our developed frequency identification system, it is possible to identify the actual frequency of the vibration which is currently appearing at the stand. Such a system consists of accelerometers and a sophisticated algorithm to evaluate the frequency. This frequency identification system is already implemented at another technological package from Primetals Technologies."

Mizuta, Keiji, Primetals Technologies Japan, Japan

Co-Author: Takanori Nagai, Primetals Technologies Japan • Hirokazu Kose, Primetals Technologies Japan

Abstract: The cooling speed over a certain level and the consistency of temperature profile are essential for the thermal cycle in the continuous annealing line (CAL) for an advanced high-strength steel strip (AHSS.) Because this particular cycle usually involves multiple water sprays, optimization of the spray pattern and nozzle arrangement, which affect the cooling speed and temperature, is expected to complete the requirements.The test to cool a rotating hot drum is conducted numerous times with various spray patterns and nozzle arrangements on the experimental equipment that replicates the process in the subject cycle as necessary and sufficient. A heated steel drum is rotated at the speed corresponding to the running speed of the strip. The water films formed on the inner surface and the intermittent cooling process are produced under the almost same conditions as in the actual cycle in the CAL. For the horizontal cooling pass, the drum is placed in an inverted position and given an appropriate taper angle so that the vertical distribution of the water film thickness formed by centrifugal force due to the rotation simulates the distribution of the water film across the width of the steel strip.Through those trials performed enough times, the ideal spray pattern and nozzle arrangement to cool an 800℃ strip of 1 mm in thickness to 100℃ at 1000K/sec or better and within ±10K of temperature consistency are identified.

Mochizuki, Chitoshi, Primetals Technologies Japan, Japan

Co-Author: Shinya Kanemori, Mitsubishi Heavy Industries, Ltd. • Gerard Goessens, Tata Steel IJmuiden, B.V.

Abstract: " Commonly in a commercial hot rolling mill the operator monitors the rolling situation at the mill pulpit. If the operator recognizes some abnormal rolling situation, he/she will intervene by adjusting the appropriate rolling mill actuator. Recognizing abnormal rolling situations and adjusting the actuators depends on the operator skill level. If instead a computer can detect the abnormal rolling situation and can automatically and appropriately correct the situation based on specific controlling logic, it is thought that the rolled strip quality could become better and more stable rolling could be achieved. For this purpose two kinds of rolling condition monitoring systems have been developed using image processing technology and those systems have been verified offline. Those systems are “strip shape trend monitoring system” and “strip pinching detection system”. The former has been achieved by utilizing the shape change of a reflecting light area on the strip, and the later has been achieved by utilizing the difference of the strip surface color between normal and abnormal rolling situation. The final target of this rolling condition monitoring system is to realize automatic intervention such as leveling or bending corrections by computer instead of manual intervention by operator. However, in the case of that the automatic intervention by computer is undesired, only manual intervention guidance indication for operators can be also selected. It enables detecting and notifying operators on critical conditions of rolling processes to increase quality and improve the productivity. With this paper we present an approach on how digital assistants can be deployed for industrial applications, especially hot rolling."

Modesto, Mariana, Vallourec, Brazil

Co-Author: Edney Arruda, Vallourec • Luis Germano, Vallourec • Stephane Houel, Vallourec • Leno Miranda, Vallourec • Alan Maia, Vallourec • Erica Bandeira, Vallourec • Klaus von Eynatten , EyCon - Steel Plant Technology Consulting

Abstract: Steel reoxidation during tundish filling represents a significative casting yield loss because the first casted billets are scraped in order to guarantee the product’s internal cleanliness. The present work shows the implementation of Tundish Inertization with argon during the start of casting of round billets in a seamless pipe producer. Several trials were conducted to define the optimal operational and process setups for a Delta-T shape 40ton tundish. The steel inertization capacity was validated through the evaluation of macro, meso and micro cleanliness in the final product. The avoided scrap signalizes expressive yield improvements and savings for the definitive installation, which is being industrialized.

Mohapatra, Sangram Keshari, Calderys France, France

Abstract: Direct reduction of iron technologies have proven to have lower CO2 footprint compared to the conventional blast furnace routes and are further moving towards higher hydrogen content in the reducing gas in order to minimize the direct CO2 emissions. High hydrogen concentration in the reducing gas may react with the refractory and change its texture, resulting in an alteration of chemical composition, thermal profile and affect the mechanical load bearing capacities of the refractory linings. This paper reviews the functional requirements of the refractory linings of a DRI reactor with higher percentage of H2 in the reducing gas and recommends optimum total solution, brick, monolithic and jointing products, based on the past experience and recent experimental studies.

Mohr, Andreas, Deutsche Edelstahlwerke Specialty Steel GmbH & Co. KG, Germany

Co-Author: Janosch Conrads, Deutsche Edelstahlwerke Specialty Steel GmbH & Co. KG • Karlheinz Hoeren, Deutsche Edelstahlwerke Specialty Steel GmbH & Co. KG • Horst Hill, Deutsche Edelstahlwerke Specialty Steel GmbH & Co. KG

Abstract: Additive manufacturing offers the possibility of producing geometrically complex components that cannot be manufactured by conventional machining routes. Due to this advantage, additive manufacturing is already being used in many fields of application such as medical technology or aviation. In general tooling for example, additive manufacturing can be used to realize optimized cooling channels, which can increase the production rate. However, there is currently a lack of tool steels that can be processed crack-free via additive manufacturing. As a result of their good processability, maraging steels such as 1.2709 have established as tool steels for additive manufacturing. These steels however are free from carbides, which results in lower wear properties than typical carbon tool steels. In the present work, it is shown how the tool steel 1.2083 can be optimized for use in additive manufacturing by an adapted chemical composition. The developed alloy can be easily processed in the Laser Powder Bed Fusion process and offers a hardness of 53 HRC already in the as-built condition. Furthermore, the tempering behavior is identical to that of 1.2083. Thus it is possible to produce additively manufactured components with properties comparable to a conventional carbon tool steel in mold making.

Monnoyer, Maxime, Fives Keods, France

Co-Author: Stéphane Mehrain, Fives Stein • David Barbier, Fives Keods

Abstract: UHSS and 3rd generation AHSS remain the best cost-effective solution for lightweighting of Automotive body in white applications, providing excellent combination of strength and formability. These steel grades are developed and processed in order to obtain multiphase microstructures with a substantial amount of retained austenite in order to achieve best possible ductility and in-use properties. Their processing imposes some constraints compared to conventional steels among which increased alloying contents, increased soaking temperatures, higher cooling rates, coatability and operational flexibility limitations. Such metallurgical and operational challenges can now be overcome thanks to key, newly developed, technologies whose advantages and features will be further presented. Induction technologies (Transverse and Longitudinal flux) allow rapid heating over a large temperature range as requested for the management of multiphase materials, thus avoiding the implementation and management of long conventional heating sections. Moreover, they allow efficient strip re-heating in the case of complex annealing cycles such as for example Q&P concepts. Application of wet cooling technologies achieve several objectives: first, high cooling rates enable managing all the product dimensional ranges without changing the metallurgical recipe whatever the strip thickness. Also, they allow fast and continuous cooling rate between high temperature soaking down to low quenching temperature as required by 3rd generation AHSS metallurgical concepts. Moreover, newly developed wet quenching technologies allow UHSS strip coatability even with high amount of Mn and Si. Overall, it can be demonstrated that new processing technologies dedicated to 3rd generation AHSS allow leaner metallurgical concepts and present high potential for cost and quality improvements.

Montazerozohour, Elmira, Primetals Technologies Austria, Austria

Co-Author: Bo Yang, Primetals Technologies Austria • Sergey Bragin, Primetals Technologies Austria • Carlo Piemonte, Primetals Technologies Austria • Andreas Jungbauer, Primetals Technologies Austria

Abstract: With the limitations of conventional technologies, the development of electrical steel grades is rather challenging and requires lot of experience, such as ensuring uniform thermomechanical conditions along the length and width of the strip. Contrary, the endless operation of Arvedi ESP (Endless Strip Production) delivers uniformity naturally by its process design. Moreover, this environmentally friendly technology leaves zero-carbon emission with minimum energy consumption which fulfils the global trend of green steel production. The hot strip produced on the ESP line shows high quality and the necessary properties, as well as energy and cost saving benefits, for a wide range of electrical steels. This paper presents an analysis of the ESP process characteristics with their influence on the final properties and quality of electrical steels.

Morice, Didier, AST Technology S.A.S. France, France

Co-Author: Fabrizio Masia, AST Technology • Said Alameddine, AST Technology • Geraldo Ferreira, AST Technology

Abstract: The quest for global optimization of Industrial processes to tackle environmental management recently took a new path thanks to the advent of big data analysis, IIoT, machine learning and artificial intelligence. During the last three decades, the industry in general has accumulated vast amounts of data but only a very small amount was generally explored and exploited. The new techniques mentioned, however, will enable the maximum benefit from all the accumulated data. The authors explain through tangible examples how supply chain and trade flows as well as available environment open-source databases can be pooled in the same data lake along with process data and explored with powerful analysis tools to twin not only the industrial process chain but also its footprint and impact on the environment. The authors conclude with a new emerging paradigm called “The Green AI”. This new paradigm will be used more and more extensively in the next decade to the benefit of Environmental Management. The obvious payback of this paradigm will be accompanied by major improvements of process and environmental factors.

Morishige, Seiji, KOBE STEEL, LTD. , Japan

Abstract: In the Advanced and Ultra High-Strength Steel (AHSS, UHSS) strip annealing line, press flaws, called “Pick-up”, generated on the strip surface are sometimes caused by hard deposits on the surface of the furnace roll. If “Pick-up” occurs, strip line operation is interrupted for maintenance and an exchange of rolls. The investigation of the “Pick-up” mechanism and its suppression have been invented by using an experimental method in which the reaction of the steel surface-layered powder and the thermal spray layer were considered. However, in this experimental method, the contact state between rolls and steel strip was not reproduced. In the actual conditions, we assume that sliding contact is an important factor in the initial adhesion of pickup. We developed a simulator in which the contact state in the annealing line could be reproduced. The simulator has a mechanism to rotate rolls, while pressing the roll against the steel, and slide horizontally at the same time. In this simulator, a new surface of the strip and rolls can be in contact continuously while reproducing the sliding contact. The atmosphere and temperature of the simulator can be reproduced under the conditions of the actual equipment. The contact pressure between the roll and the steel can be controlled based on the load cell measurement. The test results from the simulator, showed that it was possible to reproduce the same adhesion form as the furnace roll deposit. In addition, it was confirmed that the time to initial adhesion differs depending on the steel grade and the conditions under which the film is changed. By using this simulator, we were able to select the optimum thermal spray layer and introduce it into the actual equipment, achieving an extension of the roll life by avoiding “Pick-ups”.

Morrison, Colin, Primetals Technologies UK, United Kingdom

Co-Author: Rainer Klock, thyssenkrupp AT.PRO tec GmbH • Bartosz Smaha, thyssenkrupp Steel Europe AG • Hauke Bartusch, VDEh-Betriebsforschungsinstitut GmbH • William (Ross) Edmond, Primetals Technologies Ltd.

Abstract: "When operating a blast furnace, the ability to positively influence raceway characteristics and improve the permeability of the process, are key features that can enhance performance. The Sequence Impulse Process (SIP) is an oxygen pulsing technology credited with providing a way for blast furnaces to realise such benefits, at scale, today. This paper explains the technology and provides operational feedback from Schwelgern BF1, Germany operated by thyssenkrupp Steel AG. It discusses how regular injection of high energy SIP oxygen, has enabled a shift in operational outcomes. The total reducing agent rate and the carbon footprint have been lowered, as have heat loads to the tuyeres and shaft areas of the blast furnace. These compounded changes lead to significantly reduced OPEX and a rapid return on investment for the plant. Through the use of SIP, the performance improvements have been experienced even during periods of reduced burden material quality and have realised greatly enhanced stability characteristics in the blast furnace when compared to conventional operation. Raceway material analysis reveals improved conditions for metal/slag removal providing a mechanism for better drainage such that production level increases could also be considered. In utilising SIP, blast furnace operators now have a tool that provides flexibility to shift their operational drivers between gas utilisation, productivity and material use according to the requirements dictated by a multitude of influencing factors,"

Mosconi, Manuel, Tenaris S.A., Italy

Co-Author: Cesare Giavani, Tenova S.p.A. • Fabio Melloni, Tenova S.p.A. • Enrico Malfa, Tenova S.p.A. • Marta Guzzon, Tenova S.p.A. • Filippo Cirilli, Rina Consulting – Centro Sviluppo Materiali S.p.A • Loredana Di Sante, Rina Consulting – Centro Sviluppo Materiali S.p.A • Fabio Praolini, Tenaris S.A.

Abstract: Plasma Reactor to Recover Valuable Metal and Mineral Fraction from Steelmaking Residues Marta Guzzon, Enrico Malfa, Fabio Melloni, Cesare Giavani, Tenova S.p.A. Fabio Praolini, Manuel Mosconi, Tenaris Dalmine Loredana Di Sante, Filippo Cirilli, RINA CSM The EU production of steel in 2021 was more than 150 million tons: 56% from BF/BOF route and 44% from EAF route. This process produced several million tons of residues containing iron oxide, zinc oxide and other valuable metals. Tenova, according to the mission to develop sustainable solutions for the steelmaking, designed a stand-alone process, that can be operated in EU steel shop, to recover the valuable elements present in the steel making residues contributing to a reduced demand of primary resources in a circular economy approach. In the frame of Horizon EU – REMFRA project, Tenova together with Tenaris Dalmine and RINA- CSM will test at the industrial scale a Plasma Reactor for the recovery of iron oxides from different residues, implementing the use of secondary carbon carrier materials. The Tenova Plasma Reactor is based on plasma technology (electrical arc generated by graphite electrodes) working in reducing atmosphere. This pyrometallurgical process has been selected since it can: • treat a large variety of waste streams: by-products coming from the steel industry (slag, scale, dust, sludge), incinerator ashes, catalyst for vanadium (V, Ni, Mo, Co), Mn-sludge, Ni-dust, Al dross and red mud. • use as reducing agent residuals containing C (i.e. biomass, waste polymers, petro-chemical residues) • accept residual containing Si (ceramic, refractory and glass). In the paper, the status of activities and development of Plasma reactor in the frame of the REMFRA project will be presented.

Mousa, Elsayed , Swerim AB, Sweden

Abstract: Agglomeration is an essential part in the metallurgical industries, and it comes in the core of circular economy. The agglomeration can play a substantial role not only in enhancing the residue recirculation in the steel plant, but also in introducing the neutral biocarbon for replacing the fossil fuels and consequently mitigate the fossil CO2 emission. The agglomeration can be performed through different techniques such as sintering, pelletising, and briquetting. This study demonstrates the recent trends in pelletising and briquetting as potential pathways for sustainability transitions from the traditional iron and steel making route to the next generation H2-based steel route. Developing biocarbon briquette and/or biocarbon containing agglomerates with the quality fulfil the shaft furnace and/or electric arc furnace will be discussed. In addition, developing and optimizing pellets/briquettes using innovative binders are key approaches to improve the process efficiency, reduce the slag generation, and decrease the energy consumption. In this context, the developed agglomerates will be evaluated in terms of cold mechanical strength, hot mechanical strength, reduction behaviour, softening and melting which are essential parameters to judge the quality of the agglomerates. Keywords: Pelletising, Briquetting, Organic binders, Biocarbon, Recycling, Ironmaking, CO2 emission, Circular economy

Moustapha Houssein, Abdoulfatah, Calderys Deutschland GmbH, Germany

Co-Author: Pascal Hubert, Imerys Villach GmbH • Steffen Moehmel, Imerys Villach GmbH

Abstract: The new climate and environmental challenges have made the iron making industry move towards a cleaner production and therefore to a greener refractories consumption. The blast furnace being the main vessel in the iron making process, its tapping mainly relies on the quality of the Taphole Clay (THC). For a long time, coal tar bonded Taphole Clays were used for their easy injection and good adhesion to taphole walls but their high toxicity led to the use of phenolic resins. Despite their lower toxicity level, these resins are recently presenting some health issues for the plant workers especially with their free-phenol content which sometimes may be present up to nearly 10% in the resins. In this study, two different resin binding systems: a conventional phenolic resin and a low free-phenol resin were examined and compared. On a first hand, the effects of these binding systems on general plastic behavior of the products were analyzed and also correlated to their physical and mechanical properties. A comprehensive understanding of the Taphole’s severe operating conditions such as high temperature, high pressure, corrosion by slag and molten pig iron is required. Therefore, the injectability of the studied samples was investigated at high temperature in order to characterize the setting of the material, the cracks formation and the outlet of volatiles during the plugging mechanism of the Taphole Clay in the blast furnace. A chemical analysis of the Polycyclic Aromatic Hydrocarbon (PAH) present in the samples was also performed.

Muller, Clément, Fives Group, France

Abstract: Steel manufacturers are continuously developing higher performance steel grades by optimizing the chemistry at the steelwork and by changing the process parameters, in particular the heat cycles to be applied in the annealing furnaces. In hot dip galvanizing lines, the production of the latest Gen3 AHSS require higher annealing temperatures which are difficult to be achieved by using gas fired radiant tubes. The Galvannealing induction heating of the AHSS grades is also becoming an issue, due to the retained high fraction of austenite which results in poor magnetic properties for a heating by a conventional inductor. To fulfil the requirements of these new steel metallurgies, the transverse flux induction is the unique industrial solution. Fives has been developing the EcoTransFlux™ technology since more than 20 years, first for rapid heating of stainless steel in strip processing lines. Today, this advanced technology is becoming a key equipment for processing the latest Gen3 AHSS and also for developing high-grade electrical steel products for EV market. This paper presents the main features and performances of Celes transverse flux induction technology as well as different industrial applications and references.

Dr. Myungkyun, Shin, Senior Vice President, POSCO, Korea, Republic of

Abstract: In line with the global steel industry’s common goal to meet the Paris Agreement, POSCO has declared in December 2020 the achievement of ‘Net-Zero Carbon’ by 2050. The first objective is 10% reduction in CO2 emission until 2030 improving the efficiency of blast furnace operation by using high grade ores, hydrogen-rich gas, and AI-based operation. The second objective is 50% reduction until 2040 incorporating electric arc furnaces and HyREX process. The latter is a new hydrogen ironmaking process under development by POSCO which will gradually replace the current blast furnaces. The third objective is to reach net zero by 2050. Carbon-based ironmaking process will be completely replaced with hydrogen- and electricity-based process.. The HyREX process consists of multi-staged fluidized bed reactors (FBR) and electric smelting furnaces (ESF). Sinter feed is charged as the major iron source and hydrogen is the main reducing gas. The advantage of the direct use of sinter feed is in the availability and cost relative to high quality DR-grade pellets, whereas the larger amount of impurities in the form of gangue mineral need to be removed by slag-making in an electric smelting furnace. This route has the potential to resolve the restriction in the raw material shortages of H2-based DRI-EAF route. HyREX demo plant engineering is under progress on a fast track based on more than 20 year of in-house commercial plant construction and operational experience of FINEX FBR and ferro-alloy ESF. In this talk, the updated roadmap towards carbon neutrality of POSCO as well as the demo- and commercial-scale plant construction and process evaluation plan will be addressed. Additionally, the discussion on the R&D and pre-engineering results of hydrogen-based ironmaking process development will follow.

Nadur Motta, Ricardo Sebastião, Ternium, Brazil

Co-Author: Deilton de Oliveira Sousa , Ternium • Beatriz Lopes, Ternium • Deyvid Martins de Souza, Ternium

Abstract: This work aims to show the industrial development carried out to expand the PCI plant capacity of Ternium’s blast furnaces in Rio de Janeiro-Brazil. Ternium has got two blast furnaces with a daily production of 7500 thm each. The PCI plant's original design features have got two 60 t/h pulverized coal mills with two injection stations with dual vessels allowing average PCRs of up to a maximum of 180 kg/thm for each blast furnace. Over the years, the PCI plant has presented capacity and availability problems regarding the coal injection and grinding stations, affecting the plant's hot metal production and leading to losses due to the lack of coal and consequent instability in the operation of the blast furnaces. The PCI expansion improved the injection stations with the addition of a third injection vessel, a new coal silo of 800 tons and a third coal grinding mill and drying plant with the same type and grinding capacity and with alternative pneumatic transport increasing the versatility of the plant in general. In addition, dual coal lances were implemented with dynamic distributor and closed loops control allowing uniform distribution of coal between lances and higher PCR up to 220 kg/thm.

Nagel, Maximilian, thyssenkrupp Hohenlimburg GmbH, Germany

Co-Author: André Matusczyk, thyssenkrupp Hohenlimburg GmbH • Henrike Bröker, thyssenkrupp Hohenlimburg GmbH • Andreas Tomitz, thyssenkrupp Hohenlimburg GmbH • Max Müntefering, thyssenkrupp Hohenlimburg GmbH • Gerhard Gevelmann, thyssenkrupp Hohenlimburg GmbH • Marisa Taube-Levermann, thyssenkrupp Hohenlimburg GmbH • Stephan Kovacs, thyssenkrupp Hohenlimburg GmbH

Abstract: Modern applications demand high formability due to increased complexity in part designs. Conventional microalloyed steels are often limited in this respect. The new High Ductility (HD) grades solve that issue. In yield strength ranges from 315 up to 700 MPa, their outstanding local forming reserves enable a reliable production process even for components that require complex forming operations. Especially in the automotive industry easy to weld materials for lightweight applications – with higher strength levels and lower sheet thicknesses – have become more and more important in the recent years. The HD grades fulfill all normative requirements of the EN 10149 and VDA 239-100 respectively and can be used to easily replace conventional HSLA steels. Beneficial for the medium strength grades is also their higher value in scrap commercialization due to specifically designed chemical compositions. All available hot-strip HD grades are fully characterized regarding their local formability, hole expansion ratio, bending radii and welding behavior. Narrow scatter bands in material properties allow a smooth production. With their quasi-single-phase ferritic matrix, they are already applied in automotive safety components and modern axle designs within electric vehicles.

Najafian Ashrafi, Bahareh, K1-MET GmbH, Austria

Co-Author: Alija Vila, Primetals Technologies Austria • Felix Lindbauer, Primetals Technologies Austria • Martin Barna, Johannes Kepler University

Abstract: Continuous casting is the main method of steel production, with over 96 percent worldwide. Thus, optimizing this process can heavily impact the steel manufacturing costs. The application of electromagnetic fields in the continuous casting of slabs is a well-known method to control the flow field inside the cast strand. If applied properly, electromagnetic fields can result in an improved flow behaviour, consequently, minimizing the product defects. Electromagnetic fields are divided into two major categories: static and traveling magnetic fields. Electromagnetic Braking (EMBr) systems use static magnetic fields to stabilize the flow, especially in high casting speed situations. To control the molten steel flow more actively, travelling magnetic field systems with their greater capability to impact the steel flow were developed. Three different moving fields can be generated: Electromagnetic Level Stabilizer (EMLS), Electromagnetic Level Accelerator (EMLA), and Electromagnetic Rotating Stirrer (EMRS). Depending on the flow situation in the mould region, and the need for acceleration, deceleration, or stirring, each of these modes can be activated. Any combination of these traveling magnetic fields with static magnetic field is also possible. Although this combination makes the flow field much more complex, it provides the simultaneous flow control in the whole mould region (both above and below the submerged jets). The impact of EMRS without and with EMBR (combined mode) on the mould flow pattern were investigated in the current work. The results show that the surface velocities can be homogenized and increased due to EMRS. The combination with EMBr can cause homogenized surface velocities and reduced jet penetration length.

Nardini, Alberto, POMINI Long Rolling Mills Srl, Italy

Co-Author: Daniele Biagini, POMINI Long Rolling Mills S.r.l.

Abstract: The uses of long quality products (SBQ) increasingly require high metallurgical properties and excellent tolerances. Rolling these products therefore entails a fast process that requires high speed control and communication capabilities, with fast response electromechanical-hydraulic control systems. To offer high process stability, POMINI Long Rolling Mills has developed a finishing-sizing unit equipped with an AGC (Automatic Gap Control) system for the automatic control of the gap between the rolls, able to dynamically maintain the required dimensional tolerances. The finishing-sizing unit is placed at the end of the continuous train and consists of two vertical and horizontal two-roll stands. To control the size of the bar, the AGC system manages the dynamic positioning of the rolls, whose light variation is applied by means of synchronous screws operated by a hydraulic servomotor with proportional valve. With the finishing-sizing unit enslaved to the AGC system, a minimum tolerance of 1/5 DIN for round bars can be obtained. The same system is applicable, with the applicable changes in the product characterization, even with flat bars, for which a minimum tolerance of 1/4 DIN can be obtained. This paper describes the main process and features of the system. KEYWORDS: HYDRAULIC POSITION CONTROL, AUTOMATIC GAP CONTROL, FINISHING SIZING STAND GROUP, AGC CONTROL

Natsui, Shungo, Tohoku University, Japan

Co-Author: Mizuki Tanaka, Tohoku University • Ryusho Honda, Tohoku University • Andrey Stephan Siahaan, Tohoku University • Hiroshi Nogami, Tohoku University

Abstract: A numerical model of sintered iron ore deformation during ironmaking blast furnace processes helps to achieve superior process operations, particularly with the current goal of decarbonization. In this study, the high-temperature softening behavior of sintered iron ore characterized by a low-melting-point molten slag core and solid iron-rich phase shell structure was modeled using the Bingham plastic fluid model with an additional structural force that expresses the stiffness. The shape matching (SM) method was incorporated into the framework of the smoothed particle hydrodynamics (SPH) method, the stiffness parameter in the SM scheme was varied, and consistency with experimentally observed results was confirmed. The model was verified by comparing the simulated and experimentally determined 3D shape of sintered ore particles with different reduction rates after heating to various temperatures from 1473 to 1673 K. Furthermore, case studies simulating the softening and melting of the sintered ore particle bed in the cohesive zone were performed. We can expand this model's applicable range by experimental investigation of the effect of the composition of various types of ores on deformation behavior, and the mixing effect of various ores on bed deformation behavior could be clarified in detail.

Negri, Alessandra, Tenova S.p.A., Italy

Abstract: A. Negri1 1 Tenova S.p.A., Italy Key Words: emission, pollutant, steelmaking, fumes treatment plant, FTP, EAF, electric arc furnace, metallic charge, performance improvement, revamping. Abstract The main goal of fume treatment plants installed after electric arc furnaces have been, till today, to control temperatures, quenching and diluting the primary with the secondary fumes, and to remove dust with electrostatic precipitators or bag filters. Injection of activated carbon in the dust removal equipment often is present as a safety measure for the control of the micro-organics pollutants. Possible future scenarios can require different treatments, to comply on one side with presence of pollutants in the furnace off gas coming with low quality scrap, and on the other side with more stringent environmental requirement referring also to other source of pollution. It is therefore fundamental to identify first which of the above pollutants can be present in the fumes. This depends on the metallic charge melted in the furnace, and on the charging and melting method. Each component may be controlled in different ways: the reactions of oxidation, reduction, absorption and adsorption occur at different conditions, mainly related to a determined temperature window, turbulence and presence of reagents. This underlines the importance of designing a fume treatment plant locating each treatment in the position where it can be performed in the most economical way, e.g. promoting the reactions occurring at correct conditions of temperature and turbulence, avoiding the use of expensive catalyst and reagents as much as possible. In this paper considerations of basic engineering and cost estimation of the implementation of air pollution control known technologies to the electric arc furnace application are carried out.

Neri, Luca , SMS group, Italy

Co-Author: Luca Neri, SMS group Spa • Andrea Lanari, SMS group Spa

Abstract: Reduction of CO2 emission in steel production and transformation to green energy sources demand a highly efficient and flexible power supply for electric arc furnaces (EAF). Integrated BOF routes usually provide very weak grids, which do not allow the connection of demanding EAFs without major changes in the power network topology. The new family of IGBT based electrical modules is capable of feeding EAFs from 5 MVA up to 350 MVA. A fully modular technology concept provides the demanded efficiency and power density in order to serve the needs of the green steel transformation. Using this innovative modulation, technologies and proprietary control algorithms, which take full advantage of the power electronic capabilities, ensure highest power transfer and lowest impact on the grid’s power quality. A real project case is showing the challenges and needs of the implementation of EAFs for green steel production, and how the fully modular technology allows our journey into a CO2 reduced and green energy powered steel production.

Neuer, Marcus, VDEh-Betriebsforschungsinstitut GmbH, Germany

Co-Author: Andreas Wolff, VDEh-Betriebsforschungsinstitut GmbH

Abstract: Modern process industries is driven by decision making, decisions which need solid factual understanding of a situation. Through the recent successes of artificial intelligence, mainly due to its subfield of machine learning, prediction and knowledge models are available to support those decisions. Explainable AI (XAI) developed techniques for fusing expert knowledge, existing physical equations and easily to interpret relations to provide more insight into the result generation of machine learning models. Counterfactual AI provides a way to work with the available data and to introduce straightforward means of mathematical logic and conditional probability into real. Such systems can answer hypothetical question like „if the tension at the rolling would not have been too high, would the strip would still have been damaged“. This requires the AI system to first adopt a perspective that is not present in the current data set evaluated, second, to utilise all previously learned information and third to combine it in form of Bayesian conditional probabilities to actually predict the scenario in which the questioned parameters would have occurred. Counterfactual AI is therefore able to scan its own machine learning input variables for „what-if“ scenarios, which can be straightforwardly applied to selected use cases in steel processing and process industry in general. In more global context, Counterfactual thinking in autonomous systems is one step towards Causal AI. The latter combines common machine learning approach on data, causal inferences on the found relationships including counterfactual questions and lastly physics-informed approaches with analytical process models. The talk will give details on the described techniques and presents real world applications of the discussed methods. It will cover different processes of the steel production route like continuous casting and rolling, to display the advantages brought by Causal and Counterfactual AI.

Ney, Gerhard, Saarstahl AG, Germany

Co-Author: Dirk Deckers, Saarstahl AG • Steven Fries, Saarstahl AG • Marco Abram, SMS Concast AG • Andre Wildhaber, SMS Concast AG • Luigi Alessio, SMS Concast AG • Steve Münch, SMS Concast AG • Anke Britz, Saarstahl AG • Matheos Czarnynoga, Saarstahl AG • Ralf Thome, Saarstahl AG

Abstract: The new billet caster S1 at Saarstahl AG Saarstahl is one of the world leading suppliers of long products for demanding steel grades of special bar quality. The product portfolio includes a wide range of unalloyed and high-alloyed steel grades with a carbon content from 0.01 up to 1.0 wt.-%C, which are mainly utilized in the automotive sector. To underline its forefront technology position and to achieve further quality improvements, as well as production flexibility and capacity, Saarstahl ordered a new 5-strand billet caster named “S1” in 2017. Designed by SMS Concast AG, the caster produces 180x180mm2 billets. After the successful commissioning of caster “S0” and revamping of caster “S3”, this is already the third cooperation between both parties on a major caster project since 2005. The caster is equipped with Convex Mould Technology, consecutive stirring in mould (MEMS) and strand (SEMS) position, AirMist soft secondary cooling, Dynamic Mechanical Soft Reduction (D-MSR), automatic deburring, marking and sampling machines, speed and temperature measurements as well as an extended discharge concept including 4 silent turn over cooling beds. Among the technological equipment, the installation of the 12 MSR units, which are comprised by six double modules, must be highlighted. Each reduction roll is capable to apply up to 1000kN of force to ensure intense soft and hard reduction. The optimum steel grade specific reduction pattern are adjusted online automatically based on the process conditions and casting parameter to ensure lowest segregation and porosity levels and therefore highest internal quality. 24 months after awarding the contract to build the new “S1”, the caster had its first cast in November 2019. This paper shall outline the main technological features in detail and reflect the quality results that could already be achieved in standard production after an intensive hot commissioning and testing period.

Nölle, Christoph, VDEh-Betriebsforschungsinstitut GmbH, Germany

Co-Author: Asier Arteaga Ayarza, Sidenor Investigación y Desarrollo • Monika Feldges, VDEh-Betriebsforschungsinstitut GmbH • Martin Schlautmann, VDEh-Betriebsforschungsinstitut GmbH • Norbert Holzknecht, VDEh-Betriebsforschungsinstitut GmbH

Abstract: A concept for estimating the risk of steel long products to develop surface defects during the production is presented, based on an advanced product tracking system and machine learning algorithms. The aim of the risk estimators is to identify products with a high risk for defects as early as possible in the production chain and to support operator decisions on corrective actions or the immediate recycling of a product in order to save resources for the further processing. In our use case, the secondary metallurgy, continuous casting and hot rolling processes are considered of relevance for the surface quality, and besides the raw process data also the results of a set of soft sensors are evaluated, which integrate physical process knowledge into the otherwise data-driven risk estimators to increase the reliability. Some challenges of the approach are discussed, such as difficult product tracking conditions, the need to retrieve aligned data from different sources and the availability of sufficiently broad datasets for training. A digital twin-based software platform for the integration of different data sources, soft sensors and risk sensors is presented, along with a data model based on international standards but adapted to our use case.

Ohno, Ko-ichiro, Kyushu University, Japan

Co-Author: Tatsuya Kon, Kyushu University • Taro Handa, Kyushu University • Yuki Kawashiri, JFE Steel Corporation

Abstract: In an oxygen blast furnace trial using an experimental blast furnace, it was confirmed that the oxygen blast furnace could operate at a high pig iron ratio of approximately twice that of a normal blast furnace. Owing to the higher productivity of the oxygen blast furnace compared to the standard blast furnace process, the internal volume can be reduced while maintaining the same productivity. This trend can help utilization of lump iron ore, which is generally not used in current blast furnace operation due to the low strength and poor reducibility of lump ore compared to sintered iron ore. To evaluate the possibility of utilizing lump ore in an oxygen blast furnace, slag formation behavior at the lump ore and limestone interface was investigated in this study. In order to evaluate the slag formation behavior in the cohesive zone, the softening behavior between pre-reduced lump ore and a CaO substrate in an inert atmosphere was measured under loading conditions using a softening simulator. From the results, the following results were obtained. When the lump ore melt intrudes to the CaO substrate, the solid part of lump ore penetrates into the CaO substrate with deformation of the CaO substrate, and the greater the degree of melt intrusion, the more lump ore penetrates. The melt intrusion behavior into the CaO substrate is strongly related to the presence or absence of Ca2SiO4 phase at the initial melt formation temperature. At 1300°C or lower, the gangue composition at the outer part of the lump ore decides intrusion behavior. At 1300°C or higher, the average gangue component of the entire lump ore is the main factor to make intrusion behavior.

Olivos, Alma, Tata Steel IJmuiden B.V., Netherlands

Co-Author: Sonja Strasser, Primetals Technologies Austria • Oliver Lang, Primetals Technologies Austria • Martin Schuster, Primetals Technologies Austria • Dirk van der Plas, Tata Steel IJmuiden B.V. • Stephen Carless, Tata Steel IJmuiden B.V.

Abstract: Mold thermal monitoring in continuous casting is essential for breakout prevention and to monitor process stability. Whilst useful, the number of thermocouples and coverage has been limited. Owing to these limitations, a mold containing Fiber Bragg Gratings (FBG) was developed to increase measurement resolution. This high-resolution grid provides the basis for various data analytics approaches to get a clear heat transfer picture and to characterize casting mold phenomena that until now have remained only accessible through modelling. We will present 3 main focus areas to gain better insights into the heat transfer picture. Firstly, an accurate temperature-based mold level measurement along the entire mold width has allowed to link mold flow with meniscus shape. Describing the meniscus shape has proven central to relate process parameters such as argon, throughput, and electromagnetic flow control to surface quality. Secondly, the information on heat transfer along the slag pool and meniscus area has allowed to observe localized performance of the melting powder behavior. This has served as accelerator to evaluate mold powder performance. Third, having the full heat transfer picture has allowed to observe in a very early-stage other process problems such as uneven mold powder infiltration and possible rim formation. Among the advantages of using FBGs as thermal monitoring tool is the ability to collect the process status in real-time. This enables the analysis of the process with statistical and other data analytics methods in a shorter amount of time. For this we have developed an interactive app where the results of the analysis are summarized and visualized. This allows faster and better-informed decision making for process optimization and incident prevention. The information, knowledge and algorithm development coming from FBG mold monitoring has allowed to capitalize the use of FBG as thermal probes in form of process reliability and product quality improvement.

Omelchneko, Volodymyr, thyssenkrupp Steel Europe AG, Germany

Co-Author: Sven Karrasch, thyssenkrupp Steel Europe AG • Christoph Toulouse, thyssenkrupp Steel Europe AG • Sascha Lang, thyssenkrupp Steel Europe AG

Abstract: The Continuous Casting Machine (CCM) Bruckhausen is part of an integrated steel plant of thyssenkrupp Steel Europe in Duisburg. The main customers are the market leaders in the packaging, automotive and electrical industries, who set high standards regarding the surface quality of their products. Due to the closeness of CCM and hot-rolling mill in Bruckhausen, the transition time of the slabs from CCM to the hot-rolling mill is quite short. This shortness has two main advantages. Firstly, it allows to save energy which is needed for reheating of slabs. Secondly, slabs with short transition time have fewer micro cracks on the slab surface. The short transition time, however, brings a big challenge for the production process, since it limits the time available for the quality control of the slab surface and exclusion, if defects are detected. The most frequent defects on slabs are longitudinal and transversal flame-cutting burrs/beads and different types of cracks. In the past, the slab surface was controlled by means of thermal camera to detect those surface defects. This technique has reached its limits regarding the present challenges for the quality of the slab surface. To fulfill continuously increasing customers surface quality requirements, in March 2022 we implemented the first slab surface inspection system of thyssenkrupp Steel. It is a 3D Surface Inspection System (SIS) supplied by IMS Messsysteme. Within six months after the installation of the 3D SIS the internal quality costs as well as quality KPIs of our customers had been improved. After giving a brief introduction in the principals of 3D SIS technique we will present the main advantages of the 3D SIS in comparison to a basic thermal camera detection system, the recent impacts on quality results and next planned development steps.

Ordieres Meré, Joaquín B., Universidad Politécnica de Madrid, Spain

Co-Author: Andreas Wolff, VDEh-Betriebsforschungsinstitut GmbH • Antonio Bello-García, Universidad de Oviedo • Stefano Dettori, Scuola superiore di studi universitari e di perfezionamento Sant'Anna

Abstract: Productivity in modern metals plants and processes depends on sophisticated computer-controlled automation systems that have become powerful, and ubiquitous. It is part of the Internet of Things (IoT). In the case of automation, the computers that make production smarter also make it more vulnerable to external interference. Manufacturers have become more vulnerable to cyber-attacks after shifting to Cloud infrastructure and services, since from 2017, there have been approximately 382 new vulnerabilities, and additionally, the crackers have had the tendency of exploring targeting vulnerabilities before the security research team and responsible software vendors realize their presence. After reviewing several RFCS research projects in the context of the RFCS EU funded dissemination project named ControlInSteel, it becomes clear that many of the created models for forecasting can be useful for estimating bias between expectations and measured values. Unlike earlier analytical attempts to find more effective model representations, the cloud oriented Operational Technologies provide scalable solutions enabling different applications. Such applications not only are useful for low level monitoring activities, but also to create higher level of representation of data, mainly product oriented with high traceability on the low-level data. This paper wants to present the different capabilities that cloud OT solutions enable, both in process monitoring, OT oriented cybersecurity, and high-level data representation. All the analysis will be carried out by using a case study from the hot strip mill for long products in the context of the EU funded Autosurveillance project.

Orsal, Bertrand, Dassault Systèmes, France

Abstract: The Steel industry is at a tipping point where sustainability and greenhouse gas emissions are top items on CEOs’ agendas. The old philosophy of engineering and production for profit is giving way to engineering and production for sustainability. Steel producers are adapting their business models, changing their priorities, and shifting their strategies as a response to the shifting market conditions. We know that this involves a transformation towards new ways of production limiting emissions like the direct reduction, but also capturing the CO2 emissions and optimizing the whole production chain. Dassault Systèmes provides a collaborative work environment (3DExperience) and comprehensive set of solutions that focus on green steel to enable and help accelerate this transformation. Solutions range from design, engineering and industrial process simulation capabilities to environmental assessment tools to calculate the impact of a plant over the course of its lifecycle. It includes a set of solutions to operate facilities such as integrating planning & scheduling. It provides capabilities for certification of green steel production through tracking of all plant data in a single source of truth platform. Find out how Dassault Systèmes and the 3DExperience platform make it possible to manage all industrial projects for green steel in the same collaborative space, for all roles involved, from design to production.

Oswald, Jonas, Dürr Systems AG, Germany

Abstract: In a world of limited resources, the reuse of materials plays an important role for building a circular economy. An established process in the recycling industry for removal of impurities from steel and metal pieces is the pyrolysis process. Hydrocarbons are removed at elevated temperatures. The process generates excess heat if the syngas produced is being utilized as input fuel. The usage of this excess heat for electricity production and, if required, for providing useful heat is a significant step to lower the Carbon footprint in these processes and additionally to reduce the operating costs. Dürr Cyplan has executed a best practice example which can be the blueprint regarding energy efficiency for the above-described processes in the steel industry. In this project shredded Aluminum waste is being processed in a rotary kiln (pyrolysis reactor) and purified to high grade Aluminum granulate. The rotary kiln is fired with the flue gases of the burned syngas that was generated in the pyrolysis process. The remaining excess heat from the flue gases is utilized in a high temperature ORC process at a temperature level of ~500°C. The Dürr Cyplan high temperature ORC-module can cover the own consumption of electricity for the whole purification process line and can additionally cover partially the demand of electricity of the whole factory. This brings a saving of ~140tons of CO2 annually* and lowers the electricity bill significantly. The described operating principle can be applied for the upgrading of metal and steel waste. Dürr Cyplan ORC modules can utilize heat with different interfaces to convert high temperature heat into electricity and additionally useful heat for follow up processes. This operating principle can be described as an electricity producing heat exchanger and can be applied in various process steps within the variety of metal and steel processing.

Overbeck, Theresa, VDEh-Betriebsforschungsinstitut GmbH, Germany

Co-Author: Gregor D. Wehinger, Clausthal University of Technology • Martin Kutscherauer, Clausthal University of Technology • Michael Hensmann, VDEh-Betriebsforschungsinstitut GmbH

Abstract: Increasing the use of hydrogen as reducing gas in direct reduction changes the reaction and operating conditions of the plant. Particle resolved computational fluid dynamics (PRCFD) offer insights into the surrounding gas flow and the reaction-diffusion mechanisms inside each pellet. As a first step, in this work a three-dimensional model of a single porous iron ore pellet is developed. The model represents the pore diffusion and internal stepwise reduction reactions from iron(III)-oxide to iron with hydrogen and carbon monoxide. The reactions are implemented in the gas and solid species and energy conservation equations. The model is flexible regarding the operating conditions (e.g. temperature), the initial pellet morphology, the initial gas and pellet composition and the gas composition at the pellet surface. The model allows the locally resolved investigation of the reduction progress inside a single porous iron oxide pellet. Radial differences in solid mass fractions go along with a varying porosity of the pellet. The influences of diffusion and reaction kinetics are investigated depending on temperature and gas and pellet composition. Especially, the diffusion of the produced water to the pellet surface can be a limiting factor and is further investigated. We will discuss these results with literature data and own analyzations of direct reduction pellets. In perspective, the model will be used for a PRCFD simulation of different reactor sections.

Overhagen, Christian, University of Duisburg-Essen, Germany

Co-Author: Linfeng Zhu, University of Duisburg-Essen • Wanyun Mao, University of Duisburg-Essen • Maolin Liu, University of Duisburg-Essen • Sichen Zhou, University of Duisburg-Essen • Kaiqi Fu, University of Duisburg-Essen

Abstract: Classical approaches of roll pass design (RPD) for finished full sections require a two-step method. First, main grooves are designed according to a predefined elongation distribution to meet the requirements of the intended process in terms of temperature evolution, power demand and section tolerances. In the second step, the intermediate grooves are designed in order to fulfill prescribed filling ratios, taking into account the specific spread behaviour of the rolling process. This process is a trial-and-error method and often requires a high number of iterations to yield a satisfying solution for all passes. Extra complexity exists for diamond-diamond pass sequences in which a final square section is produced in few passes without predefined main grooves with similarities to the three-roll process, suffering from the same restrictions. To speed up the design process and to initiate a framework for a fully-automated solution, the RPD problem is solved by a machine-learning method in the present study. Using the industrially approved RPD software MPC developed at our research group, we generated training data for the pass sequences round-oval-round, square-diamond-square and diamond-diamond-square in the two-roll process, as well as round-round and round-hexagon in the three-roll process, each for a range of roll diameters and total reductions. The fully-connected neural network trained with these data is able to predict pass designs within the trained data ranges. Verification data was generated which does not coincide with the training data to test the network against overfitting. Model results are presented and cross-validated against the analytical RPD model. The resulting ML pass design model is implemented in Python using the PyTorch library. Source code for including the parameters of the neural network will be published for third-party evaluation.

Padur, Frank, GMT mbH, Germany

Co-Author: Kristin Helas, GMT mbH

Abstract: Realistic material simulation is becoming increasingly worthwhile as part of simulation projects. If tolerances are to be calculated within a few hundredths or temperature variations within a few kelvins, the associated material data and models must also have a high degree of accuracy and match the conditions in the production process. The paper illustrates the influence of experimentally determined data, such as flow curves, temperature-dependent properties and CCT diagrams, and realistic material models, such as the microstructure and transformation model. Possibilities are shown to the user to apply the material knowledge for individual simulation projects, too. Various application examples illustrate the influence of accurate and validated material data sets on the simulation results of forming processes and heat treatments.

Panda, Sourav Kumar, Tata Steel IJmuiden B.V., Netherlands

Co-Author: Aart Overbosch, Tata Steel Nederland Technology B.V

Abstract: Lime is added during the converter process to remove phosphorus from steel. At the end of the converter process, some heats were found to contain undissolved lime, especially, the low phosphorous aim grades. The undissolved lime issue can be due to insufficient time after flux additions before the slag is tapped, formation of C3S/C2S layer on top of CaO flux which prevents further dissolution, and flux reach saturation limit which prevents further dissolution. One way to increase the lime dissolution is to increase the FeO content locally during the converter process. Dolomite is also added to the converter slag to control the MgO-C refractory dissolution by aiming right MgO-saturation level. Thermodynamic studies were performed using FactSage to determine “minimum FeO” content required within the converter slag which dissolves all lime that is added during the process. And, to determine the “minimum MgO” content required during converter slag to reach the MgO saturation level. The assumption in the current work is the fast kinetics of transfer of solid lime and dolomite to liquid slag when fluxes are added. FactSage-Macro function was used for determining the lime and MgO saturation limit for ~15,000 synthetic slag compositions within a specific range of composition and temperature. Regression formulas was then developed using the FactSage calculations which can calculate the “minimum FeO” and “minimum MgO” content for any given slag composition and temperature within that range. The formula will help design the local slag composition to avoid the undissolved lime issue and MgO-saturation level of the converter process.

Park, Tae Jun, Hyundai Steel Co., Korea, Republic of

Co-Author: Gang Won Lee, Hyundai Steel Co. • Hyeon Woo Park, Hyundai Steel Co. • Myoung Hwan Choi, Hyundai Steel Co. • Yun Kyum Kim, Hyundai Steel Co.

Abstract: So far, many researchers have made various efforts to improve the surface quality for automotive exterior sheet steel. Dross and Ash defects, which are major defects, must be effectively controlled to ensure the surface quality of automotive exterior sheet steel. In order to control these defects, various factors such as chemical composition, thermal equilibrium, and level management of galvanizing bath must be considered. This research relates to a process performed within a dam type snorkel included in the lower part of the snout facility, and this research improved an area where it was difficult for workers to monitor and control in real time and made the process smart. For this purpose, we’ll use camera and computing vision technology to analyze floating matter and flow rate of molten zinc on snorkel with optical technology to develop alarm system for operational risk, develop automatic control system linked to other facilities, and use it for process analysis. We’ll introduce the current status of technology development and additional process digitization plans using optical analysis technology of computing vision for the production of high-quality automotive exterior materials.

Park, Taechang, Hyundai Steel R&D Center, Korea, Republic of

Abstract: The construction of a smart factory platform for digital manufacturing is being promoted by international steel corporations. In this environment, we are implementing AI technologies to replace existing analysis methods and reduce human error. This is referred to as a "smart analysis system" by Hyundai Steel and focuses on the analysis of the raw materials used in ironmaking process as well as the evaluation of the quality of the final product. In this conference, I'd like to share two novel analysis methods for iron ore sinter with deep learning and chemometrics. In the agglomeration process, iron ore sinter is produced for use in blast furnace. Sinter quality and strength are related with the iron ore sinter's mineralogy and microstructure. By using an optical microscope, it is possible to identify the main mineral phases in iron ore sinter, which include hematite, magnetite, calcium-ferrite, and slag. To evaluate quality and operate the ironmaking process in relation to fuel cost optimally, it’s essential to evaluate the fraction for each phase. The phase classification and quantification in the field is currently carried out manually by an analyzer using the naked eye. In this study, a new automated analysis method using deep learning is proposed to replace human inspection for mineral phase fraction. It is notable that the automatic labeling method utilizing clustering analysis has significantly reduced the time required for deep learning-based semantic image segmentation. One of the parameters for the reduction index and reduction degradation index of iron ore sinter is the magnetite ratio. Every four hours in the field, the magnetite content has been measured using the titration method. The existing method, which requires a lot of time, is proposed to be replaced by a new analysis approach that employs Raman spectroscopy and chemometrics.

Park, Jiook, POSCO, Korea, Republic of

Co-Author: Dong-jo Lee, POSCO

Abstract: To meet the unprecedented demand of environmental issues and tightened production cost, fuel consumption to produce iron and steel must be minimized to the limit. In blast furnace, maintaining circumferentially balanced state is critical for stable operation and minimizing fuel rate. Circumferentially unbalanced state of furnace will result irregular burden decent, thermal level instability and poor gas utilization and so on. Hence, furnace operators carefully monitor circumferential information of furnace and take several actions to keep furnace stable. Among several actions, burden profile control is one of the most effective actions to change inner state of furnace and achieve minimized fuel rate. Generally, optimum burden profile can be attained by rotating chute control (speed, angle, etc.) in bell-less type blast furnace. Unfortunately, in conventional control concept, only radial directional burden control is possible while there is barely no tool to control circumferential burden profile. In this study, circumferential burden stock level balancing system was developed for circumferential burden profile controlling and balancing. To decide when/where to control, furnace circumferential information such as top gas temperature, sounding level and tuyere combustion status were continuously monitored and key control parameters were derived from DEM burden decent simulation of bell-less top charging system. Once burden stock level of specific direction is too low or too high, top charging system was controlled to attain flattened stock level. Developed system was installed and tested at Pohang No.3 Blast furnace and it was found that standard deviation of 4 direction’s stock level can be effectively reduced by the system.

Park, Joohyun, Hanyang University, Korea, Republic of

Abstract: It has been known that approx. 7% emission of CO2 arises from the steel industry sector. Hence, many steel companies are trying to develop the electric arc furnace (EAF) steelmaking process instead of blast furnace (BF) and basic oxygen furnace (BOF) integrated routes by employing high amounts of direct-reduced iron (DRI) and/or hot briquetted iron (HBI) to reduce CO2 emission. The DRI/HBI as a substitute for virgin scrap in EAF has been used because DRI/HBI does not have tramp elements. Unfortunately, however, commercially available DRI contains the relatively high levels of phosphorus and gangue oxides, which adversely affects not only the steel properties but also the operation efficiency. There have been many reports of several metallurgical factors affecting the EAF operations with the use of high amounts of DRI/HBI. In the present paper, the challenging points should be carefully considered to achieve the improved EAF technology on the way to green steel will be reviewed, and the recent experimental and modeling research will be discussed. For example, we observed the morphology and distribution of elements with gangue oxides in HBI and investigated the phenomena occurred in EAF process using fully HBI as an alternative iron source using a high-frequency induction furnace. Main component of gangue oxides in HBI was SiO2, Al2O3, and CaO in conjunction with unreduced iron oxide. To increase the dephosphorization efficiency, the distribution ratio of phosphorus between metal and slag was calculated using FactSage thermochemical computing software and was compared to the measured results. The optimization of slag chemistry is required not only for maximum dephosphorization efficiency with good slag foamability but also for minimum slag volume with less refractory corrosion.

Pauna, Henri, University of Oulu, Finland

Co-Author: Daniel Ernst, K1-MET GmbH • Michael Zarl, K1-MET GmbH • Isnaldi R. Souza Filho, Max-Planck-Institute for Iron Research • Hauke Springer, RWTH Aachen University • Marko Huttula, University of Oulu • Johannes Schenk, Montanuniversität Leoben • Timo Fabritius, University of Oulu • Dierk Raabe, Max-Planck-Institute for Iron Research

Abstract: Hydrogen plasma smelting reduction (HPSR) has the potential to be a viable solution for both reducing metal-bearing oxides and treatment of metallurgical sidestreams for metal recovery. However, thermal plasmas are known for their erratic and sometimes unpredictable behavior where the plasma may e.g. jump from place to place or have circular movement from side to side around the furnace. Furthermore, plasmas are highly dynamic entities, as their properties change rapidly depending on, to name a few, the plasma composition, electron density, and length. Since the composition of the ore will change in the reduction process, the plasma’s properties will also change during the smelting reduction. The need for online in situ process control is evident to keep the metallurgical process and the application of plasma aligned with the desired end-product reduction degree, composition, and quality. To address the demand for process control, the reduction of iron ore was studied at two lab-scale HPSR set-ups at the Montanuniversität Leoben and Max Planck Institute for Iron Research together with a demonstration-scale facility at K1-MET GmbH. Optical emission spectroscopy (OES) was used to provide a qualitative outlook on the HPSR process from an OES point of view by looking at the radiating species within the plasma and linking them to what is happening inside the furnace. As a measurement method, OES offers a way to monitor the plasma's composition, temperature, electron density, and other characteristics from a distance so that the plasma is not affected by the measurement itself. Since the focus is on process control, the aspects of OES as a process control tool to monitor the plasma are discussed.

Pawelski, Hartmut , SMS group, Germany

Co-Author: Alexander Ring, Thyssenkrupp Rasselstein GmbH • Martin Höß, Thyssenkrupp Rasselstein GmbH • Holger Pulst, SMS group • Christian Wietzig, SMS group

Abstract: In the cold rolling business, the trend towards thinner and/or materials with higher strength or generally improved mechanical properties is unbroken. For the DCR process (double cold reduction) in tin plate industry, this means production of grades DR9.5 (AISI/ASTM 623) or beyond, final thickness towards 0.1mm, and reduction up to 50% in a single pass. When roll gap lubrication conditions and strip tensions already are at an adequate level, reduction of work roll diameter remains the most efficient way to achieve these goals. For an existing mill, normally this affords an extensive revamp. To overcome this situation, a cassette with two smaller rolls was developed, which exactly substitutes one of the large work rolls in the first stand of a DCR mill, so that in fact a 5-hi configuration is created. The change between 4-hi and 5-hi mode and back is as simple as a normal work roll change. In the presentation, the theoretical aspects of combination of small and large work roll diameter and the influence of these asymmetric conditions on process parameters, material flow and properties are discussed. A prototype system was designed by SMS group. It was built in cooperation with thyssenkrupp Steel - Packaging Steel (Rasselstein) in Andernach and successfully tested in the first stand of Rasselstein‘s DCR mill NWW4. Technological features regarding drive situation, horizontal forces and flatness control are described. Measured process data is presented, which illustrates the potential, regarding roll force decrease in combination with high strip thickness reductions.

Pereira, Marcia, Vesuvius Ghlin, Belgium

Co-Author: Laura Grana Suarez, Vesuvius • Waldemir Moura de Carvalho, Vesuvius • Hervé Tavernier, Vesuvius • Marcia Maria da Silva Monteiro Pereira, Vesuvius

Abstract: In today’s competitive market, the demand for high-quality, defect-free steel is unprecedented in industry history. Quality standards have been raised worldwide along with increasing market pressure to reduce and control pricing. Perhaps, the most challenging period is associated with the start-up of the continuous casting sequence. Unstable mould conditions will adversely affect the steelmaker’s ability to control this critical stage of casting. This can lead to conditions resulting in poor cast quality, defects, and even breakouts. In order to get a faster and good and stable lubrication state in the mould, and so decrease risks of sticking or cracks formation, a simple solution consists of adding an exothermic powder on top of the steel in the mould, prior to the continuous casting powder. Through the use of computational thermochemistry (Software FactSage) we can explore and study the influence of the different raw materials on the energetic behavior of multicomponent and multiphasic systems, such as the in-mould behavior of the Flux powder. The thermodynamic calculations can be used to identify the reaction products inside a primary metal smelter, to establish overall heat and mass balances of a process, and to generate phase mappings (such as phase diagrams and predominance diagrams). The method is based on identifying the equilibrium state of a system constrained by different conditions of temperature, pressure, volume, chemical potentials, chemical compositions, and more with a short computational time. Consequently, the method allows us to predict the system behavior and quickly adapt the composition of our exothermic powders to the different local working conditions, steel grades, or standard casting flux while keeping the right exothermic behavior.

Perret, Fabian, Hüttenwerke Krupp Mannesmann GmbH, Germany

Co-Author: Alexander Babich, Independent Ironmaking Consultant • Dieter Senk , RWTH Aachen University

Abstract: It is almost impossible for the injected pulverised coal (PC) to be completely converted in the raceway at very high PC injection rates (≥ 200 kg/tHM). Therefore, it is crucial to understand whether the unburnt coal particles (Char) can be converted outside the raceway and, if so, to what extent. The incomplete coal combustion in the raceway leads to a decrease in the blast furnace (BF) productivity and operation efficiency and increases the specific coke rate. RWTH Aachen University intensively studies the properties, the behaviour, and the interaction of char with coke, iron burden, liquids, and gases outside the raceway. This contribution focuses on the fluid dynamics of gas-liquid flow in the dripping zone as well as the char effect on liquid products (hot metal and slag). To investigate these effects, an experimental BF dripping zone setup with ignited coke was developed. Several experiments including a reference test without injection were conducted with variable parameters such as the injected material (char, PC, coke fines), the injection rate, the hot metal temperature, the coke size, and the coke bed height. Thus, it was possible to evaluate the effect of these parameters on char behaviour as well as on static and dynamic holdups. In addition, the char effect of slag properties such as viscosity, basicity and melting range was examined using the simulation software FactSage™ and was afterwards compared with experimental measurements. These experiments and simulations are helpful for BF process monitoring and control as well as further prediction of char behaviour in the BF.

Philipp, Angela, Alleima GmbH, Germany

Co-Author: Felipe Beluche Lima, Alleima AB

Abstract: Brazil is the largest producer of crude steel in the Americas by BOF process, and many challenges come along with the increasing market demand. In the BOF, a tubular wall hood structure has been showing premature failures related to the overlay welded tube technology in the hood wall. The main root causes were: thermal fatigue at 1800°C, hot spot formation, high heat-affected zone (HAZ) leading to stress cracking susceptibility, carburizing corrosion, and superficial wearing. Based on that, co-extruded tube technology (named composite tube) was the alternative chosen to enhance hood performance without compromising the BOF process. To rises safety and productivity, the composite tube has a 100% metallurgical bond assuring stable expansion, high heat exchange efficiency, better corrosion resistance, and less rough surface finishing. It was highly suggested to many other mills due to similar and existing reported cases. The paper describes the product co-extruded composite tube and the first successful installation in a tubular wall hood of a BOF. Keywords: BOF Hood; Co-extruded composite tube; Corrosion

Prof. Pinkwart, Karsten, Member of the Hydrogen Council of the German Government, University Karlsruhe, Germany

Abstract: Climate change needs them and their industry to play a decisive role in stopping it, otherwise we will meet again under water. No joke, because only 0.1 degrees more global temperature increase means a rise in the world's oceans of 7 metres and you can imagine what this will result in. With a share of about 4% of anthropogenic CO2 emissions in Europe and 9% worldwide, the massive use of coal in the steel industry contributes to this. It must and is the goal to tackle an industry-wide conversion to green hydrogen. However, it is already clear that this technological change will require gigantic amounts of solar and wind energy. But it also requires corresponding infrastructures and ultimately also investors and financing possibilities, to list just a few of the points on your wish list. However, this is the only way forward, so let us discuss openly how we can succeed together.

Placier, Emmanuel, AMI Automation, Czech Republic

Co-Author: Emmanuel Placier, AMI Automation • Saul Gonzalez, AMI Automation • Jesus Andrade, AMI Automation

Abstract: Since the introduction of Off Gas analysis instrumentation in the Electric Arc Furnace, different applications have been developed using this information to improve the process efficiency and safety. Using the CO, CO2, temperature, and flow of the gas, the AMI SmartFurnace modules for Chemical Energy optimization calculate the optimal setpoints of the EAF burners and lances. The chemical energy modules are complemented dynamic process models and algorithms for electrical energy providing an integral furnace control of the Oxygen, Natural Gas, and Carbon Injection, as well as continuous raw material feeding. Using artificial intelligence, the Abnormal Water Vapor Detection module uses the gas temperature, flow, and water vapor content to identify unexpected sources of water in the off-gas which could pose a potential safety hazard, distinguishing it from the normal amount of water present in the furnace environment. Finally, the efforts to reduce emissions in the steel industry require accurate and reliable measurements of CO2. Understanding the influence of different conditions such as raw materials, melting profiles and practices, plays a major role in defining strategies to lower the environmental impact of the production. The latest implementations of this technology in plants with a wide range of raw materials, EAF mechanical characteristics, and production needs are described in this paper, and the achieved results.

Plattner, Tobias , Primetals Technologies Austria, Austria

Co-Author: Alexander Fleischanderl, Primetals Technologies Austria • Robert Neuhold, Primetals Technologies Austria

Abstract: "For a green steel production the environmental requirements are rising and ever stricter regulations by governmental institutions require lowest emission levels and utilization of by-products for existing and greenfield iron- and steelmaking plants. The dry gas cleaning technology (MEROS®) reduces the emissions of dust, SOx, NOx, heavy metals and dioxins from agglomeration plants, like sinter or pelletizing plants, safely below the required emission levels. Such low emission levels are maintained by a multi-component additive injection upstream of a high-performance fabric filter. Residues and by-products arising from the gas treatment are often disposed, leading to consumption of valuable landfilling volume and high cost as such material has to be stored under special conditions to avoid uncontrolled leaching of salts and heavy metals. The innovative by-product leaching process is closely linked to the MEROS plant and minimizes on site the residue volume. After the leaching step, the suspended solid like iron oxide will be utilized to the primary process. The brine will be treated in a series of wastewater treatments steps which are designed as a modular system. These treatments steps ensure the compliance with the most stringent discharge emission limits prior to the release of the clean brine into the sea. As an alternative for plants which are not located close to the sea a desalinization step can be installed and product (salt) can be gained by crystallization. How the MEROS and the Leaching technology can fulfill the environmental targets for a green steel production, shall be illustrated based on the latest results achieved with the MEROS systems installed at a plant in Italy and a Leaching plant, realized downstream a MEROS plant in Japan"

Pomaro, Paula, Vetta, Brazil

Co-Author: Lis Soares, Vetta • Thiago Maia, Vetta

Abstract: Seeking to meet the environmental agreements and climate conventions, a lot of effort and resources have been made to decarbonize industrial sectors. The steel sector alone is responsible for 7% of global emissions and 5% of emissions in Europe. However, besides the energy crisis, base industries in Europe are facing unfair competition with industries from countries that do not have the same level of ambition in climate matters. Despite the huge challenge, key factors are helping to drive the transition towards carbon-friendly steel products and maybe the most powerful and effective aspect is the change in customer requirements. There is an increasing trend in the steel-consuming industries, such as the automotive industry, of eliminating carbon emissions from their entire value chains and these customers are even willing to pay more for the steel produced under reduced emissions. In order to help steel industries to manage their emissions and create added value by differentiating their products, Vetta®, an SMS group company, has developed a digital solution for the management of emissions. This work presents Viridis Carbon, a digital solution for the management of gaseous and particulate emissions applied to the steel industry, from scopes 1, 2, and 3. The tool is able to issue reports on CO2 and GHG emissions in real time, generating transparency for stakeholders, policymakers, and competent authorities for taxation. It is also capable of tracking the emissions generated by each billet of steel produced, issuing emission certification seals, which makes it possible to differentiate products and increase added value for an increasingly demanding market with environmental commitment.

Ponten, Heinz-Josef, PSI Metals GmbH, Germany

Co-Author: Rudolf Felix, PSI Fuzzy Logik & Neuro Systeme GmbH • Sebastian Grob, PSI Metals GmbH

Abstract: There is no doubt that high-quality steel is indispensable in today's industrialized society, and steel producers have always been confronted with the dilemma of meeting the market requirements for new and thus more complex steel grades in an economically attractive way. A further dimension, the obligation of the steel industry to transform to carbon-neutral and more energy-efficient production, is added, which is becoming a tightrope walk due to the current situation on the energy markets. So how can steel producers optimize production processes, manage their heat schedules, save energy, comply with CO2 regulations and stay competitive with changing market demands? This paper discusses how collaborative smart software helps to optimize energy usage and hence influences CO2 reduction targets while minimizing production and material costs. An Online Heat Scheduler creates a detailed work schedule for all planned heats, including all required treatment and transport steps, their durations, the assignment of required production facilities and operating equipment as well as forecasts for required energy and material demands. Furthermore, it secures the required throughput and eliminates unpredicted discontinuity or sequence interruption at the caster line in case of unplanned standstills or delays. This process ensures efficient process quality by means of intelligent data collection, analysis and balance between target and criteria conflicts. Our approach is a proven industry standard, which helps plant managers flexibly manage planned downtime/maintenance work, plant problems, Hot Metal, DRI or Oxygen availability, Electrical Energy demand forecast and usage which leads to significant reduction in energy consumption and costs. Keywords: Decarbonization; Energy; CO2-Emission; Forecast; Qualicision; Heat Scheduling; Shopfloor

Pousette, Hedda, SSAB AB, Sweden

Co-Author: Joel Carlsson, SSAB/HDAB • Niklas Kojola, SSAB AB • Pär Ljungqvist, SSAB/HDAB • Liviu Brabie, Swerim AB • Ulf Sjöström, Swerim AB • Erik Sandberg, Swerim AB • Magnus Heintz, Swerim AB • Xianfeng Hu, Swerim AB

Abstract: The global climate crisis demands that CO2 emissions are reduced. This is especially the case for the steel industry, which contributes to 7% of annual CO2 emissions. Steelmaking using an Electric arc furnace (EAF) and hydrogen reduced Direct Reduced Iron (DRI) as iron input is a possible replacement for the blast furnace steelmaking route. All research work has been conducted within the Hybrit development project, a joint venture between SSAB, LKAB and Vattenfall. For steel production in the EAF, carbon-sourcing materials (typically anthracite and carbon in the steel scrap) play an important role as an alloying agent, a slag foaming agent, and a reducing agent. Biocarbon is investigated as a possible replacement for anthracite in order to eliminate fossil CO2 emissions during the melting of H-DRI in the EAF. This paper highlights development results from the Hybrit development program with focus on the application of biocarbon during the melting of H-DRI in a pilot scale EAF. The performance of several different biocarbon materials was evaluated in terms of carbon yield in the steel, slag foaming behavior, off-gas and dust compositions. Fixed carbon content, ash, and volatiles have varied between the tested biocarbon materials. Size and form have varied as well. The results show that biocarbon is a feasible replacement for anthracite. However, properties of the biocarbon have a significant impact on its performance during EAF steelmaking. This is an important aspect for the continuing development of a fossil-free steelmaking value chain.

Preisser, Nikolaus, Montanuniversität Leoben , Austria

Co-Author: Gerald Klösch, voestalpine Stahl Donawitz GmbH • Julian Cejka, Montanuniversität Leoben • Kathrin Thiele, Montanuniversität Leoben • Susanne Katharina Michelic, Montanuniversität Leoben

Abstract: The role of non-metallic inclusions has become more prominent with increasing demands on the mechanical properties of modern steels. The control of their amount, size, morphology and chemical composition is the key for producing highly advanced steel grades. Interactions between steel and slag essentially influence inclusion evolution over the production process and, therefore, the final steel cleanness. Recently, research on the role of alkali oxides on inclusion behavior in secondary metallurgical treatments increased, especially controlling inclusion scenarios in very cleanness-sensitive steels. This study analyses inclusion behavior and modification in medium carbon steel in contact with low-basicity pseudo-wollastonitic slags with additional contents of alkali metal oxides. In particular, their capability to remove or affect non-metallic inclusions was analyzed. Thermodynamic calculations showed that adding R2O (R=Li, Na, K) can drastically lower the melting point of the slag. As slag and non-metallic inclusions interact, the particles' chemical composition is influenced. As a result, inclusion deformability improves. High-Temperature Laser Scanning Confocal Microscopy and Tammann Furnace experiments were used to study inclusion evolution through their interaction with slag with different amounts of alkali oxides on a laboratory scale. The inclusion population was compared before and after steel-slag interaction using automated SEM/EDS analysis. Particles modified with the added alkali elements could be observed, as well as a shift in the overall inclusion population. Thermodynamic calculations show significant changes in the liquidus temperature of the modified inclusions and a strong dependency on the ratios of Na2O/Al2O3 and Na2O/SiO2.

Presoly, Peter, Montanuniversität Leoben, Austria

Co-Author: Daniel Kavic, Montanuniversität Leoben • Christian Bernhard, Montanuniversität Leoben • Susanne Hahn, Primetals Technologies Austria • Sergiu Ilie, voestalpine Stahl GmbH

Abstract: Modern steel grades are subjected to constant development to perform weight reduction, energy-saving, and automobile safety performance. In the last decades, high strength and ductile steels were developed with increasing quantities of silicon and manganese. Three of these alloying concepts are Dual-Phase (DP), TRansformation Induced Plasticity (TRIP) and even TWinning Induced Plasticity (TWIP) steels. All these steel grades are based on the iron-carbon-manganese system with additions of ferrite former such as silicon and/or alumina, followed by micro-alloying elements. The main difference compared to previous steel grades are the significantly higher levels of ferrite formers. Apart from the research on these new steels' material and product properties, the knowledge about the production process, particularly the continuous casting (CC) and the initial solidification in a water-cooled copper mold, is of significant importance. In this regard, the high-temperature phase transformation temperatures and the thermodynamic properties play a particular role. An efficient pre-identification of hypo-peritectic steel grades by experiments or thermodynamics is relevant to ensure surface quality, productivity, and operational safety in the casting process. The potential of different laboratory experimental methods and thermodynamic approaches is critical evaluated in comparison with operational experience from voestalpine Stahl Linz. Since process data in the continuous casting process often overlap with different operating influences (e.g. casting speed changes, width adjustments…), a new approach is presented to identify the process behavior of peritectic steels without additional effects. For this purpose, operating data from the mold monitoring were processed statistically, and only data areas with a steady-state casting length of more than 100 m were used for further consideration. Using this data preparation method, the peritectic area in the continuous casting process can be clearly described. Statistically prepared process data and experimentally verified thermodynamic data are the basis for the development and validation of demanding process models.

Pronk, Hans , Tata Steel IJmuiden B.V. , Netherlands

Co-Author: Cees Brockhus, Tata Steel IJmuiden B.V. • Sander Willemsen, Tata Steel IJmuiden B.V. • Dennis Berkvens, Tata Steel IJmuiden B.V.

Abstract: Automation of processes in steel making are difficult and risky because of the high potential risks when mistakes in programming are made. To secure safe and stable automation you need time consuming test on the equipment/machines involved. In case of automation on production critical equipment, testing time will lead to loss of production. In Tata Steel Ijmuiden BOS plant the middle loading crane for hot metal or scrap is the most production critical compared to other cranes, so we decided to build a digital twin for this crane to speed up automation. This digital twin behaves exactly as the real crane and is connected to the backup PLC of the crane with the same software as in the real crane. With this digital twin we can test new software in a 3D environment before we install it on the real crane. Automation of these cranes can speed up without loss of production. Automation and operator skills are linked to each other. 99% of the time the automation will work but when it not works the operator need the skills to do it manual. For simple tasks it is not a problem but for complex tasks like charging hot metal in a vessel without fume emission or spilling hot metal it is more difficult. Another problem is to get operators working in a steel plant and to train them on the job with a mentor. The work done to create a digital twin for software development and testing is the base of the next step, a loading crane simulator for operator training. In Tata Steel Port Talbot there is already an simulator in operation and also other steel plants (not Tata) started with Steel Sim VR for training crane operators.

Purohit, Suneeti, Swinburne University of Technology, Australia

Co-Author: Mark Pownceby, Commonwealth Scientific and Industrial Research Organisation • Akbar Rhamdhani, Swinburne University of Technology • Isis Ignacio, Swinburne University of Technology • Geoffrey Brooks, Swinburne University of Technology

Abstract: Magnetite ores have the significant advantage of being able to be easily concentrated via magnetic separation, which is now becoming even more important as there is general shift towards DRI processes away from Blast Furnace ironmaking. For many DRI processes, any gangue in the ore is retained in the product, which is expensive to remove via electric melting, so minimising gangue in the ore is an economic priority. In the current ironmaking technologies, it is common to prepare magnetite ores for processing by firstly oxidising to hematite during pelletisation and sintering. This oxidation is carried to improve the reducibility of the iron ore for the subsequent ironmaking process. This improvement in the kinetics comes at a cost in terms of CO2 generation and/or consumption of Hydrogen (an expensive reductant). It is estimated that up to 130 kg of CO2 could be saved by not oxidising magnetite if the issue of reducibility could be addressed. Researchers at Swinburne University of Technology, in collaboration with CSIRO, has been studying how to improve the reducibility of magnetite ore by combining magnetite with lime and measuring the subsequent physical properties and reducibility. Lime is required in the steelmaking process, so introducing lime in the agglomeration step should not necessarily add cost. Substantial testing under laboratory conditions of different combination of magnetite with lime and other gangue oxides (alumina and silica) to form both pellets and sinter have shown that addition of lime (up to 7 wt.%) can significantly increase the reducibility of magnetite without sacrificing important mechanical properties required for subsequent ironmaking operations. Studies using Hydrogen as a reductant, have come to similar conclusions. This paper will summarise the key findings of this work and explore how these findings could be commercially exploited.

Qayyum, Faisal, Technische Universität Bergakademie Freiberg, Germany

Co-Author: Ulrich Prahl, Technische Universität Bergakademie Freiberg • Seigfried Schmauder, University of Stuttgart • Sergey Guk, Technische Universität Bergakademie Freiberg • Ali Cheloee Darabi, University of Stuttgart

Abstract: This study aims to investigate the effect of chromium and molybdenum on the formation of pearlitic microstructure in 1% carbon steels. To obtain experimental data, 12mm wires of one benchmark (Fe-1C) and two trial alloys (Fe-1C-1.5Cr and Fe-1C 1.5Mo) are manufactured in-house by casting and hot caliber rolling. These wires are homogenized at a temperature of 1200°C for a holding time of 12 hours. MatCalc and JMatPro software are used to identify the time-temperature and transformation curves for each alloying system. The effects of transformation times and holding temperatures on the pearlite morphology in each alloying system are systematically analyzed and compared by examining the resulting microstructures under an electron microscope. The microstructural features such as lamella length, lamella thickness and inter-lamella spacing for each case are quantitatively analyzed by post-processing the image data using FiJi-ImageJ and Python scripts. The probability and cumulative distribution plots of the microstructural features allow for the comparison and selection of optimal process routes for obtaining similar pearlitic microstructures across all alloying systems. Furthermore, a phase field simulation is performed to find an optimized heat treatment. The accuracy of the phase field models is validated through experiments. The heat treatment routine for pearlite formation in all three steels is simulated using the MICRESS software and the resulting microstructures are compared with the experimental results. To reduce computational cost, the heat treatment simulations are started from the fully austenitic microstructure and the morphology for this condition is calculated using MatCalc software. The pearlite formation heat treatment is simulated and the thermodynamic parameters are extracted using MatCalc software and literature. With the validated models, microstructures under different heat-treatment processes can be predicted and an optimized heat-treatment condition for all three materials can be obtained.

Rahmatmand, Behnaz, University of Newcastle, Australia

Co-Author: Nicholas Ong, University of Newcastle • Kim Hockings, BHP Group • Salman Khoshk Rish, University of Newcastle

Abstract: The reduction of CO2 emissions from blast furnace operations has received much attention in recent years. The introduction of hydrogen into the furnace is considered a promising solution for reducing the carbon intensity of blast furnace ironmaking. Although the substitution of pulverized coal and coke with hydrogen reduces the overall fuel rate, this can alter the thermal and chemical state inside the furnace, which in turn influences the reaction rate and the degradation mechanism of coke. This study investigates the impact of hydrogen injection and coke quality on coke gasification reactivity and kinetics. A high temperature thermogravimetric analyzer was used to study the CO2 and H2O gasification behaviour of coke lumps with CSR of 43.11 and 68.32 in the temperature range of 900-1200 °C. Three kinetic models, i.e., volumetric, random pore, and shrinking core, were used to explain the gasification behaviour. The shrinking core model was found to better fit the experimental data and was thus applied to calculate the gasification rate and to determine the reaction controlling mechanism. Coke reaction rates with H2O were up to 8 and 5 times greater than CO2 for low and high CSR cokes, respectively. Coke reactivity with H2O in the entire temperature range was found to be controlled by the interfacial reaction, while the reactivity with CO2 was controlled by both interfacial and diffusion which depended on the reaction temperature. The activation energy of coke gasification with H2O was up to 65% lower than that of CO2. However, this decrease was less pronounced for the high CSR coke, suggesting that a higher quality coke is required to mitigate the fast degradation of coke during reaction with steam.

Rajabi, Ahmad, VDEh-Betriebsforschungsinstitut GmbH, Germany

Abstract: Growing customer expectations together with increasing availability of relevant information and high flexibility of final product features are taking established Decision Support Systems (DSS) performing automatic release decisions continuously to their limits. Emerging machine-learning technologies could solve this problem, but concepts for their robust industrial application performing high-stakes decisions are missing. This paper aims to report our attempt to improve the automatic quality assessment of steel products by means of a holistic approach combining deep learning technology with sophisticated management of underlying training data to enable the optimal use of all available data sources and simultaneously simplify the configurability and maintainability of previous DSS.

Ramalingam, Sethu, Danieli Corus B.V, Netherlands

Co-Author: Peter Klut, Danieli Corus B.V

Abstract: Blast furnace top gas contains dust particles which are removed in two stages in order to use it further as fuel gas. Coarser dust particles are removed in the first step using gravity or cyclone dustcatchers and the finer particles are removed in the second step (dry bag filter). The temperature in the first step should be in the range of 115°C to allow optimum separation efficiency and avoid condensation of moisture. For the secondary cleaning, the temperature window is narrow that it shall neither damage the filter bags nor the gas loses its calorific value, requiring a conditioning tower in-between to cool the gas in case of surges of hot gas. The top gas is transported to the gas cleaning plant via various refractory pipes (offtakes, uptakes, downcomer and raw gas main). Hence the choice of the insulating refractory is critical for the smooth and optimal performance of the entire gas cleaning process. In this study the effect of GCP refractory is investigated through series of three-dimensional CFD models using commercial software Ansys Fluent. The physical refractories and the steel shells are included in the flow model enabling conjugate heat transfer (CHT) from the hot gas to the solid walls. As the flow field and boundary layers are predicted in better fashion the heat transfer coefficients are predicted near accurately in CFD. Performance of the refractory is studied through steady-state calculations but during blast furnace operations a peak in the gas temperature occurs for short period of time, which are analyzed through series of transient state calculations. The solid wall time scales are too low bottlenecking the computation time, which is tackled by several modelling techniques. Eventually the model is validated with an overheating (of the refractory) incident that occurred recently at a blast furnace.

Ramirez Lopez, Pavel E., Swerim AB, Sweden

Co-Author: Anton Sundström, Swerim AB • Joakim Eck, Swerim AB

Abstract: Steelmaking processes occur at high temperatures (in excess of 1500° C) which makes experiments and measurements on liquid steel very difficult. A good alternative to model the behaviour of liquid steel is to use low-melting point alloys with similar density and viscosity (for example: Bi-Sn, Tmelting: 150°C). SWERIM is home to one of the most advanced facilities for physical modelling with liquid metal for casting in the world. This facility is used as benchmark to test flow control devices such as nozzles, stoppers and sliding gates during continuous casting operations. The present manuscript describes recent work to increase the size of the simulator to full-scale for wide and thick slabs as well as reaching casting speeds and Argon flow rates equal to those applied in the Industry. The Simulator has been also equipped with a series of measurement techniques to monitor pressure, velocity, temperature, level fluctuations and vibration in order to fully characterize the metal flow in CC moulds. Finally, the present paper enumerates the main findings, challenges and limitations derived from extensive tests in the simulator with real ceramic nozzles/stoppers and their counterparts in stainless steel.

Rangavittal, Bharath, KTH Royal Institute of Technology , Sweden

Co-Author: Michael Vynnycky, University of Limerick • Björn Glaser, KTH Royal Institute of Technology

Abstract: Development of mathematical models which include complex multiphase flow, coupled with heat exchange and chemical reactions, is necessary for understanding the inner state of the blast furnace. In this work, a novel approach using asymptotic methods is developed to model the transient gas-solid flow behaviour in the blast furnace. This is done by reducing the earlier developed Euler-Euler models with scaling assumptions that are based on the fact that the residence time of gas in the blast furnace is usually smaller than that of solid by several orders of magnitude. Results from this reduced model yield gas and solid flow patterns inside the blast furnace. In parallel, another model is developed by combining Discrete Element Method (DEM) and Computation Fluid Dynamics (CFD) to precisely simulate the gas flow and solid motion in the blast furnace. A qualitative comparative study between velocity patterns obtained from both the models is carried out. It is believed that asymptotic modelling could possibly open the doors to a computationally efficient approach for predicting the inner state of the blast furnace.

Rasmussen, Thomas, Åkers Sweden AB, Sweden

Co-Author: Jonas Lagergren, SSAB AB • Stefan Wahlund, Union Electric Åkers • Johan Eliasson, Swerim AB • Hans Magnusson, Swerim AB

Abstract: A new High Speed Steel (HSS) concept for heavy-duty cast roll materials has been developed. Target was to develop a suitable casting and alloying concept to yield an optimized structure of the HSS material, but still using established production processes. More specifically, the current alloying concept needed to be modified so that unwanted phase transformation of softer phases, ferrite and pearlite, should be pushed to longer times, in order to reach the harder phases martensite and bainite upon cooling after austenitization. With guidance from computational thermodynamics different alloying concepts were studied by simulating continuous cooling diagrams (CCT), with interest on critical cooling rates and with respect to the available process window. To validate and confirm these alloying ideas, small scale laboratory ingots were produced, and industrial heat-treatments were simulated by dilatometry. From dilatation experiments and characterization, it was confirmed that the optimized alloying was able to push unwanted phase transformations to longer times, which resulted in improved mechanical properties. Different tempering trials were studied by varying double and triple cycles. Different tempering temperatures was then decided and evaluated by both hardness and impact testing. Based on small-scale laboratory work and the confirmation of alloying ideas, together with a suitable casting and modified heating concept, a full-scale Plate Mill Work Roll has been produced. This new HSS roll concept is now running in a hot plate mill, results are here presented.

Rauter, Wolfgang, voestalpine Stahl Donawitz GmbH, Austria

Co-Author: Michael Riedler, Primetals Technologies Austria • Franz Wimmer, Primetals Technologies Austria • Jürgen Reiter, voestalpine Stahl Donawitz GmbH • Werner Brandl, voestalpine Stahl Donawitz GmbH • Alexander Mair, voestalpine Stahl Donawitz GmbH • Mario Erker, voestalpine Stahl Donawitz GmbH

Abstract: "The new Bloom CC4 continuous caster in Donawitz, is currently the most modern plant of its kind worldwide and corresponds fully with digitalization and environmental standards. The fully digitalized system allows the finest control of the parameters in terms of purity and microstructure homogeneity and an expansion of the product portfolio to 9% alloy content. Rail steels, tubular steels, steels for cold forming, ball bearing steels, spring steels in ""Super-Clean"" quality are among these. Already the first produced blooms on this caster achieved excellent macroscopic cleanliness reducing rejection rate in rail production. Furthermore the CC4 allows a fully automated production process as well as fully automated manipulation and loading of blooms. The paper will present latest innovations and production processes, implemented at CC4 of voestalpine Stahl Donawitz GmbH and additionally quality results for different formats and steel grades are discussed."

Rèche, Delphine, VDEh-Betriebsforschungsinstitut GmbH, Germany

Co-Author: Christina Minari, Dimasimma Srl • Matteo Chini, Pittini S.p.A. • Denis Azzano, Pittini S.p.A. • Loris Bianco, Pittini S.p.A. • Stephan Lindemann, Salzgitter Flachstahl GmbH • Christian Clees, Multikopter.de • Peter Lundin, Swerim AB • Roberto Piancaldini, Rina Consulting – Centro Sviluppo Materiali S.p.A • Alexander Dunayvitser, VDEh-Betriebsforschungsinstitut GmbH • Kevin Sze, Swerim AB • Antonella Angrisani, Rina Consulting – Centro Sviluppo Materiali S.p.A

Abstract: Although the use of unmanned vehicles for industrial applications is discussed a lot lately, systems in operation can hardly be found in the steel industry and common knowledge in the plants about the specific capabilities of UVs is poor. The objective of ROBOINSPECT project is to introduce novel robotic inspection systems in the European steel industry. For this purpose, existing technologies based on unmanned vehicles (UVs) are assigned to inspection tasks and technological gaps are closed by further developments. The aims are to reduce downtimes and increase occupational safety. Unmanned aerial (UAV) and ground (UGV) vehicles are developed for semi-autonomous operation during running production in confined and hazardous areas, using custom indoor navigation concepts. Software is provided to accelerate damage analysis of facilities and processes as well as to detect online plant misalignments. In this project, different UV types are used and specifically designed for different types of inspection tasks to cover a wide range of inspection work in the European steel industry. A drone has been developed together with improved software to be able to carry out indoor inspections without using a GPS navigation system. Another use case which is studied in this project is the use of ground vehicle together with a robotic arm equipped with a specific camera system developed for automatic inspection purposes. In addition, for another use case, a video microscope has been developed to analyse dynamic displacements of plants during operation by subpixel amplification (for example during steel rolling application). Intelligent software for image analysis to handle large data streams of visual material generated by the UVs’ sensors are also examined and developed here. To conclude, the (UVs) will help in production to carry out inspection and maintenance tasks in order to ensure highest safety for personal as well as time and money savings.

Reiche, Thomas, Managing Director, FEhS-Institut für Baustoff-Forschung GmbH, Germany

Co-Author: David Algermissen, Head of the Secondary Raw Materials Department, Institut für Baustoff-Forschung e.V. • Andreas Ehrenberg, Head of Department Building Materials, Institut für Baustoff-Forschung e.V.

Abstract: The main challenge of the steel industry for the next decade is the steel production transformation process. The CO2 intensive blast furnace/BOF route will be substituted by a combination of Direct Reduced Iron (based on natural gas, later on "green" hydrogen) with an Electric Arc Furnace (EAF) or a Submerged Arc Furnace (SAF), heated with renewable energy. Thus, the well-known latent-hydraulic granulated blast furnace slag (GBS) being successfully used in cement and concrete since more than 140 years will vanish step by step! GBS is used as a supplementary cementitious material not only, but in particular due to its CO2 reduction potential in the cement/concrete production. Whereas the DRI process itself does not generate any slag, EAF and SAF will do. EAF and SAF slags will be very different. The reasons are e.g. the different oxidizing (EAF) or reducing (SAF) atmospheres and different shares of scrap input (EAF). Moreover, the new EAF slags will be also different compared to today's scrap based EAF slag. For example, the heavy metal content will be lower (but much higher compared to GBS). However, specific slag/metal ratios, slag volumes, chemical and mineralogical compositions and physical properties of the new slags are yet unknown. Thus, also their cementitious and environmental properties are still unknown! Different projects aim mainly to create slags being similar to GBS. The main objective is to offer furthermore a reactive material to the cement and concrete industry. The presentation gives an overview on the different approaches within the steel industry, main goals, main technical and legal challenges and some current FEhS projects. For example, "SaveCO2" - a project with thyssenkrupp Steel, HeidelbergMaterials et al. - is focused on the DRI/SAF route whereas "DRI-EOS" - a project with Salzgitter, Holcim et al. - is focused on the DRI/EAF route.

Reimer, Paula, Linz Center of Mechatronics GmbH, Austria

Co-Author: Jagoba Lekue, Linz Center of Mechatronics GmbH • Erik Parteder, voestalpine Grobblech GmbH • Andreas W. Nemetz, Johannes Kepler University • Thomas Kaltenbrunner, voestalpine Grobblech GmbH • Bodo Heise, voestalpine Grobblech GmbH • Stefan Falkner, voestalpine Grobblech GmbH • Thomas Gross, Linz Center of Mechatronics GmbH • Rupert Egger, voestalpine Grobblech GmbH • Klaus Zeman, Johannes Kepler University

Abstract: As accuracy requirements for tolerances of heavy plates are continually increasing, precisely tuned process control is indispensable. The aim of this work is to characterize the relevant thermomechanical effects on a heavy plate mill depending on the pass configuration. This was done by performing a parametric study with a high-resolution 2D Finite Element (FE) offline model of the roll gap. Particular attention was paid to thermomechanical coupling. As a cross-section of the heavy plate moves through the roll gap, its temperature distribution is influenced by the heat flow within the plate, the heat exchanged with the work rolls, the heat generated by plastic deformation as well as frictional dissipation at the interface between work rolls and heavy plate. The implemented FE model considers the described effects as well as the elastic flattening of the work rolls. It also contains temperature dependent material behavior, identified by laboratory measurements, and a limit for the transmissible frictional shear stresses as a function of the current yield stress of the rolled material at its contacting surface. The calibration of non-measurable parameters like heat transfer coefficients and friction coefficients was accomplished based on a broad spectrum of measurement data extracted from the process. By incorporating all relevant physical phenomena, the employed FE model represents a benchmark for the prediction of the roll separating force, the roll torque, and the temperature distribution over the plate thickness. The results of the parametric study indicate which thermodynamic effects dominate in which area of the parameter range. Furthermore, they help to improve the overall comprehension of the system and open the door to the condensation of the model to a reduced online model that allows the calculation of one pass within milliseconds without substantial loss of accuracy.

Reinisch, Niklas, RWTH Aachen University, Germany

Co-Author: Tarik Viehmann, RWTH Aachen University • David Bailly, RWTH Aachen University • Gerhard Lakemeyer, RWTH Aachen University • Gerhard Hirt, RWTH Aachen University

Abstract: In recent years, many production processes, including open-die forging, have been digitalized, resulting in process data and process knowledge being available in many places. However, this knowledge is often decentralized, e.g., in individual companies, and cannot be consolidated in one database easily due to stakeholder interests (secrecy, ownership, etc.) or the volume of data. In order to nevertheless draw added value from all available process data, a multi-agent system (MAS) is presented using the example of an open-die forging. Based on an ontology, the individual agents can communicate semantically with each other to exchange information. A top-level service broker manages the available services and forms the link between agents and user interface. In this manuscript, a MAS-demonstrator is presented that provides two example services, the material choice of a forging as well as the design of an optimal pass schedule. For this, the MAS uses process data along the production chain of an open-die forging as well as an ontology designed to represent this production related data. In the MAS multiple agents are included, representing different stake holders along the production chain like the steel retailer, the steel producer and the open-die forge.

Ribeiro Gomes, Milena Amábilis, RHI Magnesita GmbH, Austria

Co-Author: Lukas Konrad, RHI Magnesita GmbH • Antoine Ducastel, RHI Magnesita GmbH • Taco Janssen, RHI Magnesita GmbH

Abstract: In the steelmaking industry, the largest share of CO2 emissions comes from the reduction of iron ore. A switch from the blast furnace (BF)/basic oxygen furnace (BOF) route to the direct reduced iron (DRI) process with natural gas followed by the electric arc furnace (EAF) already enables CO2 savings of up to 38%. However, in order to meet the mid- to long-term CO2 targets of the iron and steel industry, further measures are required. Most DRI plants are currently operating on natural gas, which results in approximately 60% hydrogen in the process gas. However, currently projects are underway to determine if DRI units can operate at hydrogen levels at or close to 100%, which could further reduce CO2 emissions by more than 80%. In this context, it is important to consider the impact of hydrogen on the refractory lining in the DRI shaft kiln. Previous studies have shown that hydrogen can permeate through refractories and reduce ceramic oxides under certain process conditions. Silica-containing materials are reported to be especially susceptible to hydrogen attack. However, a deeper understanding of corrosion mechanisms is still needed. This article presents the first results of modelling and experimental work carried out by RHI Magnesita on the impact of hydrogen on refractory systems. Investigations were conducted regarding the thermodynamics and kinetics of ceramic oxide reduction by hydrogen as well as the effect of hydrogen exposure on the microstructure and properties of refractories. This enables refractories to be identified that are suitable for lining a DRI shaft kiln where hydrogen is used as a reductant and supports the development of novel hydrogen-resistant refractory solutions.

Richard, Sebastian , SMS group, Germany

Co-Author: Matthias Krüger, SMS group • Karsten Rues, SMS group • Christoph Helle, SMS group

Abstract: In cold rolling mills vibrations of mechanical parts and/or strip can interfere several quality parameters like thickness, shape or surface quality. Since vibrations tend to occur at higher speeds, the rolling speed of single- or multi-stand mills for steel and aluminum has to be limited quite often. Among other mechanisms at cold rolling mills the so-called 3rd Octave and 5th Octave Chatter are the most important vibration issues. They are introduced by explaining related mechanisms and showing results of operational measurements. Subsequently some well-known measures against chatter issues and their consequences are listed and explained, like online Chatter monitoring with Auto-Slow-Down (ASD-) functionality. After giving a general survey about vibration issues in cold rolling mills and related conventional counter measures, the paper focusses on the development of SMS group to counteract 3rd Octave Chatter. The so-called X-Pact® Active Chatter Damping (ACD) uses Piezo electric elements as actuators which are located in an actuator box placed underneath the bottom backup roll chocks of a mill stand. A first pilot unit was put into operation in 2017 in a four-stand aluminium tandem cold rolling mill from SMS group. The optimization of the system and its integrated force measurement, including related tests and improvements to the mechanical design, was completed by April 2018. Permanent operation of the system is ongoing until today. The paper provides an overview of various operating results of the system during its normal operation. These are showing the reduction of vibration amplitudes and the increase of rolling speed with an active system. Beside of this, also the behavior of the system in the context of different vibration and excitation mechanisms is shown by practical examples. The parallel product development, with focus on product series implementation and improvements regarding performance and durability, is already applied in the actually sold applications.

Richardson, Andrew, Liberty Speciality Steels Ltd, United Kingdom

Co-Author: Howard Watkins, Liberty Speciality Steels

Abstract: Liberty Speciality Steels operates a Vacuum Induction Melting (VIM) facility to produce high-performance iron and nickel-based alloys for applications in the aerospace and auto-sport industries. The paper describes process development work designed to minimise the incidence of spout skull build-up, the accumulation of solidified metal within the crucible pouring spout during ingot casting. Skull build-up must be manually removed after pouring of the heat, which requires unnecessary breaking of the vacuum between melts and leads to operational delays. A bespoke thermal model has been developed to help identify potential root causes of spout skull formation. Model simulations with the initial VIM power profile (kW as a function of crucible tilt angle), indicated that the pour stream temperature can fall below the solidus towards the end of pouring resulting in skull build-up. A revised power profile was devised, with the aim of maintaining a constant pour stream temperature. It was recognised that this could impact the solidification dynamics in the ingot head and the formation of the shrinkage cavity. A series of casting-simulations was carried out using the Magmasoft 3D package to determine the sensitivity of shrinkage-cavity size and depth to final pour stream temperature. Simulations for a constant pour stream temperature indicated a small decrease in the extent of pipe-cavity compared with the cooling pour stream situation. Predicted changes to cavity depth for different power profiles were judged to be insignificant. Measurements of cavity depths from sectioned ingots showed close agreement with model predictions. Production trials were undertaken across a range of alloy grades, using various power profiles designed to maintain a more constant pour stream temperature. Significant reductions in the extent and frequency of skull accumulation in the pouring spout were achieved, with associated reductions in operational downtime.

Richaud, Johan, Vesuvius Europe, France

Co-Author: Anupkumar Nandakumar, Vesuvius India Limited • Soumya Bhattacharjee, Vesuvius India Limited • Rajkumar Gangadharappa, Vesuvius India Limited • Murali Sabhapathy, Vesuvius India Limited • Ganesh L, Hospet Steels Ltd. • Manoj Gupta, Hospet Steels Ltd. • P.L Satish, Hospet Steels Ltd. • Atluri Ratnaprasad, Hospet Steels Ltd.

Abstract: The production of Re-Sulphurized steel, and other clogging prone grades is a challenge in terms of limited sequence length thus impacting both productivity and sustainability. The efficient production of these grades requires optimized tundish vessel functioning, which has historically been addressed through shaping tundish furniture -impact pad like. Turbostop® pad, dams, weirs and baffles. The design of these refractory components has shown significant impact on steel cleanliness in continuous casting. Tundish to mold steel can also be further improved by modifying flow controlling refractory designs like the stopper. In long product casters, generally argon injection through the stopper nose into the casting channel is avoided to prevent observed boiling in mold, which can cause operational and quality issues. This paper describes the improvement in the flow performance from the tundish to mold. The novel stopper design of Multi-Channel Argon injection through the stopper nose resulted in reduction in clogging occurrences near the stopper regulating surface and the SEN seat. This helps in achieving a stable stopper position throughout the tundish sequence and leading to a significant reduction in the rate of stopper rise required for extended sequence casting. Multiple trials were successfully carried out showing reduction in stopper rise rate as well as reduction of stopper flushing counts compared to conventional stopper design. Thanks to the stopper rise rate reduction, the sequence length could be extended from 2 heats/Tundish to 2.91 Heats/Tundish in average, thus improving productivity and caster yield leading to cost reduction and sustainability improvement - reduced tundish consumption, lower fuel costs. Additionally with this new stopper design quality of the final product also improved.

Richaud, Johan, Vesuvius Europe, France

Co-Author: Sudip Banerjee, Vesuvius India Limited • Paromita Sarkar, Vesuvius India Limited • Roshan Ughade, Vesuvius India Limited • Kamruz Zaman, Vesuvius India Limited • Nagarjuna V L, JSW Dolvi • Sameer Patil, JSW Dolvi • Anil Gargi, JSW Dolvi • Neelesh Pande, JSW Dolvi • Sanjay Gurme, JSW Dolvi

Abstract: Recent thin slab caster performance enhancements at JSW Dolvi Works with a clear focus to cast long sequences of higher quality grades produced at higher casting speeds, leading to higher throughputs have been possible with the application of the ElectroMagnetic Brake (EMBr). Along with this implementation, the increase in productivity has implied extension of the caster utilization time by reducing the process down time, the major portion of the process downtime is the regular sequence change time. To achieve these challenging conditions, the tundish and mold flow behaviour have been characterized and optimized along with implementation of higher refractories performance related to both their design and their material selection. Extensive numerical and physical simulations have been conducted to determine the different measurable parameters for tundish and mold flow improvements. Increased minimum residence time, improved inclusion floatation and turbulence reduction, better thermal homogeneity in tundish have been obtained after re-designing the internal tundish geometry. A new SEN producing stable meniscus flow and optimal mold temperature distribution allowing longer sequence to be cast in a thin slab caster. In addition to these refractory enhancements, JSW-D has significantly improved their casting parameters and stabilized the processes involved. Due to better co-ordination between the steelmaking & casting shop the casting speed fluctuations have been reduced and higher speeds of over 5.5 m/min corresponding to higher throughputs of above 4 tons/min have been realized on a consistent basis. Stable casting conditions have resulted in better refractory performance. The sequence length has increased by 15% on an average resulting in increasing the productivity of the shop with less unexpected stoppages or reduced numbers in slowdowns. Sustainability improvement has been achieved by increasing the number of heats/tundish and consequently the overall refractory consumption per ton of steel cast as well as the required energy have been reduced.

Richaud, Johan, Vesuvius Europe, France

Co-Author: Anil Kumar Rauta, Vesuvius India Limited • Akanksha Kumari, Vesuvius India Limited • Krushna Chandra Panda, Vesuvius India Limited • Murali Sabhapathy, Vesuvius India Limited • Thayappa Hosahali, JSW Vijayanagar • Sankar Ananthan, JSW Vijayanagar • Anil Kumar, JSW Vijayanagar • K. Ravi Shekar, JSW Vijayanagar

Abstract: The CRNO steels are mainly used as core materials in electrical motors and transformers as they are the group of electrical steels with Isotropic Magnetic properties, meaning magnetic properties are practically same in all directions of magnetization in the plane of material. The essential magnetic properties requirement for these steels are low core loss values and high permeability. Thin gauge, clean steel and optimum grain size are required to achieve the desired magnetic properties in CRNO steels. Electrical steels with Si ranging less than 1% showed significant variation in permeability (B50), where it varied from 1.69 to 1.77 T and average core loss value was 5.48 (W15/50). Since the permeability and the core loss depends on the steel cleanliness detailed investigation was carried out to find the factors primarily influencing it, and it was found that the presence of inclusion size above 10 μm resulted in lower permeability and higher core loss. Hence in this grade use of Tundish Gas Diffuser (TGD) and an Inert working lining (OBL™) was experimented for forced flotation of inclusions through argon bubbling inside the tundish and to prevent generation of inclusion by reaction of the steel with the tundish working lining. Extensive numerical and physical simulations have been conducted to determine the position and the flow of argon thru the TGD. Average inclusion size reduced from 12 μm to < 8 μm in HR coil with the use of diffuser and the inert working lining. The permeability variation has reduced from 0.08T to 0.05T (i.e 1.72 to 1.77 T) and the Average core loss value reduced to 5.32 (W15/50). In addition to these refractory enhancements, JSW V has significantly improved and stabilized the various processes involved from steel making to casting.

Richter, Gerhard, ONEMET Technology Trading GmbH, Austria

Co-Author: Xavier Rafael, Groupe IMCG SAS • Thierry Marlot, Groupe IMCG SAS

Abstract: To reliably prevent material defects occuring in the course of downstream production processes such as e. g. hot rolling, cold rolling, etc. as well as in the final product, a corresponding treatment of the surfaces of the starting products like continuously cast slabs, blooms or billets is essential. While in the past cracks and other surface defects were mostly removed by means of scarfing, high-pressure grinding has now established itself as the superior technology for this purpose. Thanks to a controlled, even material removal (only as much as necessary, also on curved products) without any thermal impact on the material structure, no material losses due to the possibility of collecting the chips resulting from grinding by alloy and to recycle them, the environmental friendliness of the process (fossil-free, no CO2 emissions, clean exhaust air by filtering-out residual dusts which can also be recycled, etc.), as well as the excellent quality of the ground surfaces and high throughput capacity that can be achieved, high-pressure grinding is superior compared to scarfing but also milling. In order to ensure optimum operating results reliably and cost-effectively, a state-of-the-art grinding equipment tailored to the specific application and a profound user know-how for the grinding operation are necessary. Both can be guaranteed by Groupe IMCG as a specialized manufacturer and supplier of top-quality grinding machines (which also allow the utilization of the data and coordinates of surface defects detected beforehand by inspection systems for an automated flaw grinding) and experienced provider of conditioning services to the steel and special metal industries. As described in this paper, Groupe IMCG has also developed a powerful material data management system that allows all important material and process data to be acquired in real time and subsequently evaluated for process optimization and reporting purposes.

Riedler, Michael , Primetals Technologies Austria, Austria

Co-Author: Gerald Hrazdera, Primetals Technologies Austria • Thomas Lengauer, Primetals Technologies Austria • Josef Watzinger, Primetals Technologies Austria • Denijel Burzic, Primetals Technologies Austria

Abstract: "In order to maintain a sustainable planet for our children, the objective of decarbonization is drastically reducing carbon dioxide emissions. In the steel industry this leads to the replacement of classical BOF production as well as a change in raw material towards HBI and DRI. This changed process routes confront continuous slab production with new challenges. While liquid steel input is changed in composition and residual elements, cast products have to maintain the same quality level as expectations on final product remain unchanged. These challenges require new, flexible sensors and actuators integrated into the continuous slab caster. In addition to the support provided by advanced automation systems, this includes, among other things, an increasingly fine setting of the casting gap and the application of innovative cooling practices, as well as an active flow control through electromagnetic actuators. In terms of immediate adaptation to the changing requirements, these systems and actuators should be selected in such a way that they can be integrated also into existing continuous casting machines. This article discusses successfully implemented systems in process routes with non-BOF steel production in combination with continuous casting plants."

Riethof, Sebastian, thyssenkrupp Steel Europe AG, Germany

Abstract: The Climate change, which is becoming increasingly evident, has an impact on our plants worldwide. Temperature-sensitive processes in particular are significantly impaired by the longer periods of hot weather. Higher cooling capacity is becoming unavoidable for constant production. The raw coke oven gas (COG), generated at Coke Plant Schwelgern, is treated in the by-product plant and its valuable by-products are recovered by multi-stage absorbers. These processes are temperature-sensitive. The governmental permit limits the environment relevant concentration of substances like hydrogen sulphur in the purified COG and controls the limits via online monitoring. The efficiency of COG-treatment is sufficient, if the process is operated following the design parameters. The efficiency decreases during hot summer times which becomes more and more relevant. The original design of Coke Plant Schwelgern was not able to guarantee full production at hot summer times without violation of the environmental COG-limits. The necessary cooling capacity for the absorption processes at the Schwelgern coke plant is provided by cooling towers. Thus, the cooling capacity depends on the ambient conditions, the installation of additional chiller cooling capacity becomes necessary. Conventional chillers have a very high electrical energy requirement and, in addition, the coolant is harmful to the environment, alternative energy sources must be tapped. At Coke Plant Schwelgern, the by-product plant generates a steady flow of hot waste water, which is an untapped potential for chiller water generation. The so-called absorption chillers can use this heat source to generate cooling water for cooling down COG and circulating water feeds to optimize the COG-treatment during hot periods, guaranteeing full coke production without violation of environmental COG-limits. This presentation illustrates the theoretical considerations for this project, reflects about commissioning and presents first results.

Rimnac, Axel, Primetals Technologies Austria, Austria

Co-Author: Konrad Krimpelstaetter, Primetals Technologies Austria • Alfred Seyr, Primetals Technologies Austria

Abstract: "This paper presents a web-based system that describes the interaction of a hot rolling mill and the rolled material. It represents a combined digital twin simulation of the plant and the product in terms of temperature-time deformation behavior resulting from the specific rolling schedule of a customer-specific plant, be it e.g., a hot strip mill, thin-slab casting and rolling facility, Steckel- or heavy plate mill. This tool is combined with a model to describe the microstructure evolution of the processed material. The physical description of the material is based on evolution equations for the austenitic phase regarding recrystallization, grain growth, precipitation of various compounds as well as austenite decomposition including a prediction for as-rolled mechanical properties for the cold material based on the phenomenological description of well-known strengthening mechanisms and their combination for multi-phase steels. The description of the interaction between process equipment and product is considered by using derivates of in-house design models that have precise parametrizations for mechanical as well as thermal interaction with the processed material. Extensive information computed on forces, torques, temperatures, throughput, and microstructural information as well as predictions on capability constraints are available via corresponding visualization including proper export functionality for the generation of e.g., reports. In this way the user is in the position to gain detailed insight in the hot rolling process, e.g. the analysis of already produced materials or performing what-if analysis to acquire information on upcoming products in a development cycle. The computation facilities are hosted by Primetals Technologies. Customer access is established via a standard web browser and customer Know-How is fully protected by using high level state-of the art security mechanisms."

Rinaldi, Marco, Danieli Corus B.V, Italy

Co-Author: Marco Rinaldi, Danieli Corus B.V • Andrea Biliotti, Danieli Centro Combustion • Giuseppe Ambrogini, Acciaierie Bertoli Safau

Abstract: The efficient operation of a reheating furnace depends not only on mechanical, thermal, chemical and automation, but also on the synergy with the rolling mill and all these aspects combined. Danieli has recently achieved outstanding results at ABS’ QWR 4.0 plant, which have been possible thanks to the integration of new and existing technological equipment installed in a reheating furnace. Key for such improvement is the complete integration of the reheating furnace with the rolling mill, leading to the “integrated reheating furnace” concept, which enabled an integrated view not only of the furnace but also of the furnace within the plant itself. This achievement is the result of accurate furnace control, to optimize material quality (decarburization and/or austenitic grain size), emissions rules (CO and NOx), metallic yield (scale) and productivity at the same time. The furnace set-up and control were made possible using a bloom-heating thermo-mathematical model dynamically modified by both a thermo-mechanical model—based on measured and theoretical torques/temperatures at rolling mill— and emissivity, based on combustion ratio of each zone.

Rische, Marco, ABP Induction Systems GmbH, Germany

Co-Author: Josef Gahleitner, Primetals Technologies Austria GmbH • Axel Walther, ABP Induction Systems GmbH • Martin Ennen, ABP Induction Systems GmbH

Abstract: The steel industry is the second largest industrial emitter of CO2 emissions worldwide. The increasing pressure to reduce these emissions is leading to a move away from fossil fuels in the future. Alternatives are the use of green energy via the generation of DRI/HBI for pig iron production with green hydrogen. In further processing, this opens up new possibilities for alternative applications in the steel making and rolling mill processes, which offer almost CO2-free heating of the material, both in the melting process and in reheating. One of these alternative processes is induction. The energy input is achieved directly via the electromagnetic field into the material to be heated. The process is dynamic, easily controllable and, if green energy is used, almost CO2-neutral. Both in the melting process and in the area of reheating, the established processes can thus be complemented and thereby reduce the emissions of the overall process. The hybrid addition of induction heating systems not only improves the emission behavior in the overall process at manageable investment costs: Due to lower burning rates of the aggregates and an extremely good stirring effect during the melting process, the process is excellently suited for melting aggregates at the lowest possible energy consumption with good mixing of the target analysis in the melt and with higher yields as conventional processes contribute. With the dynamic behavior in the heating process due to the direct energy input into the material, the induction heating process is also a good alternative to the existing gas furnace for reheating. The induction furnace can be positioned complementarily upstream or downstream of the gas furnace. Both variants enable a reduction of the total energy consumption as well as the gas consumption and thus a directly measurable CO2 reduction in the reheating process.

Ritter, Agnes, McKinsey & Company , Austria

Co-Author: Marlene Weimer, McKinsey & Company, Inc.

Abstract: Steel industry is under pressure as climate targets aim for net-zero GHG emissions by 2045 in EU. Doing so requires increasing annual investment into new technology and assets. Demand for low-CO2—or “green”—products is ramping up as end customers, manufacturers, and governments push for increased sustainability and circularity. Primary materials processing makes up the majority of GHG emissions for many industrial products, which has led to increased attention on decarbonizing core contributing commodities and will strengthen the need for recycling materials. In turn, time-bound green premiums are emerging for certain steel applications. This paper lays out the observed and potential supply–demand balances across four core commodities: Understanding where the extra cost for green steel can be captured will influence industry transition path and needed innovation. We assessed premiums for low-CO₂ materials premiums by modelling the expected demand, supply of green steel by technology, and green premiums required. McKinsey steel team – authors and presentation tbd BZ or Agnes

Rivetti, Pierpaolo, SMS Concast AG , Switzerland

Co-Author: Stephan Feldhaus, SMS Concast AG • Shuai Niu, Nanjing Iron & Steel Co., Ltd. • Xinghua Chen, Nanjing Iron & Steel Co., Ltd. • Wei Deng, Nanjing Iron & Steel Co., Ltd. • Zhiyong Hu, Nanjing Iron & Steel Co., Ltd.

Abstract: The present study focusses on the internal quality improvement of the spring (54SiCr6) and bearing (GCr15) steel blooms by optimizing the MSR (Mechanical Soft Reduction) and MHR (Mechanical Hard Reduction) process parameters on the continuous casting machine supplied by SMS Concast AG at Nanjing Iron &Steel Co. In addition to MSR and MHR, the caster is equipped with electromechanical stoppers, mold electromagnetic stirrer (M-EMS), final electromagnetic stirrer (F-EMS) and air-mist spray cooling. State of the art L1 and L2 software complete the technological packages for this machine. Solidification status of the blooms with sections of 255 mm x 300 mm and 330 mm x 420 mm were determined by using the verified FEMS solidification model provided by SMS Concast AG. Theoretical effective reduction region was proposed based on the simulated crater end position of the blooms. Intensive industrial trials were conducted to study the effect of the reduction rate on the V-shaped and centerline segregation of the blooms. The results show that obvious improvement of internal quality of the spring and bearing steel blooms of both sections could be obtained by increasing the reduction amount and applying a suitable reduction rate in the effective reduction region during casting.

Robinet, Jean-Pierre, CLECIM SAS, France

Co-Author: Stanislas Mauuary, CLECIM SAS

Abstract: Megatrends such as Electromobility shape the industrial world, this is today a well-known direction for steel producers’ development. For decades since the 80ies, Clecim has been present in Rolling and Processing of high silicon steels, always reinventing its products to fit with the new requirements. From industrial transformers to electromobility, the tolerances of silicon steel have gone more drastic in shape, flatness, thermal treatments and rolling precision. Of course, Clecim SAS remains true to its origins of rolling mill builder with the evolution of its Power 6-Hi mill for those products: smaller rolls, powerful coilers and torque, adaptive cooling solutions and of course, the necessary work roll and intermediate roll actuation with bending and shifting allow our mills to cope with flatness and quality in thin high strength gauges - always wider. The experience at the root of the edge drop management lies in process knowledge already acquired between 2004 and 2010 and enable Clecim to propose revamps of customers 4 Hi mills adapting the necessary actuators to limit edge losses. On Processing Lines, the advanced side trimmer and scrap choppers, able of online width adjustment complete the care for smooth edges and Asolid-state welding machines able to cut and weld laser wise have been the trademark and specialty of Clecim for more than one decade. Now, the new LW21L is designed for silicon very thin gauges and can match the sharp edge of the tolerances demands for final products dedicated to car motors, especially on stack of stator & rotor. The SIAS® DeepLearning including its pinhole channel offers the full set of analysis tools to detect the smallest defect. Today, Clecim SAS is proud to present you the evolution of its machines for electromobility business in details and the results achieved.

Rotherm, Tizian , SMS group, Germany

Co-Author: Christian Dornscheidt, SMS group

Abstract: In strip processing lines, the ends of the strip have to be joined together to form an endless strip, which is necessary for a continuous process. Laser welding fulfills this task perfectly. The X-Roll® laser welder is capable of welding a wide field of steel grades, even those deemed as hard-to-weld. This is possible due to the patented inductive heat treatment system. Other technical highlights are a low cycle time, automatic welding parameter calculation, the quality assurance system, and a fast knife cassette exchange-procedure. The laser source can be either a carbon dioxide or a solid-sate laser resonator. The solid-state laser offers advantages such as less operational costs and a more flexible design. Yet the carbon dioxide laser is the more established technology on the market. As part of our processing lines, the X-Roll® laser welder utilizes synergy effects to optimize and stabilize the production. The X-Roll® laser welder is not only confined to new lines, it can also be suited for a revamp in an existing processing line. Due to the slim design of the machine, the replacement of obsolete flash butt welding machines or older laser welding machines can be done with low effort. This enhances the variety of input material. Older welding machines are often not capable of welding modern steel grades in a reliable manner, since the alloying content of the strip material effects its weldability. The paper will include information about solid state lasers, weld-seam heat treatment, revamps, preventive maintenance and possibilities of digitization. Reference implementations will be shown as well.

Roveda, Michele, Tenova S.p.A., Italy

Co-Author: Stefano Moroni, Tenova S.p.A.

Abstract: Furnace Digital Packages are Tenova’s Industry 4.0 solution to shift the furnaces from traditional equipment to more efficient and technological production units. They aim to improve: • Process and product quality • Overall efficiency • Plant availability Tenova Furnace Digital Packages comprise both AI / ML dedicated algorithms and dedicated counters, alerts and alarms. The former easily allow field data analysis and new insights to the production team, the latter give an effective help to the maintenance team by keeping monitored the wearable and critical parts. The platform services allows for packages synergy with the Tenova Dynamic Furnace which is the digital twin of the real furnace: a dedicated tool specifically designed to improve the production schedule management and for the optimization heating practices. The tool helps the process and metallurgical engineers in developing new heating strategies and get evaluation about furnace behaviour (e.g. consumption, set-points, etc.) as well as final slab/billet/bloom heating quality. The deployment of ML models and packages started in 2020, first figures from field about real benefits are already available while development of features is still ongoing.

Rozhkova, Tetiana, Centre de Pyrolyse de Marienau, France

Co-Author: Stéphanie Penerat, Centre de Pyrolyse de Marienau

Abstract: “VITAL: Vitrinite Analysis” automatic measurement system of coal vitrinite reflectance, as well as maceral analysis was developed by working group composed of ArcelorMittal Dunkerque and Fos-Sur-Mer as well as ArcelorMittal Research SA and Centre de Pyrolyse de Marienau. The working group consisted of accredited by ICCP petrographer, plant and research specialists in coals and image analysis. VITAL system can be applied to all coking and semi-soft coking coals from 0,5% to 1,7% of vitrinite reflectance (i.e. reflectance in between lignite and anthracite coalification stages), of various organic and mineral composition (rich or poor in reactive vitrinite maceral group coals). The system offers rapid and automatic vitrinite reflectance and maceral analysis measurement with no intervention of experienced petrographer.

Rudge, David, Hatch Ltd., Canada

Co-Author: Sa Ge, Hatch Ltd • Terry Koehler, Hatch Ltd • Chris Walker, Hatch Ltd

Abstract: The future of steelmaking requires changes to achieve significant reduction of greenhouse gas emissions, using new process flowsheets. One approach commonly considered is the use of direct reduced iron (DRI) with an electrical arc furnace (EAF); however, this poses significant challenges when using lower grade ores / pellets and in the future when using hydrogen-DRI. This paper describes a method to improve the process yield and efficiency, using an electric smelting furnace technology. The smelting furnace (ESF) efficiently converts DRI into pig iron (hot metal), which can be used downstream in an EAF or basic oxygen furnace (BOF), or cast / granulated for future use. The smelting furnace leverages advanced furnace technology developed over 60+ years for ironmaking and ferro-nickel applications, and has also been demonstrated for direct steelmaking. These furnaces are operated continuously with high power and large throughputs. Technologies have been developed, tested, and optimized to ensure safe and efficient operation, and a long furnace campaign life. This new approach eases the shift to green steelmaking by using existing facilities and pellet supply chains, and provides higher yields and reduced lifecycle costs.

Ruhkamp, Winfried, Loesche GmbH, Germany

Co-Author: Holger Wulfert, Loesche GmbH • Andreas Jungmann, Cala Aufbereitungstechnik GmbH & Co. KG

Abstract: The development of recycling processes for the use of material resources from industrial waste products or by-products is becoming more and more important. To this end, comminution processes play a key role in processing the material in such a way that recyclable materials become exposed for subsequent separation processes. It was therefore only a matter of time before LOESCHE GmbH, with its decades of experience in fine comminution processes, became the centre of attention for prospective customers who would like to develop and optimize recycling processes. Worldwide three digit mio. tons of steel slags are being produced yearly. The paper/presentation focuses on the development of a dry grinding process for the metal recovery from stainless steel slags. The first production plant worldwide for the dry processing of stainless steel slags with a vertical roller mill was commissioned in Charleroi/Belgium in 2012. The throughput of the plant is ~ 20 t/h. The ground slag has a fineness of approx. 3500 Blaine. The metal recovery is bigger than 90%, the metal content of the concentrate is between 85 to 95% (recoverable metal bigger than 63µm). In addition, the presentation will highlight further possibilities for slag processing and provide an outlook on future technologies that close the steel production loop and increase sustainability.

Rupp, Fabian, Danieli Corus B.V, Germany

Co-Author: Miguel Furlaneto, Danieli Corus B.V

Abstract: Whereas originally, coke plant lifetime would be determined by its technical integrity and in more recent decades by its environmental compliance, steel producers who are developing their decarbonization strategies currently face the necessity to have both these aspects match the projected termination of coke consumption at their site. Coke plant technology has been developed to such a level of maturity that lifetime extension at minimum emissions to the environment is feasible under any scenario. However, with the potentially limited lifetime requirement dictated by the selected decarbonization scenario, applying modern technology may easily stretch the plant’s lifetime beyond requirement while requiring excess capex allocation. A coke plant comprises a large multitude of refractory constructions as well as mechanical equipment, all of which are connected to the plant’s lifetime capability, process performance and environmental performance. Based on comprehensive knowledge of coke plant technology as well as decades of experience in the design, construction and maintenance of coke plants, Giprokoks and Danieli Corus have developed condition assessment and lifetime extension strategies that allow for extending a plant’s lifetime to match plant lifecycle requirements while minimizing direct cost and production loss. These strategies may include minor or major repairs of and modifications to refractories as well as repairs of and modernization of mechanical equipment such as doors, valves, hoods and mains/ducting. In any scenario, a program for minimizing emissions to the environment and to comply with regulations will be advised.

Rusu, Ion, BM GROUP POLYTEC S.p.A., Italy

Co-Author: Ion Rusu, BM GROUP POLYTEC S.p.A.

Abstract: The paper depicts a robotic cell, which has been ad-hoc developed in order to be installed in the steel shop and support the operators during inspection, cleaning and replacement of the refractory components of the ladle sliding gate. This device is allowing opening the bottom of the ladle so that the liquid steel can run into the tundish of the continuous caster. The developed robotic cell represent an innovative attempt to create a cooperative environment where the technicians and a robot interact in a safe and ergonomic way. This system, which is installed and tested in an Italian integrated steelworks, allows improving both the health and safety condition of the workers and the quality and repeatability of the operations. It automatically manages the sliding gate maintenance, in order to increase safety and operational accuracy, stability in the repetitively and to optimize process times control. This multi-tool robotic cell is equipped with: Extraction/Insertion tool Refractory nozzle extraction tool Tool to remove fixed plate Nozzle cleaning tool