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Society, Materials, and the Environment: the Case of Steel
metals Review Society, Materials, and the Environment: The Case of Steel Jean-Pierre Birat IF Steelman, Moselle, 57280 Semécourt, France; [email protected]; Tel.: +333-8751-1117 Received: 1 February 2020; Accepted: 25 February 2020; Published: 2 March 2020 Abstract: This paper reviews the relationship between the production of steel and the environment as it stands today. It deals with raw material issues (availability, scarcity), energy resources, and generation of by-products, i.e., the circular economy, the anthropogenic iron mine, and the energy transition. The paper also deals with emissions to air (dust, Particulate Matter, heavy metals, Persistant Organics Pollutants), water, and soil, i.e., with toxicity, ecotoxicity, epidemiology, and health issues, but also greenhouse gas emissions, i.e., climate change. The loss of biodiversity is also mentioned. All these topics are analyzed with historical hindsight and the present understanding of their physics and chemistry is discussed, stressing areas where knowledge is still lacking. In the face of all these issues, technological solutions were sought to alleviate their effects: many areas are presently satisfactorily handled (the circular economy—a historical’ practice in the case of steel, energy conservation, air/water/soil emissions) and in line with present environmental regulations; on the other hand, there are important hanging issues, such as the generation of mine tailings (and tailings dam failures), the emissions of greenhouse gases (the steel industry plans to become carbon-neutral by 2050, at least in the EU), and the emission of fine PM, which WHO correlates with premature deaths. Moreover, present regulatory levels of emissions will necessarily become much stricter. -
On a Mathematical Model for Case Hardening of Steel
On a mathematical model for case hardening of steel vorgelegt von Dott.ssa Lucia Panizzi Von der Fakultät II ‚ Mathematik und Naturwissenschaften der Technischen Universität Berlin zur Erlangung des akademischen Grades Doktor der Naturwissenschaften Dr. rer. nat. sowie der Classe di Scienze der Scuola Normale Superiore di Pisa als Diploma di Perfezionamento in Matematica per la Tecnologia e l’Industria genehmigte Dissertation Promotionsausschuss: Berichter/Gutachter: Prof. A. Fasano (Univerisità di Firenze) Berichter/Gutachter: Prof. D. Hömberg (Technische Universität Berlin) Gutachter: Prof. L. Formaggia (Politecnico di Milano) Gutachter: Prof. M. Primicerio (Università di Firenze) Gutachter: Prof. F. Tröltzsch (Technische Universität Berlin) Gutachter: Prof. P. Wittbold (Technische Universität Berlin) Tag der wissenschaftlichen Aussprache: 05.03.2010 Berlin 2010 D83 i Eidesstattliche Versicherung Hiermit erkläre ich, dass die vorliegende Dissertation: On a mathematical model for case hardening of steel selbständig verfasst wurde. Die benutzten Hilfsmittel und Quellen wurden von mir angegeben, weitere wurden nicht verwendet. ii Erklärung Hiermit erkläre ich, dass die Anmeldung meiner Promotionsabsicht früher nicht bei einer anderen Hochschule oder einer anderen Fakultät beantragt wurde. Teile meiner Dissertation sind darüber hinaus schon veröffentlich worden, welche im Folgenden aufgelistet sind: • D. Hömberg, A. Fasano, L. Panizzi A mathematical model for case hardening of steel. angenommen zur Veröffentlichung in "Mathematical Models and Methods in Applied Sciences" (M3AS), 2009. • P. Krejčí, L. Panizzi. Regularity and uniqueness in quasilinear parabolic systems. angenommen zur Veröffentlichung in "Applications of Mathematics", 2009. iii Compendio Nonostante la disponibilità di numerosi nuovi materiali, l’acciaio rimane il ma- teriale di base della moderna società industriale. L’uso dell’ acciaio con peculiari caratteristiche (durezza, resistenza all’uso, malleabilità etc.) è perciò assai diffuso in molti settori della tecnica. -
UNDERSTANDING and MEASURING DECARBURIZATION Understanding the Forces Behind Decarburization Is the First Step Toward Minimizing Its Detrimental Effects
22 UNDERSTANDING AND MEASURING DECARBURIZATION Understanding the forces behind decarburization is the first step toward minimizing its detrimental effects. George F. Vander Voort, FASM*, Struers Inc. (Consultant), Cleveland ecarburization is detrimental to crostructure of carbon contents close to the maximum depth of decarburization the wear life and fatigue life of the core may be difficult to discern. The is established. Because the carbon dif- steel heat-treated components. MAD determined by hardness traverse fusion rate increases with temperature ADVANCED MATERIALS & PROCESSES | FEBRUARY 2015 2015 FEBRUARY | & PROCESSES MATERIALS ADVANCED D This article explores some factors that may be slightly shallower than that de- when the structure is fully austenitic, cause decarburization while concentrat- termined by quantitative carbon analysis MAD also increases as temperature rises ing on its measurement. In most produc- with the electron microprobe. This is es- above the Ac3. For temperatures in the tion tests, light microscopes are used to pecially true when the bulk carbon con- two-phase region, between the Ac1 and scan the surface of a polished and etched tent exceeds about 0.45 wt%, as the rela- Ac3, the process is more complex. Carbon cross-section to find what appears to be tionship between carbon in the austenite diffusion rates in ferrite and austenite the greatest depth of total carbon loss before quenching to form martensite and are different, and are influenced by both (free-ferrite depth, or FFD) and the great- the as-quenched hardness loses its linear temperature and composition. est depth of combined FFD and partial nature above this carbon level. Decarburization is a serious prob- loss of carbon to determine the maxi- lem because surface properties are infe- mum affected depth (MAD). -
Master's Thesis
MASTER'S THESIS Energy System Analysis in the Swedish Iron and Steel Industry Ernesto Ubieto Master of Science (120 credits) Mechanical Engineering Luleå University of Technology Department of Engineering Sciences and Mathematics Energy System Analysis of the Swedish Iron and Steel Industry Ernesto Ubieto Udina Table of contents 1 INTRODUCTION ................................................................................................................. 7 2 OBJECTIVES ....................................................................................................................... 8 3 METHODOLOGY ................................................................................................................ 9 3.1 Methodology of System Analysis ............................................................................... 9 3.1.1 Scope of the Analysis ....................................................................................... 10 3.1.2 Boundaries of the Analysis ............................................................................... 11 3.1.3 Time frames ..................................................................................................... 11 3.1.4 Components of the System .............................................................................. 12 3.1.5 Connections within the system ........................................................................ 13 3.1.6 Limitations of the study ................................................................................... 15 3.1.7 Tracking CO2 -
The Preparation of High-Purity Iron (99.987%) Employing a Process of Direct Reduction–Melting Separation–Slag Refining
materials Article The Preparation of High-Purity Iron (99.987%) Employing a Process of Direct Reduction–Melting Separation–Slag Refining Bin Li 1,2, Guanyong Sun 1,2, Shaoying Li 1,2, Hanjie Guo 1,2,* and Jing Guo 1,2 1 School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing 100083, China; [email protected] (B.L.); [email protected] (G.S.); [email protected] (S.L.); [email protected] (J.G.) 2 Beijing Key Laboratory of Special Melting and Preparation of High-End Metal Materials, Beijing 100083, China * Correspondence: [email protected]; Tel.: +86-138-0136-9943 Received: 9 March 2020; Accepted: 9 April 2020; Published: 14 April 2020 Abstract: In this study, high-purity iron with purity of 99.987 wt.% was prepared employing a process of direct reduction–melting separation–slag refining. The iron ore after pelletizing and roasting was reduced by hydrogen to obtain direct reduced iron (DRI). Carbon and sulfur were removed in this step and other impurities such as silicon, manganese, titanium and aluminum were excluded from metallic iron. Dephosphorization was implemented simultaneously during the melting separation step by making use of the ferrous oxide (FeO) contained in DRI. The problem of deoxidization for pure iron was solved, and the oxygen content of pure iron was reduced to 10 ppm by refining with a high basicity slag. Compared with electrolytic iron, the pure iron prepared by this method has tremendous advantages in cost and scale and has more outstanding quality than technically pure iron, making it possible to produce high-purity iron in a short-flow, large-scale, low-cost and environmentally friendly way. -
An Introduction to Nitriding
01_Nitriding.qxd 9/30/03 9:58 AM Page 1 © 2003 ASM International. All Rights Reserved. www.asminternational.org Practical Nitriding and Ferritic Nitrocarburizing (#06950G) CHAPTER 1 An Introduction to Nitriding THE NITRIDING PROCESS, first developed in the early 1900s, con- tinues to play an important role in many industrial applications. Along with the derivative nitrocarburizing process, nitriding often is used in the manufacture of aircraft, bearings, automotive components, textile machin- ery, and turbine generation systems. Though wrapped in a bit of “alchemi- cal mystery,” it remains the simplest of the case hardening techniques. The secret of the nitriding process is that it does not require a phase change from ferrite to austenite, nor does it require a further change from austenite to martensite. In other words, the steel remains in the ferrite phase (or cementite, depending on alloy composition) during the complete proce- dure. This means that the molecular structure of the ferrite (body-centered cubic, or bcc, lattice) does not change its configuration or grow into the face-centered cubic (fcc) lattice characteristic of austenite, as occurs in more conventional methods such as carburizing. Furthermore, because only free cooling takes place, rather than rapid cooling or quenching, no subsequent transformation from austenite to martensite occurs. Again, there is no molecular size change and, more importantly, no dimensional change, only slight growth due to the volumetric change of the steel sur- face caused by the nitrogen diffusion. What can (and does) produce distor- tion are the induced surface stresses being released by the heat of the process, causing movement in the form of twisting and bending. -
20. Iron and Steel Part II Copy
USES FOR TYPES OF STEELS • Low carbon steel (0.08 - 0.35 % carbon) is ductile with low brittleness. It is is used for ANCIENT IRON auto body parts, home appliances, tin cans, I beams for construction. AND STEEL • Medium carbon steel (0.35 - 0.5 % carbon) (Part II) is used as crankshaft, gears, railroad axels. (Part II) They are difficult to weld. • High carbon steel (> 0.5 % carbon) is used for railroad wheels and rails, wrenches, steel cable, tools, dies, piano wire etc. BLAST FURNACE CAST IRON (PIG IRON) • Contains 1.5 - 5 % carbon. • Its melting point is 1130 oC. • The metal will shatter with a hard blow. • Carbon in the form of graphite exists as flakes • Graphite serves as a lubricant (excellent bearing material). 1 Cast Grey Iron Blast furnace at Cast Grey Iron Karabük Iron works Cast Gray Iron Graphite flakes THE FINERY CAST IRON OBJECTS THE FINERY Cast cannon 15th. Cent. 2 INDIRECT METHOD OF STEEL BESSEMER PROCESS PRODUCTION (THE BESSEMER PROCESS) Crude cast iron from the blast furnace is remelted in a hearth (the finary) and subjected to a forced draught of air. The excess carbon is oxidized to carbon dioxide. The refined pig iron which is called malleable iron is now ready for final forging. BESSEMER PROCESS FORMS OF IRON CAST IRON Decarburization From Blast Furnace M.P. 1130oC 1,5-4.5 % C Bessemer STEEL Process M.P. 1400o C 0.1-0.9 % C WROUGHT IRON From Bloomery Cementation M.P 1535o C 0.06 % C Carburization 3 DIFFERENCES BETWEEN BLOOMERY ALLOY STEELS AND BLAST FURNACE • Increase in temperature (1300 - 1400oC) • Alloy steel describes steel that contain one or more alloying elements in addition to carbon. -
The Future of Steelmaking– Howeuropean the MANAGEMENT SUMMARY
05.2020 The future of steelmaking – How the European steel industry can achieve carbon neutrality MANAGEMENT SUMMARY The future of steelmaking / How the European steel industry can achieve carbon neutrality The European steelmaking industry emits 4% of the EU's total CO2 emissions. It is under growing public, economic and regulatory pressure to become carbon neutral by 2050, in line with EU targets. About 60% of European steel is produced via the so-called primary route, an efficient but highly carbon-intensive production method. The industry already uses carbon mitigation techniques, but these are insufficient to significantly reduce or eliminate carbon emissions. The development and implementation of new technologies is underway. With limited investment cycles left until the 2050 deadline, the European steelmaking industry must decide on which new technology to invest in within the next 5-10 years. We assess the most promising emerging technologies in this report. They fall into two main categories: carbon capture, use and/or storage (CCUS), and alternative reduction of iron ore. CCUS processes can be readily integrated into existing steel plants, but cannot alone achieve carbon neutrality. If biomass is used in place of fossil fuels in the steelmaking process, CCUS can result in a negative carbon balance. Alternative reduction technologies include hydrogen-based direct reduction processes and electrolytic reduction methods. Most are not well developed and require huge amounts of green energy, but they hold the promise of carbon-neutral steelmaking. One alternative reduction process, H2-based shaft furnace direct reduction, offers particular promise due to its emissions-reduction potential and state of readiness. -
AISI | Electric Arc Furnace Steelmaking
http://www.steel.org/AM/Template.cfm?Section=Articles3&TEMPLATE=/CM/HTMLDisplay.cfm&CONTENTID=12308 Home Steelworks Home Electric Arc Furnace Steelmaking By Jeremy A. T. Jones, Nupro Corporation SIGN UP to receive AISI's FREE e-news! Read the latest. Email: Name: Join Courtesy of Mannesmann Demag Corp. FURNACE OPERATIONS The electric arc furnace operates as a batch melting process producing batches of molten steel known "heats". The electric arc furnace operating cycle is called the tap-to-tap cycle and is made up of the following operations: Furnace charging Melting Refining De-slagging Tapping Furnace turn-around Modern operations aim for a tap-to-tap time of less than 60 minutes. Some twin shell furnace operations are achieving tap-to-tap times of 35 to 40 minutes. 10/3/2008 9:36 AM http://www.steel.org/AM/Template.cfm?Section=Articles3&TEMPLATE=/CM/HTMLDisplay.cfm&CONTENTID=12308 Furnace Charging The first step in the production of any heat is to select the grade of steel to be made. Usually a schedule is developed prior to each production shift. Thus the melter will know in advance the schedule for his shift. The scrap yard operator will prepare buckets of scrap according to the needs of the melter. Preparation of the charge bucket is an important operation, not only to ensure proper melt-in chemistry but also to ensure good melting conditions. The scrap must be layered in the bucket according to size and density to promote the rapid formation of a liquid pool of steel in the hearth while providing protection for the sidewalls and roof from electric arc radiation. -
Investigation of Reduction of Magnetite Based Carbon Composite Pellets Under Semi-Fusion Conditions
Physicochem. Probl. Miner. Process., 54(3), 2018, 621-628 Physicochemical Problems of Mineral Processing ISSN 1643-1049 http://www.journalssystem.com/ppmp/ © Wroclaw University of Science and Technology Received March 16, 2017; reviewed; accepted October 6, 2017 Investigation of reduction of magnetite based carbon composite pellets under semi-fusion conditions Yunus Emre Benkli 1, Mustafa Boyrazli 2, Guzide Meltem Lule Senoz 1, Zeki Cizmecioglu 3 1Ataturk University, Faculty of Engineering, Department of Metallurgical and Materials Engineering, 25240, Erzurum, Turkey 2 Firat University, Faculty of Engineering, Department of Metallurgical and Materials Engineering, 23119, Elazıg, Turkey 3 Istanbul Commerce University, Faculty of Engineering and Design, Department of Jewelry Engineering, 34210, Istanbul, Turkey Corresponding author: [email protected] (Yunus Emre Benkli) Abstract: In this study, carbon composite pellets were exposed to a reduction test under low temperature and semi-fusion conditions in which iron was melted without a solid form of slag deteriorated. The purpose of the reduction experiments under the semi-fusion condition was to produce an iron nugget which had physical and chemical properties similar to blast furnace pig iron at lower temperatures. These nuggets were produced from pellets that were made from a mixture of iron oxide, coke, flux, and a binder. These nuggets heated in a furnace with a chamber temperature of 1330 C. The produced dried carbon composite pellets were melted and carbureted in a single-stage process. In this study, three distinct products were produced as a function of furnace residence time at fixed furnace temperature (1330 C). These products were direct reduced iron (DRI), transition direct reduced iron (TDRI), and iron nuggets produced at residence times 8-24, 32-40 min, and 48 min, respectively. -
CO2 Emission Reduction Potential in the Steel Industry by Integration of a Direct Reduction Process Into Existing Steel Mills Ab
Challenges for Petrochemicals and Fuels: Integration of Value Chains and Energy Transition DGMK Conference October 10 – 12, 2018 in Berlin, Germany CO2 Emission Reduction Potential in the Steel Industry by Integration of a Direct Reduction Process into Existing Steel Mills N. Müller, G. Herz, E. Reichelt, M. Jahn Fraunhofer IKTS, Dresden, Germany Abstract In the context of climate change, the reduction of greenhouse gas emissions in all economic sectors is considered to be an important factor in order to meet the demands of a sustainable energy system. The steel industry as one of the large industrial CO2 emitters is currently highly dependent on fossil resources. In order to reduce coke consumption and thereby CO2 emissions while still being able to further utilize existing blast furnaces, the possibility of in- cluding a direct reduction process (DRP) into a fully integrated steel mill was investigated. Therefore, a blast furnace model, derived from literature data and implemented in Aspen Plus, was used to analyze the impact of DRI in the blast furnace process. Furthermore, a state-of-the-art DRP was modeled to investigate the possibility of substituting the reducing agent natural gas with hydrogen. A sensitivity analysis was carried out in order to find the boundary percentage of hydrogen as a reducing agent without penalty to the DRI quality. Lastly, the two modeled process steps were combined to form a route of producing hot met- al. By varying boundary conditions of the DRP while recording the CO2 emissions of the two process steps, the overall potential for the reduction of CO2 emissions was estimated. -
Zero-Carbon Steel Making
Zero-carbon steel making: The opportunities and role of Australia in nurturing a `green steel' industry Mahesh Venkataraman [email protected] Zsuzsanna Csereklyei [email protected] Emma Aisbett [email protected] Alireza Rahbari [email protected] Frank Jotzo [email protected] Michael Lord [email protected] John Pye [email protected] Further information: http://energy.anu.edu.au December 19, 2019 Contents 1 Introduction 2 5 Australia's role in the zero-carbon steelmaking transition 11 2 Current iron and steel making tech- 5.1 Australian initiatives for reducing nologies 3 emissions in the steel industry . 12 3 Technologies for reducing the carbon 5.2 Potential for a green steel industry footprint of the steel industry 6 in Australia . 14 3.1 Hydrogen-based steelmaking . .7 6 Outlook 17 3.2 Electrolytic production of iron . .7 References 20 4 Is zero-carbon steelmaking really necessary? 9 1. Introduction Steel is arguably the most important structural material used in society, especially in those countries undergoing rapid development. There is a strong correlation between a country's economic devel- opment and its cumulative metal consumption. Zheng et al. [1], for example, find that a country's `metal footprint' (in tonnes per capita) tends to increase by 1.9% for every 1% increase in gross domestic product (GDP) per capita. The global production of crude steel has increased steadily on an average by 1.8% in the last five years. In 2018, it reached an astounding 1,808 million tonnes [2], with most of the growth in demand occurring in developing countries such as India and China [1, 3].