The eaf is different from the blast furnace as it produces steel by using an electrical current to melt scrap steel andor direct reduced iron. Recycling of electric arc furnace eaf dust for use in steel. Recycling of electric arc furnace eaf dust for use in. This technology results in the production of metal dusts, slag, and gaseous products. Bos basic oxygen furnace and the more modern eaf electric arc furnace methods. The cost is for a notional producer a typical size plant of about 1m tyear capacity, based in japan, using a 100% scrap charge to eaf no dri or irons, and producing commodity grade carbon steel for long products with average labour productivity. Steelmaking has played a crucial role in the development of ancient, medieval, and modern technological societies. Jun 21, 2016 these methods become popular for steel making into a heavy industry. Early processes of steel making were made during the classical era in ancient iran, ancient china, india, and rome but the process of ancient steelmaking was lost in the west after the fall of the western roman empire in the 5th century ce. This entire process of eaf steel making is associated with various safety hazards and risk of injury. Electric arc furnace eaf steel making technology is more than hundred years old. Eaf, electric arc furnace, modelling, process automation, steel making, melting, dri, simulation introduction most current electric arc furnace eaf steelmaking makes use of level2 automation systems nil00, hei97.
Steelmaking process an overview sciencedirect topics. The predicted total costing shown is not meant to represent an actual cost for any. Clu process clu process is similar to the aod argon oxygen decarburization process for making stainless steels. Furnace charging melting refining deslagging tapping furnace turnaround this technical document will focus primary on furnace. Steel production american iron and steel institute. The bottom cylindrical part of the profile is called a. Definitions of the process technologies considered herein can be.
Electric arc furnace eaf is a default phase in the process of making steel. Jones, nupro corporation courtesy of mannesmann demag corp. These hazards and risk arise due to extremely high temperature in eaf area. Steelmaking is the process of producing steel from iron ore andor scrap. The eaf operating cycle is called the tap to tap cycle and is made up of the following operations.
Recycled steel scrap provides the raw material for the electric arc furnaces eaf. May 05, 2016 eaf is a default phase in the process of making steel. Dmitri kopeliovich electric arc furnace eaf is a steel making furnace, in which steel scrap is heated and melted by heat of electric arcs striking between the furnace electrodes and the metal bath. Electric arc furnace steelmaking costs 2020 conversion costs for electric arc steelmaking. For many years production was limited to specialty steels supplying niche applications for industry in the united states and. The eaf dust is generated during melting of scrap in electric arc furnace and collected by bag filters or electrostatic precipitators. The eaf operating cycle charging, melting and refining 1. Co steel raritan inland lukens ameri steel caparo steel figure 2. Euroslag, which is an international organization dealing with iron and steel slag matters, has estimated that about 25. The first blast furnaces appeared in the 14th century and produced one ton per day.
Directly reduced iron directly reduced iron is a product of iron steel direct reduction from ores in the solid. The major development of the clu process was the idea to use superheated steam as the diluting gas instead of argon ar gas which is used in the aod process. Basic oxygen steelmaking bos, bop, bof, or osm, also known as linzdonawitzsteelmaking or the oxygen converter process is a method of primary steelmaking in which carbonrich molten pig iron is made into steel. For coke facilities, the battery stack is the highest source with over 95 percent of the ghg emissions for recovery by. Scrap is by far the most important resource, accounting for about 80% of all electric arc furnace metal feedstock. Pdf methods of steel manufacturing the electric arc furnace. Eaf is a default phase in the process of making steel. This process is used extensively for making highly alloyed steel such as stainless, heatresisting and highspeed steels. The steel product for which the cost is shown above is a metric tonne of eaf liquid steel. The eaf method, however, feeds recycled steel scrap through highpower electric arcs with temperatures of up to 1,650 degrees celsius to melt the metal and convert it into highquality steel. The bos method adds recycled scrap steel to the molten iron in a converter. A process model for eaf steelmaking semantic scholar.
Many countries that cannot make iron by the traditional blast furnace route but have sufficient supplies of scrap have developing steel industries based on the eaf process. About onequarter of the worlds steel is produced by the electricarc method, which uses highcurrent electric arcs to melt steel scrap and convert it into liquid steel of a specified chemical composition and temperature. Depending on the plant, 2030% of scrap is added to this process, primarily to regulate the temperature. Steel making steel making process gerdau ameristeel utilizes the electric arc furnace continuous casting method in the production of structural steel products. The electric steelmaking through the electric arc furnace eaf is the second most important steel production route in the world and the main process route for steel scrap recycling. Jan 14, 2020 the eaf method, however, feeds recycled steel scrap through highpower electric arcs with temperatures of up to 1,650 degrees celsius to melt the metal and convert it into highquality steel. In the semiintegrated process, the main ones are the slag of electric steelmaking, eaf dust and mill scale continuous casting and rolling.
Many countries are on the verge of adapting eaf that. Environmental protection agency research triangle park, north carolina 27711 september 2012. Even though equipment is improved and higher production rates can be achieved, the processes. The electrical energy used in the eaf process is only about 55% of the total energy input however this will depend on the. The eaf operates as a batch melting process producing batches of molten steel known as heats. The production of steel in an eaf is a batch process. The global output of steel from eaf furnaces is increasing. Scrap steel is charged to begin a cycle, and alloying agents and slag materials are added for refining. Costeel raritan inland lukens ameristeel caparo steel figure 2. The blast furnace is the first step in producing steel from iron oxides. At high temperatures, oxygen is blown through the metal, which reduces the carbon content to between 01. Steel making technology eaf eaf is widely used in usa. Cycles, or heats, range from about 112 to 5 hours to produce carbon steel and from 5 to 10 hours or more to produce alloy steel. Electrical energy can be supplemented with oxygen injected into the eaf.
The electric arc furnace the electric arc furnace, or eaf, is an even more modern method of steel production. A new process, which is known as conarc has been developed by sms demag. Pdf recycling of electric arc furnace eaf dust for use. Mar 19, 2015 clu refers to the creusotloire uddeholm process.
Available and emerging technologies for reducing greenhouse gas emissions from the iron and steel industry prepared by the sector policies and programs division office of air quality planning and standards u. External arc heating permits better thermal control than does the basic oxygen process, in which heating is accomplished by the. During the melting process, other metals ferroalloys are added to the steel to give it the required chemical composition. Compared to the bos process, the eaf requires less chemical reaction for refining. Methods of steel manufacturing the electric arc furnace. Once scrap is collected and delivered into the steel making plant, then this scrap is charged into electric arc furnace, then this roof with electrode covers electric arc furnace. Secondary steel making processes linkedin slideshare. Blowing oxygen through molten pig iron lowers the carbon content of the alloy and changes it into lowcarbon steel. While the common inputs for bof steelmaking are iron ore and coal, the eaf furnace operates using scrap steel steel already produced and ready to be recycled. Electric arc furnace steel making free download as powerpoint presentation. Understanding electric arc furnace steel making operations. Electric arc furnace furnaces producing in excess of 200 tons per hour. Adrev publishing, aresa, and 11 music rights societies.
The production routes considered herein focus primarily on various ais eaf options and compare them to the conventional bfbof operations. Development of the technology of electric arc furnace. Steel cost modelling notes the steel costing model the economic model shown above is prepared only to shown how liquid steel cost can be calculated through a simple cost benchmarking type approach. Eaf history, process and thermodynamics of eaf steel making. Many countries which cannot make iron by the traditional route, i. The electric arc furnace eaf process is the main process for recycling of ferrous scrap 1 and the second most important steelmaking process route in terms of global steel production 2. The use of the electric arc furnace for producing steel began early in the 20th century. The instrumentation of the furnaces allows for a quantitative time dependent measurement of the energy and mass inputs.
Recycling of electric arc furnace eaf dust for use in steel making process. These process hazards and control measures are enumerated in this guideline to make a safe working environment. Additives are used to adjust the steel to the desired chemical composition. Two kinds of electric current may be used in electric arc furnaces. Eaf steelmaking is no longer limited to specialty steels and has largely replaced other fomls. During the melting process of the steel in this type of furnace, eaf slag known also as black slag is generated after the addition of certain admixtures limestone, slag correction agents such as bauxites, and slag formers in the molten bath of the steel, in amounts between 120 and 180 kgtonne of manufactured steel.
In steelmaking, impurities such as nitrogen, silicon, phosphorus, sulfur and excess carbon most important impurity are removed from the sourced iron, and alloying elements such as manganese, nickel, chromium, carbon and vanadium are added to produce different grades of steel. Pdf recycling of electric arc furnace eaf dust for use in. In the electric arc furnace route eaf 100% scrap used. The electricity needed for this process is enough to power a town with a population of 100,000. Bof, eaf, steelmaking, liquid steel, slag, offgas, scrap, mass balance, energy balance. The electric arc furnace operating cycle is called the taptotap cycle and is made up of the following. Innovative technologies for steel and other materials 83 eaf steel production now represents over 30% of the worlds steel production and is expected to keep rising as a proportion of the worlds steel for some time 3.
This results in a high degree of purification and high quality steel can be made, so long as gas absorption due to excessively high temperatures is avoided. A steelmaking facility that are making products with low residual levels will be. Over years eaf has evolved dynamically and adopted efficient, competitive and sustainable methods in the process and the global output of steel from eaf is increasing. Downstream process stages, such as casting, reheating and rolling, are similar to those found in the bfbof route.
Mar 07, 2016 here is a description of the bof process msu. Now, this shows schematic operation of eaf process. The electric arc furnace uses primarily electrical energy to supply heat to melt scrap steel, sponge iron, or mixtures of scrap and other iron units. Tata steel has over the years, undertaken extensive research in making the process of steel making more energy efficient, economically viable and. These are basic oxygen steel making and electric arc furnace eaf steel making. Since scrap metal is used instead of molten iron, no coke making or iron making operations are associated with steel production using an eaf. The eaf operating cycle is called the tap to tap cycle and is made up of the following. Steel is primarily produced using one of two methods. Pig iron is divided into steel making pig iron, which is intended for further processing to steel by various refining processes, and foundry pig iron, from which cast iron is produced by remelting.
An electric arc furnace eaf is a furnace that heats charged material by means of an electric arc. Furnace operations the electric arc furnace operates as a batch melting process producing batches of molten steel known heats. External arc heating permits better thermal control than does the basic oxygen process, in which heating is accomplished. Specifically, this paper provides an evaluation of co2 emissions and energy consumption in steel production, from the receipt of basic raw materials to the tapping of a ladle of liquid steel. Direct reduction scrap ladle refining electric arc furnace steelmaking iron ore pellets electric arc furnace steelmaking continuous casting design by cover photo. An electric arc furnace eaf is a furnace that heats charged material by means of an electric arc industrial arc furnaces range in size from small units of approximately one ton capacity used in foundries for producing cast iron products up to about 400 ton units used for secondary steelmaking. Eaf steel production now represents over 30% of the worlds steel production. Eaf process 27092010 materials engineering neduet karachi 12. The sequence of making steel in an electric arc furnace. Dri is an alternate iron ore bearing material, which is used when the scrap is not. Once liquid steel is made from this electric arc furnace process, then liquid steel is tapped into teaming ladle. Industrial arc furnaces range in size from small units of approximately one ton capacity used in foundries for producing cast iron products up to about 400.
This is the remelting of steel without the use of primary raw materials. The capital cost is lower as compared to bof also known as ld. Dri is an alternate iron ore bearing material, which is used when the scrap is not available. It also uses liquid steel from an electric arc furnace eaf or any other similar primary steel making furnace. Secondary steelmaking involves treating the molten steel produced from both bos and eaf routes to adjust the steel composition. The electric arc furnace eaf process is the main process for recycling of ferrous scrap 1 and the second most important steelmaking process route in terms of. In the present day, we have two popular methods used for making steel in commercial processes. Profile of a blast furnace and its dimensions are adapted to technology of process, see figure. The use of eafs has expanded and now accounts for nearly 23 of steel production in the united states. Reduction process direct reduced iron drihot briquetted iron hbieaf routes to the new innovative alternative iron sources aisssteelmaking routes such as the fastmet process, the itmk3 process, fasteel, fastox, corex and hismelt. Electric arc furnace steel making steelmaking steel. Pig iron is divided into steelmaking pig iron, which is intended for further processing to. The iron from the blast furnace is then further refined and converted to steel in the basic oxygen furnace bof. Developments in electric arc furnace steelmaking dr geoffrey brooks department 0 materials science engineering.
Adrev for a 3rd party, adrev for rights holder on behalf of west one music west one us west one music group. With basic oxygen steel making process liquid pigiron and scrap steel are collected. The eaf uses scrap steel and electricity to produce molten steel. The basic oxygen steelmaking process differs from the eaf in that it is autogenous, or self. Innovative uses of hydrogen in steelmaking presentation by jayson ripke, midrex technologies, inc.
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