Air pollution control equipment for the shop was installed to meet or exceed the legal requirements of applicable air pollution ordinances and regulations. An electric arc furnace eaf is a furnacethat heats charged material by means of anelectric arc. Short history of electric steelmaking until today the electric arc furnace applied in steelmaking was invented in 1889 by paul he. Water leaks into a hot furnace in large enough quantities to become superheated and trigger a violent steam explosion. An electric arc furnace used for steelmaking consists of a refractorylined. Direct reduction scrap ladle refining electric arc furnace steelmaking iron ore pellets electric arc furnace steelmaking continuous casting design by cover photo. Solid material were firstly melted through direct arc melting, refined through the addition of the appropriate fluxes and tapped for further processing. Overview eaf automation packages energy supply and power control for a safe and stable plant operation furnace switchgear switchyard and compensation systems for meltshop and mill, nucor. The electric arc furnace uses primarily electrical energy to supply heat to melt scrap steel, sponge. Electric arc furnace eaf steelmaking technology became 100 hundred years old in the year 2000.
Carbon monoxide explosion hazards in electric arc furnace steelmaking operations. These improvements to the processing of scrap steel comprised of larger more efficient and higher capacity furnaces. Nov 09, 2016 electric arc furnace steelmaking process. Electric arc furnace design operation and working principle.
Modern electric furnace steelmaking a practical training. The lower part of the submerged electric arc furnace is composed of a cylindrical steel shell with a flat bottom or hearth. Bos basic oxygen furnace and the more modern eaf electric arc furnace methods. The furnace is equipped with one set of electrodes which are connected to a transformer and can be slewed alternatively to each of the two shells. Based on decades of experience in designing electric arc furnaces, primetals offers steel producers a broad range of powerful options for highperformance electric steelmaking. Under normal circumstances, however, the electric arc furnace charge should be 100 % scrap.
Carbon monoxide explosion hazards in electric arc furnace. Looking into an electric arc furnace with the power on. An electric arc furnace used for steelmaking consists of a refractorylined vessel, usually watercooled in. This includes eafs of all sizes and types, twinshell furnaces, and shaft furnaces in addition to all related processes, automation, and environmental systems. Ironmaking and steelmaking electric arc furnaces fastarc is the trademark for a stateoftheart electric steelmaking process technology that optimizes melt shop practices according to the available types of ferrous charge materials. Blowing oxygen in molten steel releases heat, because the reaction of oxygen with carbon. Emerging new technology started in the beginning of the twentieth century when wideranging generation of relatively cheap. Electric steelmaking the future of steel primetals. The situation is not the same in the emerging countries, where scrap is not always available in the required amount. Electric arc furnace steelmaking costs 2020 conversion costs for electric arc steelmaking. Makeup heat must be added, which uses additional energy. The chemical compositions of the input hot metal, the liquid steel produced at the end of oxygen blowing, and the molten slag, based on experimental measurements in the egyptian iron and. High pouring temperature will increase the propensity to hot tearing, increase.
Use of hot riquetted iron hi in the electric arc furnace eaf for steelmaking steel production in the eaf continues to grow both in north america and worldwide. This course covers safety, the basics of electrical and mechanical features of electric arc furnaces, refractories, and the role of raw materials. The arc temperature is above 4000c and is used to heat the bath by radiative heat transfer. Salzgitter the process shown above is illustrative only and is not designed to show the steelmaking process in detail. Development of the technology of electric arc furnace.
Development of the technology of electric arc furnace steelmaking. The electric steel process is characterized by its flexibility and, in the case of smaller steelmaking units socalled minimills with 300 to 1,200kta its cost effectiveness. In addition, the hot offgases often require external cooling prior to fume removal. The program will explore the fundamentals of electric furnace steelmaking technology, the use of energy inputs, the steelmaking process, electrodes and environmental concerns for electric steelmaking. Overview eaf automation packages energy supply and power control. Ultrahigh power electric arc furnace,melting furnacexi. For example, in 2004 world wide steelmaking production via electric arc furnace was 31,9% from total crude steel production. In the electric arc furnace, steel is produced only through scrap fusion. Main melting period these furnaces use a tremendous quantity of power. 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. May 05, 2016 fig 1 the first heroult electric arc furnace. An electric arc furnace eaf is a furnace that heats charged material by means of an electric arc. Eafs are often used in steelmaking operations to produce carbon steels, as well. Electric arc furnace an overview sciencedirect topics.
The past 5 years have seen increases in the supply and use of pig iron, direct reduced iron dri, and hot riquetted iron hi in. The features of eafs are described in a prior cmp techcommentarytitled introduction to electric arc furnace steelmaking tc1077. The past 5 years have seen increases in the supply and use of pig iron, direct reduced iron dri, and hot riquetted iron hi in the eaf. 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. Electric arc furnace steelmaking is the manufacture of steel from scrap or direct reduced iron melted by electric arcs. Eaf electric arc furnacedc hot fetling at abul khair steel. The situation is not the same in the emerging countries, where scrap is not always available in the required. Arc furnaces range in size from small unitsof approximately one ton capacity used infoundries for producing cast iron productsup to about 400 ton units used for secondarysteelmaking 3. Future green steelmaking technologies sara hornby anderson, gary e.
Quite rightly the initial focus is on securing the existing asset base on a stable footing. Jun 16, 20 electric arc furnaceelectric arc furnace. In the developed world, 100% steel scrap is the most common charge. In an electric arc furnace, a batch of steel heat may be started by loading scrap or direct reduced iron into the furnace, sometimes with a hot heel molten steel from a previous heat.
Steelmaking in electric arc furnace has emerged as an important steelmaking process in recent. An electric arc furnace eaf is a furnace that heats charged material by means of an electric. Lecture 15 electric furnace steelmaking contents nptel. Electric arc furnace industrial efficiency technology. Use of hot riquetted iron hi in the electric arc furnace.
Understanding electric arc furnace steel making operations. The effect on the electric arc furnace steelmaking process parameters by hot metal utilization from 41 to 75% in a 150 tonch furnace has been investigated. 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. Process parameters including oxygen lancing, accumulated power consumption, and tap. Products ironmaking and steelmaking electric arc furnaces. Jones, nupro corporation continued furnace charging melting refining deslagging tapping furnace turnaround top refining refining operations in the electric arc furnace have traditionally involved the removal of phosphorus, sulfur, aluminum, silicon, manganese and carbon from the steel. External arc heating permits better thermal control than does the basic oxygen process, in which heating is accomplished. 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.
At high temperatures, oxygen is blown through the metal, which reduces the carbon content to between 01. The sms demag conarc furnace combines the conventional converter process with electric arc steelmaking in a furnace with two identical shells. Scraps, direct reduced iron, pig iron, and additives are melted through highpower electric arcs formed between a cathode. Eafs are used to produce carbon steels and alloy steels primarily by recycling ferrous scrap. With purely scrap operation at one end of the scale, the electric arc furnace can also be operated with a charge of only 30 % scrap and 70 % liquid hot metal. In electric arc furnace, raw material for iron is not ore or coke, but it just directly uses scrap. The major cost for steel making with eaf is electricity about one. Eafs are versatile, charging everything from all sorts of scrap to hot. In modern eaf operations, especially those operating with a hot heel of molten steel and slag retained from the prior heat, oxygen may be. Using oxygen reaction as electricity saving in electric arc furnace. The predicted total costing shown is not meant to represent an actual cost for any. The electric arc furnace eaf steel production represents about 34% of the.
Hot induction furnace with hell and cover 10% 20% 30% 50% 40% cold induction furnace cold induction furnace without cover. The interior of the shell is lined with two or more layers of carbon blocks. Other steelmaking routes of employing electric arc furnace eaf and processes are stainless steel sts production are also introduced. Corresponding to these processes, a differentiation is made between oxygen steel and electric steel. Over the last 15 years the use of alternative iron sources such as direct reduced iron dri, hot briquetted iron hbi and pig iron have grown domestically to more than 5 million tons per year which.
Blowing oxygen through molten pig iron lowers the carbon content of the alloy and changes it into lowcarbon steel. Comprehensive electric arc furnace electric energy consumption. Only process wherein either oxidizing or reducing condition can be maintained as desired. 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. During the 20052014 period, participation of steel production via electric arc furnace was increased, for example, in italy for 12,3%, in usa for 7,5%, in russia for 14,3%, but a due to. In the electric arc furnace eaf sector, some of these technologies involve the increased use of chemical. Effect of hot metal utilization on the steelmaking process. Electric arc furnaces eafs are a central part of the production route that is an alternative to the dominant bfbof route. The roof is exposed to more heat than other furnace elements. Hot arms can be made from copperclad steel or aluminium. 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. The basic oxygen furnace bof is a refractorylined, tiltable converter into which a vertically movable, watercooled lance is inserted to blow oxygen through nozzles at. The bos process uses pure oxygen, injected by a lance, for refining the relatively impure hot metal and scrap is used for temperature control. The bos method adds recycled scrap steel to the molten iron in a converter.
Higherquality electricarc furnace steel carnegie mellon university. All components are dedicated to cutting the cost of electric steel production. External arc heating permits better thermal control than does the basic oxygen process, in which heating is accomplished by the. Check out the new electric arc furnace being fired up at republic steel in lorain. More than half the worlds steel is produced in the basic oxygen process bop, which uses pure oxygen to convert a charge of liquid blastfurnace iron and scrap into steel. Find highquality stock photos that you wont find anywhere else. What youre seeing here is the arc between the tip of an electrode and liquid steel, which is hidden under nearly a foot of slag the bubbling liquid you. In an eaf scrap andor manufactured iron units such as dri, pig iron, iron carbide is melted and converted into high quality steel by using highpower electric arcs. Electric arc furnace eaf steel making technology is more than hundred years old.
Emerging new technology started in the beginning of the twentieth century when wideranging generation of relatively cheap electric energy started at that time. How eaf steam explosions occur in the fatal accidents described above, and in many others documented as well, there is a common denominator. The second world war saw a steep increase in the use of these furnaces leading to the modern electric arc furnace design operation and working principles. In the traditional electric arc furnace process for producing steel, approximately 20 to 22 pct of the total heat generated is lost in the hot gases emitted from the furnace. 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. Air pollution control of an electric furnace steelmaking shop. In this chapter, a short introduction to most significant progresses, features, and phenomena in electric steelmaking are presented. Nothing succeeds like success with arccess electric arc furnace technology from sms group. Initially, eaf steelmaking was developed for producing special grades of steels using solid forms of feed such as scrap and ferro alloys.
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