Misplaced Pages

#407592

25-650: Weirton Steel Corporation was an integrated steel mill founded in 1909 by Ernest T. Weir. In 1905, Weir and his partner, James Phillips, bought a tin mill in Clarksburg, West Virginia . In 1909, they relocated to Hollidays Cove , West Virginia , and expanded the operation. The location was chosen due to the abundant water supply, much needed for steel production, and the convenient access to major steel markets. In 1929, Weir merged Weirton Steel with Detroit's Michigan Steel and Cleveland's M. A. Hanna Company to form National Steel Corporation . National Steel became one of

50-709: A rolling mill . Originally the minimill was adapted to production of bar products only, such as concrete reinforcing bar , flats, angles, channels, pipe, and light rails. Since the late 1980s, successful introduction of the direct strip casting process has made minimill production of strip feasible. Often a minimill will be constructed in an area with no other steel production, to take advantage of local markets, resources, or lower-cost labour. Minimill plants may specialize, for example, in making coils of rod for wire-drawing use, or pipe, or in special sections for transportation and agriculture. Capacities of minimills vary: some plants may make as much as 3,000,000 tons per year,

75-483: A few hours, the accumulated liquid iron is tapped from the blast furnace and either cast into pig iron or directed to other vessels for further steel making operations. Historically the Bessemer process was a major advancement in the production of economical steel, but it has now been entirely replaced by other processes such as the basic oxygen furnace . Molten steel is cast into large blocks called blooms . During

100-416: A low offer of $ 237 million. On April 22, 2004, U.S. federal bankruptcy Judge L. Edward Friend II ruled that ISG could purchase Weirton Steel. By court order, the assets were then auctioned, with most being acquired by ISG, which formed a new division called ISG Weirton Steel . On April 5, 2005, ISG completed a merger with Mittal Steel . In 2006, Mittal Steel completed a further merger with Arcelor , forming

125-733: A new company known as ArcelorMittal . In December 2020, ArcelorMittal sold its U.S. holdings to Ohio-based Cleveland-Cliffs Inc. making it a subsidiary of the Cleveland-Cliffs organization. On February 15, 2024, Cleveland-Cliffs announced that it would shut down the Weirton tinworks on April 16th, with CEO Lourenco Goncalves stating that the United States International Trade Commission overturning an earlier Department of Commerce ruling allowing for higher tariffs on tinplate imports rendered

150-513: A regular basis, minimills can follow the market demand for their products easily, operating on 24-hour schedules when demand is high and cutting back production when sales are lower. Direct reduced iron Direct reduced iron ( DRI ), also called sponge iron , is produced from the direct reduction of iron ore (in the form of lumps, pellets, or fines) into iron by a reducing gas which contains elemental carbon (produced from natural gas or coal ) and/or hydrogen . When hydrogen

175-438: A time. The following reactions successively convert hematite (from iron ore ) into magnetite , magnetite into ferrous oxide , and ferrous oxide into iron by reduction with carbon monoxide or hydrogen . Carburizing produces cementite (Fe 3 C): India is the world’s largest producer of direct-reduced iron. Sponge iron is not useful by itself, but can be processed to create wrought iron or steel. The sponge

200-457: A typical size is in the range 200,000 to 400,000 tons per year, and some old or specialty plants may make as little as 50,000 tons per year of finished product. Nucor Corporation , for example, annually produces around 9,100,000 tons of sheet steel from its four sheet mills, 6,700,000 tons of bar steel from its 10 bar mills and 2,100,000 tons of plate steel from its two plate mills. Since the electric arc furnace can be easily started and stopped on

225-412: Is a stub . You can help Misplaced Pages by expanding it . Steel mill A steel mill or steelworks is an industrial plant for the manufacture of steel . It may be an integrated steel works carrying out all steps of steelmaking from smelting iron ore to rolled product, but may also be a plant where steel semi-finished casting products are made from molten pig iron or from scrap . Since

250-447: Is removed from the furnace, called a bloomery, and repeatedly beaten with heavy hammers and folded over to remove the slag, oxidize any carbon or carbide, and weld the iron together. This treatment usually creates wrought iron with about three percent slag and a fraction of a percent of other impurities. Further treatment may add controlled amounts of carbon, allowing various kinds of heat treatment (e.g. "steeling"). Today, sponge iron

275-416: Is sometimes used with scrap, to help maintain desired chemistry of the steel, though usually DRI is too expensive to use as the primary raw steelmaking material. A typical mini-mill will have an electric arc furnace for scrap melting, a ladle furnace or vacuum furnace for precision control of chemistry, a strip or billet continuous caster for converting molten steel to solid form, a reheat furnace and

SECTION 10

#1732791993408

300-640: Is the pollution produced in the manufacture of coke , which is an essential intermediate product in the reduction of iron ore in a blast furnace. Integrated mills may also adopt some of the processes used in mini-mills, such as arc furnaces and direct casting, to reduce production costs. A minimill is traditionally a secondary steel producer; however, Nucor (one of the world's largest steel producers) and Commercial Metals Company (CMC) use minimills exclusively. Usually it obtains most of its iron from scrap steel, recycled from used automobiles and equipment or byproducts of manufacturing. Direct reduced iron (DRI)

325-421: Is used as the reducing gas no carbon dioxide is produced. Many ores are suitable for direct reduction. Direct reduction refers to solid-state processes which reduce iron oxides to metallic iron at temperatures below the melting point of iron. Reduced iron derives its name from these processes, one example being heating iron ore in a furnace at a high temperature of 800 to 1,200 °C (1,470 to 2,190 °F) in

350-482: The blast furnace grow cold, though some adjustment of the production rate is possible. Integrated mills are large facilities that are typically only economical to build in 2,000,000-ton per year annual capacity and up. Final products made by an integrated plant are usually large structural sections, heavy plate, strip, wire rod, railway rails , and occasionally long products such as bars and pipe . A major environmental hazard associated with integrated steel mills

375-472: The casting process various methods are used, such as addition of aluminum , so that impurities in the steel float to the surface where they can be cut off the finished bloom. Because of the energy cost and structural stress associated with heating and cooling a blast furnace, typically these primary steel making vessels will operate on a continuous production campaign of several years duration. Even during periods of low steel demand, it may not be feasible to let

400-464: The difficulties of conventional blast furnaces . DRI plants need not be part of an integrated steel plant, as is characteristic of blast furnaces. The initial capital investment and operating costs of direct reduction plants are lower than integrated steel plants and are more suitable for developing countries where supplies of high grade coking coal are limited, but where steel scrap is generally available for recycling. Many other countries use variants of

425-555: The facility unprofitable to operate. Over 900 employees are affected by the closure of this facility. U.S. Senator Joe Manchin declared the ITC turned "a blind eye to nearly 1,000 hard-working employees," and that "Cleveland-Cliffs’ closure is an absolute injustice not only to American workers, but to the very principle of fair competition, and it will undoubtedly weaken our economic and national security." Located in Weirton, West Virginia ,

450-466: The integrated steel mill had four blast furnaces (1919, 1926, 1941 and 1952), an open-hearth shop (1920) and a bessemer converter (1936). It was one of the world's largest producers of tin plate products. A basic oxygen plant was constructed in 1965. In May 2023, Form Energy began building a manufacturing facility producing iron-air batteries for electrical storage at the Weirton mill site. This United States manufacturing company–related article

475-600: The invention of the Bessemer process , steel mills have replaced ironworks , based on puddling or fining methods. New ways to produce steel appeared later: from scrap melted in an electric arc furnace and, more recently, from direct reduced iron processes. In the late 19th and early 20th centuries the world's largest steel mill was the Barrow Hematite Steel Company steelworks located in Barrow-in-Furness , United Kingdom . Today,

500-463: The largest steel producers in the United States , but by the end of the century, the company was experiencing financial difficulties. Weirton Steel became the largest Employee Stock Ownership Plan (ESOP) steel plant in the world when employees purchased stocks in the 1980s. After Weirton Steel filed for bankruptcy, with 3,000 employees, Ohio -based International Steel Group (ISG) submitted

525-489: The ore to metallic iron, without melting it (below 1,200 °C (2,190 °F)). The direct reduction process is comparatively energy efficient. Steel made using DRI requires significantly less fuel, in that a traditional blast furnace is not needed. DRI is most commonly made into steel using electric arc furnaces to take advantage of the heat produced by the DRI product. Direct reduction processes were developed to overcome

SECTION 20

#1732791993408

550-400: The presence of the reducing gas syngas , a mixture of hydrogen and carbon monoxide , or pure hydrogen. Direct reduction processes can be divided roughly into two categories: gas-based and coal-based. In both cases, the objective of the process is to remove the oxygen contained in various forms of iron ore (sized ore, concentrates, pellets, mill scale, furnace dust, etc.) in order to convert

575-472: The process. Factors that help make DRI economical: Direct reduced iron is highly susceptible to oxidation and rusting if left unprotected, and is normally quickly processed further to steel. The bulk iron can also catch fire (it is pyrophoric ). Unlike blast furnace pig iron , which is almost pure metal, DRI contains some siliceous gangue (if made from scrap, not from new iron from direct reduced iron with natural gas), which needs to be removed in

600-502: The steel-making process. Producing sponge iron and then working it was the earliest method used to obtain iron in the Middle East , Egypt , and Europe , where it remained in use until at least the 16th century. The advantage of the bloomery technique is that iron can be obtained at a lower furnace temperature, only about 1,100 °C or so. The disadvantage, relative to a blast furnace, is that only small quantities can be made at

625-461: The world's largest steel mill is in Gwangyang , South Korea . An integrated steel mill has all the functions for primary steel production: The principal raw materials for an integrated mill are iron ore, limestone, and coal (or coke). These materials are charged in batches into a blast furnace where the iron compounds in the ore give up excess oxygen and become liquid iron. At intervals of

#407592