Wrought iron is an iron alloy with a very low carbon content in contrast to that of cast iron. It is a semi-fused mass of iron with fibrous slag inclusions, which give it a wood-like "grain" that is visible when it is etched, rusted, or bent to failure. Wrought iron is tough, malleable, ductile, corrosion resistant, and easily forge welded, but is more difficult to weld electrically.
Iron ores are rocks and minerals from which metallic iron can be economically extracted. The ores are usually rich in iron oxides and vary in color from dark grey, bright yellow, or deep purple to rusty red. The iron is usually found in the form of magnetite (Fe
3O
4, 72.4% Fe), hematite (Fe
2O
3, 69.9% Fe), goethite (FeO(OH), 62.9% Fe), limonite (FeO(OH)·n(H2O), 55% Fe), or siderite (FeCO3, 48.2% Fe).
Steelmaking is the process of producing steel from iron ore and/or scrap. Steel has been made for millennia, and was commercialized on a massive scale in the 1850s and 1860s, using the Bessemer and Siemens-Martin processes.
The general term slag may be a by-product or co-product of smelting (pyrometallurgical) ores and recycled metals depending on the type of material being produced. Slag is mainly a mixture of metal oxides and silicon dioxide. Broadly, it can be classified as ferrous, ferroalloy or non-ferrous/base metals. Within these general categories, slags can be further categorized by their precursor and processing conditions. Slag generated from the EAF process can contain toxic metals, which can be hazardous to human and environmental health.
A blast furnace is a type of metallurgical furnace used for smelting to produce industrial metals, generally pig iron, but also others such as lead or copper. Blast refers to the combustion air being supplied above atmospheric pressure.
Nucor Corporation is an American company based in Charlotte, North Carolina, that produces steel and related products. It is the largest steel producer in the United States and the largest recycler of scrap in North America. Nucor is the 16th-largest steel producer in the world. Along with Commercial Metals Company, it is one of two primary suppliers of rebar used to reinforce concrete in buildings, bridges, roads, and infrastructure in the U.S.
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.
An electric arc furnace (EAF) is a furnace that heats material by means of an electric arc.
Ferroalloy refers to various alloys of iron with a high proportion of one or more other elements such as manganese (Mn), aluminium (Al), or silicon (Si). They are used in the production of steels and alloys. The alloys impart distinctive qualities to steel and cast iron or serve important functions during production and are, therefore, closely associated with the iron and steel industry, the leading consumer of ferroalloys. The leading producers of ferroalloys in 2014 were China, South Africa, India, Russia and Kazakhstan, which accounted for 84% of the world production. World production of ferroalloys was estimated as 52.8 million tonnes in 2015.
Direct reduced iron (DRI), also called sponge iron, is produced from the direct reduction of iron ore into iron by a reducing gas which contains elemental carbon and/or hydrogen. When hydrogen is used as the reducing gas no carbon dioxide is produced. Many ores are suitable for direct reduction.
Kaiser Steel was a steel company and integrated steel mill near Fontana, California. Industrialist Henry J. Kaiser founded the company on December 1, 1941, and workers fired up the plant's first blast furnace, named "Big Bess" after Kaiser's wife, on December 30, 1942. Then in August 1943, the plant would produce its first steel plate for the Pacific Coast shipbuilding industry amid World War II.
Cornwall Iron Furnace is a designated National Historic Landmark that is administered by the Pennsylvania Historical and Museum Commission in Cornwall, Lebanon County, Pennsylvania in the United States. The furnace was a leading Pennsylvania iron producer from 1742 until it was shut down in 1883. The furnaces, support buildings and surrounding community have been preserved as a historical site and museum, providing a glimpse into Lebanon County's industrial past. The site is the only intact charcoal-burning iron blast furnace in its original plantation in the Western Hemisphere. Established by Peter Grubb in 1742, Cornwall Furnace was operated during the American Revolution by his sons Curtis and Peter Jr. who were major arms providers to George Washington. Robert Coleman acquired Cornwall Furnace after the Revolution and became Pennsylvania's first millionaire. Ownership of the furnace and its surroundings was transferred to the Commonwealth of Pennsylvania in 1932.
A cupola or cupola furnace is a melting device used in foundries that can be used to melt cast iron, Ni-resist iron and some bronzes. The cupola can be made almost any practical size. The size of a cupola is expressed in diameters and can range from 1.5 to 13 feet. The overall shape is cylindrical and the equipment is arranged vertically, usually supported by four legs. The overall look is similar to a large smokestack.
The Duluth Works was an industrial steel and cement manufacturing complex located in Duluth, Minnesota, United States, in operation from 1916 to 1981. The complex was operated by the U.S. Steel. Officially, the plant's purpose was to supply the growing Midwest with steel finished products. Unofficially, they were built as part of a "gentleman's agreement" between U.S. Steel and the State of Minnesota to not impose hefty iron ore taxes on U.S. Steel in exchange for a fully integrated steel plant within Minnesota, whose mines furnished 80% of the ore to U.S. Steel. The combined works of the steel and cement plant were the largest employers in Duluth and the fourth largest industrial complex in Minnesota.
JSW Steel Limited is an Indian multinational steel producer based in Mumbai and is a flagship company of the JSW Group. After the merger of Bhushan Power & Steel, Ispat Steel and Jindal Vijayanagar Steel Limited, JSW Steel became India's second largest private sector steel company.
Sinter plants agglomerate iron ore fines (dust) with other fine materials at high temperature, to create a product that can be used in a blast furnace. The final product, a sinter, is a small, irregular nodule of iron mixed with small amounts of other minerals. The process, called sintering, causes the constituent materials to fuse to make a single porous mass with little change in the chemical properties of the ingredients. The purpose of sinter are to be used converting iron into steel.
Plants for the production of lead are generally referred to as lead smelters. Primary lead production begins with sintering. Concentrated lead ore is fed into a sintering machine with iron, silica, limestone fluxes, coke, soda ash, pyrite, zinc, caustics or pollution control particulates. Smelting uses suitable reducing substances that will combine with those oxidizing elements to free the metal. Reduction is the final, high-temperature step in smelting. It is here that the oxide becomes the elemental metal. A reducing environment pulls the final oxygen atoms from the raw metal.
The US iron and steel industry has paralleled the industry in other countries in technological developments. In the 1800s, the US switched from charcoal to coal in ore smelting, adopted the Bessemer process, and saw the rise of very large integrated steel mills. In the 20th century, the US industry successively adopted the open hearth furnace, then the basic oxygen steelmaking process. Since the American industry peaked in the 1940s and 1950s, the US industry has shifted to small mini-mills and specialty mills, using iron and steel scrap as feedstock, rather than iron ore.
The Iron and Steel industry in India is among the most important industries within the country. India surpassed Japan as the second largest steel producer in January 2019. As per worldsteel, India's crude steel production in 2018 was at 106.5 million tonnes (MT), 4.9% increase from 101.5 MT in 2017, which means that India overtook Japan as the world's second largest steel production country. Japan produced 104.3 MT in year 2018, decrease of 0.3% compared to year 2017.
A metallurgical furnace, often simply referred to as a furnace when the context is known, is an industrial furnace used to heat, melt, or otherwise process metals. Furnaces have been a central piece of equipment throughout the history of metallurgy; processing metals with heat is even its own engineering specialty known as pyrometallurgy.
