Raw products

Coal is a family name for a variety of solid organic fuels and refers to a range of combustible sedimentary rock materials spanning a continuous quality range. For convenience, this continuous series is divided into four categories: 1) anthracite, 2) bituminous coal (metallurgical coal), 3) sub-bituminous coal, 4) lignite.
Coal is the primary fuel used by integrated iron and steel producers.

A solid carbon based product derived from baking bituminous coal at high temperature to remove volatile constituents.
Metallurgical coke ('met coke') is used as the main fuel in the smelting of iron ore in a blast furnace. The quality of coke has a significant influence on furnace productivity and iron production costs.

Iron Ore
Iron ore is formed of rocks, minerals or meteorites from which metallic iron can be extracted.Typically, the iron is in the form of iron oxide, which varies in colour from dark grey, bright yellow and deep purple to rusty red.Iron ore can have up to 65% ferrous content, but is often lower and needs to be refined before use.
Iron ore is the raw material used to make pig iron, which is one of the main raw materials for making steel. 98% of mined iron ore is used to make steel.

Pig Iron
A key intermediate material in the integrated (converter-based) steelmaking process, pig iron is the product of smelting iron ore, coke and limestone in a blast furnace.
Pig Iron is used directly in the manufacture of steel. Merchant pig iron is sometimes used as a substitute for scrap in EAF steelmaking, when there is a need to control residuals.

Direct Reduced Iron (DRI) – or sponge iron – is processed iron ore that is iron-rich enough to be used as a scrap substitute in electric furnace steelmaking. It is made by the reduction (removal of oxygen) of iron oxide (iron ore) at temperatures below the fusion point of iron.
As mini-mills expand their product abilities to sheet steel, they require much higher grades of scrap to approach the quality of output from integrated mills. DRI enables mini-mills to use iron ore without having a blast furnace. It serves as a low residual raw material and alleviates the mini-mills’ dependence on cleaner, higher priced scrap.

Hot Briquetted Iron (HBI) is Direct Reduced Iron that has been processed into briquettes. Instead of using a blast furnace, the oxygen is removed from the ore using natural gas and results in a substance that is 91%–94% iron. Because DRI may spontaneously combust during transportation, HBI is preferred when the metallic material must be stored or moved.
Because of its high iron content and low residual levels, HBI can be used in almost every type of steelmaking operation. It has advantages over steel scrap due to its high bulk density and the very low content of undesirable chemical elements.

Alloys of iron with a high proportion of added elements - such as silicon, nickel, chromium, molybdenum, vanadium and manganese – that are used to improve properties in the production of special steels.
As part of the steel production process, ferro-alloys are added to the usual mix of raw materials to alter the chemistry as required for certain specific end uses. The added elements determine whether the steel will end up as paper clips, a car body, the undercarriage of a jumbo jet, or a beam in a high-rise building.

Steel can be recycled almost indefinitely without losing its properties. Obsolete ferrous scrap is derived from steel-containing goods at the end of their useful lives (e.g.a drinks can, a 15-year-old car, a 50-year-old building). Revert scrap is steel waste produced and recycled within a steelworks. New production scrap is generated when steel is cut and formed during the manufacturing of finished products or components. The scrap is returned to steelworks and foundries.
Ferrous scrap is mainly used in electric arc furnace steelmaking. About 500 million tonnes of scrap are melted each year.

Manganese is used in steel alloys to increase many favourable characteristics such as strength, hardness and durability. In fact steel cannot be produced without manganese; it is an essential ingredient in the process.
Steel becomes harder when it is alloyed with manganese. It has similar applications when alloyed with aluminium and copper. Hardened steel is important in the manufacture of construction materials like L-beams (24% of manganese consumption), machinery (14% of manganese consumption) and transportation products (13% of manganese consumption).

Documentazione Tecnica