Ferrous Metals
The basic materials used in production of steel are iron ore, coking coal, limestone and dolomite. Iron ore are rocks found in the form of hematite or magnetite which are mined and crushed into small particles. Almost all worlds iron ore production is used for making of iron and steel. The coking coal is crushed, screened, and heated in the coke oven to produce high carbon coke for use in the blast furnace and its high level of heat releases iron from iron ore and other impurities. Limestone main function is to remove impurities from molten iron; by chemical reaction in which limestone acts like flux causing impurities to melt at low temperature and mixing with impurities forming slag which floats over the molten iron. The above mentioned basic materials are fed into the blast furnace from the top whilst the heated and pressurised air is blown from the below causing chemical reaction in which the iron being extracted from the iron ore resulting in molten metal or liquid iron ore. Further processing of the molten metal is required as it contains small amount of carbon and other impurities through basic oxygen furnace where the carbon content and impurities are reduced resulting in liquid steel. The liquid steel is then cast into various shapes, forms and sizes for further production using rolling mills.