Blast furnace
it is also named as basic oxygen furnace. it is the a process in which the iron ore is converted into liquid form of iron. iron produced by this method contains high amount of carbon and other impurities. this iron is called pig iron. To make steel products from pig iron it is further processed into BOF(basic oxygen furnace) where its carbon content and other impurities are burnt or removed through slag separation. the main input for the blast furnace is iron ore and coal. basic oxygen furnace is also known as oxygen furnace because oxygen is the only fuel used in this process.
Electric Arc Furnace
in this process the sponge iron is remelted , melting scrap is main inputs to produce finished steel. It uses 400-500 kWh/ton of electricity. ISPAT ,ESSAR and the Jindal group uses this technology.
COREX or Cipcor Process: it is an advance process of making steel. Though few use this process, in melting work . the non-coking coal is used directly for the melting work and it also makes it possible to use lump ore and pellets as inputs. These two advantages allow steel producers to eliminated coking plants and sinter plants. Purpose of coking plant is to convert non-coking coal into more efficient fuel and purpose of sinter plant is purify lump ore or pellets for further processing. Basic inputs to COREX are iron-ore and coal. Jindal Iron & Steel Company (JISCO) uses COREX technology to produce finished steel.
Induction arc furnace(IAF): it is a most advance process in the production os steel.\it also uses electricity as fuel .it is the environment friendly and efficient way to produce steel but its lack of refining capacity requires clean product as its inputs. small steel companies use this technology