Granulation of Liquid Iron Oct15

Granulation of Liquid Iron...

Granulation of Liquid Iron Granulation of liquid iron is a method of handling of excess production of hot metal in a blast furnace (BF)  which cannot be consumed by steel making in the steel melting shop of an integrated iron and steel plant. It is a cost effective method of producing a solid product which is known as granulated iron (GI). GI has good chemical and physical properties like pig iron and can be used as a prime raw material for the purpose of steel making. GI has a chemical composition identical to the liquid iron which is being granulated. There is no oxidation or slag entrapment in the GI and there is high metallic content. Fig 1 shows some pieces of GI. Fig 1 Granulated iron  A GI plant takes care of any mismatch between the production at the iron making facilities and the requirement of liquid iron at the steel making facilities. It is logistically positioned in between the two facilities. Excess liquid iron from the BF is diverted to the GI plant for the production of GI. This eliminates reduction of hot blast volume at the BF while producing GI which can be used as internal feedstock as coolant in the BOF, or for external sales to be used by the cupolas, induction furnaces (IF) and electric arc furnaces (EAF). GI plants can be constructed and operated with capacities matching with the BF outputs. They are alternative to the pig casting machines (PCM) but with considerable higher capacities. The capacities of even twin strand PCMs are limited due to the solidification time of the liquid iron in the pig moulds. The PCMs also requires frequent mechanical maintenance as a consequence of the complex design. The GI has identical properties to that...