Sponge iron, also called direct reduced iron, is the product created when iron ore is reduced to metallic iron, usually with some kind of carbon (charcoal, etc.), at temperatures below the melting point of iron. This results in a spongy mass, sometimes called a bloom, consisting of a mix of incandescent wrought iron and slag. Sponge iron is formed through the reduction of iron ore to metallic iron through reaction with carbon in the form of coal, etc. at approx. 1100 degree Celsius. Sponge iron is also referred to as direct reduced iron, metalized iron, or hot briquetted iron.
Features of sponge iron include
■ Very good reducibility because of high porosity (25-30%)
■ Spherical shape and uniform size give very good bed permeability
■ High strength (150-200 kg) or more for acid pellets
■ Heat consumption is much less than that of sintering
■ High Iron content and uniform chemical composition, hence lower flux, and fuel requirement in the furnace
■ Low FeO
■ Easy handling
■ Its Carbon & FeO is excellent. Steel Mills who are using DRI for reducing the Carbon, the FeO in pellet sponge is less which is major plus point for reducing the Carbon
■ Wearing of inner Lining will not take place, as we are not using Lime in the Pellet making.