Ultra-high pressure briquetting of sponge iron fines
Sponge iron has a strong tendency to spontaneously ignite due to its high porous structure, which needs passivation by way of briquetting to facilitate storage, long distance transportation & proper melting. For cold pressing of sponge iron, specific pressures in the range between 10,000 to 11,000 kgs/cm are required.
Sponge iron briquettes can be advantageously used in place of sponge iron fines(0-3 mm size) for melting. With higher density up to 5 grams/cc, they penetrate deeper into the induction furnace / electric arc furnace & melt completely. In the presence of adequate carbon in the melt, most of the FeO in the sponge iron briquettes will get converted into Fe.
Briquetting of sponge iron fines increases the melting capacity of the induction furnace & reduces the dust and metal losses. They cannot be oxidised easily on the surface. Since the briquettes are dense, they are heavy & their melting rates are high.
Use of sponge iron briquettes in place of sponge iron fines will result in higher steel recovery, lower energy consumption, lower cost of melting, lower slag formation & higher lining life.
Goodrich offers ultra-high pressure roller briquetting press lines for sponge iron fines. The plant capacities are from 100 tons per day to 320 tons per day and the investments are from Rs. 2.50 crores to Rs. 8 crores. The pay-back periods are 1-2 years.
