use of sponge iron in production of cast iron and steel

laboratory and industrial scale experiments are made on the application of sponge iron pellets and briquettes for the production of cast iron and steel in different melting systems, such as electric induction furnace, electric resistance furnace and fuel-fired crucible furnace. effect of various variables such as specifications of sponge iron, temperature of the molten metal and the method of feeding on the melting mechanism of the sponge iron, the melting time of the particles, the chemical composition of the molten metal and the weight of the slag are studied. the results show that batch and continuous feeding operations whih up to 100 percent sponge iron materials are possible with an improvement in the quality of the products. these operations are, however, accompanied with a number of difficulties, such as, the production of an increasing volume of slag and the degradation of the refractories of the furnace. this is a result of the substitution of the iron ingots and the steel scraps, usually used as charge materials, with the sponge iron particles. these difficulties are especially severe when batch feeding operations are employed and if not resolved may cause a decrease in the efficiency of the operation and possible damage to the lining of the furnace.