BRENDA JERNMALMSKULOR MED MAKROPORER JEMTE SETT ATT FRAMSTELLA DESAMMA

摘要

This invention relates to fired iron-ore pellets and a process for producing the same. The process includes the steps of: crushing iron ore to be pelletized; adding carbonaceous materials of grain sizes of 0.1 to 3 mm in diameter to the thus crushed iron ore in an amount of up to 4% by weight for mixing therewith; pelletizing a mixture thus prepared; and firing the pellets thus obtained; thereby providing pellets, in each of which there are intentionally dispersed macro-pores of sizes of 0.1 to 0.3 mm in diameter, at a ratio of up to 25% to the entire pores contained therein. Pellets produced by this process demonstrate superior properties in both high temperatures and in non-temperatures and have a high gas efficiency as well as being free of retardation of reduction even in an elevated temperature range in a blast furnace. These pellets are also free of the softening and sticking phenomena found in the prior art thereby improving the productivity of the blast furnace and reducing the coke ratio.