GB979760A - Process for the preliminary treatment of iron ore - Google Patents

Abstract

Lumpy or powdery iron ore, e.g. magnetite, haematite or iron hydroxide, is preliminary treated prior to smelting, e.g. in a blast furnace, by reducing it with a reducing agent, such as non-coking, bituminous or hard coal, charcoal, natural or electric furnace gas or petroleum, in a furnace, preferably a rotary kiln or shaft furnace, at a temperature of at least 1000 DEG C. but at which no fusion or only slight surface fusion of the ore particles takes place, e.g. 1000-1250 DEG C., to a degree such that the resulting sponge iron material, being of the same form as the original ore in the case of a lumpy ore and comprising lumps resulting from cohesion in the case of powdery ore, contains FeO and Fe and less than 5% Fe2O3. Fluxing agents for the subsequent smelting, e.g. limestone, manganese ore or bauxite, may be initially incorporated with the iron ore. The product may contain 33-50% FeO.ALSO:Lumpy or powdery iron ore, e.g. magnetite, haematite or iron hydroxide, is preliminarily treated prior to smelting, e.g. in a blast furnace, by reducing it with a reducing agent, such as non-coking, bituminous or hard coal, charcoal, natural or electric furnace gas or petroleum, in a furnace, preferably a rotary kiln or shaft furnace, at a temperature of at least 1000 DEG C. but at which no fusion or only slight surface fusion of the ore particles takes place, e.g. 1000-1250 DEG C., to a degree such that the resulting sponge iron material, being of the same form as the original ore in the case of a lumpy ore and comprising lumps resulting from cohesion in the case of powdery ore, contains FeO and Fe and less than 5% Fe2O3. Fluxing agents for the subsequent smelting, e.g. limestone, manganese ore or bauxite, may be initially incorporated with the iron ore.