Direct redn. of iron ore powder or oxidised iron dust - mixed with coal and heated in closed reactor to make iron sponge

摘要

The powder or dust is mixed with sufficient coal to cause complete redn. and to obtain a desired % C in the iron. The mixt. is heated in 1.5-2 h to 800-900 deg.C in a closed reactor using external heating; and the combustible gases (I) produced in the reaction are collected, whereas iron sponge shot or pellets are obtd. for further processing. Part of gases (I) is pref. used for external heating of the reactors and for preheating air for the combustion of gases (I). The pref. reactors consist of a row of shafts, 4-6 m high x 0.5 m dia., the middle zones of the shafts being inside a furnace. Used in mfr. of iron from powdered ore or dusts in countries which have no coal suitable for mfg. coke, and/or cannot use large, economic blast furnaces; and where natural gas is not required.