METHOD OF PRODUCING FERROCHROMIUM FROM LEAN IRON-CONTAINING CHROMIUM ORES Russian patent published in 2001 - IPC

FIELD: production of high-grade ferrochromium. SUBSTANCE: method is realized in successively located melting vessels, for instance, converters. Charged into the first converter is mixture of ore and coal, oxygen is supplied for creation of reducing atmosphere, and mixture is successively melted and heated up to preset temperature. Then metal is tapped from lower part of the first converter, and slag containing 55.0-65.0 wt.% of Cr₂O₃ and 5.0-15.0 wt. % of FeO is directed to the second converter in which slag is subjected to treatment with mixture of oxygen and coal to obtain metal with content of chromium of 65.0-70.0 wt.% and slag with ferrous oxide content of 0.5-1.0 wt. % and chromium oxide of 2.0-3.0 wt.%. Quantity of coal supplied to the first and second converters are determined by claimed formula. EFFECT: development of energy-saving technology of producing ferrochromium with high content of chromium in alloy.