Method for processing zinc concentrates

Abstract

According to the present invention there is provided a method for smelting a zinc sulfide concentrate, the method comprising the steps of: feeding the zinc sulfide concentrate to a reduction furnace at a known mass flow rate of sulfur; feeding copper metal to the reduction furnace at a mass flow rate of copper approximately three-times the mass flow rate of sulfur; reducing the zinc sulfide to zinc according to the equation ZnS(l)+2Cu(l)→Cu2S(l)+Zn(g); and fuming the zinc; wherein sulfur is absorbed into the copper metal in the reduction furnace to form a copper sulfide molten matte. The partial pressure of SO2 in the furnace is maintained below about 10−3 atm and the reduction furnace is operated at a temperature of between about 1240 and about 1300° C.

Dependencies are inferred from the claim text.