| 摘要 |
<p>1328198 Selective reduction of Ni and Fe bearing ores SHERRITT GORDON MINES Ltd 19 April 1971 [10 Feb 1970] 23926/71 Heading C7D Finely divided particles of oxidic nickel and iron bearing ore are treated in suspension in a gas stream containing sufficient gaseous reductant to reduce the nickel oxides (and cobalt oxides if present) in the suspended ore particles to a form soluble in a leach solution, and also to reduce the iron oxide constituent therein to magnetite, whilst passing the suspension through a reaction zone at 370-925‹C for # 15 secs; reducing agent/ore ratio and temperature being controlled such that the process is accompanied by a minimum reduction of iron values to metallic iron. The carrier gas may contain H 2 or CO as reducing agent, and may be produced by reforming naphtha or by partial combustion of heavy fuel oil. As shown carrier gas is supplied via conduit 20 to the reactor 10, e.g. formed by a stainless steel pipe, particulate ore being provided thereto by hopper 25 and conveyer 24, the suspension passing upwards through reaction zone 12 heated by combustion chamber 14 and hence via outlet 30 to scrubber 32 (or alternatively to a cyclone or electrostatic precipitator) where the ore is separated from the gas stream. Unreacted reducing agent may be recycled, other hot gases being otherwise utilized.</p> |
