| 摘要 |
<p>1460852 Reduction of metal oxides SVENSKA KULLAGERFABRIKEN AB 25 Jan 1974 [26 Jan 1973] 03481/74 Heading C7D Metal is extracted from oxides by a process which includes blowing pre-reduced oxide material in a carrier gas into the lower part of a furnace containing a stack of solid reductant, the temperature of that part of the stack being at or above the melting point of the metal. In a preferred embodiment, coke 5 is contained in a shaft furnace 4 while oxygen in pipe 8 and hydrocarbon in pipe 7 is blown in though tuyeres 10; alternatively or additionally, the furnace may be heated electrically, e.g. with plasma burners or through graphite electrodes. Pre-reduced oxidic ore is blown through pipe 21 into the bottom of the furnace using inert or reducing carrier gas and final reduction and melting occur simultaneously to provide molten iron 9. Preferably, outgoing gases 12, a mixture of carbon monoxide and hydrogen, are used to prereduce the oxidic material 16 in a fluidized bed 20, and to dry ingoing oxidic material at 17, and may be recycled to an upper part of the furnace at 30. By using these outgoing gases in the pre-reduction step, the process is self-regulating. The method is particularly applicable to iron ores e.g. haemetite, but it may be applied to ores containing tungsten, chromium, manganese, nickel, copper, cobalt or vanadium.</p> |
