PROCESS FOR PRODUCING IRON-POOR NICKEL SULPHIDE MATTE FROM SULPHIDIC NICKEL CONCENTRATES IN THEIR SUSPENSION SMELTING

摘要

1347412 Reducing nickel ores OUTOKUMPU O Y 19 April 1971 [10 April 1970] 26601/71 Addition to 1291911 Heading C7D In the flash smelting of Ni or Ni/Cu sulphidic concentrates in which the concentrates are passed down a reaction shaft together with slag forming ingredients and oxidizing gases into a sedimention zone where slag and matte accumulate, and gases are exhausted through a rising fire, the gases at the lower end of the shaft are made reducing, e.g. by injecting light petrol or sulphur, so that the iron content of the slag is mainly in bivalent form, and the nickel content of the dust in the shaft is reduced to metallic Ni or Ni sulphide. The feed to the top of the shaft may comprise a Ni concentrate, a Cu-Ni residue, and sand, with or without recirculated dust. The temperature at the lower end may be 1350-1450‹C, or higher, e.g. 1600‹C if less fuel is used and O 2 is also injected at this point.