METHOD FOR PRODUCING BATTERY-GRADE NICKEL SULFATE BY MEANS OF LATERITE NICKEL ORE

摘要

Disclosed is a method for producing a battery-grade nickel sulfate by means of laterite nickel ore. The method comprises the following steps: a laterite nickel ore is sorted to obtain a lump ore and a mud and sand ore; the lump ore is crushed, and is then subjected to a dump leaching treatment to obtain a crude nickel sulfate solution A; the mud and sand ore is separated to obtain a high-chromium ore, a low-iron and high-magnesium ore, and a high-iron and low-magnesium ore, and the low-iron and high-magnesium ore is dried, calcined, reduced and sulfurated to obtain a low nickel matte; the low nickel matte is subjected to blowing, water extraction and then oxygen pressure leaching to obtain a crude nickel sulfate solution B; the high-iron and low-magnesium ore is subjected to pressure leaching to obtain a crude nickel sulfate solution C; and the crude nickel sulfate solutions A, B and C are extracted, and then subjected to evaporative crystallization so as to obtain a battery-grade nickel sulfate. In the present invention, the advantages of the RKEF process, the pressure leaching process and the dump leaching process are fully utilized, and are integrated together to complement one another. The characteristics of different ores are utilized, proper processes are used for treatment, the production cost is low, and the comprehensive recovery rate of nickel and cobalt is 90% or above.