UPGRADING THE NICKEL CONTENT FROM LOW GRADE NICKEL LATERITIC IRON ORES

摘要

The nickel content from low grade nickel lateritic iron ore is upgraded by a combined process of segregation and magnetic separation or flotation. Ground ore is thoroughly mixed with a small quantity of calcium carbonate, calcium sulfate and coke and is sprayed with a solution of sodium chloride to make appropriate pellets. These pellets are gradually heated under a neutral or a slightly reducing atmosphere to a temperature of 1050 DEG C maximum for up to 90 minutes. Roasting at this temperature is carried out for a predetermined period of time so as to convert all the nickel from the ore to a metallic condition. The roasted material is cooled, ground in a water medium and finally subjected to a wet or dry magnetic separation or flotation separation treatment so as to obtain a rich nickel concentrate.