Comparison of direct reduction-magnetic separation process on ferruginous and magnesian laterite ore
(School of Civil and Resource Engineering, University of Science and Technology Beijing, Beijing 100083, China)
Abstract: A contrast study was carried out on the direct reduction-magnetic separation process between ferruginous laterite ore and magnesian laterite ore. The result shows that nickel in ferruginous laterite ore is easier to be reduced and recovered without adding additives. The nickel recovery rate can reach 90%, but nickel grade is low. The nickel in magnesian laterite ore is harder to be reduced and recovered without adding additives. Both nickel grade and recovery rate are not ideal. The nickel recovery rate just can reach 45%. Sodium sulfate can be used as an ideal additive for ferruginous laterite ore sample, while which is not suitable for magnesian laterite ore. The effect of calcium fluoride on magnesian laterite ore is remarkable, but it is not obvious for ferruginous laterite ore. It is found that nickel existing state, the iron content as well as the metal particle size obtained by reduction are the main reasons for above differences between the two kinds of ores.
Key words: ferruginous laterite ore; magnesian laterite ore; direct reduction; magnetic separation