关键词: 印度尼西亚红土镍矿, 硅酸镍, 还原焙烧, 弱磁选, 助熔剂

Abstract: Indonesia low-grade nickel laterite ore contains Ni of 1.57% and Fe of 21.67%,among which nickel exists in form of garnierite.In order to comply with the provisions of Indonesia nickel laterite ore export by increasing the nickel content of above 6%,experiments of reduction roasting and low intensity magnetic separation were carried out with sodium sulfate and sodium carbonate as cosolvent.The test results showed that under conditions of adding 25% reducing coal,the ratio and total amount of sodium sulfate and sodium carbonate at 3∶1 and 20% respectively,roasting temperature at 1 200 ℃ for 60 min,grinding fineness of -0.074 mm 85%,and magnetic field intensity of 96 kA/m,nickel and iron concentrate with yield of 22.06%,Ni grade of 6.05%,Ni recovery of 85.03%,Fe grade of 65.74%,and Fe recovery of 66.92% was obtained.Ni grade in this concentrate is high of the lowest limit for exports of Indonesia laterite nickel ore.

Key words: Indonesia nickel laterite ore, Nickel silicate, Reduction roasting, Low intensity magnetic separation,Cosolvent