还原-磨选从高镁低品位红土镍矿中回收镍铁

采用还原-磨选工艺对高镁低品位红土镍矿制备镍铁合金粉进行了研究。考察了还原温度、还原时间、原料粒度区间、还原剂用量、添加剂用量等因素对镍直收率的影响。研究结果表明, 合适的还原制度为: 原料粒度0.09～0.12 mm、还原剂用量3%、添加剂用量2.5%, 还原温度1 300 ℃, 还原时间3.0 h。还原产物经球磨、磁选后, 获得镍品位为7.0%以上的镍铁合金粉, 镍直收率87%以上, 实现了从高镁低品位红土镍矿中回收镍铁的目的。

Recovery of Ni and Fe from Low-grade Nickeliferous Laterite Ore with High Magnesium Content by Reduction-Grinding-Magnetic Separation

A low-grade nickeliferous laterite ore with high magnesium content, the raw material for Ni-Fe alloy powder production, was beneficiated by a method of reduction-grinding-magnetic separation. The effects of reduction temperature, reduction time, feed size, reductant dosage, additive dosage on the direct recovery of nickel were discussed. The results show that, reasonable conditions were determined as follows: feed size of 0.09～0.12 mm, reductant dosage of 3%, additive dosage of 2.5%, reduction temperature of 1 300 ℃ and reduction time of 3.0 h. After a further ball milling and magnetic separation, a Ni-Fe alloy with Ni content and recovery of over 7% and over 87%, respectively, can be obtained, showing that it can be achieved to recover Ni-Fe from low-grade nickeliferous laterite with high magnesium content.