低品质红土镍矿选择性还原-磁选制备镍铁合金

以TFe品位21.70%、Ni品位1.92%的低品位红土镍矿为原料，采用回转窑选择性还原-磁选工艺制备镍铁合金，研究了还原温度、磨矿方式以及磁场强度对镍铁回收率的影响。结果表明，适宜的工艺参数为: 还原温度1150 ℃、细磨(磨矿时间3 min)、磁场强度150 mT，此条件下所得镍铁合金中镍品位7.26%、镍回收率96.06%、铁品位85.15%、铁回收率89.23%，实现了低品位红土镍矿中铁、镍高效回收利用，并且镍铁中碳、磷和硫含量均在要求范围内。

Preparation of Ferronickel Alloy with Low-Grade Nickel Laterite by Selective Reduction and Magnetic Separation

A low-grade nickel laterite grading 21.70% TFe, 1.92% Ni was taken as the raw material to prepare ferronickel alloy with a rotary kiln by using the processing technique consisting of selective reduction and magnetic separation. The effects of reduction temperature, grinding mode and magnetic field intensity on the recovery rates of Ni and Fe were all explored. Results showed that experiment with the following optimal parameters, including reduction temperature of 1150 ℃, fine grinding for 3 min, magnetic field intensity of 150 mT, could produce the ferronickel alloy grading 7.26% Ni and 85.15% TFe at the corresponding recoveries of 96.06% and 89.23%, thus achieving efficient utilizaiton of iron and nickel from low-grade nickel laterite. Besides, the content of carbon, phosphorus and sulfur in the obtained ferronickel is within the required scope.