从镍精矿中提取镍铁合金的还原工艺

以镍含量为19.5%的镍精矿为原料，采用氧化焙烧-氢气还原-磁选分离的方法制备了镍铁合金粉. 单因素实验表明，增加还原温度和还原时间以及氧化产物平均粒度在2.25 mm左右均有利于镍铁品位的提高，而增加氢气流量不利于镍铁品位的提高. 设计L9(34)正交实验，确定了最佳工艺条件：还原温度900℃，还原时间8 h，氢气流量1.784 mL/s，氧化产物平均粒度2.25 mm. 利用此方法制备出镍品位56.8%、镍铁含量93.2%的镍铁合金粉，Ni回收率为87.0%.

Reduction Technology of Preparation of Ferronickel Powder from Nickel Concentrate

Ferronickel powder was prepared by the processes of oxidation-reduction-magnetic separation. The content of Ni in raw nickel concentrate is 19.5%. Single factor experimental results show that the grade of Ni and Fe in magnetic products can be improved by increasing the reduction temperature and time, the grade of Ni and Fe is the highest when the average particle size of oxidized products is about 2.25 mm, while the grade of Ni and Fe decreases with increasing the flow rate of H2. The optimum technological conditions of reduction processes were obtained through orthogonal experiment L9(34): reduction temperature 900℃, reduction time 8 h，H2 flow rate 1.784 mL/s and average particle size of oxidation products 2.25 mm. The contents of Ni and Ni-Fe are 56.8% and 93.2% in ferronickel alloy powder prepared by this method, respectively. And the recovery rate of Ni is 87.0%.