红土镍矿深度还原—磁选试验研究

Deep Reduction-magnetic Separation of Laterite-nickel Ore

采用深度还原—弱磁—强磁工艺对低品位红土镍矿进行了开发利用研究,重点研究了深度还原合适的温度、还原时间、配碳系数、料层厚度、强磁精矿返回量等参数。研究表明,适宜的深度还原条件为:还原温度1 275℃、还原时间50 min、配碳系数2.5、料层厚度25 mm、强磁精矿返回量占原矿量的25%,还原产物经弱磁选(场强为130 kA/m),可获得镍、铁品位分别为6.96%、34.74%,镍、铁总回收率分别为94.06%、80.44%的优质镍铁精矿产品;同时富含大量细小镍铁颗粒的强磁精矿是红土镍矿深度还原的优质成核剂。

The low grade nickeliferous laterite ore was treated by deep reduction,low-intensity magnetic separation,high-intensity magnetic separation process,during which reducing temperature,reducing time,carbon coefficient,thickness of materisl-bed and the backing amount of concentration from high-intensity magnetic separation was investigated.The optimal condition were the reduction temperature at 1 275 ℃,reduction time for 50 min,carbon coefficient of 2.5,thickness of material-beds of 25 mm,the backing amount of concentration from high-intensity magnetic separation of 25 percent of ore by weight.The nickel-iron products in high quality with nickel and iron grade of 6.96% and 34.74%,nickel and iron recovery of 94.06% and 80.44% respectively was achieved by low-intensity magnetic separation,the intensity of which was 130 kA/m,at the same time,the concentration riched in micro-nickeliron particles from high-intensity magnetic separation has good qualities in nucleator.