针对目前红土镍矿碱法处理过程中存在的问题提出工艺改进,研究低品位红土镍矿焙烧活化-碱浸过程中含硅矿物的转化。考察了焙烧温度对红土镍矿活性的影响,探索了红土镍矿经焙烧后碱浸过程中温度、时间、搅拌强度、液固比以及碱初始质量浓度对硅转化的影响。结果表明,红土镍矿经650°C焙烧2h后,活性得到明显提高,红土镍矿经焙烧后采用初始质量浓度为60g/L的碱溶液,在搅拌速度为400r/min、浸出温度为140°C、液固比为5∶1的条件下浸出120min,硅的转化率可达89.42%。
A process improvement is proposed in view of the existing problems in alkali treating process of nickel laterite ore,and the transformation of silicon containing minerals during roasting and alkali leaching process of lowgrade nickel laterite ore is researched.The effect of roasting temperature on the activity of nickel laterite ore is studied,and the effects of different variables,such as the leaching temperature,the leaching time,the alkali initial concentration,the stirring intensity and the liquid/solid ratio on the transformation of silicon are investigated.The results showed that the activity of nickel laterite ore is improved significantly after roasting 2hat 650°C,and the transformation rate of silicon can reach 89.42% when the roasted ores are leached by an alkali solution of 60g/L initial concentration at140°C for 120 min under the condition of the stirring intensity at 400r/min and the liquid/solid ratio at 5∶1.