高铁铝土矿直接还原—溶出工艺

提出了一种以Na2CO3为添加剂、以煤为还原剂的还原分离方法,将原矿中铁的氧化物还原为铁单质粉末通过磁选分离回收,将水铝石矿物转化为铝酸钠溶出分离回收.通过单因素实验考察了还原温度、还原时间、Na2CO3用量和还原剂用量对粉末铁品位、铁回收率和氧化铝溶出率的影响,并用X射线衍射分析、扫描电镜观察和能谱分析等方法研究了反应的过程和机理.通过正交试验优化了实验参数,获得的最优条件为还原温度1150℃,还原时间45 min,Na2CO3用量40.47%,还原剂用量11.9%;在最优条件下,粉末铁品位为95.88%,铁回收率为89.92%,氧化铝溶出率为75.92%.

Direct reduction-leaching process for high ferric bauxite

A direct reduction method was proposed which uses soda ash as the flux and coal as the reductant.By using this method hematite is reduced to iron,which can be recovered by magnetic separation,while Al2O3 is translated into sodium aluminate,which can be recovered from the solution.The effects of reduction temperature,reduction time,Na2CO3 dosage and reductant dosage on the grade of iron powder,the recovery of iron powder and the recovery of alumina were investigated on the basis of the single factor alteration principle.The process and reaction mechanism were studied by X-ray diffraction(XRD),scanning electron microscopy(SEM) and energy dispersive spectrometry(EDS).Orthogonal experiments were designed for optimizing the experimental parameters.Under the optimum condition of the reduction temperature of 1 150 ℃,the reduction time of 45 min,the Na2CO3 dosage of 40.47% and the reductant dosage of 11.9%,the grade of iron powder is 95.88%,the recovery of iron powder is 89.92%,and the recovery of alumina is 75.92%.