硫酸化焙烧-浸出法处理镍红土矿工艺研究

Study on treatment technology of nickel laterites with sulfation-roasting-leaching method

采用硫酸化焙烧-浸出法,对从镍红土矿中提取镍、钴进行了实验研究.主要考察了酸料比、含水率、焙烧温度、焙烧时间及活化剂加入量等因素,对红土矿中镍、钴、铁浸出率的影响.结果表明,在酸料比为0.4、含水率为40%及活化剂Na2SO4加入量为2-3 g的条件下,采用在400℃下预焙烧20 min,再在700℃下焙烧90 min,在80℃下搅拌水浸1 h,镍的浸出率为85%,钴的浸出率为95%,铁的浸出率在5%以下.

The process of extracting nickel and cobalt from nickel laterites with sulfation-roasting-leaching method was investigated.The influences of the acid/material ratio,the rate of water content,roasting temperature,roasting time,the amount of active agent on the leaching rate of nickel,cobalt and iron were studied experimentally.The results showed that under the acidizing conditions of the acid/material ratio 0.4 and moisture content 40%,the nickel leaching rate reached 85%,the cobalt leaching rate reached 95%,and the iron leaching rate was below 5% by using two-stage roasting process of pre-roasting at 400 ℃ for 20 minutes and roasting at 700 ℃ for 90 minutes with adding 2-3 g Na2SO4,leaching with water at 80 ℃ for 1 hour.