从红土镍矿中提取镍钴铁的新工艺研究

针对云南省元江红土镍矿的矿物组成特点,在比较国内外红土镍矿处理工艺的基础上,提出了还原—磨矿—选别—氧化浸出工艺处理该矿,并进行了全流程试验。首先进行了还原—磨矿—选别试验研究,主要考察了还原温度、还原时间、添加剂配比和还原剂配比对指标的影响;其次进行了综合试验。试验结果表明,还原—磨矿—选别可以抛弃红土镍矿中80%以上的脉石,同时实现镍钴铁富集,氧压浸出工艺可实现镍钴与铁的分离,并获得铁红产品。通过试验,获得的技术指标为:从原矿至氢氧化镍(钴)段,镍直收率大于75%、钴直收率大于70%和铁直收率大于80%;氢氧化镍产品镍的品位大于31%,氢氧化钴产品钴的品位大于0.70%,铁红产品铁含量大于62%,铁红达到铁精矿要求,可以作为铁精矿出售。该工艺实现了镍钴铁综合回收,资源利用率高,环境友好,为综合回收红土镍矿中镍钴铁提供一条新的工艺技术路线。

Study on a novel process to extract the nickel, cobalt and iron from the laterites ore

In view of the mineral composition of Yuanjiang laterite in Yunnan province,based on the laterite processing comparison at home and abroad,a novel process route of extracting the nickel,cobalt and iron from this ore by reduction—grinding—seperation—oxidation leaching is proposed and full flow test has been implemented.Firstly,the experiment of reduction—grinding—separation is conducted,during which,the impacts from reduction temperature,reduction time,additive ratio to the index are mainly investigated;secondly,the comprehensive experiment is conducted.The results show that more than 80% of the gangue from laterite ore can be discarded while the nickel,cobalt and iron of laterite ore is concentrated at the stage of reduction—grinding—separation;nickel-cobalt separation from iron and obtain iron product can be realized by oxidation leaching.Through the experiments,the technical indexes are obtained as following: at the stage between raw ore to nickel hydroxide(cobalt hydroxide),the direct recovery of nickel is larger than 75%,cobalt larger than 70%,and iron larger than 80%.In the production of nickel hydroxide,the grade of nickel is over 31%,the grade of cobalt in cobalt hydroxide is over 0.7%,and iron over 62%,which reaches the requirement of iron concentrate and can be selled as iron concentrate.This process realized the comprehensive recovery of nickel,cobalt and iron with high resource utilization rate and is environment friendly process,which provides a new process route for comprehensive recovering nickel,cobalt and iron from laterite ore.