从阿尔巴尼亚红土矿中综合回收镍钴铁

COMPREHENSIVE RECOVERY OF NICKEL,COBALT AND IRON FROM ALBANIAN LATERITE

用还原—氨浸法处理阿尔巴尼亚红土矿,合理可行,达到了镍、钴、铁综合利用目的。在规模为84吨/日的工业试验中,成功地应用了高效的两段沸腾炉作还原焙烧;三段逆流浸出和流态化洗涤,获得了较佳的镍、钴浸出率。按焙砂特点,合理控制氨浸中可溶铁的相变和相组成,用简便的磁选法回收铁精矿。镍钴提纯时采用硫酸铵溶解和低温氧化水解具较优经济效果;用氢还原工艺直接生产高纯镍粉和钴粉,技术上是先进的。按此试验成果,1978年在阿尔巴尼亚建成了一座年处理90万吨红土矿的镍钴提纯厂。

The treatment of Albanian laterite by reduction-ammoniacal leaching process is reasonable and feasible,and the objective of comprehensive utilization of the elements nickel,cobalt and iron has been achieved. In a series of commercial experiments for a scale of 84 T/day,a high efficiency two-stage fluidized bed roaster was successfully used for reduction roasting;three- stage countercurrent leaching and fluidized washing were conducted and good extractions for nickel and cobalt were obtained.According to the characteristics of the calcines, the phase change and the phase composition of the soluble iron during ammoniacal leaching were rationally controlled and the recovery of iron concentrate was achieved by the simple magnetic separation process.In the purification of nickel and cobalt, ammonium sulphate was adopted for the dissolution operation and the oxydrolysis was performed at low temperatures,the economic aspect was,therefore,satisfactory;high- purity nickel powder and cobalt powder were directly produced by the hydrogen reduction technique.This method was technically advanced. Based on the results of these experiments,in 1978,a nickel and cobalt extraction and purification plant with a capacity of 900,000 T/year laterite has been completed in Albania.