从刚果(金)铜萃余液中回收钴和铜及萃余液的循环利用

Cycling Utilization of Copper and Cobalt Recovered from the Extraction Raffinate of Copper in Congo(Kinshasa)

为了从刚果(金)某湿法炼铜厂铜萃余液中回收钴和铜,并实现萃余液的循环利用,采用除铁—沉铜—第一段沉淀钴—第二段沉淀钴工艺流程处理含钴铜萃余液。结果表明,采用该工艺分别得到铁渣、铜渣、粗氢氧化钴和第二段钴渣,铁渣中钙含量26.79%、铜含量0.05%、钴含量0.12%,除铁过程中铜和钴损失率分别为4.64%和3.14%;铜渣含铜3.74%、含钴2.06%;粗氢氧化钴中钴含量32.83%;第二段钴渣含钴7.14%;钴总回收率大于95%。铁渣用于建筑材料,铜渣返回浸出系统回收铜和钴,粗氢氧化钴可直接外售,第二段钴渣经萃余液调浆返回除铁工序,第二段沉钴后溶液回用作磨矿补加水,有价金属和处理后的废液都得到了资源化利用。经生产实践检验,该处理工艺具有良好的经济、环境和社会效益。

For recovering cobalt and copper from extraction raffinate of copper in a wet smelter in Congo(DRC)and realizing the cycling utilization of extraction raffinate,the process of iron removal-copper precipitation-cobalt precipitation in the first and second stages was adopted.The results show that the iron slag,the copper slag,the coarse cobalt hydroxide and the second stage cobalt slag can be obtained in this process with the calcium content of 26.79%,the copper content of 0.05%,the cobalt content of 0.12%,the loss rate of copper in the process of iron removal of 4.64%,the loss rate of cobalt in the process of iron removal of 3.14%in the iron slag;the copper content of 3.74%,the cobalt content of 2.06%in the copper slag;the cobalt content of 32.83%in the crude cobalt hydroxide;the cobalt content of 32.83%in the crude cobalt hydroxide.The total recovery rate of cobalt is greater than 95%.The iron slag can be used for building materials.The copper slag returned to the system can be used to recover copper and cobalt.The cobalt hydroxide can be sold directly.The cobalt slag in the second stage is mixed with the extraction raffinate and returned to the iron removal process.The solution after the cobalt precipitation in the second stage is reused for the replenishing water in grinding.The valuable metals and the processed solution have been recycled.After the production practice test,the treatment process has good economic,environmental and social benefits.