浸出渣银浮选工艺试验研究

Experimental Study on Silver Flotation Process of Leaching Residue

某浸出渣含银140 g/t左右,铜0.61%,锌24.23%,铅2.14%,硫7.43%;银在浸出渣中的形态比较复杂,通过粒度分析知90%以上的银集中在-0.074 mm的细粒级浸出渣之中。通过分析银化学性质和浸出渣银及各物质的性质,考虑用氯化钠、硫化钠等预处理改善浮选指标;加入乙硫氮组合药剂作用来提高银浮选指标。组合用药的试验研究表明,选择组合用药制度有助于银回收率的提高。同时进行了闭路流程比较,获得了较理想工艺流程。锌浸出渣通过一粗两精三扫流程,得到了品位达到了1 860~2 060 g/t,回收率达到75.2%~79%的银精矿,铜有一定的富集,但是品位和回收率显然都不高,品位只有7%,回收率大概在43%左右。本试验研究取得了一定的成果,希望对今后类似的锌浸出渣银回收提高一定借鉴和指导。

Based on the analysis of residue of zinc leaching,the residue contained silver of 140 g/ t,copper content was about 0.61%,zinc was 24.23%,lead was 2.14%,and sulfur was 7.43%.The form of silver in the leaching residue was relative complex.After analysis of particle size,the results showed that more than 90% of the silver metal concentrated in leaching residue of-0.074 mm fines.By analyzed the chemical properties of silver and silver leaching residue,the pre-processing,such as using sodium chloride and sodium sulfide etc.the flotation index could be improved,else,Diethyl dithiocarbamate was inhibited by adding zinc ions to increase silver flotation index.Study on combined reagent system showed that combined reagent system could improve the recovery of silver.Meantime,the preferable process was obtained after comparison of closed-loop process.By adopting the process of one rough-two refined-three sweep to treat zinc leaching slag,the grade of silver concentrate achieved 1 860~2 060 g / t,and the recovery was 75.2%~79%,but though the copper concentrated too,its grade was only 7% and recovery was around 43%.Results in the paper provides certain reference and guidance to the similar work.