预浸-氰化浸出回收湿法炼锌渣中的银和金

Recovery of silver and gold in zinc hydrometallurgy residue by preleaching-cyanide leaching

某冶炼厂的锌浸出渣中银勘布粒度细,含银、金分别为381.3、1.02 g/t,可采用预浸-预浸渣氰化浸出工艺回收。重点研究了预浸条件对银、金浸出效率的影响。条件实验表明,药剂A比酸浸、氨浸具有更好的预浸效果;最佳预浸条件为药剂A浓度200 g/L、浸出液固比2:1、在50℃浸出3 h。综合条件实验得到的预浸渣渣率为66.2%,金、银的氰化浸出回收率分别为85.7%、92.9%。

The zinc leaching residue of a smelter has fine sliver particle size,and the silver and gold contents are 381.3 g/t and 1.02 g/t,respectively.They can be recovered by the preleaching-solution sulfide precipitation-cyanide leaching of pre-leaching residue-zinc powder replacement of leaching solution processes.The effects of pre-leaching conditions on leaching efficiency of silver and gold were studied.The condition experiment shows that agent A has better preleaching efficiency than acid leaching and ammonia leaching.The optimum pre leaching conditions are as follows:200 g/L of Agent A,leaching liquid-solid ratio of 2:1,leaching at 50℃for 3 hours.The pre leaching residue rate obtained from the comprehensive condition experiment is 66.2%.The leaching recovery of gold and silver is 85.7%and 92.9%,respectively.