矿浆电解法浸出多金属硫化矿中银的工艺条件探讨

Leaching conditions of silver from polymetal sulphide ore using slurry electrolysis

在研究矿浆电解法浸出广西某大型含银多金属硫化矿中银的浸出速率变化规律基础上，根据国内外文献资料，总结出银的浸出率与矿粉中银的赋存形式的关系。银在银黝铜矿和在难分解的黄铁矿中的分配率是决定矿粉磨细粒径、电解面积电流、电解时间的最重要因素．在分配率很低时，可采取低电流密度电解，如100～150A／m^2，银的浸出率≥95％；在分配率较高时，采用低电流密度电解，因银黝铜矿及黄铁矿中的银难以浸出，所以银浸出率较低；在分配率小于≤10％时，可采用中等电流密度300～400A／m^2，同时矿粉的磨细程度要保证银矿物晶体部分或全部暴露在黄铁矿晶粒表面，适当增加电解时间，银的浸出率可超过90％．

Based on the change rule of leaching velocity of silver from polymetal sulphide ore with slurry electrolysis in a large silver-containing polymetal sulphide mine of Guangxi and reported data, the relation between the leaching rate of silver and the occurrence of silver in ore pulp is concluded. The distribution ratio of silver in aftonite and pyrite is the most important factor to determine granularity, current density and electrolytic time. When the distribution ratio is low, low electrical current density, such as 100 - 150 A/m^2 , can be used in slurry electrolysis and the leaching rate is higher than 95 % ; when low electrical current density is chosen on the occasion of the higher distribution ratio, the leaching of silver from aftonite and pyrite is difficult and the leaching rate is low; when the distribution ratio is lower than 10%, a moderate current density （300 -400 A/m^2） can be used in slurry electrolysis. At the same time, the silver-containing mineral crystal is to expose on the surface of pyrite particles and the electrolytic time should be increased properly. Under these conditions, the leaching rate of silver can be higher than 90%.