预浸出对高杂质硫化铜精矿杂质脱除的影响

Effect of pre-leaching on impurity removal of high impurity copper sulfide concentrate

针对采用硫酸化焙烧—浸出—直接电积工艺处理高杂质硫化铜精矿时,杂质含量高,不能满足电积工艺要求的问题,通过在该工艺之前增加预浸出工序,预先脱除精矿中的部分主要杂质,避免或减少杂质对后续工序的影响。采用正交试验法研究了预浸过程中酸矿比、温度、时间和液固比对杂质Cu、Co、Fe、Mn浸出率的影响。在此基础上,采用单因素试验法进一步优化了工艺参数条件。结果表明,增加预浸出可以使焙砂浸出液中影响铜电积的主要杂质元素Fe、Mn、Co等含量降低,铜的整体浸出率增加;预浸出过程酸矿比对杂质元素浸出率的影响最大;较优预浸出工艺条件为:酸矿比0.4∶1、温度50℃、时间2h、液固比3∶1时,Cu的最终浸出率超过99%,焙砂浸出液中Fe、Mn含量分别为0.15g/L和0.005g/L。

In view of the problem that the content of impurities in high impurity copper sulfide concentrate cannot meet the requirements of electrowinning process when sulfuric acid roasting leaching direct electrowinning process is adopted,some main impurities in the concentrate are removed in advance by adding pre-leaching process before the process,so as to avoid or reduce the influence of impurities on the subsequent process.The effects of acid ore ratio,temperature,time and liquid solid ratio on the leaching rate of impurities Cu,Co,Fe and Mn were studied by orthogonal test.On this basis,the single factor test method was used to further optimize the process parameters.The results showed that with the increase of pre-leaching,the contents of main impurity elements such as Fe, Mn,Co,which affect copper electrowinning in calcine leaching solution can be reduced,and the overall leaching rate of copper can be increased;the acid ore ratio has the greatest influence on the leaching rate of impurity elements in the preleaching process.The optimum pre-leaching conditions are as follows:acid ore ratio 0.4∶1,temperature50 ℃,time 2 h,liquid solid ratio 3∶1,the final leaching rate of Cu is more than 99%,and the contents of Fe and Mn in calcine leaching solution are 0.15 g/L and 0.005 g/L,respectively.