针对含硫砷含碳金精矿的性质,进行了提金工艺探索。该金精矿经直接氰化浸出,金浸出率仅为1.33%;经两段焙烧—氰化浸出,金浸出率提高到71.33%,但该方法所需时间长、能耗高、有害元素的脱除不完全且容易发生过焙烧。鉴于此,提出了一段富氧添加硫酸钠焙烧—硫化钠碱浸强化—焙砂氰化浸出提金工艺。一段富氧添加硫酸钠焙烧不但可强化硫、砷和碳的脱除,降低焙烧温度50℃,缩短焙烧时间至30 min以内,而且少量硫酸钠的添加可消除焙砂的固结问题,使金的浸出率增加到84.14%;而对焙砂再进行硫化钠碱浸处理,不仅使被包裹的金得到进一步解离,金浸出率提高到94.72%,且可以回收锑,实现金矿资源的综合回收利用。
According to the property of carbonaceous gold concentrates containing sulfur and arsenic,the paper carried out experimental research on gold extraction. Gold extraction only reaches 1. 33 % by direct cyanidation leaching. Gold recovery increases to 71. 33 % by two-stage roasting pretreatment,but the method has the disadvantages of long processing time,high energy consumption,incomplete removal of detrimental elements and incidental over-roasting. In light of that,the paper proposed that the ores be treated by one-stage oxygen-rich roasting with sodium sulfate additive and the calcine be leached by cyanidation after intensified by alkaline leaching by sodium sulfide. One-stage oxygen-rich roasting with addition of sodium sulfate not only intensifies the removal of sulfur,arsenic and carbon,cools the roasting temperature by 50 ℃,shortens time to less than 30 minutes,but solves the consolidation problem of calcines by adding a small amount of sodium sulfate,eventually increasing Au extraction to 84. 14 %. After the calcine was subjected to alkaline leaching by sodium sulfide,the encapsulated gold got effectively liberated and the Au recovery was elevated to 94. 72 %. Also,antimony could be recovered and comprehensive recovery of gold ore resource was realized.