抛刀岭难处理金精矿细菌氧化-提金实验研究

抛刀岭金矿是典型的含砷难处理金矿，针对其金精矿，结合矿石特性，考察了细菌氧化预处理效果。实验结果表明：对于含金 20.30 g/t、含砷3.39%、含硫29.8%及含铁4.10%的抛刀岭金精矿，直接氰化浸出金的浸出率仅为30%。矿石中的主要金属矿物为黄铁矿、毒砂和雄黄；脉石矿物有长石、方解石、石英和绢云母等，属于难浸金矿石。该金精矿经HQ0211菌氧化预处理8 d后，脱砷率达到46.25%，细菌氧化渣金含量达32.1 g/t，失重率为42.53%。细菌氧化渣在通气情况下进行氰化提金，NaCN浓度为0.1%、pH值为10.5~11，48 h后氰化结束，氰化渣质量由原来的300 g减少为290 g，渣率为96.67%，氰化渣中金含量从32.1 g/t降低至2.7 g/t，金的浸出率达到91.59%，氰化过程中NaCN消耗量为13.53 kg/t。HQ0211菌氧化预处理氰化提金效果显著，为该矿处理工艺提供了可靠数据，并为此类矿石的有效利用提供了参考。

Experimental Study on Bacterial Oxidation-Gold Extraction of Paodaoling Refractory Gold Concentrate

Paodaoling gold mine is a typical arsenic-bearing refractory gold deposit，for its gold concentrate，combined with ore properties，the effect of biooxidation pretreatment was investigated.The experiment results showed that this kind of gold ore contains 20.30 g/t gold，3.39% arsenic，29.8% sulfur and 4.10% iron，and a 30% leaching rate of the gold concentrate can be obtained by direct cyanidation.The main metallic minerals in the gold ore are pyrite，arsenopyrite and realgar.The gangue minerals include feldspar，calcite，quartz，sericite and so on，and it belongs to the refractory gold ore.After 8 days of biooxidation process by HQ0211 bactreium，the arsenic removal rate was 46.25%.The oxidation residue contains 32.1 g/t gold and the weightloss rate was 42.53%.The gold cyanidation process of oxidation residue was conducted under ventilation conditions.The sodium cyanide was 0.1% and pH was 10.5~11.After cyaniding for 48 hours，the weight of gold ore was reduced from 300 g to 290 g，and the residue yield was 96.67%.According to the analysis results of cyanidation residue，the gold content reduced from 32.1 g/t to 2.7 g/t and the gold leaching rate was 91.59%，which was greatly improved.The consumption of sodium cyanide in cyanidation process was 13.53 kg/t.The gold cyanidation effect of Paodaoling gold mine was remarkable after pretreatment by HQ0211 bacterium，it provide reliable data for treatment process of this gold ore and provide reference for effective utilization of this kind of mineral.