针对高海拔地区某难处理金精矿含砷高的特点,采用细菌氧化预处理工艺,考察在一定工艺条件下,Fe,S,As脱除率及金的氰化浸出率,并对金精矿及氧化渣、氰化渣进行了分析.结果表明,Fe,S,As脱除率均达85%以上,金氰化浸出率为88.09%,说明对该类矿物采用细菌氧化预处理工艺具有可行性.机理分析表明,细菌氧化金精矿是通过直接与间接协同作用机理;氧化酸液中和主要是将液相中砷以化学性质稳定的砷酸铁沉淀除去,将重金属离子等以氢氧化物沉淀去除.
Bacterial pre-oxidation of refractory gold ore from the high altitude areas was studied. The removal rates of Fe, S, As and cyanidation leaching rate of Au were examined under the different conditions. And the gold concentrate, oxidizing slag, and leaching residue were analyzed by XRD and SEM. The results indicated that the removal rates ofFe, S and As were up to 85% and the leaching rate of gold was 88.09%. Feasibility of bio-oxidation pretreatment in the high altitude areas was proved. Based on the experimental results, the bacterial oxidation mechanism of gold concentrates and acid solution neutralization were analyzed briefly. The bacterial oxidation of gold concentrate occurred under cooperative direct and indirect mechanism. Removal of the arsenic and heavy metal ions of liquid phase in the form of ferric arsenate and hydroxide precipitation was the main purpose of acid solution neutralization.