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为了确定加工过程中砷的最终结果，评价生物予处理对金提取的影响，研究了难处理合砷金矿石的生物氧化。试验是在半－间歇搅拌生物反应器、连续流搅拌生物反应器和巨柱式生物浸出系统中，使用铁和硫化物联合氧化细菌进行的。监测了生物氧化过程中硫化物的氧化和砷的溶解作用，并将其结果与随后进行的氰化试验过程中的贵金属的提取联系起来。另外，采用阴离子高效液相色谱／原子吸收光谱技术监测了存在于溶液中的亚砷酸盐［Ａｓ（Ⅲ）］和砷酸盐［Ａｓ（Ｖ）］浓度随时间的变化；还评价了最终尾矿和中和生物氧化溶液所得到的含砷矿泥的稳定性。浸出结果表明，使用生物氧化工艺从这种矿石中可获得９５％以上硫化物氧化率和４７％的砷提取率。在生物予处理后的氰化过程中金的提取率由４９％增加到约８０％。溶液中砷的总浓度高达１７ｇ／Ｌ对细菌数目并无明显的不利影响。在所有情况下，砷最初以Ａｓ（Ⅲ）形式溶解。典型的浸出液里Ａｓ（Ⅲ）的含量是Ａｓ（Ⅴ）的１８倍。由于Ａｓ（Ⅲ）化合物比Ａｓ（Ⅴ）化合物稳定性差且毒性大得多，因此矿泥物料在环境中的长期稳定性是至关重要的。本文将对矿泥毒性浸出过程稳定性试验结果加以论述。
In order to determine the final result of arsenic during processing and evaluate the effect of biological pretreatment on gold extraction, the biooxidation of refractory arsenic gold ores was studied. The experiments were carried out in the combination of semi-batch stirred bioreactors, continuous-flow stirred bioreactors and giant column bioleaching systems using iron and sulphide combined with oxidizing bacteria. The oxidation of the sulphides and the dissolution of arsenic during the biooxidation were monitored and the results were linked to the subsequent extraction of precious metals during the cyanidation test. In addition, the concentration of arsenite [As (III)] and arsenate [As (V)] in solution was monitored over time using anion-exchange high performance liquid chromatography / atomic absorption spectroscopy; Tailings and the stability of arsenic-containing slimes obtained by neutralizing biological oxidation solutions. Leaching results showed that more than 95% sulfide oxidation and 47% arsenic extraction were obtained from this ore using a biooxidation process. The gold extraction rate increased from 49% to about 80% during the biological cyanide pretreatment. The total arsenic concentration in the solution was as high as 17 g / L with no significant adverse effect on the number of bacteria. In all cases, arsenic initially dissolves as As (III). The As (Ⅲ) content in typical leachate is 18 times higher than that of As (Ⅴ). Since As (III) compounds are less stable and more toxic than As (V) compounds, the long-term stability of the slime material in the environment is of crucial importance. In this paper, the results of the stability test of leaching toxicity of slime are discussed.