微生物群落修复酸法地浸采铀矿山退役采区地下水

Remediation of groundwater in decommissioned mining area of acid in-situ leaching uranium mine by microbial community

通过添加乙醇激活并富集出富含还原功能微生物群落的沉积物,再将该沉积物添加至新疆酸法地浸采铀矿山退役采区地下水−岩芯样微模型中,监测了pH值、铀、硝酸根、硫酸根、微生物群落结构、铀的价态、结合形态等参数的变化。结果表明:微模型中地下水的pH值在15 d时升高至5.5,铀和硝酸根的浓度分别降至0.039和16.17 mg/L;60 d时地下水的硫酸根浓度降至107.31 mg/L,均达到了相关国家排放标准。60 d时,地下水−岩芯样微模型中可还原U(Ⅵ)的功能微生物丰度高达75%,地下水中2/3的U(Ⅵ)被微生物群落还原为U(Ⅳ);在微生物群落的作用下,40.35%不稳定结合形态的铀转化为稳定结合形态的铀。

The reduction-functional microbial community in the sediment was activated and enriched by adding ethanol,and then the sediment was added to the groundwater-core sample microcosms obtained from the decommissioned mining area of an acid in-situ leaching uranium mine in Xinjiang.The changes of pH,concentrations of uranium,nitrate and sulfate,microbial community structure,and valence and binding morphology of uranium were detected.The results show that pH of groundwater in microcosms reaches 5.5 at the 15th day of incubation,and the concentrations of uranium and nitrate decrease to 0.039 and 16.17 mg/L,respectively.The sulfate concentration decreases to 107.31 mg/L at the 60th day of incubation.All these indexes of groundwater meat the relevant national discharge standards.The abundance of functional microbial community that can reduce U(Ⅵ)in the groundwater-core sample microcosms is as high as 75%at the 60th day of incubation.Meanwhile,the functional microbial community has reduced 2/3 of U(Ⅵ)in the groundwater to U(Ⅳ),and 40.35%of uranium is converted from unstable forms to stable forms.