反硝化细菌生物反应器去除地浸采铀矿山退役采区地下水中NO3——N的试验研究

地浸采铀矿山退役采区地下水的NO₃^--N污染是一备受关注的问题。本文通过对取自某地浸采铀矿山退役采区的污泥进行驯化，得到了能去除地浸采铀矿山退役采区污染地下水中NO₃^--N的反硝化细菌，自行设计了上流式固定床反硝化细菌生物反应器，研究了pH值、C/N比和水力停留时间（HRT）对反硝化细菌生物反应器去除地浸采铀矿山退役采区污染地下水中NO₃^--N的影响。研究结果表明：当进液pH值为6.50、NO₃^--N浓度为1 000 mg/L、HRT为2 3 h时，NO₃^--N的去除率和去除速率分别达97%和388 mg/(h•L)，生物反应器处理废水的能力达0.35 m³/(h•m³)；当进液NO₃^--N浓度为550 mg/L、HRT为1.4 h时，NO₃^--N的去除率和去除速率分别达96%和368 mg/(h•L)，生物反应器处理废水的能力达0.62 m³/(h•m³)；反硝化细菌生物反应器适宜的运行条件是pH值为5.00～8.00，C/N比为0.6～0.8。

Removal ofNO3--N From Polluted Groundwater in Decommissioned Mining Area in an In-situ Leach Uranium Mine by Denitrifying Bacteria Bioreactor

The pollution of groundwater by NO₃^- in the decommissioned mining area in an in-situ leach uranium mine is being paid more and more attention. The denitrifying bacteria by domesticating the sludge taken from the decommissioned mining area in an in-situ leach uranium mine in North West of China were obtained. An up-flow fixed-bed denitrifying bacteria bioreactor was designed. The effects of pH, the ratio of carbon to nitrogen and HRT on the removal of NO₃^--N from the polluted groundwater in the decommissioned mining area in the in-situ leach uranium mine by the denitrifying bacteria bioreactor were investigated. The results show that when pH, the concentration of NO₃^--N and HRT are set to 6.50, 1 000 mg/L and 2.3 h, respectively, the removal of the NO₃^--N amounts to 97%, the NO₃^--N degradation rate is 388 mg/(h•L) and the capacity of the bioreactor is 0.35 m³/(h•m³). When pH, the concentration of NO₃^--N and HRT are set to 6.50, 550 mg/L and 1.4 h, respectively, the removal of the NO₃^--N amounts to 96% and the capacity of the bioreactor is 0.62m³/(h•m³). The bioreactor should work on the operation conditions that pH is 5.00-8.00 and the ratio of carbon to nitrogen is 0.6-0.8.