好氧反硝化在短程硝化反硝化工艺中的作用研究

采用SBR反应器处理垃圾渗滤液，研究了短程硝化反硝化过程中好氧反硝化的作用。结果表明，SBR反应器的亚硝化效果良好，氨氮几乎完全被氧化为NO2^- -N；该系统的活性污泥中同时存在能还原NO3^- -N和NO2^- -N的好氧反硝化菌，还原NO3^- -N的好氧反硝化菌和氨氧化菌的数量及其总活性高于NO2^- -N氧化菌，这是SBR反应器能够长期维持亚硝化状态的重要原因；有机物浓度越高则好氧反硝化速率越快，此时氨氮均被氧化为NO2^- -N，当有机物浓度达到某临界值时，好氧反硝化速率几乎保持不变；溶解氧浓度越低则好氧反硝化速率越快，释放出的OH^-会导致pH值升高。好氧反硝化对于维持和促进SBR反应器的短程硝化反硝化具有重要的作用。

Role of Aerobic Denitrification in Short-cut Nitriftcation and Denitrification Process

The SBR was used to treat landfill leachate, and the role of aerobic denitrification in short-cut nitrification and denitrification process was studied. The results show that the nitrosation efficiency in the SBR is preferable, and ammonia nitrogen is completely oxidized to NO2^- -N. The aerobic denitrifiers able to reduce NO3^- - N and NO2^- - N co-exist in the activated sludge, and the amount and total activity of the aerobic denitrifiers reducing NO3^- - N and ammonia oxidizers are higher than those of nitrite oxidizers, which is an important reason why the SBR can maintain nitrosation. The organics significantly increase the aerobic denitrification rate. Ammonia is oxidized to NO2^- - N. The aerobic denitrification rate keeps constant when the organic concentration reaches a critical value. At the lower DO levels, the aerobic denitrification rate increases, and the released OH^- can cause the rise of pH. Therefore, the aerobic denitrification plays an important role in maintaining and promoting the short-cut nitrification and denitrification.