晚期垃圾渗滤液实现短程硝化影响因素分析

Factors effecting shortcut nitrification for treatment of advanced stage landfill leachate

利用SBR反应器，探讨了溶解氧（DO）、温度和pH值对晚期垃圾渗滤液实现短程硝化的影响．结果表明：DO质量浓度为0．75mg／L左右时，短程硝化效率较高，大于该值时硝化类型有向全程硝化转变的趋势，低于该值时最大氯氧化速率下降较大；当DO质量浓度保持在0．75mg／L左右时，降低温度和pH值，最大氨氧化速率下降，但亚硝氮积累率仍保持在较高水平．低溶解氧情况下，由于DO的抑制作用，硝酸菌没有表现出较亚硝酸菌更适应较低温度或pH值环境的特性，DO是实现晚期垃圾渗滤液短程硝化的控制因素．当DO为0．75mg／L左右，pH值为6．5～8．0，温度为25～27℃时，可以达到96％以上的氨氮去除率及98％以上的亚硝氮积累率，在此条件下最大氨氧化速率为0．097-0．12s／（gVss·d）．

The effects of dissolved oxygen concentration, temperature and pH on the nitritation for the treatment of advanced stage landfill leachate was studied, in a sequencing batch reactor. The results showed that the higher efficiency of nitritation was obtained at a DO of 0.75 mg/L and the type of nitrification can be gradually converted into complete nitrification at a DO of above 0.75 mg/L. Once DO concentration was below 0.75mg/L, the maximum rate of ammonia oxidation significantly decreased. However, when DO concentration was about 0.75mg/L, the maximum ammonia oxidation rate decreased and higher nitrite accumulation rate was still achieved at lower temperature and pH levels. It can be concluded that dissolved oxygen was the key factor in achieving nitritation because activity of nitrobacteria was inhibited by lower DO under lower temperature and pH levels. About 96% of ammonia removal rate and over 98% of nitritation rate could achieved while the maximum ammonia rate reached 0.097-0.12 g/（gVss·d）at DO of about 0.75 mg/L, pH of 6. 5-8.0 and temperature of 25-31℃.