过量曝气对生物除磷性能的影响研究

Effect of Excessive Aeration on Biological Phosphorus Removal

采用两组A/A/O方式运行的SBR反应器,溶解氧分别控制在2～4mg/L(对照组)和6～8mg/L(过量曝气组),通过试验对比研究了过量曝气对聚磷菌厌氧释磷、缺氧吸磷、好氧吸磷性能的影响。结果表明:过量曝气初期,出水磷浓度低于对照组,一周后出水磷浓度开始上升,除磷率下降了18%;过量曝气时,厌氧释磷量是对照组的1.45倍,释磷速率不变,缺氧吸磷量增加,但反硝化聚磷菌的比例减少,好氧吸磷量和吸磷速率均降低,分别为对照组的75%和68%,而内源损耗引起的无效释磷和好氧吸磷能力降低是除磷效果变差的主要原因;过量曝气使污泥的SVI值升高,平均粒径减小,出水SS略优于对照组,污泥的含磷量降低,总磷去除效果变差,长期过量曝气,将会导致生物除磷过程的恶化。

This paper adopts two parallel SBRs（the dissolved oxygen is respectively 24 mg/L and 68 mg/L） running with anaerobic/anoxic/aerobic behaviors to research the effect of excessive aeration on bio logical phosphorus removal. Results show that, in the early excessive aeration, the phosphorus concentra tion in effluents is lower than that in the control group, and one week later the phosphorus removal decrea ses by 18% ;in the condition of excessive aeration,the amount of phosphorus release is 1.45 times of that in the control group while the release rate is the same,and the amount of anoxic phosphorus uptake increases while the ratio of DPB decreases;the amount of aerobic phosphorus uptake is only 75% of that in the con trol group,and the uptake rate also decreases to 68%of that in the control group;the main reason for the deterioration of the phosphorus removal is the invalid increased phosphorus release and the decrease of aer obic phosphorus uptake capacity caused by endogenous losses;SVI increases, particle diameter is smaller,