HCO_3^-浓度对厌氧氨氧化反应器脱氮效能的影响

Influence of HCO_3^- on nitrogen removal in an ANANMMOX reactor

采用序批式生物膜反应器,通过氮去除速率的测定,研究了HCO3-浓度对厌氧氨氧化反应器脱氮效能的影响.结果表明,当HCO3-与NH4+-N进水浓度比值为0.21时,反应器出水pH值大幅升高,抑制了厌氧氨氧化菌活性,使得氮去除速率大幅下降.当其比值为1.13时,反应器内pH能够降低到厌氧氨氧化菌生长所需要的环境,同时,反应器的氮去除速率开始逐步升高.当过量的HCO3-进入反应器后对厌氧氨氧化反应无影响,说明HCO3-对厌氧氨氧化反应器脱氮效能具有重要的影响,对维持反应器pH值与脱氮效能十分重要.在厌氧氨氧化反应器启动过程中HCO3-与NH4+-N进水浓度最佳比值为1.13.

The influence of the content of HCO-3 on nitrogen removal was investigated by measuring the nitrogen removal rate in an ANANMMOX reactor.The results showed that the effluent pH values increased sharply when the ratio of HCO-3 to NH＋4-N concentration was 0.21 in the influent.Correspondingly,the removal of nitrogen decreased substantially,which was attributed to the inhibition on the activity of the ANANMMOX bacteria.On the other hand,when the ratio of HCO-3 to NH＋4-N concentration was 1.13 in the influent,the effluent pH values decreased to the level favorable for the ANAMMOX bacteria.As a result,the removal of nitrogen was raised gradually.The excessive HCO-3 had little impact on the ANAMMOX reaction.This suggested that the content of HCO-3 played an important role in maintaining pH values and nitrogen removal in the reactor.The optimized ratio of the concentration of HCO-3 and NH＋4-N was 1.13 in the influent.