不同电子受体生物除磷系统的运行效能对比

COMPARISON OF BIOLOGICAL PHOSPHORUS REMOVAL BETWEEN DIFFERENT SYSTEMS USING O_2 AND NO_3^- AS ELECTRON ACCEPTOR

通过平行运行2个分别以O2、NO-3为电子受体的SBR除磷系统,探讨了反硝化除磷区别于好氧除磷的工艺特征、菌群特征和污泥产率系数。通过批次试验分别考察了SBR o(厌氧/好氧)污泥和SBR n5(厌氧/缺氧)污泥吸磷特性。根据所用电子受体的不同,P O、P N、P Nn、P ON、P ONn等不同PAO被两个SBR系统筛选和富集;各系统根据自身电子受体不同而生长专一性强的PAO种类,其中P ON和P ONn等兼性PAO是SBR o系统中生物除磷的主体,P N、P Nn是SBR n5系统中生物除磷的主体;系统中兼性PAO比例越高、PAO种类越丰富,越利于除磷系统的稳定,除磷容量也越高;实验结果表明,在不同的电子受体(O2、NO-3)条件下,真实产率Y H具有显著的不同,SBR o和SBR n5的Y H分别是0.61,0.52 mg/mg,这是由于不同电子受体需要不同的微生物种群,其细胞产率不同。不过其表观产率Yobs的差异并不显著,这是由于好氧污泥的内源呼吸作用更强,有更多的污泥衰减。

By parallel operation of two phosphorus removal systems（SBR） using different electron acceptors of O2,NO3-,process characteristics and bacterial community structure and sludge yield were discussed.Being the efficient electron acceptor,NO3- or O2 supplying SBR removed phosphorus smoothly and comparatively.The phosphorus uptake of anaerobicoxic（A / O） sludge and anaerobic-anoxic（A / A） sludge were investigated via batch tests,P O,P N,P Nn,P ON and P ONn were selected and enriched in two SBR systems;strong specificity PAO types grow in each system based on the abilities of utilizing different electron acceptors.Facultative PAO of P ON and P ONn were found as the main contributors for the phosphorus removal and P N 、P Nn were found as the main contributors for the denitrifying phosphorus removal.The higher ratio they accounted in sludge,the more capacity the system possessed to remove phosphorus;The results showed that there was significant difference of real Y H at different condition for electron accepter of O2 and NO3-.And it was 0.61 and 0.52 mg / mg for SBR o and SBR n5 respectively.This was because different electrons needed different microbial population,which had different cell yield.But there was no significant difference for observed yield Y obs in SBR o and SBR n5,because the endogenesis respiration of aerobic sludge was stronger consequently more sludge being attenuated.