进水负荷对A^(2)/O连续流系统运行效能及微生物中功能菌群的影响

Effect of Influent Load on Operation Efficiency of A^(2)/O Continuous Flow System and Functional Flora in Microorganisms

为深入探讨进水负荷对A^(2)/O系统的影响,本文采用A2/O连续流系统,对比研究了不同COD和磷负荷条件下系统对氮磷的去除效果,并通过检测胞外聚合物(extracellular polymeric substances,EPS)组分变化,追踪活性污泥菌群结构演替规律,揭示了不同负荷下活性污泥系统内在响应机制.结果表明:高浓度的进水COD和磷负荷更有利于优势菌群富集,该阶段优势菌属有Nitrospira、Dechloromonas和Ferruginibacter,更有利于实现更佳的脱氮除磷效果,当COD和磷负荷降低后,EPS产生菌Ferruginibacter、Terrimonas和Thauera的相对丰度明显减少,EPS的总量也减少,其中胞外聚合物中蛋白质(protein,PN)的含量增加,多糖(polysaccharide,PS)却减少.

In this experiment,the nitrogen and phosphorus removal efficiencies under different COD and phosphorus loads were studied by using A^(2)/O continuous flow system.Moreover,the bacteria structural succession of activated sludge was tracked by detecting the changes of extracellular polymeric substances(EPS)components,and the internal response mechanism of activated sludge system under different loads was revealed.The results showed that high COD and phosphorus load in influent was more conducive to the enrichment of dominant bacteria.At this stage,the dominant bacteria were Nitrospira,Dechloromonas and Ferraginibacter,which was more conducive to achieving better nitrogen and phosphorus removal effect.When the COD and phosphorus load was reduced,the relative abundance of EPS producing bacteria Ferraginibacter,Terrimonas and Thauera was significantly reduced,the total amount of EPS was also reduced,and the content of protein(PN)in extracellular polymer increased,Polysaccharide(PS)decreased.