污泥转移SBR工艺污泥膨胀及恢复过程中EPS的动态变化

Dynamic changes of EPS of sludge bulking and recovery in sludge shifting SBR process

采用新型脱氮除磷工艺-污泥转移SBR处理生活污水,主反应器因长时间处于低污泥负荷0.09~0.15 kg·(kg·d)^(-1),引起了丝状菌污泥膨胀;通过采取提高进水负荷及静态进水等方式,提高主反应器内的污泥负荷0.21~0.39kg·(kg·d)^(-1)使其污泥膨胀得以控制及恢复。考察在此过程中,EPS的变化对活性污泥沉降性能的影响。结果表明在污泥膨胀及恢复过程中PS/PN与SVI值呈明显正相关性,R^2分别为0.886 7、0.867 3;在污泥膨胀时EPS总量与SVI值呈正相关性;在恢复过程中,EPS总量与SVI值之间线性相关性不强。影响活性污泥沉降性能的关键因素是EPS中多糖与蛋白质的相对含量。

A new process of phosphorus and nitrogen removal and sludge-shifting SBR was used for domestic sewage treatment. Because of the long duration of the operation at the low sludge load of 0. 09 to 0. 15 kg·（ kg·d）- 1,filamentous sludge bulking was observed in the main reactor. The sludge bulking was controlled and recovered when the sludge load of the main reactor was increased from 0. 21 to 0. 39 kg·（ kg·d）- 1,by increasing the influent load and taking the way of the static water. The effects of extracellular polymeric substances（ EPS） on the settling performance of the activated sludge were also studied during the process. Positive correlations between PS/PN and the SVI value were found in both the sludge expansion and the recovery processes,with the R^2 being 0. 886 7 and 0. 867 3,respectively. The EPS amount significantly and positively correlated with the SVI value in the sludge bulking process,while the correlation between the total EPS and the SVI values was not strong in the sludge recovery process. The crucial influencing factor in the settling ability of the activated sludge was the relative content of polysaccharide and protein in EPS.