SRT对MBR污泥性质的影响

以浸没式膜-生物反应器(SMBR)处理模拟赖氨酸废水为研究体系,考察SRT在10、20和40 d条件下,SMBR中的胞外聚合物(EPS)组分和含量、污泥沉降性能和污泥相对疏水性等污泥性质的变化及其对膜污染的影响。结果表明,随着SRT的延长,混合液中EPS总量呈递减趋势,TBEPS中蛋白质与多糖的比值呈上升趋势,污泥的沉降性能变差,相对疏水性增强;膜通量下降速率变大,膜污染加重。污泥性质与膜污染的相关性表明,膜污染与蛋白质和多糖的比值、污泥沉降性能和相对疏水性呈正相关关系,而与EPS呈负相关关系。

Effects of sludge retention time on sludge characteristics in membrane bioreactors

The variations in sludge characteristics,such as components and contents of extracellular polymeric substances(EPS),sludge settle ability and relative hydrophobic,and its impacts on membrane fouling,were investigated at sludge retention times(SRTs) of 10 d,20 d and 40 d in a submerged membrane bioreactor(SMBR)treating synthesis lysine wastewater.The results showed that,as the SRT increased,the concentration of EPS decreased,and the ratio between protein and polysaccharide in tightly bound EPS(TBEPS) increased.The settling ability of sludge became worse,while the relatively hydrophobic raised with the increase of SRT.The results of correlation analyses between sludge properties and membrane fouling indicated that the ratio of protein to polysaccharide,sludge settling ability and relative hydrophobic had strong positive correlations with membrane fouling,while the EPS had a negative impact on membrane fouling.