进水盐度对膜生物反应器运行效能的影响研究

进水盐度对膜生物反应器(MBR)的运行效能影响显著,尤其是进水含盐量为5 g/L时,明显恶化了污泥可滤性,膜污染速率加快;MBR混合液中溶解性微生物产物(SMP)和胞外聚合物(EPS)含量随钠离子浓度变化而变化,其中SMP中蛋白质含量与钠离子浓度密切相关;与紧密结合态EPS(TB)相比,钠离子含量对松散结合态EPS(LB)浓度的影响更大;不同盐度对COD及NH4+-N影响不明显,系统对COD及NH4+-N的去除效果稳定,分别保持在92%及94%以上,高盐度对MBR总磷去除率降低明显。

ImpactSofSsalinitySinStheSinfluentSonStheSperformanceSofSmembraneSbioreactor

The main purpose of this study was to investigate the impact of salinity in the influent on the performance of membrane bioreactor (MBR). Experimental results showed that the salinity of the feed had a obviously effect on the membrane fouling, especially to the high salinity. It was found that the salt concentration of 5g/L in the feed would deteriorate the sludge filterability, resulting in an increase the transmembrane pressure and the rate of membrane fouling. Further study found that the concentrations of soluble microbial product (SMP) and extracellular polymeric substances (EPS) in the activated sludge were closely related to the sodium ions content, especially to the protein in SMP. The concentrations of sodium ions had a more significant effect on the tightly bound EPS (TB) comparison of the loosely bound EPS (LB). It was found that the salinity had a little impact on the removal of COD and NH4 -N, the removal rate was maintained above 92% and 94%, respectively. However, a significantly decrease in the TP removal was observed under high salinity condition.