胞外聚合物EPS在废水生物除磷中的作用

对EPS在废水生物除磷中的作用机理进行系统研究,探讨和完善生物除磷机理.试验结果表明,在生物除磷系统中,EPS贮存了部分磷,在生物除磷中起着重要的作用.在厌氧.好氧交替过程中.EPS中磷含量呈厌氧减少、好氧增加的周期性变化;污泥中的磷有82%左右被聚磷菌吸收,另外18%左右的磷聚集在EPS中;一个运行周期中基质所减少的磷84.3%被聚磷菌过量吸收,15.7%被贮存于EPS中;EPS对磷的去除能力与EPS的含量正相关.此外,泥龄对EPS影响较大,对EPS在生物除磷中的作用影响显著,泥龄越长,EPS含量越高,EPS中所贮存的磷含量越高.而磷负荷对EPS除磷影响不显著.

Study on the action of extracellular polymeric substances (EPS) in biological phosphorus removal from wastewater

The mechanisms of biological removal of phosphorus are discussed and the influence of extracellular polymeric substances (EPS) is investigated. EPS plays an important role in phosphorus removal by storing phosphorus. During an alternating anaerobic-aerobic process, a periodic variation was observed. The phosphorus content increased under aerobic conditions but decreased under the anaerobic conditions. Approximately 82% of P in the sludge was absorbed by the poly-phosphate accumulating organisms (PAOs) and the remaining 18% were enriched in the EPS. During a cycle, approximately 84.3% of the reduced phosphorus in the substrate was absorbed by the PAOs while 15.7% of it was stored in the EPS. The removal of phosphorus by EPS was positively correlated with the EPS content. The sludge retention time (SRT) affected the content of EPS and hence its phosphorus removal ability. Higher SRT resulted in higher EPS and higher phosphorus content. Phosphorus loads showed marginal impact on phosphorus removal.