Contribution of extracellular polymeric substances (EPS) to the sludge aggregation.
The contribution of extracellular polymeric substances (EPS), including loosely bound EPS (LB-EPS) and tightly bound EPS (TB-EPS), to the aggregation of both aerobic and anaerobic sludge is explored using the extended DLVO theory. It is observed that the aggregation abilities of both sludge samples decrease with the extraction of LB-EPS and TB-EPS, implying the crucial roles of EPS in sludge aggregation. Furthermore, through analyzing the interaction energy curves of sludge before and after the EPS extraction using the extended DLVO theory, it is found that both LB-EPS and TB-EPS have a substantial contribution to the sludge aggregation. The interaction energy of LB-EPS is always negative, suggesting that the LB-EPS always display a positive effect on the sludge aggregation. On the other hand, the interaction energy of TB-EPS is not always negative, depending on the separation distance between sludge cells. These results imply that the LB-EPS and TB-EPS have different contributions to the sludge aggregation.
Liu
Xiao-Meng
XM
Department of Chemistry, University of Science & Technology of China, Hefei, 230026 China.
Sheng
Guo-Ping
GP
Luo
Hong-Wei
HW
Zhang
Feng
F
Yuan
Shi-Jie
SJ
Xu
Juan
J
Zeng
Raymond J
RJ
Wu
Jian-Guang
JG
Yu
Han-Qing
HQ
D000693:Anaerobiosis; D002681:China; D011108:Polymers; D012722:Sewage
D011108:Polymers; D012722:Sewage