[Effect of aeration intensity on the filterability of mixed liquor in membrane bioreactor].
The influence of aeration intensity on membrane fouling in membrane bioreactors (MBR) was to investigate. Two lab-scale MBR with aeration intensity of 500 and 100 L/h were operated for 60 days at a constant permeate flux. The dead-end filtration tests were conducted to confirm the mixed sludge filterability under each condition. The effect of aeration intensity on relative molecular mass distributions of SMP, the particle size distributions (PSD) of flocs and the quantity of extracellular polymeric substances (EPS) in MBRs were also tested. The results show that large aeration intensity has a negative influence on the filterability of mixed sludge in MBR. Further research finds that the large aeration intensity results in the increase of soluble microbial products (SMP) with a relative molecular mass (M(r)) > 10 000 in supernatant, which obviously affects the filtration of mixed sludge. It is also found that small particles in the range of 1-10 microm and the concentration of EPS in flocs remarkably increase under high aeration intensity of 500 L/h.
Zhang
Hai-Feng
HF
School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China.
Sun
Bao-Sheng
BS
Zhao
Xin-Hua
XH
Xu
Yan-Hong
YH
Qi
Geng-Shen
GS
D019149:Bioreactors; D004868:Equipment Failure; D005374:Filtration / Q000379:methods; D008567:Membranes, Artificial; D010539:Permeability; D014865:Waste Disposal, Fluid / Q000295:instrumentation* / Q000379:methods
D008567:Membranes, Artificial