Effects of sludge retention time on the characteristics of mixed liquor and membrane fouling in membrane bioreactor
In the membrane bioreactor (MBR) treating municipal wastewater,the effect of sludge retention time (SRT) on the contents of the extracellular polymeric substances (EPS),tightly bound EPS (TB) and loosely bound EPS (LB) and the ratios of protein and polysaccharide in TB and LB was studied.With the extension of SRT the EPS increased and the ratios of protein and polysaccharide in TB and LB changed.The above changes influenced the charge distribution of bacterial surface,increased the proportion of hydrophilicity and hydrophobicity on the bacterial surface,changed the bacteria from the instable (R-type) to the stable (S-type),decreased the Zeta potential and increased the values of sludge volume index (SVI).The correlation analysis for the main parameters of fouling resistance was performed by SPSS software,and it was found that the correlation coefficient rp) was -0.818 for Zeta potential,0.853 for the content of suspended solids in supernatant and 0.832 for relative hydrophobicity,respectively.SRT of the MBR should be controlled below 120 times of the minimum generation-time of dominant bacteria considering the membrane fouling and sludge characteristics.
membrane bioreactor (MBR) sludge retention time (SRT) parameters of membrane fouling sludge characteristics correlation analysis
Zhanping Cao Jingli Zhang Hongwei Zhang
Key Laboratory of Hollow Fiber Membrane Material and Membrane Process of Ministry of Education,Tianj Department of Environmental and Municipal Engineering,Tianjin Institute of Urban Construction,Tianji
国际会议
哈尔滨
英文
2057-2061
2010-07-24（万方平台首次上网日期，不代表论文的发表时间）