n nouri - School of Chemical Engineering, College of Engineering, University of Tehran, P.O. Box ۱۱۱۵۵-۴۵۶۳, Tehran, Iran
m.r mehrnia - School of Chemical Engineering, College of Engineering, University of Tehran, P.O. Box ۱۱۱۵۵-۴۵۶۳, Tehran, Iran
r nabizadeh - Department of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences,
m.h Sarrafzadeh - School of Chemical Engineering, College of Engineering, University of Tehran, P.O. Box ۱۱۱۵۵-۴۵۶۳, Tehran, Iran

This study focused on evaluating effects of flocculant addition on performance of membrane bioreactors. A metal salt flocculant (Al2(SO4)3 ) was tested and the performance of MBR system in terms of COD and nitrate removal and membrane fouling was investigated. Addition of flocculant resulted in significant reduction of Membrane fouling. However, it had little influence on COD and nitrate removal

Membrane bioreactor (MBR), Flocculant, membrane fouling, Trans-membrane pressure (TMP)