FORMATION OF DYNAMIC MEMBRANE IN SUBMERGED MEMBRANE BIOREACTORS (MBRS)

This study focused on the physicochemical and biological characteristics of sludge in submerged membrane bioreactors (MBRs), and their roles in the formation of dynamic membrane and membrane fouling. Three lab-scale submerged MBRs with SRT of 20, 40 and 60 days were performed at a constant permeate flux of 9 L/m2/h. Better permeability was achieved at longer SRT (40 and 60 days) with higher sludge concentrations because of the formation of dynamic cake layer. At of SRT 20 days, pore blocking and pore narrowing were more significant having lower sludge concentration. It was found that higher microbial concentration had better permeability, resulting in the formation of dynamic membrane. Size of particulates and colloids, and surface properties of microbial floc appeared the major parameters for the formation of dynamic membrane in the submerged MBRs.