Fouling characterization and nitrogen removal in a batch granulation membrane bioreactor

A submerged membrane bioreactor (MBR) combined with aerobic granulation reactor was investigated for the simultaneous organic/nitrogen removal and membrane fouling control. Total nitrogen (TN) removal was 59% (1.76 mg TN/g VSS h) in the aerobic granulation reactor. The filtration of granulation effluent or low operating F/M condition of the MBR could extend the filtration period of up to 78 days without any need for physical cleaning The soluble fraction was the main contributor to fouling compared to colloids and solids. The soluble polysaccharides (sPS) had more adverse effects than that of soluble protein (sPN). The deposition on a unit of the membrane's surface area was 11 mg sPS/L m2 and 8 mg sPS/L m2. As a result, the BG-MBR could be an alternative treatment process for simultaneous organic/nitrogen removal and fouling control.