Fouling characteristics of a membrane bioreactor and nanofiltration hybrid system for municipal wastewater reclamation

► Large amounts of polysaccharides with small MW are produced by the MBR. ► Polysaccharide-like substances show a fluorescence peak at Ex = 230 nm/Em = 420 nm. ► Hydrophobic and hydrophilic fractions are responsible for fouling of the MBR. ► Polysaccharide-like substances are found for as major foulants of the NF membranes. ► Membrane properties provide a strong effect on flux decline of the NF membranes.