Review about modifications of antifouling polymer membranes in anaerobic membrane bioreactors (AnMBRs) wastewater treatment

Biofouling is a problem that decrease the wastewater treatment capacity of the anaerobic membrane bioreactors (AnMBR), which is the process combine activated sludge and membrane filtration. In order to resolve it, different modification techniques are applied and studied in AnMBR to decrease biofouling via convert hydrophobicity to hydrophilicity of the membrane surface and enhance the permeability. In this study, a summary of recent advancements in the modification of polymeric membranes for antifouling in anaerobic membrane bioreactors (AnMBRs) wastewater treatment is provided. Plasma technology, UV irradiation and coating are used to introduce flexible radicals as well as functional groups like hydroxyl and carbonxyl groups, resulting in appropriate hydrophilicity. Blending appealing additives into the casting solution, such as hydrophilic monomers and nanomaterials, is another way to increase wetting permeability and to reduce the antibacterial adhesion. Furthermore, layer-by-layer modification is another potential sustainable approach since no chemicals, such solvents or pore formers, are used. Modified AnMBR are suitable for biofouling reduction up to 90 %, the an extraordinary finding is self-cleaning of modified membrane with more than 50 % of reversible flux. Future study should focus not only to the enhance of biofouling properties but also the stabilities of the polymer membranes.