Influence of hydrophobic and electrostatic membrane surface properties on biofouling in a submerged membrane bioreactor under different filtration modes

This study investigated the effect of membrane surface properties on membrane biofouling in a submerged membrane bioreactor treating synthetic wastewater, by employing qualitative membrane surface examination techniques and biofilm quantification. The investigation was carried out on three different types of fouled membrane samples obtained using different filtration methods. Lipid phosphate concentration, which represents viable biomass, was employed as a direct measure of biofouling. Contact angle and zeta potential measurements of clean and fouled ultrafiltration and hollow fibre membranes were conducted. Zeta potentials of membrane samples were measured at various electrolyte pHs. The surface energy of membrane samples was calculated and reported from the data obtained from contact angle of measurements. The outcomes from this study can be used as the basis of a technique to examine the potential of biofouling in membrane processes.