The influence of fouling resistance on the nanocomposite microfiltration process

Abstract

In order to achieve a better understanding of the fouling phenomenon, the fouling properties of two nanocomposite microfiltration membranes (poly(vinylidene-fluoride) (PVDF) and polyethersulfone (PES)) treating anaerobic baffled reactor effluent were studied. Silver nanoparticles were incorporated into the membrane surface as an anti-bacterial agent. Furthermore, the biogas produced by the anaerobic baffled reactor were applied to clean the membrane surface fulfilling the anti-biofouling approach. Fouling characteristics of both modified and unmodified membranes were investigated through the flux reduction and EPS formation measurements. The morphology of the modified and unmodified membranes surface were studied by SEM. Regarding the difficulties faced in EPS measurement, the authors proposed the resistance-in-series control as a substitute for EPS. Results showed that the gel layer (Rg) resistance progress was limited after each backwashing step while the resistance of the cake layer (Rc) decreased which is in line with extracellular polymeric substances experiment results. The highest reduction belonged to modified PVDF which was more than 49% in Rg and 78% in EPS. These findings were confirmed by the flux reduction improvement result confirming the adequacy of the employed anti-biofouling approach.