محسن اكبرزاده

Membrane bioreactors represent cutting-edge wastewater treatment technologies, yet they consistently grapple with a persistent challenge: membrane fouling. To address this issue, innovative membrane surface modification techniques emerge as a beacon of hope, offering potent solutions to diminish fouling and enhance membrane bioreactor performance. The objective of this research is to engineer an ideal surface pattern that can give rise to a patterned polymer membrane, thus amplifying the efficiency of the membrane within the bioreactor system. In pursuit of this goal, the initial step involved simulating an activated sludge filtration system within the computational fluid dynamics framework. The aim was to scrutinize the impact of various surface patterns on patterned membrane fouling. The simulation outcomes unveiled that all the examined designs outperformed the flat membrane in terms of fouling reduction. Among the 38 designs analyzed, the "triangle-big triangle" design demonstrated the highest resistance to fouling. Subsequently, a "triangle-big triangle" patterned casting knife was designed and fabricated based on the simulation results. Patterned polymer membranes were synthesized using the fabricated casting knife and Spray-modified non-solvent induced phase separation (S-NIPS) method. The optimal concentration for synthesizing a patterned membrane with the desired pattern fidelity was determined by altering the poreformer concentration. In order to scrutinize and compare the membrane's performance in the membrane bioreactor system field emission scanning electron microscopy analyses, contact angle analyses, pure water flux measurements, fouling resistance, and protein rejection test were carried out. In the structural eva‎luation phase, the introduction of surface patterns and the application of the S-NIPS transformed the membrane's pore structure significantly compared to the reference flat membrane. Consequently, the active surface and porosity of the optimized patterned membrane surged by 41% and 18%, respectively, in comparison to the flat membrane. This translates to a boost from 9 cm² to 12.72 cm² in active surface and an increase of 50% to 68% in porosity. Despite these substantial improvements, the protein rejection rate was only reduced by slightly under 2% in contrast to the flat membrane. Meanwhile, pure water flux experienced a remarkable 179% increase. In terms of fouling eva‎luation, the implementation of surface patterns led to a noteworthy enhancement in fouling resistance. This improvement resulted in an impressive surge in the flux recovery ratio, climbing from 62% for the flat membrane to a remarkable 94% for the optimal patterned membrane. These results underscore the patterned membrane's exceptional potential to elevate the efficiency and bolster the performance of membrane bioreactors.

بيوراكتورغشايي , غشا پليمري طرحدار , شبيه سازي بيوراكتورغشايي , گرفتگي غشا

membrane bioreactor , patterned polymeric membrane , membrane bioreactor simulation , membrane fouling

Mohsen Akbarzade

Dr. Tooraj Mohammadi