Rethinking Biofilm Engineering and Fouling Resistance in Membrane Bioreactors

Membrane bioreactors (MBRs) are increasingly recognized as a key technology in sustainable wastewater treatment, offering a high effluent quality through the integration of biological degradation and membrane filtration. Among the critical factors influencing their performance are biofilm dynamics and membrane fouling. This article critically examines recent advances in biofilm engineering and antifouling strategies for MBRs, with an emphasis on microbial community modulation, quorum quenching, and hydrodynamic control to improve biofilm stability. In parallel, the review examines material-based and biological methods to mitigate membrane fouling, emphasizing multifunctional surfaces and emerging biocontrol strategies. Key operational challenges, such as energy consumption, cleaning frequency, and membrane aging, are evaluated alongside future research directions in materials design, microbial ecology, and real-time system optimization. The integration of these innovations is essential for advancing MBR technologies that are robust, resource-efficient, and aligned with circular economy principles.