A review of the current in-situ fouling control strategies in MBR: Biological versus physicochemical

Fouling in membrane bioreactors (MBR) is a bottleneck problem limiting their application. In-situ fouling control strategies have been continuously developed for decades, and can be mainly categorized as biological and physicochemical approaches. However, the mechanisms and performance of these methods as well as their application prospects have not been thoroughly discussed and compared in a systematic manner. This study was aimed at providing a detailed review on the various in-situ biological and physicochemical methods in terms of fouling control performance, fouling reduction mechanisms and practicability. This involves a comparison of the popular biological control strategies including quorum quenching (QQ)) and physicochemical approaches such as NaClO backflushing, hybrid electrochemical MBR and anti-biofouling membrane development, with the analysis of their potential, existing issues and practicality in full-scale applications. Future work is also recommended for developing more sustainable and more widely applicable MBR fouling control strategies.