Membrane Fouling and the Limitations of Conventional Control in Membrane Bioreactor Wastewater Treatment: A Critical Review

This review has examined membrane fouling mechanisms and their mechanistic and data-driven modelling, together with the documented limitations of the static and proportional–integral control strategies that govern the great majority of operating MBR and conventional activated sludge plants, with particular attention to the Indian national context. The central finding is one of asymmetry rather than absence: fouling science and fouling prediction are both comparatively mature, and real-time monitoring infrastructure — particularly in the Indian decentralised treatment sector — is likewise well developed, but no reviewed study closes the loop between these capabilities and an adaptive control response. This establishes a precise, evidence-based problem statement: any advanced control architecture proposed for MBR systems must be evaluated specifically against its ability to act on fouling predictions and monitoring data that already exist, rather than against any remaining deficiency in the underlying science. The comparative evaluation of specific candidate architectures capable of closing this loop is addressed in dedicated subsequent work  

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