Modelling bioprocesses and membrane fouling in membrane bioreactor (MBR): A review towards finding an integrated model framework

The bioprocesses taking place in activated sludge wastewater treatment system itself are characterized by great complexity and yet incomplete understanding of some of the phenomena involved. The MBR technology inherent deficiencies for its simulation due to additional intrinsic complexities resulting from the interaction between concurrently occurring and dynamic biological processes with membrane filtration and the straightforward adoption of the activated sludge models’ (ASM) frameworks or their modified variations. In this backdrop, this paper compiles a brief overview of the previous developments to the current state-of-the-art mathematical modelling approaches of the MBR system. With extended discussions on particular topics such as applications of modified ASMs to MBR modelling, ASM extensions incorporating soluble microbial products (SMP)/extracellular polymeric substances (EPS) concepts, this paper also provides a guide for different end-users of mathematical models of MBR systems.

► State-of-the art in mathematical modelling studies of MBRs were summarized.
► Integrated mathematical model for MBRs and membrane fouling is yet to be developed.
► Interaction between MBR processes and membrane limit the application of ASMs to MBR.
► Empirical expressions of model parameters for calibration are essential.
► Switching functions between model variables could exclude less important parameters.