Qualitative analysis and simulations of the biological fouling problem on filtration membranes

The mitigation of fouling formation and development in filtration systems represents the most critical aspect for water treatment, as it naturally affects both the operational costs for management procedures, and the duration of filtration devices. As it constitutes an artificial physical barrier for solid particles retention, membrane systems are perfect environments for the adhesion and development of biological fouling layers, especially in wastewater treatment reactors. Based on recent results, the present work focuses on the qualitative analysis of a mono dimensional continuous model for biofouling dynamics in microfiltration systems. The free boundary problem accounting for the evolution of the biofouling layer during the filtration regimen has been discussed in terms of existence and uniqueness of the solution. The achieved results represent a consistent base for numerical studies related to the correct prediction of transmembrane pressure in membrane systems. Numerical examples related to the heterotrophic-autotrophic interaction occurring in wastewater treatment plants have been presented to highlight the effect of crucial biological aspects, such as extracellular polymeric substances (EPS) accumulation, usually neglected in the classical membrane filtration modeling. The description of biofouling dynamics and membrane performance during the filtration regimen highlight key aspects for microfiltration system management in all industrial applications.