Fouling of Membrane Bioreactor in Wastewater Treatment

Despite significant advantages offered by membrane bioreactors (MBR) over activated sludge systems in wastewater treatment, membrane fouling and associated high operating costs necessary for control or preventive measurements, remain the greatest obstacle for commercialization of this treatment system. Hydrodynamic conditions, concentrations of soluble microbial products (SMP), and extracellular polymeric substances (EPS), have found to play major roles in membrane fouling, since a linear relationship between fouling rate and polysaccharide concentration in the sludge supernatant was observed. Considering the volume of investment in the rapid growth of wastewater treatment plants envisaged for the Iranian cities by the more traditional activated sludge system, latest advancement in MBR technology should be kept under scrutiny. In this article, the importance of SMP, EPS and hydrodynamic conditions in membrane fouling have been discussed and the latest advanced control procedures including feedback control, addition of flux enhancers and nanomaterials, optimized hydrodynamics and inhibition of quorum sensing are explained

Keywords:

Membrane bioreactor technology , Membrane fouling , Extracellular polymeric substances , Soluble microbial products