Biofouling in Seawater Reverse Osmosis Desalination Membranes: A Review

Biofouling is one of the major problems in seawater membrane processes, especially in reverse osmosis (RO) plants. Biofouling occurs as a result of the attachment and growth of microorganisms onto the membrane. Fouling increases the pressure drop across the membrane and consequently increases the energy consumption, decreases the efficiency and shortens the life time of the RO membrane. In particular, biofouling causes a decline in water flux, an increase in salt passage and an increase in biodegradation of the membrane. There is an interest to eliminate or reduce the potential of scaling and biofouling on membranes to minimize cleaning frequency. Monitoring and control of biofouling is the most difficult issue among the other types of fouling, because microorganisms and organic matters that are responsible for biofouling behave differently under different conditions. In this review article, biofilm formation and its effective parameters, conventional and novel methods of monitoring and prevention of biofouling are investigated.