Biofouling Detection on Reverse Osmosis Membranes

Abstract

Reverse osmosis (RO) membrane technology is considered to be the premier process used for the purpose of seawater and brackish water desalination and water treatment of municipal and industrial wastewater for water reclamation and reuse. Membrane biofouling is a significant challenge in RO processes due to the interference of biofilm formed on the membrane surface on membrane performance. Thus, diverse areas of research are geared towards the understanding, prevention, and control of biofouling. Diagnosis of biofouling is difficult since no single microbial assay on the source water can accurately predict biofouling during the RO process. Biofouling evaluation methods of fouled membranes and collected biofoulants from the treatment processes are counterproductive when biofouling prevention is warranted. It is therefore important for the detection tests to be predictive enough taking into consideration the water quality characteristics of the source feed water, the properties of the RO membrane used for the water treatment, and the hydrodynamic properties during the RO process. This chapter provides an overview of biofouling tests most commonly used for detection of biofouling in the source feed water, and in the foulants and fouled membranes. It has a brief section on the use of flow cell units that can simulate hydrodynamic conditions in the RO plant with the ability to predict biofouling.