Biological-based control strategies for MBR membrane biofouling: a review

Abstract

Membrane bioreactor (MBR) technology has been paid extensive attention for wastewater treatment because of its advantages of high effluent quality and minimized occupation space and sludge production. However, the membrane fouling is always an inevitable problem, which causes high operation and maintenance costs and prevents the wide use of MBR technology. The membrane biofouling is the most complicated and has relatively slow progress among all types of fouling. In recent years, many membrane biofouling control methods have been developed. Different from the physical or chemical methods, the biological-based strategies are not only more effective for membrane biofouling control, but also milder and more environment-friendly and, therefore, have been increasingly employed. This paper mainly focuses on the mechanism, unique advantages and development of biological-based control strategies for MBR membrane biofouling such as quorum quenching, uncoupling, flocculants and so on. The paper summarizes the up-to-date development of membrane biofouling control strategies, emphasizes the advantages and promising potential of biological-based ones, and points out the direction for future studies. HIGHLIGHTS Membrane biofouling is the most complicated among all types of membrane fouling.; New physical and chemical methods may hurt membranes and environment.; Cheaper enzyme extraction methods for enzymatic control of membrane biofouling need to be introduced.; Environmental conditions and cost are the main limitations of biological strategies.; The effects of biological methods on the microbial ecology need to be explored.;

Keywords

• biofouling
• flocculants
• mbr
• quorum quenching
• uncoupling