(430d) Microbial Adhesion to Advanced Water Treatment Membrane Materials: Implications for Biofouling

Kirschling, T. L., National Institute of Standards and Technology
Greenlee, L. F., National Institute of Standards & Technology

Membrane based water purification will be essential for providing potable water from saltwater and wastewater as global water scarcity becomes more pressing. One of the biggest challenges to membrane based water treatment processes is biofouling which causes significant increases in transmembrane pressure drop and decreases in flux. This performance decline increases both energy requirements and the number of required cleaning cycles leading to significant cost increases. Novel process improvements and advanced materials have the potential to decrease biofouling, but an understanding of how these factors impact membrane associated microbial communities and their interactions with the underlying material is lacking. This study characterizes the microbial foulants recovered from a reverse osmosis (RO) pilot plant undergoing a six month study to assess the use of ozone pretreatment prior to the RO train. Pyrosequencing of the 16S rDNA gene was used to determine which microbial strains were prevalent in the biofoulant material. Sequencing data was compared with isolated bacterial strains from the membrane surfaces. Species of the genus Mycobacterium were found to be dominant in both ozonated and control trains. The adhesive properties of relevant isolates were studied along with their adhesion to various polymer films using atomic force microscopy (AFM) and quartz crystal microbalance (QCM) methods. The results of these studies with a Mycobacterium sp. isolate will be discussed.