Chemically enhanced backwashing for NOM removal of ceramic ultrafiltration membranes using conventional cleaning chemicals with a surfactant

Abstract

Membrane filtration has developed into a robust water treatment step. However, limited research has been conducted on new membrane cleaning solutions. Conventional membrane cleaners such as NaOCl are known to form DBPs with organic matter and damage polymeric membranes at high concentrations. Our research examines the use of surfactant (SDS) in combination with conventional membrane cleaners (NaOCl and NaOH) to clean a ceramic UF membrane as chemically enhanced backwash (CEB). Existing research primarily looked at the combination of surfactants with NaOH for long duration cleaning. Limited research has also been conducted on the combination of surfactants with high NaOCl concentrations. Initial tests showed the addition of SDS significantly reduced the surface tension of various CEB solutions. Subsequent fouling and cleaning studies demonstrated better cleaning efficiency when CEB contained SDS. In general, the addition of SDS provided some improvement to backwash fouling control although more research is needed in this area. iii Acknowledgement Firstly, I would like to thank my supervisor, Dr. Onita D. Basu for giving me the opportunity to do this research project. This research experience helped me learn more about myself. Dr. Basu was very supportive during my time as a research student and was always available when I needed help. My sincere appreciation also goes to my research group members, Daanish Singh and Andrea Ninabanda for their ideas and support with my research experiments. I am also grateful to have the support of the rest of the Basu research group. I would like to thank NSERC and the Kochar family scholarship for funding this research.Finally, I would like to thank my parents, Ninan and Renu as well as my sister Susan, for their never-ending love and support when the going was tough.