Clean Technology 2011
M.E. Warkiani, H.Q. Gong, A.G. Fane, F. Wicaksana
Nanyang Technological University, SG
fouling, micro-fabricated membrane, micro-filtration, DOTM
Membrane pore morphology can have a significant effect on the rate of flux decline where the dominant fouling mechanism is pore blockage and cake formation. Commercial micro-filters cannot be used effectively for this purpose because they suffer from several drawbacks like tortuous pore path, rough surface, low pore density and high coefficient of variation (CV > 20%). Micro-fabricated filters, that normally made with MEMS techniques, contain pores with the same size and can thoroughly overcome these micro-structural defects. The fabrication process allows enough flexibility to control the microfilter characteristics such as pore size, pore shape and density. In this study, we employed micro-fabricated membranes to inspect the flux decline during latex and yeast cell filtration with direct observation through the membrane (DOTM) technique. The initial rate of flux decline was slower for the membrane with rectangular pores compared to the membrane with circular pores since the initial particle deposition only covered a small fraction of the rectangular holes. The obtained results provide significant insight into the effects of pore morphology and density on the membrane fouling and also demonstrate a further application of transparent micro-fabricated membranes for studying the fouling phenomenon.