Filtration Characteristics of Charged Alumina Membranes for Methanogenic Waste

For the purpose of selecting or developing appropriate inorganic membranes for methane fermentation membrane bioreactors, the relationship between surface charge of the inorganic membrane and filtration characteristics of methanogenic waste was examined. The zeta potential of alumina membranes with 0.5 μm pores was controlled to negative, zero and positive, respectively, in the methanogenic waste by surface treatment. Cross-flow filtration experiments showed that negatively charged alumina membranes had twice the filtration flux of positively charged membranes when waste was fed to the membrane at 3.0 m·s–1. And it was found that the influence of membrane charge on filtration flux resulted from the influence of membrane charge on the hydraulic resistance of Rp, which was attributed to the plugging of suspended particles in the feed during filtration.