抄録
The characteristics of the cross-flow filtration of polymer suspensions, municipal wastewater and activated sludge were investigated using microfiltration membranes and ultrafiltration membranes. The flux decline was explained by a gel-layer model in which scouring effect at membrane surface was considered. Physical meanings of the parameters in this model were examined by experiments on various conditions. The observed specific filtration resistance implied that the gel-layer consisted of smaller particles than those in the bulk of municipal wastewater and mixed liquor of activated sludge. By adding polymer particles to the activated sludge steadystate flux was not increased but the rate of flux decline was decreased. These phenomena were explained by changes in the structure of the gel-layer.
