Abstract
This paper describes an experimental study for the purpose of water quality improvement on wastewater (e. g. rapid sand filter backwashing drainage) recycling system in water purification plant, combined roughing filter and tank-submerged ceramic membrane filtration. Consequently, in this system, it was stably demonstrated that high removal rate of suspended solid and metal, such as iron, manganese aluminum and so on. And, membrane process could perform stable operation with membrane filtration flux 0.8m^3/m^2/day. Moreover, by arranging a sludge sedimentation zone at the bottom of membrane tank, the sludge concentration with the surroundings of the membrane was kept low, and cake accumulation on membrane surface was reduced. In the result, about 4∿5% of concentrated sludge was able to be obtained stably.
