Abstract
To achieve stable removal of BOD, nitrogen and phosphorus, UF membrane process was combined with intermittent aeration sequencing batch activated sludge process (SBR process) . The effect of a hybrid system was studied comparing with that of a SBR system using bench scale plants.
Removal efficiencies of BOD and T-N in a hybrid system were higher than those in a SBR system, whereas removal efficiency of T-P was similar in both systems. In order to diminish UF membrane facility in size, a quadruple reactor type hybrid system was developed and it was successfully applied. A hybrid system was able to keep high removal efficiencies when the bulking of activated sludge occured. The flux of UF membrane was recovered by washing with 0.1N NaOH and 10% H2O2 solutions.
