응집제를 활용한 침지형 MBR공정에서의 영양염류 제거 및 플럭스 향상 연구

Abstract

The MBR (membrane bioreactor) process is a conventional wastewater treatment process which has a lot of advantages such as high quality water assurance and stable wastewater treatment. In this research, a new MBR process composed of hollow fiber type membrane in the submerged form was developed and the efficiency of this MBR process were evaluated and discussed. In the MBR process, membrane contamination is one of the major problem which lead to reduce the MBR process and permeation flux efficiency by the increase of high TMP (transmembrane pressure). The conventional membrane process with the MBR-coagulation process and agglomeration compounds were developed in order to reduce the TMP increase and to increase the nutrient removal efficiency. For this study, the two coagulants such as Al2(SO4)3 and FeCl3 were selected and their optimal coagulant doses were determined. These two coagulants showed the excellent effects in controlling the TMP. Because suspended solid, floating matters and organic compound existing in the sludge forms a floc. Apart from this, precipitability and dehydration was better. Especially, in the conventional MBR-coagulation process the FeCl3 coagulant was the main factor for the removal of nitrogen and phosphorus and their removal efficiency was higher than the ordinary MBR process. Whereas in the case of Al2(SO4)3 removal efficiency of phosphorus was high while the nitrogen removal efficiency was relatively reduced. These results revelaed that Al2(SO4)3 has an effect on the nitrosomonas and nitrobacter which exist in the wastewater.