MBR공정의 운전조건의 변화에 따른 여과성능 개선연구

Abstract

Membrane bioreactor (MBR) combining an activated sludge process and membrane filtration could achieve high nutrient removal efficiency and complete biomass retention without a secondary clarifier. Membrane fouling remains the most challenging issue in MBR operation and attracts considerable attention in MBR studies. The objective of this study is to investigate the influence of permeate flux, aeration mode and strength, and mixed liquor suspended solid (MLSS) on membrane filtration of small-scale MBR (the capacity 100㎥/d), which consisted of anaerobic, anoxic, and aeration tank coupled with membrane. Experiments were conducted with real MBR using real wastewater (BOD <250 mg/L, COD <220 mg/L, T-N <65 mg/L, T-P <8 mg/L, E-coli <100,000 no/mL). As a result, the increase of both permeate flux and MLSS increased TMP of MBR while the increase of aeration strength decreased the TMP. Compared to the existing operation conditions of MBR, the operation conditions of shorter filtration time (8 min on/ 2 min off) for a cycle and lower MLSS (<3000 mg/L) in MBR resulted in longer filtration duration time (about two times) as well as the reduction of cleaning chemical.