Filtration Resistance with Flow Rate on Membrane Surface in Treating Wastewater by Membrane Bioreactor

하수 MBR공정에 있어서 막표면 유속과 여과저항

Membrane fouling patterns in membrane bioreactor (MBR) include blockage of membrane pore, gel layer formation and sludge cake deposition on the membrane surface. Stirred dead-cell filtration has been widely used for fundamental studies on membrane fouling caused by soluble and colloidal matter during membrane filtration. In this study, the performance of MBR using a dead-end stirrer cell was carried out to investigate the characteristics of pollutants removal and membrane filtration resistance with hydraulic shear force on the surface of membrane module. Influent water qualities were on average <65 mgCOD/L, <21 mgT-N/L, and <6 mgT-P/L, <4500 mgMLSS/L, respectively. As a result, the membrane biofiltration achieved higher efficiencies of COD and T-P except T-N having lower efficiency <50% regardless of the hydraulic shear force. An increase in the hydraulic shear force resulted in a decrease in both transmembrane pressure (TMP) and total membrane filtration resistance. This suggests that higher hydraulic shear force is needed to improve membrane filtration resistance in operating a long-term filtration of MBR having a suitable permeate flux to enhance nitrogen removal efficiency.