Effect of Fixed Media Surface Area on Biofouling and Nutrients Removal in Fixed Film Membrane Bioreactor Treating Sewage at Medium and High Fluxes

This study investigates effects of fixed film surface area increment on removal efficacy and biofouling in membrane bioreactor (MBR). For this purpose, a lab-scale membrane bioreactor was used. Domestic wastewater was fed into it. Three different trials were conducted at different fluxes; 15, 20, and 25 L/m(2)/h (LMH). Every trial was conducted using four different scenarios by varying surface area of fixed media viz. 0, 100, 150, and 200 m(2)/m(3). Removal of pollutants viz. chemical oxygen demand (COD), biochemical oxygen demand (BOD), total organic content (TOC), total Khjdel nitrogen (TKN), and phosphorous was studied. In addition, cake resistance, pore resistance, and total resistance were also observed for aforementioned scenarios. The results demonstrated that pollutant removal efficiencies increased as the surface area per unit volume of bioreactor was increased. Conversely, the removal efficiency decreased with increase in the fluxes. In the case of biofouling, it increased while increasing the surface area or flux. The fixed media surface area increments proved beneficial in teims of removal efficiencies but at the cost of reduced operation time of MBR.