Mathematical Modeling of Operation Process of Dynamic Membrane Bioreactor

Abstract

The effects of different influent C/N ratios on the removal efficiencies of COD, total nitrogen, ammonia, nitrite and nitrate were investigated in a dynamic membrane bioreactor (DMBR), which was used to treat synthetic domestic wastewater. A simplified activated sludge model(SASM) was proposed, which based on the activated sludge model No.1(ASM1). The results showed the effluent concentrations of COD were less than 50 mg·L-1 in the DMBR. The removal efficiencies of COD were more than 85% in the different C/N ratios. The effluent concentrations of total nitrogen and ammonia were gradually increased as the ratios of C/N decreased. When the ratio of C/N was more than 6.75, the removal efficiencies of total nitrogen and ammonia were more than 50% and 60%, respectively. The SASM was feasible for DMBR simulation and the simulated values of nitrite and nitrate almost equal to the experiment values