Effect of Partial Oxygen Pressures on Pollutant Removal with Membrane-Aerated Bioreactor

Abstract

The membrane-aerated bioreactor (MABR) was specially designed to evaluate its suitability for the treatment of an artificial sewage in laboratory. The paper presented the configuration of the MABR, the effect of variation of partial oxygen pressures on treatment efficiency (COD, NH4+-N, NO3--N), and the theoretical analysis on COD efficiency. The partial oxygen pressures were changed to investigate experimentally its influence on the removal of COD, NH4+-N and NO3--N. Results showed that when partial oxygen pressures was below 40KPa, COD and NH4+-N removal efficiency increased with its increasing, meanwhile, nitrification was the main control process in simultaneous nitrification and denitrification (SND); with partial oxygen pressures above 40KPa, the COD and NH4+-N removal efficiency wasnt affected by it, and denitrification became the main control process in SND. However, denitrification would be restrained if the partial oxygen pressure overtops a certain value. The partial oxygen pressure had more significant influence on COD than NH4+-N removal efficiencies. The reaction rate of COD remove in the MABR had zero-order reaction characteristics.