Nitrification Comparison between Synthetic Wastewater and Secondary Effluent Using Membrane-Aerated Biofilm Reactor (MABR) Process

摘要

Two pilot-scale membrane aerated biofilm reactors (MABR) were operated for over 530 daysto compare the nitrification in both synthetic wastewater and secondary effluent, and toexamine the impacts of hydrodynamic shear caused by adjusting effluent recirculation onammonia removal. The results showed that secondary effluent had enhanced the nitrifyingbiofilm formation and/or detention. The ammonia removal efficiencies up to 0.262±0.024 and0.252±0.023 kgN/m~3/d were achieved for synthetic wastewater and secondary effluent,respectively. An optimum fluid mixing existed so that the balance between biofilm detachmentand substrate mass transfer can be maintained for maximum oxidation capacity. Furthermore,the optimum mixing conditions were found to be dependent of influent composition. Furtherevaluation shows that low mixing intensity is a good strategy for the initiation of nitrifyingbiofilm in MABR, especially for the treatment of wastewater of no organic carbon.