Effect of intermittently aerate on the simultaneous nitrification and denitrification (SND) in MBR

A laboratory-scale intermittently aerate membrane was applied to treat domestic sewage. At hydraulic retention tims (HRT)of 6h and dissolved oxygen of 1~2mg/L in aeration, three aeration/non-aeration cycles including 60min/60min, 60min/90min and 90min/60min were experimented separately, which form microenvironment of aerobic/anoxia to reach simultaneous nitrification and denitrification. At a result, more than 90% of COD and NH₄⁺-N was removed, among which average 74% of TN was removed in aeration/non-aeration cycles of 60min/60min. at the same time, membrane flux could be renewed in initial level approximately by chemical cleaning.