Citation:
Yayi Wang, Yongzhen Peng, Tom Stephenson, Effect of influent nutrient ratios and
hydraulic retention time (HRT) on simultaneous phosphorus and nitrogen removal
in a two-sludge sequencing batch reactor process, Bioresource Technology, Volume
100, Issue 14, July 2009, Pages 3506-3512
Abstract:
A laboratory-scale anaerobic–anoxic/nitrification sequencing batch reactor (A2N-
SBR) fed with domestic wastewater was operated to examine the effect of varying
ratios of influent COD/P, COD/TN and TN/P on the nutrient removal. With the
increased COD/P, the phosphorus removals exhibited an upward trend. The influent
TN/P ratios had a positive linear correlation with the phosphorus removal
efficiencies, mainly because nitrates act as electron acceptors for the
phosphorus uptake in the A2N-SBR. Moreover, it was found that lower COD/TN
ratio, e.g. 3.5, did not significantly weaken the phosphorus removal, though the
nitrogen removal first decreased greatly. The optimal phosphorus and nitrogen
removals of 94% and 91%, respectively were achieved with influent COD/P and COD/
TN ratios of 19.9 and 9.9, respectively. Additionally, a real-time control
strategy for A2N-SBR can be undertaken based on some characteristic points of
pH, redox potential (ORP) and dissolved oxygen (DO) profiles in order to obtain
the optimum hydraulic retention time (HRT) and improve the operating reliabilit
