Importance of EBPR efficiency on energy demand of full-scale wastewater treatment plants

Abstract

Enhanced biological phosphorus removal processes (EBPR) are one of the most popular methods in nutrient control. Energy demand of wastewater treatment plants (WWTPs) is also very critical actual concern. In this study, relationship between fundamental characteristics of EBPR and energy demand was investigated in a large scale WWTP. Freshly collected wastewater and activated sludge samples were used in all experiments to obtain accurate results. Effect of both temperature and salinity on air demand in biological stages, which has the most significant impact on energy demand, were also considered in modeling efforts to obtain comparable results. Interactions between energy and soluble carbonaceous biochemical oxygen demand (sBOD(5)) removed by denitrifies in anaerobic and anoxic zones; acetate uptake rate were evaluated statistically using linear regression model. Effect of salinity on effluent PO(4)-P concentration and energy demand were also investigated by field-based measurements and obtained results evaluated statistically. ANOVA tests were also applied to assess acceptability of models from a statistical perspective. Obtained results indicated that EBPR processes would provide significant amount of energy savings in addition to adequate treatment efficiency.