Articulating the Case for Sidestream Nutrient Removal to Enhance WRRF Capacity: One Year of Full-Scale Operating Experience

This paper describes the value of sidestream treatment of post-digestion dewatering recycle from the standpoint of increased gross treatment plant nitrogen removal capacity. One year of full-scale operating experience and treatment plant performance data are described, taking into account influent nitrogen loading and effluent nitrogen load reduction contributions associated with mainstream and sidestream treatment. Comparative cost data from a 2006 study comparing the cost of additional mainstream aeration volume versus the cost of the implemented sidestream treatment alternative are presented in order to show the comparative value of the sidestream treatment approach. Finally, current and projected operating costs for the sidestream system in both nitrification/denitrification and nitritation/denitritation modes of operation are presented to compare the potential for operational cost reductions on a per pound basis for nitrogen removal in the sidestream system.