Nitrogen removal process optimization in New York City WPCPS: a case study of Wards Island WPCP

摘要

The New York City Department of Environmental Protection has been engaged in a continuousnprocess to develop a nitrogen removal program to reduce the nitrogen mass discharge from itsnwater pollution control plants, (WPCPs), from 49,158 kg/d to 20,105 kg/d by the year 2017 asnrecommended by the Long Island Sound Study. As part of the process, a comprehensive researchneffort was undertaken involving bench, pilot and full scale studies to identify the most effectivenway to upgrade and optimize the existing WPCPs. Aeration tank 13 (AT-13) at the Wards IslandnWPCP was particularly attractive as a full-scale research facility because its aeration tank with itsndedicated final settling tanks and RAS pumps could be isolated from the remaining treatmentnfacilities. The nitrogen removal performance of AT-13, which, at the time, was operated as an“basic step feed BNR Facility”, was evaluated and concurrently nitrification kinetic parametersnwere measured using in-situ bench scale experiments. Additional bench scale experimentsnprovided denitrification rates using different sources of carbon and measurement of thenmaximum specific growth rate of nitrifying bacteria. The combined findings were then used tonupgrade AT-13 to a “full” BNR facility with carbon and alkalinity addition. This paper will focus onnthe combined bench and full scale results that were the basis for the consequent upgrade.