MODELING SLUDGE PRODUCTION TRENDS AT BLUE PLAINS WASTE-WATER TREATMENT-PLANT

The District of Columbia's Wastewater Treatment Plant at Blue Plains is undergoing a $400 million expansion and upgrade from 13.5 m3/s to 16.2m3/s. A large portion of this expenditure is for a permanent sludge management system. Both present and future sludge management plans feature multiple sludge processing and disposal options. To improve existing sludge operations and provide accurate planning for future facilities, sludge production models were developed from historical plant operating data. The historical data were evaluated and a macro and micro model developed for the Blue Plains WWTP. This paper describes the development, calibration and application of the micro model which assesses the primary, secondary, nitrification, and chemical sludge production. The model also describes subsequent sludge treatment processes and indicates the quantity of sludge discharged from the various flow schemes and the total sludge generated and treated at the plant. During model calibration the predicted total sludge production was within 8.5 percent of the actual values for the six year period examined.