Low Cost Solutions that Combine Process Modeling, Optimization, and Pilot Testing to Comply with LOT Nitrogen and Phosphorus Standards at Two BNR Plants

The objective of this study was to utilize process modeling to predict effluent quality at design flow for two biological nutrient removal (BNR) facilities, and determine what additional improvements would be needed at each facility to meet limit of technology (LOT) nitrogen and phosphorus standards. Then, optimization, pilot-testing, and bench-testing were conducted to support this approach.Process modeling using calibrated BioWin models determined that side stream treatment and equalization, supplemental carbon addition, and increased nitrified recycle (NRCY) rates would optimize nitrogen and phosphorus removal at both plants. Zone dissolved oxygen (DO) control will also enhance denitrification and the effectiveness of the supplemental carbon. Both plants are also considering the Ostara process to improve BPR.