Process Modeling for the Tri-City WPCP Expansion Project

Process modeling on the Tri-City WPCP Phase I Expansion project proved invaluable because it allowed the project team to address biological process challenges quickly and flexibly. After wastewater characterization, the process simulator BioWin™ was calibrated and validated to the existing plant. Going forward, process simulation provided the flexibility to evaluate plant performance under a variety of different process configurations and wastewater strengths. The model was used to evaluate overall plant performance of the existing plug flow with anoxic recycle/step feed activated sludge plant with a new parallel MBR train. Evaluations conducted at future flows and loads confirmed that the plant was appropriately sized for future expansion. Process modeling quickly showed that aeration basins need to be sized based on permit limitations in the “shoulder season” at the beginning of the dry weather permit cycle while the aeration system should be designed around the requirements of the maximum month later in the dry weather cycle.