Computational Fluid Dynamics Modeling and Validation Testing of Peripheral Feed Peripheral Overflow Clarifiers at the East Bay Municipal Utility District Main Wastewater Treatment Plant

The East Bay Municipal Utility District (EBMUD) owns and operates the Main Wastewater Treatment Plant. The plant has twelve 140-ft diameter peripheral feed peripheral overflow (PFPO) secondary clarifiers. EBMUD is in the process of rehabilitating these clarifiers and worked with Hazen to define optimization opportunities that would result in improved performance. This paper presents the application of a CFD model for the evaluation and optimization of the EBMUD PFPO clarifiers; and the validation testing performed to confirm the successful implementation of the proposed modifications. While there is minimal literature on CFD modeling of PFPO clarifiers, the study demonstrates that it can be done with great success. The original modeling resulted in recommended modifications to the existing clarifiers and predicted improvements of 25% in effluent quality. Validation testing after two clarifiers were modified, proved the modifications were valuable and confirmed over 30% improvement in effluent quality.