BNR/ENR Model Calibration Experience - Key Modeling Parameters and Lessons Learned


  • R. J. Latimer, P. Pitt, J. Rohrbacher, K. Bilyk - Hazen and Sawyer

Over the past few years, utilization of advanced activated sludge process simulation models such as BioWin and GPS-X has increased significantly. These process simulation models are powerful tools for evaluation, optimization, and design of BNR/ENR plants. When considering stringent effluent nutrient permit limits, particularly ENR limits, utilization of a properly developed and calibrated model using site specific wastewater characterization is highly recommended. Site specific wastewater characterization and calibration of the model, when possible, is critical to achieving accurate simulation results for ENR plants.

Hazen and Sawyer has conducted many site specific wastewater characterization and model calibration projects for BNR/ENR plants over the past ten years, generally following the recommendations provided in the WERF document “Methods for Wastewater Characterization in Activated Sludge Modeling“. This paper will summarize the results of these efforts, provide a comparison of the site specific data to BioWin defaults, illustrate the impacts and key issues to BNR/ENR modeling and design, summarize issues identified when carrying out the sampling plans and plant calibration, summarize potential pitfalls and lessons learned, and provide recommendations for improving these efforts.

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Horizons Fall 2017 (pdf)

Horizons showcases significant water, wastewater, reuse, and stormwater projects and innovations that help our clients to achieve their goals, and can help you achieve yours. Articles are written by top engineers and process group leaders, demonstrating and explaining the beneficial application of a variety of technologies and tools.

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