The Impact of Cold Weather Events on Biological Nutrient Removal


  • W. O. Khunjar, M. D. Strahota, P. Pitt, W. J. Gellner - Hazen and Sawyer

Wastewater treatment plants (WWTPs) performing biological nutrient removal (BNR) represent a primary line of defense against the discharge of nutrients to receiving water bodies. Cold and wet weather events at wastewater treatment plants are typically characterized by high flows, low temperatures, and wastewater with insufficient COD to nutrient ratios for optimal BNR . Exposure to these conditions can compromise the capacity and reliability of nutrient removal at WWTPs. Production of high quality effluent during and after these events is a critical need for WWTPs subject to enhanced nutrient removal (ENR) requirements (Neethling, Clark et al. 2010). Therefore, development of guidelines that describe strategies to effectively minimize the impact of extreme weather events on ENR facilities is needed. In order to develop appropriate strategies for this purpose, it is important to characterize the pattern and causes of sub-optimal BNR performance from cold and wet weather events at full-scale facilities. Compilation, review and publication of successful standard operation practices can facilitate improved operation of BNR facilities during these adverse weather events. In this work, we address this knowledge gap by developing a compendium of management practices geared towards maintaining effective BNR performance during cold and wet weather events.

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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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