Temperature modeling in activated sludge systems: a case study.

Jacek Makinia; Scott A Wells; Piotr Zima

doi:10.2175/106143005x67449

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PubMed · 16274087

Temperature modeling in activated sludge systems: a case study.

Jacek Makinia·Scott A Wells·Piotr Zima

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Abstract

A model of temperature dynamics was developed as part of a general model of activated-sludge reactors. Transport of heat was described by the one-dimensional, advection-dispersion equation, with a source term based on a theoretical heat balance over the reactor. The model was compared to several reference models, including a tanks-in-series model and the dispersion model with heat components neglecting biochemical-energy inputs and other activated-sludge, heat-balance terms. All the models were tested under steady-state and dynamic conditions at a full-scale facility, the Rock Creek wastewater treatment plant in Hillsboro, Oregon, using meteorological data from a station located 16 km from the plant. The dispersion model and tanks-in-series model matched in situ temperature data with absolute-mean errors less than 0.1 degrees C. Neglecting biochemical-heat-energy inputs in the activated-sludge reactor underestimated temperatures by up to 0.5 degrees C. The biochemical-heat-energy inputs accounted for 30 to 40% of the total heat flux throughout the year.

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Bioreactors Environment Models, Theoretical Sewage Temperature Time Factors Journal Article Research Support, Non-U.S. Gov't

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Jacek Makinia, Scott A Wells, Piotr Zima. Temperature modeling in activated sludge systems: a case study.. https://doi.org/10.2175/106143005x67449

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