Equilibrium Temperature Modeling at a Gulf Coast Refinery: Application of Site-Specific Monthly Bio-Heat Generation Factor

In 2014, Kirkland et al proposed the use of a monthly site-specific biological heat generation factor as an innovative approach to improve the biochemical heat gain estimation in the Argaman and Adams equilibrium temperature model for activated sludge systems. As part of ongoing work in this field, the authors are continuing to develop the 2014 work. This paper presents an additional study of the site-specific monthly bio-heat generation factor and expands its use to the refining industry with a plant that uses biological nitrification and denitrification processes. The importance of this work is to allow an appropriate evaluation of heating and cooling systems at activated sludge plants, particularly those that utilize the biological nitrification process and may be susceptible to upsets due to sensitivity of both low and high temperature levels. Approximately three years of data are presented. Phenol was the surrogate used to determine the bio heat generation factor. For the three years of data, the average absolute difference in the historical monthly average equilibrium temperature and the model predicted monthly average equilibrium temperature was approximately 0.35 °C and a maximum difference of approximately 1.3 °C.