Original scientific paper

Heat Production Measurement of Activated Sludge by Calorimetry

N. Genç ; University of Kocaeli, Department of Environmental Engineering Kocaeli, Turkey
Ş. Yonsel ; Biyon Ltd. Samanyolu S. Ali Atif Han 29/2 Osmanbey, 34460 Sisli/Istanbul, Turkey

Abstract

Microbial heat generation (Qf ) is an important parameter to control a biological process. Qf can be determined by various methods. In this study, a system for online calorimetric measurements for activated sludge is developed: a pilot scale bioreactor of 100 L volume as a calorimeter. The calorimetric measurements were calibrated using the heat production of Saccharomyces cerevisiae consuming glucose so that Qf can also be measured using the relation of oxygen transfer rate OTR and the combustion enthalpy of
glucose (ΔcH0) (Qf = ΔcH0 OTR). Next, the Qf of activated sludge with glucose as substrate is measured using the verified experimental set. A constant value for OTR to calculate Qf could not be detected because the activated sludge comprises a mixture of
organic and unknown substrates and a heterogeneous flora of microorganisms. Heat energy production decreased during the experiment, pointing to a declining of microbial activity due to endogenous oxidation of the sludge.

Keywords

Activated sludge; calorimetric measurement; heat balance; microbial heat generation; oxygen transfer rate; yeast

Hrčak ID:

30663

URI

https://hrcak.srce.hr/30663

Publication date:

23.12.2008.

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