Microcalorimetry: a tool to investigate aerobic, anoxic and anaerobic autotrophic and heterotrophic biodegradation

Biological modeling of wastewater processes has gained importance for their design, control and operation. However, this requires consistent information on the biological activity. Microcalorimetry has also been developed to investigate biological processes and measure bacterial metabolisms. This measurement is done on the basis of the heat (produced or consumed) and therefore has a wider range of applicability compared to other methods based on the chemical analyses of substrate consumption or product formation. For this purpose, a 2 L Bio-RC1 (Mettler-Toledo) has been modified to reach a resolution of 5–10 mW L−1 and applied to research projects on activated sludge characterization. Several calorimetric applications are presented regarding studies of biomass activity (useful to achieve kinetic and stoichiometric coefficients) and pollutants degradation in aerobic, anoxic and anaerobic conditions.