Kinetic comparisons of mesophilic and thermophilic aerobic biomass.

Kinetic parameters describing growth and decay of mesophilic (30 degrees C) and thermophilic (55 degrees C) aerobic biomass were determined in continuous and batch experiments by using oxygen uptake rate measurements. Biomass was cultivated on a single soluble substrate (acetate) in a mineral medium. The intrinsic maximum growth rate ( micro (max)) at 55 degrees C was 0.

Mesophilic and thermophilic activated sludge post treatment of anaerobic effluent. Sludge and wastewater characterisation using batch experiments.

Anaerobic pretreated paper process water was characterized in terms of readily biodegradable, slowly biodegradable, very slowly biodegradable and inert wastewater fractions under mesophilic and thermophilic conditions. The anaerobic pretreated paper process water contained a relatively high amount of slowly biodegradable components and few easily biodegradable components as indicated by the ratio of short-term BOD over the BOD5. Wastewater readily biodegradable COD, determined as short-term BOD, was almost similar when measured under both temperature conditions.

Effect of sulfate and nitrate on acetate conversion by anaerobic microorganisms in a freshwater sediment.

Acetate is quantitatively the most important substrate for methane production in a freshwater sediment in The Netherlands. In the presence of alternative electron acceptors the conversion of acetate by methanogens was strongly inhibited. By modelling the results, obtained in experiments with and without (13)C-labelled acetate, we could show that the competition for acetate between methanogens and sulfate reducers is the main cause of inhibition of methanogenesis in the sediment.