Temperature Effects on Physiology of Biological Phosphorus Removal

Abstract

Phosphorus-removing sludge was enriched in an anaerobic-aerobic, acetate-fed, sequencing batch reactor at 20°C. Conversion of relevant compounds for biological phosphorus removal was studied at 5, 10, 20, and 30°C in separate batch tests. The stoichiometry of the anaerobic processes was insensitive to temperature changes. Some effect on aerobic stoichiometry was observed. In contrast, temperature had a strong influence on the kinetics of the processes under anaerobic as well as aerobic conditions. The anaerobic phosphorus-release (or acetate-uptake) rate showed a maximum at 20°C. However, a continuous increase was observed in the interval 5–30°C for the conversion rates under aerobic conditions. Based on these experiments, temperature coefficients for the different reactions were calculated. An overall anaerobic and aerobic temperature coefficient θ was found to be 1.078 (valid in the range 5°C <T< 20°C) and 1.057 (5°C <T< 30°C), respectively.