BIOLOGICAL PHOSPHORUS REMOVAL FROM MUNICIPAL WASTEWATER

Abstract

Enhanced biological phosphorus (Bio-P) removal process is a two step process involving exposure of microorganism to alternating anaerobic and aerobic conditions. During the anaerobic phase phosphorus is released and subsequently in the aerobic period removal of phosphorus takes place. In the present work an effort has been made to study both P-release and uptake, COD removal, volatile fatty acids (VFAs) and pH variations at 25°C and 10°C in sequential batch reactors (SBRs) using synthetic wastewater. During anaerobic phase maximum average P-released was 30% and 10.9% at 25°C and 10°C respectively. Though there were differences in temperatures and initial concentrations of released phosphorus yet the effluent phosphate concentrations was found to be almost same (94.6-95%) at both the temperatures. COD removal was found to be higher at higher temperature. COD reduction was more significant in aerobic zone. VFA reduction was also higher at higher temperature. pH value increased continuously in aerobic zone through in anaerobic zone it varied in slightly zig zag manner.