A proposed chemical mechanism for biological phosphate removal in activated sludge treatment of wastewater

Abstract

This paper presents an alternative for the "all biological" phosphate removal model. It is postulated that a chemical substance in wastewater reacts with orthophosphate under anaerobic conditions to make the so-called luxury uptake of phosphorus possible in biological nutrient removal (BNR) activated sludge plants. Experimental evidence indicates that the reaction product, an organic phosphate, is the phosphate species that is taken up by organisms in the process of biological phosphate removal. The research on which this paper is based, forms part of a Ph.D. study and further research to confirm the initial observations and to identify the chemical agent involved in biological phosphorus removal is continuing.