Removal of phosphate from synthetic wastewater by struvite precipitation in a stirred reactor

Abstract

The cost of environmental protection and pollution prevention is increasing, above all because of stringent effluent quality standard. In that context, phosphorus impact on water pollution plays a major role because it accelerates eutrophication. This work addresses the problem of phosphorus recovery from synthetic wastewater by struvite precipitation. The general objective is to develop a methodology for an optimal design of an automated pilot reactor for the treatment of wastewater. In this perspective, preliminary precipitation experiments were carried out at laboratory scale to examine the effects of final pH, magnesium and phosphate concentrations in the influent. A thermodynamic model for struvite precipitation is proposed involving Davies activity coefficients. Keywords: Struvite, Precipitation, P-recovery, Stirred reactor, Modelling.