Research on recovery of phosphorus in high concentrations of phosphorus wastewater by struvite precipitation

W. Zhu, C. L. Yuan, Y. H. Xie,

Abstract

Struvite is an efficient slow-release compound fertilizer. Struvite precipitation method can not only remove phosphorus in wastewater, but also can recycle phosphorus in waste water and solve resource shortages problem. This article researches the effect of pH, contact time reaction, three crystal ions structures (Mg2+, NH4 +, PO4 3-) ratio and Ca2+on struvite precipitation and precipitation ingredients. The results show that when the pH was 9.5, the exposure reaction time was 20 min, the molar ratio of Mg2+:NH4 +:PO4 3-was 1.2:2:1, and the molar ratio of Mg2+:Ca2+ is 1:0.5 or more, the phosphorus removing and recycling effect on high concentration of phosphorus wastewater is remarkable.