Removal of nitrogen and phosphorus pollutants from swine wastewater

This study investigated the simultaneous removal of nitrogen and phosphorus from swine wastewater by a magnesium ammonium phosphate crystallization. The precipitation of struvite was determined from swine wastewater, obtaining the optimal pH, Mg/N/P molar ratio, and reaction time were 9.0, 1.6/1/1.5 and 30 min, respectively. Ammonium and phosphate removal efficiencies were 98.1 ± 0.5% and 98.9 ± 0.4% under optimal conditions, and the highest crystallization mass obtained was 14.6 ± 0.6 g/L. Results illustrated that struvite precipitation is an efficient method for removing ammonium and phosphate in swine wastewater.