Struvite pellet crystallization in a high-strength nitrogen and phosphorus stream.
Struvite crystallization is a reliable method to recover nutrients from wastewater. Laboratory-scale experiments were conducted to investigate nutrient recovery from synthetic wastewater with high-strength orthophosphate and ammonia-nitrogen by the formation of struvite pellets. Without adjusting pH, struvite crystal growth environment was achieved in ammonia-nitrogen and orthophosphate concentration ranges of 100-1,000 and 221-2,214 mg/L, respectively. The mean size of the harvested struvite pellets was in the range of 3-4 mm. pH is an important factor indicating the process supersaturation. A range of pH 6.2-9.0 was tested in order to enhance nutrient removal efficiency. The results showed although higher N, P and Mg removals were achieved at higher pH values, over 95% N, P and Mg removals were still achieved at pH of 7.6. Recycling ratio of the clarifier supernatant to influent had no significant promotion of N or P removal.
State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai, China E-mail: liyongmei@tongji.edu.cn.
Yongmei
Y
Li
Mingyan
M
Liu
Zhiwen
Z
Yuan
Jinte
J
Zou
D003460:Crystallization; D006863:Hydrogen-Ion Concentration; D008274:Magnesium / Q000737:chemistry; D017616:Magnesium Compounds / Q000737:chemistry*; D009584:Nitrogen / Q000737:chemistry*; D010710:Phosphates / Q000737:chemistry*; D010758:Phosphorus / Q000737:chemistry*; D000069877:Struvite; D014865:Waste Disposal, Fluid / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000737:chemistry*
D017616:Magnesium Compounds; D010710:Phosphates; D014874:Water Pollutants, Chemical; D010758:Phosphorus; D000069877:Struvite; D008274:Magnesium; D009584:Nitrogen