Nitrogen and phosphorus recovery from livestock wastewater via magnesium ammonium phosphate precipitation: A critical review of methods, progress, and insights

• Published in: Journal of water process engineering Vol. 67; p. 106139
• Main Authors: Li, Jingtong, Chen, Chunyan, Luo, Zifeng, Qiu, Jinrong, Zhao, Li, Zhang, Jun, Xiao, Xue, Lin, Xiaojun, Wang, Xiujuan, Cai, Qianyi, Zeng, Jingwen, Tu, Hongxing, Zhou, Jianli
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.11.2024
• Subjects: Livestock wastewater; Magnesium ammonium phosphate; Precipitation; Slow-release fertilizer; Struvite; Precipitation; Magnesium ammonium phosphate; Slow-release fertilizer; Livestock wastewater; Struvite
• ISSN: 2214-7144; 2214-7144
• DOI: 10.1016/j.jwpe.2024.106139

Livestock wastewater contains a large amount of nitrogen and phosphorus, and how to effectively treat this wastewater has become a primary bottleneck limiting the development of the livestock industry. Recovering nitrogen and phosphorus from livestock wastewater represents the most promising solution for achieving nutrient recycling and wastewater purification. The magnesium ammonium phosphate (MAP) precipitation method is a technique that enables the simultaneous extraction of nitrogen and phosphorus from livestock wastewater, resulting in the production of struvite as a precipitate. This paper comprehensively reviews the characteristics of livestock wastewater and the nitrogen and phosphorus recovery mechanisms of the MAP process, detailing various influencing factors in the chemical precipitation process, including pH, element molar ratio, seed materials, and mixing methods. Furthermore, it evaluates the selection of different source materials, recovery efficiency, and economic feasibility. By analyzing electrochemical reactions and mechanisms, the study elucidates the applications and potential of the MAP process in treating livestock wastewater. While the majority of the precipitated products can be directly utilized as slow-release fertilizers in agriculture, they may also present certain risks to agricultural safety. The review concludes by summarizing the limitations and prospects of the MAP process, providing a technical and theoretical basis for the treatment and resource utilization of livestock wastewater. [Display omitted] •The research of struvite precipitation treating livestock wastewater is reviewed.•The recovery effects of different reaction conditions are compared.•Precipitation requires additional P/Mg sources to treat livestock wastewater.•The electrolysis reactor and mechanism with struvite precipitation are discussed.•Challenges and prospects of struvite precipitation technology are introduced.