Effects of individual volatile fatty acids (VFAs) on phosphorus recovery by magnesium ammonium phosphate. (June 2020)

• Record Type: Journal Article
• Authors: Lin, Hui; Chen, Yun; Shen, Nan; Deng, Yang; Yan, Wang; Ruhyadi, Roby; Wang, Guoxiang
• Is Part Of: Environmental pollution. Volume 261(2020)
• Publication Date: 2020-06
• Subjects: Volatile fatty acids (VFAs) -- Magnesium ammonium phosphate (MAP) -- Phosphorus recovery -- Alkaline fermentation liquid; Pollution -- Periodicals; Pollution -- Environmental aspects -- Periodicals; Environmental Pollution -- Periodicals; Pollution -- Périodiques; Pollution -- Aspect de l'environnement -- Périodiques; Pollution -- Effets physiologiques -- Périodiques; Pollution; Pollution -- Environmental aspects; Periodicals; Electronic journals; 363.73
• DOI: 10.1016/j.envpol.2020.114212
• Languages: English
• ISSNs: 0269-7491

Abstract

Abstract: Volatile fatty acids (VFAs) are a major component of dissolved organic matter in alkaline fermentation supernatants. In this study, effects of different VFAs (acetate, propionate, and butyrate) on phosphorus recovery, as magnesium ammonium phosphate (MgNH4 PO4 ·6H2 O, or MAP), were studied. Results showed that optimal pH was 9.5 and MAP purity was ∼70% in VFA-free wastewater. With VFA addition, MAP purities of precipitates were higher, reaching 75%–85%. The crystalline characterization of precipitates suggested that VFAs had a weak complexation ability with Mg 2+ and NH4 + . Further, pH changes during the MAP crystallization process were monitored and results indicated VFAs only contributed to the alkalinity condition, which, in turn, improved the MAP crystallization process. These data provide for a better understanding of P recovery by MAP precipitates from VFA-rich fermented supernatants. Graphical abstract: Image 1 Highlights: The effects of different individual VFAs on phosphorus recovery were studied. The optimal pH was 9.5 and MAP purity was about 70% in VFAs-free wastewater. MAP purities were higher and were reached to 75%–85% with VFAs addition. The enhancement of MAP purities with VFAs addition was related to the pH changes. Abstract : This study showed that volatile fatty acids (VFAs) had a weak complexation ability with Mg 2+ and NH4 + to form magnesium ammonium phosphate, only contributing the alkalinity condition, which, in turn, improved the MAP crystallization process.