Phosphorus recovery as vivianite from waste activated sludge via optimizing iron source and pH value during anaerobic fermentation. (December 2019)

• Record Type: Journal Article
• Authors: Cao, Jiashun; Wu, Yang; Zhao, Jianan; Jin, Shuo; Aleem, Muhammad; Zhang, Qin; Fang, Fang; Xue, Zhaoxia; Luo, Jingyang
• Is Part Of: Bioresource technology. Volume 293(2019)
• Publication Date: 2019-12
• Subjects: Phosphorus (P) recovery -- Vivianite -- Waste activated sludge (WAS) -- Anaerobic fermentation (AF) -- Clostridiaceae; Biomass -- Periodicals; Biomass energy -- Periodicals; Bioremediation -- Periodicals; Agricultural wastes -- Periodicals; Factory and trade waste -- Periodicals; Organic wastes -- Periodicals; Bioénergie -- Périodiques; Déchets agricoles -- Périodiques; Déchets industriels -- Périodiques; Déchets organiques -- Périodiques; Déchets (Combustible) -- Périodiques; 662.88
• DOI: 10.1016/j.biortech.2019.122088
• Languages: English
• ISSNs: 0960-8524

Abstract

Graphical abstract: Highlights: The optimal conditions for vivianite were pH 6.0–9.0, PO4 3− >5 mg/L and Fe/P 1.5. Most of Fe 2+ and PO4 3− were simultaneously released in FeCl3 -pH3 dosing sludge. Clostridiaceae was dominant in FeCl3 -pH3 reactors that induced Fe 3+ reduction. The P recovery efficiency as vivianite from WAS fermentation could be 82.60%. Abstract: This study presented an innovative method for phosphorus (P) recovery as vivianite from waste activated sludge (WAS) via optimizing iron dosing and pH value during anaerobic fermentation (AF). The optimal conditions for vivianite formation were in the pH range of 6.0–9.0 with initial PO4 3− >5 mg/L and Fe/P molar ratio of 1.5. Notably, FeCl3 showed advantages over ZVI for the simultaneous release of Fe 2+ and PO4 3− during WAS fermentation, especially in acidic conditions. The FeCl3 dosing at pH 3.0 could contribute to 78.81% Fe 2+ release and 85.69% of total PO4 3− release from WAS. They were ultimately recovered in the form of high-purity vivianite (93.67%). Clostridiaceae (40.25%) was the predominant bacteria in FeCl3 -pH3 reactors, which played key roles in inducing dissimilatory iron reduction for Fe 2+ formation. Therefore, P recovery as vivianite from WAS fermentation might be a promising and highly valuable approach to relieve the P crisis.