Biologically induced phosphate precipitation in heterotrophic nitrification processes of different microbial aggregates: Influences of nitrogen removal metabolisms and extracellular polymeric substances. (July 2022)

• Record Type: Journal Article
• Authors: Lin, Ziyuan; He, Lei; Zhou, Jian; Shi, Shuohui; He, Xuejie; Fan, Xing; Wang, Yingmu; He, Qiang
• Is Part Of: Bioresource technology. Volume 356(2022)
• Publication Date: 2022-07
• Subjects: Biological nutrients removal -- Heterotrophic nitrification -- Biologically induced phosphate precipitation -- Microbial aggregate -- Phosphorus recovery; 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.2022.127319
• Languages: English
• ISSNs: 0960-8524

Abstract

Graphical abstract: Highlights: Simultaneous P removal and recovery were achieved with heterotrophic nitrification. Biologically induced phosphate precipitation were different in biofilm and sludge. Biofilm had higher P removal performance and higher P content precipitate. Nitrogen removal metabolisms and EPS influenced phosphate precipitation. Migration behaviors of phosphate were different in distinct microbial aggregates. Abstract: Phosphorus (P) removal occurred in heterotrophic nitrification process, but its mechanism has not been fully explored. In this study, the P removal performances, pathways, and mechanisms in heterotrophic nitrification processes of different microbial aggregates (activated sludge and biofilm) were investigated. The results showed that the biofilm reactor had more efficient total nitrogen removal (98.65%) and phosphate removal (94.17%). Heterotrophic nitrification and denitrification processes generated alkalinity for biologically induced phosphate precipitation (BIPP), which contributed to 64.12%-78.81% of the overall P removal. The solid phase P content reached 48.03 mg/gSS with hydroxyapatite and calcium phosphate formation. The study clarified that biofilm was beneficial to BIPP because of the nitrogen removal metabolism and extracellular polymeric substance (EPS). Heterotrophic nitrogen removal metabolism was the driving force of BIPP, while EPS with abundant carboxyl and amide groups promoted the precipitation. The study would provide new insights into simultaneous nutrients removal and P recovery from wastewater.