title: Clarification of phosphorus fractions and phosphorus release enhancement mechanism related to pH during waste activated sludge treatment.
abstract: This study aimed to clarify phosphorus (P) fractions in waste activated sludge (WAS) and explore release performance and enhancement mechanism of different P species related to pH. Results showed that inorganic P (IP) was the major P fraction in raw sludge (87.86% of total solid P), and non-apatite inorganic P (NAIP), the most labile P forms, occupied 81.30% of IP, suggesting that WAS could be selected as potential substitution of phosphate rock. The optimized acid and alkaline conditions were pH=4 and pH=12 for molybdate reactive P accumulation, increased by 311.20mg/L and 479.18mg/L compared to raw sludge, which were 3.80 and 5.84 times higher than that of control, respectively. The mechanism study demonstrated that high pH promoted NAIP release, and apatite P was sensitive to low pH. Moreover, the releasable and recoverable P depended on both fractions of different P species in sludge and pH adjustment for sludge treatment.
authors.affiliation: State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology (SKLUWRE, HIT), 202 Haihe Road, Harbin 150090, China.
authors.forename: Zhang-Wei
authors.initials: ZW
authors.lastname: He
authors.affiliation: Key Laboratory of Environmental Biotechnology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Haidian District, Beijing 100085, China.
authors.forename: Wen-Zong
authors.initials: WZ
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology (SKLUWRE, HIT), 202 Haihe Road, Harbin 150090, China.
authors.forename: Ling
authors.initials: L
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology (SKLUWRE, HIT), 202 Haihe Road, Harbin 150090, China.
authors.forename: Cong-Cong
authors.initials: CC
authors.lastname: Tang
authors.affiliation: State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology (SKLUWRE, HIT), 202 Haihe Road, Harbin 150090, China.
authors.forename: Ze-Chong
authors.initials: ZC
authors.lastname: Guo
authors.affiliation: State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology (SKLUWRE, HIT), 202 Haihe Road, Harbin 150090, China.
authors.forename: Chun-Xue
authors.initials: CX
authors.lastname: Yang
authors.affiliation: State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology (SKLUWRE, HIT), 202 Haihe Road, Harbin 150090, China; Key Laboratory of Environmental Biotechnology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Haidian District, Beijing 100085, China. Electronic address: waj0578@hit.edu.cn.
authors.forename: Ai-Jie
authors.initials: AJ
authors.lastname: Wang
mesh_terms: D001031:Apatites; D006863:Hydrogen-Ion Concentration; D010710:Phosphates / Q000737:chemistry; D010758:Phosphorus / Q000737:chemistry*; D012722:Sewage / Q000737:chemistry*
chemical_list: D001031:Apatites; D010710:Phosphates; D012722:Sewage; D010758:Phosphorus
keywords: Enhancement mechanism; Molybdate reactive P accumulation; Phosphorus species; Waste activated sludge; pH