Migration and transformation mechanism of phosphorus in waste activated sludge during anaerobic fermentation and hydrothermal conversion

JOURNAL OF HAZARDOUS MATERIALS

卷:403

Article

Shi, Yan^1,2  Chen, Zheng¹  Cao, Yang¹  Fan, Jiajun²  Clark, James H.²  Luo, Gang^1,3,4  Zhang, Shicheng^1,3,4 

[1] Fudan Univ, Shanghai Key Lab Atmospher Particle Pollut & Prev, Dept Environm Sci & Engn, Shanghai 200438, Peoples R China

[2] Univ York, Dept Chem, Green Chem Ctr Excellence, York YO10 5DD, N Yorkshire, England

[3] Shanghai Inst Pollut Control & Ecol Secur, Shanghai 200092, Peoples R China

[4] Shanghai Tech Serv Platformfor Pollut Control & R, Shanghai 200438, Peoples R China

关键词: Waste activated sludge (WAS);    Anaerobic fermentation (AF);    Hydrothermal conversion (HTC);    Phosphorus (P);    X-ray absorption near edge structure (XANES);   

DOI  :  10.1016/j.jhazmat.2020.123649

来源: Elsevier

【 摘 要 】

This study investigated migration and transformation mechanism of P in waste activated sludge (WAS) during anaerobic fermentation (AF) process and the subsequent hydrothermal conversion (HTC) process. Control of pH during the AF processes was found to be significant, whereby the use of acidic (pH = 5.5) or alkaline conditions (pH = 9.5) facilitated the release of either apatite phosphorus (AP) or non-apatite inorganic phosphorus (NAIP) and organic phosphorus, respectively. At the same pH of 9.5, NaOH promoted the transfer of P into liquid phase, and P in the solid phase was mainly in the form of NAIP. In contrast, Ca(OH)2 enhanced the incorporation of P into the solid products, with the P mainly in the form of AP. The subsequent HTC process promoted the NAIP transferred to AP, and the bioavailability of P in the HTC solid products was decreased. The P K-edge X-ray absorption near edge structure analysis provided detailed information about the phosphates. It demonstrated that the conversion of Ca8H2PO4.6.5H(2)O to Ca-5(PO4)(3).OH was facilitated by HTC under the alkaline condition. This study sheds lights on transformation mechanism of P speciations during AF and HTC processes, which would provide fundamental information for effective utilization of P in bio-wastes.

【 授权许可】

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