Abstract

Phosphorus (P) removal is a significant issue in wastewater treatment. This study applies Fe-Al composite coagulant to the advanced treatment of different P forms in biological effluent. For 90% total P removal, the dosage of FeCl3-AlCl3 composite coagulant reduces by 27.19% and 43.28% than FeCl3 and AlCl3 only, respectively. Changes in effluent P forms could explain the phenomenon of composite coagulant dosage reduction. The suspended P in the effluent of composite coagulant is easier removed by precipitation than single coagulant. In this study, the hydrolysis speciations of Fe3+, Fe2+, and Al3+ at a pH range are calculated by Visual MINTEQ. Changes in the morphology of metal hydroxides correlate with P removal at pH 4–9. Besides, analyses of scanning electron microscope (SEM), Fourier transformed infrared (FTIR), and X-ray photoelectron spectroscopy (XPS) are performed on the coagulation precipitations. Fe2+ reacts directly with P to form flocs of Fe3(PO4)2, and Al2(SO4)3 assists in the sedimentation of the small-volume flocs. Al13 is a significant hydrolysis product of Al3+, and Fe and P would substitute for the peripheral AlVI of the Al13 structure to form stable Fe–O–Al covalent bonds.

Details

Title
Advanced removal of phosphorus from urban sewage using chemical precipitation by Fe-Al composite coagulants
Author
Xu, Hongbin 1 ; Wei, Songyu 2 ; Li, Guoqiang 1 ; Guo, Baolei 1 

 Zhengzhou University, School of Ecology and Environment, Zhengzhou, China (GRID:grid.207374.5) (ISNI:0000 0001 2189 3846) 
 Zhengzhou University, School of Water Conservancy and Transportation, Zhengzhou, China (GRID:grid.207374.5) (ISNI:0000 0001 2189 3846) 
Pages
4918
Publication year
2024
Publication date
2024
Publisher
Nature Publishing Group
e-ISSN
20452322
Source type
Scholarly Journal
Language of publication
English
ProQuest document ID
2932706744
Copyright
© The Author(s) 2024. This work is published under http://creativecommons.org/licenses/by/4.0/ (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.