Dynamics of dissolved organic matter and dissolved organic nitrogen during anaerobic/anoxic/oxic treatment processes

Gang Tang; Binrui Li; Bowei Zhang; Chen Wang; Guangci Zeng; Xing Zheng; Chongxuan Liu

doi:10.1016/j.biortech.2021.125026

Dynamics of dissolved organic matter and dissolved organic nitrogen during anaerobic/anoxic/oxic treatment processes

Bioresour Technol. 2021 Jul:331:125026. doi: 10.1016/j.biortech.2021.125026. Epub 2021 Mar 27.

Authors

Gang Tang¹, Binrui Li², Bowei Zhang¹, Chen Wang¹, Guangci Zeng¹, Xing Zheng³, Chongxuan Liu⁴

Affiliations

¹ State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control, School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen, 518055, PR China.
² State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control, School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen, 518055, PR China; School of Environment, China University of Geosciences, Wuhan, 430074, PR China.
³ State Key Laboratory of Eco-hydraulics in Northwest Arid Region, Xi'an University of Technology, Xi'an, 710048, PR China.
⁴ State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control, School of Environmental Science and Engineering, Southern University of Science and Technology, Shenzhen, 518055, PR China. Electronic address: liucx@sustech.edu.cn.

PMID: 33812138
DOI: 10.1016/j.biortech.2021.125026

Abstract

With Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) and fluorescence spectroscopy, this study investigated the transformation of dissolved organic matter (DOM) and nitrogen (DON) during the widely-applied anaerobic/anoxic/oxic (A²O) processes to provide molecular insights into the removal, generation, and reduction of DOM/DON species in different biological treatment units. Results indicated that the anaerobic process decomposed the macromolecules of influent DOM/DON and decreased their mass. The anoxic process denitrified DON and generated DOM, as indicated by the decreased molecule number of CHON and CHONS and the increased CHO and CHOS species, as well as the increased overall DOM intensities. DOM mineralization and ammonia nitrogen-DON conversion occurred in the oxic process. Aromaticity and unsaturation degree increased slightly after the A²O processes, which was correlated with the relative abundance of Proteobacteria (positively) and Bacteroidetes (negatively). The results have strong implications to the understanding of DOM/DON dynamics in wastewater treatment plants.

Keywords: Dissolved organic matter; Dissolved organic nitrogen; FT-ICR MS; Microbial community correlation; Municipal wastewater.

MeSH terms

Anaerobiosis
Mass Spectrometry
Nitrogen*
Water Purification*

Substances

Nitrogen