Efficient carbon removal and excellent anti-clogging performance have been achieved in multilayer quartz sand horizontal subsurface flow constructed wetland for domestic sewage treatment

Jieyue Li; Jiajun Wang; Qin Zhang; Yanli Ding; Yanan Zhang; Ronghua Wang; Dunqiu Wang; Shaoyuan Bai

doi:10.1016/j.jenvman.2023.117516

Efficient carbon removal and excellent anti-clogging performance have been achieved in multilayer quartz sand horizontal subsurface flow constructed wetland for domestic sewage treatment

J Environ Manage. 2023 Jun 1:335:117516. doi: 10.1016/j.jenvman.2023.117516. Epub 2023 Feb 23.

Authors

Jieyue Li¹, Jiajun Wang¹, Qin Zhang², Yanli Ding³, Yanan Zhang⁴, Ronghua Wang⁵, Dunqiu Wang², Shaoyuan Bai⁶

Affiliations

¹ College of Environmental Science and Engineering, Guilin University of Technology, Guilin, 541004, China.
² College of Environmental Science and Engineering, Guilin University of Technology, Guilin, 541004, China; Guangxi Key Laboratory of Environmental Pollution Control Theory and Technology, Guilin, 541004, China.
³ Guangxi Collaborative Innovation Center for Water Pollution Control and Water Safety in Karst Areas, Guilin, 541004, China. Electronic address: dyl@glut.edu.cn.
⁴ College of Environmental Science and Engineering, Guilin University of Technology, Guilin, 541004, China; Guangxi Modern Industry College of Ecology and Environmental Protection, Guilin, 541004, China.
⁵ Hengsheng Water Environment Treatment Co., Ltd, Guilin 541004, China.
⁶ College of Environmental Science and Engineering, Guilin University of Technology, Guilin, 541004, China; Guangxi Collaborative Innovation Center for Water Pollution Control and Water Safety in Karst Areas, Guilin, 541004, China. Electronic address: baisy@glut.edu.cn.

PMID: 36840999
DOI: 10.1016/j.jenvman.2023.117516

Abstract

The present study aimed to investigate the application of a multilayer quartz sand substrate horizontal subsurface flow constructed wetland (HSFCW) for campus sewage treatment. It aimed to assess the pollutant removal efficiency and anti-clogging performance under the suggested maximum organic loading rate (250 g/m²/d). The results of the multilayer HSFCW (CW6) were compared to the mololayer HSFCW (CW1) for the removal of the chemical oxygen demand (COD), solid accumulation, and microbial communities. During operation, the combination conditions of high hydraulic loading rate (HLR) with low COD concentration were better for COD removal under a high organic loading rate (OLR) of 200-300 g/m²/d. The maximum removal rate reached 80.4% in CW6 under high HLR, which was 13.8% higher than that in CW1, showing better adsorption and biodegradation ability of organic matter. Impressive clogging resistance capacity was found in CW6 due to the lower contents of the insoluble organic matter (IOM) that are prone to clogging, indicating full degradation of organic matters, particularly IOM, in CW6 under high HLR. Less abundance of unclassified Chitinophagaceae (under low HLR), Pedobacter and Saccharibacteria_genera_incertae_sedis (under high HLR) in CW6, which contributed to aerobic membrane fouling, helped to prevent clogging. Moreover, Brevundimonas, Cloacibacterium, Citrobacter, Luteimonas contributed to IOM degradation, thus further enhancing the anti-clogging performance. In view of the better clogging resistance performance, the application of CW6 operated under high HLR and low COD concentrations was recommended to achieve economical, efficient, and steady COD removal for domestic sewage treatment in long-term operation.

Keywords: Clogging; Horizontal subsurface flow; Microbial community; Multilayer structure; Organic loading rate; Solids accumulation.

MeSH terms

Carbon
Nitrogen
Quartz
Sand*
Sewage
Waste Disposal, Fluid* / methods
Wetlands

Substances

Sand
Sewage
Quartz
Carbon
Nitrogen