Intensified nitrogen removal in constructed wetlands by novel spray aeration system and different influent COD/N ratios

Wei Wang; Xinshan Song; Fayun Li; Xiyan Ji; Meifang Hou

doi:10.1016/j.biortech.2020.123008

Intensified nitrogen removal in constructed wetlands by novel spray aeration system and different influent COD/N ratios

Bioresour Technol. 2020 Jun:306:123008. doi: 10.1016/j.biortech.2020.123008. Epub 2020 Feb 10.

Authors

Wei Wang¹, Xinshan Song², Fayun Li³, Xiyan Ji³, Meifang Hou⁴

Affiliations

¹ College of Ecological Technique and Engineering, Shanghai Institute of Technology, Shanghai 201418, China; College of Environmental Science and Engineering, State Environmental Protection Engineering Center for Pollution Treatment and Control in Textile Industry, Donghua University, Shanghai 201620, China.
² College of Environmental Science and Engineering, State Environmental Protection Engineering Center for Pollution Treatment and Control in Textile Industry, Donghua University, Shanghai 201620, China.
³ College of Ecological Technique and Engineering, Shanghai Institute of Technology, Shanghai 201418, China.
⁴ College of Ecological Technique and Engineering, Shanghai Institute of Technology, Shanghai 201418, China. Electronic address: mfhou@sit.edu.cn.

PMID: 32222426
DOI: 10.1016/j.biortech.2020.123008

Abstract

The degradation performance of organic matters and microorganism abundance variations of two horizontal subsurface flow constructed wetlands (HSSFCWs) with different influent COD/N ratios and a spray aeration system were investigated. Oxygen-enriched influent water was beneficial to enhance the abilities of nitrification and biodegradation of organic matters. Due to the sufficient carbon source supply under influent COD/N ratio of 8.0, the high removal performances of COD (93%), NH₄-N (85%) and total nitrogen (78%) were simultaneously obtained in HSSFCWs with a spray aeration system. The increase in nitrite and nitrate bacteria was beneficial to complete nitrification and improve NH₄-N removal. The increase in denitrifying bacteria contributed to complete denitrification and guaranteed the high removal efficiency of NO₃-N. The results suggested that the spray aeration combined with high influent COD/N ratios could achieve the high nitrogen removal in HSSFCWs.

Keywords: COD/N ratio; Constructed wetlands; Microbial community; Nitrification-denitrification; Spray aeration.

MeSH terms

Biological Oxygen Demand Analysis
Denitrification
Nitrification
Nitrogen*
Wetlands*

Substances

Nitrogen