Combined process of bio-contact oxidation-constructed wetland for blackwater treatment

Zhan Jin; Yangfei Zheng; Xiangyu Li; Chuanjun Dai; Kaiqin Xu; Ke Bei; Xiangyong Zheng; Min Zhao

doi:10.1016/j.biortech.2020.123891

Combined process of bio-contact oxidation-constructed wetland for blackwater treatment

Bioresour Technol. 2020 Nov:316:123891. doi: 10.1016/j.biortech.2020.123891. Epub 2020 Jul 21.

Authors

Zhan Jin¹, Yangfei Zheng², Xiangyu Li², Chuanjun Dai², Kaiqin Xu³, Ke Bei², Xiangyong Zheng⁴, Min Zhao²

Affiliations

¹ National and Local Joint Engineering Research Center of Ecological Treatment Technology for Urban Water Pollution, Wenzhou University, Wenzhou 325600, China. Electronic address: 20150080@wzu.edu.cn.
² National and Local Joint Engineering Research Center of Ecological Treatment Technology for Urban Water Pollution, Wenzhou University, Wenzhou 325600, China.
³ Center for Material Cycles and Waste Management Research, National Institute for Environmental Studies, 16-2 Onogawa Tsukuba, Ibaraki 305-8506, Japan. Electronic address: joexu@nies.go.jp.
⁴ National and Local Joint Engineering Research Center of Ecological Treatment Technology for Urban Water Pollution, Wenzhou University, Wenzhou 325600, China. Electronic address: 00121051@wzu.edu.cn.

PMID: 32777719
DOI: 10.1016/j.biortech.2020.123891

Abstract

In this study, a combined process of bio-contact oxidation and constructed wetland for blackwater treatment was assessed. The effects of hydraulic retention time and particle size on treatment performance were systematically studied. Additionally, microbial communities in the combined process were characterized. The results show that the removal efficiency of COD, TN, NH₄⁺-N, and TP under optimum conditions in this study were 81.6%, 56.1%, 42.2%, and 73.7%, respectively. The maximum nitrogen removal rate reached 16.5 g m^-2 d^-1 (3 d). N and P removed via direct plant absorption accounted for only 19.7% and 16.1% of the total system, respectively. Plants play a crucial role in the microbial community of constructed wetlands and influence the overall performance of the system. The biofilm on roots favored aerobic and heterotrophic bacteria such as the aerobic denitrification microorganisms of Pelagibacterium, Halomonas, and Zoogloea. Overall, the combined process is a suitable technique for the treatment of blackwater.

Keywords: Blackwater; Decentralized sewage system; Hydraulic retention time; Microbial communities; Particle size.

MeSH terms

Denitrification
Microbiota*
Nitrogen
Waste Disposal, Fluid
Wetlands*

Substances

Nitrogen