The relationship between energy production and simultaneous nitrification and denitrification via bioelectric derivation of microbial fuel cells at different anode numbers

Shan Huang; Guangcan Zhu; Xia Gu

doi:10.1016/j.envres.2020.109247

The relationship between energy production and simultaneous nitrification and denitrification via bioelectric derivation of microbial fuel cells at different anode numbers

Environ Res. 2020 May:184:109247. doi: 10.1016/j.envres.2020.109247. Epub 2020 Feb 11.

Authors

Shan Huang¹, Guangcan Zhu², Xia Gu³

Affiliations

¹ School of Energy and Environment, Southeast University, Nanjing, 210096, China; State Key Laboratory of Environmental Medicine Engineering, Ministry of Education, Southeast University, Nanjing, Jiangsu, 210096, China. Electronic address: 18270911541@163.com.
² School of Energy and Environment, Southeast University, Nanjing, 210096, China; State Key Laboratory of Environmental Medicine Engineering, Ministry of Education, Southeast University, Nanjing, Jiangsu, 210096, China. Electronic address: gc-zhu@seu.edu.cn.
³ School of Energy and Environment, Southeast University, Nanjing, 210096, China; State Key Laboratory of Environmental Medicine Engineering, Ministry of Education, Southeast University, Nanjing, Jiangsu, 210096, China. Electronic address: 839079682@qq.com.

PMID: 32065976
DOI: 10.1016/j.envres.2020.109247

Abstract

In this study, three microbial fuel cells (MFCs) with different numbers of anodes (i.e., 1A, 3A, and 5A) were constructed to study the effects of a multi-anode (MA) system on power generation performance and nitrogen (N) removal from low carbon (C)/N wastewater. The maximum power density of 3A-MFC was 236.7 mW m^-3, which was 2.6-fold and 1.2-fold that of 1A-MFC and 5A-MFC, respectively. The 3A-MFC system produced the highest total energy output in one cycle, approximately 41.7 mW h, which was 1.5-fold and 1.3-fold that of 1A-MFC and 5A-MFC, respectively. 3A-MFC also had the highest total N (TN) removal efficiency (71.1 ± 3.9%) and simultaneous nitrification and denitrification (SND) rate (93.5 ± 2.4%). An analysis of electron flow distribution in the 3A-MFC biocathode showed that electro-autotrophic denitrification accounted for 19% of the total denitrification in the last 135 h. Thereafter, the relationships between TN removal, anode number, and bioelectricity were systematically evaluated. TN removal efficiency had a good linear relationship with energy production (R² = 0.97539); TN removal was mainly dependent on SND. Generally, the MA-MFC configuration proposed in this study produced more electrical energy and improved TN removal by enhancing nitrification and heterotrophic and electro-autotrophic denitrification of the biocathode. The proposed method is therefore effective for enhancing N removal.

Keywords: Biocathode; Electricity generation; Electro-autotrophic denitrification; Multiple-anode MFC; SND.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Bioelectric Energy Sources*
Denitrification*
Electricity
Electrodes
Nitrification*
Wastewater

Substances

Waste Water