Effect of wetland plant fermentation broth on nitrogen removal and bioenergy generation in constructed wetland-microbial fuel cells

Highlights

● Fermentation broth facilitates N removal and energy yields in tertiary CW-MFC.

● Carbon sources are preferred for nitrogen removal over electricity generation.

● A mutual promotion relationship exists between acetic and humic acid in N removal.

● Humic acid boosts the abundances of functional genes relate to nitrogen metabolism.

Abstract

Constructed wetlands (CWs) are widely used as a tertiary treatment technology, and the addition of carbon sources can significantly improve advanced nitrogen removal. However, excessive carbon sources would lead to an increase in the effluent chemical oxygen demand in CWs, and microbial fuel cells (MFCs) can convert these into electricity. In this study, constructed wetland-microbial fuel cells (CW-MFCs) were built to achieve simultaneous nitrogen removal and electricity generation, using wetland plant litter fermentation broths as carbon sources. The total nitrogen removal in the groups with fermentation broth addition (FGs) reached 83.33%, which was 19.64% higher than that in the CG (group without fermentation broth), and the mean voltages in the FGs were at least 2.6 times higher than that of the CG. Furthermore, two main components of the fermentation broths, acetic acid (Ac) and humic acid (HA), were identified using a three-dimensional excitation emission matrix and gas chromatograph and added to CW-MFCs to explore the influence mechanism on the treatment performance. Denitrification and electrogenesis presented the same tendency: Ac&HA > Ac > CG’ (groups without Ac and HA). These results indicate that Ac and HA increased the abundance of functional genes associated with nitrogen metabolism and electron transfer. This study demonstrated that CW-MFC fermentation broth addition can be a potential strategy for the disposal of secondary effluent and bioelectricity generation.

Graphical abstract

Keywords

Constructed wetland / Microbial fuel cell / Nitrogen removal / Bioenergy generation / Carbon source

References

[1] APHA ( 1998). Standard Methods for the Examinations of Water and Wastewater. Washington, DC: American Public Health Association

[2] Chen M , Chang L , Zhang J , Guo F , Vymazal J , He Q , Chen Y . (2020). Global nitrogen input on wetland ecosystem: The driving mechanism of soil labile carbon and nitrogen on greenhouse gas emissions. Environmental Science and Ecotechnology, 4 : 100063

[3] Chen Y , Wen Y , Zhou J , Tang Z , Li L , Zhou Q , Vymazal J . (2014a). Effects of cattail biomass on sulfate removal and carbon sources competition in subsurface-flow constructed wetlands treating secondary effluent. Water Research, 59 : 1– 10

[4] Chen Y , Wen Y , Zhou Q , Vymazal J . (2014b). Effects of plant biomass on nitrogen transformation in subsurface-batch constructed wetlands: a stable isotope and mass balance assessment. Water Research, 63 : 158– 167

[5] Dash B P , Chaudhari S . (2005). Electrochemical denitrificaton of simulated ground water. Water Research, 39( 17): 4065– 4072

[6] Deng H , Ge L , Xu T , Zhang M , Wang X , Zhang Y , Peng H . (2011). Analysis of the metabolic utilization of carbon sources and potential functional diversity of the bacterial community in lab-scale horizontal subsurface-flow constructed wetlands. Journal of Environmental Quality, 40( 6): 1730– 1736

[7] Douglas G M , Maffei V J , Zaneveld J R , Yurgel S N , Brown J R , Taylor C M , Huttenhower C , Langille M G I . (2020). PICRUSt2 for prediction of metagenome functions. Nature Biotechnology, 38( 6): 685– 688

[8] Duan Y , Zhou A , Wen K , Liu Z , Liu W , Wang A , Yue X . (2019). Upgrading VFAs bioproduction from waste activated sludge via co-fermentation with soy sauce residue. Frontiers of Environmental Science & Engineering, 13( 1): 3

[9] Fu G , Huangshen L , Guo Z , Zhou Q , Wu Z . (2017). Effect of plant-based carbon sources on denitrifying microorganisms in a vertical flow constructed wetland. Bioresource Technology, 224 : 214– 221

[10] Fu G , Yu T , Huangshen L , Han J . (2018). The influence of complex fermentation broth on denitrification of saline sewage in constructed wetlands by heterotrophic nitrifying/aerobic denitrifying bacterial communities. Bioresource Technology, 250 : 290– 298

[11] Guo F , Xu F , Cai R , Li D , Xu Q , Yang X , Wu Z , Wang Y , He Q , Ao L , Vymazal J , Chen Y . (2022). Enhancement of denitrification in biofilters by immobilized biochar under low-temperature stress. Bioresource Technology, 347 : 126664

[12] Hansen A T , Dolph C L , Foufoula-Georgiou E , Finlay J C . (2018). Contribution of wetlands to nitrate removal at the watershed scale. Nature Geoscience, 11( 2): 127– 132

[13] Hua G Cheng Y Kong J Li M Zhao Z ( 2018). High-throughput sequencing analysis of bacterial community spatiotemporal distribution in response to clogging in vertical flow constructed wetlands. Bioresource Technology, 248(Pt B): 104− 112

[14] Huang B Fu G He C He H Yu C Pan X ( 2019). Ferroferric oxide loads humic acid doped anode accelerate electron transfer process in anodic chamber of bioelectrochemical system. Journal of Electroanalytical Chemistry (Lausanne, Switzerland), 851: 113464

[15] Hume N P , Fleming M S , Horne A J . (2002). Plant carbohydrate limitation on nitrate reduction in wetland microcosms. Water Research, 36( 3): 577– 584

[16] Liang D , He W , Li C , Wang F , Crittenden J C , Feng Y . (2021). Remediation of nitrate contamination by membrane hydrogenotrophic denitrifying biofilm integrated in microbial electrolysis cell. Water Research, 188 : 116498

[17] Luo Y , Zhang Y , Lang M , Guo X , Xia T , Wang T , Jia H , Zhu L . (2021). Identification of sources, characteristics and photochemical transformations of dissolved organic matter with EEM-PARAFAC in the Wei River of China. Frontiers of Environmental Science & Engineering, 15( 5): 96

[18] Ma J , Wang Z , He D , Li Y , Wu Z . (2015). Long-term investigation of a novel electrochemical membrane bioreactor for low-strength municipal wastewater treatment. Water Research, 78 : 98– 110

[19] Oon Y L , Ong S A , Ho L N , Wong Y S , Dahalan F A , Oon Y S , Lehl H K , Thung W E , Nordin N . (2018). Up-flow constructed wetland-microbial fuel cell for azo dye, saline, nitrate remediation and bioelectricity generation: From waste to energy approach. Bioresource Technology, 266 : 97– 108

[20] Puig S , Coma M , Desloover J , Boon N , Colprim J , Balaguer M D . (2012). Autotrophic denitrification in microbial fuel cells treating low ionic strength waters. Environmental Science & Technology, 46( 4): 2309– 2315

[21] Si Z , Song X , Wang Y , Cao X , Zhao Y , Wang B , Chen Y , Arefe A . (2018). Intensified heterotrophic denitrification in constructed wetlands using four solid carbon sources: Denitrification efficiency and bacterial community structure. Bioresource Technology, 267 : 416– 425

[22] Tao Z , Jing Z , Wang Y , Tao M , Luo H . (2021). Higher nitrogen removal achieved in constructed wetland with polyethylene fillers and NaOH-heating pre-treated corn stalks for advanced treatment of low C/N sewage. Environmental Science and Pollution Research International, 28( 11): 13829– 13841

[23] Wang X , Feng Y , Wang H , Qu Y , Yu Y , Ren N , Li N , Wang E , Lee H , Logan B E . (2009). Bioaugmentation for electricity generation from corn stover biomass using microbial fuel cells. Environmental Science & Technology, 43( 15): 6088– 6093

[24] Wang X , Tian Y , Liu H , Zhao X , Wu Q . (2019). Effects of influent COD/TN ratio on nitrogen removal in integrated constructed wetland-microbial fuel cell systems. Bioresource Technology, 271 : 492– 495

[25] Wu Z , Gao J , Cui Y , Li D , Dai H , Guo Y , Li Z , Zhang H , Zhao M . (2022). Metagenomics insights into the selective inhibition of NOB and comammox by phenacetin: Transcriptional activity, nitrogen metabolism and mechanistic understanding. Science of the Total Environment, 803 : 150068

[26] Yan J , Hu X , He Q , Qin H , Yi D , Lv D , Cheng C , Zhao Y , Chen Y . (2021). Simultaneous enhancement of treatment performance and energy recovery using pyrite as anodic filling material in constructed wetland coupled with microbial fuel cells. Water Research, 201 : 117333

[27] Yuan C , Zhao F , Zhao X , Zhao Y . (2020). Woodchips as sustained-release carbon source to enhance the nitrogen transformation of low C/N wastewater in a baffle subsurface flow constructed wetland. Chemical Engineering Journal, 392 : 124840

[28] Zhang C , Yin Q , Wen Y , Guo W , Liu C , Zhou Q . (2016). Enhanced nitrate removal in self-supplying carbon source constructed wetlands treating secondary effluent: The roles of plants and plant fermentation broth. Ecological Engineering, 91 : 310– 316

[29] Zhao C , Shang D , Zou Y , Du Y , Wang Q , Xu F , Ren L , Kong Q . (2020). Changes in electricity production and microbial community evolution in constructed wetland-microbial fuel cell exposed to wastewater containing Pb(II). Science of the Total Environment, 732 : 139127

[30] Zhao J , Mo F , Wu J , Hu B , Chen Y , Yang W . (2017). Clogging Simulation of Horizontal Subsurface-Flow Constructed Wetland. Environmental Engineering Science, 34( 5): 343– 349

[31] Zheng Y , Cao T , Zhang Y , Xiong J , Dzakpasu M , Yang D , Yang Q , Liu Y , Li Q , Liu S , Wang X . (2021). Characterization of dissolved organic matter and carbon release from wetland plants for enhanced nitrogen removal in constructed wetlands for low C-N wastewater treatment. Chemosphere, 273 : 129630

[32] Zhou Z , Wang K , Qiang J , Pang H , Yuan Y , An Y , Zhou C , Ye J , Wu Z . (2021). Mainstream nitrogen separation and side-stream removal to reduce discharge and footprint of wastewater treatment plants. Water Research, 188 : 116527

[33] Zhu H , Yan B , Xu Y , Guan J , Liu S . (2014). Removal of nitrogen and COD in horizontal subsurface flow constructed wetlands under different influent C/N ratios. Ecological Engineering, 63 : 58– 63

Acknowledgements

This work was supported by the National Natural Science Foundation of China (No. U20A20326), the Fundamental Research Funds for the Central Universities (No. 2020CDJDPT002), and Chongqing Talents Plan for Young Talents (No. CQY201905062).

Electronic Supplementary Material

Supplementary material is available in the online version of this article at https://doi.org/10.1007/s11783-022-1592-x and is accessible for authorized users.

RIGHTS & PERMISSIONS

2022 Higher Education Press