{"title":"生物膜电极反应器中混合电子供体供应的氮去除性能和电子竞争机理研究","authors":"Xin Yuan, Chunfang Chao, Jiaojiao Niu, Jinxin Song, Yiwen Liu, Siyuan Zhai, Yingxin Zhao","doi":"10.1016/j.eehl.2025.100153","DOIUrl":null,"url":null,"abstract":"<div><div>In this study, a unique electrode configuration in the form of an “inverted T” was developed in the biofilm electrode reactor (BER), enabling superior nitrogen removal via the synergistic effect of hydrogen autotrophic denitrification and heterotrophic denitrification. In contrast to the sole heterotrophic denitrification in the biofilm reactor (BR), weak electric stimulation in the BER system promoted <em>in situ</em> hydrogen production as well as electron transport and utilization, resulting in a notable 20% improvement in <span><math><mrow><msubsup><mtext>NO</mtext><mn>3</mn><mo>-</mo></msubsup></mrow></math></span> removal efficiency for both influent COD/N ratios. Conversely, notable <span><math><mrow><msubsup><mtext>NO</mtext><mn>2</mn><mo>-</mo></msubsup></mrow></math></span> accumulation occurred under both COD/N ratios, with concentrations ranging from 6.0 to 8.0 mg/L. The enrichment of non-heterotrophic denitrifiers, such as <em>Thermomonas, Pelomonas,</em> and <em>Hydrogenophaga,</em> was observed in the BER with a relative abundance exceeding 1.0%, contributing to the hydrogen autotrophic denitrification pathway. Based on the outcomes of the multiple electron donor utilization in the coexistence of different electron acceptor combinations, despite H<sub>2</sub> serving as an additional electron donor in the BER, electron competition was still detectable. Notably, nitrite reductase (Nir) emerged as the weakest competitor, resulting in a constrained <span><math><mrow><msubsup><mtext>NO</mtext><mn>2</mn><mo>-</mo></msubsup></mrow></math></span> reduction capacity. Based on the analysis of the electron competition characteristic, the potential <span><math><mrow><msubsup><mtext>NO</mtext><mn>3</mn><mo>-</mo></msubsup></mrow></math></span> metabolic pathway in the BER system was primarily driven by heterotrophic denitrification processes. The introduced electricity in the BER system was favorable for facilitating nitrogen removal through <em>in situ</em> production of hydrogen, direct supply of electrons from the electrode, improvement of functional microbial activity, and enhancement of enzymatic activity.</div></div>","PeriodicalId":29813,"journal":{"name":"Eco-Environment & Health","volume":"4 2","pages":"Article 100153"},"PeriodicalIF":0.0000,"publicationDate":"2025-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Mechanistic insights into nitrogen removal performance and electron competition with mixed electron donor supply in a biofilm electrode reactor\",\"authors\":\"Xin Yuan, Chunfang Chao, Jiaojiao Niu, Jinxin Song, Yiwen Liu, Siyuan Zhai, Yingxin Zhao\",\"doi\":\"10.1016/j.eehl.2025.100153\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><div>In this study, a unique electrode configuration in the form of an “inverted T” was developed in the biofilm electrode reactor (BER), enabling superior nitrogen removal via the synergistic effect of hydrogen autotrophic denitrification and heterotrophic denitrification. In contrast to the sole heterotrophic denitrification in the biofilm reactor (BR), weak electric stimulation in the BER system promoted <em>in situ</em> hydrogen production as well as electron transport and utilization, resulting in a notable 20% improvement in <span><math><mrow><msubsup><mtext>NO</mtext><mn>3</mn><mo>-</mo></msubsup></mrow></math></span> removal efficiency for both influent COD/N ratios. Conversely, notable <span><math><mrow><msubsup><mtext>NO</mtext><mn>2</mn><mo>-</mo></msubsup></mrow></math></span> accumulation occurred under both COD/N ratios, with concentrations ranging from 6.0 to 8.0 mg/L. The enrichment of non-heterotrophic denitrifiers, such as <em>Thermomonas, Pelomonas,</em> and <em>Hydrogenophaga,</em> was observed in the BER with a relative abundance exceeding 1.0%, contributing to the hydrogen autotrophic denitrification pathway. Based on the outcomes of the multiple electron donor utilization in the coexistence of different electron acceptor combinations, despite H<sub>2</sub> serving as an additional electron donor in the BER, electron competition was still detectable. Notably, nitrite reductase (Nir) emerged as the weakest competitor, resulting in a constrained <span><math><mrow><msubsup><mtext>NO</mtext><mn>2</mn><mo>-</mo></msubsup></mrow></math></span> reduction capacity. Based on the analysis of the electron competition characteristic, the potential <span><math><mrow><msubsup><mtext>NO</mtext><mn>3</mn><mo>-</mo></msubsup></mrow></math></span> metabolic pathway in the BER system was primarily driven by heterotrophic denitrification processes. The introduced electricity in the BER system was favorable for facilitating nitrogen removal through <em>in situ</em> production of hydrogen, direct supply of electrons from the electrode, improvement of functional microbial activity, and enhancement of enzymatic activity.</div></div>\",\"PeriodicalId\":29813,\"journal\":{\"name\":\"Eco-Environment & Health\",\"volume\":\"4 2\",\"pages\":\"Article 100153\"},\"PeriodicalIF\":0.0000,\"publicationDate\":\"2025-05-07\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Eco-Environment & Health\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S2772985025000225\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"\",\"JCRName\":\"\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Eco-Environment & Health","FirstCategoryId":"1085","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S2772985025000225","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
Mechanistic insights into nitrogen removal performance and electron competition with mixed electron donor supply in a biofilm electrode reactor
In this study, a unique electrode configuration in the form of an “inverted T” was developed in the biofilm electrode reactor (BER), enabling superior nitrogen removal via the synergistic effect of hydrogen autotrophic denitrification and heterotrophic denitrification. In contrast to the sole heterotrophic denitrification in the biofilm reactor (BR), weak electric stimulation in the BER system promoted in situ hydrogen production as well as electron transport and utilization, resulting in a notable 20% improvement in removal efficiency for both influent COD/N ratios. Conversely, notable accumulation occurred under both COD/N ratios, with concentrations ranging from 6.0 to 8.0 mg/L. The enrichment of non-heterotrophic denitrifiers, such as Thermomonas, Pelomonas, and Hydrogenophaga, was observed in the BER with a relative abundance exceeding 1.0%, contributing to the hydrogen autotrophic denitrification pathway. Based on the outcomes of the multiple electron donor utilization in the coexistence of different electron acceptor combinations, despite H2 serving as an additional electron donor in the BER, electron competition was still detectable. Notably, nitrite reductase (Nir) emerged as the weakest competitor, resulting in a constrained reduction capacity. Based on the analysis of the electron competition characteristic, the potential metabolic pathway in the BER system was primarily driven by heterotrophic denitrification processes. The introduced electricity in the BER system was favorable for facilitating nitrogen removal through in situ production of hydrogen, direct supply of electrons from the electrode, improvement of functional microbial activity, and enhancement of enzymatic activity.
期刊介绍:
Eco-Environment & Health (EEH) is an international and multidisciplinary peer-reviewed journal designed for publications on the frontiers of the ecology, environment and health as well as their related disciplines. EEH focuses on the concept of “One Health” to promote green and sustainable development, dealing with the interactions among ecology, environment and health, and the underlying mechanisms and interventions. Our mission is to be one of the most important flagship journals in the field of environmental health.
Scopes
EEH covers a variety of research areas, including but not limited to ecology and biodiversity conservation, environmental behaviors and bioprocesses of emerging contaminants, human exposure and health effects, and evaluation, management and regulation of environmental risks. The key topics of EEH include:
1) Ecology and Biodiversity Conservation
Biodiversity
Ecological restoration
Ecological safety
Protected area
2) Environmental and Biological Fate of Emerging Contaminants
Environmental behaviors
Environmental processes
Environmental microbiology
3) Human Exposure and Health Effects
Environmental toxicology
Environmental epidemiology
Environmental health risk
Food safety
4) Evaluation, Management and Regulation of Environmental Risks
Chemical safety
Environmental policy
Health policy
Health economics
Environmental remediation