Liu Nan, Li Ying-Ying, Ouyang Du-Juan, Zou Chang-Yong, Li Wei, Zhao Ji-Hong, Li Ji-Xiang, Wang Wen-Juan, Hu Ja-Jun
Key Laboratory of Pollution Treatment and Resource, China National Light Industry; Collaborative Innovation Center of Environmental Pollution Control and Ecological Restoration, Department of Material and Chemical Engineering, Zhengzhou University of Light Industry, Zhengzhou 450001, Henan, P. R. China.
Key Laboratory of Biomass Chemical Engineering of Ministry of Education, Institute of Industrial Ecology and Environment, College of Chemical and Biological Engineering, Zhejiang University, Yuquan Campus, Hangzhou 310027, P. R. China.
ACS Omega. 2021 Jul 6;6(28):17766-17775. doi: 10.1021/acsomega.0c05876. eCollection 2021 Jul 20.
The biological reduction of ferrous ethylenediaminetetraacetic acid (EDTA-Fe-NO and EDTA-Fe) is an important process in the integrated electrobiofilm reduction method, and it has been regarded as a promising alternative method for removing NO from industrial boiler flue gas. EDTA-Fe-NO and EDTA-Fe are crucial substrates that should be biologically reduced at a high rate. However, they inhibit the reduction processes of one another when these two substrates are presented together, which might limit further promotion of the integrated method. In this study, an integrated electrobiofilm reduction system with high reduction rates of EDTA-Fe-NO and EDTA-Fe was developed. The dynamic changes of microbial communities in the electrobiofilms were mainly investigated to analyze the changes during the reduction of these two substrates under different conditions. The results showed that compared to the conventional chemical absorption-biological reduction system, the reduction system exhibited better performance in terms of resistance to substrate shock loading and high microbial diversities. High-throughput sequencing analysis showed that , and were the dominant genera (>25% each) during the process of EDTA-Fe-NO reduction. had the ability to endure the shock loading of EDTA-Fe, and the relative abundance of under abnormal operation conditions was up to 30.82%. was the main bacteria for reducing nitrate by electrons and the relative abundance still exhibited 16.11% under shock loading. Furthermore, higher microbial diversity and stable reactor operation were achieved when the concentrations of EDTA-Fe-NO and EDTA-Fe approached the same value (9 mmol·L).
乙二胺四乙酸亚铁（EDTA-Fe-NO和EDTA-Fe）的生物还原是集成电生物膜还原法中的一个重要过程，并且它已被视为一种从工业锅炉烟气中去除NO的有前景的替代方法。EDTA-Fe-NO和EDTA-Fe是关键底物，应以高速率进行生物还原。然而，当这两种底物同时存在时，它们会相互抑制还原过程，这可能会限制该集成方法的进一步推广。在本研究中，开发了一种对EDTA-Fe-NO和EDTA-Fe具有高还原率的集成电生物膜还原系统。主要研究了电生物膜中微生物群落的动态变化，以分析在不同条件下这两种底物还原过程中的变化。结果表明，与传统的化学吸收-生物还原系统相比，该还原系统在抗底物冲击负荷和高微生物多样性方面表现出更好的性能。高通量测序分析表明，在EDTA-Fe-NO还原过程中， 、 和 是优势菌属（各占>25%）。 有能力承受EDTA-Fe的冲击负荷，在异常运行条件下 的相对丰度高达30.82%。 是通过电子还原硝酸盐的主要细菌，在冲击负荷下其相对丰度仍为16.11%。此外，当EDTA-Fe-NO和EDTA-Fe的浓度接近相同值（9 mmol·L）时，实现了更高的微生物多样性和稳定的反应器运行。
