Open AccessPerformance and Microbial Community Analysis of an Electrobiofilm Reactor Enhanced by Ferrous-EDTA
Author(s) -
Nan Liu,
Yingying Li,
Ouyang Dujuan,
Changyong Zou,
Wei Li,
Ji-Hong Zhao,
Jixiang Li,
Wenjuan Wang,
Ja-jun Hu
Publication year - 2021
Publication title -
acs omega
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.779
H-Index - 40
ISSN - 2470-1343
DOI - 10.1021/acsomega.0c05876
Subject(s) - ferrous , nitrilotriacetic acid , chemistry , ethylenediaminetetraacetic acid , nox , chelation , microbial population biology , chryseobacterium , napa , nuclear chemistry , bacteria , inorganic chemistry , biochemistry , biology , organic chemistry , gene , genetics , combustion , 16s ribosomal rna
The biological reduction of ferrous ethylenediaminetetraacetic acid (EDTA-Fe II -NO and EDTA-Fe III ) is an important process in the integrated electrobiofilm reduction method, and it has been regarded as a promising alternative method for removing NO x from industrial boiler flue gas. EDTA-Fe II -NO and EDTA-Fe III 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 II -NO and EDTA-Fe III 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 Alicycliphilus, Enterobacteriaceae , and Raoultella were the dominant genera (>25% each) during the process of EDTA-Fe II -NO reduction. Chryseobacterium had the ability to endure the shock loading of EDTA-Fe III , and the relative abundance of Chryseobacterium under abnormal operation conditions was up to 30.82%. Ochrobactrum 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 II -NO and EDTA-Fe III approached the same value (9 mmol·L -1 ).