Promoting the nitrogen removal of anammox process by Fe-C micro-electrolysis

Fei Xie; Xiao Ma; Bowei Zhao; Ying Cui; Xiao Zhang; Xiuping Yue

doi:10.1016/j.biortech.2019.122429

Promoting the nitrogen removal of anammox process by Fe-C micro-electrolysis

Bioresour Technol. 2020 Feb:297:122429. doi: 10.1016/j.biortech.2019.122429. Epub 2019 Nov 14.

Authors

Fei Xie¹, Xiao Ma¹, Bowei Zhao¹, Ying Cui¹, Xiao Zhang¹, Xiuping Yue²

Affiliations

¹ College of Environmental Science and Engineering, Taiyuan University of Technology, Taiyuan 030024, PR China.
² College of Environmental Science and Engineering, Taiyuan University of Technology, Taiyuan 030024, PR China. Electronic address: yuexiuping@tyut.edu.cn.

PMID: 31791919
DOI: 10.1016/j.biortech.2019.122429

Abstract

In this study, a process that combines iron-carbon micro-electrolysis (IC-ME) with the anammox process was successfully established for promoting nitrogen removal, especially the removal of nitrate by-product. Compared with the conventional anammox process, the average total nitrogen removal efficiency of the combined system increased from 64.6% to 90.2% and 83.8% when the system was effectively operated for 4 days (Phase 2) and 13 days (Phase 3), respectively. In this combined system, IC-ME played a dual role: 1) converting the nitrate to ammonia as the nitrogen substrate for further degradation, and 2) producing Fe²⁺, Fe³⁺ and H₂ for the nitrogen removal processes of NH₄⁺ oxidation with Fe³⁺ reduction (Feammox), nitrate-dependent Fe²⁺ oxidation (NDFO), and denitrification, in addition to the anammox process. Microbial analysis using 16S rRNA high-throughput sequencing revealed Candidatus Kuenenia and Candidatus Brocadia as the major anammox genera, accounting for 1.01% and 0.15%, respectively.

Keywords: Anammox; By-product; Denitrification; Feammox; Micro-electrolysis.

MeSH terms

Bioreactors
Denitrification*
Electrolysis
Nitrogen*
Oxidation-Reduction
RNA, Ribosomal, 16S

Substances

RNA, Ribosomal, 16S
Nitrogen