Autotrophic denitrification using Fe(II) as an electron donor: A novel prospective denitrification process
Yaning Wang1, Shuang Ren1, Peng Wang1
1College of Environmental and Municipal Engineering, Lanzhou Jiaotong University, Lanzhou 730070, China; Key laboratory of Yellow River Water Environment in Gansu Province, Lanzhou 730070, China.
The Science of the Total Environment
|October 28, 2022
Summary
The nitrate-dependent ferrous oxidation (NDFO) process offers a novel nitrogen removal pathway for low carbon to nitrogen ratio wastewater. This review explores NDFO microorganisms, influencing factors, and proposes electron transfer mechanisms for enhanced wastewater treatment.
Area of Science:
- Environmental Science
- Microbiology
- Wastewater Treatment Engineering
Background:
- Nitrate-dependent ferrous oxidation (NDFO) is a newly identified nitrogen loss pathway.
- NDFO is gaining attention for treating low carbon to nitrogen ratio (C/N) wastewater.
Purpose of the Study:
- To provide a comprehensive overview of the NDFO process.
- To summarize functional microorganisms, influencing factors, and electron transfer mechanisms.
- To discuss challenges and future research directions for NDFO application in nitrogen removal.
Main Methods:
- Literature review of existing studies on NDFO.
- Analysis of microbial communities involved in NDFO.
- Discussion of chemical and enzymatic electron transfer pathways.
- Evaluation of external factors affecting NDFO performance.
- Review of Fe(III) mineral product impacts and crusting prevention.
Main Results:
- Identified key functional microorganisms in NDFO.
- Discussed the impact of pH, Fe(II)/N ratio, organic carbon, and chelating agents on NDFO.
- Described the chemical Fe(II)-oxidizing nitrite-reducing pathway (NDFOchem).
- Proposed a three-stage electron transfer pathway for low C/N wastewater.
- Revisited the impact of Fe(III) mineral products and summarized crusting prevention strategies.
Conclusions:
- NDFO is a promising process for nitrogen removal in low C/N wastewater.
- Understanding electron transfer mechanisms and microbial roles is crucial for process optimization.
- Further research is needed to address challenges and advance NDFO technology.
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