Multiple electron acceptor-mediated sulfur autotrophic denitrification: Nitrogen source competition, long-term
Jiao-Jiao Wang1, Lian-Zeng-Ji Xu2, Bao-Cheng Huang2
1Key Laboratory of Microbial Technology for Industrial Pollution Control of Zhejiang Province, College of Environment, Zhejiang University of Technology, Hangzhou 310014, China; Laboratory of Water Pollution Remediation, School of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 311121, China.
Bioresource Technology
|March 8, 2021
Summary
Sulfur-driven autotrophic denitrification (SDAD) effectively removes nitrogen and sulfur from wastewater. Using multiple electron acceptors enhances system stability and performance, even with high pollutant loads.
Area of Science:
- Environmental Science
- Microbiology
- Water Treatment Engineering
Background:
- Sulfur-driven autotrophic denitrification (SDAD) is a viable method for treating wastewater with low carbon-to-nitrogen ratios and high sulfur content.
- Accumulated nitrite in SDAD systems can impede performance but also serves as a potential electron acceptor.
Purpose of the Study:
- To investigate the efficacy of single- and multiple-electron acceptor-mediated SDAD systems.
- To determine the optimal electron acceptors for nitrogen and sulfur removal in SDAD.
Main Methods:
- Batch assays were conducted to compare single- and multiple-electron acceptor systems.
- Continuous flow experiments were performed to evaluate system performance under high pollutant loads.
Main Results:
- Nitrite and nitrate were identified as preferential electron acceptors in single- and multiple-electron acceptor systems, respectively.
- Synchronous nitrogen and sulfur removal was achieved in the multiple-electron acceptor system.
- The system demonstrated resilience to high concentrations of sulfide (720 mg L⁻¹), nitrate (108 mg L⁻¹), and nitrite (64.8 mg L⁻¹).
- Microbial community analysis revealed a shift in predominant genera from Thiobacillus to unclassified_p_Firmicute and Syner-01.
Conclusions:
- SDAD systems utilizing multiple electron acceptors are effective for simultaneous nitrogen and sulfur removal.
- These systems exhibit robust performance and adaptability to challenging wastewater conditions.
- This research provides a foundation for optimizing SDAD applications in treating nitrogen- and sulfide-laden wastewaters.
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