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Development of Sulfidogenic Sludge from Marine Sediments and Trichloroethylene Reduction in an Upflow Anaerobic Sludge Blanket Reactor
Published on: October 15, 2015
Enhanced sulfate reduction with acidogenic sulfate-reducing bacteria
Aijie Wang1, Nanqi Ren, Xu Wang
1School of Municipal & Environmental Engineering, Harbin Institute of Technology, P.O. Box 2614, 202 Haihe Road, Harbin 150090, China.
Journal of Hazardous Materials
|December 21, 2007
Summary
Optimizing the chemical oxygen demand to sulfate ratio is key for effective sulfate reduction in wastewater. A critical ratio of 2.7 supports high sulfate removal rates by sulfate-reducing bacteria.
Area of Science:
- Environmental microbiology
- Biotechnology
- Wastewater treatment
Background:
- Sulfate reduction is crucial for treating sulfate-laden industrial wastewater.
- Molasses wastewater offers a viable carbon source for microbial sulfate removal.
- Optimizing reactor conditions is essential for efficient sulfate reduction.
Purpose of the Study:
- To investigate sulfate reduction efficiency in an acidogenic reactor using molasses wastewater.
- To determine the critical chemical oxygen demand to sulfate (COD/SO4(2-)) ratios for optimal performance.
- To understand the microbial metabolism involved in COD and sulfate degradation.
Main Methods:
- Continuous flow acidogenic reactor operation.
- Varying chemical oxygen demand/sulfate (COD/SO4(2-)) ratios.
- Analysis of microbial metabolism, including hydrogen and volatile fatty acid consumption.
Main Results:
- A critical COD/SO4(2-) ratio of 2.7 was identified for efficient sulfate removal (>94.6%).
- At this ratio, neither COD nor sulfate were in excess, indicating balanced microbial activity.
- An acetic-type microbial metabolism was established, with sulfate-reducing bacteria (SRB) consuming key intermediates.
- A lower critical ratio of 1.6 was observed with an enriched anaerobic SRB (ASRB) population.
Conclusions:
- The critical COD/SO4(2-) ratio significantly impacts sulfate reduction efficiency.
- Balanced substrate supply (COD and sulfate) promotes effective microbial sulfate removal.
- Enriched ASRB populations can enhance sulfate treatment capabilities even with limited COD.
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