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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
Autotrophic denitrification with sulphide in a sequencing batch reactor
C Fajardo1, A Mosquera-Corral, J L Campos
1Department of Chemical Engineering, School of Engineering, University of Santiago de Compostela, Rúa Lope Gómez de Marzoa, 15782 Santiago de Compostela, Spain. mariadelcarmen.fajardo@usc.es
Journal of Environmental Management
|June 19, 2012
Summary
This study shows that sequencing batch reactors can effectively remove sulphide and nitrate using autotrophic denitrification. The process achieved 100% sulphide removal and 67% nitrate removal, with Thiobacillus bacteria playing a key role.
Area of Science:
- Environmental microbiology
- Biotechnology
- Wastewater treatment
Background:
- Sulphide and nitrate pollution pose significant environmental challenges.
- Autotrophic denitrification offers a sustainable approach to nitrogen removal.
Purpose of the Study:
- To investigate the simultaneous removal of sulphide and nitrate using autotrophic denitrification in a sequencing batch reactor (SBR).
- To evaluate the impact of varying sulphide loading rates and pH on removal efficiencies.
Main Methods:
- Utilized a sequencing batch reactor (SBR) for autotrophic denitrification.
- Gradually increased sulphide loading rates while maintaining constant nitrogen loading rates.
- Monitored sulphide and nitrate removal efficiencies and analyzed the influence of pH.
Main Results:
- Achieved 100% sulphide removal and 67% nitrate removal efficiencies.
- Demonstrated the feasibility of autotrophic denitrification in an SBR.
- Identified pH values above 9.0 as detrimental to sulphide oxidation efficiency (reduced to 11.3%).
- Identified Thiobacillus genus as the dominant bacteria in the sludge.
Conclusions:
- Autotrophic denitrification in an SBR is a viable method for simultaneous sulphide and nitrate removal.
- Process efficiency is highly sensitive to pH, with optimal performance below 9.0.
- Thiobacillus bacteria are crucial for the success of this biological process.
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