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Electrochemically and Bioelectrochemically Induced Ammonium Recovery
Published on: January 22, 2015
Hydrogen-dependent denitrification in a two-reactor bio-electrochemical system
S Szekeres1, I Kiss, T T Bejerano
1Department of Environmental Hydrology and Microbiology, Jacob Blaustein Institute for Desert Research, Ben-Gurion University of the Negev, Sede Boqer 84990, Israel.
Water Research
|March 7, 2001
Summary
This study presents a novel autotrophic biological process for removing nitrate from drinking water using an electrochemical cell and a bioreactor. The system achieved high denitrification rates and demonstrated stability over a year of operation.
Area of Science:
- Environmental Science
- Water Treatment Technologies
- Applied Microbiology
Background:
- Nitrate contamination in drinking water poses significant health risks.
- Conventional water treatment methods for nitrate removal can be costly and inefficient.
- Autotrophic biological denitrification offers a sustainable alternative.
Purpose of the Study:
- To develop and evaluate an autotrophic biological process for treating nitrate-contaminated drinking water.
- To optimize the process by investigating the effects of water velocity and current intensity.
- To assess the system's stability and efficiency in nitrate and nitrite removal.
Main Methods:
- A two-step system combining an electrochemical cell for hydrogen enrichment and a packed-bed bioreactor.
- Utilized granulated activated carbon as the bioreactor medium with upward continuous flow.
- Operated the system for one year, varying water velocities and current intensities.
Main Results:
- Achieved high denitrification rates of up to 0.25 kg N m-3 d-1 at a hydraulic residence time of 1 hour.
- The system demonstrated stable performance throughout the one-year operation.
- Low nitrite concentrations were observed in the effluent, even with high influent nitrate levels.
Conclusions:
- The developed autotrophic biological process is effective and stable for nitrate removal from drinking water.
- The system offers a promising sustainable solution for nitrate-contaminated water treatment.
- Further optimization could enhance efficiency and applicability in various water conditions.
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