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A Novel Bioreactor for High Density Cultivation of Diverse Microbial Communities
Published on: December 25, 2015
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Bed-immersion-ratio variation as an efficient strategy to regulate denitrification efficiency directionally in
Guijiao Zhang1, Hao-Ran Xu1, Wenwei Liao1
1State Key Laboratory of Urban Water Resources and Environment, School of Civil and Environmental Engineering, Harbin Institute of Technology Shenzhen, Shenzhen, 518055, China.
Water Research
|December 13, 2024
Summary
We developed a novel method to control nitrate removal efficiency in sulfur packed-bed reactors (S0PBR) by adjusting the bed-immersion-ratio (BIR). This approach ensures stable nitrate effluent and reduces sulfur consumption, offering an efficient and economical solution.
Area of Science:
- Environmental Engineering
- Water Treatment Technologies
- Bioreactor Design
Background:
- Autotrophic denitrification using sulfur packed-bed reactors (S0PBR) is common for municipal wastewater treatment.
- Fixed sulfur volumes limit adaptability to fluctuating nitrate levels, causing effluent issues and waste.
- A need exists for dynamic control of denitrification efficiency in S0PBR.
Purpose of the Study:
- To propose and validate a novel method for regulating nitrate removal efficiency (NRE) in S0PBR.
- To investigate the impact of adjusting the bed-immersion-ratio (BIR) on NRE.
- To develop a kinetic model for nitrate reduction under varying BIR.
Main Methods:
- Implemented a novel approach by adjusting the bed-immersion-ratio (BIR) in S0PBR.
- Correlated BIR adjustments with nitrate removal efficiency (NRE) and actual hydraulic retention time (aHRT).
- Developed and validated a kinetic model integrating exposure and immersion parameters (Rj=(Cin-01/2-Ce1/2)Q2.54AHt-0.65).
Main Results:
- Nitrate removal efficiency (NRE) was effectively controlled by adjusting the bed-immersion-ratio (BIR).
- Maximum NRE was achieved at BIR of 1.00, with a minimum observed at BIR of 0.00.
- A strong correlation between actual hydraulic retention time (aHRT) and BIR was identified.
- The developed kinetic model accurately described nitrate reduction kinetics under varying BIR.
- BIR variation led to more stable effluent nitrate levels and reduced sulfur consumption (7.8%–31.6%).
Conclusions:
- Adjusting the bed-immersion-ratio (BIR) offers a viable strategy for dynamically controlling nitrate removal efficiency in S0PBR.
- The developed kinetic model provides a predictive tool for optimizing S0PBR operation under fluctuating nitrate loads.
- This novel approach enhances treatment stability, reduces operational costs, and minimizes sulfur waste.
Keywords:
Bed-immersion-ratioKinetic modelNitrate removal efficiencyRegulationSulfur packed-bed reactorsMore Related Videos
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