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Updated: Jul 16, 2026
11:31
Continuously-stirred Anaerobic Digester to Convert Organic Wastes into Biogas: System Setup and Basic Operation
Published on: July 13, 2012
A mathematical model for a hybrid anaerobic reactor
V Saravanan1, T R Sreekrishnan
1Department of Biochemical Engineering and Biotechnology, Indian Institute of Technology Delhi, New Delhi 110 016, India.
Journal of Environmental Management
|March 21, 2007
Summary
A mathematical model for hybrid anaerobic reactors (HARs) was developed, considering glucose fermentation and bacterial distribution. A layered bacterial structure within granules accurately predicted reactor performance and treatment efficiency.
Area of Science:
- Biotechnology
- Environmental Engineering
- Chemical Engineering
Background:
- Hybrid anaerobic reactors (HARs) are crucial for wastewater treatment.
- Understanding microbial community structure within granules is key to optimizing HAR performance.
- Glucose fermentation into methane is a primary process in anaerobic digestion.
Purpose of the Study:
- To develop a comprehensive mathematical model for HARs.
- To investigate the role of spatial distribution of anaerobic bacteria within granules.
- To predict substrate and product concentration profiles in HARs.
Main Methods:
- Developed a multi-component mathematical model including biofilm, bed fluidization, and reactor dynamics.
- Incorporated stoichiometry of glucose fermentation and inhibition kinetics (product and pH).
- Simulated the model with both layered and homogeneous bacterial distributions within granules.
Main Results:
- The spatial distribution of anaerobic bacteria within granules significantly impacts conversion efficiency.
- Model simulations assuming a 3-layered bacterial structure closely matched experimental data.
- The developed model accurately predicts substrate and product concentrations along the reactor height.
Conclusions:
- A layered structure of anaerobic bacteria within granules is vital for efficient glucose conversion in HARs.
- The developed mathematical model provides a reliable tool for predicting HAR performance.
- This study enhances the understanding of microbial ecology in anaerobic digestion systems.
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