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Continuously-stirred Anaerobic Digester to Convert Organic Wastes into Biogas: System Setup and Basic Operation
Published on: July 13, 2012
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Methane production from food waste using a feedback control strategy in a sequencing batch reactor
U E Jiménez-Ocampo1, A Vargas1, I Moreno-Andrade1
1Laboratory for Research on Advanced Processes for Water Treatment, Unidad Académica Juriquilla, Instituto de Ingeniería, Universidad Nacional Autónoma de México, Blvd. Juriquilla 3001, 76230 Querétaro, México
Summary
A new feedback control strategy optimizes sequencing batch reactor operation using biogas flow. This method enhances methane and energy production by controlling reaction phase duration, boosting system efficiency.
Area of Science:
- Environmental Engineering
- Biotechnology
- Chemical Engineering
Background:
- Sequencing batch reactors (SBRs) are widely used for wastewater treatment and biogas production.
- Optimizing SBR operation is crucial for maximizing energy recovery and treatment efficiency.
- Current SBR operation often lacks dynamic control, leading to suboptimal performance.
Purpose of the Study:
- To evaluate a feedback control strategy for SBR operation based on online biogas flow measurements.
- To enhance methane production rate and overall energy output from SBRs.
- To simplify SBR control by utilizing readily available sensor data.
Main Methods:
- Implemented a depletion-time control strategy for the reaction phase of SBRs.
- Utilized online biogas flow rate measurements to determine the end of the reaction phase.
- Compared performance against conventional anaerobic digestion (AD) without a control strategy.
Main Results:
- Achieved a maximum methane production rate of 1.22 L CH4/d and an average productivity of 0.73 ± 0.3 L CH4/d.
- Increased methane and energy production by 10.4–43.8% in 80% of evaluated cycles.
- Reaction phase duration varied from 1.2 to 6 days with hydraulic retention times from 6 to 30 days.
Conclusions:
- The feedback control strategy effectively maximizes methane production rate and energy output in SBRs.
- The depletion-time control is easy to implement, requiring no complex calculations and using standard biogas flow sensors.
- This approach offers a significant improvement over conventional AD operations for energy recovery.
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