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Continuously-stirred Anaerobic Digester to Convert Organic Wastes into Biogas: System Setup and Basic Operation
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Automatic process control in anaerobic digestion technology: A critical review
Duc Nguyen1, Venkataramana Gadhamshetty2, Saoharit Nitayavardhana3
1Department of Molecular Biosciences and Bioengineering, University of Hawai'i at Mānoa, 1955 East-West Road, Honolulu, HI 96822, USA.
Bioresource Technology
|July 8, 2015
Summary
Anaerobic digestion (AD) is a microbial process sensitive to disturbances. This review critically examines automatic control technologies for efficient AD process operation and monitoring at various scales.
Area of Science:
- Biotechnology and biochemical engineering
- Environmental science and engineering
- Microbial ecology
Background:
- Anaerobic digestion (AD) is a well-established technology utilizing microbial communities to break down organic matter.
- AD processes are susceptible to operational disruptions, necessitating effective monitoring and control strategies.
- Optimizing AD performance requires robust control systems to manage microbial consortia and substrate conversion.
Purpose of the Study:
- To provide a critical overview of automatic control technologies applicable to anaerobic digestion.
- To assess the suitability of various monitoring and control strategies for AD processes of different scales.
- To discuss the implementation challenges and benefits of advanced control systems in AD.
Main Methods:
- Review of existing literature on online monitoring and process control in anaerobic digestion.
- Analysis of different types of sensors (electrochemical, chromatographic, spectroscopic) for AD monitoring.
- Evaluation of control strategies ranging from feedback to advanced systems.
Main Results:
- A variety of sensors and control strategies can be implemented for AD process monitoring and control.
- The choice of technology depends on the scale of the AD plant and the desired level of automation.
- Centralized AD plants offer potential for advanced automatic control applications.
Conclusions:
- Implementing automatic control technologies is crucial for enhancing the efficiency and stability of anaerobic digestion.
- Further research and development are needed to optimize the integration of advanced instrumentation and control strategies.
- Automatic control systems can significantly improve the reliability and performance of AD processes across different scales.
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