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Software sensor design considering oscillating conditions as present in industrial scale fed-batch cultivations
V Lyubenova1, S Junne, M Ignatova
1Institute of System Engineering and Robotics, Bulgarian Academy of Sciences, Acad. G. Bontchev str. Bl. 2, PO. Box 79, Sofia, Bulgaria. v_lyubenova@iser.bas.bg
Biotechnology and Bioengineering
|February 26, 2013
Summary
This study introduces a novel software sensor system for real-time monitoring of microbial growth and product synthesis in bioreactors. The method enhances understanding of industrial fed-batch cultivations under dynamic conditions.
Area of Science:
- Biotechnology
- Biochemical Engineering
- Process Control
Background:
- Industrial bioreactors exhibit inhomogeneous dynamics, complicating real-time process monitoring.
- Accurate observation of microbial growth and product synthesis under oscillating substrate availability is crucial for optimizing fed-batch cultivations.
- Existing methods lack the capability for on-line kinetic monitoring under industrially relevant conditions.
Purpose of the Study:
- To develop and validate a novel software sensor (SS) system for on-line kinetic monitoring of bioreactor processes.
- To simulate microbial growth and product synthesis under oscillating substrate availability, mimicking industrial fed-batch conditions.
- To improve the understanding and control of inhomogeneous dynamics in large-scale bioreactors.
Main Methods:
- A cascade-structured software sensor (SS) system was designed for kinetic monitoring.
- Process kinetics were simulated using models incorporating time-varying yield coefficients.
- A linear transformation with a logarithmic function was employed for the SS design of unmeasured variables.
- A tuning procedure was proposed, allowing calculation of optimal parameters for system stability.
Main Results:
- The proposed SS system effectively simulates process kinetics with time-varying yield coefficients.
- The SS design for unmeasured variables, utilizing a logarithmic transformation, proved effective.
- The tuning procedure enabled the calculation of optimal parameters, ensuring monitoring system stability.
- Experimental validation using Bacillus subtilis demonstrated the approach's effectiveness in mimicking industrial conditions.
Conclusions:
- The developed software sensor system provides a viable method for on-line kinetic monitoring in bioreactors.
- This approach enhances the study of inhomogeneous dynamics in industrial-scale fed-batch cultivations.
- The method offers improved insights into microbial processes under oscillating substrate availability, crucial for process optimization.
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