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Updated: May 27, 2026
11:39
High-throughput Saccharification Assay for Lignocellulosic Materials
Published on: July 3, 2011
Design and evaluation of an optimal controller for simultaneous saccharification and fermentation process.
Ganti S Murthy1, David B Johnston, Kent D Rausch
1Biological and Ecological Engineering, Oregon State University, Corvallis, OR 97331-3906, USA. murthy@engr.orst.edu
Applied Biochemistry and Biotechnology
|November 26, 2011
Summary
An optimal controller was developed for the simultaneous saccharification and fermentation (SSF) process in corn ethanol production. This controller improves ethanol concentration and offers significant cost savings in dry grind plants.
Area of Science:
- Biochemical Engineering
- Process Control
- Renewable Energy
Background:
- Simultaneous saccharification and fermentation (SSF) is a critical step in dry grind corn ethanol production.
- Optimizing SSF is essential for improving process efficiency and economic viability.
Purpose of the Study:
- To develop an optimal controller for the SSF process using a validated model.
- To evaluate the controller's performance under various process disturbances.
Main Methods:
- Formulating the SSF process as a Bolza problem.
- Employing gradient descent methods for optimal controller development.
- Conducting validation experiments to assess controller performance.
Main Results:
- The optimal controller reduced peak glucose concentration.
- Similar ethanol yields were observed compared to baseline experiments.
- Improved final ethanol concentrations were achieved under temperature and pH disturbances.
- Estimated cost savings of up to $1 million annually due to reduced enzyme usage and cooling requirements.
Conclusions:
- Optimal control significantly enhances the SSF process performance in corn ethanol production.
- The developed controller demonstrates robustness against common process disturbances.
- Implementation of optimal control offers substantial economic benefits for dry grind ethanol plants.
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