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Power Input Measurements in Stirred Bioreactors at Laboratory Scale
Published on: May 16, 2018
Modelling mass transfer and agitator performance in multiturbine fermentors
1Bristol-Myers Company, Industrial Division, P.O. Box 4755, Syracuse, New York 13221-4755.
Biotechnology and Bioengineering
|July 1, 1987
Summary
This study presents a mathematical model to analyze agitator performance and mass transfer in large fermentors. The model optimizes individual turbines and mixing cells, determining dissolved oxygen profiles and mass transfer coefficients.
Area of Science:
- Biochemical Engineering
- Chemical Process Engineering
Background:
- Optimizing mass transfer and dissolved oxygen is crucial for large-scale fermentation.
- Existing models often lack specificity for multiturbine systems.
Purpose of the Study:
- To develop a mathematical methodology for analyzing agitator performance and mass transfer in large multiturbine fermentors.
- To determine axial dissolved oxygen profiles based on agitation-aeration characteristics.
Main Methods:
- A stagewise modeling approach dividing the fermentor into discrete mixing cells.
- Individual optimization of each turbine and mixing cell.
- Determination of mass transfer coefficients using limited dissolved oxygen data.
Main Results:
- The model allows for individual optimization of turbines and mixing cells.
- It enables determination of mass transfer coefficients for each turbine.
- Simulations show the impact of operating variables and agitator design on dissolved oxygen profiles.
Conclusions:
- The stagewise model provides a framework for analyzing and optimizing multiturbine fermentor performance.
- It can be used to test and adapt single turbine correlations for multiturbine systems.
- The methodology aids in understanding and controlling dissolved oxygen levels in large-scale bioprocesses.
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