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Updated: Jul 3, 2026
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A Novel Bioreactor for High Density Cultivation of Diverse Microbial Communities
Published on: December 25, 2015
Hydrodynamics and mixing in a multiple air-lift loop reactor
W A Bakker1, H J van Can, J Tramper
1Wageningen Agricultural University, Department of Food Science, Food and Bioprocess Engineering Group, Wageningen, The Netherlands.
Biotechnology and Bioengineering
|October 1, 1993
Summary
A novel multiple air-lift loop (MAL) reactor was developed to mimic aerated plug-flow fermentors. Its hydrodynamics and mixing were comparable to conventional designs, showing potential for improved bioprocessing.
Area of Science:
- Biochemical Engineering
- Chemical Reactor Design
Background:
- Optimizing bioreactor design is crucial for efficient bioprocessing.
- Aerated plug-flow fermentors offer advantages in cell culture and fermentation.
- Existing internal-loop reactors have limitations in flow dynamics.
Purpose of the Study:
- Introduce a novel multiple air-lift loop (MAL) reactor.
- Approximate the hydrodynamics of an aerated plug-flow fermentor.
- Evaluate the mixing, liquid velocity, and gas hold-up of the MAL reactor.
Main Methods:
- Constructed a novel multiple air-lift loop (MAL) reactor.
- Measured hydrodynamics (mixing, liquid velocity, gas hold-up) as a function of gas flow rate.
- Compared MAL reactor performance to a conventional internal-loop reactor.
- Developed a two-phase, drift-flux model for the MAL reactor's second compartment.
Main Results:
- Frictional losses were independent of reactor bottom geometry.
- Frictional losses increased with gas flow rate due to stationary gas bubbles.
- Hydrodynamics and mixing in the second MAL compartment were comparable to conventional internal-loop reactors.
Conclusions:
- The developed MAL reactor approximates aerated plug-flow fermentor characteristics.
- MAL reactor hydrodynamics are comparable to conventional internal-loop reactors.
- The MAL reactor shows promise for bioprocessing applications requiring plug-flow characteristics.
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