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Updated: Jul 3, 2026
05:21
Operation of Laboratory Photobioreactors with Online Growth Measurements and Customizable Light Regimes
Published on: October 28, 2021
High-density algal photobioreactors using light-emitting diodes.
1Department of Chemical Engineering, University of Michigan, Ann Arbor, Michigan 48109.
Biotechnology and Bioengineering
|November 20, 1994
Summary
Developing a novel photobioreactor (PBR) using light-emitting diodes (LEDs) enabled high-density algal cultures. This breakthrough supports efficient algal biotechnology with rapid growth and high oxygen production.
Area of Science:
- Biotechnology
- Algal Cultivation
- Photobioreactor Design
Background:
- High-density algal cultures are crucial for biotechnology but limited by photobioreactor (PBR) technology.
- Advancements in light-emitting diode (LED) technology offer new possibilities for PBR development.
Purpose of the Study:
- To design and develop a small-scale, LED-based PBR for high-density algal cultivation.
- To determine the gas mass transfer and light-intensity requirements for optimal algal growth using monochromatic red LED light.
Main Methods:
- Calculated theoretical gas mass transfer and light-intensity needs for high-density cultures.
- Designed a prototype PBR utilizing 680 nm monochromatic red LED light.
- Employed on-line ultrafiltration for continuous medium refreshment.
Main Results:
- Achieved algal cell concentrations exceeding 2 x 10^9 cells/mL (6.6% v/v).
- Demonstrated rapid cell doubling times as low as 12 hours.
- Obtained high oxygen production rates of up to 10 mmol oxygen/L culture/h.
Conclusions:
- The developed LED-based PBR effectively supports high-density algal cultivation.
- The system demonstrates significant improvements in cell concentration, growth rate, and oxygen production.
- This technology advances the potential for large-scale algal biotechnology applications.
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