Characterizing the effect of impeller design in plant cell fermentations using CFD modeling

Area of Science:

• Biotechnology
• Biochemical Engineering
• Plant Cell Culture

Background:

• Plant cell cultures in conventional bioreactors often show reduced productivity compared to shake flasks.
• This decrease is likely due to a mismatch in mass transfer needs and cell viability.
• Traditional bioreactor design relies on trial-and-error methods.

Purpose of the Study:

• To rationally select a suitable impeller for Viola odorata cell suspension culture.
• To utilize computational fluid dynamics (CFD) for optimizing bioreactor design.
• To investigate impeller impact on critical process parameters.

Main Methods:

• A two-phase CFD model was developed to simulate non-Newtonian fluid dynamics.
• Euler-Euler approach and a dispersed k-ε turbulence model were used.
• Simulations compared setric, Rushton, and marine impeller designs.
• The numerical model was validated against experimental volumetric mass transfer coefficients.

Main Results:

• The CFD model predicted mixing, oxygen mass transfer, and shear stress for each impeller.
• The setric impeller demonstrated superior performance for Viola odorata cell cultivation.
• It provided a low-shear environment and higher cell-lift capabilities.

Conclusions:

• The setric impeller is a suitable choice for high cell-density Viola odorata cultivation.
• CFD modeling offers a rational approach to bioreactor impeller selection.
• Optimized impeller design can enhance biomass productivity in plant cell cultures.