Abstract
Microbubble generation by a novel fluidic oscillator driven
approach is analyzed, with a view to identifying the key design
elements and their differences from standard approaches to
airlift loop bioreactor design. The microbubble generation
mechanism has been shown to achieve high mass transfer rates by
the decrease of the bubble diameter, by hydrodynamic
stabilization that avoids coalescence increasing the bubble
diameter, and by longer residence times offsetting slower
convection. The fluidic oscillator approach also decreases the
friction losses in pipe networks and in nozzles/diffusers due to
boundary layer disruption, so there is actually an energetic
consumption savings in using this approach over steady flow.
These dual advantages make the microbubble generation approach a
promising component of a novel airlift loop bioreactor whose
design is presented here. The equipment, control system for flow
and temperature, and the optimization of the nozzle bank for the
gas distribution system are presented.