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Title: CFD evaluation of hydrophobic feedstock bench‐scale fermenters for efficient high agitation volumetric mass transfer
Abstract A new biomanufacturing platform combining intracellular metabolic engineering of the oleaginous yeastYarrowia lipolyticaand extracellular bioreaction engineering provides efficient bioconversion of plant oils/animal fats into high‐value products. However, predicting the hydrodynamics and mass transfer parameters is difficult due to the high agitation and sparging required to create dispersed oil droplets in an aqueous medium for efficient yeast fermentation. In the current study, commercial computational fluid dynamic (CFD) solver Ansys CFX coupled with the MUSIG model first predicts two‐phase system (oil/water and air/water) mixing dynamics and their particle size distributions. Then, a three‐phase model (oil, air, and water) utilizing dispersed air bubbles and a polydispersed oil phase was implemented to explore fermenter mixing, gas dispersion efficiency, and volumetric mass transfer coefficient estimations (kLa). The study analyzed the effect of the impeller type, agitation speed, and power input on the tank's flow field and revealed that upward‐pumping pitched blade impellers (PBI) in the top two positions (compared to Rushton‐type) provided advantageous oil phase homogeneity and similar estimatedkLavalues with reduced power. These results show good agreement with the experimental mixing andkLadata.  more » « less
Award ID(s):
1911480 2100075
PAR ID:
10497583
Author(s) / Creator(s):
; ; ;
Editor(s):
Yongjin J. Zhou
Publisher / Repository:
Wiley
Date Published:
Journal Name:
Biotechnology Journal
Volume:
19
Issue:
2
ISSN:
1860-6768
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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