Abstract
Aim: In this study, the hydrodynamic behavior and mass transfer characteristics of a cocurrent down flow contacting reactor (CDCR) were investigated for air-tap water and airfermentation broth systems.
Observation: As gas and liquid flow rates increased, the values of kLa and gas hold ups increased. The values of kLa measured in the air-fermentation broth system were all lower than those in the air-tap water system, but the values of gas hold up were higher.
Result: Bacillus amyloliquefaciens bacterial was grown in a medium of 10 g L-1 glucose and the specific growth rate, maximum dry cell concentration, and yield of biomass on glucose were determined to be 0.310 h-1, 5.0 g dry cell L-1, 0.500 g dry cell g-1 glucose, respectively.
Conclusion: The values of kLa and qO2, increased at active growth phase and then decreased with decreasing active cells.
Keywords: B. amyloliquefaciens, mass transfer, kLa, qO2, fermentation, matrix.
Graphical Abstract
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