Mixing in the mechanically agitated bioreactor: ‘a matter of being stirred, not shaken’
Document Type
Article
Publication Date
1-1-2007
Abstract
Stirred vessel bioreactors are often equipped with the standard 6-blade disc turbine without much thought for process specifications. Variations in the system parameters can in fact give rise to significant differences in mixing requirement, and failure to operate at the right conditions can result in undesirable outcomes. Biological systems are sensitive to bioreactor hydrodynamics since it directly affects transport processes at the molecular level. In addition, extracellular products and filamentous microbes contribute to drastic changes in the broth characteristics over the course of fermentation, that would in turn alter the mixing needs. Poor mixing or over mixing can both have adverse effects on product quality, but inefficient equipment design leading to excessive energy requirement often goes unnoticed if there are no apparent effects on the product. This paper summarizes the basic considerations to be made for given mixing duties so as to enable operations in a calculated rather than random manner.
Keywords
Impeller, Mixing Power, Multiphase Mixing and Rheological Effects, Stirred Vessel
Divisions
fac_eng
Publication Title
Journal of the Institution of Engineers, Malaysia
Volume
68
Issue
3
Publisher
The Institution of Engineers Malaysia