title: Enhancement of oxygen transfer in highly viscous non-newtonian fermentation broths.
abstract: The influence of short draft tubes covered by perforated plates on gas-liquid mass transfer was examined in external-loop airlift bioreactors. The volumetric mass transfer coefficients in a model external-loop airlift bioreactor were measured with water and non-Newtonian media. It was found that introduction of draft tubes covered with perforated plates in the riser significantly improved the mass transfer rate, particularly in higher viscous non-Newtonian fermentation media. The enhancement of mass transfer rate might be due mainly to an increase in bubble coalescence and redispersion.
authors.affiliation: Biochemical Engineering Research Center, Department of Applied Chemistry, Toyo University, Kawagoe, Saitama 350, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Kawase
authors.forename: M
authors.initials: M
authors.lastname: Tsujimura