title: Mixing and mass transfer in a pilot scale U-loop bioreactor.
abstract: A system capable of handling a large volumetric gas fraction while providing a high gas to liquid mass transfer is a necessity if the metanotrophic bacterium Methylococcus capsulatus is to be used in single cell protein (SCP) production. In this study, mixing time and mass transfer coefficients were determined in a 0.15 m3forced flow U-loop fermenter of a novel construction. The effect on the impeller drawn power when a gas was introduced into the system was also studied. Mixing time decreased and mass transfer increased with increasing volumetric liquid flow rate and specific power input. This happened also for a large volume fraction of the gas, which was shown to have only minor effect on the power drawn from the pump impeller. Very large mass transfer coefficients, considerably higher than those obtainable in an STR and previous tubular loop reactors, could be achieved in the U-loop fermenter equipped with static mixers at modest volumetric liquid and gas flow rates. Biotechnol. Bioeng. 2017;114: 344-354. © 2016 Wiley Periodicals, Inc.
authors: CAPEC-PROCESS Research Centre, Department of Chemical Biochemical Engineering, Technical University of Denmark, 2800 Lyngby, Denmark.|Unibio A/S, Odense, Denmark.
authors: Leander A H
authors: LA
authors: Petersen
authors: CHEC Research Centre, Department of Chemical and Biochemical Engineering, Technical University of Denmark, Lyngby, Denmark.
authors: John
authors: J
authors: Villadsen
authors: CAPEC-PROCESS Research Centre, Department of Chemical Biochemical Engineering, Technical University of Denmark, 2800 Lyngby, Denmark.
authors: Sten B
authors: SB
authors: Jørgensen
authors: CAPEC-PROCESS Research Centre, Department of Chemical Biochemical Engineering, Technical University of Denmark, 2800 Lyngby, Denmark.
authors: Krist V
authors: KV
authors: Gernaey
mesh_terms: D019149:Bioreactors; D004867:Equipment Design; D005285:Fermentation; D005740:Gases; D020618:Methylococcus / Q000378:metabolism; D008962:Models, Theoretical; D010865:Pilot Projects
chemical_list: D005740:Gases
keywords: SCP; U-loop; loop bioreactors; mass transfer; mixing; power input