Abstract
Mixing time (θ) was measured in a 45 or 60 1 working liquid volume external-circulation-loop airlift (ECL-AL) fermentor, and in a geometrically similar 6 1 prototype, both equipped with perforated-plate spargers (1 mm dia. holes). Carboxymethylcellulose solutions were used to simulate the rheological behaviour non-Newtonian fermentation broths. The specific mixing time (θ/ V) is shown to be highly dependent on the dispersion height and gas superficial velocity in the riser section, as well as on the riser diameter and the effective viscosity of the liquid phase. In the range studied (0.111⩽ A D / A R ⩽0.46), the downcomer-to-riser cross-sectional-area ratio has a relatively minor effect on θ/ V. The superficial velocity of the circulating liquid in the riser ( u LR ) was also measured. The results have been combined with those of a previous investigation, by Popovic and Robinson, to better elucidiate the effect of dispersion height on the rate of liquid circulation. A modified correlation of u LR is presented and discussed.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
