Work

Dynamic mixing protocol for mixing enhancement in unbaffled bioreactor with eccentric bottom-mounted impeller

Year: 2025

Type: article

Abstract: The study introduces a novel mixing approach for industries requiring sterility, easy cleanability, and low shearing . It aims at an ultrapure mixing configuration comprising an unbaffled cylindrical vessel with an asymmetrically placed levitating impeller . However, that solution may be prone to forming a poorly mixed central vortex region worsening its overall mixing characteristics. To eliminate these adverse effects, a dynamic mixing protocol consisting of periodic changes in the impeller speed and direction is developed. Experiments conducted in a pilot-scale vessel (60L) confirm that this method eliminates the poorly mixed zone and reduces homogenization time by more than 50 % compared to a fixed-speed impeller. Additionally, numerical simulations reveal no excessive shearing due to speed and direction changes. It is shown that dynamic mixing protocol allows for significant improvement in vessel mixing characteristics while maintaining gentle handling of shear-sensitive materials.

Source: Chemical Engineering Science

DOI: 10.1016/j.ces.2025.121645

Authors: Ondřej Gebouský, Jan Haidl, Vojtěch Bílek, Martin Pivokonský

Institutions: Czech Academy of Sciences, Czech Academy of Sciences, Institute of Hydrology, University of Chemistry and Technology, Prague

Language: English

Topic: Fluid Dynamics and Mixing

Subfield: Biomedical Engineering

Field: Engineering

Domain: Physical Sciences

Open Access status: hybrid

Estimated APC paid: $4,050

Funders: Ministerstvo Školství, Mládeže a Tělovýchovy, Grantová Agentura České Republiky, Akademie Věd České Republiky