Basics of gas flow modulation applied to bubble columns

Bubble columns are industrial equipment used for promoting the contact between the gas and the liquid phase. In the column, the gas phase rises in form of bubbles in a pool of liquid. The fraction of the column’s volume occupied by the gas is called gas holdup. Bubble column applications include bioreactors, production of food and beverage as well as of crucial chemicals. The Axial Dispersion Model is the most accepted model for describing the gas flow in bubble columns. In this model, all phenomena deviating from plug-flow conditions are combined and indicated as dispersion. Knowledge of the axial dispersion coefficient is crucial for designing bubble column reactors. This study provides a new non-invasive approach for measuring axial gas dispersion coefficients in bubble column reactors and the application of the new approach at different operating conditions.