Gas Dispersion

Gas Hold Up

A good proportion of chemical reactions between gas and liquid occur in agitated tank reactor configurations. Radial turbines are often used to give a combination of shear and radial discharge patterns, with multiple turbines often required. A sparger ring for gas introduction below the bottom impeller is preferred over an injection tube.

Hydrodynamics and Mass transfer

Fully baffled tanks, often tall and narrow in configuration, provide the greatest residence time for the gas and effective number of stages. CFD modeling provides information such as gas hold up, interfacial area and mass transfer coefficient. It allows you to predict the former two while the k_La can be computed based on the local interfacial area properties and the turbulence energy dissipation.

Flooding Conditions

You can estimate the aeration number based on correlations using MixSim. Model the hydrodynamics based on a specified sparging flow rate. Use CFD to predict operating conditions, identify poor dispersion and modify the gas dispersion system.

Contours of mass transfer coefficient, k_La (0 - 10 s^-1)