Gas-Liquid Mixing or Dispersion

This is another common processing operation, usually for chemical reactions and neutralizations or other mass transfer functions. Pilot plant or research data are.needed to accomplish a proper design or scale-up. Therefore, generalizations can only assist in alerting the designer as to what type of mixing system to expect. 

This dispersion of the gas passes through several stages depending on the gas feed rate to the underside of the impeller and the horsepower to the impeller, varying from inadequate dispersion at low flow to total gas bubble dispersion throughout the vessel. The open, without disk, radial flow type impeller is the preferred dispersing unit because it requires lower horsepower than the axial flow impeller. The impeller determines the bubble size and interfacial area. 

The gas dispersion ring or sparger can be a special design with holes or a single pipe entering the underside of the impeller, and there will be very little differences in mass transfer performance. References [25] and [29] provide valuable detail for considering design for gas dispersion/ mass transfer. 

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