MASS-TRANSFER AND BUBBLE-SIZE IN A BUBBLE-COLUMN UNDER PRESSURE

The influence of pressure on the gas hold-up in a bubble column is det ermined for a sodium sulphite solution in combination with the volumet ric mass transfer coefficient. Furthermore, for the same conditions th e bubble size is also estimated from photos. The results of these expe riments show that the interfacial area and the volumetric mass transfe r coefficient both increase with pressure, while for design purposes t he magnitude of the increase can be safely estimated from the increase in gas hold-up. Finally, the influence of pressure on the Sauter mean bubble size in a number of pure liquids (mono-ethylene glycol, n-hept ane and deionized water) is also studied and correlated with a new emp irical equation on the basis of photos in combination with literature results.