(155c) A Model for Gas-Liquid Contact in Stirred Vessels

Gas-liquid contact in stirred tanks received great attention due to their wide industrial applications. Parameters such as power consumption, bubble size, bubble hold-up and volumetric mass transfer coefficients as a function of stirrer speed and gas flow rate were experimentally measured and correlations useful for design were developed. There is growing need to rationalize the vast and wide variety of information available in the literature through application of principles of multiphase flow in stirred tanks. Experimental observations on a gassed stirred tank are presented and analyzed through model based equations. Liquid circulation generated by rotating impeller appears to counter the liquid circulation generated by the flowing gas. The net liquid circulation defines the gas hold-up and power consumption.