Experimental Investigation of Flooding and Drop Size in a Kuhni Extraction Column

In this work, the hydrodynamic behavior of a Kuhni extraction column has been investigatedexperimentally. The experiments were carried out in the absence of mass transfer for two differentstandard chemical systems. In the experiments operating variables including agitation speed, flow rateof both liquid phases and interfacial tension have been studied. Sauter-mean drop diameter, floodingvelocity and holdup at flooding have been measured in the Kuhni column. The results showed thatSauter-mean diameter are strongly affected by agitation speed and interfacial tension whereas theeffects of continuous phase and dispersed phase flow rates are negligible. Two rigorous empiricalcorrelations are proposed for predicting flooding velocities and Sauter-mean drop diameterwith meandeviation of 5.7% and 7.2%, respectively. The mean drop size correlation is a function of columngeometry, operating conditions and physical properties of liquid systems. Good agreement betweenpredictions and experiments is found for all operating conditions investigated.