Hidrodinamičke karakteristike pulzacionih ekstrakcionih kolona sa punjenjem

Abstract

This work presents an overview of the research related to the determination of hydrodynamic characteristics of pulsed packed extraction columns using different liquid-liquid two-phase systems. The following hydrodynamic characteristics are examined: flooding velocity, mean drop diameter of the dispersed phase, the dispersed-phase holdup, and an axial dispersion coefficient. In this paper, the effects of operating parameters (pulsation velocity, superficial velocities of the phases) on the flooding point data taken from the literature are analyzed. The experimental data taken from the literature indicate that the maximum throughput of extraction devices decreases with an increase in pulsation velocity and the flow rate of the phases. By comparing these experimental data for liquid-liquid two-phase systems presented in the literature, it has been concluded that the overall flooding velocity decreases with increasing the flow rate ratio of the phases. It has been determined that the Sauter mean drop diameter is significantly dependent on pulsation velocity and interfacial tension, and that it is not a function of flow rates of the phases. The dispersed-phase holdup has been shown to increase with increasing the flow rate ratio, reaching its maximum value at the flooding point, when small drops are formed. It has been concluded that the dispersed-phase holdup increases with an increase in the flow rate ratio. The authors have presented and analyzed some of the empirical correlations taken from the literature for flooding velocity, mean drop diameter, dispersed-phase holdup, and axial dispersion coefficient as functions of operating parameters, packing characteristics, and physical properties of liquid-liquid systems.