Experimental study on hold-up, characteristic and slip velocities in a horizontal pulsed sieve-plate column and uranium reactive extraction condition in aqueous phase

Abstract

The uranium extraction efficiency from sulfate leach liquor and the hydrodynamic behavior of the reactive extraction system was studied in the horizontal pulsed sieve-plated column. The effects of operating parameters and reactive condition were investigated. The obtained results showed that an increase in pulse intensity caused the decrease of dispersed phase hold-up and increase slip velocity. The slip velocity in the reactive uranium extraction situation was greater than that of the system without the reactive extraction due to the faster upward movement and more buoyancy of drops. The uranium extraction efficiency has a direct relationship with increasing pulse intensity and the dispersed phase flow rate, whereas has an indirect relationship with increasing continuous phase flow rate. Also, with comparison between experimental results and several empirical correlations for characteristic velocity, the Pratt model was chosen for prognostication of this parameter. The experimental results compared with the proposed correlations obtained from the previous studies demonstrated that the previous correlations have any reasonable accuracy to prognosticate the hold-up as well as the characteristic and slip velocities in this column. Therefore, the semi-empirical correlations were determined for prediction of hydrodynamic parameters as functions of the physical properties of systems and operating conditions. It can also be concluded that the horizontal pulsed sieve column is suitable for extraction of uranium from the sulfate liquor by Alamine 336 with extraction efficiency of approximately 99%. Therefore, it is a good alternative in radioactive processes, especially in places with height limitation.