Residence Time Distribution Model of Dual Phase Fluid Flow in the Mixer Settler

In this study, the residence time distribution of the fluid stream in a mixer settler was simulated in order to achieve the optimal extraction time and the best performance. The aqueous and organic phases were water and kerosene, respectively; and the salt tracer changes were recording continuously by using a conductivity meter. Initially, experiments were performed at different mixing times in the phase ratio of 1: 1. Then, results were analyzed applying Matlab software and Weller and N-Mixer models in RTDWEN software. Finally, for the mixing period of 5 min, the mean residence time was obtained 4.86 min by Matlab, and 6.44 and 6.62 min by RTDWEN, respectively for Weller and N-Mixer models. Furthermore, setting the mixing period at 5 min, the effect of mixer settler units was investigated by using N-Mixer model, and it was found that it was beneficial to increase the number of units, and set the residence time distribution close to extraction time at 6 min. It was also shown that under these conditions, the removed material from the mixer before the mean residence time was minimum, and both phases have an enough time for mixing and settling.