Modeling of Hydrodynamic parameters of rotating disc contactors (RDCs) using response surface methodology: holdup and drop size

Abstract

Abstract In this study, the behavior of hydrodynamic parameters was investigated in agitated columns including Asymmetric rotating disc contactor (ARDC), Perforated rotating disc contactor (PRDC), Oldshue-Rushton column (ORC), and Kuhni for three different systems such as butanol-water, n-butyl acetate-water and toluene-water. The effects of various parameters including rotor speed (rpm), dispersed and continuous phase velocities, and interfacial parameters were studied on the dispersed phase holdup and Sauter mean drop diameter. The results showed that the enhancement of rotor speed, and dispersed and continuous phase velocities would enhance the dispersed phased holdup. Among these, PRDC shows the least enhancement of dispersed phase holdup compared to the other three columns. The investigation of Sauter mean drop diameter changes in the columns showed that the droplet size decreases sharply as the rotor speed increases, which this decrease of droplet size is greater in ORC and Kuhni columns than in the other two columns. The results also show that by increasing dispersed phase velocity in the four columns, the droplet size in ORC column is larger than the columns, However, by increasing continuous phase velocity, subtle changes in droplet size are observed, Based on the experimental data, new correlations have been presented to predict Sauter mean drop diameter and dispersed phase holdup for agitated columns by the analysis of the variance (ANOVA). The coefficient of determination (R2) was obtained 0.9612 and 0.9495 for Sauter mean drop diameter and dispersed phase holdup, respectively, indicating a good correlation between the predicted and observed and values of the models.