Unified new correlation for prediction of dispersed phase holdup in agitated extraction columns

• Published in: Separation and purification technology 2016-01, Vol.158, p.275-285
• Main Authors: Asadollahzadeh, Mehdi, Torab-Mostaedi, Meisam, Shahhosseini, Shahrokh, Ghaemi, Ahad, Torkaman, Rezvan
• Format: Article
• Language: English
• Subjects: Acetone; Correlation; Dispersed phase holdup; Dispersion; Kühni column extractor; Liquid–liquid extraction; Mass transfer; Mathematical analysis; ORC column extractor; Phase velocity; Purification; Rotor speed
• ISSN: 1383-5866; 1873-3794
• DOI: 10.1016/j.seppur.2015.12.030

[Display omitted] •Dispersed phase holdup data have been obtained for Kühni and ORC columns.•Effect of solute transfer in two directions between two phases was investigated.•The proposed equation paves the way for accurate predictions for the holdup.•The correlation can be incorporated in the design for Kühni and ORC columns. Dispersed phase holdup data have been obtained for Kühni and ORC columns with investigation on three different systems (toluene–water, n-butyl acetate–water, n-butanol–water). The effects of operational variables such as mass transfer directions with acetone transfer, rotor speed and dispersed and continuous phase velocities have been investigated. The dispersed phase holdup was influenced mainly by mass transfer direction, agitation speed and velocity of the dispersed phase. Calculations with the literature equations cannot predict experimental data, thus a unified correlation considering the geometric parameter was provided to predict holdup. The correlation involving Froude number, phase velocities, modified property group along with those of geometry factor fits the experimental data well. The results of the proposed correlation were compared with the experimental data obtained from the literature and the present investigation. Findings of this study demonstrated that the proposed correlation leads to an accurate prediction for the dispersed phase holdup.