Scale-Up Study on the Performance of the Asymmetric Rotating Impeller Extraction Column

Abstract

In the present work, hydrodynamics and mass transfer performance of the asymmetric rotating impeller column (ARIC) of different scales, that is, ARIC 1 (I.D. = 0.1 m), ARIC 2 (I.D. = 0.22 m), and ARIC 3 (I.D. = 0.3 m), have been investigated. The liquid−liquid system used in the present study is phosphoric acid containing metal ions and the organo-phosphorous solvent. The effect of different operating conditions on regime transition in ARIC of different scales has been analyzed. Correlations have been developed for the prediction of holdup and drop size in the ARIC of different scales. The average absolute relative error values in the prediction of holdup and drop size using these correlations are 10 and 9%, respectively. An increase in the height of transfer unit is observed with an increase in throughput and column diameter. The results indicate that adequate design and scale-up of extraction columns can be carried out based on geometric similarity.

CFD Modeling of Liquid–Liquid Batch-Stirred Tank at High Organic to Aqueous Phase Ratios

“…q p e 2.5 (13) Various drag models are investigated in the present study, and a comparison between experimental and simulated results has been made. In liquid−liquid dispersions, multiple factors affect the drag coefficient.…”

“…However, the current universal drag models do not account for these parameters. 13 The dependency of the drag coefficient on the volume fraction was analyzed for the various models. In the present study, simulations were conducted to examine the influence of various drag models, such as Universal, Schiller−Naumann, Ishii−Zuber, and Kumar−Hartland, on the holdup distribution in a stirred tank.…”

“…The deformations of the droplets can also impact the internal circulations, leading to increased drag on the dispersed phase particles. However, the current universal drag models do not account for these parameters . The dependency of the drag coefficient on the volume fraction was analyzed for the various models.…”

“…Different extraction equipment are available, such as a mixer-settler, rotating disc column, sieve-plate column, asymmetric rotating disc/impeller column, pulse disc, and doughnut column . A past study found that an asymmetric rotating impeller column (ARIC) gives the best results for the recovery of metal ions from wet phosphoric acid. − Hendre et al have experimentally observed that 99% of metal ions can be extracted from the loaded phosphoric acid in ARIC . Considering the amount of solvent required for extraction, the cost of organic solvent, and the recovery of solutes, stripping of the “loaded” organic phase is an essential step in the extraction process.…”

Modeling the axial distribution of mass transfer coefficient in an agitated‐pulsed extraction column

“…[20][21][22] In ADM, the product of mass transfer coefficient and interfacial area is simplified as a constant through the height of the column. 23 However, experimental results have demonstrated that the dispersed phase holdup and drop size in contactors vary significantly along the column height, 3,[24][25][26] which not only leads to a longitudinal variation of specific interfacial area but also affects axial distribution of the mass transfer coefficient. 27 Consequently, more reliable theoretical methods for predicting mass transfer behavior are needed in the designing and scaling-up of such extractors.…”