Centrifugal contactors scale

Meikrantz, D.H., Law, J., Todd, T. 2007. Design attributes and scale up testing of annular centrifugal contactors. Chemical Engineering Division of the AIChE Spring National Meeting, April 10-14, 2005, Atlanta, GA. INL/CON-05-00088. 

The flowsheet described in Figure 3.20 was then implemented twice in small-scale centrifugal contactors in June 2001 in the ATALANTE hot cells (3) ... 

Law, J., D. Meikrantz, T. Gam, et al. 2006. The Testing of Commercially Available Engineering- and Plant-Scale Annular Centrifugal Contactors for the Processing of Spent Nuclear Fuel. 15th Pacific Basin Nuclear Conference, October 15-20, Sydney, Australia, Idaho National Laboratory Report INL/CON-06011498 PREPRINT, Idaho... 

Leonard, R. A., D. B. Chamberlain, and C. Conner. 1997. Centrifugal Contactors for Laboratory-scale Solvent Extraction tests. Sep. Sci. Technol. 32(1-4), 193-210. 

Leonard, R. A., C. Conner, M. W. Liberatore, et al. 1999. Evaluation of an Alkaline-Side Solvent Extraction Process for Cesium Removal from SRS Tank Waste Using Laboratory-Scale Centrifugal Contactors. Argonne National Laboratory Report ANL-99/14, Argonne, IL. 

Typical extraction curves obtained in our laboratory scale apparatus show that Murphree s efficiency ( E ) varies with the nature of the solvent and with mixing time figure 7 . From the linear dependence of E/l-E on mixing time, it may be concluded that our centrifugal contactor can be assimilated to a perfectly stirred continuous reactor of which the characteristic equation is (19)... 

Centrifugal contactor Works at low density differences between two fluids Less solvent volume required for extraction Rapid mixing and separation can enhance product recovery and cost Difficult to scale up Mechanical complexity and high maintenance cost... 

While solvent extraction is often done on a small scale by synthetic lab chemists using a separatory funnel or Craig apparatus, it is normally done on the industrial scale using machines that bring the two liquid phases into contact with each other. Such machines include centrifugal contactors, thin layer extractors, spray columns, pulsed columns, and mixer-settlers. 

One attempt to improve the situation has been successful for small to moderate scale operations where high purity is required—namely, the Podbielniak centrifugal counter-current contactor and separator, which dominates the solvent extraction phase of penicillin manufacture. 

Laboratory Extractors. Pilot-Scale Testing, and Scale-Up. Several laboratory units arc useful in analysis, process control, and process studies. The AKUFVE contactor incorporates a separate mixer and centrifugal separator. It is an efficient instrument for rapid and accurate measurement of partition coefficients, as well as for obtaining reaction kinetic data. Miniature mixer-settler assemblies set up as continuous, bench-scale, multistage, countercurrent, liquid-liquid contactors are particularly useful Tor the preliminary laboratory work associated with flow-sheet development and optimization because these give a known number of theoretical stages. 

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