Testing and scale

As with the design of the other columns described above, the design of a Scheibel column must be based on pilot plant tests and scale-up, The following procedure is recommended ... 

Since testing and scale-up are different for batch and continuous filtration, discussion in this section will be limited to continuous filtration. 

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. 

Since operation of TRU began, numerous process changes have been made to counteract problems caused by equipment corrosion, to satisfy new processing requirements, and to utilize improved processes. In initial operations at TRU, unexpected corrosion of the Zircaloy-2 equipment occurred in high specific-activity chloride solutions, and the dissolved zirconium caused operating problems that made some of the flowsheets for the processing steps either difficult to operate or totally unusable. Because of these and other problems, several new flowsheets were devised or adopted, tested, and scaled to pi ant-size equipment. 

Pratt, H. R. C., and Stevens, G. W. (1992). Selection, design, pilot-testing, and scale-up of extraction equipment. In Science and Practice of Liquid-Liquid Extraction (J. D. Thornton, ed.), Vol. 1, pp. 492-589. Oxford University Press, New York. 

Vacuum and pressure laboratory filtration assemblies are shown in Figure 11.7. Mild agitation with air sometimes may be preferable to the mechanical stirrer shown, but it is important that any agglomerates of particles be kept merely in suspension and not broken up. The test record sheet of Figure 11.8 shows the kind of data that normally are of interest. Besides measurements of filtrate and cake amounts as functions of time and pressure, it is desirable to test washing rates and efficiencies and rates of moisture removal with air blowing. Typical data of these kinds are shown in Figure 11.3. Detailed laboratory procedures are explained by Bosley (1977) and Dahlstrom and Silverblatt (1977). Test and scale-up procedures for all kinds of SLS equipment are treated in the book edited by Purchas (1977). 

Laboratory Testing and Scale-Up 317 Compression-Permeability Cell 317 The SCFT Concept 317... 

It is not within the scope of this report to give a full account of the basic tests and scale-up theory but there are some fundamental concepts in particle characterization that have to be stated here. 

H. P. C. Prati and C. Hanson, Selection, Pilot Testing, and Scale-Up of Commercial Extractors,... 

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