Mixer heat-transfer method

Scale-up techniques for using the results of pilot plant or bench scale test w ork to establish the equivalent process results for a commercial or large scale plant mixing system design require careful specialized considerations and usually are best handled by the mixer manufacturer s specialist. The methods to accomplish scale-up will vary considerably, depending on whether the actual operation is one of blending, chemical reaction tvith product concentrations, gas dispersions, heat transfer, solids suspensions, or others. 

The second method uses dimensionless numbers to predict scale-up parameters. The use of dimensionless numbers simplifies design calculations by reducing the number of variables to consider. The dimensionless number approach has been used with good success in heat transfer calculations and to some extent in gas dispersion (mass transfer) for mixer scale-up. Usually, the primary independent variable in a dimensionless number correlation is Reynolds number ... 

Heat and mass transfer has already been included in the discussion of kinetics, but it is worth mentioning some of the areas where intensified heat and mass transfer are attractive, but no reactions are taking place. Several of the applications of PI discussed in Chapters 9 and 10 are of this type and highly compact heat exchangers, electrical enhancement methods, such as ultrasound, and induction-heated mixers are examples of where a need to improve heat and/or mass transfer has been recognised. In some of these examples the heat transfer may be limiting because of the nature of the material being heated or cooled. As discussed in Chapter 9, the... 

This chapter presented methods for scaling heat transfer equipment using dimensional analysis. We scaled heated, uninsulated storage tanks heated, insulated batch mixers and heat exchangers in this chapter. 

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