Scale-Up and Interpretation

Scale-up techniques for using the results of pilot plant or bench scale test work 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 with product concentrations, gas dispersions, heat transfer, solids suspensions, or others. 

These scale-up methods will necessarily at times include fundamental concepts, dimensional analysis, empirical correlations, test data, and experience [32]. 

Similarity concepts use physical and mathematical relations between variables to compare the expected performance of mixing/agitation in different sized systems [33]. This is usually only a part answer to the scale-up problem. 

Geometric similarity is often considered the most important feature to establishing similarity in mixing, basing the scaled-up larger unit on the smaller initial model or test unit. 

The scale-up of mixing data has been treated with a variety of approaches, some to rather disastrous results. The principles are now well established, and it is a matter of truly understanding the par ticular systems that poses 

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