An Alternative Viewpoint For Scale-up

Reproduced from Chem. Eng. Progr. Vol. 70, No. 5, p. 79 with permi.ssion of the American Jn.stitute of Chemical Engineers, 1974 AICHE. All rights reserved. 

To achieve the goal set above, measurements for reaction rates must be made in a RR at the flow conditions, i.e., Reynolds number of the large unit and at several well-defined partial pressures and temperatures around the expected operation. Measurements at even higher flow rates than customary in a commercial reactor are also possible and should be made to check for flow effect. Each measurement is to be made at point 

Both the pilot-plant and commercial reactors are the same length (60 feet), and all three use the same mass velocity and can be operated at various conditions. 

Their location represents the range of the conditions that should be used in a statistically designed set of experiments for kinetic studies and not actual conditions at the particular location. This way, the same flow is again maintained on all three scales and the troublesome effect of changing flow conditions on scale-up can be eliminated. The proposed idea, for scale-up by scale-down from the view point of the catalyst, was proven to be effective in many industrial projects. 

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