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Because most processes are scale dependent, scaling up from laboratory experiments
to full-scale commercial production can be
a nightmarish experience. Often, commercial plants are built based on data generated
in the laboratory only to find that the kinetics of the larger-scale process is different,
the product purity is way off, and reaction
times are unacceptable.
This is just the best-case scenario. In the worst case, uncon-
trolled heat build-up in your plant can lead to runaway reactions
and explosions. How? Exothermic reactions conducted in
lab glassware may not accurately measure thermal build-up,
because heat from the small reaction dissipates out of the glass-
ware quickly and temperature is maintained easily. But, when
the process is scaled up, the heat transfer is slower and, if the
plant design does not accommodate it, the heat build-up could
lead to a runaway reaction (Fig. 1).
pilot plants: smoothing the
scale-up from lab to commercial
FIG. 1. The Surface area-to-volume ratio decreases as the size
of the vessel increases, thereby reducing the heat transfer area.