Tag Archives: control

Crystallization control: measuring supersaturation with ReactIR, or measuring crystal nucleation and growth with FBRM

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Crystallization control

A question was posted regarding crystallization monitoring and control:

“If you had to choose between supersaturation control or FBRM crystal size control on an industrial scale, which would you choose?”

Supersaturation monitoring and control only makes sense if you have a very reliable model of the system (i.e. where you can predict nucleation and growth as a function of supersaturation), stable reactor control, and a precise supersaturation measurement.

In R&D this is certainly achievable, and there are good examples of supersaturation control including this on-demand webinar, by Dr. Mark Barrett, describing calibration-free supersaturation control.

However, in an industrial crystallizer, your supersaturation-based control would likely be based on limiting the level of supersaturation to avoid conditions that would produce high levels of spontaneous or secondary nucleation.

And that’s not really control, just avoidance.

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