Acoustic Emission: a new in-line and non-intrusive sensor for monitoring batch solution crystallization operations

Acoustic emission (AE) is shown to provide complex and in-depth information on both the liquid and the dispersed phases during batch cooling solution crystallization processes. Despite its complexity, such information might be highly valuable for process monitoring and control purposes owing to its non-intrusive features, its relative cheapness, and the very wide scope of its potential applications. Basic crystallization phenomena such as the onset of nucleation and the development of crystal growth, several key-process variables like the concentration of solid in suspension, and overall data describing the average particle size and the content in impurities of the crystallization medium are evaluated from real experimental data obtained at the lab-scale. AE is not claimed here to allow replacing “usual” particle sizes sensing technologies like image analysis or FBRM; it is rather suggested that the large amount of information contained in the acoustic data is quite interesting and deserves further investigation.