(310c) Population Balance Modeling of Aspect Ratios in Crystal Breakage

The aspect ratio is a commonly used shape factor that is used to characterize particles.  Previous research has shown that when particles are broken, the child particles can have different shape factors – in some cases the smaller particles have higher aspect ratios.  This has been shown experimentally with NaCl crystals that are cubic. 

One challenge is to model this using Population Balance Equations (PBEs).  The goal is to develop realistic functions for modeling the changes in the aspect ratios.  In previous efforts a single function was developed based on the ratio of the child volume to the parent particle volume.  While this function worked well for some cases, it did not match experimental results for other cases.  This work presents recent developments in modeling fragmentation of cubic crystals that accounts for both changes in particle size and aspect ratio.  New models are presented that account for a wider range of observed breakage results.