Development of an empirical method relating crystal size distributions and FBRM measurements

The empirical model developed in the present work allows estimation of crystal size distributions from focused beam reflectance measurements (FBRM) of chord length distributions. The model is constructed from purposely varied crystal size distributions and the corresponding measured chord length distributions, which allows construction of a transformation matrix relating the two distributions. Experimental results show advantages over more complex phenomenological models, presumably because the transformation matrix implicitly embodies such phenomena. The ability of the model to address varying crystal concentration and selectively added size fractions is demonstrated with experimental results. Finally, the simplicity of the approach allows rapid (of order 0.1 s) estimation of crystal size distributions from FBRM, which is a promising outcome for potentially using the approach in an on-line control scheme.

► A model relates focused beam reflectance measurements to crystal size distribution. ► The model is constructed empirically using known crystal size distributions. ► Experimental results demonstrate the practicality of the method. ► Two inversion methods estimating crystal size distribution are studied and applied.