Continuous Measurement of Crystal Number Concentration in Crystallization of Fructose by Laser Diffraction Method

Abstract

The continuous measurement of the number concentration of growing crystals in the crystallization of fructose was attempted by using a commercial laser diffraction particle size analyzer. It is based on the relation that the maximum diffracted light intensity at the detector is proportional to the crystal number concentration and the square of mean crystal size, which is formulated for the non-growing particles.
The crystal number concentration measured by the laser diffraction particle size analyzer almost agrees with that by microscopic observation unless generation of small crystals such as secondary nuclei occurs. The generating point of small crystals is detected approximately by monitoring the ratio of mean diffracted light intensity at the whole detector to the maximum one.