Numerical analysis of crystallization of high aspect ratio crystals with breakage

• Bivariate population balance model is developed for high aspect ratio crystals.
• The set of equations for mixed moments is solved by 2D quadrature method of moments.
• Nucleation, size-dependent growth and breakage along the length are analysed.
• The properties of crystals product are compared for four binary breakage functions.
• The analysis reveals nonlinear interactions and inverse effects of sub-processes.

Two-dimensional population balance model for continuous cooling crystallization of high aspect ratio crystals, including nucleation, size-dependent growth of the two characteristic crystal facets and binary breakage along the crystal length is developed and analysed. The population balance equation is solved numerically using the 2D quadrature method of moments. The behaviour of the crystallizer and the effects of kinetic and process parameters on the characteristics of the crystal size distribution are analysed by detailed numerical experimentation. The binary breakage is described by four breakage rate functions comparing their effects on the mean length and mean aspect ratio of crystals. The simulation results revealed several interesting phenomena caused by interactions of the nonlinear sub-processes playing a relevant role in formulation of high aspect ratio crystals. Interactions of nucleation and size-dependent breakage may induce decrease in production of crystals. Size-dependent crystal breakage, decreasing the mean length of crystals induces some increase in their mean width.

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