A DEM-based mechanistic model for scale-up of industrial tablet coating processes
In this study, a mechanistic model was developed for industrial scale-up of tablet coating processes. The model considers tablet coating based on first principles and aims to keep the coating process as closely equivalent as possible on scale-up. As part of the model, DEM was employed to find tablet velocities and residence times at the tablet bed surface and in the spray zone.
Both constant Froude number and constant circumferential speed, were evaluated to scale pan speed. Several methods for scaling spray rate were integrated into the present model. Following the model, consistent film thickness per pass can be retained on scale-up at constant circumferential speed.
Comparison of spray rate prediction and experimental data shows adequate performance of the model. The model can be further used to estimate spray flux, film thickness per pass and number of coating passes. The results can be useful to select process parameters on scale-up.
Keywords: DEM, Mechanistic model, Scale-up, Tablet, Coating