A simple method for evaluating the mixing efficiency of a new type of pan coater.

The objective of this study was to investigate some important process parameters on the mixing behavior of a new coater type. The coater used in this study, the Bohle BLC pan coater, differs from other coaters in its high length to diameter ratio. The pan coater can be divided into two zones: drying and spraying zone. The temperature difference between two points in the pan (one in each zone) was used to explore the influence of some process parameters, i.e. the pan speed and the inclination of the rotation axis on the mixing behavior. In addition, the effect of the spray rate on the temperature difference was studied. The results of the current study demonstrated the possibility to characterize the mixing behavior in a pan coater by a simple temperature measurement. The temperature difference method resulted in a model, which was comparable to the model from a conventional mixture experiment. It was shown that the pan speed and the spray rate influenced the temperature difference and, consequently, the mixing efficiency. However, the inclination of the rotation axis did not show an important effect.