Mathematical modeling of an aqueous film coating process in a Bohle Lab-Coater, Part 1: Development of the model
The purpose of this study was to develop a model to predict (1) air; product temperatures, (2) product moisture,; (3) air humidity during an aqueous coating process using a Bohle Lab-Coater. Because of the geometrical properties; the airflow, the drum of the Bohle Lab-Coater can in principle be divided into 2 zones of equal size—the drying; the spraying zones. For each zone, 4 balance equations could be set up describing the change of the air humidity, the product moisture, the enthalpy of the air,; the enthalpy of the product in each zone. For this purpose, knowledge regarding heat; mass transfer; also the motion of the tablets in drums was used. Based on the considerations of the heat; mass transfer, a set of first-order coupled ordinary differential equations (ODEs) was developed. This set of ODEs can be solved numerically. In this part, the development of the model is described in detail, whereas the application of the model can be found in part 2.
Susanne Page1?Karl-Heinrich Baumann2?Peter Kleinebudde3Email:Kleinebudde@uni-duesseldorf.de
[1] Institute of Pharmaceutics; Biopharmaceutics, Martin-Luther-University Halle-Wittenberg, Wolfgang-Langenbeck-Str 4, D-06120 Halle, Germany ;[2] Department of Engineering, Martin-Luther-University Halle-Wittenberg, Geusaer Str 132, D-06217 Merseburg, Germany ;[3] Institute of Pharmaceutics; Biopharmaceutics, Heinrich-Heine-University Duesseldorf, Universitaetsstr 1, 40627 Düsseldorf, Germany ;[4] Present address: F. Hoffmann-La Roche Ltd, Basel, Switzerland
