Comparison of the effects of different drying techniques on properties of granules and tablets made on a production scale.

The aims of this study were to compare the properties of granules prepared in a high-shear granulator and dried by using different methods (fluid-bed and microwave-vacuum drying) and to compare the properties of tablets pressed from such granules. Experiments on a production scale were performed with Collette Ultima Pro 600 single-pot processing equipment and a Glatt WSG 200 fluid-bed granulator and drier. The particles granulated in the traditional high-shear granulator and dried in a vacuum chamber had a higher porosity and higher bulk and tapped densities, as a consequence of the special characteristics of the drying process. They retained their spherical form, in contrast with the particles dried via the fluid-bed technology. The two types of granules required different compressing forces for tabletting.