Dry granulation as a twin-screw process in pharmaceutical applications

Introduction Two different processes can be performed using parallel co-rotating twin-screws (see Fig. 1): If a die is placed at the end of an extruder barrel, and material is compacted and pressed pressed through this die, then the process is called extrusion. By omitting the die the material can be kneaded and agglomerated in the barrel without an increase in pressure. This process is called granulation. Both processes can be performed with and without water.