Wet granulation is fundamentally a batch process, which can be divided into two types: high shear and fluid bed granulation. In the course of wet granulation small and/or irregular shaped particles (e.g. needle crystals) are cohered together with the help of a granulation liquid (usually water or a certain alcohol) and a binder material (e.g. polyvinylpyrrolidone) to form larger and more spherical particles. The main purpose of the granulation is to improve the flowability and increase the bulk density of the powder to facilitate the tableting process.
The batch type wet granulations are foreseen to be replaced by continuous wet granulation in the pharmaceutical industry in the near future. The shift from batch to continuous technologies has been recommended by Food and Drug Administration. This continuous wet granulation technology can be carried out on a twin-screw extruder into which solid materials and water can be fed at various parts. In the extruder the materials are mixed and granulated due to the intermesh of the screws, especially at the kneading elements. We are ready and eager to investigate continuous wet granulation of your material on our lab-scale, GMP compatible extruder.