Kleinebudde P, Sølvberg A J, Lindner H
Department of Pharmaceutics and Biopharmaceutics, Christian-Albrechts-University, Kiel, Germany.
J Pharm Pharmacol. 1994 Jul;46(7):542-6. doi: 10.1111/j.2042-7158.1994.tb03853.x.
Based on the assumption that there is a link between power consumption of an extruder and pellet properties, a control circuit for power consumption was developed. Powder and granulation liquid are fed separately into a twin-screw extruder. The power consumption is controlled by varying the pump rate at a given powder-feed rate; consequently each level of power consumption results in a specific water content of the extrudate for a particular formulation. The shape of pellets depends almost entirely on the level of power consumption irrespective of formulation. The size of dry pellets is additionally affected by a shrinking factor which depends on the water content. The power-consumption-controlled extruder is an appropriate tool for the production of pellets. The system is able to adapt the water content for a formulation automatically.
