Reducing Time of Crystals Formation in Crystallizer using a Hydrofoil as an Impeller and Air Bubbling through the Mixture

Abstract

Crystallization is one of the most important unit operation in Pharmaceutical industries. Many industries use this equipment in order to obtain the product in crystals for and supply it to the tablet manufacturing companies. We received a problem statement from Granules India Ltd. stating that the cycle time required for crystallization of paracetamol is taking nearly 6hrs for completion. Our task was to reduce the cycle time of the crystallization process. It consisted of 3 stages, mixing time, cooling time and crystals formation time. The temperatures went on decreasing after each stage. We suggested the use of a hydrofoil instead of an anchor and passing air bubbles. Based on the literature survey we concluded that use of hydrofoil reduces cycle time and faster crystallization with the help of air bubbling. Our focus is to study the implementation of hydrofoil and air bubbling in various other crystallizers such batch cooling crystallization, anti-solvent crystallization etc.