(340f) Evaporative Heat Transfer Model for QbD of Agitated Filter Bed Drying

Drying of an active pharmaceutical ingredient (API) is an important unit operation in the pharmaceutical industry as it is used to control residual solvent content, in addition to controlling appropriate physical properties. Drying operation is often time consuming and may turn out to be a bottleneck in the overall process cycle time. Many APIs are potent compounds that require filtration and drying to be done in a single contained vessel, known as an agitated filter dryer (AFD), to minimize operator exposure.

Scale-up/tech-transfer of drying process is quite challenging as different AFDs have different surfaces that could transfer heat that ends up impacting effective heat transfer coefficients across the bed as we scale the process. Understanding of bed temperature and residual solvent across the filter cake is critical for reliable and robust scale-up of AFD drying protocol.

In this work, we present results from a novel 3D heat-transfer model that allows us to understand the temperature evolution across the filter cake considering the equipment variability at scale. We also present experimental techniques that can be employed to extract relevant model parameters. In the end, we would provide the decision tree to guide efficient design and reliable scale-up of agitated filter drying.

Disclosures:

All authors are AbbVie employees and may own AbbVie stock. AbbVie sponsored and funded the study; contributed to the design; participated in the collection, analysis, and interpretation of data, and in writing, reviewing, and approval of the final abstract.