The manufacturing of active pharmaceutical ingredients and intermediates require reliable and gentle treatment during solid-liquid separation with succeeding drying of the wet cake. Highly efficient contact vacuum dryers ensure effective drying performance and high operational reliability with low product degradation due to thermal and mechanical influences.
Gentle drying of active pharmaceutical ingredients is of particular importance. Because fast rotating agitators or agitators causing high shear forces lead to unwanted particle distribution as well as product compression with the result of granulation in the worst case. These granules require the use of mills, sieves or even choppers which additionally are further mechanical impact to the usually crystalline active ingredient. This should be avoided.
To prevent possible changes or damage of the crystal structure of the product or damage due to overheating (burning or melting), high shear forces, local compaction or agitator-related overheating of the product should be avoided. Therefore, slow rotating, shear force reducing agitators are the first choice for homogeneous batches. Both horizontal and vertical dryers are used in the industry.
Horizontal dryers can process large volume batches and require smaller room heights. Vertical dryers can be very well integrated into processes using gravitation in manufacturing stream. In example, on the top floor are the reactors, followed by agitated nutsche filter or centrifuges floor, followed by the dryer floor, followed by further dry product handling.
