Powdering While Drying
All parts in contact with the product are made of AISI 316L (1.4404) stainless steel as standard, with other weldable materials such as Hastelloy C-22 (2.4602) and AISI 904L (1.4539) on request. The gentle curves of the drying chamber, with no sharp edges or corners, allow surfaces to be coated with fluoropolymers if required, for maximum resistance to corrosion. Italvacuum has also produced enameled versions in which the steel is protected by a layer of alkaline borosilicate.
The same smooth internal surfaces, combined with the rotation of the drying chamber and the action of the lump–breaker, makes the Criox system easy to clean. Only a few rinses with small quantities of fluid are needed to meet FDA standards for cleanliness, and only a small amount of wastewater needs to be disposed of. The internal CIP spray make product changeover even quicker.
The filter on any vacuum dryer must be able to keep all the powder in the chamber, letting only the solvent vapors pass through, yet with the lowest possible pressure drop, so as to allow the maximum final vacuum. Italvacuum offers several filter systems to meet these requirements, with sintered metal cartridge filters or PTFE filters mounted inside the drying chamber. A nitrogen backflush system stops the filter from blinding.
The lump–breaker blades can easily be disassembled thanks to their small size, and the filter system can be removed from the outside. Internal inspection and swab testing is easily done via an access port or the loading hopper. External cleaning is also easy and effective. Sealed external cladding is available to cover all insulation and electrical, hydraulic and pneumatic lines. This feature also allows partitioning solution for the complete separation of clean room from machine room. Partitioning permits to isolate the drying chamber, leaving all the auxiliary groups in the technical room: in this way powders handling for loading and unloading the product is confined in the clean room, thus eliminating any risk of contamination.