Wiped wall rotating molecular vacuum still - having several pressure zones separated by rotating vacuum seals

摘要

Multi-stage vacuum and molecular distn. still has wiped walls with a single cylindrical or conical body or a combination of the two. The heat transfer surface is wiped by a single drive mechanism, this being sealed in which a vacuum tight seal capable of holding the lowest pressure encountered. Between the different vacuum stages are rotating vacuum seals to transmit the wiping action from one stage to the next. The number of stages is optional. The wiper in one section is connected to that in the next by a system of segments mounted in Teflon (RTM) tubes of an endless spiral. The same sort of connections can be made across all the rotating seals. The inner evaporator body is divided into individually controlled heating cells corresp. to the pressure distribution in the outer process space. For use on distn. and sepn. of materials under vacuum and with an agitated heat transfer surface. The system gives multi-stage operation in a single unit which maintains the advantages but avoids most of the disadvantages e.g. blockage from degradation prods.