GB1042081A - Improvements relating to the freeze drying of materials - Google Patents

Abstract

1,042,081. Freeze-drying. LEYBOLDHOCHVAKUUM ANLAGEN G.m.b.H. Jan. 22,1964 [March 2, 1963], No. 2745/64. Heading F4G. [Also in Divisions A2 and G6] A method of freeze drying materials wherein the material is fed from a hermetically sealed storage container into a freeze drying chamber, dried therein and discharged to a hermetically sealed collecting chamber, the feeding, drying and discharging operations being controlled without the material being exposed at any time to atmosphere. In freeze drying apparatus, the material is fed from a hermetically sealed storage container (not shown), via a valved pipe and feed means 51 into a chamber 2 on to one or more horizontal discs 29 mounted on a rotatable vertical shaft 26 through which a coolant may pass to pipes 21 within the discs 29, and the chamber is ventable through a valve 233. Heat medium for sublimation is passed through the shaft 26 and pipes 21 and the chamber is put into communication with a condensing chamber 3 connected to a pump 4 by opening a gate 33. The material is spread on the discs 29 by elements 25 which can be raised or lowered and perform a figure-of-eight-movement through actuating means 251, which spreaders also dislodge the material when dry to fall through a valved floor portion 27 into a hermetically sealed collecting vessel 28.