Freeze-drying equipment for large-scale laboratory use

Abstract

Equip-ment is described for the routine freeze-drying of material on a large laboratory scale with the minimum of handling and attention. The evaporative spin-freeze principle is used throughout. Details are given of various special features of design, and of the methods used for the measurement of the temperature of drying material in rotating containers, and of the vacuum in low-pressure air-water-vapor systems. Practical advantages and disadvantages of this type of equipment are discussed and the performance is illustrated by a typical freeze-drying cycle.