ABSTRACT
The freeze dryer (Plate 2.1) is the machine that converts the theory of freeze drying into the reality of the production of a freeze-dried prod uct. The freeze dryer is an unusual item of equipment; it is not gener ally understood, and it is usually the bottleneck in production flow. Whilst there is little of a highly technical nature within the machine, it incorporates many technologies, thus making maintenance, repair, and spares holding as well as procurement, unusually difficult. Nev ertheless, most pharmaceutical companies utilise freeze drying as a production technique for at least one of their products.
