| 摘要 |
The invention relates to a freeze-drying facility comprising the receiver (1) for the material to be freeze-dried, a molecular pump (3), the condenser (4) for removing the water vapour, and a rotary vane pump (5), all connected in series. Thus the condenser receives already compressed condensate, and can be operated at temperatures that are not so low as for a condenser connected directly to the receiver. This arrangement prevents in particular back-diffusion of hydrocarbons from the rotary vane pump (5) into the receiver (1), which is especially important for freeze-drying of foods. <IMAGE>
|
