VEVOR HFD-4 Bedienungsanleitung Seite 7

relative humidity： ≤70%
supply voltage：single phase220V-230v or120v
Horizontally, no conductive dust, explosive, corrosive gas and
electromagnetic interference.
2.Delivery and storage condition: ambient temperature :-35℃～50
relative humidity： ≤93%
Storage environment should be well ventilated, non corrosive gas.
3.Security class I type B
Normal information for vacuum freeze drying
1.Basic knowledge
Vacuum freeze-drying is one of the most gentle ways to dry. It is based on
the sublimation principle, that is, the solid phase directly into the gas phase
of this physical phenomenon. The freeze-dried material is placed in a
vacuum drying chamber for drying, and the water vapor produced by the
cold trap is condensed to form ice, so as to achieve the purpose of
eliminating water vapor. Vacuum pump is used to discharge the air in the
drying room, not including water vapor.
The baffle plate is provided with a heating device, and the heat is
transferred to the material through the conduction function to provide the
energy needed for sublimation. When the free water in the material is
sublimated, the internal bound water can also be removed from the
material at a very low vacuum. This drying process is considered to be the
last stage of drying, analytical drying.
Sublimation
The principle of sublimation can be explained briefly with water map. When
the pressure is higher than 611Pa, the water will go through three phases
of solid, liquid and gas. When the air pressure is equal to 611Pa, the
dissolution curve, the vapor pressure curve and the sublimation curve
three lines are at one point, that is, the three phase point. When the
pressure is lower than 611Pa and reached the sublimation curve, the ice
can be directly into a solid state gas.
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