Vacuum freeze drying is a good way to current material dehydration, it can be freeze-dried material, frozen in advance, and then under the condition of low temperature low pressure, material moisture, sublimation, achieve the purpose of dehydration. The sublimated water vapor is collected by condensation. After this vacuum freeze dry operation of the material, it becomes dehydrated.
After vacuum freeze – drying, the enzymatic action is weak, the original chemical and physiological properties are basically unchanged, and the dry materials are porous, and the volume is basically unchanged, which is easy to recover. In particular, the vacuum freeze-dried substances can be preserved for years without deterioration.
Condenser is used for condensation of water vapor distillation equipment, its work excessive degree can reach to 45 ℃ ~ 60 ℃, cold source is made up of two 2 f6. Type 3 freon refrigerating unit.
The vacuum unit of the dryer is composed of two rotary vane mechanical vacuum pumps and one roots mechanical booster pump. The vacuum unit is connected with the desiccant box and condenser through the vacuum pipe and vacuum valve to form a sealed vacuum system. The vacuum unit is equipped with a contact vacuum meter, which can automatically control the start of roots pump according to the pre-selected vacuum level. There is a vacuum butterfly valve in the vacuum tube between the desiccant box and the condenser.
The bottom of the condenser is equipped with the branch tube road and heat fan. In the partition with 50 butterfly valve, the valve and the branch pipe is used for condenser frost dry, roots pump vacuum tubes, is used alone the path when mechanical vacuum pump, it is equipped with solenoid valve, when the roots pump starts, the rich will be automatically closed. Vacuum tubes, equipped with electrical tape deflated cut-off valve, when the vacuum pump stops automatically close the vacuum line, the air into the pump at the same time, to avoid vacuum pump oil into the vacuum line by negative pressure effect. The connecting pipe of the vacuum pump is provided with corrugated hose to prevent vibration from transmitted to its components during operation.