Determinants of the Duration of the Main Drying Process of a Four Ring Freeze Dryer

With the development of vacuum freeze-drying technology, Sihuan freeze-drying freeze-drying machine plays an important role in universities, laboratories and scientific research fields
.

It is also widely used in experimental scientific research fields such as life sciences, biopharmaceuticals, chemical materials, food and nutrition
.

Advantages of Sihuan Freeze Dryer: 1.
Many hot substances will not be denatured or inactivated
.

2.
When drying at low temperature, the loss of some volatile components in the material is very small
.

3.
During the freeze-drying process, the growth of microorganisms and the action of enzymes cannot be carried out, so the original characters can be maintained
.

4.
Due to the drying in the frozen state, the volume is almost unchanged, the original structure is maintained, and the phenomenon of concentration will not occur
.

5.
Since the water in the material exists in the form of ice crystals after pre-freezing, the dissolved inorganic salts originally dissolved in water are evenly distributed in the material
.

During sublimation, the dissolved substances dissolved in water are precipitated, which avoids the phenomenon of surface hardening caused by the precipitation of inorganic salts carried by the migration of moisture inside the material to the surface in the general drying method
.

6.
The dried material is loose and porous, and it is sponge-like.
After adding water, it dissolves quickly and completely, and it restores its original properties almost immediately
.

7.
Since the drying is carried out under vacuum, there is very little oxygen, so some easily oxidized substances are protected
.

8.
Drying can remove more than 95% to 99% of the moisture, so that the dried product can be stored for a long time without deterioration
.

9.
Because the material is in a frozen state and the temperature is very low, the temperature of the heat source for heating is not high, and a heater with normal temperature or low temperature can meet the requirements
.

If the freezing type and the drying type are separated, the drying type does not need heat insulation, and there will not be a lot of heat loss, so the utilization of heat energy is very economical
.

The determinants of the duration of the main drying process of the four-ring freeze-drying freeze dryer mainly depend on: 1.
The thickness of the material 2.
The heat delivered to the material during the drying process 3.
The pressure increase in the drying type during the drying process The pressure can be increased Sublimation rate
.

Shorten the dryer period
.

The water vapour produced during the main drying stage is not pumped away by the vacuum pump, but is captured by the condenser
.

The role of the vacuum pump is to reduce the partial pressure of the non-condensable gas so that water vapor can be transferred from the substance to the condenser
.

However, a small amount of water vapor is still evacuated by the vacuum pump, so a gas ballast device must be installed on the vacuum pump
.

If the gas ballast valve is opened, the extracted condensable steam is mixed with air through the exhaust pipe and discharged
.

In general, closing the gas ballast valve for operation is not necessary
.

By opening the gas ballast valve, the final pressure that the vacuum pump can reach is equivalent to that of the partial pressure of water vapor
.