There are many factors that affect the drying process of a freeze dryer and its freeze-drying quality, such as material properties, concentration, sublimation area, eutectic point, heat transfer medium and method, equipment performance and other factors. The lyophilization technician should mainly pay attention to the following factors.
1. The thickness of the material directly affects the drying time of the material, because the greater the thickness of the material, the greater the resistance to heat and mass transfer, and the more difficult it is for the moisture inside the material to be transferred to the outside, so the drying time will be longer.
2. Pre-freezing temperature and maintenance time. If the pre-freezing is not well frozen, or the freezing is not solid, the material may appear "boiling" during the sublimation drying in the entry stage, or the surface of the product after freeze-
drying may be uneven, affecting the appearance; if the temperature is too low, energy and time will be wasted . The time required for pre-freezing depends on different specific conditions. As a general rule, however, all parts of the product should be completely frozen.
3. The temperature (or heat supply) of the sublimation interface and the ability of water vapor to escape from the product. The former is mainly determined by the temperature of the separator and the pressure (vacuum degree) of the drying box,
while the latter is mainly determined by the temperature of the sublimation interface (corresponding to the saturation pressure of water vapor) and the partial pressure of water vapor in the box.
In addition to the above factors, there are many factors affecting the freeze-drying process, which need to be analyzed and solved by freeze-drying technicians in a specific situation. At the same time, when purchasing freeze-drying equipment,
purchasers should also choose a manufacturer with profound experience in the development and application of freeze-drying technology such as Bo Yikang, which can also provide a lot of help for the application of freeze-drying technology in the future.
Scope of Application
The lyophilizer is suitable for heat-sensitive and heat-sensitive substances. Such as biological fields: medicines, vaccines, serum, plasma, antibodies, microorganisms, plant extracts, etc. Non-biological fields: food, nanoparticles, colloids, plants, cultural relics, etc.
Contact Person: Ms. Wei