Laboratory vacuum freeze drier (
Hereinafter referred to as the lyophilizer, lab freeze-drying machine, small lyophilizer)
, is to realize the freeze-drying technology equipment, the lyophilizer involves refrigerating, vacuum, thermal, mechanical, fluid, electric control and knowledge in the field of pressure vessel and so on.
Users in the freeze-dried unit of choose and buy, therefore, often will encounter many problems, the lyophilizer small make up in the user's point of view, summarize freeze-dried unit of choose and buy should pay attention to several parameters
1, freeze-dried area
users according to their own needs (
The capacity of a day)
, how to determine the required freeze-dried area of the lyophilizer.
2, temperature of cold trap
the temperature of cold trap lyophilizer lab mainly include -
About 45 ℃, -
About 60 ℃, -
A few class such as around 80 ℃.
Temperature for - cold trap
45 ℃ lyophilization is suitable for some easy freeze-dried products, cold trap temperature for -
About 60 ℃ the lyophilizer is suitable for most of the freeze-dried products, cold trap temperature for -
80 ℃ of freeze-dried lyophilization is suitable for some special products.
in the case of no special requirements, selection of temperature, cold trap
About 60 ℃ is the ideal choice.
3, cooling rate
cooling rate reflects the refrigeration capacity of refrigeration system.
For example, the temperature of cold trap & le;
-
60 ℃ the lyophilizer, open the refrigeration machine start timing, cold trap - temperature is reached
1 hour should be no greater than 60 ℃.
4, ultimate vacuum
ultimate vacuum of the lyophilizer leak and vacuum extraction efficiency.
The vacuum degree should be within a reasonable range.
Vacuum degree is too high, which is unfavorable to heat transfer, the drying speed dropped, but no matter how limiting vacuum of the lyophilizer no-load should reach more than 15 pa.
5, vacuum time
no-load time speed, freeze-drying box should be in half an hour from atmospheric pressure to 15 pa.
6, plate layer temperature uniformity and smoothness:
layer plate temperature uniformity and flatness, uniformity has a great influence on the quality of products, the better the temperature uniformity and smoothness of the lyophilized product quality uniformity is, the better.
7, control system
the lyophilizer control system of type and different function, the control system can be real-time display the lyophilization process parameters and automatically record;
Setting, modify, and effectively perform freeze-drying process;
Have the communication interface for data acquisition, preservation.