1. Freeze dried area

Calculate the appropriate freeze-drying machine area based on the items that need to be freeze-dried to meet the freeze-drying capacity.

2. Cold trap temperature

A cold trap is a device used in the freeze-drying process to capture water. In theory, the lower the temperature of the cold trap, the stronger its water capturing ability. However, a low temperature of the cold trap requires high refrigeration requirements, resulting in high machine and operating costs. The cold trap temperature of the experimental series freeze dryer is mainly around -60 ℃, -80 ℃, etc. The freeze dryer with a cold trap temperature of -60 ℃ is suitable for freeze-drying most products, while the freeze dryer with a cold trap temperature of -80 ℃ is suitable for freeze-drying some special products. The experiment on the effect of cold trap temperature on water capture capacity shows that when the cold trap temperature decreases from -35 ℃ to -55 ℃, the water capture capacity is significantly improved. Therefore, in the absence of special requirements, choosing a cold trap temperature of around -60 ℃ is an ideal choice.

3. Cooling rate

The cooling rate reflects the refrigeration capacity of the refrigeration system. Under no-load conditions, the temperature of the cold trap should reach the minimum temperature specified in the index within 1 hour.

4. Extreme vacuum degree

Evacuation speed of freeze-drying box without load

5. Control system

The control system should be able to display real-time freeze-drying process parameters and automatically record them; Set, modify, and effectively execute freeze-drying process procedures; Equipped with communication interfaces for easy data collection and storage.

6. Cold trap capacity

The cold trap capacity of the freeze dryer determines the quantity and volume of freeze-dried samples that can be accommodated. Select the appropriate cold trap capacity according to the needs of the laboratory.

7. Size and weight

Consider the size and weight of the freeze dryer to ensure it can meet the space and equipment requirements of the laboratory.