1. Freeze dried area

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

2. Cold trap temperature

A cold trap is a device that captures water during the freeze-drying process. In theory, the lower the temperature of the cold trap, the stronger the water harvesting ability of the cold trap. However, the lower the temperature of the cold trap, the higher the refrigeration requirements, and the higher the machine and operating costs. The cold trap temperatures of the experimental series of freeze-drying machines mainly include -60 ℃, -80 ℃, and so on. The freeze-drying machine with a cold trap temperature of -60 ℃ is suitable for the freeze-drying of most products, while the freeze-drying machine with a cold trap temperature of -80 ℃ is suitable for the freeze-drying of some special products. The experiment on the effect of cold trap temperature on water harvesting capacity shows that the cold trap temperature decreases from -35 ℃ to -55 ℃, and the water harvesting capacity is significantly improved. Therefore, in the absence of special needs, choosing a cold trap temperature of around -60 ℃ is an ideal choice.

3. Cooling rate

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

4. Extreme vacuum degree

Evacuation speed of freeze-drying box with no load

5. Control system

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

6. Cold trap capacity

The cold trap capacity of the freeze-drying machine determines the number and volume of freeze-drying samples that can be accommodated. Select the appropriate cold trap capacity according to the needs of the laboratory.

7. Dimensions and weight

Consider the size and weight of the freeze-drying machine to ensure it can adapt to the space and equipment requirements of the laboratory.