Similarities and differences between low temperature freeze dryer and adsorption dryer
In modern industrial production, the use of compressed air is becoming more and more common. Common compressed air dryers mainly include adsorption dryers and refrigerating dryers. What is the difference between a cryogenic freeze dryer and an adsorption dryer?
1. Different working principles
The cryogenic freeze dryer is based on the principle of freezing and dehumidifying, and the saturated compressed air from the upstream is cooled to a certain dew point temperature by heat exchange with the refrigerant, and a large amount of liquid water is condensed, and is automatically discharged out of the machine after being separated by the gas-liquid separator. Achieve the purpose of drying water. The suction dryer is based on the principle of pressure swing adsorption, and the saturated compressed air from the upstream is contacted with the desiccant under a certain pressure, and most of the water is adsorbed in the desiccant, and the dry air enters the downstream work. Thereby achieving the purpose of deep drying.
2. The difference in water removal effect
Because of its principle, cryogenic freeze dryers can freeze if the temperature is too low, so the dew point temperature is usually 2~10 °C. The dryer is because it does not have to pass the temperature change, and the desiccant (alumina) can be further dried. Therefore, the dew point of the outlet can usually reach below -20 ° C, which means deep drying can be achieved.
3. Difference in energy loss
For the low-temperature freeze dryer, since the cooling is performed by the refrigerant compression, the power supply power is high. Since the suction dryer only controls the valve through the electric control box, the electric power is usually only about several tens of watts, that is, there is no power loss.
4. Difference in gas loss
The low-temperature freeze dryer achieves the purpose of removing water by changing the temperature, and the water is discharged outside the machine through the automatic drainer, and there is no loss of gas volume. The dryer is required to regenerate after the desiccant is saturated with water, so it needs about 12-15% of regeneration gas loss.
5. Difference in failure rate
The refrigerant system and air system of the low-temperature freeze dryer include relatively complicated electrical parts, while the dryer only has the possibility of failure due to frequent movement of the valve, so under normal circumstances, the failure rate of the dryer is lower than that of the dryer. .