The Cold Dryer is the abbreviation of the freeze dryer, the cold dryer is the introduction of new technology, belongs to the pneumatic system in the air source treatment components. Heat is exchanged between the refrigerant and the Compressed air to reduce the Compressed air temperature to a dew point temperature in the range of 2 to 10 °C. According to the principle of freezing and Dehumidification, the heat of the Compressed air is exchanged through an evaporator, compressed Air condenses gaseous water into liquid water, which is discharged from the machine through a gas water separator. Heat is exchanged between the refrigerant and the Compressed air to reduce the Compressed air temperature to a dew point temperature between 2 °C and 10 °C