For low-pressure air separation devices, the absolute pressure of compressed air discharged from the air compressor is around 0.6MPa. After compression, the moisture content per unit volume of air increases, causing its moisture content to reach the saturation level corresponding to the temperature at that time. When air flows through an air cooling tower, as the temperature decreases, the corresponding saturated moisture content decreases, and the excess part will precipitate from the gas in a liquid state. This part of the water vapor condenses into water and releases latent heat of condensation, which not only increases the cooling water volume but also raises the water temperature. But the temperature of the air exiting the tower decreases, so although the air comes into direct contact with water in the cooling tower, the moisture content will actually decrease.
For example, with a 3200m/h oxygen concentrator, the processing air volume is 19580m/h, and the absolute pressure of compressed air is 0.59MPa. The temperature of the air entering the air cooling tower is 50 ℃, and the temperature of the air exiting the air cooling tower is 30 ℃. In this case, the amount of water precipitated by the air through the cooling tower can reach 220kg/h.
