The polluted nitrogen in the water cooling tower is to cool the water, so how does the polluted nitrogen cool the water?

Water cooling tower is a kind of mixed heat exchanger. From the air cooling tower of the nitrogen machine system, the higher temperature of the cooling water (35 ° C), the downward activity of the spray from the top, the lower temperature of the dirty nitrogen (27 ° C) from the bottom up of the switching heat exchanger, the two straight touch, both heat and mass transfer, is a relatively complex heat transfer process. On the one hand, because the temperature of water is higher than the temperature of polluted nitrogen, there is heat directly from water to polluted nitrogen, so that the water is cooled; On the other hand, because the pollution nitrogen is relatively dull, the relative humidity is only about 30%, so the water molecules can continue to transpiration and disperse into the pollution nitrogen. Water transpiration needs to absorb the latent heat of vaporization, taking heat away from the water, so that the temperature of the water is constantly falling. This appearance is like a cup of hot water in the air to cool, hot water and air touch, on the one hand, the heat directly (or through the container wall) to the air, on the other hand, in the steam, the molecular transpiration of water dispersed into the air and take away the heat (latent heat of vaporization), so that the hot water continues to cool, to cool. It is necessary to point out that the moisture absorption of sewage nitrogen is the main factor to cool water, so the relative humidity of sewage nitrogen is the key to affect the cooling effect. This is also the reason why the nitrogen machine system may show that the cooling water outlet temperature is lower than the pollution nitrogen inlet temperature.