In the air separation equipment, the air cooling tower and water cooling tower are supporting cooling equipment with similar structures, but there are obvious differences in working medium, purpose of action and source of cooling source, with clear division of work and mutual cooperation.
First, different working media. The heat exchange medium of the air cooling tower is compressed air and circulating cooling water, and the compressed air is mainly treated; The heat exchange medium of the water cooling tower is circulating water and low-temperature sewage nitrogen, mainly cooling circulating water.
Secondly, different working roles. The air cooling tower is mainly used to cool the high-temperature compressed air discharged from the air compressor, reduce the air temperature, wash the dust and oil in the air, purify the air and provide qualified air intake for the molecular sieve. The water cooling tower mainly cools the high-temperature return water after the air cooling tower is used, so as to realize recycling of circulating water and save water resources.
Third, the cold sources are different. The air cooling tower relies on the cold water cooled by the water cooling tower to complete heat exchange; The water cooling tower uses the low-temperature dry nitrogen discharged from the air separation rectification tower as the cold source, and uses the evaporation and heat absorption to reduce the water temperature.
Fourth, different process locations. The air cooling tower is located behind the air compressor and in front of the molecular sieve; The water cooling tower belongs to the circulating water cooling system and is independently matched. To sum up, the cooling air of air cooling tower and cooling water of water cooling tower cooperate to ensure stable temperature and economical operation of air separation system.
