Air cooler

All low pressure air separation units are usually equipped with nitrogen water precoolers. It mainly uses the unsaturation of nitrogen in sewage to evaporate part of water. As the water evaporates, it absorbs the latent heat of vaporization to lower the temperature of the cooling water, which is then used to cool the treated air and lower the temperature of the air entering the column. Therefore, it includes air cooling column and water cooling column. The basic purpose of setting up nitrogen precooler is to reduce the air temperature entering the air separation column and avoid the temperature fluctuation greatly. Because the inlet air temperature directly affects the operation conditions of the switching heat ex-changer and distillation column, as well as the economy of the whole air separation unit. In the design, the air temperature entering the column is usually set at 30 ° C. When the inlet temperature of the column is higher than the design index during operation, the throttl

According to a DEAR air separation user, during the operation of a set of air separation plant that has been in operation for 5 years, it is found that under the condition that the inlet guide vane does not change, the expansion air volume of the expander gradually decreases, and the rotation speed of the expander gradually decreases, the outlet pressure of the booster end of the expander rises from 0.76MPa to 0.8MPa, the inlet temperature rises from - 110 ° C to - 95 ° C, and the working condition of the chilled water pump is poor.