Why is the temperature of the contaminated nitrogen gas at the top of the tower so low?
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Why is that? Please ask the master to explain it in more detail, would that be okay?
The saturation pressure determines the saturation temperature; since the pressure in the upper column is low, the temperature of the WN exiting it is also low. This is why nitrogen from the main cooler can evaporate oxygen.
1. There is also heat release from Air Liquide in the upper tower; 2. It makes sense for it to be on the 2nd floor
The temperature inside the distillation tower is affected by pressure and product purity; the lower the pressure, the lower the temperature, and the higher the nitrogen purity, the lower the temperature
Hehe, actually this question is quite simple. The change in pressure you’re referring to isn’t due to a decrease in gas temperature; rather, it’s necessary to consider the cooling process. For example, if an air separation unit only has an expansion machine and pipes, without a throttle valve, then the outlet temperature of the expansion machine can remain at -173 degrees. No matter how the pressure changes, the temperature in the tower will be only higher than -173 degrees. The reason why the temperature of the nitrogen is so low is because of the use of liquid nitrogen for cooling – the liquid nitrogen passing through the subcooler can reach -183 degrees, and after passing through the throttle valve, the temperature can drop to -193 degrees, which is why the nitrogen temperature is low
At saturation, the liquid temperature is the same as the gas temperature. Think about the temperature of liquid nitrogen at the top of the tower