Weekly Topic: Efficiency Improvement of the Crude Argon Column in Distillation Towers
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For venting, the crude argon column and the main column are placed together; liquid nitrogen is used as the cooling source for the crude argon column, with the crude argon being vented directly without any recovery. It’s very difficult to operate this type of crude argon efficiency tower; it often becomes unstable, resulting in a high liquid-air level in the lower section of the tower. Those who have experience with such processes would be able to share their insights. I’d like to discuss the principle behind this tower as well as the key points for its operation.
The general process is as follows: The liquid air passes through the subcooler; part of it goes to the crude argon column to serve as a cooling source before returning to the upper column. The crude argon from the upper column is sent to the crude argon column for distillation, and after that the crude argon gas is sent to the plate exchanger. The argon fraction with a high oxygen content is sent back to the upper column to participate in the distillation process.
Our air separation is very simple; we only need nitrogen, with everything else being removed. There is no apparatus for producing argon.
What the poster is referring to is a performance-enhancing argon column; its purpose is to increase the oxygen extraction rate. Such columns are generally installed in air separation units that do not have an argon system. When did you observe instability? Was it during startup or at some other time? There should be a method for checking the argon content in the argon fraction there – generally, this value is kept low. By controlling the liquid level in that performance-enhancing column properly, everything should be fine. Such systems are very easy to operate; we have several units of this type, and they are easier to manage than those with an argon system
I’ve learned it! ! ! ! ! ! ! !
Exactly! Mine too; it’s very easy to use