What are the causes of the lower tower liquid level indication fault?
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This post was last edited by you*n*nyou on 2011-9-5 21:59. There is a malfunction with the liquid level indication in the lower column of the low-pressure internal compression process distillation tower (main tower); the liquid level fluctuates greatly and the indication is too high. The liquid level transmitter has been checked and is functioning properly. Seeking advice. If the instrument is fine, then it might be: 1. There is a leak in the pressure guide tube of the upper valve; check for leaks and fix them. 2. The pressure guide tube is blocked; disassemble it and clear the blockage. 3. The readings are accurate but there is an issue with the adjustment. Last edited by chc1125 on 2008-11-12 14:40.]
This phenomenon occurs when gasification is unstable. Generally, air separation towers are equipped with heating elements at the bends of the pressure tapping points in the normal phase to ensure complete vaporization of the liquid phase; check for current to confirm that the heating elements are functioning properly. Additionally, positive-pressure tapping ports usually have two outlets; try replacing them to see if it works properly. I used to encounter this problem often too; sometimes just opening the positive pressure exhaust pipe and blowing into it would fix it.
You can use a nitrogen cylinder to back-blow the negative pressure tube. I encountered this problem before as well – liquid got into the negative pressure tube.
Check the pressure tap: verify whether the positive and negative pressures are normal and whether there is air present, as well as whether the positive pressure is higher than the negative pressure. If there is no air, it could be that the pressure tap is blocked or broken. If all these aspects are normal, then the issue lies with the operating conditions or the liquid-air valve