Fluctuations in the level gauge curve of the liquid separation tank
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This post was last edited by zyzs on 2018-10-26 at 16:18. It’s a curve showing the level of a liquid separation tank; it started fluctuating as soon as it was put into automatic operation. Previously, the curve was a basically straight line, and the process engineers said that the PID parameters hadn’t been changed – so why did this happen? The transmitter is of the float type, and the valve is a pneumatic control valve. The medium is sulfur-containing wastewater. Pressure of 0.5 MPa, temperature around 40 degrees. The locator was also replaced, and the valve was taken apart for inspection – everything seems fine. The table was also observed to be synchronized with surface elevation changes. That’s strange. If nothing else works, the float must be removed and a new transmitter installed. (Solved, the reason is on the 11th floor)
It’s the same whether it’s used locally or remotely; what’s the point of replacing it with a float level gauge?
I think this level of fluctuation is okay; can’t the rear part be operated properly?
As long as it fluctuates within the normal range (i.e., within the operational flexibility range), there should be no problem. Is the pressure also fluctuating?
The pressure doesn’t fluctuate; these fluctuations can be controlled now. The fluctuations used to be greater than this; now, for some reason, they have become less severe.
It can be controlled now, but before it moved in a smooth straight line; I don’t know why it started to fluctuate like this. The fluctuations used to be more severe and frequent than they are now.
A liquid separation tank is used to separate wastewater from what other materials? .
Personally, I still think this falls within the normal range of fluctuations; since it doesn’t affect the subsequent processes, there’s no need to worry about it! How can everything be a straight line? If everything is so straight, aren’t you worried? :lol
This post was last edited by zyzs on 2018-10-26 at 16:17; the reason must have been found. It is because the process liquid level is always kept at 45%; perhaps scale has formed on the float at that point, or something has stuck there and won’t come off. So automatic control is not good at this point; it’s better to use a setting of 55%. Later, the buoy was cleaned with steam until clean water was discharged, and after adjusting it back to 45%, normal operation was observed as well.