Does the top pressure of our distillation unit’s atmospheric tower sometimes show as negative on the DCS? ?
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This post was last edited by Final Fantasy on 2010-7-24 20:04. The pressure at the top of our distillation column under atmospheric conditions sometimes shows as negative on the DCS system. Do you think it’s possible for the pressure at the column top to be negative? ? ?
It shouldn’t, we’ve never encountered a situation like that. Suspect there is a problem with the instrument
It’s impossible; there must be a problem with the instrument or the DCS module.
The reason for the formation of negative pressure is that at low processing rates, the pipe diameter is relatively large resulting in lower resistance. The oil and gas coming out of the top of the tower are entirely in gaseous form, at high temperatures and occupying a large volume; after being cooled by air condensation, their volume decreases rapidly, thereby creating negative pressure. The minimum value of this negative pressure occurs at the constant-pressure reflux tank
It’s unlikely; it’s probably a problem with the instrument or the DCS module. It is recommended to check the low-pressure gas system to confirm.
Instrumentation issues are the most likely cause, but other operational or process-related problems cannot be ruled out either; let’s start by checking the instrumentation first
The phenomenon you mentioned has not occurred; it’s likely a problem with the instrument.
Zero drift. . . Or the selection was incorrect. . . The main line for the oil and gas at the top of the atmospheric pressure tower is connected directly to the reflux tank after being cooled by air or water; the reflux tank operates at atmospheric pressure (with the gas being released directly or used as fuel in a furnace) or at slightly positive pressure (when the gas is recovered), so it is not under negative pressure. . . :lol
Is there another reason why it often gets pushed into the compressor? If it’s entered, it’s possible to get a negative value displayed!
The compressor recycling of normal overhead gas and reduced overhead gas results in negative pressure at the top of the atmospheric tower, which is a design flaw. . . The diameter of the atmospheric pressure tower is designed for normal pressure conditions; if negative pressure is applied, the operation of the tower will be disrupted. . . :lol