What are the reasons for fluctuations in the pressure at the top of the distillation tower, poor distillation efficiency, and high pressure drops?

Check the pressure drop up and down the tower to rule out blockages inside the tower； Check the operation of pressure equipment ； Analyze the impact of the stability of operating parameters on distillation fluctuations. This post was last edited by lxzzl on 2009-3-28 13:00]

Although the original poster mentioned that it is for transporting crude oil, I would like to add that if atmospheric pressure desalination is not effective or if the crude oil contains a high level of salt, it can lead to severe salt deposition inside the distillation tower. This situation has occurred in our factory, and salt buildup can be removed by performing tower washing with water injected at the top of the tower! ! This post was last edited by lxzzl on 2009-3-28 13:01.]

You are using pipeline-transmitted crude oil, and the reasons for pressure fluctuations at the top of the fractionation tower are: 1. Excessive impurities in the crude oil, which cause blockages in the tray； ⒉Crude oil contains high levels of salts, which causes salt deposition on the trays ； ⒊The temperature at the bottom of the tower is too high, or the amount of steam used for stripping is excessive, causing over-pressurization and the displacement of the trays.

1. The crude oil contains too many impurities, which clog the trays； 2. The crude oil contains high levels of salts, which causes salt deposition on the trays ； 3. Check the solid content of the slurry to see if it contains too much catalyst, which could cause blockages; in any case, consider the possibility of blockages in the trays

Reply to LZ: The phenomena you mentioned are caused by salt accumulation on the fractionation pedal and tower blockage. Reason: The main component of the salts present in crude oil is chlorides, and after electrodialysis desalination, a small amount of residual salt still enters the distillation tower. This will cause corrosion of the tower. To prevent corrosion of the equipment due to the hydrolysis of chlorinated water, we often employ anti-corrosion measures such as injecting alkali and ammonia. When too much alkali is added, alkali scale is formed and deposits on the bottom plate of the tower. Ammonium salts are formed after ammonia is injected at the top of the tower; the reflux oil from the tower top returns to the tower and can deposit in the downcomer. Chlorides also decompose at high temperatures to produce ammonium salts. Sediment and other impurities mixed in crude oil will also deposit on the trays of the fractionation tower. This will cause blockage in the tower, leading to fluctuations in the pressure at the top of the distillation column, poor distillation efficiency, and a high pressure drop. The common method to address salt buildup and tower blockage is “water washing”. Fresh water is injected to wash the tower. This post was last edited by Barber on 2009-3-30 12:13]

1 Salt formation. 2 Tray blockage 3 Trapped tower

Check for salt buildup on the trays, and analyze whether the impurities in the raw materials as well as the solid content in the slurry are excessively high.

Check the gas-phase load at the top of the tower, whether salt deposition has occurred on the tray plates, whether the tray plates are damaged, whether the compressor system is functioning properly, and whether the pressure control valves are malfunctioning.

It is recommended to first confirm whether it is a problem with the secondary meter; if there is no issue, the following measures should be taken: 1. Ensure the stability of the temperature at the top of the stabilizer after cooling. 2. Monitor the plate pressure drop to rule out faults in the internal components. 3. Temperature changes in various sections of the pressure increase tower. 4. Monitoring of component and flow rate changes at the top of the tower, as well as monitoring of raw material changes.

Is it due to a clogged downcomer or excessive steam flow causing flooding? Or, if the flow rate of the feed material is too high, the export of the separated components can be accelerated to prevent salt formation