What should be done if the temperature at the top of the stripping tower doesn’t rise?

There are two ways to increase the temperature at the top of the hydrodesorption tower: 1. Reduce the reflux flow at the tower top or the amount of material fed into the tower; 2. Increase the steam supply to the reboiler at the bottom of the tower

Is there too much reflux? Is the reflux containing water? Is your column pressure too high? Pay close attention to these things.

Everything is controlled according to the process parameters; the reflux level falls within those parameters. When the amount of gas injected increases, the top temperature remains stable and does not rise any further. Is this related to the design of the tower?

I have a different view: A 1-stage hydrodesorption column is generally operated in full reflux mode, and if the properties of the feed change, it becomes impossible to control the temperature at the top of the column. Is the temperature of the 2 tops low? What is the reason? Is it caused by high backflow, or by a low vapor phase at the tower top? To be verified. 3 Is the stripping steam low? Is it the steam? Is it the low feed temperature that causes steam to condense, resulting in a reduced stripping effect and consequently a lower top temperature of the tower? 4. Is it also possible that the feed inlet of the tower is too low, resulting in poor vaporization efficiency and an inability to make effective use of the upper trays in the tower? 5. Water carried back by the reflux stream, or water present in the feed, can lead to an excessive cooling load; such water-containing reflux can cause instability in the tower pressure. Water has a much higher specific heat than oil, and it carries away more heat, leading to waste of heat within the cooling system. This is just my personal opinion; please correct me if I’m wrong. Thank you.

It certainly affects the distillation efficiency of the distillation column, leading to a low flash point of the naphtha. The amount of gas vapor can be reduced or the feed temperature increased, as well as the reflux volume.

It seems that your situation is largely related to the pressure of the operation

1. Is the feed too heavy? 2. Is the feed temperature too low? 3. Is the feed volume too small? 4. Is the bottom temperature too low? 5. Is the reflux rate accurate, or is it too high? 6. Is the reflux temperature too low? 7. Is the top pressure too high?

4# 510053496 Sometimes the process parameters cannot be trusted entirely; if the MATERIAL BALANCE is incorrect, there may also be discrepancies in the process package. When problems arise while operating according to the process parameters, you can try empirical methods to make adjustments, such as reducing the backflow rate or increasing the steam supply, as mentioned above. Or you can check whether the process conditions have changed, resulting in deviations in the results.

This post was last edited by Zhongyuanren on 2009-12-13 23:38. The reasons are: 1. There are too few light components in the feed mixture； 2. The feed temperature is below the bubble point ； 3. Is the amount of stripping steam or nitrogen too low? ； 4. The temperature at the bottom of the tower is too low ； 5. The backflow volume is too large ； 6. Excessive water content in the raw materials ； 7. The tower top pressure control is too high. 8. Severe salt deposition on the tray or blockage by debris ； And other reasons. Carefully analyze and address the issues, taking concrete action.