(Catalytic cracking) Reaction depth and bottom temperature of the fractionation tower
Thread Content
I read a post that mentioned something about the relationship between reaction depth and the temperature at the bottom of the distillation column: the greater the reaction depth, the lower the temperature at the bottom of the distillation column； Is it still the large reaction depth that causes the high temperature at the bottom of the fractionation tower? What are everyone’s thoughts? Feel free to share.
The bottom temperature of the distillation tower is determined by the heat absorbed by the slurry; the more heat absorbed by the slurry, the lower the bottom temperature of the distillation tower. As the reaction depth increases, the load on the lower part of the distillation column decreases; with the heat removal from the oil slurry remaining unchanged, the temperature of the distillation column drops. I’m not sure if this analysis is correct
Those upstairs should note that, under normal circumstances, a similar question comes with an implied condition: all other factors remain unchanged. According to the conditions given by the poster, a greater reaction depth leads to more thorough cracking of the oil products, which results in a decrease in the liquid level at the bottom of the distillation tower and an increase in the temperature at that location (this is also what happens in actual operations)
The reaction depth is large, resulting in a significant amount of heat being carried by the reaction gases to the distillation tower; under unchanged other conditions, the temperature at the bottom of the distillation tower increases.
Agree with the view from floor 4! It’s mainly because of the lots of heat carried over.
I still prefer Building 2#. With other operating conditions unchanged, an increased reaction depth leads to a decrease in the temperature at the bottom of the distillation column.
This post was last edited by jbcyf on 2011-10-10 09:39. It seems there’s no inevitable connection; it depends on your distillation procedures.
Let’s continue the discussion~~~ We can add a sentence after the previous one as follows: Under unchanged other operating conditions, as the reaction depth increases, the temperature at the bottom of the distillation column decreases, and the liquid level at the bottom of the distillation column drops. We know that a large reaction depth causes the liquid level at the bottom of the tower to drop. Isn’t that contradictory?
As the liquid level at the bottom of the distillation tower decreases, it is necessary to increase the amount of slurry that is sent back up the tower; this way, heat is carried to the bottom of the tower, and the temperature naturally rises.
This post was last edited by jbcyf on 2011-10-10 09:40. Increasing the amount of slurry returning to the tower should mean reducing the heat input at the bottom of the tower. Reducing the amount of slurry returning to the tower increases the heat input to the bottom of the tower. Is that how it should be understood?~~~~~~
Increasing the amount of slurry that returns to the tower should mean a reduction in the heat introduced at the bottom of the tower; whereas reducing the amount of slurry returning to the tower would result in an increase in the heat introduced there. Is that how it should be understood? :o:o:o