In the fractionation tower, the dry point of gasoline is high while the flash point of diesel is low, resulting in overlapping product ranges
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Recently, the hydrogenation refining separation tower has shown a low flash point for diesel, a high dry point for gasoline, as well as product overlap. Hydrogen is used for blowing air at the bottom of the distillation tower, and there are no other heat sources there. I plan to reduce the amount of air blown at the bottom of the tower in order to increase the vapor pressure of the oil and gas at the top of the tower, thereby raising the boiling points of all these substances. Will an increase in boiling points have little effect on the light components, given that their boiling points are already low? Will it have a greater impact on the heavier components? Could the end result be a higher flash point for diesel and a lower dry point for gasoline? ? ? ?
Can hydrogen stripping be used as well? Product overlap is due to insufficient separation accuracy; one should check whether the reflux ratio is sufficient, as well as whether the operating pressure of the tower is too low
This is due to the low internal recirculation within the tower, resulting in poor separation accuracy; simultaneously, the low temperature at the bottom leads to a high degree of overlap among the oils.
A low flash point of the diesel at the bottom of the tower indicates a low initial boiling point of the diesel; therefore, the temperature of the vapor phase at the bottom of the tower should be increased, that is, the heat supply to the reboiler at the bottom of the tower should be raised. A high dry point of the overhead gasoline indicates that the temperature at the top of the tower is too high; too much material is being removed from there. It is necessary to increase the reflux flow at the top of the tower in order to lower its temperature! Additionally, it is necessary to reduce the operating pressure of the tower, which helps to increase the temperature of the gas phase at the bottom of the tower! Haha, let’s go back to reading the book on chemical engineering principles. .
Which edition of the book contains this? I’m not a chemical engineering professional; please recommend one
Raise the gas vapor level and increase the reflux; what are the specifications of the steam, and has the feed volume increased?
It is possible not to use steam in order to control water
Reasons for the too small reflux ratios of the liquid phase at the top of the tower and the gas phase at the bottom of the tower