Does reducing the top reflux affect the bottom temperature of the tower?
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Does reducing the top reflux affect the bottom of the tower temperature? Why?
It mainly affects the column pressure; when the column pressure changes, the vaporization rate of the medium at the bottom of the column changes, which in turn affects the temperature at the bottom of the column.
For a typical distillation column with single feed, single heat source, and single reflux, when the feed and the heat source remain unchanged, reducing the reflux at the top of the column lowers the total heat absorbed by the column; as a result, the temperatures throughout the column increase. The temperature at the bottom of the column will also rise, but the extent of this increase is limited.
For a typical distillation column with single feed, single heating, and single reflux, when the feed and heating conditions remain unchanged, reducing the reflux at the top of the column increases the output at that point. Meanwhile, a decrease in the reflux rate facilitates smoother gas flow within the column, allowing the pressure at the bottom of the column to be reduced. This lower pressure leads to an increase in the amount of vaporization that occurs, resulting in a temporary drop in temperature at the bottom of the column and an increase in temperature at the top. Since the feed and heating remain unchanged, the temperature inside the reactor will rise slightly, and the system will establish a new gas-liquid equilibrium, of course within the operational flexibility range of the system.