In order to vaporize the liquid at the column bottom and send it back to the distillation column, Reboiler is used to keep the reaction going on.
The reboiler for small distillation column has smaller heat transfer area and can be directly located at the bottom of the column. It is generally known as a distillation kettle.
The reboiler for large scale distillation column has large heat transfer area and is located separated from the tower body; They are divided into thermosyphon type and kettle type reboiler.
Thermosyphon reboiler is a vertical shell and tube heat exchanger. The liquid is partly vaporized through the heat exchanger tube, and is heated by the heat carrier in the shell side.
Thermosyphon reboiler with advantages:
However, In order to produce the pressure head needed for liquid circulation, the base of the distillation tower is higher.
Kettle type reboiler usually placed horizontally in the kettle for vapor liquid separation, can reduce the tower height;