Jacketed kettle reboilers

The function of reboilers has already been discussed. These components are essentially heat exchangers that are used to transfer heat to bring the liquid at the bottom of the column to its boiling point (refer also to discussions in Chapter 1). The principle types employed are jacketted kettles, simple kettle type reboilers, internal reboilers, and thermo-syphon reboilers. Examples of each type are illustrated in Figure 7. 

Distillation normally involves three pieces of equipment a column, a condensor on top of the column, and a reboiler at the bottom of the column. The reboiler, often a steam-jacketed kettle, is heated so that much of its contents evaporate and flow upwards through the column. The vapors passing out of the column are liquefied in the condensor and much of this condensate is sent back downwards through the column. This countercurrent flow of vapor and condensate is common to all forms of distillation. 

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