A Kettle Reboiler Heat Exchanger is a type of shell-and-tube heat exchanger used to boil a liquid by heating it with steam or another hot fluid. The liquid enters a large shell (kettle), where heat from the tube bundle causes part of the liquid to vaporize, and the vapor exits through the top. It is commonly used in distillation columns and chemical process plants. https://www.unitedheatexchangers.com/heat-exchanger/Kettle-Reboiler-Heat-Exchanger/