Which statement best characterizes a heat exchanger in a nuclear plant?

• A. A device used to transfer heat from one medium to another; steam generators and condensers are examples.
• B. A device that stores heat within a reactor core for a short time.
• C. A component that generates electricity directly from heat.
• D. A device that cools gas using liquid nitrogen.

Answer: (A)

Heat exchangers move heat from one fluid to another without mixing the two streams. In a nuclear plant, their job is to transfer the reactor’s heat to a secondary loop so steam can be produced to drive turbines. Steam generators are classic examples of heat exchangers, taking heat from the reactor coolant and transferring it to the feedwater to create steam. Condensers are another heat exchanger type, removing heat from the steam after it leaves the turbine and turning it back into liquid water.

This description matches what a heat exchanger does in practice. It’s not about storing heat in the reactor core, nor about generating electricity directly from heat, nor about cooling gas with liquid nitrogen. Those roles are fulfilled by other components or systems, while a heat exchanger’s primary function is to transfer heat between two separate media.