What does the term "heat exchanger" refer to in boiler systems?

The term "heat exchanger" in boiler systems refers to a device specifically designed to transfer heat between two fluids without allowing them to mix. This is a crucial function in many industrial processes, including heating systems, power generation, and refrigeration. The primary purpose of a heat exchanger is to efficiently transfer thermal energy from one fluid (which can be a liquid or gas) to another, ensuring that the fluids remain separated to prevent contamination or unwanted chemical reactions.

Heat exchangers are used in various applications, such as preheating feed water before it enters a boiler, condensing steam back into water, and even cooling hot fluids. Their design can vary widely, with common types including shell-and-tube, plate, and air-cooled heat exchangers, each serving specific operational requirements.

While mixing fluids can happen in different equipment types, the heat exchanger's defining feature is its ability to transfer heat effectively, which enhances system efficiency while maintaining the integrity of the fluids involved.