Lesson 8 - Heat Exchangers
This lesson focuses on the two main heat exchangers found in breweries, namely plate heat exchangers and shell and tube heat exchangers. The lesson will examine the components, assembly, and operation of these exchangers. It will also discuss how to select and size a heat exchanger and the considerations for cleaning, maintaining, and operating heat exchangers in the brewing process.
Shell and Tube Heat Exchangers
Sometimes, the limitations of plate heat exchangers make them unsuitable for certain brewing applications. In this section, we will learn about the components, assembly, and design of another heat exchanger used in brewing - the shell and tube heat exchanger.
In its simplest form, the shell and tube heat exchanger is a single pipe or tube inside another pipe. In industrial applications, a shell and tube exchanger consists of many tubes grouped together and housed inside a large cylindrical pipe, as seen in the figure below.
Figure: Typical shell and tube exchangers of various size
While no longer as popular across brewing as the plate heat exchanger, shell and tube exchangers have some unique features that make them more suitable for certain applications, in particular wort boiling and utilities. These include:
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Ability to handle a wide range of fluids, pressures, and temperatures, making it very versatile
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Low pressure drops
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Well suited for high-fouling fluids
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A simple design that is robust and low maintenance
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Low capital and operating costs