Lesson 8 - Refrigeration Technology
This lesson takes a closer look at refrigeration technology. It reviews the different primary and secondary refrigerants and explores the technology required to deliver primary refrigeration to the brewery. It concludes by looking at how refrigeration is used within the brewery.
Compressors
Compressors are the work horses of the refrigeration plant. They use the majority of the total energy used in the refrigeration process. Compressors need to be operated and managed well in order to ensure that the refrigeration process is as energy efficient as possible. The two main types of compressors used for industrial refrigeration are screw compressors and reciprocating compressors.
Compressors can be hermetic, which means that the motor is sealed in with the compressor so that no leaks can occur. This is typical in smaller installations, e.g. your refrigerator at home. Semi-hermetic compressors still have enclosed motors, but they have some separation from the working parts. Open compressors mean that the motor is outside the housing. The compressor itself still has to be enclosed, otherwise you won’t achieve any compression!
Compressors can be air-cooled, water-cooled or oil-cooled.
We can also distinguish between single-stage and two-stage compressors. Two-stage compression means that the output of one stage of compression feeds the next stage of compression. We will elaborate on this later in the lesson.
In the next few pages, we will take a look at the details of screw and reciprocating compressors.