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.
Preface
Refrigeration is essential to the operation of a brewery.
As we learned in the Refrigeration Theory lesson, refrigeration is essentially a process that removes heat from one area or material (at low temperature) and rejects it to another area, which is referred to as a ‘heat sink’. When we refer to primary refrigeration, we are normally referring to mechanical refrigeration. Mechanical refrigeration utilises the vapour compression cycle.
The primary refrigeration process utilises the phase changes in a substance to generate refrigeration. Although this can be used directly, primary refrigerants can be used to cool secondary refrigerants, and these secondary refrigerants can be used to carry out the actual cooling in the brewery. This process only relies on heat transfer, rather than on the phase changes of a substance to instigate the cooling. We can thus differentiate between primary and secondary refrigerants. There are many refrigerant choices, and we must evaluate them carefully to ensure that we choose the most suitable option for our brewery’s particular circumstances.
Before we delve into the technology, let’s first consider the different refrigerants available.