Lesson 9 - Refrigeration Technology SAQ
This lesson allows you to test yourself on the material covered in the Refrigeration Technology lesson and determine the level to which you have met the learning outcomes.
Suggested Response - Q3
** Your manager wants you to replace your brewery’s ammonia refrigeration plant with another less toxic gas. What would your arguments be for keeping the ammonia plant?
Response:
Points in favour of using ammonia rather than another less toxic gas include:
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Whilst ammonia is classified as highly toxic, its pungent odour makes it readily detectable at low (non-toxic) concentrations. Any small leaks can be readily detected.
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Ammonia is only flammable in high concentrations and you are not likely to experience these concentrations in a brewery environment.
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Ammonia is lighter than air, so any leaks will disperse.
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Ammonia has an ODP of 0 and a GWP of 0, so it is environmentally friendly.
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It readily dissolves in water, which means that a water spray can be used to control a leak. If using this method we must ensure the water used to contain the ammonia leak is prevented from entering a watercourse.
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It operates at desirable pressures and temperatures, and has a relatively high COP.
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It is inexpensive compared to the synthetic refrigerants.
Thus, aside from its toxicity, ammonia performs well in all other measures and can be used as an effective refrigerant.