About the authorMike Fisher has over 35 years of experience with refrigeration systems. This background includes; service, installation, equipment manufacturing, research and development, project management, consulting engineering, system design and packaged systems.
I often see questions about this and wonder what sort of answer someone is expecting. Almost all industrial refrigeration use ammonia as a refrigerant. Although there is a renewed interest in CO2 refrigeration systems, ammonia is the dominant refrigerant by choice. When compared to any other mechanical refrigeration system the basic fundamentals apply.
Since the advent of the mandated Process Safety Management program (PSM) the industrial refrigeration sector has been faced with attempts to maintain lower refrigerant charges (re: inventories of refrigerant used in the system). To date, most of the efforts expended focus on keeping the ammonia refrigerant charge under 10,000 pounds. To a degree, this has largely centered around minimizing the quantity or use of gravity-flooded air-cooling evaporators or flooded shell and tube heat chillers. While these methods will drastically reduce the total refrigerant charge, other methods can be applicable. These typically involve re-thinking the basic premise for the use of a refrigerant and the application of specific sub-systems that are used in ammonia refrigeration systems.
We have worked on several projects with a local contractor where stainless steel was used for the ammonia piping system. One of the most obvious benefits of using stainless steel over carbon steel is the elimination of corrosion. The use of carbon steel piping presents a challenge to work with, even though it has been the most common piping material in use for ammonia refrigeration systems.
