Refrigeration systems are a common sight in a lot of business settings but not all are created equal. This is because some industrial activities require temperatures much lower than conventional cooling methods can achieve - activities like pharmaceutical storage and scientific research.
It’s in these circumstances that a cascade refrigeration system comes into play - a sophisticated piece of technology that allows for ultra-low temperature control.
To better understand what a cascade cooling system is, we can compare it to a single-stage system.
In a single-stage system, there is only one refrigeration cycle involved. This works by compressing and expanding a refrigerant to absorb heat from the space being cooled and finds common applications in commercial refrigeration and household appliances.
However, single-stage systems have limitations in terms of how low they can cool - typically achieving temperatures no lower than -40 ℃.
A cascade cooling system uses two or more separate but interconnected refrigeration cycles, with the cold output of one cycle serving as the heat input for the next.
This arrangement allows cascade systems to reach temperatures as low as -80 ℃ or even lower, depending on the specific design and components used.
In a basic cascade system, there are two separate refrigeration cycles, commonly known as "stages” - a high temperature stage and a low temperature stage.
Each stage has its own set of components - including compressors, condensers, expansion valves, and evaporators - and uses a distinct refrigerant. These are selected based on their boiling points, which directly influence the temperature range over which they can effectively absorb or release heat.
The high stage cycle uses a refrigerant capable of cooling a space or equipment down to a moderate temperature level, while the low stage uses a refrigerant that can achieve much colder temperatures.
The key to a cascade refrigeration system is the heat transfer between these two stages.
As the refrigerants pass through their relative cycles, the evaporator of the high stage cools down the condenser of the low stage. This setup allows for efficient heat transfer between the cycles without mixing the refrigerants.
To put it simply - a cascade cooling system works by using the cooling effect of one refrigeration cycle to assist in achieving even lower temperatures in another cycle, allowing for much lower temperatures than would be possible with a single refrigeration system.
Because of their ability to achieve such low temperatures, cascade cooling systems have a number of specialised applications, including:
Medical and pharmaceutical: these systems are crucial for preserving biological samples, vaccines, and medical supplies requiring storage at ultra-low temperatures.
Laboratory research: in scientific laboratories, cascade cooling systems are employed for experiments that demand ultra-low temperatures and precise control, such as research in materials science and chemistry.
Food processing and storage: cascade cooling systems play a vital role in preserving food quality and extending shelf life, used for quick freezing of perishable foods and maintaining cold storage facilities.
Environmental testing: they’re also used in environmental chambers for testing products and materials. Industries such as automotive, electronics and aerospace use cascade cooling systems to assess the performance and durability of their products across a range of extreme temperature conditions.
If you’re a business in the East Midlands looking for advice on cascade cooling systems, Loughborough Air Conditioning can help.
Our experienced engineers are more than happy to talk through your requirements before recommending the most suitable equipment, all sourced from leading manufacturers. We’re also proud to offer first rate installation and after care services.
