A refrigerant air dryer performs the essential function of removing water vapor and the contaminants it carries from compressed air. Quincy’s refrigerated air dryers purify compressed air by chilling it to approximately 37 degrees Fahrenheit. This process causes moisture to condense. Condensed moisture carries airborne dirt and oil to the separator, where an automatic drain removes it from the air stream. We offer a wide selection of state-of-the-art air compressor dryer products, including non-cycling, cycling, variable speed, and compact high-temperature dryers for many industrial applications.
How Do Refrigerated Dryers Work?
Atmospheric air will always have some level of moisture in it, and compressed air can also have invisible particles of dirt and oil, which may damage your air tools and machinery. The normal pressurization process heats the air, often to around 100 degrees Fahrenheit. High temperatures force the vapor to condense and form liquid droplets, which may harm your equipment. Air treatment including filters and refrigerated dryers solves this problem, extracting moisture to produce clean, dry air.
Here’s how refrigerated dryers work.
- Air enters the refrigerator and travels to an air-to-air heat exchanger. Here, the outgoing cold air pre-cools the warm air.
- Next, the air enters a refrigerant-to-air heat exchanger, which cools it to around 37 degrees Fahrenheit.
- The water droplets separate from the cold air, and the unit expels the moisture. Draining also removes dirt and oil.
- Finally, the air passes back through the air-to-air heat exchanger. The incoming warm air reheats the cooled air leaving the air dryer. The newly dried air has a pressure dewpoint somewhere between 35 and 50 degrees Fahrenheit. See specifications for each Quincy model to find out the exact dewpoint for a particular dryer.
Types of Refrigerated Dryers
Refrigerated dryers generally fall into two categories: cycling and non-cycling dryers.
- Non-cycling dryers: In a non-cycling dryer, the refrigerant circulates throughout the system at the same rate, regardless of the load of the air entering the dryer. Because ambient air temperatures and compressed air flow fluctuate, a hot gas bypass valve regulates the temperature to prevent the machine from freezing. Non-cycling dryers work best paired with rotary screw air compressors.
- Cycling dryers: A cycling dryer cycles on and off in response to the air entering the machine. This type of dryer stores cold energy until a needed time, which helps conserve energy. Cycling systems typically sense when the inlet air mass reaches a specified temperature. The system will then turn on and cool the air until it reaches the desired low temperature. After it achieves this temperature, the system automatically turns off. Since these systems only use the amount of energy required to cool the inlet air, they are even more efficient.
- Variable speed dryers: Variable speed dryers are the most energy-efficient dryers in the market. These dryers speed up or slow down based off incoming air demand. Because they are not constantly running at full flow and only operating at the capacity required at any given time, no energy is wasted. Also, variable speed technology allows for a constantly stable dew point even in harsh environments.
When deciding which type of refrigerated dryer is right for your facility, it’s essential to weigh initial cost and lifetime cost. Non-cycling dryers will be the most affordable upfront. Cycling and variable speed dryers, on the other hand, save on energy costs over time. All work well for most manufacturing applications.
Benefits of Refrigerated Dryers
There are many excellent advantages of refrigerated dryers.
- Ideal for moisture-free applications
- Avoid corrosion to your systems caused by moisture
- Prevent rotting in woodworking applications
- Extend the life of your compressor
- Low maintenance
- Save on energy and upfront costs