Refrigerated dryers are the most common type of compressed air dryer. They remove water from the air stream by cooling the air to approximately 3 °C (38 °F) and effectively condensing out the moisture in a controlled environment. A compressed air dryer is a piece of equipment designed to separate water vapor or moisture (de-humidify) from industrial process air. In the typical system, a compressor draws in humid air and compresses it, which raises the air temperature and then cooling the air condensing water vapor out of the unit. Refrigerant drying means that the compressed air is cooled, which allows a large amount of the water to condense and be separated. After cooling and condensing, the compressed air is reheated to around room temperature so that condensation does not form on the outside of the pipe system. This heat exchange between ingoing and outgoing compressed air also reduces the temperature of the incoming compressed air, and as such reduces the required cooling capacity of the refrigerant circuit. Cooling the compressed air takes place via a closed refrigerant system. Smart steering of the refrigerant compressor via intelligent control algorithms can significantly reduce the power consumption of modern refrigerant dryers. Refrigerant dryers are used for dew points between +2˚C to +10˚C and have a lower limit, which is the freezing point of the condensed water. They are available as either a freestanding machine or an integrated drying module inside the compressor. The latter has the advantage of having a small footprint and ensures optimized performance for the particular air compressor capacity. Modern refrigerant dryers use refrigerant gases with a low Global Warming Potential (GWP), which means refrigerant gases that -when accidentally released into the atmosphere- contribute less to global warming. Future refrigerants will have an even lower GWP value, as dictated by environmental legislation. Refrigerant drying means that the compressed air is cooled, which allows a large amount of the water to condense and be separated. After cooling and condensing, the compressed air is reheated to around room temperature so that condensation does not form on the outside of the pipe system.
