How Compressors Get Rid of Water Vapour

People who are planning to hire air compressors need to pay attention to how those compressors remove water vapour from the air used during various applications. This article discusses the common ways of extracting water vapour from compressed air.

Refrigerated Dryers

Compressors can get rid of water vapour by lowering the temperature of the air so that any moisture within it can turn into a liquid. The liquid water is then removed by the condensate trap in the compressor. The air is heated again so that it reaches the point of use when it is at the same temperature as it was when it entered the compressor. One key advantage of refrigeration dryers is that you can avoid the costs that are associated with renewing the drying system. However, the dryer still uses energy to reduce the temperature of the air in order to convert the vapour into liquid water. Furthermore, refrigerant dryers aren't suitable for applications where high purity is required because some water vapour can still remain within the air provided by the compressor.

Desiccant Dryers

Another way to get rid of water vapour from compressed air involves passing the air over desiccants. The desiccants absorb the vapour and dry air exits the equipment. This method is ideal for applications where air should be free from any trace of moisture. However, desiccant dryers can increase your operational costs because you may use more energy to heat air in order to remove the moisture that has accumulated within the desiccants. Secondly, the desiccants have to be replaced periodically because they have a finite service life. You also have to use more energy to operate your compressor because the pressure of the air drops as it passes over the desiccants. Higher-pressure settings result in higher energy use. Caution should also be taken when using desiccant dryers because the moisture which is trapped within the desiccant media can be a breeding ground for mould and other pathogens. One must therefore regenerate the desiccant at the end of the day so that moisture isn't left to shelter microorganisms.

Drying compressed air has costs that can add up over time. Some of these costs can be reduced by working with compressor hire firms to select equipment with an affordable cost of drying the air. For example, you can opt for a compressor that depends on a heater and a blower to extract the moisture from saturated desiccants. This will save some of the energy that would have gone to heating the air in order to make the water evaporate.