The effects of moisture in the pneumatic system
Intake air contains water vapour
The air your compressor draws in contains water vapour. Depending on the relative humidity and temperature, this can vary from 2 grams of water vapour per m³ of ambient air on a cold winter day to 30 grams per m³ on a hot summer day.
During compression, the water vapour concentration is increased 8 to 9 times. The warm air cools in your compressed air boiler and already excretes some water vapour as condensation. At lower temperatures, less water vapour can remain dissolved in the compressed air. Still, water vapour remains behind, which can cause damage if not removed.
Condens causes failures
Condens in your pneumatics system causes failures. Even with a refrigeration dryer, compressed air is not dried sufficiently at temperatures below 7°C. Condensation still forms, affecting the lubrication of the cylinder. This leads to damage to the piston rod seal and can disrupt the operation of gates, requiring immediate repair.
Frozen condensation causes parts to refuse
When moisture freezes, valves and cylinders no longer function. This also affects lubrication. Electric valves sometimes stop switching after frost because ice blocks the slide in the valve. After defrosting, the valves seem to work fine, but moisture remains a problem.
Dry air is therefore essential!
Which dryer should I choose then?
The most important question when choosing a compressed air dryer is, "How cold can the compressed air in the system get?" Less water vapour can be absorbed at lower temperatures, which is why the dew point is important. The dew point is the temperature at which water vapour condenses.
There are several methods of drying compressed air. However, several dryers cannot withstand low temperatures. For the agricultural industry, we recommend the MelQ adsorption dryer.
This is how the adsorption dryer works
Pressurised air flows over an adsorbent that removes water vapour. Two drying columns alternate between drying and regeneration. This system can reach dew points of -40°C and does not rely on purge air. It requires less purge air and energy, and is easy and cheap to maintain. This robust system is ideal for operating temperatures below 4°C and environments with less attention and knowledge, such as farms. This is why MelQ selected this system for the agricultural market.
What can MelQ do for you?
Would you like to know what MelQ can do for you? Get in touch with your local dealer or one of our technical specialists, they will be happy to assist you.
