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Have you noticed or heard anyone complaining about water in the compressed air system or about leaks in the compressor? In fact, this situation is quite common, but we must not ignore it, as it can damage your compressed air system and compromise the quality of the final product. Why does water appear in the compressor system? Water condensation occurs naturally and is a byproduct of compressed air. The amount of water generated by an air compressor depends largely on the inlet conditions, namely the quality of the ambient air and the pressure in that environment. In short, air temperature, humidity, compressor size, and required pressure will determine the water content that comes out of the device and may enter the compressed air pipeline. Of course, humid air contains a higher level of moisture than cold air, which will result in more water flowing out of the compressor. The process of removing moisture from compressed air systems: Today, I’d like to share with you several methods that can be used to eliminate water and moisture from compressed air. I. Over-compression: Increasing the pressure to a level higher than the required pressure for compressed air. At higher pressures, the water droplets will be removed. In the next step, reduce the pressure to the desired compressed air pressure. Starting from this stage, as the relative humidity drops below 100%, only water vapor remains in the compressed air. II. Cooling: Because the compressed air is cooled to a lower temperature. At these lower temperatures, the relative humidity exceeds 100%, and water droplets form. Those water droplets are collected and removed. In the next step, the temperature of the compressed air rises again. Starting from this stage, once the relative humidity drops below 100%, only water vapor remains in the compressed air. III. Adsorption drying: In this method, moisture is removed using a substance with absorptive or adsorptive properties. Through absorption, water is absorbed into a hygroscopic liquid or powder. Moisture adheres to this material; it needs to be removed and replaced with new material for further processing. Through adsorption, moisture is captured by the hygroscopic beads. Water molecules enter the pores through diffusion and accumulate through physical bonding and capillary condensation. In this case, when the beads become saturated, they must be regenerated before they can start adsorbing again. Regeneration can be achieved by heating the magnetic beads or supplying dry air above them. In both cases, the water-retaining capacity is disrupted and water molecules are removed. For example, a 55kW screw air compressor operating at an ambient temperature of 24°C and a relative humidity of 75% will produce 280 liters of water per day. The accessories we can use for water separation include: aftercoolers, condensate separators, refrigerated dryers, and adsorption dryers. Compress the air to 1/8 of its volume using a compressor with a high pressure of 7 bar (e) ； This also reduces the air moisture content by 7/8. The amount of water that is released as a result of such compression cannot be ignored. For example, a 90kW compressor that draws in air at 20 degrees Celsius and 60% relative humidity will release approximately 85 liters of water during an 8-hour shift. Therefore, it depends on the application environment of compressed air, which in turn determines what combination of coolers and dryers we should choose.