All atmospheres contain water vapor, but when air is compressed, the relative humidity of water increases to 100%. To avoid problems caused by water precipitation in piping and connected downstream equipment, a compressed air dryer is essential. In the post-processing equipment of the air compressor, there are mainly air storage tanks, dryers and filters. Dry compressed air can ensure the unobstructed operation of the air compressor air system and the production process. The function of the dryer is to eliminate the condensed water in the compressed air and ensure the discharge of dry and clean compressed air.

overcompression

The air is compressed to a higher pressure than the intended operating pressure, which means more water is condensed out of the system during the compression process. When the air is cooled in the compressor aftercooler, the extra water is separated out. The air is then expanded to working pressure and a lower pressure dew point is obtained. This method is only suitable for very small air flow rates due to its high energy consumption.

Adsorption drying

The working principle of adsorption dryers is simple - moist air flows through a desiccant to dry. Once the desiccant material is absorbed by water, it regenerates to regain its drying ability. Adsorption dryers are typically constructed with two drying vessels, the first drying the incoming compressed air while the second is responsible for regeneration.

Refrigeration desiccant

The refrigerant drying process involves cooling compressed air to allow bulk water to condense and separate. After cooling and condensation, the compressed air is reheated to room temperature so that condensation does not form on the outside of the ductwork.

The dew point is the temperature at which the unsaturated air reduces the temperature while keeping the water vapor partial pressure constant (that is, keeping the absolute water content constant). When the temperature drops to the dew point, condensed water droplets are deposited in the moist air. The dew point of humid air is not only related to the temperature, but also to the moisture content in the humid air. When moist air is compressed, the water vapor density increases and the temperature also rises. When the compressed air is cooled, the relative humidity increases. When the temperature continues to drop to 100% relative humidity, water droplets are precipitated from the compressed air. The temperature at this time is the pressure dew point of the compressed air.

FROM:jiayutezhongzhuangbei