The importance of removing water from compressed air cannot be ignored

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It is essential to remove oil and water from compressed air. Why is it necessary to remove water from compressed gas? Removing moisture from compressed air is the primary task in its purification. Water contained in compressed air, along with various impurities, can erode pipes, valves, instruments, and equipment, leading to increased production costs. Moreover, in the pharmaceutical industry, if the gas contains moisture, it can affect the quality of drugs and pose a threat to the safety of those who take them. The moisture in compressed air comes from the atmosphere. The atmosphere generally contains a certain amount of water in gaseous form. Water vapor in the air begins to condense into water droplets and precipitate only when there is an excess of water vapor, exceeding its saturation level (that is, when the relative humidity is >100%), or when the air cools below its dew point temperature. The absolute amount of moisture in the air can be expressed by the wet content x, measured in kg (water vapor) per kg (dry air), that is, the number of kilograms of water contained in each kilogram of dry air. The relative humidity of air is expressed as a percentage, and it is the ratio of the amount of water vapor present in the air to the maximum amount of water vapor that the air can hold at that temperature (i.e., the saturated amount), or it is the ratio of the partial pressure of water vapor in the air to the saturated vapor pressure of water at the same temperature. The dew point of air is the temperature at which air containing a certain amount of water vapor is cooled to a relative humidity of 100%, at which point water droplets begin to form. The saturated vapor pressure and moisture content of pure water vapor are shown in the table. https://pic.ouryao.com/data/attachment/forum/202011/13/113222lzpsx6t6556sm0p0.jpg.thumb.jpg What are the methods for compression and water removal? It can be seen that the most direct way to remove moisture from compressed air is to cool it; after cooling, the dew point is reduced, and a large amount of excess water vapor will then precipitate out. Equipment such as compressed air dehumidification filters, heat-free regeneration dryers, and freeze-dryers can be used to remove water vapor from compressed air through methods like pressurization, cooling, and adsorption, while liquid water is removed through methods such as heating, filtration, and mechanical separation. The compressed air water separator utilizes the principle of combining centrifugation and collection, as well as an optimal integration of mechanisms such as gravity and collision, to effectively remove liquid water mist from compressed air. It is a necessary pre-treatment device for high-efficiency compressed air filters as well as refrigerated and adsorption-type compressed air dryers ； The heat-free regeneration dry dryer operates on the principle of pressure swing adsorption: when one drying tower is in use, the moisture in the air is absorbed by the desiccant. After drying, most of the air is available for use by the user, while a small portion of this air goes to the other drying tower to regenerate the desiccant. Through appropriate automatic control, the two towers are used alternately to achieve the purpose of drying air ； A freeze dryer is a device that cools compressed air in order to remove the water vapor contained within it, thereby producing relatively dry compressed air. Nevertheless, after being cooled, the compressed air still has a relative humidity of 100%. Although there are water removal devices, they are not capable of removing all the water droplets. Sending this compressed air directly into filters and similar devices can easily cause the filtering media to become damp, reducing the filtering efficiency and leading to filtering failure. For this reason, it is necessary to reheat the compressed air from which water has already been removed. The reheated compressed air can reach a relative humidity of around 60% under operating conditions, at which point the subsequent filtering media are safe and reliable. Therefore, water removal from compressed air must be given attention? In summary, a water removal filter is essential, while the choice between a freeze-dryer and an adsorption dryer should be based on the operating conditions. Although most pharmaceutical companies currently equip themselves with such devices, when choosing an adsorption dryer, factors such as energy consumption, water removal efficiency, and purchase cost need to be taken into consideration. https://pic.ouryao.com/data/attachment/forum/202011/13/114732gcyoyxvyvzy7bnmn.jpg.thumb.jpg The economic performance analysis above is for reference only