Studies on solid desiccant systems for air dehumidification

Abstract

Compressed air is one of the most significant forms of power used in a large amount of manufacturing and non manufacturing sectors due to its many advantages Quality of compressed air is evaluated by its dryness and its concentration of contaminants namely solids water and oil The concentration of contaminants due to compression can be prevented and controlled by using various air treatment accessories such as air inlet filters after cooler and separator The required level of dryness of the compressed air can be achieved by different dehydration technologies such as cooling and condensation and adsorption techniques Adsorption techniques are best suited where extreme low dew point temperature air is needed The air after compression is 100% saturated with moisture and the slightest reduction of temperature causes condensation in the downline of the system Compressed air dryers that use adsorption technique with selected adsorbents or desiccants to altogether remove the water vapour content and produces air at dry and under saturated condition In this condition air cannot condense in the system or the path of the application side In adsorption drying the water vapour present in feed air is attracted to the interior and exterior surface of desiccant and not forming any chemical compound Therefore the desiccants are not to be replaced but only regenerated from time to time The regeneration process can be carried out by partial pressure difference achieved through pressure swing method heatless regeneration or by temperature difference through the temperature swing method Internally heated regeneration newline