Generally, the filter element is composed of fiber media, filter mesh, sponge and other materials. After the solid and liquid particles (drops) in the compressed air are intercepted by the filter material, they are condensed on the surface (inside and outside) of the filter element. The liquid droplets and impurities accumulated on the surface of the filter element are deposited to the bottom of the filter through the action of gravity and then discharged through an automatic drain or manually.
