Prior to entering the membrane drying module, the
compressed air passes through a high efficiency coalescing
filter to remove oil and water droplets and particulate
contamination with an efficiency of 99.99% at 0.01 micron.
The liquids removed by the filter cartridge continuously
drip from the filter cartridge into the bottom of the
housing, where they are automatically emptied by an
autodrain assembly (see Fig. 1 and Fig. 2). The air leaving
the prefilter, therefore, is laden only with water vapor,
which will be removed in the membrane module.