Membrane Air Dryers

  • Configured for high volume OEM requirements
  • Offer a reliable, efficient, and economical alternative to pressure swing and refrigerant dryer technologiesDura Dry Membrane Air Dryers
  • Require no electricity thus lowering operating costs
  • Dewpoints as low as -40°F (-40°C) prevent freeze-ups
  • Explosion proof
  • Silent operation
  • No desiccant to change
  • Eliminates condensate discharge typical of refrigerant dryer technology

DuraDRY Membrane Air Dryers combine a superior coalescing technology with a proven, innovative membrane system to supply clean, dry compressed air with dewpoints as low as -40°F (-40°C). The DuraDRY Membrane Dryers are available in 10 different models which can deliver compressed air at flow rates up to 10 SCFM with a -40°F (-40°C) dewpoint; or deliver compressed air at flow rates up to 40 SCFM with a 32°F (0°C) dewpoint. The DuraDRY Membrane Air Dryers are engineered for easy installation, operation, and long term reliability. The Dryers incorporate high efficiency coalescing filtration and the highest efficiency membrane available to provide low cost operation and minimal maintenance.

State-of-the-Art Membrane Technology

Water vapor from the compressed air supply passes through the hollow fibers of the membrane. At the same time, a small portion of the dry air product is redirected along the length of the fibers to sweep out the water vapor laden air which has permeated the membrane. The moisture-laden sweep gas is then vented to the atmosphere, and clean, dry air is supplied to the application. The drying power of the membrane is controlled by varying the compressed air flow rate and pressure. The DuraDRY Membrane Air Dryer is designed to operate continuously, 24 hours per day, 7 days per week. The only maintenance required is changing the prefilter cartridge once a year. This annual maintenance takes approximately 5 minutes.

Phase I – Coalesing Filtration

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 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.

Phase II – Drying

The water vapor in the compressed air is removed by the principle of selective permeation through a membrane (see Fig. 3). The membrane module consists of bundles of hollow membrane fibers (see Fig. 4), each permeable only to water vapor. As the compressed air passes through the center of these fibers, water vapor permeates through the walls of the fiber, and dry air exits from the other end of the fiber. A small portion of the dry air (regeneration flow) is redirected along the length of the membrane fiber to carry away the moisture-laden air which surrounds the membrane fibers. The remainder of the dry air is piped to the application.


  • Low dewpoint instrument air
  • Pneumatic equipment
  • Pressurizing electronic cabinets
  • Analytical instrumentation
  • Prevention of freeze-ups
  • Dry air for hazardous areas
  • General laboratory air supply
  • Air for air bearings
  • Air for electrostatic painting
  • Ozone generators
  • Dental air

There’s much more we can tell you about DuraDRY Membrane Air Dryers and how they can work for you. Learn more by contacting us online, or give us a call. We’re excited to help.