Adsorption Dryers

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An Adsorption Air Dryer is designed to remove condensate from compressed air in the most critical applications.

Feature

  • Also known as Desiccant Dryers
  • Used in specialized manufacturing processes that need exceptionally dry air. eg. :Pharmaceuticals, electronics, lab equipment, auto refinishing.
  • Have two parallel towers filled with beads of activated alumina. Compressed air flows upwards :within one tower of the Adsorption or Desiccant Air Dryer while the second tower is regenerated with a small stream of the dried air (over a 5 - 10 minute period). The activated alumina is a hygroscopic, hard, durable desiccant material that should last for approx 5 years if adequately protected from contamination by compressor oil.
  • Can be setup with a constant pressure dew point of -40°C to -70°C dew point.

Types

The adsorption air dryer is normally used to get CO2 free air. There are three kinds of adsorption air dryer. These are:

  • CAS-Series Carbon Dioxide Adsorbers
  • VCD-Series Carbon Dioxide Adsorbers
  • MCA Series Carbon Dioxide Adsorbers

CAS-Series Carbon Dioxide Adsorbers

The Twin Tower Engineering CAS-Series carbon dioxide adsorbers are designed to remove CO2 from compressed air for outlet flows up to 320SLPM (11.3 SCFM). The carbon dioxide adsorber does this by using media beds featuring 13X molecular sieve in a pressure swing adsorption process for a more efficient adsorbtion of CO2. Outlet CO2 levels less than 1 PPM; outlet H2O levels less than -100°F dew point. Adsorbed moisture and CO2 are vented to atmosphere while dry CO2 free air is provided at the outlet port. Design Features includes solid state timer with LED display for visual monitoring for cycle, fixed orifice designed for consistent, trouble free purge flow and continuously self-regenerative operation. Purge mufflers and power cord standard. Standard voltage is 115 VAC. 230 VAC is available. Standard operating pressures are from 50 to 150 psig. Industries utilizing these CO2 Adsorbers are Continuous Emissions Monitoring Systems (CEMS), FTIR Spectrometers, Gas Chromatographs, Laboratory Analyzers, NMR Spectroscopy, TOC Analyzers, Environmental Chambers, and Zero Air Systems.

VCD-Series Carbon Dioxide Adsorbers

The Twin Tower Engineering VCD-Series carbon dioxide adsorbers are designed to remove CO2 from compressed air for outlet flows up to 99 SLPM(3.5 SCFM). The carbon dioxide adsorber does this by using media beds featuring 13X molecular sieve in a pressure swing adsorption process for a more efficient adsorbtion of CO2. Outlet CO2 levels less than 1 PPM; outlet H2O levels less than -100°F dew point. Adsorbed moisture and CO2 are vented to atmosphere while dry CO2 free air is provided at the outlet port. Design Features includes direct acting solenoid valves for positive shifting and reliable flow control, fixed orifice designed for consistent, trouble free purge flow. Components are easily serviced and field replaceable, continuously self-regenerative operation. Ultra-compact size can be mounted in any position, purge mufflers and power cord standard. Standard voltage is 115 VAC. 230 VAC is available. Standard operating pressures are from 50 to 150 psig. Industries utilizing these CO2 Adsorbers are Continuous Emissions Monitoring Systems (CEMS), TOC Analyzers, Environmental Chambers, FTIR Spectrometers, Gas Chromatographs, Laboratory Analyzers, NMR Spectroscopy, and Zero Air Systems.

MCA Series Carbon Dioxide Adsorbers

The Twin Tower Engineering MCA-Series Carbon Dioxide Adsorber/Dryers use the pressure swing adsorption method of CO2 removal and drying compressed air. This requires two identical towers containing beds of 13X molecular sieve beaded media. Incoming compressed air enters the adsorber/dryer through the four-way solenoid valve, where it is directed to the bottom of the tower containing active 13X media (T1). The media in this tower removes CO2 to less than 2 ppm and 99.9+% of the water vapor from the air when operated at catalog conditions. The dry, CO2 free air leaving the top of the tower (T1) is directed to the outlet through a shuttle valve. The purge orifice allows a portion of the dry, CO2 free air to flow into the other tower (T2) being regenerated. This cleaned purge air regenerates the desiccant by removing the accumulated CO2 and water vapor and carrying it out the open purge port. The 4-way solenoid valve is controlled by a solid state timer. After 30 seconds, the desiccant in tower T2 is regenerated, and the timer de-energizes the solenoid valve causing the process to instantly reverse, with tower T2 adsorbing and tower T1 regenerating.