In some compressed air treatment applications the operator faces electrical restrictions.  Either power is unavailable, inconvenient to supply, or the installation area may contains explosive gases that make electrical equipment exceedingly expensive to protect.  In these cases, there are a few options for drying compressed air.

1. Membrane dryers have no moving part or power requirement but are limited to small flow rates.
2. Deliquescent dryers have no moving parts or power requirement either.  These are a acceptable choice is a 20 to 63F dew point suppression is acceptable.
3. For high purity requirements (-40 dew point) regenerative desiccant dryers are available with either:
   • NEMA 7 (explosion proof) electrical control enclosures or;
   • Fully pneumatic (air operated) controls

Each of these choices has advantages and disadvantages.  You must weight cost, reliability, and performance.

Parker's PNEUDRI Series is available with a pneumatic controller (see the image below).  I also offer regenerative desiccant dryers with explosion proof electrical enclosures.  Send me an email to learn more.  tyler@moistureboss.com