Hitachi - Inspire the Next
Contact Us

Find A Local Rep

1-800-785-5247 or 1-219-879-5451

Compressed Air Treatment Solutions

Air Treatment Solutions Designed for Reliability and Efficiency

  • Refrigerated Air Dryers 10 to 10,000 cfm
  • Desiccant Air Dryers 3 to 7500+ cfm
  • Filters & Mist Eliminators
  • Drains
  • Oil/Water Separators

The Importance of Clean, Dry Compressed Air

Water jeopardizes everything you want your compressed air system to do. Failure to remove this water ruins product and fouls process. A reliable air treatment system is vital to help protect your equipment and your operations.

Also, a complete air treatment system can help optimize air flow thus helping lower your operating costs.

  • Air Quality Standards
  • Desiccant Dryers
  • Refrigerated Dryers

Air Quality Standards

Clean, Dry Compressed Air Is Critical For All Operations

ISO Air Quality Class filtration schematic

Moisture and contaminants can pose a huge risk to your operation. That’s why an efficient air treatment system is vital to help keep your air stream clean and dry.

How to Determine the Air Purity Needed for Your Operation

ISO standards are globally recognized and used for quality assurance in most industries. For compressed air, ISO 8573-1 classes determine air quality standards. To determine air quality standard for operations, three parameters are used.

  • Solid Particles: Measure of the solid particles contained in the compressed air stream.
  • Pressure Dew Point: Measure of the maximum allowable water content in the compressed air stream.
  • Oil (including vapor): Measure of the maximum allowable oil content in the compressed air stream.

The diagram on the right and chart below can help determine air quality standards and how to achieve the correct air purity level.

ISO Air Quality Class standards chart

Desiccant Dryers

Ideal for Applications Requiring Extremely Low Dewpoint

Sullair Desiccant Compressed Air Dryers are engineered for the most critical applications — providing dry compressed air where you need it most.

  • Flow Range: 3 to 7500 + cfm
  • Dew point range: −4 to −100°F (−20 to −73°C)
  • ISO 8573-1:2010 Air Quality Class Range: Classes 1, 2 and 3

How Desiccant Air Dryers Work

Sullair Desiccant Dryers have a dual tower design in which both vessels are filled with desiccant material. Moisture migrates to the driest material available. Desiccant material adsorbs moisture—separating it from saturated compressed air. (As long as the desiccant material is drier than the air entering the dryer.)

  1. Saturated, compressed air passes through vessel one where the desiccant adsorbs moisture. This helps lower the dewpoint to expel dry compressed air 
  2. Once vessel one reaches a set level of saturation, the air switches to pass through vessel two 
  3. While the air is passing through vessel two, vessel one dries and regenerates the desiccant material
  4. When vessel two reaches a set level of saturation, the air switches to pass through vessel one

Types of Desiccant Dryers

Desiccant dryers are classified by regeneration methods.

Heatless Dryers

Uses an average of 15% of process air during the regeneration process

  • Heatless dryers divert a small amount of dried process air from the drying vessel to regenerate the opposite vessel.

Heated Dryers

Uses an average of 8% of process air during the regeneration process

  • Heated dryers use an additional heat source—reducing process air loss during the regeneration process. The additional heat source helps enhance the drying and regeneration process while saving energy.

Heated Blower Purge Dryers

Uses an average of 2% of process air during the regeneration process

  • Heated Blower Purge dryers use a combination of an additional heat source, air from a blower and little to no process air. The three-tiered method helps optimize drying and regeneration processes while reducing energy consumption — maximizing energy cost savings over the lifecycle.

Benefits of Desiccant Compressed Air Dryers

  • Operation in subzero temperatures
  • Can achieve higher air purity—ISO ISO 8573-1:2010 Air Quality Classes 1, 2 and 3

Refrigerated Dryers

Diagram showing how a refrigerated compressed air dryer works

Sullair Refrigerated Air Dryers reliably remove harmful moisture and contaminants from compressed air, helping protect your compressed air system, machinery and downstream tools.

  • Flow Range: 10 to 10,000 cfm
  • Dew point range: 37 to 50°F (2.8 to 10°C)
  • ISO 8573-1:2010 Air Quality Class Range: Classes 4, 5 and 6

How Refrigerated Dryers Work

  1. Saturated compressed air enters the system and is precooled in the air/air heat exchanger.
  2. Then, precooled air moves downstream through the air/refrigerant heat exchanger. The heat exchanger’s vertical profile design reduces condensed moisture by nearly 99% using gravitational force.
  3. To prevent separated droplets from reentering the airstream, condensate collects in a large reservoir with subsequent recirculation where flow velocity is significantly reduced.
  4. Accumulated condensate is then discharged from the dryer via drain. The dried, cold process air passes back through the heat exchanger to be reheated — reducing relative air humidity and recovering up to 60% cooling capacity.

Types of Refrigerated Dryers


Ideal for running at full load

  • Maintain constant energy consumption no matter flow or air demand
  • Hot gas bypass maintains a stable dew point in varying operating conditions and controls refrigerant amount circulating


Ideal for operations with variable flow rates

  • Solenoid valves close in low demand periods trapping refrigerant in a fully insulated heat exchanger
  • This creates a thermal mass which switches off the dryer when a pre-determined temperature is reached for energy savings

Benefits of Refrigerated Dryers

  • Economical
  • Energy efficient
  • Low maintenance

Featured Air Treatment Products

view all air treatment products
back arrow
Desiccant Dryer Assortment

Desiccant Air Dryers

3 – 7500 cfm
.08 – 212.4 m³/min
58 – 232 psi
4.0 – 16.0 bar
Refrigerated Dryer Collage

Refrigerated Air Dryers

10 - 10,000 cfm
.28 - 283.2 m³/min
200 - 232 psi
13.8 - 16 bar
Filtration Assortment

Air Compressor Filters and Mist Eliminators

25 - 21,000 cfm
.71 - 594.7 m³/min
232 - 725 psi
16 - 50 bar
SULLIPRO Oil/Water Separator

Sullair Oil/Water Separators

45 - 7200 cfm
1.3 - 203.9 m³/min
15 - 350 hp
11 - 261 kW
232 psi
16.0 bar
forward arrow


This site uses essential cookies for core functionality and analytics cookies to collect anonymous usage data. Click “Accept Cookies” to accept all cookies or “Cookie Settings” to choose which types of cookies you wish to accept. View our Privacy Policy.
Accept Cookies Cookie Settings

Use the checkboxes to select the types of cookies you want to accept, then press the “Save Settings” button. View our Privacy Policy.

  • Essential cookies enable core functionality of the site. These cannot be disabled.
  • Analytics cookies collect anonymous usage data to help us understand how visitors interact with the site and improve their experience.
Save Settings