Desiccant dryer
Very dry compressed air down to −70 °C pressure dew point
Desiccant dryers use a drying agent that extracts the moisture from the water vapour in the compressed air. This allows them to reach pressure dew points of −40 °C or −70 °C, far below what a refrigeration dryer can achieve.
Two vessels alternate: one dries while the other is regenerated. The regeneration method determines energy consumption. CompAir offers four designs for this.
Pressure dew point
−40 °C, optionally −70 °C
Air quality
ISO 8573-1 class 2 or 1
Designs
4 product lines
How a desiccant dryer works
Moisture always migrates to the driest medium. When compressed air flows through the desiccant, the water vapour passes into it. Once the desiccant is saturated, the dryer switches over and the loaded vessel is regenerated – with dried air, with heat or with the waste heat from the compressor.
Where pipes run outdoors or food, pharmaceutical and electronics applications require very dry air, there is no alternative to a desiccant dryer.
The product lines
AXM – modular · AX – heatless · Heat-regenerated · HC – heat of compression (HOC)
AXM – modular
Compact, for the point of use, up to 300 m³/h
The modular desiccant dryers are very compact and dry the air exactly where it is needed. Inlet and outlet are at the rear, and the smallest models can be wall-mounted.
- Pressure dew point −40 °C, optionally −70 °C
- 4 to 14 bar, up to 300 m³/h
- Pre-filter and after-filter included
- IP54 enclosure, also for outdoor use
- Long cycle time of 10 minutes, only 0.2 bar pressure drop
Model AX1M (-40 °C) to AX50M (-40 °C)
| Model | Capacity | Max. pressure | Pressure dew point | Air inlet/outlet connection | Power supply | Dimensions [mm] | Weight | Desiccant per column | |||
|---|---|---|---|---|---|---|---|---|---|---|---|
| [m³/min] | [m³/h] | [bar g] | [°C] | [BSP (in)] | [V/Ph/Hz] | [W] | [T] | [H] | [kg] | [kg] | |
| AX1M -40°C | 0,08 | 5 | 14 | -40 | 3/8" | 230/1/50-60 | 238 | 212 | 423 | 11 | 0,7 |
| AX3M -40°C | 0,25 | 15 | 14 | -40 | 3/8" | 230/1/50-60 | 238 | 212 | 823 | 18 | 2,2 |
| AX4M -40°C | 0,42 | 25 | 14 | -40 | 3/8" | 230/1/50-60 | 238 | 212 | 1073 | 27 | 3,0 |
| AX7M -40°C | 0,67 | 40 | 14 | -40 | 3/4" | 230/1/50-60 | 475 | 405 | 968 | 44 | 6,4 |
| AX9M -40°C | 0,92 | 55 | 14 | -40 | 3/4" | 230/1/50-60 | 475 | 405 | 1118 | 50 | 8,4 |
| AX12M -40°C | 1,17 | 70 | 14 | -40 | 3/4" | 230/1/50-60 | 475 | 405 | 1318 | 60 | 10,9 |
| AX17M -40°C | 1,67 | 100 | 14 | -40 | 1" | 230/1/50-60 | 475 | 405 | 1673 | 73 | 15,4 |
| AX25M -40°C | 2,50 | 150 | 14 | -40 | 1" | 230/1/50-60 | 475 | 405 | 1873 | 90 | 18,0 |
| AX33M -40°C | 3,33 | 200 | 14 | -40 | 1 1/2" | 230/1/50-60 | 536 | 495 | 1705 | 177 | 30,8 |
| AX42M -40°C | 4,17 | 250 | 14 | -40 | 1 1/2" | 230/1/50-60 | 536 | 495 | 1905 | 180 | 35,9 |
| AX50M -40°C | 5,00 | 300 | 14 | -40 | 1 1/2" | 230/1/50-60 | 536 | 495 | 1905 | 188 | 35,9 |
AX7M -40°C DS to AX50M -40°C DS series
| Model | Capacity | Max. pressure | Pressure dew point | Air inlet/outlet connection | Power supply | Dimensions [mm] | Weight | Desiccant per column | |||
|---|---|---|---|---|---|---|---|---|---|---|---|
| [m³/min] | [m³/h] | [bar g] | [°C] | [BSP (in)] | [V/Ph/Hz] | [W] | [T] | [H] | [kg] | [kg] | |
| AX7M -40°C DS | 0,67 | 40 | 14 | -40 | 3/4" | 230/1/50-60 | 475 | 405 | 968 | 44 | 6,4 |
| AX9M -40°C DS | 0,92 | 55 | 14 | -40 | 3/4" | 230/1/50-60 | 475 | 405 | 1118 | 50 | 8,4 |
| AX12M -40°C DS | 1,17 | 70 | 14 | -40 | 3/4" | 230/1/50-60 | 475 | 405 | 1318 | 60 | 10,9 |
| AX17M -40°C DS | 1,67 | 100 | 14 | -40 | 1" | 230/1/50-60 | 475 | 405 | 1673 | 73 | 15,4 |
| AX25M -40°C DS | 2,50 | 150 | 14 | -40 | 1" | 230/1/50-60 | 475 | 405 | 1873 | 90 | 18,0 |
| AX33M -40°C DS | 3,33 | 200 | 14 | -40 | 1 1/2" | 230/1/50-60 | 536 | 495 | 1705 | 177 | 30,8 |
| AX42M -40°C DS | 4,17 | 250 | 14 | -40 | 1 1/2" | 230/1/50-60 | 536 | 495 | 1905 | 180 | 35,9 |
| AX50M -40°C DS | 5,00 | 300 | 14 | -40 | 1 1/2" | 230/1/50-60 | 536 | 495 | 1905 | 188 | 35,9 |
AX1M -70°C to AX50M -70°C series
| Model | Capacity | Max. pressure | Pressure dew point | Air inlet/outlet connection | Power supply | Dimensions [mm] | Weight | Desiccant per column | |||
|---|---|---|---|---|---|---|---|---|---|---|---|
| [m³/min] | [m³/h] | [bar g] | [°C] | [BSP (in)] | [V/Ph/Hz] | [W] | [T] | [H] | [kg] | [kg] | |
| AX1M -70°C | 0,06 | 4 | 14 | -70 | 3/8” | 230/1/50-60 | 238 | 212 | 423 | 11 | 0,7 |
| AX3M -70°C | 0,20 | 12 | 14 | -70 | 3/8” | 230/1/50-60 | 238 | 212 | 823 | 18 | 2,2 |
| AX4M -70°C | 0,33 | 20 | 14 | -70 | 3/8” | 230/1/50-60 | 238 | 212 | 1073 | 27 | 3,0 |
| AX7M -70°C | 0,53 | 32 | 14 | -70 | 3/4" | 230/1/50-60 | 475 | 405 | 968 | 44 | 6,4 |
| AX9M -70°C | 0,73 | 44 | 14 | -70 | 3/4" | 230/1/50-60 | 475 | 405 | 1118 | 50 | 8,4 |
| AX12M -70°C | 0,93 | 56 | 14 | -70 | 3/4" | 230/1/50-60 | 475 | 405 | 1318 | 60 | 10,9 |
| AX17M -70°C | 1,33 | 80 | 14 | -70 | 1" | 230/1/50-60 | 475 | 405 | 1673 | 73 | 15,4 |
| AX25M -70°C | 2,00 | 120 | 14 | -70 | 1" | 230/1/50-60 | 475 | 405 | 1873 | 90 | 18,0 |
| AX33M -70°C | 2,67 | 160 | 14 | -70 | 1 1/2" | 230/1/50-60 | 536 | 495 | 1705 | 177 | 30,8 |
| AX42M -70°C | 3,33 | 200 | 14 | -70 | 1 1/2" | 230/1/50-60 | 536 | 495 | 1905 | 180 | 35,9 |
| AX50M -70°C | 4,00 | 240 | 14 | -70 | 1 1/2" | 230/1/50-60 | 536 | 495 | 1905 | 188 | 35,9 |
Pre-filter and after-filter are supplied as standard.
Pre-filter: particle removal down to 0.01 micron, including water and oil aerosols; maximum residual oil aerosol content of 0.01 mg/m³ at 21 °C
After-filter: particle removal down to 0.1 micron, including coalesced liquid, water and oil; maximum residual oil aerosol content of 0.03 mg/m³ at 21 °C
AX – heatless
Proven, low purchase cost, twin towers
A small portion of the dried compressed air flows through the second tower and carries the moisture away. The process is simple and reliable. Optional energy management with dew point measurement regenerates only when necessary, reducing purge air consumption.
- Pre-filter and dust filter, IP54 enclosure
- Digital controller, tower pressure gauges, moisture indicator
- Energy management system (EMS) with dew point display as an option
- On request −70 °C, IP65, stainless steel
AX_T series
| Model | Connection size | Capacity | Weight | Dimensions [mm] | |||
|---|---|---|---|---|---|---|---|
| [m³/h] | [m³/min] | [kg] | Length | Width | Height | ||
| AX67TF | 1 ½'' | 400 | 6,7 | 285 | 2160 | 825 | 530 |
| AX83TF | 1 ½'' | 500 | 8,3 | 400 | 2380 | 796 | 550 |
| AX125TF | 2'' | 750 | 12,5 | 520 | 2117 | 970 | 620 |
| AX150TF | 2'' | 900 | 15,0 | 700 | 2305 | 970 | 620 |
| AX167TL | 2'' | 1000 | 16,7 | 828 | 2131 | 1440 | 1035 |
| AX267TL | 3'' | 1600 | 26,7 | 1440 | 2185 | 1928 | 1460 |
| AX333TL | 3'' | 2000 | 33,3 | 1500 | 2185 | 1928 | 1460 |
| AX417TL | DN100 PN16 | 2500 | 41,7 | 1800 | 2041 | 1982 | 1530 |
| AX550TL | DN100 PN16 | 3300 | 55,0 | 2300 | 2349 | 2132 | 1652 |
| AX767TL | DN100 PN16 | 4600 | 76,7 | 2654 | 2349 | 2132 | 1652 |
| AX933TL | DN150 PN16 | 5600 | 93,3 | 2950 | 2535 | 2438 | 1791 |
| AX1133TL | DN150 PN16 | 6800 | 113,3 | 3360 | 2535 | 2438 | 1791 |
| AX1417TL | DN150 PN16 | 8500 | 141,7 | 4400 | 2344 | 2677 | 1945 |
Heat-regenerated
For large air volumes from 9 to 249 m³/min
In heat-regenerated dryers, a blower with a heater warms ambient air and uses it to regenerate the desiccant. Hardly any compressed air is lost, which pays off above all with large flow rates.
- Virtually no purge air loss
- Low-profile design
- For 9 to 249 m³/min
- High reliability in continuous operation
| Model | Connection | Capacity | Weight | Dimensions [mm] | |||
|---|---|---|---|---|---|---|---|
| [m³/h] | [m³/min] | [kg] | Depth | Width | Height | ||
| AHB83TLS | 2" | 500 | 9 | 670 | 995 | 1336 | 1755 |
| AHB150TLS | 2" | 900 | 16 | 958 | 1096 | 1477 | 2186 |
| AHB183TLS | 3" | 1100 | 18 | 1258 | 1398 | 1718 | 2188 |
| AHB233TLS | 3" | 1400 | 25 | 1451 | 1398 | 1718 | 2188 |
| AHB300TLS | 3" | 1800 | 31 | 1710 | 1484 | 2080 | 2016 |
| AHB366TLS | 3" | 2220 | 37 | 1857 | 1484 | 2080 | 2016 |
| AHB433TLS | 3" | 2600 | 45 | 2504 | 1860 | 2622 | 2357 |
| AHB533TLS | DN100 PN16 | 3200 | 53 | 2775 | 1750 | 2622 | 2357 |
| AHB650TLS | DN100 PN16 | 3900 | 65 | 3138 | 1660 | 2622 | 2357 |
| AHB750TLS | DN150 PN16 | 4500 | 75 | 1949 | 3054 | 2541 | |
| AHB883TLS | DN150 PN16 | 5300 | 89 | 4417 | 1949 | 3054 | 2541 |
| AHB1166TLS | DN150 PN16 | 7000 | 119 | 5524 | 2120 | 3407 | 2350 |
| AHB1550TLS | DN150 PN16 | 9300 | 155 | 6072 | 2312 | 3779 | 2462 |
| AHB1766TLS | DN150 PN16 | 10600 | 178 | 7264 | 2355 | 4112 | 2770 |
| AHB2483TLS | DN200 PN16 | 14900 | 249 | 9035 | 2498 | 4464 | 2884 |
* Performance figures refer to air intake at 20 °C, 1 bar and the following operating conditions: 7 bar working pressure, -20 °C pressure dew point, 25 °C ambient temperature, 35 °C compressed air inlet temperature.
HC – heat of compression (HOC)
Regeneration using the waste heat of oil-free compressors
The HC series uses the heat that is generated anyway during compression in an oil-free compressor to regenerate the desiccant. This allows it to reach pressure dew points of −40 °C all year round with almost no additional energy.
- Almost no energy consumption for regeneration
- Negligible purge air loss
- Stable pressure dew points down to −40 °C
- Full-flow valves, low pressure drop
- PLC control, also for multiple compressors
Suitable for the D series, Ultima and DX oil-free compressors. Technical data on request.
Frequently asked questions
Refrigeration dryer or desiccant dryer?
A refrigeration dryer reaches a pressure dew point of +3 °C and is sufficient for most applications; it needs little energy and maintenance. If pipes run outdoors or in cold rooms, or the process requires very dry air, you need a desiccant dryer with −40 °C or −70 °C. In between lies the Sub-Zero dryer with −20 °C.
What is the pressure dew point?
The temperature at which the moisture in the compressed air begins to condense. The lower the pressure dew point, the drier the air. ISO 8573-1 divides air quality into classes accordingly: class 4 corresponds to +3 °C, class 3 to −20 °C, class 2 to −40 °C and class 1 to −70 °C.
Which regeneration method is right?
Heatless dryers are inexpensive to buy but consume purge air. For large air volumes, a heat-regenerated dryer pays off, and downstream of an oil-free compressor the HOC dryer costs almost nothing to run. We do the calculation for your system.
Does the desiccant need to be replaced?
Yes, its effectiveness declines after a few years. How long it lasts depends on the load. During maintenance, we check the dew point, filters, valves and desiccant.
Who maintains the compressor?
We do. As the CompAir partner for north-western Switzerland, we maintain and repair your system with genuine spare parts and service kits. If your compressed air supply fails, you can reach our on-call service on 062 552 00 88.
Downloads
Which dryer is right for your system?
Flow rate, pressure, required pressure dew point and the environment determine the choice. We size the dryer and filters to suit your compressor, install them and take care of service.