Hankison HSHD Desiccant Air Dryers

HSHD-7 · HSHD-13 · HSHD-18 · HSHD-21 · HSHD-27 · HSHD-40

 

Dry and reliable compressed air – compact desiccant drying technology

Hankison HSHD series is a compact, heatless desiccant air dryer designed for applications where a conventional refrigerated air dryer cannot provide a sufficiently low dew point.

The HSHD series uses two desiccant chambers that automatically alternate between drying and regeneration. This provides a continuous supply of dry compressed air without electrical heating elements and without the need for a large dryer cabinet.

The series covers nominal air flows from approximately 12 to 68 m³/h at a -40 °C dew point, making it suitable for small and medium-sized compressed air installations.

Advantages of the HSHD series

Very low dew point

HSHD can provide compressed air with a dew point as low as -70 °C, depending on the model and operating conditions. The series is therefore suitable for installations where moisture levels need to be significantly lower than those achievable with a conventional refrigerated air dryer.

Compact design

The vertical desiccant modules provide high drying capacity while requiring very little floor space. This makes the HSHD series suitable for point-of-use installations, laboratories and other applications where space is limited.

Heatless desiccant drying

Regeneration is carried out using a portion of the dried compressed air. No electrical heating elements are therefore required for the regeneration process.

Low maintenance requirements

The desiccant is supplied in replaceable cartridges/modules, and the design is intended to make servicing straightforward.

Low noise level

The HSHD series features internal sound attenuation, making it suitable for installation close to work areas.

Flexible installation

The connections and inlet/outlet configuration can be adapted to the installation, making it easier to integrate the dryer into existing compressed air systems.

Model overview

Model Capacity at approx. -40 °C Capacity at approx. -70 °C Dimensions H × W × D Connection
HSHD-7 12 m³/h 8 m³/h 494 × 346 × 168.5 mm 1/2”
HSHD-13 22 m³/h 15 m³/h 666 × 346 × 168.5 mm 1/2”
HSHD-18 31 m³/h 20 m³/h 884 × 346 × 168.5 mm 1/2”
HSHD-21 36 m³/h 23.5 m³/h 1101 × 346 × 168.5 mm 1/2”
HSHD-27 46 m³/h 30.5 m³/h 994 × 386 × 188.5 mm 3/4”
HSHD-40 68 m³/h 45.5 m³/h 1244 × 386 × 188.5 mm 3/4”

The capacities are indicative nominal values and must be corrected according to the actual inlet pressure, temperature and required dew point. Published HSHD data specifies the series at approximately 12–68 m³/h at -40 °C, with lower capacity at -70 °C.

Which HSHD model should you choose?

The Hankison HSHD series is available in six models with different capacities and connections. The right model depends primarily on your compressed air consumption and the required dew point.

See the individual Hankison HSHD desiccant air dryers below to find the model that best matches your compressed air installation.

HSHD-7

The smallest model in the series.

Typical applications:

  • Small laboratories
  • Instrument air
  • Pneumatic instruments
  • Smaller point-of-use installations
  • Applications with relatively low compressed air consumption

Capacity:

  • Up to approx. 12 m³/h at -40 °C
  • Up to approx. 8 m³/h at -70 °C

HSHD-7 is a good choice when very dry compressed air is required but overall air consumption is limited.

HSHD-13

A suitable option for smaller installations with higher compressed air consumption.

Capacity:

  • 22 m³/h at -40 °C
  • 15 m³/h at -70 °C

HSHD-18

Suitable for medium-sized point-of-use compressed air installations.

Capacity:

  • 31 m³/h at -40 °C
  • 20 m³/h at -70 °C

HSHD-21

A larger module that still offers relatively compact dimensions.

Capacity:

  • 36 m³/h at -40 °C
  • 23.5 m³/h at -70 °C

HSHD-27

The 3/4” connection makes this model suitable for higher compressed air flows.

Capacity:

  • 46 m³/h at -40 °C
  • 30.5 m³/h at -70 °C

HSHD-40

The largest model in the HSHD series.

Capacity:

  • 68 m³/h at -40 °C
  • 45.5 m³/h at -70 °C

HSHD-40 is suitable when higher compressed air flow is required while maintaining a compact desiccant dryer design.

How an HSHD desiccant air dryer works

The HSHD series uses two desiccant chambers.

1. Drying

Wet compressed air is directed through one of the desiccant chambers. The desiccant adsorbs water vapour from the air.

2. Dry compressed air output

The dried compressed air leaves the dryer and continues into the compressed air installation.

3. Regeneration

At the same time, the other desiccant chamber is regenerated. A small portion of the dried compressed air is used as purge/regeneration air.

4. Automatic changeover

After the defined cycle, the valves change over so that the previously regenerated chamber takes over the drying process.

The process is repeated continuously, ensuring a constant supply of dry compressed air.

Dew point – choose the right performance

The dew point is an important factor when sizing a desiccant air dryer.

-40 °C dew point

This is typically the best balance between compressed air quality and drying capacity.

Recommended for applications such as:

  • Instrument air
  • Pneumatic systems in moisture-sensitive environments
  • Production equipment
  • General process air
  • Applications where condensation and ice formation must be avoided

-70 °C dew point

Used for applications with very strict requirements for residual moisture.

May be relevant for:

  • Sensitive laboratory processes
  • Pharmaceutical production
  • Critical instrumentation
  • Highly moisture-sensitive processes
  • Applications with particularly strict compressed air dryness requirements

The lower dew point reduces the available air capacity, so the dryer must be sized according to the actual required performance.

Sizing

When selecting a model, you should not look only at the compressor’s nominal capacity.

The following information should be taken into account:

  1. Actual compressed air consumption in m³/h
  2. Operating pressure
  3. Inlet temperature
  4. Required pressure dew point
  5. Ambient temperature
  6. Compressed air quality upstream of the dryer
  7. Any requirements regarding oil and particle content

Hankison’s technical data specifies correction factors because drying capacity changes with inlet pressure. At lower inlet pressures, the maximum air flow is reduced, while higher pressure can increase capacity.

Important: Do not size the dryer right up to its nominal maximum capacity. An appropriate safety margin should be allowed so that the required dew point can be maintained during normal load variations.

Are you unsure which model to choose? Contact us and we will help you size the HSHD dryer.

Filtration before and after the dryer

To ensure reliable operation and a long service life, the HSHD dryer should be installed with suitable pre-filtration.

A pre-filter protects the desiccant from:

  • Liquid water
  • Oil
  • Condensate
  • Particles

A post-filter can be used to retain any desiccant dust and ensure the desired downstream air quality.

Hankison’s manual specifically describes maintenance of both pre- and post-filters as part of the system service programme.

Maintenance

The HSHD series is designed for relatively straightforward servicing, but regular maintenance is important.

Weekly inspection

Check, among other things:

  • That the dryer is operating normally
  • That there are no abnormal leaks
  • That the condensate drain is functioning
  • That no alarm or service indicators are active

Annual maintenance

The official manual includes, among other things:

  • Inspection and servicing of components
  • Replacement of wear parts
  • Inspection of purge solenoid valves
  • Maintenance of pre- and post-filters
  • Inspection of the desiccant
  • Inspection of drains and relevant valves

During servicing, the dryer must always be depressurised and electrically disconnected in accordance with the applicable safety procedures.

Desiccant

The HSHD series uses activated alumina as the desiccant.

The official manual specifies the following desiccant quantities per desiccant chamber/cartridge:

Model Desiccant volume Approx. filling per cartridge
HSHD-7 0.68 4.10
HSHD-13 0.99 6.13
HSHD-18 1.37 8.71
HSHD-21 1.75 11.35
HSHD-27 2.32 14.88
HSHD-40 2.97 19.29

The figures are taken from the HSHD instruction manual’s technical data.

Maintenance kits

Model-specific Hankison HSHD maintenance kits are available.

Model Year 4 kit Part number Year 5 kit Part number
HSHD-7 HSHDMK7-2-4 7458608 HSHDMK7-3-5 7458602
HSHD-13 HSHDMK13-2-4 7458609 HSHDMK13-3-5 7458603
HSHD-18 HSHDMK18-2-4 7458610 HSHDMK18-3-5 7458604
HSHD-21 HSHDMK21-2-4 7458611 HSHDMK21-3-5 7458605
HSHD-27 HSHDMK27-2-4 7458612 HSHDMK27-3-5 7458606
HSHD-40 HSHDMK40-2-4 7458613 HSHDMK40-3-5 7458607

Typical applications

The HSHD series is particularly suitable for installations where space is limited and where very dry compressed air is required.

Laboratories

  • Analytical equipment
  • Instrumentation
  • Test equipment

Hospitals and healthcare

  • Instrument air
  • Sensitive pneumatic equipment
  • Special compressed air applications

Pharmaceutical industry

  • Process air
  • Instrumentation
  • Moisture- and quality-sensitive processes

Industry

  • Pneumatic valves
  • Instrument air
  • Production machinery
  • Process equipment

Quick selection guide

Choose HSHD-7 if the air requirement is up to approx. 12 m³/h at -40 °C.

Choose HSHD-13 if the requirement is around 12–22 m³/h.

Choose HSHD-18 if the requirement is around 22–31 m³/h.

Choose HSHD-21 if the requirement is around 31–36 m³/h.

Choose HSHD-27 if the requirement is around 36–46 m³/h.

Choose HSHD-40 if the requirement is around 46–68 m³/h.

If a -70 °C dew point is required, the capacity must be reduced compared with the -40 °C performance.

Conclusion

Hankison HSHD is a compact solution for producing very dry compressed air where a conventional refrigerated air dryer is not sufficient.

The series consists of six models:

HSHD-7 → HSHD-13 → HSHD-18 → HSHD-21 → HSHD-27 → HSHD-40

with capacities ranging from approximately 12 to 68 m³/h at a -40 °C dew point.

The most important factor when selecting a model is not air flow alone, but the combination of air consumption, operating pressure, inlet temperature and required dew point.

Are you unsure which model to choose? Contact us and we will help you size the HSHD dryer.