SRD Heatless Desiccant Compressed Air Dryers

Specifically designed to meet the demanding requirements of compressed air systems used in trains, rail transport and rolling stock.

Air Purification Skroll® SRD dryers are specifically designed to meet the demanding requirements of the rail industry. The SRD dryer range provides performance results exceeding those of existing & traditional technologies, efficiently removing contaminants from air and gas to provide unparallel protection of rail compressed air systems. At the heart of every SRD dryer is the patented Skroll® adsorption medium which is proven to outperform other desiccant media with its revolutionary design.

Patented Skroll® Technology

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Performance

Unparalleled Performance Results

This exciting new range of dryers are designed to meet the demanding requirements of the rail transport industry, with performance exceeding all other traditional drying technologies. Designed for durable, heavy duty performance, each dryer is capable of providing high adsorption density, variable dew point suppression, energy saving, shock & vibration resistance, corrosion resistance, and minimal maintenance. Skroll® SRD dryers outperform all other technologies, even in the most demanding and arduous conditions.

The SRD Dryer combined with Skroll® media technology is a winning combination unequalled by existing technologies, and the only choice for outstanding performance in demanding mobile applications.

  • Durable, robust construction for heavy duty performance
  • Designed for the most demanding and arduous conditions
  • High adsorption density
  • Variable dew point suppression
  • Highly efficient - saving energy
  • Shock, vibration & corrosion tested
  • Minimal maintenance
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Operating Principle

This SRD dryer uses the pressure swing adsorption (PSA) principle of drying compressed air, utilising two identical columns fitted with replaceable cartridges. Each cartridge contains advanced Skroll® adsorption medium specifically developed for use in compressed air dryers operating in arduous conditions. Compressed air dryers containing Skroll® adsorption medium have been developed with a particular focus on robust design for application in rail transportation where reliable performance and minimum servicing is required. It operates to provide stable Dew Point Suppression (DPS) throughout its operating range of temperatures and pressures of typically ≥40°C.

In operation, compressed air passes through the SRD adsorption cartridge ‘A’ (see image below) where moisture is adsorbed and the air is subsequently dried. Simultaneously, a small amount of this dry air is depressurised and counter-flowed, via the Non-return Valve (NRV) orifice, down through cartridge ‘B’ (see image below) and exhausted to atmosphere. The result is that cartridge ‘B’ becomes regenerated to a dry state ready for use once again.

The dryer controller periodically switches the control solenoid valves, reversing the function of each column and therefore ensuring the continuous supply of clean and dry air. The cycle time is typically 1 minute per side, 2 minutes per complete cycle.

Control spool valves are of the Normally Open Type to ensure a continuous supply of air in the event of a temporary interruption to the power supply to the dryer controller. Skroll® drying medium will recover fully from this condition once normal operation is resumed and power restored.

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Media

Skroll® Media

At the heart of every SRD dryer is the patented Skroll® adsorption medium technology which is proven to outperform other desiccant media with its unique performance characteristics and revolutionary design.

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