Walker Filtration, based in Washington, Tyne & Wear, U.K. and with U.S. headquarters in Erie, Pa., has expanded its line of Pro Dry compressed-air desiccant dryers. Based on customer feedback and the latest controls technology, the new desiccant dryers cut service time in half, significantly increase energy efficiency, reduce noise and are easily customized to meet user requirements, according to the company.
Pro Dry, based on twin-tower heatless desiccant technology, is designed to provide a smooth, controlled and uninterrupted delivery of extremely dry compressed air. In operation, air that needs treatment passes through a prefilter where an electronic drain removes particulates and coalesced liquids from the air stream. Wet air then travels to a valve assembly at the bottom of the unit. Air enters the desiccant bed in one tower, where moisture in the stream adsorbs to the desiccant. Dry air exits the desiccant cartridge through an outlet valve assembly and passes through the unit’s integral 1-micron dust filter, removing any desiccant particulates from air stream.
While one chamber is on-stream removing water vapor, the other is depressurized to permit regeneration. A small amount of dry, process air from the first tower, called purge air, is expanded and routed to the second tower, where it pulls water molecules from the saturated desiccant. Moisture-laden purge air vents to atmosphere through an exhaust valve and silencer. The second tower is repressurized after the desiccant is dry, with the controller ensuring each chamber is at full operating pressure prior to changeover. The air stream is switched and the process repeats on a continuous basis. Thus, the dryer control system cycles air between the two desiccant towers, ensuring reliable and efficient operation.
Engineers have developed a product that provides excellent performance while meeting customer requirements, according to company officials. The benefits of the Pro Dry desiccant dryers include:
- Clean and dry air. With a 0.01-micron oil-removal filter (supplied as standard), 1-micron dust filter, and a choice of –40° or –70° C (–40° or –100° F) pressure dew points, Pro Dry meets or exceeds the highest purity standards as specified in ISO 8573-1.
- Economical. Standard features, such as an integral electronic drain and service-interval indicator, make the unit economical to run. The new models come with an option to upgrade to advanced dew-point management for greater operating efficiency and significantly lower operating costs.
- Energy management. Energy-saving features let the dryer link to a compressor control system to reduce air consumption during periods of low demand.
- Worldwide installation. The units operate on voltages from 100 to 240 Vac and 12 to 24 Vdc, and comply with virtually all appropriate regulatory approvals.
- Rugged construction. Extruded aluminum towers are fully painted for corrosion protection. The built-in CPU is housed in an IP65-rated enclosure.
- Condensate management. Keeping close control over condensate is essential to maximize dryer efficiency. Pro Dry has an electronic drain valve that’s controlled by the CPU. The drain valve opens at the end of every cycle and the CPU runs a diagnostic check for any sign of malfunction. A control panel on the front of the unit permits easy viewing.
- Simple servicing. A removable front panel permits easy access for servicing. A new desiccant cartridge design with integral handle facilitates simple change-out.
The complete Pro Dry line of desiccant dryers covers flow rates from 1.9 to 172 l/sec (4 to 365 scfm). Working pressure is 4 to 16 bar (58 to 232 psig) and inlet air temperature can range from 1.5 to 50° C (34 to 122° F). Minimum ambient temperature is 5° C (41° F). The units are suited for general industrial use, as well as in automotive, paint spraying, instrumentation, packaging, pharmaceutical manufacturing and many other applications.
“The new generation of Pro Dry represents the culmination of development and innovation by our dedicated team,” remarked Group Managing Director, Lianne Walker. “We are excited to bring a superior desiccant dryer to the market, and confident that the exceptional performance and improved design will not only meet our customers’ requirements, but also exceed their expectations.”