In most desiccant drying systems desiccant regeneration is done with heaters and blowers that are run on a timed cycle. This cycle allows the dryer to operate at the right temperature to dry the material completely.

A new large-capacity, multiple- bed dryer is designed differently. Instead of setting a cycle based on time, the user sets the temperature desired for regeneration. This way, the temperature is monitored to signal when the regeneration cycle is complete, thus eliminating the possibility of regenerating more or less than required, and saving energy. According to the manufacturer, it can reduce energy consumption by as much as 50 percent compared to conventional two-bed and rotary-bed dryers. The unit also adjusts to outside conditions like humidity. The HP4-X dryer, available in 400- and 500-lb/hr capacities, achieves regeneration with dry process air using a single blower with a stationary tower design.

Featuring closed loop regeneration control above 300 lb/hr, the system is designed to prevent temperature spikes on bed shift. The dryer uses 45A, so natural gas conversion packs are not needed, says the manufacturer. With no moving parts, seal and maintenance problems are eliminated. The new units join the smaller 300-lb/hr dryer already on the market. They start at about $15,000 and include the controller.

Dri-Air Industries
East Windsor, CT
Phone: (860) 627-5110
Fax: (860) 623-4477
www.dri-air.com