New PCT3 Series desiccant dryer from Universal Dynamics, Inc., Woodbridge, Va., is designed to minimize energy use at every stage of the drying process. It is aimed at high-temperature drying, such as PET, and for low-temperature PLA biopolymers. Air flow is optimized with variable-speed blowers and temperature sensing. A water-saver valve minimizes water use to cool air on the return side. And regeneration exhaust air is recycled to a heat exchanger to preheat air for the regeneration heater. For future development, the dryer will also adjust to ambient humidity.
This compact, highly stable system provides ultra-low dewpoints down to -100 F, which extend cycles between bed changeover, reducing wear and tear. Instead of the usual desiccant regeneration four times in 24 hr, the PCT3 regenerates once a day. Throughputs are 100 to 6000 lb/hr with a temperature range of 120 to 375 F. It comes in gas, electric, or dual-fuel versions.