Infrared system for drying PET resin combines drying and crystallizing in one continuous operation, helping manufacturers of bottles, film and sheet reduce the cost and complexity of preparing virgin resin and regrind for production. Consisting of a large, horizontal, stainless steel rotating cylinder and heater bank, the dryer has a helical flight structure on the inside walls of the drum that transports and tumbles the PET pellets through the length. The tumbling helps ensure all pellets are exposed to radiation from the infrared heater bank around which the drum rotates. The moisture driven from the pellets is carried away by a stream of ambient air. As material moves through the drum, the system controller monitors material temperature and automatically adjusts it to ensure optimal drying.