Patent ID: 7316079

Claim:
A resin pellet drying method comprising: preheating resin pellets in preheating means to heat the resin pellets to a desired temperature at which the resin pellets are not molten; introducing the preheated resin pellets from the preheating means into reduced pressure drying means; forming a reduced pressure state in the reduced pressure drying means after the preheated resin pellets from the preheating means have been introduced into the reduced pressure drying means by exhausting air inside the reduced pressure drying means while blocking both a supply port and a delivery port of the reduced pressure drying means; rotating a screw in the reduced pressure drying means, while the reduced pressure state is formed, to move the preheated resin pellets through the reduced pressure drying means to the delivery port; heating the resin pellets to a temperature at which the resin pellets are not molten during their movement through the reduced pressure drying means, while the reduced pressure state is formed, to thereby subject the resin pellets to dehumidifying and drying; and discharging the dehumidified and dried resin pellets from the reduced pressure drying means by opening the delivery port of the reduced pressure drying means once the resin pellets in the reduced pressure drying means have been moved to the delivery port.