Patent ID: 7879969

Claim:
A method of crystallizing PET pellets in a crystallizer having an inlet, an outlet, and a contact region between the inlet and the outlet, the method comprising: a) introducing a plurality of PET pellets having a PET melting temperature, wherein the plurality of PET pellets have an initial average temperature between 135° C. and 200° C., into the crystallizer; b) spraying a liquid into the contact region of the crystallizer, the liquid having a liquid temperature sufficient to allow at least partial crystallization while maintaining the plurality of PET pellets at an average pellet temperature below the PET melting temperature while in the crystallizer; c) separating the liquid and the plurality of PET pellets by draining the liquid through a drain located within the contact region; and d) removing the plurality of PET pellets having a degree of crystallinity between 30 weight percent and 60 weight percent from the outlet of the crystallizer.