FIELD: chemistry.
SUBSTANCE: invention relates to a method for thermal treatment of polyester granules for fractional crystallisation, where molten polyester is fed into an underwater granulation system and granulates. The obtained granulated material is loaded at a short distance from the underwater granulation system into a device for separating the water/solid phase. The dried granulated material is fed into a treatment apparatus without supply or external energy or heat at temperature above 100°C, and thermal treatment for fractional crystallisation takes place due to inherent heat of the granulated material. The treatment apparatus is made in form of reactor which at least inclined, in which the granulated material is fed at temperature above 100°C, passes through it from the loading point to the discharge point under the effect of its own weight and comes out at temperature above 130°C.
EFFECT: disclosed thermal treatment method simplifies the process of fractional crystallisation owing to use of inherent heat of the granules.
7 cl, 2 dwg
