A PROCESS FOR SEPARATING AND DRYING THERMOPLASTIC PARTICLES UNDER HIGH PRESSURE

摘要

A process for feeding a slurry of thermoplastic synthetic polymer particles such as polyethylene terephthalate homopolymers and copolymers in combination with a liquid such as water at a liquid temperature greater than the normal boiling point of the liquid, under a pressure greater than the vapor pressure of the liquid at the liquid temperature, into a separation zone such as a centrifugal dryer, and within the separation zone: a. separating the liquid from the particles, and b. drying the particles; while under a high pressure equal to or greater than the vapor pressure of the liquid. There is also provided a process for decoupling the dried particles from the separation zone to an atmosphere having a pressure less than the vapor pressure of the liquid while maintaining the vapor pressure of the particles prior to decoupling equal to or above the vapor pressure of the liquid at the liquid temperature.