Polymer solution preheater and method for preheating such solutions

摘要

A polymer devolatilization preheater and a method for using the same to preheat a polymer/solvent solution. The preheater includes an elongated, upright hollow vessel defining a heating chamber having a upper and lower ends, and a longitudinal axis extending between the ends. An inlet for a polymer/solvent solution is located adjacent the upper end of the chamber and a molten polymer outlet is located adjacent the lower end of the chamber. A plurality of heating tube bundles are mounted in the chamber, each bundle including a plurality of elongated serpentine heating tubes which are each arranged in a configuration having a major axis which extends across the chamber in a direction transverse to the longitudinal axis of the vessel. The tubes are positioned such that the polymer/solvent solution comes into heat transferring contact with an outer surface thereof as the polymer/solvent solution flows along a path that extends from the polymer/solvent solution inlet to the polymer outlet. Each tube includes a plurality of curved tube portions and a plurality of linking tube portions which interconnect the curved tube portions. The tube portions of each tube are all arranged in common plane that is arranged in essential parallelism relative to the longitudinal axis of the vessel and the tube configuration is essentially rectangular so as to present a pair of opposite edges disposed in essential parallelism relative to the major axis of the tube configuration. The linking tube portions are elongated and arranged so as to extend transversely relative to said major axis and the linking tube portions of each tube are arranged in essential parallelism relative to one another.