METHOD OF RECOVERING LOW-BOILING SUBSTANCES FROM A POLYMER LATEX

摘要

PURPOSE: A method and an apparatus are provided for highly efficiently recovering low-boiling substances such as unreacted chlorovinyl monomers without use of an antifoaming agent. CONSTITUTION: In the method, a polymer latex containing low-boiling substances is sprayed from a nozzle (46, 146) at an upper part of a vaporization drum and vaporizing the low-boiling substances. The polymer latex is sprayed in a first vaporization drum (36) under a pressure of 50-130 Torr onto the whole liquid surface of the polymer latex stored in the vaporization drum, and then the polymer latex is sprayed in a second vaporization drum (136) under a pressure of 100-240 Torr higher than that of the first vaporization drum. At this time the polymer latex is heated at temperatures higher by 10-30°C than the saturated water vapor temperatures in the vaporization drums. Preferably the introduction rate of the polymer latex toward a nozzle is greater than 0.5 m/sec.