Patent ID: 8372923
Filing Date: 2013-02-12
Classification: B01J,C08F,F16L,Y10T

Abstract:
1. A process for improving the devolatilization of polymer slurry produced in a polymerization loop reactor comprising: introducing ethylene monomer, one or more optional olefin co-monomers and a diluent into a loop polymerization reactor; introducing at least one polymerization catalyst into the reactor; polymerizing the ethylene monomer and the optional co-monomer to produce a polymer slurry comprising liquid diluent and solid ethylene polymer particles; periodically withdrawing the polymer slurry from the polymerization reactor; and passing withdrawn polymer slurry through a heated flash line into a flash tank, wherein a temperature of an interior surface of the flash line is adjusted to a temperature which is equal to or higher than a softening temperature of the polymer particles passing therethrough and wherein the temperature of the interior surface is higher in a first half of the length of the flash line than in a remaining length of the flash line, wherein the flash line comprises a pipe that is provided with a jacket, and wherein the process comprises flowing polymer slurry through the pipe and flowing a heating fluid for heating the flash line through the jacket, whereby the heating fluid flows in a direction which is countercurrent to the polymer slurry, wherein the loop polymerization reactor comprises a second loop reactor of a double loop reactor system.