Patent ID: 7943727

Claim:
Process for heating a polymer-containing stream being transferred from a polymerization reactor to a degassing vessel operating at a pressure between 6 bara and 12 bara, comprising passing the stream through a heater comprising a transfer line for the stream and means for heating the transfer line, wherein the ratio of the stream velocity at the outlet of the heater to that at the inlet, V o /V i , is at least 1.1, typically between 1.2 and 4, the total specific heat transfer area of the transfer line is at least 0.5 m 2 per tonne/h of production of polymer, and the pressure drop across the length of the heater is less than 0.5 bar per tonne/h of polymer, such that at least 90 mol % of the hydrocarbon fluids withdrawn from the polymerization reactor operation are vaporized before entry into the degassing vessel.