PRODUCTION OF POLYOLEFIN

PURPOSE:To facilitate the control of the olefin composition, by heating a portion of vaporized olefins separated from a slurry of a solid polyolefin in liquid olefins and utilizing the heated vaporized olefins as a heat source for a flash tank. CONSTITUTION:A polymerization tank 1 is fed with an olefin 4 and catalytic components 2 and 3. A polyolefin slurry obtained by polymerization under conditions in which the olefin remains liquid is passed through a thickener 9 to a flash tank 10, where the liquid olefins are vaporized by heating, leaving the solid polyolefin, which is discharged through a pipe 15. The vaporized olefins are fed to a wet type scrubber 14 where the olefin vapor is scrubbed by contacting it with a liquid olefin introduced from a pipe 16. The scrubbed liquid olefin is circulated by a pump 18 to the polymerization tank 1, and a portion of the scrubbed olefin vapor is heated in a heat exchanger 12 and passed to the flash tank 10. The remaining portion of the vapor is liquefied by a condenser 20, a portion of the liquid is circulated to an apparatus 14, and the remaining portion is circulated to the polymerization tank 1.