The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 31, 1993
Filed:
Mar. 04, 1991
BP Chemicals Limited, London, GB;
Abstract
The present invention relates to a process and a device for polymerizing alpha-olefins such as ethylene or propylene in a gas phase. The device comprises a gas phase polymerization reactor (5) into which a suspension of prepolymer particles in liquid saturated hydrocarbon(s) is continuously introduced. The prepolymer suspension is prepared in one or more prepolymerization vessels (14) and is continuously passed to a post-treatment unit comprising a degassing means (10) wherein most of the dissolved unreacted olefinic monomer(s) is separated. Preferably, the post-treatment unit may comprise a particle separation means (11) for removing the finest and/or coarsest prepolymer particles from the suspension and/or a concentration means (11a) for concentrating the suspension. High activity catalyst can be used in the process with reduced amounts of prepolymer agglomerates. Prepolymer can be obtained with a constant quality and a desired size.