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:
May. 27, 1997
Filed:
Feb. 12, 1996
Jean-Claude Chinh, Martigues, FR;
BP Chemicals Limited, London, GB;
Abstract
The present invention relates to a process for continuous gas-phase polymerization of olefin(s) in a fluidized and/or mechanically stirred bed reactor, comprising a stage of drawing off the polymer out of the reactor, wherein a portion of the bed is transferred into a lock hopper and is then isolated from the reactor in the lock hopper for a period of 5 to 120 seconds so that a substantial amount of the olefin(s) in the said portion polymerizes, before the polymer thus isolated in the said portion is discharged out of the lock hopper. The process advantageously reduces the amount of the gas drawn off with the polymer to be recycled into the reactor and improves the degassing of the polymer by the heat of the polymerization reaction during the isolation period in the lock hopper (FIG. 1).