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:
Nov. 12, 2019
Filed:
Dec. 22, 2017
Basell Polyolefine Gmbh, Wesseling, DE;
Gabriele Mei, Ferrara, IT;
Massimo Covezzi, Ferrara, IT;
Gerhardus Meier, Frankfurt am Main, DE;
Antonio Mazzucco, Ferrara, IT;
Pietro Baita, Ferrara, IT;
Ulf Schueller, Weiterstadt, DE;
Lorella Marturano, Ferrara, IT;
Enrico Balestra, Ferrara, IT;
Basell Polyolefine GmbH, Wesseling, DE;
Abstract
A process for starting a multizone circulating reactor containing no polyolefin particles, comprising the steps of conveying gas through the reactor and the gas recycle line, feeding a particulate material comprising a polymerization catalyst and optionally polyolefin into the reactor, controlling the gas flow in a vertical reactor zone equipped with a throttling valve at the bottom so that the upwards gas velocity in the bottom part of this reaction zone is lower than the terminal free-fall velocity of the particulate material fed into the reactor, and, after the weight of the particulate polyolefin in this reactor zone is higher than the drag force of the upward moving gas, controlling the circulation rate of the polymer particles within the multizone circulating reactor by adjusting the opening of the throttling valve and adjusting the flow rate of a dosing gas.