Patent ID: 8129483

Claim:
A continuous gas phase circulating bed olefin polymerization reactor, comprising: a riser for contacting a catalyst and a first gas composition comprising an olefin to form a polyolefin under fast-fluidization regime or a dilute-phase pneumatic conveying regime conditions; a downer for contacting the catalyst and a second gas composition comprising an olefin to form additional polyolefin under fast fluidization regime or a dilute-phase pneumatic conveying regime conditions; and a transport section for conveying at least a portion of the catalyst, polyolefin, and additional polyolefin from the downer to the riser; a first gas circulation loop for circulating the first gas composition from an outlet of the riser to an inlet of the riser; a device for circulating the first gas composition through the riser and the first circulation loop; a second gas circulation loop for circulating the second gas composition from an outlet of the downer to an inlet of the downer; a device for circulating the second gas composition through the downer and the second circulation loop; and a device for discharging polymer product from the reactor system that comprises a fluidization/settling chamber for segregating the polymer product from the particles circulating through the riser and downer.