Patent ID: 7807761

Claim:
Equipment for the gas-phase polymerization of olefin(s), comprising: a reactor with a fluidized or mechanically stirred bed and with a vertical side wall, provided at its base with a fluidization grid, the vertical side wall of the reactor extending a height H above the fluidization grid, a conduit for external circulation of a reaction gas mixture, connecting the top of the reactor to the base of the reactor under the fluidization grid and including a compressor and at least one piece of equipment for heat removal, a bed level controller, at least one withdrawal conduit for withdrawing polymer, at least one uplift conduit, at least one recovery gas lock hopper equipped with a discharge valve, and at least one degassing chamber, wherein (i) the at least one withdrawal conduit connects the reactor to the at least one recovery gas lock hopper, the at least one withdrawal conduit has an isolation valve prior to the recovery gas lock hopper and the at least one withdrawal conduit leaves the side wall of the reactor at a height of the reactor wall above the fluidization grid ranging from 0 H to 0.15 H, whilst being directed in a downwards fashion at an angle A with the horizontal plane ranging from 20 to 75 degrees below the horizontal plane, and said withdrawal conduit having an internal diameter of between 5.0 and 20.5 cm, (ii) the recovery gas lock hopper has a volume of at least 200 liters, (iii) the at least one uplift conduit is connected between the recovery gas lock hopper and an inlet of the degassing chamber and has a vertical height of at least 20 m and an internal diameter of between 5.0 and 20.5 cm, and provides transport in an upwards direction in the direction of flow between the reactor and the inlet of the degassing chamber, (iv) the inlet of the at least one degassing chamber is disposed at a vertical height above the vertical height at which the withdrawal conduit leaves the side wall of the reactor, and (v) at least one means is provided for flushing the at least one uplift conduit.