Patent ID: 7655192
Filing Date: 2010-02-02
Classification: B01J,C08F

Abstract:
1. An apparatus for discharging polymer from a continuously operated gas phase reactor having an upper part and a bed, wherein at least one monomer is polymerized in the bed which contains active catalyst formed by catalyst and polymer particles suspended in a fluid, said bed defining a fluidized bed level in said reactor, said apparatus comprising: an outlet nozzle communicating with the fluidized bed of the gas phase reactor, a collecting vessel placed in communication with the outlet nozzle for separating gas from solid material, with a screen for collecting lumps within said collecting vessel and a separate discharge nozzle for the lumps, the discharge nozzle being adjacent to the screen; a gas recycle line for recycling gas from the gas space of said collecting vessel to the upper part of said reactor; a continuously operating valve for controlling the gas flow in said gas recycle line and adjusting the amount of polymer powder withdrawn from the reactor via the outlet nozzle, the valve also adjusting the discharge rate of the polymer powder so as to maintain a constant bed level during polymerization; a continuously operating control valve for regulating the flow of polymer powder from said collecting vessel; and an on-off valve for removal of lumps from said collecting vessel.