Abstract: Various methods and systems for removing particulates from a cycle gas stream, e.g., in a reactor system, are provided. In certain embodiments, the methods are performed in conjunction with a polymerization reactor system such as a gas-phase reactor system.

Abstract: A polymer finishing process including: recovering polymer powder from a polymerization reactor; feeding the polymer powder to an inlet of a mass flow screw conveyor and one or more mass measuring devices for determining a mass of polymer powder within at least a portion of the mass flow screw conveyor; measuring at least one of a mass of the polymer powder in the screw conveyor and a combined mass of the screw conveyor and the polymer powder within the screw conveyor with the one or more mass measuring devices; and determining a mass flowrate of polymer powder through the mass flow screw conveyor based on the at least one of the measured mass of the polymer powder in the mass flow screw conveyor and the measured combined mass. A method of controlling a polymerization process using a mass flow screw conveyor is also disclosed.

Abstract: A system in one embodiment includes a barrier; an inverted cone in the barrier; and a member under the inverted cone and having dimensions that cause solids passing therealong between the member and the barrier to have about a constant velocity profile thereacross. A method for purging a gas from a solid/gas mixture according to one embodiment includes adding solids to a barrier having an inverted cone therein and a member under the inverted cone, wherein the solids passing along the member have about a constant vertical velocity profile thereacross; and injecting a purge gas into the solids from at least one point adjacent the member.

Abstract: A system in one embodiment includes a barrier; an inverted cone in the barrier; and a member under the inverted cone and having dimensions that cause solids passing therealong between the member and the barrier to have about a constant velocity profile thereacross. A method for purging a gas from a solid/gas mixture according to one embodiment includes adding solids to a barrier having an inverted cone therein and a member under the inverted cone, wherein the solids passing along the member have about a constant vertical velocity profile thereacross; and injecting a purge gas into the solids from at least one point adjacent the member.

Abstract: A polymer finishing process including: recovering polymer powder from a polymerization reactor; feeding the polymer powder to an inlet of a mass flow screw conveyor and one or more mass measuring devices for determining a mass of polymer powder within at least a portion of the mass flow screw conveyor; measuring at least one of a mass of the polymer powder in the screw conveyor and a combined mass of the screw conveyor and the polymer powder within the screw conveyor with the one or more mass measuring devices; and determining a mass flowrate of polymer powder through the mass flow screw conveyor based on the at least one of the measured mass of the polymer powder in the mass flow screw conveyor and the measured combined mass. A method of controlling a polymerization process using a mass flow screw conveyor is also disclosed.

Abstract: A rotary feeder for feeding a particulate material including: a cylindrical housing comprising a feeder inlet, a first feeder outlet, and a second feeder outlet; a rotor mounted in the cylindrical housing including a plurality of substantially impeller blades defining a plurality of circumferentially spaced pockets alignable with the feeder inlet, first feeder outlet, and second feeder outlet, and adapted to sweep a wall of the cylindrical housing as the rotor rotates in the cylindrical housing; a device for rotating the rotor; and a separating screen in the first feeder outlet to substantially prevent oversize material from exiting through the first feeder outlet, wherein each of the plurality of circumferentially spaced pockets will align with the feeder inlet to receive therein a particulate material and an oversize material through the feeder inlet, rotate in the cylindrical housing to align with the first feeder outlet and discharge the particulate material therefrom, and rotate in the cylindrical housin

Abstract: Various methods and systems for removing particulates from a cycle gas stream, e.g., in a reactor system, are provided. In certain embodiments, the methods are performed in conjunction with a polymerization reactor system such as a gas-phase reactor system for production of polyolefin polymers. The methods comprise the step of compressing a gas stream having particulates entrained therein.

Abstract: A rotary feeder for feeding a particulate material including: a cylindrical housing comprising a feeder inlet, a first feeder outlet, and a second feeder outlet; a rotor mounted in the cylindrical housing including a plurality of substantially impeller blades defining a plurality of circumferentially spaced pockets alignable with the feeder inlet, first feeder outlet, and second feeder outlet, and adapted to sweep a wall of the cylindrical housing as the rotor rotates in the cylindrical housing; a device for rotating the rotor; and a separating screen in the first feeder outlet to substantially prevent oversize material from exiting through the first feeder outlet, wherein each of the plurality of circumferentially spaced pockets will align with the feeder inlet to receive therein a particulate material and an oversize material through the feeder inlet, rotate in the cylindrical housing to align with the first feeder outlet and discharge the particulate material therefrom, and rotate in the cylindrical housin