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 method for cleaning a distributor plate in a fluidized bed polymerization reactor system according to one embodiment includes, in a first mode, operating with about a normal, baseline value of superficial gas velocity in a fluidized bed polymerization reactor system having a reactor vessel, a recycle line, and a distributor plate in the reactor vessel near an inlet of the reactor vessel. In a second mode, the superficial gas velocity is increased above the baseline value of the first mode to a level sufficient to raise the temperature of the cycle gas at the inlet above an average temperature of the cycle gas at the inlet in the first mode, and to a level sufficient to dislodge foulant from holes in the distributor plate.

Abstract: A catalyst system comprising a hafnocene catalyst compound and zirconocene catalyst compound, wherein the hafnocene and/or zirconocene include(s) at least one ligand substituted with at least one linear or iso alkyl group having 3 or more carbon atoms is provided. A process for polymerizing olefin(s) using the same catalyst system is also provided.

Abstract: A system and method for olefin polymerization is provided. The method includes polymerizing one or more olefins within a reactor having one or more injection tubes in fluid communication therewith, at least one of the one or more injection tubes having two or more concentric flow paths; flowing a catalyst through a first flow concentric path of the injection tube into the reactor; flowing one or more monomers through a second concentric flow path of the injection tube into the reactor; measuring rate of heat removal within the reactor; and adjusting the one or more monomers flow through the injection tube in response to the rate of heat removal in the reactor.

Abstract: A catalyst composition that includes a support material having an improved particle-size distribution is provided. Processes for producing polyolefin composition also are provided. Polymers and films also are provided. An example of a catalyst composition is a supported multi-transition-metal catalyst composition that includes: (a) at least two catalyst components selected from the group consisting of: a nonmetallocene catalyst component and a metallocene catalyst component; (b) a support material that has a D50 of less than about 30 microns and a particle size distribution having a D90/D10 ratio of less than about 6; and (c) an activator.

Abstract: A continuous gas phase circulating bed reactor, including: 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. Also disclosed is a polymerization process using such a circulating bed reactor.

Abstract: Catalyst compositions for the polymerization of olefins having improved flowability properties are provided.

Abstract: Embodiments of the present invention relate to measuring and controlling static in a gas phase reactor polymerization. In particular, embodiments relate to monitoring carryover static in an entrainment zone during gas phase polymerization to determine the onset of reactor discontinuity events such as chunking and sheeting. Embodiments also relate to monitoring carryover static to determine the need for effective additions of continuity additives that minimize reactor static activity and thereby preventing discontinuity events.

Abstract: A system for feeding a slurry catalyst composition including: a primary slurry feed system comprising a primary slurry flow meter and a primary catalyst injection device, wherein the primary slurry flow meter measures a primary slurry catalyst composition flow rate to the primary catalyst injection device; and a secondary slurry feed system comprising a secondary slurry flow meter, a secondary carrier liquid, a secondary carrier liquid control device, and a secondary catalyst injection device, wherein the secondary slurry flow meter measures a secondary slurry catalyst composition flow rate to the secondary catalyst injection device, wherein the secondary carrier liquid control device controls a process parameter of the secondary slurry feed system based a ratio of the primary slurry catalyst composition flow rate to the secondary slurry catalyst composition flow rate.

Abstract: A method for preparing a spray dried catalyst and a low viscosity, low foam spray dried catalyst system for olefin polymerization are provided. In one aspect, the method includes preparing a catalyst system including one or more components selected from metallocenes, non-metallocenes, and activators, adding mineral oil to the catalyst system to form a slurry, and adding one or more liquid alkanes having three or more carbon atoms to the slurry in an amount sufficient to reduce foaming and viscosity of the slurry. In one aspect, the catalyst system includes one or more catalysts selected from metallocenes, non-metallocenes, and a combination thereof, wherein the catalyst system is spray dried. The system further includes mineral oil to form a slurry including a catalyst system, and one or more liquid alkanes having three or more carbon atoms in an amount sufficient to reduce foaming and viscosity of the slurry.

Abstract: A method according to one embodiment includes operating a reactor or providing a reactor after operation, wherein the reactor includes a bottom section, a bed section above the bottom section, a distributor plate between the bottom section and the bed section, an expanded section above the bed section, and an upper section above the bed section, wherein the bed section has a height H measured from the distributor plate to the expanded section; measuring a concentration of particulates in the upper section of the reactor to obtain a first determined level of particulates in the upper section; and discharging at least some of the particulates from the reactor at an upper discharge point located above 0.55H as measured vertically from the distributor plate based on the first determined level. Additional systems and methods are also provided.

Abstract: Embodiments of the present invention relate to operating a gas-phase reactor at or near maximum production rates and to measuring and controlling polymer stickiness in a gas phase reactor polymerization. In particular, embodiments relate to monitoring acoustic emissions in a reactor during gas phase polymerization to determine the onset of reactor stickiness and possibly discontinuity events such as chunking and sheeting resulting from that stickiness. Embodiments also relate to monitoring acoustic emissions to determine the need for effective control of parameters that minimize reactor stickiness and thereby preventing discontinuity events. The emissions are processed by arithmetic averaging.

Abstract: Provided are various compositions, including but not limited to a bimodal polyethylene composition having a density of 0.940 g/cc or more, the composition comprising a high molecular weight polyethylene component and a low molecular weight polyethylene component, wherein the composition qualifies as a PE 100 material such that in accordance with ISO 1167 a pipe formed from the composition that is subjected to internal pipe resistance has an extrapolated stress of 10 MPa or more when the internal pipe resistance curve is extrapolated to 50 or 100 years in accordance with ISO 9080:2003(E), and wherein the melt strength is greater than 18 cN.

Abstract: Polyethylene compositions having improved properties are provided. In one aspect, a polyethylene composition having a long chain branching index (g?avg) of 0.5 to 0.9; a Melt Flow Rate (MFR) of greater than (49.011×MI(?0.4304)), where MI is Melt Index; and a weight average molecular weight to number average molecular weight (Mw/Mn) of less than or equal to 4.6 is provided.

Abstract: A system for feeding a slurry catalyst composition including: a primary slurry feed system comprising a primary slurry flow meter and a primary catalyst injection device, wherein the primary slurry flow meter measures a primary slurry catalyst composition flow rate to the primary catalyst injection device; and a secondary slurry feed system comprising a secondary slurry flow meter, a secondary carrier liquid, a secondary carrier liquid control device, and a secondary catalyst injection device, wherein the secondary slurry flow meter measures a secondary slurry catalyst composition flow rate to the secondary catalyst injection device, wherein the secondary carrier liquid control device controls a process parameter of the secondary slurry feed system based a ratio of the primary slurry catalyst composition flow rate to the secondary slurry catalyst composition flow rate.

Abstract: A process for the production of an ethylene alpha-olefin copolymer is disclosed. The process includes polymerizing ethylene and at least one alpha-olefin by contacting the ethylene and the at least one alpha-olefin with a metallocene catalyst in at least one gas phase reactor at a reactor pressure of from 0.7 to 70 bar and a reactor temperature of from 20° C. to 150° C. to form an ethylene alpha-olefin copolymer. The resulting ethylene alpha-olefin copolymer may have a density of 0.927 g/cc or greater and environmental stress crack resistance (ESCR) of 500 hr or more when measured according to ASTM 1693/B in 10% Igepal.

Abstract: An apparatus and method for melting polymer is provided. In at least one embodiment, the apparatus includes a housing, two or more rotatable members at least partially contained within the housing, where each rotatable member having a shaft coupled thereto. The apparatus also includes a motor having a drive shaft directly coupled to the shaft of the rotatable members such that the rotatable members rotate at a speed of the motor drive shaft. The rotatable members are preferably non-intermeshing and counter-rotating.

Abstract: The invention relates to catalyst compositions including at least one catalyst compound and at least one continuity additive such as poly-oxo-metal carboxylate compound and their use in the polymerization of olefins.

Abstract: Disclosed herein are various processes, including continuous fluidized-bed gas-phase polymerization processes for making a high strength, high density polyethylene copolymer, comprising (including): contacting monomers that include ethylene and optionally at least one non-ethylene monomer with fluidized catalyst particles in a gas phase in the presence of hydrogen gas at an ethylene partial pressure of 100 psi or more and a polymerization temperature of 105° C. or less to produce a polyethylene copolymer having a density of 0.945 g/cc or more and an ESCR Index of 1.0 or more wherein the catalyst particles are prepared at an activation temperature of 700° C. or less, and include silica, chromium, and titanium.

Abstract: Provided is a method for monitoring a polymerization reaction in a fluid bed reactor to determine in on-line fashion a current value, and preferably also a limiting value, of a stickiness control temperature, and optionally controlling the reaction in response thereto in an effort to prevent occurrence of a discontinuity event. The stickiness control temperature is a temperature indicative of a characteristic of melting behavior of polymer resin in the reactor, and may be indicative of occurrence of resin sheeting or another discontinuity event. Optionally , a predetermined relation between values of acoustic energy in the reactor and values of a stickiness control temperature in used to provide error checking for determination of the stickiness control temperature, or a current value of the stickiness control temperature is determined from acoustic data and a predetermined relation between values of an acoustic condition in the reactor and values of the stickiness control temperature.