Abstract: A system and method for polymerizing olefin in the presence of a chain transfer agent in a first reactor to form a first polyolefin, discharging from the first reactor a transfer slurry having the first polyolefin and the chain transfer agent, and processing the transfer slurry in a separator to remove chain transfer agent and to provide a fluff slurry having the first polyolefin and a lower content of chain transfer agent than in the transfer slurry. The system and method provide for feeding the fluff slurry to a second reactor, polymerizing olefin in the second reactor to form a second polyolefin, and discharging from the second reactor a slurry having the second polyolefin.

Abstract: The present invention discloses a continuous calcination vessel which can be used to prepare calcined chemically-treated solid oxides from solid oxides and chemically-treated solid oxides. A process for the continuous preparation of calcined chemically-treated solid oxides is also provided. Calcined chemically-treated solid oxides disclosed herein can be used in catalyst compositions for the polymerization of olefins.

Abstract: Silica-coated alumina activator-supports, and catalyst compositions containing these activator-supports, are disclosed. Methods also are provided for preparing silica-coated alumina activator-supports, for preparing catalyst compositions, and for using the catalyst compositions to polymerize olefins.

Abstract: A technique for polymerizing ethylene on catalyst in a first polymerization reactor and in a second polymerization reactor to form polyethylene particles, and controlling particle size of the polyethylene particles.

Abstract: The present invention discloses a continuous calcination vessel which can be used to prepare calcined chemically-treated solid oxides from solid oxides and chemically-treated solid oxides. A process for the continuous preparation of calcined chemically-treated solid oxides is also provided. Calcined chemically-treated solid oxides disclosed herein can be used in catalyst compositions for the polymerization of olefins.

Abstract: A system and method for polymerizing olefin in the presence of a chain transfer agent in a first reactor to form a first polyolefin, discharging from the first reactor a transfer slurry having the first polyolefin and the chain transfer agent, and processing the transfer slurry in a separator to remove chain transfer agent and to provide a fluff slurry having the first polyolefin and a lower content of chain transfer agent than in the transfer slurry. The system and method provide for feeding the fluff slurry to a second reactor, polymerizing olefin in the second reactor to form a second polyolefin, and discharging from the second reactor a slurry having the second polyolefin.

Abstract: A system and method for polymerizing olefin in the presence of a chain transfer agent in a first reactor to form a first polyolefin, discharging from the first reactor a transfer shiny having the first polyolefin and the chain transfer agent, and processing the transfer slurry in a separator to remove chain transfer agent and to provide a fluff slurry having the first polyolefin and a lower content of chain transfer agent than in the transfer slurry. The system and method provide for feeding the fluff slurry to a second reactor, polymerizing olefin in the second reactor to form a second polyolefin, and discharging from the second reactor a slurry having the second polyolefin.

Abstract: Multiple components are selected, conveyed, and measured in a polymerization system. A control system adjusts the system variables to the desired values. Portions of the components can be fed to a pre-contactor before introduction into the polymerization reactor. The catalyst component concentrations and residence times are tightly controlled in the pre-contactor to affect product properties. The pre-contactor can be a single or multiple combinations of a CSTR or plug flow pre-contactors.

Abstract: A system and method for polymerizing olefin in the presence of a chain transfer agent in a first reactor to form a first polyolefin, discharging from the first reactor a transfer slurry having the first polyolefin and the chain transfer agent, and processing the transfer slurry in a separator to remove chain transfer agent and to provide a fluff slurry having the first polyolefin and a lower content of chain transfer agent than in the transfer slurry. The system and method provide for feeding the fluff slurry to a second reactor, polymerizing olefin in the second reactor to form a second polyolefin, and discharging from the second reactor a slurry having the second polyolefin.

Abstract: A system and method for a first reactor to produce a transfer slurry having a first polyolefin polymerized in the first reactor, a heat-removal zone to remove heat from the transfer slurry, and a second reactor to receive the transfer slurry cooled by the heat-removal zone, the second reactor to produce a product slurry having a product polyolefin which includes the first polyolefin and a second polyolefin polymerized in the second reactor.

Abstract: Techniques are provided for catalyst preparation. A system for catalyst preparation may include an agitator disposed inside a polymerization catalyst tank and configured to mix a polymerization catalyst and a solvent to generate a polymerization catalyst solution. The system may also include a heating system coupled to the polymerization catalyst tank and configured to maintain a temperature of the polymerization catalyst solution above a threshold. The system may also include a precontactor configured to receive feed streams comprising an activator and the polymerization catalyst solution from the polymerization catalyst tank to generate a catalyst complex. The system may also include a transfer line configured to transfer the catalyst complex from an outlet of the precontactor to a reactor.

Abstract: A system and method for producing polyolefin, including a polyolefin reactor system having: a first reactor to produce a first reactor discharge stream having a first polyolefin and a first diluent; and a second reactor to receive at least a portion of the first reactor discharge stream and to produce a second reactor discharge stream having a second polyolefin and a second diluent, wherein the second diluent is different than the first diluent.

Abstract: Techniques are provided for catalyst preparation. A system for catalyst preparation may include an agitator disposed inside a polymerization catalyst tank and configured to mix a polymerization catalyst and a solvent to generate a polymerization catalyst solution. The system may also include a heating system coupled to the polymerization catalyst tank and configured to maintain a temperature of the polymerization catalyst solution above a threshold. The system may also include a precontactor configured to receive feed streams comprising an activator and the polymerization catalyst solution from the polymerization catalyst tank to generate a catalyst complex. The system may also include a transfer line configured to transfer the catalyst complex from an outlet of the precontactor to a reactor.

Abstract: A system and method for producing polyolefin, including a polyolefin reactor system having: a first reactor to produce a first reactor discharge stream having a first polyolefin and a first diluent; and a second reactor to receive at least a portion of the first reactor discharge stream and to produce a second reactor discharge stream having a second polyolefin and a second diluent, wherein the second diluent is different than the first diluent.

Abstract: A method comprising contacting an olefin in the presence of a catalyst and a melt index modifier (MIM) under conditions suitable to form a polyolefin and recovering the polyolefin, wherein the polyolefin melt index is increased by at least about 25%, wherein the normalized catalyst activity is decreased by less than about 10%, and wherein the MIM is characterized by the general formula R1—HC?CH—R2 or R3R4C?CH2 where R1, R2, R3, R4 are each selected from the group consisting of a non-aromatic organyl group.

Abstract: Methods and systems for preparing catalyst, such as chromium catalysts, are provided. The valence of at least a portion of the catalyst sent to an activator is changed from Cr(III) to Cr(VI). The catalyst is prepared or activated continuously using a fluidization bed catalyst activator.

Abstract: Systems and methods for the maintenance of active chromium-based catalysts and their use in polymerization processes are described. In one embodiment, a system for the introduction of multiple polymerization components to activate a chromium based catalyst within a mix tank is described. Other described features may include materials and methods to purify the liquid medium of a catalyst slurry so that the catalyst slurry maintains a high level of activity. The active chromium-based catalyst may provide polyolefins with a number of desirable properties in a reliable, consistent, and predictable manner.

Abstract: A system and method for polymerizing olefin in the presence of a chain transfer agent in a first reactor to form a first polyolefin, discharging from the first reactor a transfer slurry having the first polyolefin and the chain transfer agent, and processing the transfer slurry in a separator to remove chain transfer agent and to provide a fluff slurry having the first polyolefin and a lower content of chain transfer agent than in the transfer slurry. The system and method provide for feeding the fluff slurry to a second reactor, polymerizing olefin in the second reactor to form a second polyolefin, and discharging from the second reactor a slurry having the second polyolefin.

Abstract: A technique for polymerizing ethylene on catalyst in a first polymerization reactor and in a second polymerization reactor to form polyethylene particles, and controlling particle size of the polyethylene particles.

Abstract: A polyolefin production system including: a first reactor configured to produce a first discharge slurry having a first polyolefin; a second reactor configured to produce a second discharge slurry having a second polyolefin; and a post-reactor treatment zone having at least a separation vessel configured to receive the second discharge slurry or both the first discharge slurry and the second discharge slurry.