Abstract: An apparatus and method for removing polymer solids from a slurry loop reactor. A discharge conduit having a longitudinal axis and an end section for removing polymer solids from the slurry loop reactor is provided. The discharge conduit is attached to the slurry loop reactor so that the longitudinal axis and at least a portion of an outer wall of the slurry loop reactor form an angle of less than about 90 degrees. The end section includes a first edge and a second edge that extends past at least a portion of an inner wall of the slurry loop reactor into a liquid reactor slurry. Polymer solids contained within the liquid reactor slurry are concentrated on the second edge so that an average polymer solids concentration in the discharge slurry is greater than an average polymer solids concentration of the liquid reactor slurry within the slurry loop reactor.

Abstract: A process and apparatus for separating polymer solids, hydrocarbon fluids, and purge gas in an intermediate pressure zone and a purge zone. The purge gas in the purge zone is used to remove hydrocarbon fluids from the polymer solids, and a stream containing the purge gas and hydrocarbons is passed to a hydrocarbon/purge gas recovery zone. High-purity purge gas from the recovery zone is efficiently used by passing a portion back to the purge zone and another portion to an extruder feed zone. Hydrocarbon fluids separated from polymer solids in the intermediate pressure zone and in the hydrocarbon/purge gas recovery zone are liquefied and passed to a recycle zone, and the hydrocarbons (typically liquid diluent and/or unreacted monomer) are recycled to the reactor without fractionation.

Abstract: A recycling and recovery system and process comprising a flash gas separator that receives a slurry comprising liquid medium and solid polymer particles. The flash gas separator separates the diluent from the solid polymer particles as a vapor stream comprising at least diluent and heavies. A line receives the vapor stream from the flash gas separator. The line leads to a heavies removal system that yields a liquid that is relatively concentrated in heavies and a diluent vapor that is relatively free of heavies. The liquid is passed to a heavies column while the diluent vapor is passed to a diluent recycle chamber and then recycled to a slurry polymerization reactor without additional treatment to remove heavies.

Abstract: A polymerization loop reactor including a loop reaction zone, a continuous takeoff, and a fluid slurry disposed in the reaction zone. A generally cylindrical wall defines the loop reaction zone. The length of the loop reaction zone and the nominal outside diameter of the generally cylindrical wall define a length/diameter ratio greater than 250. The reactor can be charged with a fluid slurry including an olefin monomer reactant, solid olefin polymer particles, and a liquid diluent. The concentration of the solid olefin polymer particles in the slurry can be greater than 40 weight percent based on the weight of polymer particles and the weight of liquid diluent. Also disclosed is a polymerization process carried out by polymerizing, in the loop reaction zone of a reactor as defined above, at least one olefin monomer in a liquid diluent to produce a fluid slurry as defined above.

Abstract: A process is provided that produces polyolefins. The process comprises mixing a first stream, which comprises at least one catalyst deactivating agent, with a second stream, which comprises at least one polyolefin, at least one catalyst, at least one diluent, and at least one monomer, to produce a third stream, which comprises at least one polyolefin, at least one deactivated catalyst, at least one diluent, and at least one monomer. By utilizing the deactivating agent, polymerization can be slowed, or substantially stopped, when downstream equipment is being repaired or process control problems are being corrected. Later, polymerization can be restarted without the use of scavengers to remove poisons from the slurry polymerization reactor, and polyolefin production can be resumed.

Abstract: A process is provided that produces polyolefins.

Abstract: Polymer solids are maintained in an intermediate pressure zone for a desired polymer solids residence time and then transferred to a purge zone or other lower pressure zone. An increase in the polymer solids residence time in the intermediate pressure zone allows more diluent to flash or separate, thereby avoiding or reducing the need for a low pressure flash zone. A fluff chamber may be disposed between the intermediate pressure zone and a lower pressure zone. A transporter tank may be used to transport polymer solids after the intermediate pressure zones.

Abstract: A catalyst slurry for a polymerization reactor can be prepared in a mixing tank and the catalyst slurry fed to one or more storage tanks. The storage tanks can include agitators so that the catalyst slurry is maintained at an essentially homogeneous solids-to-liquid ratio. From the storage tank(s), the catalyst slurry can be pumped to the polymerization reactor along a fluid passage having a flow meter. The flow of the catalyst slurry can be continuous and/or adjusted based on a measured parameter. The catalyst slurry may be continuously and reliability fed to the polymerization reactor.

Abstract: Polymer solids are maintained in an intermediate pressure zone for a desired polymer solids residence time and then transferred to a purge zone or other lower pressure zone. An increase in the polymer solids residence time in the intermediate pressure zone allows more diluent to flash or separate, thereby avoiding or reducing the need for a low pressure flash zone. A fluff chamber may be disposed between the intermediate pressure zone and a lower pressure zone transporter tank may be used to transport polymer solids after the intermediate pressure zone.

Abstract: A process is provided that produces polyolefins.

Abstract: A recycling and recovery system and process comprising a flash gas separator that receives a slurry comprising liquid medium and solid polymer particles. The flash gas separator separates the diluent from the solid polymer particles as a vapor stream comprising at least diluent and heavies. A line receives the vapor stream from the flash gas separator. The line leads to a heavies removal system that yields a liquid that is relatively concentrated in heavies and a diluent vapor that is relatively free of heavies. The liquid is passed to a heavies column, while the diluent vapor is passed to a diluent recycle chamber and then recycled to a slurry polymerization reactor without additional treatment to remove heavies.

Abstract: An improved polymerization process includes withdrawing a portion of a fluid slurry through a plurality of active continuous take off mechanisms, monitoring the pressure of feed material fed to the reactor, and adjusting the continuous take off mechanisms in response to the monitored feed line pressure.

Abstract: A process is provided that produces polyolefins. The process comprises mixing a first stream, which comprises at least one catalyst deactivating agent, with a second stream, which comprises at least one polyolefin, at least one catalyst, at least one diluent, and at least one monomer, to produce a third stream, which comprises at least one polyolefin, at least one deactivated catalyst, at least one diluent, and at least one monomer. By utilizing the deactivating agent, polymerization can be slowed, or substantially stopped, when downstream equipment is being repaired or process control problems are being corrected. Later, polymerization can be restarted without the use of scavengers to remove poisons from the slurry polymerization reactor, and polyolefin production can be resumed.

Abstract: A process and apparatus for separating polymer solids, hydrocarbon fluids, and purge gas in an intermediate pressure zone and a purge zone. The purge gas in the purge zone is used to remove hydrocarbon fluids from the polymer solids, and a stream containing the purge gas and hydrocarbons is passed to a hydrocarbon/purge gas recovery zone. High-purity purge gas from the recovery zone is efficiently used by passing a portion back to the purge zone and another portion to an extruder feed zone. Hydrocarbon fluids separated from polymer solids in the intermediate pressure zone and in the hydrocarbon/purge gas recovery zone are liquefied and passed to a recycle zone, and the hydrocarbons (typically liquid diluent and/or unreacted monomer) are recycled to the reactor without fractionation.

Abstract: An olefin polymerization process wherein monomer, diluent and catalyst are circulated in a continuous loop reactor and product slurry is withdrawn and passed through a heated conduit to a cyclone. The cyclone allows better separation of vaporized diluent. In a preferred embodiment, the slurry is heated in a flashline heater so that a high percentage of the withdrawn diluent is vaporized. The vaporized diluent and concentrated intermediate product are passed to a cyclone where a majority of the vaporized diluent is separated and thereafter condensed by heat exchange, without compression, and recycled to the reactor. Also an apparatus for separating vaporized diluent and polymer particles using a cyclone.

Abstract: A catalyst slurry for a polymerization reactor can be prepared in a mixing tank and the catalyst slurry fed to one or more storage tanks. The storage tanks can include agitators so that the catalyst slurry is maintained at an essentially homogeneous solids-to-liquid ratio. From the storage tank(s), the catalyst slurry can be pumped to the polymerization reactor along a fluid passage having a flow meter. The flow of the catalyst slurry can be continuous and/or adjusted based on a measured parameter. The catalyst slurry may be continuously and reliability fed to the polymerization reactor.

Abstract: An improved polymerization process includes withdrawing a portion of a fluid slurry through a plurality of active continuous take off mechanisms, monitoring the pressure of feed material fed to the reactor, and adjusting the continuous take off mechanisms in response to the monitored feed line pressure.

Abstract: A slurry polymerization process wherein olefin monomer is fed to a continuous loop reactor at two or more points, allowing operation at higher and steadier monomer concentrations in the circulating slurry. A loop reactor apparatus has two or more monomer feeds and may have two or more catalyst feeds and/or two or more product take-offs, and each feed may have its own associated control scheme.

Abstract: A recycling and recovery system and process comprising a flash gas separator that receives a slurry comprising liquid medium and solid polymer particles. The flash gas separator separates the diluent from the solid polymer particles as a vapor stream comprising at least diluent and heavies. A line receives the vapor stream from the flash gas separator. The line leads to a heavies removal system that yields a liquid that is relatively concentrated in heavies and a diluent vapor that is relatively free of heavies. The liquid is passed to a heavies column, while the diluent vapor is passed to a diluent recycle chamber and then recycled to a slurry polymerization reactor without additional treatment to remove heavies.

Abstract: Polymer solids are maintained in an intermediate pressure zone for a desired polymer solids residence time and then transferred to a purge zone or other lower pressure zone. An increase in the polymer solids residence time in the intermediate pressure zone allows more diluent to flash or separate, thereby avoiding or reducing the need for a low pressure flash zone. A fluff chamber may be disposed between the intermediate pressure zone and a lower pressure zone transporter tank may be used to transport polymer solids after the intermediate pressure zone.

Abstract: A vacuum pump comprises a slide shaft having one end provided with a discharging valve and a diaphragm, a cam plate in press-contact with the other end of the slide shaft to cause reciprocating movement of the slide shaft, a shaft of a motor for rotating the cam plate and a bearing casing for holding a bearing which supports the motor shaft in a freely rotatable manner, wherein the cam plate is provided at its one side surface with a recess for receiving the bearing and provided at its other side surface with a cam surface.