摘要:
A method of performing a polymerization reaction in a gas phase polymerization reactor to produce a bimodal polymer while controlling activity of a bimodal polymerization catalyst composition in the reactor by controlling concentration of at least one induced condensing agent (‘ICA’) in the reactor is provided. In some embodiments, the ICA is isopentane (or another hydrocarbon compound) and the bimodal catalyst composition includes a Group 15 and metal containing catalyst compound (or other HMW catalyst for catalyzing polymerization of a high molecular weight fraction of the product), and a metallocene catalyst compound (or other LMW catalyst for catalyzing polymerization of a low molecular weight fraction of the product).
摘要:
A method of performing a polymerization reaction in a gas phase polymerization reactor to produce a bimodal polymer while controlling activity of a bimodal polymerization catalyst composition in the reactor by controlling concentration of at least one induced condensing agent (‘ICA’) in the reactor is provided. In some embodiments, the ICA is isopentane (or another hydrocarbon compound) and the bimodal catalyst composition includes a Group 15 and metal containing catalyst compound (or other HMW catalyst for catalyzing polymerization of a high molecular weight fraction of the product), and a metallocene catalyst compound (or other LMW catalyst for catalyzing polymerization of a low molecular weight fraction of the product).
摘要:
A nozzle for catalyst injection for olefin polymerization is provided. In one or more embodiments the nozzle includes a first conduit including a body, a tapered section, and an injection tip. The nozzle also includes a second conduit having an inner surface and an outer surface. The first conduit is disposed about the second conduit defining a first annulus therebetween. The nozzle further includes a support member at least partially disposed about the outer surface of the first conduit defining a second annulus therebetween. The support member has a converging outer surface at a first end thereof.
摘要:
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.
摘要:
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.
摘要:
A process for the polymerization of olefins is disclosed. The process may include: feeding a catalyst, a liquid diluent, and an olefin to a polymerization vessel having, from a polymerization vessel bottom to a polymerization vessel top, a vapor introduction zone, a three-phase reaction zone and a vapor disengagement zone; contacting the catalyst and olefin under conditions of temperature and pressure in the presence of the liquid diluent as a continuous phase in the three-phase reaction zone to form a solid phase polyolefin; withdrawing a gas phase composition from an outlet in fluid communication with the vapor disengagement zone; circulating the gas phase composition through a gas circulation loop to an inlet in fluid communication with the vapor distribution zone at a rate sufficient to agitate the solid and liquid phases within the three-phase reaction zone; and withdrawing a reaction mixture comprising polyolefin and diluents from the three-phase reaction zone.
摘要:
Provided are systems and methods for separating a purge gas recovered from a polyethylene product. The method includes recovering a polyethylene product containing one or more volatile hydrocarbons from a polymerization reactor and contacting the polyethylene product with a purge gas to remove at least a portion of the volatile hydrocarbons to produce a polymer product having a reduced concentration of volatile hydrocarbons and a purge gas product enriched in volatile hydrocarbons. The purge gas product is compressed to a pressure of 2,500 kPaa to 10,000 kPaa, and is then cooled and separated into at least a first product, a second product, and a third product. A portion of one or more of the first, second, or third products is then recycled as a purge gas, to the polymerization reactor, or to the purge gas product enriched in volatile hydrocarbons prior to compression, respectively.
摘要:
A discharge system for removing a solid/gas mixture from a fluidized bed pressure vessel is provided. The system includes a fluidized bed pressure vessel, settling vessels, discharge lines, primary discharge valves, vent lines, primary vent valves, crosstie lines, crosstie valves, and primary exit valves wherein the system is absent a transfer tank, and absent a filter element. The method provides for transferring a solid/gas mixture via a discharge line from the pressure vessel to a settling vessel, wherein gas is separated from the mixture, and the gas is transferred to at least one other settling vessel via a crosstie line. After the solids are transferred out of the settling vessel, the empty vessel then receives gas from other settling vessels in the system.
摘要:
A discharge system for removing a solid/gas mixture from a fluidized bed pressure vessel is provided. The discharge system includes a fluidized bed pressure vessel, a settling vessel, a transfer vessel, discharge line, primary discharge valve, and primary exit valve. Also in included is a method to operate the discharge system. The method includes transferring a solid/gas mixture from a fluidized bed pressure vessel to a settling vessel, transferring the solids to a transfer vessel, and then emptying the transfer vessel.
摘要:
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.