Abstract: Disclosed are high-pressure polymerization methods and systems using optimized operation sequence logic established at least partly from an analysis of a database containing data of previous operations. The optimized operation sequence logic and collected current process and system data are used to automate the operation of a high pressure ethylene polymerization process and unit.

Abstract: Apparatuses and processes that produce multimodal polyolefins, and in particular, polyethylene resins, are disclosed herein. This is accomplished by using two reactors in series, where one of the reactors is a multi-zone circulating reactor that can circulate polyolefin particles through two polymerization zones optionally having two different flow regimes so that the final multimodal polyolefin has improved product properties and improved product homogeneity.

Abstract: A method for removing contaminants from an process stream that includes the use of reticulated material to filter the process stream. The reticulated material also facilitate process stream flow distribution in process units. The reticulated material can be packed with a void space between a substantial number of the reticulated material that can be varied to enhance filtration and flow distribution. The method of filtering also provides a method of removing contaminants leaving process equipment. The methods can be used on a variety of process streams and process equipment. The reticulated material can include ceramics, metallic materials, and chemical vapor deposition elements. The reticulated material can be of various shapes and sizes, and can also be catalytically active.

Abstract: The present invention relates to a process for preparing a terephthalic diester by reacting terephthalic acid with at least one alcohol, wherein terephthalic acid is suspended in the alcohol in a dispersing tank, the preliminary suspension is passed from the dispersing tank into a reactor and converted in the presence of an esterification catalyst to obtain a reaction suspension, a stream of the reaction suspension is drawn off from the reactor, passed through a heat exchanger outside the reactor and heated and the heated reaction suspension is recycled into the reactor, and water of reaction is distilled off together with the vapor as alcohol-water azeotrope, the vapor is at least partly condensed, the condensate is separated into an aqueous phase and an organic phase and the organic phase is at least partly recycled into the reactor.

Abstract: An improved solution polymerization process wherein energy consumption is reduced comprising: i) injecting ethylene, solvent, catalyst, ?-olefins and hydrogen into at least one reactor to produce a polyethylene in a single liquid phase solution; ii) deactivating the single liquid phase solution; iii) passing the deactivated solution into a vapor/liquid separator forming a bottom stream of polyethylene rich solvent and a gaseous overhead stream; iv) passing not more than 40% of the gaseous overhead stream to distillation; v) condensing the remainder of the gaseous overhead stream to form a recycle stream, while generating low pressure steam; vi) passing the recycle stream through a means for oligomer removal; vii) passing the recycle stream through a lights separator; viii) passing the recycle stream through a purification step; ix) collecting the recycle stream in a recycle drum, passing the recycle stream through a pump and injecting a high pressure recycle stream into said reactors.

Abstract: Disclosed herein are improvements in recycle gas cooler systems in gas-phase polymerization processes that reduce the tendency for cooler fouling, including a recycle gas cooler system comprising a shell-and-tube heat exchanger. One or more of the tubes of the shell-and-tube heat exchanger may have a flared tube inlet at the tube sheet. The shell-and-tube heat exchanger may also be coupled to a straight inlet pipe having a length that is either at least about 5 times the inner diameter of the straight inlet pipe or at least about 15 feet, whichever is greater.

Abstract: Process for the gas phase polymerization of olefins, in particular, with recycle of fines to the reaction zone. The process includes (a) polymerizing an olefin in a reaction zone in which a bed of polymer particles is maintained in an agitated state by passing a fluid stream through the bed, (b) withdrawing the fluid stream from the reactor after it has passed through the bed of polymer particles, (c) separating entrained solids from the withdrawn fluid stream, and (d) returning the separated entrained solids to the reaction zone. The polymer production rate of the process is at least 40 tonnes/hour, and the separated solids from step (c) are returned to the lower half of the bed of polymer particles in the reaction zone.

Abstract: The present invention relates to a method of producing a polymer in the method for producing a copolymer of olefin and a polar group-containing monomer represented by formula (1): C(R1)2?C(R1)(C(R1)2)nR2??(1) (in the formula, the symbols have the same meanings as described in the description), the method comprising using a complex of a metal in Group 10 of the periodic table as a catalyst; and supplying a catalyst solution separated from a polymer after the polymerization reaction to a polymerization reaction system to recycle and re-use the catalyst. The production method of the present invention can dramatically reduce the catalyst cost.

Abstract: A method of making a pure block copolymer includes forming a crude block copolymer; heating a solution of the crude block copolymer and alcohol; and cooling the solution to promote precipitation of a purified block copolymer, wherein an amount of impurities remaining in the purified block copolymer is from about 0 to about 5 wt % based on a total weight of the purified block copolymer; a ratio of a polydispersity index of the crude block copolymer to a polydispersity index of the purified block copolymer is from about 1.02 to about 1.25; a ratio of a molecular weight of the crude block copolymer to a molecular weight of the purified block copolymer is from about 0.75 to about 1.0; and a ratio of a number average molecular weight of the crude block copolymer to a number average molecular weight of the purified block copolymer is from about 0.65 to about 1.

Abstract: Process and apparatus for recovering polymer from a gas phase reactor having a distribution plate via an outlet vessel comprising at least one apparatus for the breakup of polymeric agglomerates, the apparatus further comprising a feed pipe connecting the gas phase reactor and the outlet vessel a return gas line connecting the gas phase reactor and the outlet vessel, means for varying the flow rate through the return gas line from the outlet vessel to the gas phase reactor, and means for varying the outlet rate of polymer product from the outlet vessel.

Abstract: Process for the continuous transition between two ethylene copolymers containing a different comonomer. In particular, the process is for the continuous transition between two ethylene copolymers containing a different comonomer.

Abstract: The present disclosure provides a process for producing low density polyethylene with a dissipation factor less than or equal to 1.48×10?4 radian at 2.47 GHz. The process includes free radical high pressure polymerization of ethylene and separation of the unreacted species from the resultant polyethylene to form a recycle stream. The process further includes purging dissipative components from the recycle stream. The purged recycle stream is then introduced into the polymerization reactor.

Abstract: Heterophasic polypropylene copolymers having an MFR (2.16 kg, 230° C.) of 15 to 200 g/10 min, determined according to ISO 1133 comprising a propylene homo- or copolymer matrix with an MFR (2.16 kg, 230° C.) of 80 to 500 g/10 min, determined according to ISO 1133 (A) and an ethylene or C4-C10-alpha-olefin propylene rubber phase (B) dispersed within the matrix, wherein the heterophasic polypropylene resin has a fraction soluble in p-xylene at 25° C. (XCS), having an intrinsic viscosity of 2.85 to 4.00 dl/g, determined according to DIN EN ISO 1628-1 and -3 and being composed of propylene monomer units in an amount of 70 wt % to 90 wt %, with optimum balance of impact resistance and low amount of hexane extractables; a process for their preparation and their use.

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: Apparatus and process for gas phase polymerisation of olefins. The apparatus includes (a) a reaction zone having a grid at its base, (b) an inlet located in the lower half of the reaction zone for introducing a reaction gas to the reaction zone, (c) an outlet located in the upper half of the reaction zone for removing the reaction gas from the reaction zone, and (d) a solids separation unit having an inlet fluidly connected to the outlet for removing the reaction gas from the reaction zone. The inlet of the solids separation unit is located at a vertical height lower than the outlet for removal of reaction gas from the reaction zone and such that the angle to the horizontal of a straight line drawn between the inlet of the solids separation unit and the outlet for removal of reaction gas from the reaction zone is greater than 20°.

Abstract: There are disclosed a regenerated rubber, a method and apparatus for obtaining regenerated rubbers from vulcanized crumb rubber, such as rubber from scrap. The apparatus is a thermokinetic mixer having the particularity to have an air tight stationary chamber with inner non-uniform surface. The method comprises the steps of raising the speed of the rotor shaft in order to increase a temperature of a mixture made of vulcanized crumb rubber and a lubricant, such as oil, until a devulcanizing temperature is reached; and reducing the temperature of the mixture to a lower temperature during a second period of time. The method of the invention is environmentally friendly or “green”, since the regeneration method does not use chemicals, includes a shorter period of treatment at higher temperature avoiding the risks of rubber cracking and spontaneous combustion, and further allowing mass-production of regenerated rubber with lower energy consumption.

Abstract: An S,S- and R,R-lactide stream suitable for polymerization is prepared by producing a low molecular weight poly(lactic acid), depolymerizing the low molecular weight poly(lactic acid) to form a mixture of S,S-, R,R- and meso-lactide, and separating meso-lactide from this mixture to form an S,S- and R,R-lactide stream. Meso-lactide is recycled into the process, and shifts the mole fractions of the lactides in the lactide mixture that is produced.

Abstract: The present invention provides a highly efficient process for manufacturing copolyether glycol having a mean molecular weight of from about 650 to about 5000 dalton by polymerization of tetrahydrofuran and at least one alkylene oxide in the presence of an acid catalyst and at least one compound containing reactive hydrogen atoms. More particularly, the invention relates to a process for manufacturing copolyether glycol which comprises recycle to the polymerization reaction step of at least a portion of the oligomeric cyclic ether which is co-produced with the copolyether glycol, said process exhibiting an Space Time Yield value of greater than about 0.9.

Abstract: 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.

Abstract: The instant invention provides a composition suitable for stretch hood, method of producing the same, and articles made therefrom. The article according to the present invention comprises a multi-layer film according to the present invention has a thickness of at least 3 mils comprising at least one inner layer and two exterior layers, wherein the inner layer comprises at least 50 weight percent polyethylene copolymer having a melt index less than 2 grams/10 minutes, a density less than or equal to 0.910 g/cm3, a total heat of fusion less than 120 Joules/gram and a heat of fusion above 115° C. of less than 5 Joules/gram, the total heat of fusion of the inner layer less than the heat of fusion of either of the two exterior layers, and wherein the multi-layer film has an elastic recovery of at least 40% when stretched to 100% elongation.

Abstract: A manufacturing system for producing polyolefin includes a polymerization reactor, a flash chamber, and a purge column. In certain embodiments, the purge column may receive a solids stream directly from the flash chamber. Further, the purge column may function as a feed tank for an extruder within an extrusion/loadout system. According to certain embodiments, the manufacturing system may be configured to consume less than 445 kilowatt-hours of energy per metric ton of polyolefin produced based on consumption of electricity, steam, and fuel gas.

Abstract: A method for producing aqueous polymer dispersions by means of radically initiated emulsion polymerisation, in an aqueous medium, of vinyl ester and ethylene, in series-connected polymerisation reactors, wherein in a first discontinuous polymerisation phase at least some of the reactants are introduced into the first polymerisation reactor and the remainder is added in a metered fashion. The reactor is filled up to more than 90% by volume, and at least 90 wt % of the monomers are reacted; in a second continuous polymerisation phase, the reactants are continuously supplied to the first polymerisation reactor and product is continuously withdrawn, and the product is continuously transferred into a second polymerisation reactor, and in the second polymerisation reactor the polymerisation is continued until at least 98 wt % of the monomers used have reacted.

Abstract: A process for the preparation of a copolymer in semicontinuous operation in a polymerization apparatus including a polymerization reactor connected to a metering device, acid monomer being initially taken in the metering device and polyether macromonomer and water in the polymerization reactor, acid monomer being metered from the metering device via an acid monomer metering line into the polymerization reactor, a portion of the copolymer-containing aqueous medium being passed continuously during the free radical polymerization from the polymerization reactor via a reaction mixture line which is connected via a mixing device to the acid monomer metering line, the discharged copolymer-containing aqueous medium being mixed with the acid monomer in the mixing device during the metering of the acid monomer and being recycled to the polymerization reactor after the mixing via the acid monomer metering line.

Abstract: Polymer powder vessel having a silo including a main vertical cylinder and a hopper at the bottom of the cylinder, a polymer powder which occupies the full volume of the hopper and at least a part of the volume of the cylinder, a polymer powder silo inlet pipe connected to the silo at a height located above the polymer powder, and a polymer hopper withdrawal pipe is also connected to the hopper. The polymer powder hopper withdrawal pipe is also connected to the silo at a location above the polymer powder for recirculating a part of the polymer powder within the silo.

Abstract: An apparatus for manufacturing a polymer resin comprises a polymerization vessel, a bearing part, a protection part, a circulating cooling means, a raw material-injecting nozzle and a flow path-constituting part. The protection part forms a first flow path between the protection part and the side face of the agitation axis. The circulating cooling means includes a circulating inlet nozzle provided on a side face of the protruding part so as to be opposite to the protection part. The flow path-constituting part is provided between the bearing part and the protection part so as to cover the side face of the agitation axis, to fix the bearing part and the protection part. This flow path-constituting part forms a second flow path between the side face of the agitation axis and the flow path-constituting part and a third flow path for coupling the second flow path with the raw material-injecting nozzle.

Abstract: Polymerization process comprising the steps of: (a) reacting an aqueous suspension comprising initiator, vinyl chloride, and optionally one or more co-monomers in a continuous stirred tank reactor; and (b) further reacting the resulting suspension in at least one second reactor; wherein the conversion level of vinyl chloride in the continuous stirred tank reactor of step (a) is from 10 to 60 wt %.

Abstract: A sulfonic acid-functionalized vinyl alcohol copolymer is provided which is characterized by a substantial absence of compositional drift. The copolymer is produced by polymerization in two continuously-fed reaction zones such that the ratio of sulfonic acid-containing comonomer fed to the first reaction zone to the sulfonic acid-containing comonomer fed to the second reaction zone is within the range of about 55:45 to about 80:20. The resin is characterized by a resistance to irreversible dehydration upon exposure to harsh chemicals and by retention of hydroxide functionality upon aging. A resin composition comprising a copolymer lacking compositional drift is also provided for preparation of an oil and grease barrier coating, an oxidation resistant water soluble package, or a battery separator.

Abstract: The purpose of the present invention is to provide a method for collecting effective components from polyester fiber waste containing polyalkylene telephthalate as the main component, more specifically to provide a method for separating and removing foreign matters (mainly cotton) contained in polyester fiber waste. The purpose of the invention can be achieved by a method for separating and removing foreign matters from polyester waste, which includes throwing polyester fiber waste that contains polyalkylene telephthalate as the main component and foreign matters other than the polyalkylene telephthalate into a depolymerization reaction tank, subjecting a part or all of the polyester fiber to a depolymerization reaction with alkylene glycol to give a depolymerization reaction liquid, and then continuously or intermittently feeding the liquid to a foreign matter-separating and removing apparatus having specified characteristics.

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 process for preparing polyoxymethylene homopolymers or copolymers (7) by homopolymerization or copolymerization of trioxane, starting from methanol (1), in which methanol (1) is oxidized in a first reactor in a first production plant (A) to give an aqueous formaldehyde-comprising stream (2) which is fed to a second production plant (B) in which pure trioxane (6) is obtained and removal of low boilers (5) by distillation is carried out and the pure trioxane (6) is fed to a third production plant (C) in which it is homopolymerized or copolymerized to form polyoxymethylene homopolymers or copolymers (7), wherein the low boiler stream (5) from the low boiler removal column (K 2) is recycled to the feed stream into the first reactor in the first production plant (A), is proposed.

Abstract: A method for removing contaminants from a process stream that includes the use of reticulated material to filter the process stream in a vessel located upstream of a process unit. The reticulated material can be used with other conventional filter media within the vessel.

Abstract: The present invention relates to a process for the gas phase polymerisation of olefins, and, in particular, to a process for the gas phase polymerisation of olefins with recycle of fines to the reaction zone.

Abstract: A manufacturing system for producing polyolefin includes a polymerization reactor, a flash chamber, and a purge column. In certain embodiments, the purge column may receive a solids stream directly from the flash chamber. Further, the purge column may function as a feed tank for an extruder within an extrusion/loadout system. According to certain embodiments, the manufacturing system may be configured to consume less than 445 kilowatt-hours of energy per metric ton of polyolefin produced based on consumption of electricity, steam, and fuel gas.

Abstract: A method for producing a molded product consisting of a resin polymerized by a melt polycondensation reaction, comprising continuous feeding of a prepolymer in molten state from a prepolymer feeding port to a polymerization reactor, discharging from holes of a porous plate, followed by polymerization while dropping along a supporting substrate under reduced pressure, and molding by transferring to at least one molding machine in molten state without solidification, wherein transfer pressure to said molding machine is controlled so as to maintain at an arbitrary pressure from 0.1 to 100 MPa (absolute pressure).

Abstract: A process for the preparation of a chromium-type supported olefin polymerization catalyst. A fluidized bed of support particles in an inert carrier gas is established. A chromium (III) compound is added to the fluidized support particles to provide a supported catalyst component. The supported catalyst component is activated to convert at least a portion of the chromium (III) to Chromium (VI). The chromium (III) containing particles may be recovered from the fluidized bed and then activated or they may be activated in the fluidized bed. Also the support particles can be treated in the fluidized bed with other treatment agents. The support particles may be pretreated with a solution of a boron treating agent prior to incorporation of the support in the fluidized bed.

Abstract: 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.

Abstract: The present disclosure relates to a method for polymerizing polypropylene, optionally with one or more additional comonomers in a gas phase reactor in the presence of a mixed electron donor system comprising at least one selectivity control agent and at least one activity limiting agent. The process involves controlling the polymerization process to ensure that the difference between the reactor temperature and the dew point temperature of the incoming monomer stream is 12° C. or greater.

Abstract: The invention relates to a process for continuously producing thermoplastically processable polyurethanes in a recycle reactor with flexibly adjustable mixing conditions.

Abstract: Processes for making water-absorbent cross-linked polymers, such as polyacrylic acids/polyacrylates, using supercritical medium; and water-absorbent polymers, e.g. particles thereof, obtained by such processes, where such particles may be porous.

Abstract: Process for transferring a slurry stream containing polymer through a transfer line from a polymerisation reactor to a downstream vessel by, prior to entry into the downstream vessel, separating the slurry stream into two flows, the first flow being recycled upstream of the flow separation and the second flow being passed into the downstream vessel. The flow separation is located more than halfway along the transfer line between the reactor and the downstream vessel.

Abstract: A process for the polymerization of olefins carried out in a gas-phase reactor having interconnected polymerization zones, where the growing polymer particles flow upward through a first polymerization zone (riser) under fast fluidization or transport conditions, leave said riser and enter a second polymerization zone (downcomer) through which they flow downward under the action of gravity, leave said downcomer and are reintroduced into the riser, a gas recycle stream being withdrawn from said first polymerization zone, subjected to cooling below its dew point and then returned to said first polymerization zone, the process being characterized in that said gas recycle stream is cooled at a temperature Tc ranging from 0.05° C. to 3° C. below its dew point.

Abstract: Systems and methods for removing a volatile catalyst poison from a liquid hydrocarbon are provided. In one embodiment, a process vent (106) can be introduced to a vent recovery system (108) to provide a recycle gas (110). A first portion of the recycle gas (112) and a liquid hydrocarbon (102) can be introduced to a stripper column (104) to provide a stripper vent gas (114) and a degassed liquid hydrocarbon (116) that can be introduced to a polymerization process.

Abstract: A manufacturing process for producing polyolefin, having a feed system, a reactor system including at least one polymerization reactor, a diluent/monomer recovery system, a fractionation system, and an extrusion/loadout system having an extruder. The manufacturing process is configured to consume less than 325 kilowatt-hours of electricity per metric ton of polyolefin produced.

Abstract: The invention is directed to polyester processes that utilizes a pipe reactor in the esterification, polycondensation, or both esterification and polycondensation processes. Pipe reactor processes of the present invention have a multitude of advantages over prior art processes including improved heat transfer, volume control, agitation and disengagement functions.

Abstract: Process for controlling the (co)polymerization of olefins in a continuous polymerization reactor wherein the olefin (co)polymerization is performed in an industrial plant reactor in the presence of a polymerization catalyst characterized in that at least one operating parameter of the plant is controlled by means of a measurement of the chain branching level (CBL) of the produced polymer.

Abstract: The present invention relates to a process for the preparation of a copolymer in semicontinuous operation in a polymerization apparatus, comprising a polymerization reactor connected to a metering device, in each case acid monomer being initially taken in the metering device and polyether macromonomer and water in the polymerization reactor, acid monomer being metered from the metering device via an acid monomer metering line into the polymerization reactor, free radical polymerization initiator being passed into the polymerization reactor before and/or during the metering of the acid monomer into the polymerization reactor so that an aqueous medium in which acid monomer and polyether macromonomer are reacted with formation of the copolymer by free radical polymerization forms in the polymerization reactor, a portion of the copolymer-containing aqueous medium being passed continuously during the free radical polymerization from the polymerization reactor via a reaction mixture line which is connected via a mi

Abstract: A manufacturing process for producing polyolefin, having a feed system, a reactor system including at least one polymerization reactor, a diluent/monomer recovery system, a fractionation system, and an extrusion/loadout system having an extruder. The manufacturing process is configured to consume less than 325 kilowatt-hours of electricity per metric ton of polyolefin produced.

Abstract: Polyesters such as polyethylene, polypropylene and polybutylene terephthalate are made from melts of precondensates of polyesters by first conducting vapors comprising precondensate components distributed in the form of an aerosol through a polycondensation reactor in which precondensate components are deposited on the reactor wall and in an outlet chamber of the reactor on a separator. Then the deposits are conducted to the unstirred discharge sump. Upper layers of the discharge sump are continuously recirculated in the stirred reactor area and thus subjected to reconversion and further polycondensation.

Abstract: Olefin polymerisation process in which a slurry of olefin polymer is produced within a polymerisation zone, followed by withdrawing a polymer slurry stream from the polymerisation zone, and passing the polymer slurry stream through a transfer line to a centrifugal concentrating device which separates the polymer slurry stream into a solids-lean stream or streams each having a solids concentration less than that of the polymer slurry stream entering the concentrating device and a solids-rich stream or streams each having a solids concentration greater than that of the polymer slurry stream entering the concentrating device. At least part of the solids-rich stream or streams is recycled back into the polymer slurry stream upstream of the concentrating device and downstream of the polymerisation zone, and 2-60 vol % of the solids-rich slurry stream is recycled back into the polymer slurry stream upstream of the concentrating device.

Abstract: This invention relates to a process to polymerize olefins comprising contacting propylene, at a temperature of 65° C. to 150° C. and a pressure of 1.72 to 34.