Abstract: A process for preparing a homogeneous polyethylene product can include producing a first polyethylene resin in the presence of a metallocene catalyst in a reactor. The first polyethylene resin can have a density of from 0.940 to 0.970 g/cm3. The first polyethylene resin can have a Low Molecular Weight (LMW) with an MI2 of between 2 and 250 g/10 min. The process can include separately producing a second polyethylene resin in the presence of a Ziegler-Natta catalyst in a reactor. The second polyethylene resin can have a High Molecular Weight (HMW) with an MI2 of between 0.01 and 15 g/10 min. The process can include physically blending together the first polyethylene resin and the second polyethylene resin to produce the homogeneous polyethylene product.

Abstract: The invention relates to a process for preparing polyolefin in a loop reactor. The polymer is prepared by polymerizing olefin monomers in the presence of a catalyst to produce a polyolefin slurry while pumping said slurry through said loop reactor by means of a pump. The present process is characterized in that the catalyst is fed in the loop reactor at a distance to the pump. The invention allows production of the polymer with advantageous properties while leading to fewer blockages of the reactor.

Abstract: The present relates to a process for optimizing the recovery of unreacted monomers from a polymerization process, wherein said process comprises the steps of recovering a fluid stream generated by the separation of the polyolefin product from the polymerization fluid comprising unreacted monomers and optionally comonomers; contacting said fluid stream in an absorption zone with a scrub liquid comprising at least one C4-10 hydrocarbons, thereby absorbing at least a portion of the unreacted monomers in said scrub liquid; and withdrawing from said absorption zone (i) a vapor overhead comprising light gas and (ii) an absorber bottoms scrub liquid comprising said C4-10 hydrocarbons and said unreacted monomer; thereby recovering said unreacted monomer in said absorber bottoms scrub liquid comprising said C4-10 hydrocarbons.

Abstract: A process for preparing a homogeneous polyethylene product can include producing a first polyethylene resin in the presence of a metallocene catalyst in a reactor. The first polyethylene resin can have a density of from 0.942 to 0.970 g/cm3 and an HLMI of from 0.5 to 150 g/10 min. The process can include separately producing a second polyethylene resin in the presence of a chromium catalyst in a reactor. The process can include physically blending together the first polyethylene resin and the second polyethylene resin to produce the homogeneous polyethylene product. The homogeneous polyethylene product can include at least 25% by weight of the first polyethylene resin.

Abstract: A method for the copolymerization of ethylene and a C3+ olefin in a loop reactor and polymers formed therefrom are described herein. The method generally includes introducing an ethylene monomer, a C3+ olefin and a diluent carrier liquid into a loop reactor. A catalyst system can be supplied to said loop reactor. The diluent liquid, ethylene monomer, and C3+ olefin can be circulated through said loop reactor, while copolymerizing said ethylene and C3+ olefin in the presence of said catalyst system to produce a slurry. The slurry can be diverted into a settling leg, and sequentially discharged therefrom and withdrawn from said loop reactor. An ethylene monomer co-feed can be introduced into said loop reactor at spaced locations downstream of the ethylene and diluent. The ethylene co-feed can be introduced in an amount effective to reduce the variation in the ratio of ethylene and C3+ olefin.

Abstract: A process for preparing a polyolefin product can include providing a first high molecular weight (HMW) polyolefin resin having an HLMI of between 0.01 and 5 g/10 min, and separately providing a second low molecular weight (LMW) polyolefin resin having an MI2 of between 1 and 150 g/10 min. A device can be used to continuously physically melt and blend the first HMW polyolefin resin and the second LMW polyolefin resin to produce the polyolefin product. The device can include at least two feeding zones spatially separated and operably connected to each other. At least a art of the first HMW polyolefin resin is introduced in a first feeding zone, and at least a part of the second LMW polyolefin is introduced in a second feeding zone different from the first zone.

Abstract: A process for preparing a multimodal polyethylene product with at least two different polyethylene resins can include producing a first polyethylene resin in the presence of a Ziegler-Natta catalyst in a reactor. The Ziegler-Natta catalyst used for the production of the first polyethylene resin has an average particle size (D50) of at most 15 ?m. The HLMI of the first polyethylene resin is between 0.01 and 5 g/10 min. The process can include separately producing a second polyethylene resin in the presence of a Ziegler-Natta catalyst in a reactor. The MI2 of the second polyethylene resin is between 1 and 150 g/10 min. The process can include physically blending together the first and second polyethylene resins to produce a multimodal polyethylene product. The physical blending can be performed in a device for continuously melting and blending the first and second polyethylene resins.

Abstract: A method for the copolymerization of ethylene and a C3+ olefin copolymer in a loop reactor system and polymers formed therefrom are described herein.

Abstract: The present invention relates to a process of preparing a polyolefin in a loop reactor by introducing anti-fouling agent through a sleeve provided around at least part of the shaft of the pump. Also, the invention relates to the use of anti-fouling agent to prevent or reduce fouling by feeding the anti-fouling agent against the impeller of the pump upon introduction to the loop reactor.

Abstract: The invention relates to a process for preparing polyolefin in a loop reactor. The polymer is prepared by polymerizing olefin monomers in the presence of a catalyst to produce a polyolefin slurry while pumping said slurry through said loop reactor by means of a pump. The present process is characterized in that the catalyst is fed in the loop reactor at a distance to the pump. The invention allows production of the polymer with advantageous properties while leading to fewer blockages of the reactor.

Abstract: A method for the copolymerization of ethylene and a C3+ olefin copolymer in a loop reactor system and polymers formed therefrom are described herein.

Abstract: The present invention relates to a method for degassing polymer powder comprising flushing the polymer powder in a first chamber with a first flow of flushing gas, transferring the polymer powder into a second chamber and flushing the polymer powder with a second flow of flushing gas in said second chamber. The present invention also relates to a system suitable for carrying out this method.

Abstract: The present relates to a process for optimizing the recovery of unreacted monomers from a polymerization process, wherein said process comprises the steps of recovering a fluid stream generated by the separation of the polyolefin product from the polymerization fluid comprising unreacted monomers and optionally comonomers; contacting said fluid stream in an absorption zone with a scrub liquid comprising at least one C4-10 hydrocarbons, thereby absorbing at least a portion of the unreacted monomers in said scrub liquid; and withdrawing from said absorption zone (i) a vapor overhead comprising light gas and (ii) an absorber bottoms scrub liquid comprising said C4-10 hydrocarbons and said unreacted monomer; thereby recovering said unreacted monomer in said absorber bottoms scrub liquid comprising said C4-10 hydrocarbons.

Abstract: The present invention describes a reactor comprising two interconnected loops wherein the growing polymer flows continuously in circuit from the first loop to the second loop through a First pipe and back to the first loop through a second pipe. It also discloses process for polymerising olefins in two interconnected loop reactors.

Abstract: The present invention discloses the use of a chromium-based catalyst system in two serially connected loop reactors for copolymerising ethylene and a comonomer, at reduced productivity, the final polyethylene having a reduced amount of gel.

Abstract: The present invention relates to a method for degassing polymer powder comprising flushing the polymer powder in a first chamber with a first flow of flushing gas, transferring the polymer powder into a second chamber and flushing the polymer powder with a second flow of flushing gas in said second chamber. The present invention also relates to a system suitable for carrying out this method.

Abstract: The present invention relates to an apparatus for degassing polymer powder comprising a chamber having a first end and a second end opposite to each other, said chamber being equipped with at least one powder inlet and at least one gas outlet at the first end and with at least one powder outlet and at least one gas inlet at the second end, and a valve provided with a powder entry and a powder exit and arranged at the powder outlet of said chamber. The apparatus is characterised in that said chamber is equipped with a gas line joining a gas exit of the valve to the inside of the chamber at a position that is at a distance h2 from the first end (20), said distance h2 being 20-70% of the height H of the chamber and at a distance l1 from a wail of said chamber, said distance being l1 5-50% of the largest diameter L of the chamber.

Abstract: A method for controlling the injection of catalyst slurry in a polymerization reactor is described herein. The method includes the preparation of polyethylene with a solid catalyst and a hydrocarbon diluents. The method includes providing solid catalyst and a hydrocarbon diluent in one or more storage vessels such that a catalyst slurry is obtained in said vessel, transferring said catalyst slurry from said storage vessel to a mixing vessel wherein said catalyst slurry is diluted for obtaining a suitable concentration for use in a polymerization reaction, pumping said diluted catalyst slurry at a controlled flow rate from said mixing vessel to said polymerization reactor through one or more conduits, by means of a membrane pump provided in each of said conduits, and the membrane pump is controllable as a function of reactant concentration within the polymerization reactor.

Abstract: The present invention discloses the use of a chromium-based catalyst system in two serially connected loop reactors for copolymerising ethylene and a comonomer, at reduced productivity, the final polyethylene having a reduced amount of gel.

Abstract: The present invention describes a reactor comprising two interconnected loops wherein the growing polymer flows continuously in circuit from the first loop to the second loop through a First pipe and back to the first loop through a second pipe. It also discloses process for polymerising olefins in two interconnected loop reactors.