Process for polymerizing olefin in a gas phase reactor with improved thermal homogeneity

    公开(公告)号:US12018102B2

    公开(公告)日:2024-06-25

    申请号:US17051204

    申请日:2019-05-29

    申请人: BOREALIS AG

    摘要: The present invention relates to a process for polymerizing at least one olefin in gas phase in a fluidized bed in a polymerization reactor having a top zone of a generally conical shape as such that the equivalent cross-sectional diameter is monotonically decreasing with respect to the flow direction of the fluidization gas, a middle zone in direct contact with and below said top zone of a generally cylindrical shape and a bottom zone in direct contact and below said middle zone and of a generally conical shape as such that the equivalent cross-sectional diameter is monotonically increasing with respect to the flow direction of the fluidization gas, comprising the steps of: a) introducing a first stream of fluidization gas into the bottom zone; b) polymerizing at least one olefin in the presence of a polymerization catalyst in the fluidized bed formed by particles of a polymer of the at least one olefin suspended in an upwards flowing stream of the fluidization gas in the middle zone; c) withdrawing a second stream comprising the fluidization gas and optionally particles of a polymer of the at least one olefin from the top zone; characterized in that the temperature of the particles of the polymer of the at least one olefin in the fluidized bed (TPP) does not exceed 120% of the operating temperature set point (TS) of the polymerization reactor, wherein TPP and TS are both given in ° C., and the use of said process for polymerizing an olefin homo- or copolymer having a narrow particle size distribution.

    A METHOD FOR RETURNING POLYMER TO A FLUIDISED BED REACTOR

    公开(公告)号:US20180369775A1

    公开(公告)日:2018-12-27

    申请号:US15776848

    申请日:2016-12-21

    申请人: Borealis AG

    IPC分类号: B01J8/18 B01J8/00 C08F110/02

    摘要: The present invention deals with a process of polymerising at least one olefin in a fluidised bed in a fluidised bed polymerisation reactor comprising a top zone, a middle zone in direct contact and below, a bottom zone in direct contact with and below the middle zone and wherein the reactor does not comprise a fluidisation grid. The process comprises passing a stream comprising the fluidisation gas and polymer particles into a separation step and withdrawing a stream comprising the polymer particles from the separation step and returning it to the polymerisation reactor. The process comprises adding a support gas stream to the stream comprising the polymer particles downstream of the separation step.

    System for Producing Polyolefin and Process for Recovering Polymerization Product from Gas Phase Reactor

    公开(公告)号:US20230001374A1

    公开(公告)日:2023-01-05

    申请号:US17773970

    申请日:2020-12-03

    申请人: Borealis AG

    摘要: The invention relates to a system for producing polyolefin. The system comprises a gas phase reactor (1) for polymerizing an olefin to obtain polymerization product. The gas phase reactor (1) comprises a gas distribution plate (11) arranged inside the gas phase reactor (1); a first outlet (12) for continuously withdrawing polymerization product from the gas phase reactor (1) as a first product stream, the first outlet (12) being arranged above the gas distribution plate (11); and a second outlet (13) for continuously withdrawing polymerization product from the gas phase reactor (1) as a second product stream, the second outlet (13) being arranged above the gas distribution plate (11). The system further comprises a first outlet tank (2) in fluid communication with the first outlet (12) via a first passage (22), wherein the first passage (22) comprises a first valve means (221) for controlling the flow of the first product stream in the first passage (22) and wherein the first outlet tank (2) is arranged to receive the first product stream and to concentrate the first product stream; a product receiver tank (3) in fluid communication with the second outlet (13) via a second passage (31), wherein the second passage (31) comprises a second valve means (311) for controlling the flow of the second product stream in the second passage (31), and wherein the product receiver tank (3) is arranged to receive the second product stream; and a control means in communication with the first valve means (221) and the second valve means (311) and arranged to control the operation of the first valve means (221) and the second valve means (311) so that flow in only one of the first passage (22) and the second passage (31) is allowed at a time.
    The invention relates also to a process for recovering polymerization product from a gas phase reactor (1). The gas phase reactor (1) is suitable for polymerizing an olefin to obtain polymerization product and comprises a gas distribution plate (11) arranged inside the gas phase reactor (1); a first outlet (12) for continuously withdrawing polymerization product from the gas phase reactor (1), the first outlet (12) being arranged above the gas distribution plate (11); and a second outlet (13) for continuously withdrawing polymerization product from the gas phase reactor (1), the second outlet (13) being arranged above the gas distribution plate (11). The process comprises selectively withdrawing polymerization product from the gas phase reactor (1) via the first outlet (12) as a first product stream, feeding the first product stream to a first outlet tank (2), and concentrating the first product stream in the first outlet tank (2); or withdrawing polymerization product from the gas phase reactor (1) via the second outlet (13) as a second product stream, and feeding the second product stream to a product receiver tank (3).

    Process and apparatus for removing polymer material from a gas-solids olefin polymerization reactor

    公开(公告)号:US11179690B2

    公开(公告)日:2021-11-23

    申请号:US16499361

    申请日:2018-05-30

    申请人: Borealis AG

    摘要: The present invention relates to a process for removing polymer material from a gas-solids olefin polymerization reactor wherein the gas-solids olefin polymerization reactor is connected to the top part of an outlet vessel via a feed pipe wherein the powder surface of discharged polymer material and the barrier gas injection point are situated in the outlet vessel as such to fulfill the following criteria: R′=X/Y≤2.0; and R″=X/D≥1.0; wherein X=Distance between the powder surface and the barrier gas injection point; Y=Distance between the barrier gas injection point and the vessel outlet; and D=Equivalent outlet vessel diameter, an apparatus for continuously removing polymer material comprising a gas-solids olefin polymerization reactor, an outlet vessel and a feed pipe connecting the gas-solids olefin polymerization reactor with the top part of the outlet vessel and the use of said apparatus for polymerizing alpha-olefin homo- or copolymers having alpha-olefin monomer units of from 2 to 12 carbon atoms and for increasing the barrier gas efficiency of the gas-solids olefin reactor to at least 75%.

    Process for preparing propylene copolymer compositions

    公开(公告)号:US10787528B2

    公开(公告)日:2020-09-29

    申请号:US16067170

    申请日:2016-12-27

    申请人: BOREALIS AG

    摘要: The present invention relates to an olefin polymerization process for producing propylene copolymer composition (P), wherein propylene, C4 to C10 α-olefin and optionally ethylene are reacted in the presence of a Ziegler-Natta catalyst in a multistage polymerization process comprising at least two polymerization reactors, wherein the copolymer composition is bimodal with respect to the content of C4 to C10 α-olefin and, if present, to ethylene. Further, the invention is directed to the propylene copolymer composition being bimodal with respect to the content of C4 to C10 α-olefin and optionally to ethylene, and use of said propylene copolymer compositions for producing articles.

    A PROCESS AND A MULTI-STAGE REACTOR ASSEMBLY FOR THE PRODUCTION OF POLYOLEFINS

    公开(公告)号:US20220234021A1

    公开(公告)日:2022-07-28

    申请号:US17616433

    申请日:2020-04-06

    申请人: Borealis AG

    摘要: A process for the production of polyolefins comprising: feeding a slurry comprising at least one polymerization catalyst, at least one carrier liquid, first olefin monomer(s) and optionally at least one first comonomer into at least one loop reactor; polymerizing the first olefin monomer(s) and optionally the at least one first comonomer yielding a first polyolefin; withdrawing the first polyolefin from the loop reactor; feeding the first polyolefin to a gas-solids olefin polymerization reactor, wherein the gas-solids olefin polymerization reactor comprises: a top zone; a middle zone, which comprises a top end in direct contact with said top zone and which is located below said top zone, the middle zone having a generally cylindrical shape; and a bottom zone, which is in direct contact with a bottom end of the middle zone and which is located below the middle zone; introducing a fluidization gas stream into the bottom zone of the gas-solids olefin polymerization reactor; polymerizing second olefin monomer(s) and optionally at least one second comonomer in the presence of the polymerization catalyst and the first polyolefin to a second polyolefin in a dense phase formed by particles of said second polyolefin suspended in an upwards flowing stream of the fluidization gas in the middle zone; introducing a jet gas stream through one or more jet gas feeding ports in a jet gas feeding area of the middle zone at the dense phase in the middle zone of the gas-solids olefin polymerization reactor; withdrawing the second polyolefin from the gas-solids olefin polymerization reactor.