Polymerization process

Patent metadata

Field	Value
Publication number	US-2016168288-A1
Application number	US-201314909505-A
Country	US
Kind code	A1
Filing date	Aug 14, 2013
Priority date	Aug 14, 2013
Publication date	Jun 16, 2016
Grant date	—

Abstract

The present invention relates to a process for the introduction of liquid feeds to a polymerisation process, and in particular provides a process for the introduction of a fresh feed selected from fresh comonomer and fresh inert hydrocarbon to a polymerisation reactor, which polymerisation reactor is part of a polymerisation process comprising high and low pressure recovery systems, said high pressure recovery system being at a pressure of 0.5 MPa or above and said low pressure recovery system being at a pressure of less than 0.5 MPa, which process comprises passing said fresh feed and a process stream comprising a first component selected from hydrogen, nitrogen and methane and a second component which is a monomer to a separator which is part of the low pressure recovery system and is at a pressure of 0.4 MPa or less to produce a first stream comprising the majority of the first component and a second stream comprising the second component and the majority of the fresh feed, and passing the second stream to the polymerisation reactor.

First claim

1 - 16 . (canceled)

17 . A process for the introduction of a fresh feed selected from fresh comonomer and fresh inert hydrocarbon to a polymerisation reactor wherein the polymerisation reactor is part of a polymerisation process comprising high and low pressure recovery systems, said high pressure recovery system being at a pressure of 0.5 MPa (5 bar) or above and said low pressure recovery system being at a pressure of less than 0.5 MPa (5 bar), which process comprises passing said fresh feed and a process stream comprising a first component selected from hydrogen, nitrogen and methane and a second component which is a monomer to a separator which is part of the low pressure recovery system and is at a pressure of 0.4 MPa or less to produce a first stream comprising the majority of the first component and a second stream comprising the second component and the majority of the fresh feed, and passing the second stream to the polymerisation reactor.

18 . A process according to claim 17 where the fresh feed is fresh comonomer.

19 . A process according to claim 17 where the separator is a single stage separation vessel.

20 . A process according to claim 17 wherein the polymerisation reactor is a slurry phase reactor and the fresh inert hydrocarbon is a component which is utilised as a diluent in the process.

21 . A process according to claim 17 wherein both fresh comonomer and fresh inert hydrocarbon are passed to the separator with the process stream.

22 . A process according to claim 17 where the separator is at a temperature of less than 0° C., for example less than −10° C., and most preferably less than −20° C., for example −35° C. and/or where the separator is at a pressure of 0.3 MPa or less, and most preferably 0.2 MPa or less.

23 . A process according to claim 17 wherein the majority of fresh comonomer passed to the reactor is passed via the claimed process and/or the majority of fresh inert hydrocarbon passed to the reactor is passed via the claimed process, and preferably wherein all of the fresh comonomer passed to the reactor is passed via the claimed process.

24 . A process for the treatment of a fresh feed stream to be introduced into a polymerisation reactor, said process comprising
a) Passing the fresh feed stream to a first treatment step where it is treated to remove one or more impurities, and b) Passing the fresh feed stream exiting the first treatment step with a process stream comprising a first component selected from hydrogen, nitrogen and methane and a second component which is a monomer to a second treatment step which is a separator to produce a first stream comprising the majority of the first component and a second stream comprising the second component and the majority of the fresh feed, and c) Passing the second stream to the polymerisation reactor.

25 . A process according to claim 24 wherein the fresh feed comprises inert hydrocarbon or comonomer.

26 . A process according to claim 24 wherein the polymerisation reactor is a slurry loop polymerisation reactor to which inert hydrocarbon is fed as a diluent.

27 . A process according to claim 24 wherein the polymerisation reactor is part of a polymerisation process comprising high and low pressure recovery systems, said high pressure recovery system being at pressure of 0.5 MPa or above and said low pressure recovery system being at pressure of less than 0.5 MPa, the separator being part of the low pressure recovery system and being at a pressure of 0.4 MPa or less.

28 . A process according to claim 27 wherein the separator is at a temperature of less than 0° C., for example less than −10° C., and most preferably less than − 20 ° C., for example −35° C. and/or where the separator is at a pressure of 0.3 MPa or less, and most preferably 0.2 MPa or less.

29 . A process according to claim 17 wherein the polymerisation process comprises the steps of:
1) Polymerising a monomer and a comonomer in a polymerisation reactor,
2) Withdrawing an effluent stream comprising solid polymer and a mixture comprising unreacted monomer and unreacted comonomer, and passing the effluent to a high pressure recovery system comprising
a. a high pressure separation step for separating a vapour comprising unreacted monomer and unreacted comonomer from said solids, and
b. a recycle system for recycling at least a portion of the vapour to the polymerisation reactor,

3) Passing the solids from the high pressure recovery system to a low pressure recovery system comprising
a. a low pressure separation step for separating further unreacted monomer and unreacted comonomer from said solids, and
b. a recycle system comprising a vapour/liquid separator for recycling at least a portion of the unreacted monomer and unreacted comonomer,

said separator to which the fresh feed is passed being the “vapour/liquid separator” of step 3(b).

30 . A process according to claim 29 wherein a portion of the vapour recovered in step 2(a) is condensed, let-down in pressure, and also passed to the vapour/liquid separator of step 3(b).

31 . A process according to claim 17 wherein the polymerisation reactor has a volume of at least 50 m 3 .

32 . A process according to claim 17 wherein less than 50 wt % of the second component (monomer) is recovered in the second stream.

33 . A process according to claim 24 wherein the polymerisation reactor has a volume of at least 50 m 3 .

34 . A process according to claim 27 wherein the polymerisation process comprises the steps of:
1) Polymerising a monomer and a comonomer in a polymerisation reactor,
2) Withdrawing an effluent stream comprising solid polymer and a mixture comprising unreacted monomer and unreacted comonomer, and passing the effluent to a high pressure recovery system comprising
a. a high pressure separation step for separating a vapour comprising unreacted monomer and unreacted comonomer from said solids, and
b. a recycle system for recycling at least a portion of the vapour to the polymerisation reactor,

3) Passing the solids from the high pressure recovery system to a low pressure recovery system comprising
a. a low pressure separation step for separating further unreacted monomer and unreacted comonomer from said solids, and
b. a recycle system comprising a vapour/liquid separator for recycling at least a portion of the unreacted monomer and unreacted comonomer,

said separator to which the fresh feed is passed being the “vapour/liquid separator” of step 3(b).

35 . A process according to claim 29 wherein the polymerisation reactor has a volume of at least 50 m 3 .

36 . A process according to claim 34 wherein the polymerisation reactor has a volume of at least 50 m 3 .

Assignees

• Ineos Europe Ag

Inventors

• Marissal Daniel
• Van Breuseghem Philip
• Walworth Brent R

Classifications

• C08F210/16 Primary

  Copolymers of ethene with alpha-alkenes, e.g. EP rubbers · CPC title

• C08F2/14 Primary

  Organic medium · CPC title

• C08F10/02

  Ethene · CPC title

• C08F2/06

  Organic solvent · CPC title

• C08F2/01

  characterised by special features of the polymerisation apparatus used · CPC title