Polymerization reaction system

• US 8,586,685 B2
• Filed: 07/20/2010
• Issued: 11/19/2013
• Est. Priority Date: 07/23/2009
• Status: Expired due to Fees

• Current Assignee: Univation Technologies LLC (Dow, Inc.)
• Original Assignee: Univation Technologies LLC (Dow, Inc.)
• Inventors: Hussein, F. David, Muhle, Michael E., Cai, Ping, Blood, Mark W.
• Primary Examiner(s): Teskin, Fred M
• Application Number:
  US13/377,205
• Publication Number:
  US 20120136127A1
• Time in Patent Office: 1,218 Days
• Field of Search: 526/67, 526/68, 526/918, 526/70, 422/131, 422/132, 422/134
• US Class Current: 526/70
• CPC Class Codes: B01J 2208/00256 in a heat exchanger for the heat exchange medium separate from the reactor
• CPC Class Codes: B01J 2208/00274 involving reactant vapours
• CPC Class Codes: B01J 2208/00283 involving reactant liquids
• CPC Class Codes: B01J 2208/00734 Controlling static charge
• CPC Class Codes: B01J 2219/0025 Foam formation
• CPC Class Codes: B01J 2219/00254 Formation of unwanted polymer, such as "pop-corn"
• CPC Class Codes: B01J 8/22 gas being introduced into the liquid
• CPC Class Codes: C08F 10/02 Ethene
• CPC Class Codes: C08F 110/02 Ethene
• CPC Class Codes: C08F 2/01 characterised by special features of the polymerisation apparatus used
• CPC Class Codes: C08F 2/14 Organic medium
• CPC Class Codes: C08F 2/34 Polymerisation in gaseous state
• CPC Class Codes: C08F 210/14 Monomers containing five or more carbon atoms
• CPC Class Codes: C08F 210/16 Copolymers of ethene with alpha-alkenes, e.g. EP rubbers
• CPC Class Codes: C08F 2500/24 Polymer with special particle form or size

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.

Claims

1. A process for the polymerization of olefins, comprising:

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 introduction zone at a rate sufficient to agitate the solid and liquid phases within the three-phase reaction zone;

withdrawing a reaction mixture comprising polyolefin and diluents from the three-phase reaction zone.

2. The process of claim 1, further comprising separating the withdrawn reaction mixture into a diluents liquid phase fraction and a polyolefin solid phase fraction.

3. The process of claim 1, further comprising reducing a temperature of the circulating gas phase composition via indirect heat exchange.

4. The process of claim 1, further comprising introducing at least one of a co-catalyst, an activator, an antistatic agent, an anti-foaming agent, a chain transfer agent, a comonomer, and make-up diluent to at least one of the polymerization vessel and the gas circulation loop.

5. The process of claim 1, wherein the catalyst is fed to the three-phase reaction zone of the polymerization vessel and wherein the olefin is indirectly fed to the polymerization vessel via the gas circulation loop.

6. The process of claim 1, wherein the withdrawn gas phase composition comprises diluent and olefin, the process further comprising:

condensing at least a portion of the diluent in an overheads condenser; and

recycling at least a portion of the condensed diluent to the three-phase reaction zone.

7. The process of claim 6, further comprising recycling at least a portion of the diluents liquid phase fraction to at least one of the three-phase reaction zone and the overheads condenser.

8. The process of claim 1, further comprising recycling at least a portion of the diluents liquid phase fraction to the three-phase reaction zone.

9. The process of claim 1, wherein the withdrawn gas phase composition comprises at least one of entrained liquids and entrained solids.

10. The process of claim 9, further comprising separating the at least one of entrained liquids and entrained solids from the gas phase composition.

11. The process of claim 1, the polymerization vessel comprising two or more three-phase reaction zones, two or more vapor introduction zones, and two or more vapor disengagement zones, where each of the two or more three-phase reaction zones are in fluid communication with an associated vapor introduction zone and an associated vapor disengagement zone.

12. The process of claim 11, further comprising:

withdrawing a gas phase composition from an outlet in fluid communication with each associated vapor disengagement zone; and

individually circulating the withdrawn gas phase compositions through a gas circulation loop to an inlet in fluid communication with the associated vapor introduction zone at a rate sufficient to agitate the solid and liquid phases within the three-phase reaction zone.

13. The process of claim 12, further comprising transporting a reaction mixture comprising polyolefin and diluents from one of the two or more three-phase reaction zones to another of the two or more three-phase reaction zones.

14. The process of claim 11, wherein the withdrawing a gas phase composition is from an outlet in fluid communication with an uppermost vapor disengagement zone, and wherein the circulating the gas phase composition is to an inlet of a lowermost vapor distribution zone.

15. The process of claim 1, further comprising operating the three-phase reaction zone at a boiling point of the liquid diluent to thereby maintain the three-phase reaction zone at substantially isothermal conditions.

16. The process of claim 1, wherein the olefin comprises at least one of ethylene and propylene.

17. The process of claim 16, wherein the olefin further comprises a polymerizable macromer.

18. A continuous three-phase polymerization reaction system, comprising:

a polymerization vessel having, from a polymerization vessel bottom to a polymerization vessel top, a vapor introduction zone, a three-phase reaction zone for a polymerization reaction in a liquid-continuous medium, and a vapor disengagement zone;

a gas circulation loop for circulating a gas phase composition from an outlet in fluid communication with the vapor disengagement zone to an inlet in fluid communication with the vapor introduction zone at a rate sufficient to agitate solids and liquids within the three-phase reaction zone;

a fluid inlet for introducing a polymerization catalyst to the three-phase reaction zone;

a fluid inlet for introducing an olefin to the reactor to form a solid phase polyolefin via contact with the polymerization catalyst;

a fluid outlet for withdrawing a reaction mixture comprising polyolefin and diluents from the three-phase reaction zone; and

a separation device for separating entrained liquids from the gas phase composition withdrawn from the vapor disengagement zone.

19. The reaction system of claim 18, further comprising a separator for separating the withdrawn reaction mixture into a diluents fraction and a polyolefin fraction.

20. The reaction system of claim 18, further comprising a circulating device for transporting at least a portion of the gas phase composition through the gas circulation loop.

21. The reaction system of claim 18, further comprising at least one heat exchanger to recover heat from the circulating gas phase composition.

22. The reaction system of claim 18, further comprising one or more fluid conduits for introducing at least one of a co-catalyst, an anti-foaming agent, an activator, an antistatic agent, a chain transfer agent, a comonomer, and liquid diluent to at least one of the polymerization vessel and the circulation loop.

23. The reaction system of claim 18, further comprising:

an overheads condenser system for reducing a temperature of the circulating gas phase composition via indirect heat exchange to condense at least a portion of the diluents; and

a fluid conduit for recycling at least a portion of the condensed diluents to the three-phase reaction zone.

24. The reaction system of claim 23, further comprising a fluid conduit for recycling at least a portion of the diluents fraction to at least one of the three-phase reaction zone and the overheads condenser.

25. The reaction system of claim 18, further comprising a separation device for separating entrained liquids and entrained solids from the gas phase composition withdrawn from the vapor disengagement zone.

26. The reaction system of claim 18, the polymerization vessel comprising two or more three-phase reaction zones, two or more vapor introduction zones, and two or more vapor disengagement zones, where each of the two or more three-phase reaction zones are in fluid communication with an associated vapor introduction zone and an associated vapor disengagement zone.

27. The reaction system of claim 26, further comprising two or more gas circulation loops for circulating a gas phase composition from an outlet in fluid communication with a vapor disengagement to an inlet in fluid communication with the associated vapor introduction zone at a rate sufficient to agitate solids and liquids within the associated three-phase reaction zone.

28. The reaction system of claim 27, further comprising a fluid conduit for transporting a reaction mixture comprising polyolefin and diluents from one of the two or more three-phase reaction zones to another of the two or more three-phase reaction zones.

29. The reaction system of claim 26, comprising a single gas circulation loop for circulating the gas phase composition from an outlet in fluid communication with an uppermost vapor disengagement zone to an inlet of a lowermost vapor introduction zone.

30. A polymerization reaction system comprising two or more reaction systems as defined in claim 18 configured for at least one of parallel and series operation.