Process for preparing polyolefins

Patent metadata

Field	Value
Publication number	US-8946359-B2
Application number	US-201113812693-A
Country	US
Kind code	B2
Filing date	Jul 29, 2011
Priority date	Jul 30, 2010
Publication date	Feb 3, 2015
Grant date	Feb 3, 2015

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.

First claim

The invention claimed is:

1. A process of preparing a polyolefin in a loop reactor in the presence of anti-fouling agent, said loop reactor comprising interconnected pipes, defining a reactor path, and an axial pump comprising a motor, a shaft and an impeller, characterized in that at least part of the anti-fouling agent is introduced into said loop reactor through a sleeve provided around at least part of the shaft of said axial pump.

2. The process according to claim 1 , wherein at least part of the anti-fouling agent is fed against a side of the impeller which is connected to the shaft of said axial pump.

3. The process according to claim 1 , wherein all anti-fouling agent is fed through the sleeve into the loop reactor.

4. The process according to claim 1 , wherein the anti-fouling agent is dissolved at a concentration of 0.1-10% by weight in a solvent.

5. The process according to claim 1 , wherein the anti-fouling agent is fed under flushing with diluent.

6. The process according to claim 5 , wherein the diluent comprises less than 15% by weight of monomer.

7. The process according to claim 1 , wherein said polyolefin is produced in slurry conditions.

8. The process according to claim 1 , wherein said loop reactor is a double loop reactor.

9. The process according to claim 8 , wherein the anti-fouling agent is introduced into a first loop reactor of the double loop reactor through the sleeve provided around at least part of the shaft of the axial pump of the first loop reactor.

10. The process according to claim 1 , wherein the polyolefin is polyethylene.

11. A process for using anti-fouling agent to prevent or reduce fouling of a loop reactor during a polymerization process comprising a pump with a shaft and an impeller comprising introducing the anti-fouling agent into the loop reactor against a side of the impeller which is connected to the shaft of said pump.

12. The process according to claim 11 , wherein at least part of the anti-fouling agent is introduced in the loop reactor through a sleeve provided around at least part of the shaft of said pump.

13. The process according to claim 12 , wherein all anti-fouling agent is fed through the sleeve into the loop reactor.

14. The process according to claim 11 , wherein the anti-fouling agent is dissolved at a concentration of 0.1-10% by weight in a solvent.

15. The process according to claim 1 , wherein the anti-fouling agent comprises cationic agents, anionic agents, nonionic agents, organometallic agents, polymeric agents or mixtures thereof.

16. The process according to claim 5 , wherein the diluent comprises less than 10% by weight of monomer.

17. The process according to claim 5 , wherein the diluent comprises less than 5% by weight of monomer.

18. The process according to claim 5 , wherein the diluent comprises less than 1% by weight of monomer.

Assignees

• Siraux Daniel
• Vantomme Aurélien
• Damme Eric
• Dewachter Daan
• Total Res & Technology Feluy

Inventors

• Siraux Daniel
• Vantomme Aurélien
• Damme Eric
• Dewachter Daan

Classifications

• B01J19/1818

  in series · CPC title

• C08F210/16

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

• C08F2/01 Primary

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

• B01J4/001 Primary

  Feed or outlet devices as such, e.g. feeding tubes · CPC title

• B01J8/007

  by sedimentation · CPC title