Devolatilisation apparatus and a process for use thereof

Patent metadata

Field	Value
Publication number	US-10143941-B2
Application number	US-201414763707-A
Country	US
Kind code	B2
Filing date	Feb 3, 2014
Priority date	Feb 28, 2013
Publication date	Dec 4, 2018
Grant date	Dec 4, 2018

Abstract

A static devolatilisation apparatus ( 1 ) adapted for devolatilising a viscous liquid ( 2 ) comprising a volatile component is disclosed. The apparatus ( 1 ) comprises a phase separation chamber ( 100 ) in an upper region ( 5 ) for treating the viscous liquid ( 2 ) in a first devolatilisation step to form a first devolatilised viscous liquid ( 21 ), and a distributor sub-unit 200 is located below the phase separation chamber ( 100 ) and above a lower sump region ( 4 ). The sub-unit ( 200 ) has a second discharge region ( 222 ) embodied such that it is contacted by the first devolatilised viscous liquid ( 21 ), and the region ( 222 ) has a surface ( 223 ) embodied such that the first devolatilised viscous liquid ( 21 ) is treated in a second devolatilisation step. The present invention further relates to a process to devolatilising a viscous liquid using the apparatus ( 1 ) and also to the use of the apparatus ( 1 ) in the devolatilisation of polymer melt or solution.

First claim

The invention claimed is:

1. A static devolatilisation apparatus for devolatilising a viscous liquid comprising a volatile component, wherein the apparatus comprises:
a container for receiving a first devolatilised viscous liquid, said container having a lower sump region for collecting a second devolatilised viscous liquid, an upper region for discharging a gas, and a central region between said lower sump region and said upper region;
a discharge pump in fluid communication with said lower sump region for discharging the second devolatilised viscous liquid therefrom;
an extraction line for discharging gas from the container; and
a phase separation chamber in said upper region of said container, wherein the phase separation chamber comprises an inlet for the viscous liquid to be treated in a first devolatilisation step to form a first devolatilised viscous liquid, a plurality of first discharge openings in a lower portion of a first discharge region for discharging said first devolatilised viscous liquid downwardly towards said lower sump region and at least one gas discharge opening in an upper portion of said first discharge region for discharging gas upwardly to said extraction line,
wherein a valve is in fluid communication with the inlet of the phase separation chamber,
wherein a distributor sub-unit is located in said central region and below the phase separation chamber and above the lower sump region, wherein the distributor sub-unit has a second discharge region, wherein a minimum distance between the first discharge region and the second discharge region is at least 1.5 times the diameter of the phase separation chamber, and
wherein the second discharge region is embodied such that it is contacted by the first devolatilised viscous liquid discharged from the first discharge openings of the phase separation chamber, and wherein the second discharge region has a surface embodied such that the first devolatilised viscous liquid is treated in a second devolatilisation step on said surface to form a second devolatilised viscous liquid, and wherein the second discharge region additionally has a plurality of second discharge openings in fluid communication with the discharge pump and for the discharge of said second devolatilised viscous liquid.

2. The apparatus of claim 1 , wherein the distributor sub-unit has a third discharge region embodied such that it is not contacted by the first devolatilised viscous liquid discharged by the first discharge openings of the phase separation chamber.

3. The apparatus of claim 2 , wherein the lower portion of the first discharge region has a first cross-sectional area that is less than a second cross-sectional area of the second discharge region.

4. The apparatus of claim 2 , wherein the discharge region has third discharge openings for discharge of a gas.

5. The apparatus of claim 1 , wherein there is a gap present between the distributor sub-unit and an inner wall of the container.

6. The apparatus of claim 1 , wherein the second discharge openings are embodied such that the openings have cross-sectional areas that increase as the openings are progressively located towards an outer perimeter of the second discharge region.

7. The apparatus of claim 1 , wherein the apparatus additionally comprises one to four further distributor sub-units.

8. The apparatus of claim 7 , wherein the surface(s) of the second discharge region(s) of the distributor sub-unit(s) are embodied such that the surfaces(s) of the second discharge region(s) increase a residence time of the first devolatilised viscous liquid in the container and/or a specific surface area of the first devolatilised viscous liquid dispersed over the surface(s) of the second discharge region(s).

9. The apparatus of claim 7 , wherein the distributor sub-unit(s) have shape(s) that are selected from plates, trays, or cones.

10. The apparatus of claim 1 , wherein moving parts are absent within the container.

11. The apparatus of claim 1 , wherein the inlet of the phase separation chamber is located in the lower sump region.

12. The apparatus of claim 11 , wherein the apparatus has an inlet for the dosing of a stripping agent.

13. A process for devolatilising a viscous liquid comprising a volatile component using the apparatus of claim 1 , wherein the process comprises:
a first devolatilisation step in which the viscous liquid is treated in a phase separation chamber to form a first devolatilised viscous liquid, and
a second devolatilisation step in which the first devolatilised viscous liquid is treated in a distributor sub-unit having a second discharge region to form a second devolatilised viscous liquid, whereby the second discharge region has a surface embodied such that the second devolatilisation step takes place on said surface and a residence time of the first devolatilised viscous liquid in the container and/or a specific surface of the first devolatilised viscous liquid dispersed over the surface is thereby increased.

14. The process of claim 13 , wherein the viscous liquid is a polymer melt or polymer solution and the volatile component is a solvent or a monomer.

15. The process of claim 13 , wherein a stripping agent is dosed to the viscous liquid before the first devolatilisation step and/or dosed in the container by means of an inlet.

16. The process of claim 15 , wherein the inlet is located in the lower sump region.

17. A method for devolatilising a viscous liquid comprising steps of providing the apparatus of claim 15 and using the apparatus of claim 15 in the devolatilisation of viscous liquid, thereby devolatilising the viscous liquid.

18. The method of claim 17 , wherein the viscous liquid is a polymer melt or polymer solution, comprising a volatile component.

Assignees

• Sulzer Chemtech Ag

Inventors

• Loviat François

Classifications

• B01J4/001

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

• B01D3/009

  in combination with chemical reactions · CPC title

• C08F6/003

  from polymer solutions, suspensions, dispersions or emulsions without recovery of the polymer therefrom · CPC title

• B29B13/00

  Conditioning or physical treatment of the material to be shaped (chemical aspects C08J3/00 {; heating, cooling or curing during shaping B29C35/00; thermal after-treatment B29C71/02}) · CPC title

• B01D19/0042

  modifying the liquid flow (B01D19/0021 takes precedence) · CPC title