Annular divided wall column for an air separation unit

Patent metadata

Field	Value
Publication number	US-10578355-B2
Application number	US-201816042262-A
Country	US
Kind code	B2
Filing date	Jul 23, 2018
Priority date	Aug 25, 2017
Publication date	Mar 3, 2020
Grant date	Mar 3, 2020

Abstract

An annular divided wall column for the cryogenic rectification of air or constituents of air is provided. The annular divided wall column includes a first annular column wall and a second annular column wall disposed within the first annular column wall to define an annulus column region and an interior core column region. The present annular divided wall column further includes structured packing elements disposed within at least the annulus column region as well as a ring-shaped cantilevered collector; and a ring-shaped distributor disposed in the annulus column region above or below the plurality of structured packing elements. The thermal expansion and contraction of the second annular column wall in a radial direction and in an axial direction is independent of the thermal expansion and contraction of the first annular column wall in the radial and axial directions.

First claim

We claim:

1. An annular divided wall column for cryogenic rectification of air or constituents of air, said column comprising:
a first annular column wall;
a second annular column wall radially spaced from the first annular column wall and disposed within a first interior space of the first annular column wall to define an annulus column region between the first annular column wall and the second annular column wall and to define an interior core column region as part or all of a second interior space of the second annular column wall;
a conical shaped transition wall connected to the second annular column wall proximate a top end of the second annular column wall and further connected to the first annular column wall and configured to isolate the annulus column region from the interior core column region proximate the top end of the second annular column wall;
a plurality of structured packing elements of a first type or trays disposed within the interior core column region; and
a plurality of structured packing elements of a second type disposed within the annulus column region;
wherein the conical shaped transition wall is either: (i) fixedly attached to the second annular column wall proximate the top end of the second annular column wall and moveably hung on the first annular column wall; or (ii) moveably connected to the second annular column wall proximate the top end of the second annular column wall and fixedly connected to the first annular column wall; and
wherein thermal expansion and contraction of the second annular column wall in a radial direction and in an axial direction is independent of the thermal expansion and contraction of the first annular column wall in the radial direction and in the axial direction.

2. The annular divided wall column of claim 1 , wherein a vertical height of the first annular column wall is greater than a vertical height of the second annular column wall.

3. The annular divided wall column of claim 1 , wherein the annulus column region is configured for rectification of an argon-oxygen containing stream to separate it into an argon-rich overhead stream and an oxygen-rich stream.

4. The annular divided wall column of claim 1 , wherein the annulus column region is configured for rectification of a nitrogen-oxygen containing stream to separate it into a nitrogen rich overhead stream and an oxygen-rich stream.

5. The annular divided wall column of claim 1 , wherein the interior core column region is configured for rectification of an argon-oxygen containing stream to separate it into an argon-rich overhead stream and an oxygen-rich stream.

6. The annular divided wall column of claim 1 , wherein the interior core column region is configured for rectification of a nitrogen-oxygen containing stream to separate it into a nitrogen rich overhead stream and an oxygen-rich stream.

7. The annular divided wall column of claim 1 , wherein the annulus column region is configured for rectification of a nitrogen-oxygen containing stream to separate it into a first nitrogen rich overhead stream and a first oxygen-rich stream of a first purity and the interior core column region is configured for rectification of the nitrogen-oxygen containing stream to separate it into a second nitrogen rich overhead stream and a second oxygen-rich stream of a second purity.

8. The annular divided wall column of claim 1 , wherein the annulus column region is configured for rectification of a nitrogen-oxygen containing stream to separate it into a first nitrogen rich overhead stream of a first purity and a first oxygen-rich stream and the interior core column region is configured for rectification of the nitrogen-oxygen containing stream to separate it into a second nitrogen rich overhead stream of a second purity and a second oxygen-rich stream.

9. The annular divided wall column of claim 1 , wherein the plurality of structured packing elements are constructed of materials selected from a group consisting of: aluminum sheet metal, stainless steel sheet metal, stainless steel gauze, silicon carbide; and plastic.

10. The annular divided wall column of claim 1 , wherein the plurality of structured packing elements of a first type are disposed within the annulus column region and the plurality of structured packing elements of a second type are disposed within the interior core column region;
wherein the first type of structured packing elements and the second type of structured packing elements have different surface area densities.

11. The annular divided wall column of claim 10 , wherein the plurality of structured packing elements of the first type and of the second type have a surface area density between about 100 m 2 /m 3 to 1200 m 2 /m 3 .

12. The annular divided wall column of claim 1 , wherein the plurality of structured packing elements of a first type are disposed within the annulus column region and the plurality of structured packing elements of a second type are disposed within the interior core column region;
wherein the first type of structured packing elements and the second type of structured packing elements have different geometries.

13. The annular divided wall column of claim 12 , wherein the plurality of structured packing elements have a geometry that includes a nominal inclination angle of corrugations to the horizontal axis of between about 35° to 70°.

14. The annular divided wall column of claim 1 , wherein the plurality of structured packing elements are configured as rectangular bricks or arcuate shaped wedges.

Assignees

• Saboda Kevin J
• Belanger Paul W
• Lenz Richard D
• Larson Kirk F
• Brown Steven C
• Ricotta John P
• Chen Guang X
• Faust Jeremy D
• Praxair Technology Inc

Inventors

• Saboda Kevin J
• Belanger Paul W
• Lenz Richard D
• Larson Kirk F
• Brown Steven C
• Ricotta John P
• Chen Guang X
• Faust Jeremy D

Classifications

• F25J3/04903

  Plates or trays · CPC title

• F25J3/04921

  within the same column · CPC title

• B01D3/328

  Sealing between the column and the trays · CPC title

• F25J3/04084

  of nitrogen · CPC title

• B01J2219/30203

  Saddle · CPC title