Catalyst arrangement

Patent metadata

Field	Value
Publication number	US-9975767-B2
Application number	US-201515117673-A
Country	US
Kind code	B2
Filing date	Feb 17, 2015
Priority date	Mar 4, 2014
Publication date	May 22, 2018
Grant date	May 22, 2018

Abstract

A catalyst arrangement disposed within a vertical reaction tube includes a structured catalyst within an upper part of the reaction tube, a particulate catalyst beneath the structured catalyst in a lower part of the reaction tube, and a catalyst support device located between the structured catalyst and the particulate catalyst, wherein the catalyst support device includes a cylindrical body having a first end adapted for connection to the structured catalyst, and a second end, and the cylindrical body has a diameter 70-90% of the internal diameter of the tube and a length/diameter in the range 0.5-2.5.

First claim

The invention claimed is:

1. A reactor system comprising a catalyst arrangement disposed within a vertical reaction tube, said arrangement comprising:
a structured catalyst ( 52 , 54 ) disposed within an upper part of the reaction tube,
a particulate catalyst ( 56 ) disposed beneath said structured catalyst in a lower part of said reaction tube, and
a catalyst support device ( 40 ) located between the structured catalyst and the particulate catalyst, wherein the catalyst support device comprises a cylindrical body ( 72 ) located centrally within the vertical reaction tube, the cylindrical body having a first end connected to the structured catalyst, and a second end ( 70 ), wherein the cylindrical body has a diameter of 70-90% of the internal diameter of the tube and a length/diameter in the range of 0.5-2.5.

2. The reactor system according to claim 1 wherein the structured catalyst comprises a catalyst supported on or contained within a structure.

3. The reactor system according to claim 1 wherein the first end comprises a rod, pin or other locating projection that matches an orifice in the structured catalyst.

4. The reactor system according to claim 1 wherein the catalyst support device has 2 or more peripheral lugs or tabs evenly spaced about the outer surface of the body to space the cylindrical body centrally within the tube.

5. The reactor system according to claim 4 wherein the lugs or tabs direct the flow of gas between the device and the inner wall of the tube.

6. The reactor system according to claim 1 wherein the outer surface of the cylinder includes one or more grooves to direct the flow of gas between the device and the inner wall of the tube vertically or at an angle to the central axis of the tube.

7. The reactor system according to claim 1 wherein the cylindrical body comprises a plurality of orifices in the first end leading to channels through the catalyst support device that open on the outer surface of the cylinder at one or more points along its length and/or the second end.

8. The reactor system according to claim 1 wherein cylindrical body includes a reservoir of the particulate catalyst.

9. The reactor system according to claim 8 wherein the second end of the cylinder comprises a thermally decomposable material that, before or during start-up of the reaction tube, decomposes by heating to provide an opening in the second end through which the particulate catalyst may pass.

10. The reactor system according to claim 9 wherein the second end of the cylindrical body is closed with a thin membrane that is polypropylene or cardboard.

11. The reactor system according to claim 8 wherein the length of the cylinder is at least 5 times the particle size of the particulate catalyst.

12. The reactor system according to claim 1 wherein the structured catalyst is free to move down the tube.

13. The reactor system according to claim 1 wherein the catalyst arrangement comprises a structured steam reforming catalyst and a particulate steam reforming catalyst and the vertical reaction tube is located within a catalytic steam reformer.

14. The reactor system according to claim 13 wherein the steam reformer is a top-fired steam reformer or a side-fired steam reformer, wherein the hot gas is provided by combusting a fuel gas using a plurality of burners disposed either at the top end or along the length of the tubes.

15. The reactor system according to claim 13 wherein the steam reformer is a gas-heated reformer (GHR) ,wherein the hot gas is provided by a flue-gas from a combustion process, generated by catalytic or non-catalytic partial oxidation of a hydrocarbon, or provided by autothermal reforming a hydrocarbon and/or the reformed gas mixture.

16. The reactor system according to claim 13 wherein the tubes have a circular cross section and a length in the range of 5 to 15 m and an internal diameter in the range of 5 to 30 cm.

17. The reactor system according to claim 13 wherein the particulate steam reforming catalyst is formed from a refractory support material impregnated with nickel, a precious metal, or mixtures thereof.

18. The reactor system according to claim 13 wherein the particulate steam reforming catalyst comprises cylindrical pellets with one or more through holes ( 46 ), with a diameter in the range of 3-50 mm and a length/diameter ratio in the range of 0.5-2.0.

19. The reactor system according to claim 13 wherein the structured steam reforming catalyst is a steam reforming catalyst supported on a structure.

20. The reactor system according to claim 19 wherein the structured steam reforming catalyst comprises metal or ceramic shaped units wash-coated with a layer of steam reforming catalyst.

21. The reactor system according to claim 19 wherein the structured catalyst is one or more cylindrical units with a diameter complimentary to the tubes in which they are placed that comprises perforations and/or folded leafs and/or tabs that cause process fluid to flow both axially and radially as it passes through the units.

22. The reactor system according to claim 13 wherein the structured steam reforming catalyst is a steam reforming catalyst contained within a structure.

23. The reactor system according to claim 22 wherein the structure in which the steam reforming catalyst is contained comprises discrete catalyst containers, cups or cans that include passages through which a process fluid passes in ordered, non-random directions.

24. The reactor system according to claim 22 wherein catalyst contained in the structure is a particle, catalysed metal, catalysed ceramic foam, catalyzed metal honeycomb structure, or catalysed ceramic honeycomb structure.

25. The reactor system according to claim 22 wherein the steam reforming catalyst comprises nickel, a precious metal, or a mixture thereof on a refractory oxide.

26. A process for performing a reaction in a vertical reaction tube comprising the steps of:
(i) passing a feed gas mixture through the reaction tube disposed within a reactor, and
(ii) recovering a reacted gas mixture from the reaction tube, wherein a catalyst arrangement is disposed within the reaction tube, said arrangement comprising:
a structured catalyst within an upper part of the reaction tube,
a particulate catalyst beneath said structured catalyst in a lower part of said reaction tube, and
a catalyst support device located between the structured catalyst and the particulate catalyst, wherein the catalyst support device comprises a cylindrical body located centrally within the tube, having a first end connected to the structured catalyst and a second end, wherein the cylindrical body has a diameter of 70-90% of the internal diameter of the tube and a length/diameter in the range of 0.5-2.5.

27. The process according to claim 26 , wherein:
the feed gas mixture comprises hydrocarbon and steam and is passed through a plurality of externally-heated vertical tubes disposed within a steam reformer,
the recovered reacted gas is a reformed gas mixture,
the structured catalyst is a structured steam reforming catalyst, and
the particulate catalyst is a particulate steam reforming catalyst.

28. The process according to claim 27 wherein the density-modified inlet mass rate of the mixture fed to the catalyst-coated structured packing is in the range of 5 to 30 kg/m 2 s.

Assignees

• Johnson Matthey Plc

Inventors

• Farnell Peter William

Classifications

• B01J2219/32279

  Tubes or cylinders · CPC title

• B01J2219/32408

  Metal · CPC title

• B01J2219/32244

  Essentially circular apertures · CPC title

• B01J2219/32237

  Sheets comprising apertures or perforations · CPC title

• B01J8/06 Primary

  in tube reactors; the solid particles being arranged in tubes · CPC title