Process and apparatus for endothermic reactions

Patent metadata

Field	Value
Publication number	US-9533275-B2
Application number	US-201314426027-A
Country	US
Kind code	B2
Filing date	Aug 14, 2013
Priority date	Sep 13, 2012
Publication date	Jan 3, 2017
Grant date	Jan 3, 2017

Abstract

A furnace for performing an endothermic process comprises tubes containing a catalyst for converting a gaseous feed, said tubes positioned inside the furnace, inner burners mounted to a furnace roof between the tubes, and outer burners mounted to the furnace roof between the tubes and a furnace wall. The outer burners are positioned close to the furnace wall, and configured to operate with 45-60% of the power of the inner burners and with an inlet velocity between 90 to 110% of the inlet velocity of the inner burners.

First claim

The invention claimed is:

1. A furnace for performing an endothermic process comprising tubes containing a catalyst for converting a gaseous feed, wherein said tubes are positioned in inside the furnace, inner burners mounted to a furnace roof between the tubes, and outer burners mounted to the furnace roof between the tubes and a furnace wall, wherein the outer burners are positioned such that the distance of the central axis of each outer burner to the furnace wall is less than 25% of the distance between the outermost tubes and the furnace wall, and that the outer burners are configured to operate with 45-60% of the power of the inner burners and with an inlet velocity between 90 to 110% of the inlet velocity of the inner burners.

2. The furnace according to claim 1 , wherein the tubes are positioned in rows and that the ratio of the distance between the furnace wall and the first tube row to the gap between two adjacent tube rows corresponds to the ratio between the power of the outer and the power of the inner burners.

3. The furnace according to claim 1 , wherein at least a part of the furnace roof is provided with a temperature resistant, high emissivity solid surface.

4. The furnace according to claim 3 , wherein the high emissivity solid surface contains silicon carbide or ceramic porous foams.

5. The furnace according to claim 1 , wherein at least some of the burners are jet flame burners.

6. The furnace according to claim 1 , wherein at least some of the burners are burners with high swirl ball flame technology.

7. The furnace according to claim 1 , wherein at least some of the burners are arranged such that the flame is formed on a porous radiating shield.

8. The furnace according to claim 7 , wherein at least some of the burners are arranged in a square or a hexahedral configuration with regard to the catalyst tubes.

9. The furnace according to claim 7 , wherein the length of radiating shield is between 10 and 40% of the catalyst containing tube length.

10. The furnace according to claim 1 , wherein at least a part of the furnace roof is designed to have a convex or concave shape.

11. A process for operating a furnace for performing an endothermic process with catalyst containing tubes positioned in inside the furnace for converting a gaseous feed and which are heated by inner burners mounted to a furnace roof between the tubes and by outer burners mounted to the furnace roof between the tubes and a furnace wall, wherein the outer burners are positioned such that the distance of the central axis of each outer burner to the furnace wall is less than 25% of the distance between the outermost tubes and the furnace wall, and that the outer burners are operated with 45-60% of the power of the inner burners and that an inlet velocity of the outer burners is adjusted to be between 90 and 110% of the inlet velocity of the inner burners.

12. The process according to claim 11 , wherein at least some of the burners' flames are directed from the top to the bottom of the furnace.

13. The process according to claim 11 , wherein the feed flows through the vertically arranged catalyst tubes from the top to the bottom of the furnace.

14. The process according to claim 11 , wherein the inlet velocity is adjusted by air injection.

15. The process according to claim 11 , wherein the endothermic process is a steam reforming process.

Assignees

• L'Air Liquide Société Anonyme pour l'Etude et l'Exploitation des Procédés Georges Claude
• L'Air Liquide Société Anonyme Pour L'Étude Et L'Exploitation Des Procedes Georges Claude

Inventors

• Cances Julien
• Camy-Peyret Frederic
• Labegorre Bernard

Classifications

• C01B2203/0233

  the reforming step being a steam reforming step · CPC title

• C01B3/384 Primary

  with external heating of the catalyst · CPC title

• C01B2203/0816

  Heating by flames · CPC title

• F27D7/02

  Supplying steam, vapour, gases or liquids · CPC title

• F23C13/00

  Apparatus in which combustion takes place in the presence of catalytic material (in a fluidised bed of catalytic particles F23C10/01; radiant gas burners using catalysis for flameless combustion F23D14/18) · CPC title