RSC external downcomer tube arrangement

Patent metadata

Field	Value
Publication number	US-10234210-B2
Application number	US-201615246355-A
Country	US
Kind code	B2
Filing date	Aug 24, 2016
Priority date	Aug 24, 2016
Publication date	Mar 19, 2019
Grant date	Mar 19, 2019

Abstract

A system includes a radiant syngas cooler which receives and cools syngas generated in a gasifier. The radiant syngas cooler includes an outer shell of the radiant syngas cooler defining an annular space of the radiant syngas cooler and a heat exchange tube of the radiant syngas cooler positioned within the annular space and configured to flow a cooling medium. The heat exchange tube is configured to enable heat exchange between the syngas and the cooling medium to cool the syngas. The radiant syngas cooler includes a downcomer tube of the radiant syngas cooler which supplies the cooling medium to the heat exchange tube, where the downcomer tube includes a downflow portion positioned outside of the annular space of the radiant syngas cooler. The downflow portion is fluidly coupled to a header, and the header fluidly couples the downcomer tube to the heat exchange tube.

First claim

The invention claimed is:

1. A system, comprising:
a radiant syngas cooler configured to receive and cool syngas generated in a gasifier;
an outer shell of the radiant syngas cooler defining an annular space of the radiant syngas cooler;
a heat exchange tube of the radiant syngas cooler positioned within the annular space and configured to flow a cooling medium, wherein the heat exchange tube is configured to enable heat exchange between the syngas and the cooling medium to cool the syngas; and
a downcomer tube of the radiant syngas cooler configured to supply the cooling medium to the heat exchange tube, wherein the downcomer tube comprises a downflow portion positioned outside of the outer shell of the radiant syngas cooler, wherein the downflow portion of the downcomer tube extends axially along a length of the outer shell of the radiant syngas cooler at least to a bottom portion of the outer shell, such that the downflow portion is fluidly coupled to a header, and the header fluidly couples the downcomer tube to the heat exchange tube.

2. The system of claim 1 , wherein the downcomer tube comprises a first downcomer branch tube and a second downcomer branch tube, wherein the first downcomer branch tube fluidly couples the downcomer tube to the header, and the second downcomer branch tube fluidly couples the downcomer tube to an additional header.

3. The system of claim 2 , wherein the header is a platen tube header fluidly coupling the first downcomer branch tube to a plurality of platen tubes configured to flow the cooling medium, and the additional header is a cage tube header fluidly coupling the second downcomer branch tube to a plurality of cage tubes configured to flow the cooling medium.

4. The system of claim 3 , wherein the plurality of cage tubes surround the plurality of platen tubes, and the radiant syngas cooler comprises additional platen headers fluidly coupling additional pluralities of platen tubes to additional downcomer tubes, wherein the additional downcomer tubes each have respective downflow portions positioned outside of the annular space of the radiant syngas cooler.

5. The system of claim 3 , wherein the downcomer tube comprises a crossflow portion extending from the downflow portion and into the annular space of the radiant syngas cooler, wherein the crossflow portion extends through an opening in the plurality of cage tubes.

6. The system of claim 5 , wherein the plurality of cage tubes have a bent portion accommodating a receptacle for the downcomer tube.

7. The system of claim 3 , wherein the downcomer tube comprises a third downcomer branch tube fluidly coupling the downcomer tube to an additional platen tube header, the additional platen tube header being fluidly coupled to an additional plurality of platen tubes.

8. The system of claim 2 , wherein the first downcomer branch tube and the second downcomer branch tube extend in opposite directions from the downcomer tube.

9. The system of claim 2 , wherein the first downcomer branch tube and the second downcomer branch tube extend from a concentric reducer of the downcomer tube.

10. The system of claim 1 , wherein the downflow portion of the downcomer tube comprises an expansion joint configured to allow expansion and contraction resulting from thermal fluctuations.

11. The system of claim 1 , wherein the downcomer tube comprises a downflow portion and a crossflow portion extending from the downflow portion and into the annular space of the radiant syngas cooler, wherein a region of the crossflow portion positioned within the annular space is constructed from one or more materials capable of withstanding higher temperatures compared to materials of the downflow portion.

12. The system of claim 1 , wherein the downcomer tube comprises a bleed line positioned outside of the outer shell of the radiant syngas cooler.

13. The system of claim 1 , wherein the downcomer tube is a first downcomer tube, and the radiant syngas cooler comprises a second downcomer tube, wherein the first and second downcomer tubes comprise a first downcomer branch tube and a second downcomer branch tube, respectively, wherein the first downcomer branch tube fluidly couples the first downcomer tube to a first platen tube header, the second downcomer branch tube fluidly couples the second downcomer tube to a second platen tube header separate from the first, and the first and second downcomer branch tubes overlap one another.

14. The system of claim 13 , wherein the first downcomer branch tube comprises a bend that allows the second downcomer branch tube to access the second platen tube header.

15. A system, comprising:
a radiant syngas cooler comprising a plurality of platen tubes extending from one or more platen tube headers within an annular space of the radiant syngas cooler and a plurality of downcomer tubes having vertical portions disposed circumferentially around an exterior of the radiant syngas cooler and horizontal portions extending into the annular space, wherein the horizontal portions comprise inner portions disposed within the annular space and outer portions disposed outside of the annular space;
a first plurality of elbow joints coupled between the vertical portions and the outer portions of the plurality of the downcomer tubes;
a second plurality of elbow joints coupled to the internal portions and a plurality of concentric reducers coupled to the second plurality of elbow joints;
a plurality of downcomer branches extending from the concentric reducers, wherein at least a portion of the plurality of downcomer branches is coupled to the one or more platen tube headers; and
a cage bottom header disposed below the one or more platen tube headers, wherein at least one downcomer branch of the plurality of downcomer branches is coupled to the cage bottom header.

16. The system of claim 15 , wherein the first plurality of elbow joints, the vertical portions, and the outer portions each comprise carbon steel.

17. The system of claim 15 , wherein the concentric reducers, the second plurality of elbow joints, and the internal portions each comprise a superalloy.

18. The system of claim 15 , wherein the first plurality of elbow joints, the vertical portions, and the outer portions are each constructed from materials that are more heat resistant than materials used to construct the first plurality of elbow joints, the vertical portions, and the outer portions.

19. The system of claim 15 , wherein a diameter of the downcomer tubes is about twice that a diameter of the plurality of downcomer branches.

20. A system, comprising:
a gasifier configured to generate a syngas fluidly coupled to a radiant syngas cooler;
the radiant syngas cooler comprising a plurality of platen tubes extending from one or more platen tube headers within the cooler and a plurality of downcomer tubes disposed circumferentially around the cooler, wherein the plurality of platen tubes are configured to cool a syngas flowing through the cooler;
a first plurality of elbow joints coupled between a vertical portion of the downcomer tube and a horizontal portion of the downcomer tube, wherein the elbow joints are configured to extend the horizontal portion of each downcomer tube in a radially inward direction relative to the cooler;
a cooler wall of the radiant syngas cooler, wherein the horizontal portion of each downcomer tube comprises an internal portion that is internal to the cooler wall and an external portion that is external to the cooler wall;
a second plurality of elbow joints coupl

Assignees

• Gen Electric

Inventors

• Karmakar Pallab
• Chen Lien-Yan
• Zhou Qiong

Classifications

• C01B2203/0415

  Purification by absorption in liquids · CPC title

• C10J3/82

  Gas withdrawal means · CPC title

• C01B2203/0283

  containing a CO-shift step, i.e. a water gas shift step · CPC title

• C10J2300/1603

  with gas treatment · CPC title

• C01B2203/0894

  Generation of steam · CPC title