CO2 recovery from IGCC power plants

• US 20090235822A1
• Filed: 03/18/2008
• Published: 09/24/2009
• Est. Priority Date: 03/18/2008
• Status: Active Grant

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: Joshi, Chetan Madhav, Maruthamuthu, Jegadeesan, Anand, Ashok Kumar
• Granted Patent: US 8,252,091 B2
• Time in Patent Office: Days
• US Class Current: 96/181
• CPC Class Codes: B01D 53/1475 Removing carbon dioxide
• CPC Class Codes: C10K 1/26 Regeneration of the purifying material contains also apparatus for the regeneration of the purifying material
• CPC Class Codes: Y02C 20/40 of CO2
• CPC Class Codes: Y02P 20/151 Reduction of greenhouse gas [GHG] emissions, e.g. CO2

Abstract

In a system involving CO₂ capture having an acid gas removal system to selectively remove CO₂ from shifted syngas, the acid gas removal system including at least one stage, e.g. a flash tank, for CO₂ removal from an input stream of dissolved carbon dioxide in physical solvent, the method of recovering CO₂ in the acid gas removal system including: elevating a pressure of the stream of dissolved carbon dioxide in physical solvent; and elevating the temperature of the pressurized stream upstream of at least one CO₂ removal stage.

Claims

1. In a system involving CO₂ capture having an acid gas removal system to selectively remove CO₂ from shifted syngas, the acid gas removal system including:

at least one stage for CO₂ removal from an input stream of dissolved carbon dioxide in physical solvent;

a pump for elevating a pressure of the stream of dissolved carbon dioxide in physical solvent to produce a pressurized stream; and

a heat exchanger for elevating the temperature of the pressurized stream upstream of at least one said CO₂ removal stage.

2. The system of claim 1, wherein said pump comprises a centrifugal pump.

3. The system of claim 1, wherein said heat exchanger is operatively coupled to at least one low-grade energy source for heating the pressurized stream.

4. The system of claim 3, wherein one of said low grade sources comprises lean physical solvent recovered in said acid gas removal system.

5. The system of claim 1, wherein said at least one CO₂ removal stage comprises a flash tank for deabsorbing captured CO₂ from said input stream of dissolved carbon dioxide in physical solvent.

6. The system of claim 1, wherein the acid gas removal system includes a plurality of stages of flash tanks for deabsorbing captured CO₂ from the input stream of dissolved carbon dioxide in physical solvent.

7. The system of claim 6, wherein a pump for elevating the pressure of the solvent stream and a heat exchanger for elevating the temperature of the solvent stream are disposed upstream of each said flash tank.

8. The system of claim 6, wherein there are three stages of flash tanks.

9. The system of claim 1, wherein a heat exchanger for reducing the temperature of the recovered CO₂ is disposed downstream of at least one said CO₂ removal stage.

10. The system of claim 7, wherein there are three stages of flash tanks for CO₂ removal, and a heat exchanger for reducing the temperature of the recovered CO₂ is disposed downstream of the second and third stage flash tanks.

11. The system of claim 1, wherein recovered CO₂ is compressed downstream of at least one said CO₂ removal stage.

12. In a system involving CO₂ capture having an acid gas removal system to selectively remove CO₂ from shifted syngas, the acid gas removal system including at least one stage for CO₂ removal from an input stream of dissolved carbon dioxide in physical solvent, the method of recovering CO₂ in the acid gas removal system including:

elevating a pressure of the stream of dissolved carbon dioxide in physical solvent to produce a pressurized stream; and

elevating the temperature of the pressurized stream upstream of at least one said CO₂ removal stage.

13. The method of claim 12, wherein said elevating a pressure comprises feeding the stream through a centrifugal pump.

14. The method of claim 12, wherein said elevating the temperature of the pressurized stream comprises feeding the solvent stream through a heat exchanger.

15. The method of claim 14, wherein said heat exchanger is operatively coupled to at least one low-grade energy source for heating the pressurized stream.

16. The method of claim 15, wherein one of said low grade sources comprises lean physical solvent recovered in said acid gas removal system.

17. The method of claim 12, wherein there are a plurality of CO₂ removal stages and the solvent stream is elevated in pressure and elevated in temperature upstream of each said CO₂ removal stage.

18. The method of claim 12, further comprising reducing the temperature of the recovered CO₂ downstream of at least one said CO₂ removal stage.

19. The method of claim 18, wherein there are three stages of flash tanks for CO₂ removal, and a heat exchanger for reducing the temperature of the recovered CO₂ is disposed downstream of the second and third stage flash tanks.

20. The method of claim 12, wherein recovered CO₂ is compressed downstream of at least one said CO₂ removal stage.