CO 2 recovery from IGCC power plants

• US 8,252,091 B2
• Filed: 03/18/2008
• Issued: 08/28/2012
• Est. Priority Date: 03/18/2008
• Status: Expired due to Fees

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: Anand, Ashok Kumar, Joshi, Chetan Madhav, Maruthamuthu, Jegadeesan
• Primary Examiner(s): Smith, Duane
• Application Number:
  US12/076,386
• Publication Number:
  US 20090235822A1
• Time in Patent Office: 1,624 Days
• Field of Search: 961/95, 952/61, 951/72, 951/77, 951/92, 952/08, 952/36
• US Class Current: 95/172
• 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 consisting of substantially only dissolved carbon dioxide in physical solvent, the method of recovering CO₂ in the acid gas removal system including:

elevating a pressure of said input stream of dissolved carbon dioxide in physical solvent to produce a pressurized stream upstream of said at least one CO₂ removal stage; and

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

2. The method of claim 1, wherein said elevating a pressure comprises feeding the stream through a centrifugal pump.

3. The method of claim 1, wherein said elevating the temperature of the pressurized stream comprises feeding the solvent stream through a heat exchanger.

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

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

6. The method of claim 1, 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.

7. The method of claim 1, further comprising reducing the temperature of the recovered CO₂ downstream of at least one said CO₂ removal stage.

8. The method 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.

9. The method of claim 1, wherein recovered CO₂ is compressed downstream of at least one said CO₂ removal stage in preparation for storage and sequestration.