Methods and systems for reducing carbon dioxide in combustion flue gases

• US 8,398,743 B2
• Filed: 05/08/2007
• Issued: 03/19/2013
• Est. Priority Date: 05/08/2007
• Status: Expired due to Fees

• Current Assignee: BHA Altair LLC (Parker-Hannifin Corporation)
• Original Assignee: General Electric Company
• Inventors: Molaison, Jennifer Lynn, Smithies, Alan
• Primary Examiner(s): Hopkins, Robert A
• Application Number:
  US11/801,043
• Publication Number:
  US 20080276803A1
• Time in Patent Office: 2,142 Days
• Field of Search: 95/45, 95/51, 95210-211, 951/83, 952/36, 96/4, 96/8, 962/34, 962/90, 962/74, 962/96
• US Class Current: 95/51
• CPC Class Codes: B01D 2251/2062 Ammonia
• CPC Class Codes: B01D 53/1475 Removing carbon dioxide
• CPC Class Codes: B01D 53/18 Absorbing units; Liquid distributors therefor B01D3/16, B01D3/26, B01D3/30 take precedence; packing elements B01J19/30, B01J19/32
• CPC Class Codes: B01D 53/62 Carbon oxides
• CPC Class Codes: B01D 61/00 Processes of separation using semi-permeable membranes, e.g. dialysis, osmosis or ultrafiltration; Apparatus, accessories or auxiliary operations specially adapted therefor separation of gases or vapours by diffusion B01D53/22
• CPC Class Codes: Y02A 50/20 Air quality improvement or preservation, e.g. vehicle emission control or emission reduction by using catalytic converters
• CPC Class Codes: Y02C 20/40 of CO2
• CPC Class Codes: Y02E 20/32 Direct CO2 mitigation

Abstract

A method for processing flue-gas, in an exemplary embodiment, includes providing an absorber unit having a membrane contactor, channeling a combustion flue gas along a first surface of the membrane contactor, and channeling an ammonia-based liquid reagent along a second opposing surface of the membrane contactor. The method also includes partially separating the ammonia-based liquid from the flue gas such that the ammonia-based liquid and the flue gas contact at gas-liquid interface areas, defined by a plurality of pores of the membrane contactor, to separate CO₂ from the flue gas by a chemical absorption of CO₂ within the ammonia-based liquid to produce a CO₂-rich ammonia-based liquid.

Claims

1. A method for processing flue-gas that contains carbon dioxide (CO₂), said method comprising:

providing an absorber unit having a membrane contactor that has a surface area of about 10 to about 100 m²/gr and a void volume of about 90% to about 95%;

channeling a combustion flue gas along a first surface of the membrane contactor;

channeling an ammonia-based liquid reagent along a second opposing surface of the membrane contactor;

coupling a desorber unit in flow communication with the absorber unit to receive carbon dioxide (CO₂)-laden ammonia-based liquid reagent from the absorber unit; and

channeling lean ammonia-based liquid reagent discharged from the desorber unit through a steam generator coupled in flow communication between the desorber unit and the absorber unit.

2. A method in accordance with claim 1 further comprising coupling a desorber unit to the absorber unit.

3. A method in accordance with claim 2 further comprising channeling the CO₂-rich ammonia-based liquid to the desorber unit.

4. A method in accordance with claim 3 further comprising heating the CO₂-rich ammonia-based liquid to release CO₂ from the CO₂-rich ammonia-based liquid.

5. A method in accordance with claim 1 wherein providing an absorber unit having a membrane contactor comprises providing an absorber unit having a hydrophobic membrane contactor.

6. A method in accordance with claim 1 wherein providing an absorber unit having a membrane contactor comprises providing an absorber unit having an expanded polytetrafluoroethylene membrane contactor.

7. A combustion system comprising:

an absorber unit comprising;

a housing for channeling a combustion flue gas that contains carbon dioxide (CO₂);

an ammonia-based liquid reagent channeled within said housing;

a membrane contactor positioned within said housing, wherein said membrane contactor comprises a first surface, a second opposing surface, and a plurality of pores defining gas-liquid interface areas and having a surface area of about 10 to about 100 m²/gr and a void volume of about 90% to about 95%, the combustion flue gas is channeled along said first surface and said ammonia-based liquid reagent is channeled along said second opposing surface; and

a desorber unit coupled to said absorber unit, wherein said desorber unit receives and releases CO₂ from the CO₂-rich ammonia-based liquid; and

a steam generator coupled between said desorber unit and said absorber unit, such that lean ammonia-based liquid reagent discharged from the desorber unit is channeled through said steam generator prior to entering said absorber unit.

8. A combustion system in accordance with claim 7 wherein said membrane contactor comprises a hydrophobic material.

9. A combustion system in accordance with claim 7 wherein said membrane contactor comprises an expanded polytetrafluoroethylene material.

10. A combustion system in accordance with claim 7 wherein said membrane contactor comprises a plurality of hollow fibers.

11. A combustion system in accordance with claim 10 wherein said plurality of hollow fibers is packaged in a tube-and-shell arrangement.

12. A combustion system in accordance with claim 7 wherein said membrane contactor comprises a substantially planar sheet.

13. A combustion system in accordance with claim 12 wherein said substantially planar sheet is packaged as a spiral-wound module.

14. A flue-gas processing system comprising:

a housing for channeling a combustion flue gas that contains carbon dioxide (CO₂);

an ammonia-based liquid reagent channeled within said housing; and

a membrane contactor positioned within said housing, wherein said membrane contactor comprises a first surface, a second opposing surface, and a plurality of pores defining gas-liquid interface areas, said membrane contactor having a surface area of about 10 to about 100 m²/gr and a void volume of about 90% to about 95%, the combustion flue gas is channeled along said first surface and said ammonia-based liquid reagent is channeled along said second opposing surface;

a desorber unit coupled to said housing for receiving carbon dioxide (CO2)-laden ammonia-based liquid reagent from said housing; and

a steam generator coupled in flow communication with said desorber unit, for receiving a lean ammonia-based liquid reagent discharged from said desorber unit and for channeling the lean ammonia-based liquid reagent to said housing.

15. A flue-gas processing system in accordance with claim 14 wherein said membrane contactor comprises a hydrophobic material.

16. A flue-gas processing system in accordance with claim 14 wherein said membrane contactor comprises an expanded polytetrafluoroethylene material.

17. A flue-gas processing system in accordance with claim 14 wherein said membrane contactor comprises a plurality of hollow fibers.

18. A flue-gas processing system in accordance with claim 17 wherein said plurality of hollow fibers is packaged in a tube-and-shell arrangement.

19. A flue-gas processing system in accordance with claim 14 wherein said membrane contactor comprises a substantially planar sheet.

20. A flue-gas processing system in accordance with claim 19 wherein said substantially planar sheet is packaged as a spiral-wound module.