Regenerative type carbon dioxide separator and carbon dioxide separating system

• US 6,521,026 B1
• Filed: 06/20/2001
• Issued: 02/18/2003
• Est. Priority Date: 10/20/1999
• Status: Expired due to Fees

• Current Assignee: ALSTOM K.K. (Alstom SA)
• Original Assignee: ALSTOM K.K. (Alstom SA)
• Inventors: Goto, Kazushige
• Primary Examiner(s): Simmons, David A.
• Assistant Examiner(s): LAWRENCE JR, FRANK M
• Application Number:
  US09/868,579
• Time in Patent Office: 608 Days
• Field of Search: 951/13, 951/39, 961/22, 961/25, 961/26, 961/27, 961/28, 961/30, 961/43, 961/46, 423/230, 423/437.1
• US Class Current: 96/122
• CPC Class Codes: B01D 2251/30 Alkali metal compounds
• CPC Class Codes: B01D 2251/40 Alkaline earth metal or magnesium compounds
• CPC Class Codes: B01D 2251/602 Oxides
• CPC Class Codes: B01D 2253/25 Coated, impregnated or composite adsorbents
• CPC Class Codes: B01D 2256/22 Carbon dioxide
• CPC Class Codes: B01D 2257/504 Carbon dioxide
• CPC Class Codes: B01D 2258/0291 from waste incineration plants
• CPC Class Codes: B01D 2259/4009 using hot gas
• CPC Class Codes: B01D 53/02 by adsorption, e.g. preparative gas chromatography solid sorbent compositions B01J20/00, preparation of inorganic compounds or elements C01
• CPC Class Codes: B01D 53/06 with moving adsorbents, e.g. rotating beds B01D53/025 takes precedence
• CPC Class Codes: C01B 32/50 Carbon dioxide
• CPC Class Codes: F28D 19/044 shaped in sector form, e.g. with baskets
• CPC Class Codes: Y02C 20/40 of CO2
• CPC Class Codes: Y02P 20/151 Reduction of greenhouse gas [GHG] emissions, e.g. CO2

Abstract

A rotor includes a high-temperature section and a low-temperature section on its circumference. It is possible to absorb and separate carbon dioxide gas in an effluent or exhaust gas simply by rotating the rotor. Therefore, it is possible to obtain a reliable absorbing/separating system. The system can be remarkably simplified, the regenerating cost thereof can be considerably reduced, and the maintenance thereof is easy. A fixed type of system has similar advantages. Lithium zirconate, an alkali metal oxide, and/or an alkali earth metal oxide is used as an absorbing/separating agent. Such an absorbing/separating agent is chemically and mechanically stable, and can absorb and release carbon dioxide gas stably and reversibly.

Claims

1. A carbon dioxide gas separating system comprising:

a regenerative carbon dioxide gas separator including;

a rotatable rotor;

an absorbing/separating agent housed in said rotor, for absorbing carbon dioxide gas at a temperature lower than a predetermined temperature, and for releasing the absorbed carbon dioxide gas at a temperature higher than the predetermined temperature;

a first gas flow passage for passing a first gas through said rotor in a direction substantially parallel to a central axis of rotation of said rotor;

a second gas flow passage for passing a second gas through said rotor in a direction substantially parallel to the central axis of rotation of said rotor; and

a sealing mechanism for preventing the mixing of said first gas and said second gas,

wherein carbon dioxide gas contained in said first gas is absorbed by said absorbing/separating agent and the carbon dioxide gas absorbed by said absorbing/separating agent is released into said second gas by rotating said rotor while the temperature of said first gas flow passage is set to be lower than said predetermined temperature and the temperature of said second gas flow passage is set to be higher than said predetermined temperature;

heating means for heating said second gas flow passage of said regenerative carbon dioxide gas separator to a temperature higher than said predetermined temperature;

heat recovering means for cooling a gas flowing out of said first gas flow passage; and

heat exchanging means for transferring heat energy from a gas containing carbon dioxide gas flowing out of said second gas flow passage to said first gas supplied to said first gas flow passage.

2. The carbon dioxide gas separating system according to claim 1 further comprising circulating means for re-supplying at least part of the gas containing carbon dioxide gas flowing out of said second gas flow passage to said second gas flow passage,

wherein said heating means is a regenerative burner or an indirect type furnace for burning a fuel to heat the gas containing carbon dioxide gas circulated by said circulating means.

3. The carbon dioxide gas separating system according to claim 1, wherein said heat recovering means includes a boiler for generating steam by the use of the gas flowing out of said first gas flow passage.

4. The carbon dioxide gas separating system according to claim 1, wherein said heat recovering means includes a boiler for generating steam by the use of the gas flowing out of said first gas flow passage, a steam turbine driven by the steam generated by said boiler, and a generator driven by said steam turbine.

5. The carbon dioxide gas separating system according to claim 1, wherein said heat exchanging means is any of plate-type, tubular-type, or rotary-type of regenerative heat exchanger.

6. A carbon dioxide gas separating system comprising:

a regenerative carbon dioxide gas separator comprising;

a plurality of reaction chambers;

an absorbing/separating agent housed in said plurality of reaction chambers, which absorbs carbon dioxide gas at a temperature lower than a predetermined temperature and releases the absorbed carbon dioxide gas at a temperature higher than the predetermined temperature; and

switching means for selectively supplying one of first gas and second gas to said plurality of reaction chambers;

wherein the regenerative carbon dioxide gas separator sequentially performs in the reaction chambers;

absorption cycles in which said first gas is supplied to a reaction chamber to form a first gas flow passage while the temperature of the reaction chamber is maintained to be lower than the predetermined temperature, and said absorbing/separating agent absorbs carbon dioxide gas contained in said first gas; and

regeneration cycles in which said second gas is supplied to the reaction chamber to form a second gas flow passage while the temperature of the reaction chamber is maintained to be higher than the predetermined temperature, and said absorbing/separating agent releases the absorbed carbon dioxide gas into the second gas;

heating means for heating said second gas flow passage of said regenerative carbon dioxide gas separator to a temperature higher than said predetermined temperature;

heat recovering means for cooling a gas flowing out of said first gas flow passage; and

heat exchanging means for transferring heat energy from a gas containing carbon dioxide gas flowing out of said second gas flow passage to said first gas supplied to said first gas flow passage.

7. The carbon dioxide gas separating system according to claim 6 further comprising circulating means for re-supplying at least part of the gas containing carbon dioxide gas flowing out of said second gas flow passage to said second gas flow passage,

wherein said heating means is a regenerative burner or an indirect type furnace for burning a fuel to heat the gas containing carbon dioxide gas circulated by said circulating means.

8. The carbon dioxide gas separating system according to claim 6, wherein said heat recovering means includes a boiler for generating steam by the use of the gas flowing out of said first gas flow passage.

9. The carbon dioxide gas separating system according to claim 6, wherein said heat recovering means includes a boiler for generating steam by the use of the gas flowing out of said first gas flow passage, a steam turbine driven by the steam generated by said boiler, and a generator driven by said steam turbine.

10. The carbon dioxide gas separating system according to claim 6, wherein said heat exchanging means is any of plate-type, tubular-type, or rotary-type of regenerative heat exchanger.