COMPLEX AMINE ABSORBENT, AND DEVICE AND METHOD FOR REMOVING ONE OR BOTH OF CO2 AND H2S

• US 20150132207A1
• Filed: 04/25/2013
• Published: 05/14/2015
• Est. Priority Date: 05/11/2012
• Status: Active Grant

• Current Assignee: Kansai Electric Power Company Incorporated, Mitsubishi Heavy Industries, Ltd.
• Original Assignee: Kansai Electric Power Company Incorporated, Mitsubishi Heavy Industries, Ltd.
• Inventors: Tanaka, Hiroshi, Nagayasu, Hiromitsu, Hirata, Takuya, Oishi, Tsuyoshi, Kamijo, Takashi
• Granted Patent: US 10,137,407 B2
• Time in Patent Office: Days
• US Class Current: 423/229
• CPC Class Codes: B01D 2252/20405 Monoamines
• CPC Class Codes: B01D 2252/2041 Diamines
• CPC Class Codes: B01D 2252/20421 Primary amines
• CPC Class Codes: B01D 2252/20426 Secondary amines
• CPC Class Codes: B01D 2252/20447 containing a piperazine-ring
• CPC Class Codes: B01D 2252/20484 with one hydroxyl group
• CPC Class Codes: B01D 2252/504 Mixtures of two or more absorbents
• CPC Class Codes: B01D 2257/304 Hydrogen sulfide
• CPC Class Codes: B01D 2257/504 Carbon dioxide
• CPC Class Codes: B01D 2258/0283 Flue gases
• CPC Class Codes: B01D 53/1425 Regeneration of liquid absorbents
• CPC Class Codes: B01D 53/1462 Removing mixtures of hydrogen sulfide and carbon dioxide
• CPC Class Codes: B01D 53/1493 Selection of liquid materials for use as absorbents
• CPC Class Codes: B01D 53/526 Mixtures of hydrogen sulfide and carbon dioxide
• CPC Class Codes: B01D 53/78 with gas-liquid contact
• CPC Class Codes: B01J 20/22 comprising organic material
• CPC Class Codes: Y02C 20/40 of CO2

Abstract

An absorbent is prepared by dissolving in water 1) monoethanolamine (MEA) and 2) a primary amine represented by the following formula (1) and having high steric hindrance. Releasability of CO₂ or H₂S during regeneration of the absorbent is thereby improved, and the amount of water vapor used during regeneration of the absorbent in a facility for recovering CO₂ or H₂S can be reduced.

R₁ to R₃: H or a hydrocarbon group having 1 to 3 carbon atoms, at least one of R₁ to R₃ being a hydrocarbon.

Claims

1. A complex amine absorbent for absorbing one or both of CO₂ and H₂S in a gas, the complex amine absorbent comprisingmonoethanolamine (MEA), anda primary amine represented by the following formula (1) and having high steric hindrance, with the monoethanolamine and the primary amine being dissolved in water,

2. The complex amine absorbent according to claim 1, wherein the primary amine having high steric hindrance is at least one of 2-amino-1-propanol, 2-amino-1-butanol, 2-amino-3-methyl-1-butanol, 1-amino-2-propanol, 1-amino-2-butanol, and 2-amino-2-methyl-1-propanol.

4. The complex amine absorbent according to claim 1, wherein

the linear poly primary and secondary amines are ethylenediamine, N,N′

-dimethylethylenediamine, N,N′

-diethylethylenediamine, propanediamine, and N,N′

-dimethylpropanediamine, and

the cyclic polyamines are piperazine, 1-methylpiperazine, 2-methylpiperazine, 2,5-dimethylpiperazine, 1-(2-aminoethyl)piperazine, and 1-(2-hydroxyethyl)piperazine.

5. The complex amine absorbent according to claim 1, wherein

the complex amine absorbent is circulated and reused in an absorbing-removing facility including an absorber for absorbing one or both of CO₂ and H₂S in the gas and a regenerator in which the one or both of CO₂ and H₂S absorbed are released to regenerate the absorbent,

a pressure inside the regenerator is 130 to 200 kPa (absolute pressure),

an absorption temperature in the absorber is 30 to 80°

C., and

a regeneration temperature in the regenerator is 110°

C. or higher.

6. A device for removing one or both of CO₂ and H₂S, the device comprising:

an absorber for removing one or both of CO₂ and H₂S by bringing a gas containing one or both of CO₂ and H₂S in contact with an absorbent; and

a regenerator for regenerating a solution containing the one or both of CO₂ and H₂S absorbed therein, the solution regenerated by removing the one or both of CO₂ and H₂S in the regenerator being reused in the absorber, wherein

the complex amine absorbent according to claim 1 is used.

7. A method of removing one or both of CO₂ and H₂S, the method comprising:

bringing a gas containing one or both of CO₂ and H₂S in contact with an absorbent to remove the one or both of CO₂ and H₂S;

regenerating a solution containing one or both of CO₂ and H₂S absorbed therein; and

reusing, in an absorber, the solution regenerated by removing the one or both of CO₂ and H₂S in a regenerator, wherein

the complex amine absorbent according to claim 1 is used to remove the one or both of CO₂ and H₂S.

3. (canceled)