SYSTEM FOR RECOVERING CARBON DIOXIDE FROM FLUE GAS

• US 20110107916A1
• Filed: 01/26/2009
• Published: 05/12/2011
• Est. Priority Date: 07/23/2008
• Status: Active Grant

• Current Assignee: Mitsubishi Heavy Industries Engineering, Ltd. (Mitsubishi Heavy Industries, Ltd.)
• Original Assignee: Mitsubishi Heavy Industries, Ltd.
• Inventors: Tanaka, Hiroshi, Inoue, Katsufumi, Oishi, Tsuyoshi, Yonekawa, Takahito, Kamijo, Takashi
• Granted Patent: US 8,535,428 B2
• Time in Patent Office: Days
• US Class Current: 96/242
• CPC Class Codes: B01D 2251/80 Organic bases or salts
• CPC Class Codes: B01D 2252/20405 Monoamines
• CPC Class Codes: B01D 2252/20421 Primary amines
• CPC Class Codes: B01D 2252/20484 with one hydroxyl group
• CPC Class Codes: B01D 2258/0283 Flue gases
• CPC Class Codes: B01D 53/1418 Recovery of products
• CPC Class Codes: B01D 53/1425 Regeneration of liquid absorbents
• CPC Class Codes: B01D 53/1475 Removing carbon dioxide
• CPC Class Codes: F28D 3/02 with tubular conduits
• CPC Class Codes: Y02C 20/40 of CO2

Abstract

To include an absorber (1006) that brings CO₂ absorbent that absorbs CO₂ contained in flue gas (1002) into contact with the flue gas to remove CO₂ from the flue gas, a regenerator (1008) that strips CO₂ from CO₂ absorbent (rich solution), which is fed from the absorber through a first feed line L₁ and has absorbed CO₂, to regenerate CO₂ absorbent, thereby acquiring regenerated CO₂ absorbent (lean solution) (1009), falling film reboilers (1101-1 and 1101-2) that draw off CO₂ absorbent (amine solution) (1033) from near the bottom of the regenerator and reheats regenerated CO₂ absorbent via steam (1031), a first liquid-vapor separator (1103) that separates the CO₂ absorbent reheated by the falling film reboilers into regenerated CO₂ absorbent in which CO₂ has been removed and vapor containing CO₂, and a second feed line L₂ for supplying the separated regenerated CO₂ absorbent to the absorber.

Claims

1. A system for recovering carbon dioxide from flue gas, comprising:

an absorber that brings CO₂ absorbent that absorbs CO₂ contained in flue gas exhausted from industrial facilities into contact with the flue gas to remove CO₂ from the flue gas;

a regenerator that strips CO₂ from CO₂ absorbent that is fed from the absorber through a first feed line and has absorbed the CO₂ to regenerate CO₂ absorbent;

at least two falling film reboilers that draw off CO₂ absorbent from near a bottom of the regenerator and reheats CO₂ absorbent via steam;

a first liquid-vapor separator that separates CO₂ absorbent reheated by the falling film reboilers into CO₂ absorbent and vapor containing CO₂; and

a second feed line for supplying separated CO₂ absorbent to the absorber.

2. The system for recovering carbon dioxide from flue gas according to claim 1, further comprising:

a condenser that condenses water vapor from CO₂ gas carrying water vapor, extracted from a top part of the regenerator;

a second liquid-vapor separator that separates condensed water vapor; and

a CO₂ compressor that compresses CO₂ gas separated by the second liquid-vapor separator to acquire high-pressure CO₂ gas.

3. The system for recovering carbon dioxide from flue gas according to claim 1, wherein the falling film reboiler includes a channel cover for maintenance provided on the top thereof.

4. The system for recovering carbon dioxide from flue gas according to claim 1, wherein a reboiler system is constituted by the at least two falling film reboilers and one first liquid-vapor separator that separates falling liquid from the falling film reboilers into vapor and liquid, and a plurality of the reboiler systems are arranged for one regenerator.