CO2 recovery device and CO2 recovery method

Patent metadata

Field	Value
Publication number	US-9901873-B2
Application number	US-201314420248-A
Country	US
Kind code	B2
Filing date	Jul 31, 2013
Priority date	Aug 9, 2012
Publication date	Feb 27, 2018
Grant date	Feb 27, 2018

Abstract

CO 2 absorber includes a CO 2 absorbing section in which a CO 2 -containing flue gas and a CO 2 absorbent are brought into contact with each other to remove CO 2 , and an aqueous cleaning section in which a decarbonated flue gas and rinsing water are brought into contact with each other to remove an accompanying substance. A lean solution is re-used in the absorber. The CO 2 recovery device includes a degassing basin which is interposed in a rich solution supply line that supplies the rich solution from the CO 2 absorber to the absorbent regenerator, and which includes a retaining section configured to remove oxygen in the rich solution.

First claim

The invention claimed is:

1. A CO 2 recovery device, comprising:
a CO 2 absorber including a CO 2 absorbing section in which a flue gas and a basic amine compound absorbent are brought into contact with each other to allow CO 2 in the flue gas to be absorbed in the basic amine compound absorbent, and an aqueous cleaning section in which a decarbonated flue gas, from which CO 2 is already removed in the CO 2 absorbing section, and rinsing water are brought into contact with each other to remove an accompanying substance that accompanies the decarbonated flue gas, and
an absorbent regenerator that separates CO 2 from a rich solution to which CO 2 is already absorbed, and regenerates the basic amine compound absorbent into a lean solution,
wherein the lean solution from which CO 2 is already removed is re-used as the basic amine compound absorbent in the CO 2 absorber; and
a degassing basin that is interposed in a rich solution supply line that supplies the rich solution from the CO 2 absorber to the absorbent regenerator,
wherein the degassing basin includes
the retaining section that retains the rich solution for a predetermined time and is configured to separate oxygen in the rich solution by floating separation,
a partition wall that allows the rich solution, from which oxygen is flotation separated in the retaining section, to gravity fall along a wall surface thereof and is configured to remove oxygen, and
a storage section that stores the rich solution which falls along the partition wall and from which oxygen is removed.

2. The CO 2 recovery device according to claim 1 , further comprising:
a purge gas introducing unit that purges a gas, which does not contain oxygen, into a space of the degassing basin.

3. The CO 2 recovery device according claim 1 , further comprising:
a degassing tower that is provided on a downstream side of the degassing basin, and further degasses the rich solution, from which oxygen is removed, in a decompressed state.

4. The CO 2 recovery device according to claim 1 , further comprising:
a heat exchange unit that is provided on an upstream side of the degassing basin, and heats the rich solution.

Assignees

• Mitsubishi Heavy Ind Ltd

Inventors

• Oishi Tsuyoshi
• Nagayasu Hiromitsu
• Tanaka Hiroshi
• Hirata Takuya
• Kamijo Takashi
• Shimada Daisuke

Classifications

• B01D2257/104

  Oxygen · CPC title

• Y02C10/06

  Cross-Sectional Technologies · mapped topic

• B01D53/62 Primary

  Carbon oxides · CPC title

• B01D53/1475

  Removing carbon dioxide · CPC title

• B01D2258/0283

  Flue gases · CPC title