CO2 recovery unit and CO2 recovery method

Patent metadata

Field	Value
Publication number	US-9383101-B2
Application number	US-201113580469-A
Country	US
Kind code	B2
Filing date	Jan 11, 2011
Priority date	Feb 23, 2010
Publication date	Jul 5, 2016
Grant date	Jul 5, 2016

Abstract

A CO 2 recovery unit includes an absorber that reduces CO 2 in flue gas ( 101 ) discharged from a combustion facility ( 50 ) by absorbing CO 2 by an absorbent, a regenerator that heats the absorbent having absorbed CO 2 to emit CO 2 , and regenerates and supplies the absorbent to the absorber, and a regenerating heater that uses steam ( 106 ) supplied from the combustion facility ( 50 ) for heating the absorbent in the regenerator and returns heated condensed water ( 106 a ) to the combustion facility ( 50 ). The CO 2 recovery unit further includes a condensed water/flue gas heat exchanger ( 57 ) that heats the condensed water ( 106 a ) to be returned from the regenerating heater to the combustion facility ( 50 ) by heat-exchanging the condensed water ( 106 a ) with the flue gas ( 101 ) in a flue gas duct ( 51 ) in the combustion facility ( 50 ).

First claim

The invention claimed is:

1. A plant comprising:
a combustion facility that discharges flue gas to a flue gas duct and heats condensed water from a condensed water line so as to discharge the heated condensed water to a steam extracting line as steam;
an air/flue gas heat exchanger that heat-exchanges the flue gas with combustion air;
a CO 2 recovery including:
an absorber that reduces CO 2 in flue gas discharged from the combustion facility via the air/flue gas heat exchanger by absorbing CO 2 by an absorbent;
a regenerator that heats the absorbent having absorbed CO 2 to emit CO 2 , and regenerates and supplies the absorbent to the absorber; and
a regenerating heater that heats the absorbent in the regenerator with the steam from the steam extracting line and returns heated condensed water to the combustion facility via the condensed water line; and

a condensed water/flue gas heat exchanger that heats the condensed water of the condensed water line by heat-exchanging the condensed water with the flue gas in the flue gas duct discharged from the air/flue gas heat exchanger.

2. The plant according to claim 1 , wherein a condensed water/flue gas heat exchanging line for heat-exchanging between the condensed water and the flue gas is provided in middle of the condensed water line, and a bypass line for directly connecting the condensed water line without via the condensed water/flue gas heat exchanging line is provided.

3. The plant according to claim 1 , further comprising:
a circulating water/flue gas heat exchanger that performs heat exchange between circulating water and flue gas in a flue gas duct in the combustion facility, at a downstream of flue gas of the condensed water/flue gas heat exchanger; and
a circulating water/absorbent heat exchanger that performs heat exchange between an absorbent having absorbed CO 2 in the absorber and the circulating water before the absorbent reaches the regenerator.

4. The plant according to claim 1 , further comprising an air preheater that preheats combustion air before reaching the combustion facility by waste heat discharged in a process of recovering CO 2 .

5. The plant according to claim 1 further comprising an air preheater that preheats combustion air before reaching the combustion facility by the condensed water before reaching the condensed water/flue gas heat exchanger.

Assignees

• Tsujiuchi Tatsuya
• Nagayasu Hiromitsu
• Hirata Takuya
• Fujikawa Keiji
• Imai Tetsuya
• Tanaka Hiroshi
• Oishi Tsuyoshi
• Tatsumi Masahiko
• Yagi Yasuyuki
• Kaibara Kazuhiko
• Mitsubishi Heavy Ind Ltd
• Kansai Electric Power Co

Inventors

• Tsujiuchi Tatsuya
• Nagayasu Hiromitsu
• Hirata Takuya
• Fujikawa Keiji
• Imai Tetsuya
• Tanaka Hiroshi
• Oishi Tsuyoshi
• Tatsumi Masahiko
• Yagi Yasuyuki
• Kaibara Kazuhiko

Classifications

• F23L15/04

  Arrangements of recuperators · CPC title

• B01D53/1475

  Removing carbon dioxide · CPC title

• B01D2258/0283

  Flue gases · CPC title

• F23J2215/20

  Sulfur; Compounds thereof · CPC title

• Y02E20/348

  Cross-Sectional Technologies · mapped topic