CO2 recovery system and CO2 recovery method

Patent metadata

Field	Value
Publication number	US-9623366-B2
Application number	US-201313784173-A
Country	US
Kind code	B2
Filing date	Mar 4, 2013
Priority date	Mar 4, 2013
Publication date	Apr 18, 2017
Grant date	Apr 18, 2017

Abstract

A CO 2 recovery system includes an absorption apparatus that brings a CO 2 absorption liquid into contact with an exhaust gas treated by a pre-treatment apparatus so that CO 2 in the exhaust gas is absorbed into the CO 2 absorption liquid; a regeneration apparatus that separates CO 2 from the CO 2 absorption liquid; an absorption liquid circulation path that circulates the CO 2 absorption liquid between the absorption apparatus and the regeneration apparatus; and an impurity removal unit that removes impurities having a high concentration in the absorption liquid circulation path, in the absorption liquid circulation path and/or in the pre-treatment apparatus in advance.

First claim

The invention claimed is:

1. A CO 2 recovery system comprising:
a pre-treatment apparatus that cools an exhaust gas;
an absorption apparatus that brings a CO 2 absorption liquid into contact with the exhaust gas treated by the pre-treatment apparatus so that CO 2 in the exhaust gas is absorbed into the CO 2 absorption liquid;
a regeneration apparatus that receives the CO 2 absorption liquid having absorbed CO 2 from the absorption apparatus and heats the CO 2 absorption liquid to separate CO 2 from the CO 2 absorption liquid;
an absorption liquid circulation path that circulates the CO 2 absorption liquid between the absorption apparatus and the regeneration apparatus; and
an impurity removal unit, provided in the absorption liquid circulation path, that removes impurities dissolved in the CO 2 absorption liquid and having a high concentration in the absorption liquid circulation path from the exhaust gas, the impurity removal unit including:
a reclaimer that draws and heats the CO 2 absorption liquid of the absorption liquid circulation path, heats and concentrates impurities in the CO 2 absorption liquid, and returns condensate water to the regeneration apparatus; and
an ion-exchange apparatus that brings the CO 2 absorption liquid of an absorption liquid drawing path that supplies the CO 2 absorption liquid from the absorption liquid circulation path to the reclaimer into contact with an ion-exchange resin to remove the impurities.

2. A CO 2 recovery system comprising:
a pre-treatment apparatus that cools an exhaust gas;
an absorption apparatus that brings a CO 2 absorption liquid into contact with the exhaust gas treated by the pre-treatment apparatus so that CO 2 in the exhaust gas is absorbed into the CO 2 absorption liquid;
a regeneration apparatus that receives the CO 2 absorption liquid having absorbed CO 2 from the absorption apparatus and heats the CO 2 absorption liquid to separate CO 2 from the CO 2 absorption liquid;
an absorption liquid circulation path that circulates the CO 2 absorption liquid between the absorption apparatus and the regeneration apparatus; and
an impurity removal unit, provided in the absorption liquid circulation path, that removes impurities dissolved in the CO 2 absorption liquid and having a high concentration in the absorption liquid circulation path from the exhaust gas, the impurity removal unit including:
a reclaimer that draws and heats the CO 2 absorption liquid of the absorption liquid circulation path, heats and concentrates impurities in the CO 2 absorption liquid, and returns condensate water to the regeneration apparatus; and
a coagulation sedimentation treatment apparatus that coagulates and sediments the CO 2 absorption liquid of an absorption liquid drawing path that supplies the CO 2 absorption liquid from the absorption liquid circulation path to the reclaimer, to remove the impurities.

3. The CO 2 recovery system according to claim 2 , wherein:
the coagulation sedimentation treatment apparatus is configured to adjust the pH of the CO 2 absorption liquid using CO 2 separated in the regeneration apparatus.

4. A CO 2 recovery system comprising:
a pre-treatment apparatus that cools an exhaust gas;
an absorption apparatus that brings a CO 2 absorption liquid into contact with the exhaust gas treated by the pre-treatment apparatus so that CO 2 in the exhaust gas is absorbed into the CO 2 absorption liquid;
a regeneration apparatus that receives the CO 2 absorption liquid having absorbed CO 2 from the absorption apparatus and heats the CO 2 absorption liquid to separate CO 2 from the CO 2 absorption liquid;
an absorption liquid circulation path that circulates the CO 2 absorption liquid between the absorption apparatus and the regeneration apparatus; and
an impurity removal unit, provided in the absorption liquid circulation path, that removes impurities dissolved in the CO 2 absorption liquid and having a high concentration in the absorption liquid circulation path from the exhaust gas, the impurity removal unit including:
a reclaimer that draws and heats the CO 2 absorption liquid of the absorption liquid circulation path, heats and concentrates impurities in the CO 2 absorption liquid, and returns condensate water to the regeneration apparatus; and
an ion-exchange apparatus that brings concentrated residue generated from the reclaimer into contact with an ion-exchange resin to remove the impurities.

5. A CO 2 recovery system comprising:
a pre-treatment apparatus that cools an exhaust gas;
an absorption apparatus that brings a CO 2 absorption liquid into contact with the exhaust gas treated by the pre-treatment apparatus so that CO 2 in the exhaust gas is absorbed into the CO 2 absorption liquid;
a regeneration apparatus that receives the CO 2 absorption liquid having absorbed CO 2 from the absorption apparatus and heats the CO 2 absorption liquid to separate CO 2 from the CO 2 absorption liquid;
an absorption liquid circulation path that circulates the CO 2 absorption liquid between the absorption apparatus and the regeneration apparatus; and
an impurity removal unit, provided in the absorption liquid circulation path, that removes impurities dissolved in the CO 2 absorption liquid and having a high concentration in the absorption liquid circulation path from the exhaust gas, the impurity removal unit including:
a reclaimer that draws and heats the CO 2 absorption liquid of the absorption liquid circulation path, heats and concentrates impurities in the CO 2 absorption liquid, and returns condensate water to the regeneration apparatus; and
a coagulation sedimentation treatment apparatus that coagulates and sediments concentrated residue generated from the reclaimer to remove the impurities.

6. A CO 2 recovery system comprising:
a pre-treatment apparatus that cools an exhaust gas;
an absorption apparatus that brings a CO 2 absorption liquid into contact with the exhaust gas treated by the pre-treatment apparatus so that CO 2 in the exhaust gas is absorbed into the CO 2 absorption liquid;
a regeneration apparatus that receives the CO 2 absorption liquid having absorbed CO 2 from the absorption apparatus and heats the CO 2 absorption liquid to separate CO 2 from the CO 2 absorption liquid;
an absorption liquid circulation path that circulates the CO 2 absorption liquid between the absorption apparatus and the regeneration apparatus; and
an impurity removal unit, provided in the absorption liquid circulation path, that removes impurities dissolved in the CO 2 absorption liquid and having a high concentration in the absorption liquid circulation path from the exhaust gas, the impurity removal unit including:
a reclaimer that draws and heats the CO 2 absorption liquid of the absorption liquid circulation path, heats and concentrates impurities in the CO 2 absorption liquid, and returns condensate water to the regeneration apparatus; and
an electrodialysis treatment apparatus that performs electrodialysis on concentrated residue generated from the reclaimer to remove the impurities.

7. The CO 2 recovery system according to claim 6 , wherein:
the pre-treatment apparatus includes a scrubber, and
acidic treated water generated by treatment in the electrodialysis treatment apparatus of the impurity removal unit is supplied as cleaning water for acid cleaning of the scrubber of the pre-treatment apparatus.

8. A CO 2 recovery system comprising:
a pre-treatment apparatus that cools an exhaust gas;
an absorption apparatus that brings a CO 2 absorption liquid into contact with the exhaust gas treated by the pre-treatment apparatus so that CO 2 in the exhaust gas is absorbed into the CO 2 absorption l

Assignees

• Mitsubishi Heavy Ind Ltd

Inventors

• Tsujiuchi Tatsuya
• Yonekawa Takahito
• Honjo Shintaro
• Inui Masayuki
• Nakayama Koji
• Kamijo Takashi
• Nagayasu Hiromitsu

Classifications

• Y02C10/06

  Cross-Sectional Technologies · mapped topic

• B01D2252/20489

  with two or more hydroxyl groups · CPC title

• B01D53/1425

  Regeneration of liquid absorbents · CPC title

• C02F1/5236

  using inorganic agents · CPC title

• B01D2258/0283

  Flue gases · CPC title