Carbon dioxide isolating device and method

A method for separating carbon dioxide, the method comprising the steps of:

• allowing carbon dioxide in an off-gas to react with an absorbent solution in an absorption column so as to strip the carbon dioxide from the off-gas;
• removing the carbon dioxide from the absorbent solution in a regeneration column to regenerate the absorbent solution;
• introducing the absorbent solution into an anode chamber space;
• introducing the absorbent solution into a cathode chamber space divided from the anode chamber space by a permeable membrane;
• and
• ion-exchanging the first absorbent solution, introduced into the anode chamber space, with the second absorbent solution introduced into the cathode chamber space, by the permeable membrane,
• wherein cations in the absorbent solution discharged from the absorption column are ion-exchanged with anions of the absorbent solution discharged from the regeneration column, thereby reducing the concentration of carbon dioxide in the absorbent solution and increasing the concentration of ammonia in the absorbent solution,
• wherein reducing the concentration of carbon dioxide in the absorbent solution is performed by introducing the absorbent into an anode chamber space provided with an anode plate, and moving carbon dioxide of the absorbent solution in the anode chamber space through a permeable membrane to a cathode chamber space provided with a cathode plate, and
• wherein increasing the concentration of ammonia in the absorbent solution is performed by introducing the absorbent solution into a cathode chamber space provided with a cathode plate, and moving ammonium NH4+) of the absorbent solution in the cathode chamber space through a permeable membrane to an anode chamber space provided with an anode plate.

A method for separating carbon dioxide, the method comprising treating an off-gas in an absorption column in which carbon dioxide in the off-gas is allowed to react with an ammonia-containing absorbent solution so as to strip the carbon dioxide from the off-gas and in a regeneration column in which the carbon dioxide is removed from the absorbent solution to regenerate the absorbent solution,

• wherein cations in the absorbent solution discharged from the absorption column are ion-exchanged with anions of the absorbent solution discharged from the regeneration column, thereby reducing the concentration of carbon dioxide in the absorbent solution and increasing the concentration of ammonia in the absorbent solution,
• wherein reducing the concentration of carbon dioxide in the absorbent solution is performed by introducing the absorbent into an anode chamber space provided with an anode plate, and moving carbon dioxide of the absorbent solution in the anode chamber space through a permeable membrane to a cathode chamber space provided with a cathode plate, and
• wherein increasing the concentration of ammonia in the absorbent solution is performed by introducing the absorbent solution into a cathode chamber space provided with a cathode plate, and moving ammonium (NH4+) of the absorbent solution in the cathode chamber space through a permeable membrane to an anode chamber space provided with an anode plate.

An apparatus for separating carbon dioxide, comprising:

• an absorption column in which carbon dioxide in off-gas is allowed to react with an absorbent solution so as to strip the carbon dioxide from the off-gas;
• a regeneration column in which the carbon dioxide is removed from the absorbent solution to regenerate the absorbent solution;
• a chamber having a cathode chamber space provided with a cathode plate and an anode chamber space provided with an anode plate;
• a permeable membrane disposed between the cathode plate and the anode plate so as to divide the chamber into the cathode chamber space and the anode chamber space, wherein cations in the absorbent solution discharged from the absorption column are ion-exchanged with anions of the absorbent solution discharged from the regeneration column, thereby reducing the concentration of carbon dioxide in the absorbent solution and increasing the concentration of ammonia in the absorbent solution, wherein reducing the concentration of carbon dioxide in the absorbent solution is performed by introducing the absorbent into an anode chamber space provided with an anode plate, and moving carbon dioxide of the absorbent solution in the anode chamber space through a permeable membrane to a cathode chamber space provided with a cathode plate, and wherein increasing the concentration of ammonia in the absorbent solution is performed by introducing the absorbent solution into a cathode chamber space provided with a cathode plate, and moving ammonium (NH4+) of the absorbent solution in the cathode chamber space through a permeable membrane to an anode chamber space provided with an anode plate;
• and
• a gas scrubber which receives a gas from the chamber and scrubs the gas.