Method and system for removing carbon dioxide from exhaust gas by utilizing seawater

A method for removing carbon dioxide in an exhaust gas utilizing seawater, comprising:

• contacting seawater with an exhaust gas , not cooled and more than 100° C., to evaporate moisture in the seawater and thus produce concentrated seawater of which concentration of salt is increased;
• blowing ammonia into the concentrated seawater so as to be saturated, thereby producing ammonia-saturating concentrated seawater;
• contacting an exhaust gas under a state of non-heat with the ammonia-saturating concentrated seawater so that carbon dioxide in the exhaust gas is absorbed in the ammonia-saturating concentrated seawater;
• recovering a sediment of sodium hydrogen carbonate produced through absorption of the carbon dioxide by the ammonia-saturating concentrated seawater;
• and
• splaying a solution containing ammonium chloride which is produced through the absorption of the carbon dioxide by the ammonia-saturating concentrated seawater utilizing pressure of the exhaust gas while cooling the solution utilizing heat of evaporation of a solvent of the solution so as to settle out and recover the ammonium chloride.

A system for removing carbon dioxide in an exhaust gas utilizing seawater, comprising:

• a carbon dioxide absorbing tank for reserving ammonia-saturated seawater produced by blowing ammonia into seawater so as to be saturated and contacting an exhaust gas under a state of non-heat with the ammonia-saturated seawater so that carbon dioxide in the exhaust gas is absorbed in the ammonia-saturated seawater;
• a reservoir for reserving a solution containing sodium hydrogen carbonate and ammonium chloride which are produced through absorption of the carbon dioxide in the exhaust gas by the ammonia-saturated seawater;
• a first settling tank for splaying the solution utilizing pressure of the exhaust gas and cooling the solution utilizing heat of evaporation of a solvent of the solution so as to settle out and recover the sodium hydrogen carbonate;
• and
• a second settling tank for splaying the solution utilizing the pressure of the exhaust gas and cooling the solution utilizing the heat of evaporation of the solvent of the solution so as to settle out and recover the ammonium chloride.