Patent ID: 8486182

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