An absorbent according to the present invention absorbs CO 2 or H 2 S contained in flue gas emitted from a power generating plant such as a thermal plant, and contains three or more amine compounds selected from linear or cyclic amine compounds having a primary amino group, and linear or cyclic amine compounds having a secondary amino group. By way of a synergetic effect of the mixture of these compounds, the absorption speed of CO 2 or H 2 S absorption is improved. A small amount of CO 2 contained in a large amount of boiler flue gas can be absorbed efficiently.
1. An absorbent that absorbs CO 2 or H 2 S contained in gas, the absorbent comprising:
a main component which is 2-ethylaminoethanol (EAE);
minor components selected from any one of the following combinations:
1-(2-aminoethyl)piperazine (AEPRZ) and any one of piperazine (P), methylpiperazine (MP), 2-amino-2-methylpropanol (AMP) and piperidinol (PDN);
piperazine (P) and piperidinol (PDN);
methylpiperazine (MP) and piperidinol (PDN); and
2-amino-2-methylpropanol (AMP) and piperidinol (PDN); and
water;
wherein the main component accounts for 30 to 55 weight percent, the minor components account for 20 to 1 weight percent, and the water accounts for the remaining weight percent.
2. A CO 2 or H 2 S reducing apparatus that reduces CO 2 or H 2 S contained in gas, the CO 2 and H 2 S reducing apparatus comprising:
an absorber that brings gas containing CO 2 or H 2 S into contact with absorbent to reduce CO 2 or H 2 S contained in the gas; and
a regenerator that recycles a solvent that has absorbed CO 2 or H 2 S, wherein
the solvent having CO 2 or H 2 S reduced and recycled in the regenerator is reused in the absorber, and
the absorbent according to claim 1 is used.
3. A CO 2 or H 2 S reducing method comprising:
reducing CO 2 or H 2 S in gas by bringing the gas containing CO 2 or H 2 S into contact with absorbent, and
recycling a solvent that has absorbed CO 2 or H 2 S so that the solvent having CO 2 or H 2 S reduced and recycled is reused, wherein
the absorbent according to claim 1 is used as the absorbent.