A process for a multi-staged capture of CO 2 and H 2 S from a pressurized gas stream producing a clean pressurized gas stream containing less than 1 ppm H 2 S and less than 10 ppm CO 2 and achieving greater than 99.9% capture efficiency, wherein the pressure in said pressurized gas stream and said clean pressurized gas stream is above atmospheric pressure, comprising: (a) providing an alkaline solution containing 5-15 molal NH 3 ; (b) providing a first multistage absorber for absorbing CO 2 and H 2 S from said pressurized gas stream combined with said alkaline solution, wherein greater than 95% of said CO 2 and H 2 S content of said pressurized gas stream is captured in said alkaline solution, wherein a net loading of 110-330 grams of said CO 2 and H 2 S per 1000 grams of water is absorbed in said alkaline solution; (c) providing a second multistage polishing absorber using water for capturing the residual of CO 2 and H 2 S in said pressurized gas stream entrained from said first multistage absorber and NH 3 entrained from said first multistage absorber resulting in a gas outlet stream from said second multistage polishing absorber containing less than 10 ppm CO 2 and NH 3 and less than 1 ppm H 2 S; (d) providing a main stripper for stripping said CO 2 and H 2 S absorbed by said first multistage absorber in said alkaline solution, resulting in: (i) a pure gas stream exhausted containing greater than 99.7% CO 2 + H 2 S, less than 0.3% water vapor and less than 10 ppm of each of H 2 , CO, NH 3 and CH 4 , and (ii) said alkaline solution reduced of said stripped CO 2 and H 2 S which is sent back from said main stripper to said first multistage absorber; and (e) providing a sour water stripper for stripping said CO 2 , H 2 S and NH 3 absorbed by said second multistage polishing absorber in said water, and said water stripped of said CO 2 , H 2 S and NH 3 is sent back from said sour water stripper to said second multistage polishing absorber. (a) providing an alkaline solution containing 5-15 molal NH 3 ; (b) providing a first multistage absorber for absorbing CO 2 and H 2 S from said pressurized gas stream combined with said alkaline solution, wherein greater than 95% of said CO 2 and H 2 S content of said pressurized gas stream is captured in said alkaline solution, wherein a net loading of 110-330 grams of said CO 2 and H 2 S per 1000 grams of water is absorbed in said alkaline solution; (c) providing a second multistage polishing absorber using water for capturing the residual of CO 2 and H 2 S in said pressurized gas stream entrained from said first multistage absorber and NH 3 entrained from said first multistage absorber resulting in a gas outlet stream from said second multistage polishing absorber containing less than 10 ppm CO 2 and NH 3 and less than 1 ppm H 2 S; (d) providing a main stripper for stripping said CO 2 and H 2 S absorbed by said first multistage absorber in said alkaline solution, resulting in: (i) a pure gas stream exhausted containing greater than 99.7% CO 2 + H 2 S, less than 0.3% water vapor and less than 10 ppm of each of H 2 , CO, NH 3 and CH 4 , and (ii) said alkaline solution reduced of said stripped CO 2 and H 2 S which is sent back from said main stripper to said first multistage absorber; and (i) a pure gas stream exhausted containing greater than 99.7% CO 2 + H 2 S, less than 0.3% water vapor and less than 10 ppm of each of H 2 , CO, NH 3 and CH 4 , and (ii) said alkaline solution reduced of said stripped CO 2 and H 2 S which is sent back from said main stripper to said first multistage absorber; and (e) providing a sour water stripper for stripping said CO 2 , H 2 S and NH 3 absorbed by said second multistage polishing absorber in said water, and said water stripped of said CO 2 , H 2 S and NH 3 is sent back from said sour water stripper to said second multistage polishing absorber. <EOS>