Oxy-fuel combustion is one of the most promising methods for CO 2 capture and storage (CCS) but the operating costs-mainly due to the need for oxygen production-usually lead to an obvious decrease in power generation efficiency. An "oxy-enrich combustion" process was proposed in this study to improve the efficiency of the oxy-fuel combustion process. The oxidizer for oxy-enrich combustion was composed of pure oxygen, air and recycled flue gas. Thus, the CO 2 concentration in the flue gas

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... ed to 30-40%. The PSA (pressure swing adsorption), which has been widely used for CO 2 removal from the shifting gases of ammonia synthesis in China, was applied to capture CO 2 during oxy-enrich combustion. The technological economics of oxy-enrich combustion with PSA was calculated and compared to that of oxy-fuel combustion. The results indicated that, compared with oxy-fuel combustion: (1) the oxy-enrich combustion has fewer capital and operating costs for the ASU (air separation unit) and the recycle fan; (2) there were fewer changes in the components of the flue gas in a furnace for oxy-enrich combustion between dry and wet flue gas circulation; and (3) as the volume ratio of air and oxygen was 2 or 3, the economics of oxy-enrich combustion with PSA were more advantageous.