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A process for recovery of CO2 from a post-combustion gas includes pre-concentrating a CO2 component of the post-combustion flue gas by passing the post-combustion gas through a CO2-selective membrane module to provide a CO2-enriched permeate stream and a CO2-lean reject stream. Next, in a CO2 absorb

A process for recovery of CO2 from a post-combustion gas includes pre-concentrating a CO2 component of the post-combustion flue gas by passing the post-combustion gas through a CO2-selective membrane module to provide a CO2-enriched permeate stream and a CO2-lean reject stream. Next, in a CO2 absorber, both the CO2-enriched permeate stream and CO2 lean reject stream, fed to separate feed locations on the CO2 absorber, are contacted with a scrubbing solvent to absorb CO2 and provide a carbon-rich scrubbing solvent. Finally, absorbed CO2 is stripped from the carbon-rich scrubbing solvent by a two-stage CO2 stripping system. The CO2-selective membrane may be a high flux, low pressure drop, low CO2 selectivity membrane. The two stage stripping system includes a primary CO2 stripping column for stripping CO2 from the carbon-rich scrubbing solvent exiting the CO2 absorber, and a secondary CO2 stripping column for stripping CO2 from a carbon-lean scrubbing solvent exiting the primary CO2 stripping column. Apparatus for CO2 removal from post-combustion gases in a pulverized coal power plant incorporating the described processes are described.

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1. A process for removal and recovery of CO2 from a post-combustion flue gas, comprising: pre-concentrating a CO2 component of the post-combustion flue gas by passing the post-combustion flue gas through a CO2-selective membrane module to provide a CO2-enriched permeate stream and a CO2-lean reject

1. A process for removal and recovery of CO2 from a post-combustion flue gas, comprising: pre-concentrating a CO2 component of the post-combustion flue gas by passing the post-combustion flue gas through a CO2-selective membrane module to provide a CO2-enriched permeate stream and a CO2-lean reject stream;in a CO2 absorber, contacting the CO2-enriched permeate stream and the CO2-lean reject stream with a scrubbing solvent to absorb CO2 and provide a carbon-rich scrubbing solvent; andstripping absorbed CO2 from the carbon-rich scrubbing solvent by a two-stage CO2 stripping system. 2. The process of claim 1, further including evaporating at least a portion of a water component of a post-combustion flue gas condensate for use as a carrier vapor for a permeate side of the CO2-selective membrane module. 3. The process of claim 1, further including passing a CO2-rich permeate stream from the CO2-selective membrane module to a feed point disposed at a bottom portion of the CO2 absorber and passing the CO2-lean reject stream from the CO2-selective membrane module to an intermediate feed point above the CO2 absorber bottom portion feed point. 4. The process of claim 1, further including providing a CO2-membrane module comprising a high flux, low pressure drop, low CO2 selectivity membrane. 5. The process of claim 1, further including providing a two stage stripping system comprising: a primary CO2 stripping column for stripping CO2 from the carbon-rich scrubbing solvent exiting the CO2 absorber; anda secondary CO2 stripping column for stripping CO2 from a carbon-lean scrubbing solvent exiting the primary CO2 stripping column. 6. The process of claim 5, including providing an ambient pressure air-swept, packed column secondary CO2 stripping column. 7. The process of claim 1, including providing a CO2 absorber having a bottom packing portion with a first cross-sectional dimension, and a top packing portion with a second cross-sectional dimension that is different from the first cross-sectional dimension. 8. The process of claim 1, including providing one or more intercoolers at intermediate positions of the CO2 absorber. 9. The process of claim 7, wherein the first cross-sectional dimension is approximately ⅓ that of the second cross-sectional dimension. 10. The process of claim 6, including passing a CO2-enriched air source exiting the secondary CO2 stripping column to a preheater and therefrom as a boiler combustion air for a pulverized coal boiler of a pulverized coal plant. 11. A CO2 capture and recovery system for recovery of CO2 from a post-combustion gas, comprising: a CO2-selective membrane module for pre-concentrating a CO2 component of an SO2-depleted post-combustion gas to provide a CO2-enriched permeate stream and a CO2-lean reject stream;a CO2 absorber for providing a carbon-rich scrubbing solvent by contacting the CO2-enriched permeate stream and the CO2-lean reject stream with a scrubbing solvent to absorb CO2; anda two-stage CO2 stripping system for stripping absorbed CO2 from the carbon-rich scrubbing solvent. 12. The system of claim 11, further including a moisture separator or condenser for removing at least a portion of a water vapor component of the CO2-enriched permeate stream. 13. The system of claim 11, wherein the CO2-enriched permeate stream from the CO2-selective membrane module is passed to a feed point disposed at a bottom of the CO2 absorber and the CO2-lean reject stream from the CO2-selective membrane module is passed to an intermediate feed point above the CO2-absorber bottom feed point. 14. The system of claim 11, wherein the CO2-membrane module comprises a high flux, low pressure drop, low CO2-selectivity membrane. 15. The system of claim 11, wherein the two stage stripping system comprises: a primary CO2 stripping column for stripping CO2 from the carbon-rich scrubbing solvent exiting the CO2 absorber; anda secondary CO2 stripping column for stripping CO2 from a carbon-lean scrubbing solvent exiting the primary CO2 stripping column. 16. The system of claim 15, wherein the secondary CO2 stripping column is an ambient pressure air-swept, packed column CO2 stripping column. 17. The system of claim 15, wherein the CO2 absorber includes a bottom packing portion with a first cross-sectional dimension and a top packing portion with a second cross-sectional dimension that is different from the first cross-sectional dimension. 18. The system of claim 11, wherein the CO2 absorber further includes one or more intercoolers disposed at intermediate positions of the CO2 absorber. 19. The system of claim 17, wherein the first cross-sectional dimension is approximately ⅓ that of the second cross-sectional dimension. 20. The system of claim 16, wherein a CO2-enriched air source exiting the secondary CO2 stripping column is passed to a preheater and therefrom to a pulverized coal boiler of a pulverized coal power plant as a boiler combustion air. 21. A pulverized coal-fired power plant comprising the CO2 capture and recovery system of claim 11.