| 主权项 |
1. A process for reducing carbon dioxide emissions from a combined cycle power generation
process utilizing a gaseous hydrocarbon feed, comprising the steps of: (i) dividing the gaseous hydrocarbon feed into two portions; a first smaller portion comprising ≦45% by volume of the gaseous hydrocarbon feed and a second larger portion comprising ≧55% by volume of the gaseous hydrocarbon feed, (ii) subjecting a mixture comprising the first smaller portion and steam to adiabatic steam reforming by passing the mixture though a bed of steam reforming catalyst, to form a pre-reformed gas mixture, (iii) autothermally reforming the pre-reformed gas mixture by partially combusting the pre-reformed gas mixture with an oxygen-containing gas to form a partially combusted gas and bringing the partially combusted gas towards equilibrium over a reforming catalyst in an autothermal reformer, thereby forming a reformed gas mixture comprising hydrogen, steam and carbon oxides, (iv) increasing the hydrogen content of the reformed gas mixture by subjecting it to one or more water-gas-shift stages thereby producing a hydrogen-enriched reformed gas, (v) cooling the hydrogen-enriched reformed gas to below the dew point of the steam therein to condense water and separating condensed water to give a de-watered hydrogen-enriched reformed gas, (vi) passing the de-watered hydrogen-enriched reformed gas to one or more stages of carbon dioxide separation to generate a carbon dioxide stream and a hydrogen-containing stream, (vii) mixing the hydrogen-containing stream with the second larger portion of the gaseous hydrocarbon feed to form a hydrogen-containing fuel stream, and (viii) combusting the hydrogen-containing fuel stream with a second oxygen-containing gas in a gas turbine to generate electrical power and an exhaust gas mixture, and passing the exhaust gas mixture to a heat recovery steam generation system to provide steam for one or more steam turbines to generate additional electrical power. |
