Process for sulfur removal and recovery from a power generation plant using physical solvent

Claim 1

A process for producing a hydrogen sulfide-free fuel gas for combustion in a gas turbine to produce power using a raw fuel feed gas from an oxygen-enriched gasification, comprising the steps of: (a) introducing a raw fuel feed gas from a gasification, which gas is contaminated with hydrogen sulfide and carbon dioxide, into a first separation zone; (b) contacting said raw fuel feed gas with a carbon dioxide-loaded liquid solvent selective for said hydrogen sulfide in said first separation zone; (c) removing a hydrogen sulfide-free, carbon dioxide-containing fuel gas from said first separation zone, combusting the hydrogen sulfide-free, carbon dioxide-containing fuel gas in a gas turbine and recovering power from the gas turbine; (d) removing a hydrogen sulfide-rich, carbon dioxide-containing solvent from said first separation zone and reducing said solvent in pressure; (e) heating said reduced pressure solvent to an elevated temperature before separating said reduced pressure solvent into a carbon dioxide-rich stream and a second hydrogen sulfide-rich solvent containing residual carbon dioxide; (f) stripping said residual carbon dioxide from said second hydrogen sulfide-rich solvent with nitrogen-rich gas at a pressure below approximately 300 psia to recover a residual carbon dioxide containing nitrogen stripping gas; (g) combining said carbon dioxide-rich stream of step (e) and said residual carbon dioxide containing nitrogen stripping gas of step (f) and recycling the resulting combined stream to the hydrogen sulfide-free, carbon dioxide-containing fuel gas; (h) stripping the hydrogen sulfide from said second hydrogen sulfide-rich solvent in a regeneration zone using steam to recover a hydrogen sulfide-rich product stream and a hydrogen sulfide-lean solvent; and (i) combining said hydrogen sulfide-lean solvent with said hydrogen sulfide-free, carbon dioxide-containing fuel gas either outside said first separation zone or in a top tray of said first separation zone, cooling them and separating them into said carbon dioxide-loaded liquid solvent of step (b) and a final hydrogen sulfide-free, carbon dioxide-containing fuel gas for introduction into said gas turbine of step (c).