Patent ID: 8940258
Filing Date: 2015-01-27
Classification: B01D,Y02C

Abstract:
1. A process for selectively removing and recovering a contaminant gas from a contaminant-containing source gas, the process comprising: contacting a feed gas stream comprising the source gas in a contaminant gas absorber with an aqueous absorption medium comprising a sorbent for the contaminant gas, thereby absorbing contaminant gas from the feed gas stream into the absorption medium and producing an exhaust gas from which contaminant gas has been removed and a contaminant-enriched absorption liquor; contacting the contaminant-enriched absorption liquor with stripping steam in an absorption liquor stripper to desorb the contaminant from the contaminant-enriched absorption liquor and thereby produce a regenerated contaminant absorption medium and a primary stripper gas effluent comprising water vapor and contaminant gas; withdrawing regenerated absorption medium from a liquid outlet of the absorption liquor stripper and primary stripper gas effluent from a vapor outlet of the absorption liquor stripper; compressing the primary stripper gas effluent; condensing water from the compressed primary stripper gas effluent by indirect transfer of heat from the compressed primary stripper gas effluent to a cooling medium in a primary stripper gas cooler/condenser to thereby produce a contaminant-bearing condensate; contacting the contaminant-bearing condensate exiting the primary stripper gas cooler/condenser with steam in a condensate stripper to produce a stripped condensate and a condensate stripper gas effluent containing water vapor and contaminant gas; wherein the cooling medium to which heat is transferred from the compressed primary stripper gas effluent in the primary stripper gas cooler/condenser comprises at least a portion of the stripped condensate, thereby generating steam from the stripped condensate at a pressure in excess of the pressure within the absorption liquor stripper at the liquid outlet thereof; and introducing steam generated from the stripped condensate in the primary stripper gas cooler/condenser into the absorption liquor stripper as stripping steam for contact with contaminant-enriched absorption liquor to desorb contaminant therefrom.