A process for removing a contaminant gas comprising sulfur dioxide from source gas and recovering the contaminant gas, the process comprising: contacting a feed gas stream comprising the source gas in a rich gas absorber with a rich gas aqueous absorption medium comprising a sorbent for a contaminant gas, thereby absorbing contaminant gas from the feed gas stream into the absorption medium and producing a lean gas from which contaminant gas has been removed and a rich absorption liquor containing sorbed contaminant; contacting the lean gas exiting said rich gas absorber in a lean gas absorber with a lean gas aqueous absorption medium comprising a sorbent for the contaminant gas, thereby absorbing residual contaminant gas from the lean gas into the lean gas absorption medium and producing an exhaust gas from which additional contaminant gas has been removed and a lean absorption liquor containing sorbed contaminant; heating said rich absorption liquor in a rich liquor stripper by contacting said rich absorption liquor with stripping steam to desorb said contaminant from said rich liquor and thereby produce a regenerated rich gas absorption medium and a rich liquor stripper gas effluent from said rich liquor stripper, said rich liquor stripper gas effluent comprising water vapor and contaminant gas; heating said lean absorption liquor in a lean liquor stripper by contacting said lean absorption liquor with stripping steam to desorb contaminant gas from said lean liquor and thereby produce a regenerated lean gas absorption medium and a lean liquor stripper gas effluent from said lean liquor stripper, said lean liquor stripper gas effluent comprising water vapor and said contaminant gas; and recirculating said regenerated rich gas absorption medium to said rich gas absorber for removal of contaminant gas from further flow of said feed gas and said regenerated lean gas absorption medium to said lean gas absorber for removal of contaminant gas from further flow of lean gas; wherein the ratio of steam delivered to the lean liquor stripper relative to the SO 2 content entering the lean gas absorber in the lean gas is higher than the ratio of steam delivered to the rich liquor stripper relative to the SO 2 content entering the rich gas absorber in the feed gas. contacting a feed gas stream comprising the source gas in a rich gas absorber with a rich gas aqueous absorption medium comprising a sorbent for a contaminant gas, thereby absorbing contaminant gas from the feed gas stream into the absorption medium and producing a lean gas from which contaminant gas has been removed and a rich absorption liquor containing sorbed contaminant; contacting the lean gas exiting said rich gas absorber in a lean gas absorber with a lean gas aqueous absorption medium comprising a sorbent for the contaminant gas, thereby absorbing residual contaminant gas from the lean gas into the lean gas absorption medium and producing an exhaust gas from which additional contaminant gas has been removed and a lean absorption liquor containing sorbed contaminant; heating said rich absorption liquor in a rich liquor stripper by contacting said rich absorption liquor with stripping steam to desorb said contaminant from said rich liquor and thereby produce a regenerated rich gas absorption medium and a rich liquor stripper gas effluent from said rich liquor stripper, said rich liquor stripper gas effluent comprising water vapor and contaminant gas; heating said lean absorption liquor in a lean liquor stripper by contacting said lean absorption liquor with stripping steam to desorb contaminant gas from said lean liquor and thereby produce a regenerated lean gas absorption medium and a lean liquor stripper gas effluent from said lean liquor stripper, said lean liquor stripper gas effluent comprising water vapor and said contaminant gas; and recirculating said regenerated rich gas absorption medium to said rich gas absorber for removal of contaminant gas from further flow of said feed gas and said regenerated lean gas absorption medium to said lean gas absorber for removal of contaminant gas from further flow of lean gas; wherein the ratio of steam delivered to the lean liquor stripper relative to the SO 2 content entering the lean gas absorber in the lean gas is higher than the ratio of steam delivered to the rich liquor stripper relative to the SO 2 content entering the rich gas absorber in the feed gas.