Patent ID: 8845788
Filing Date: 2014-09-30
Classification: B01D,C10K,Y02P

Abstract:
1. A method of treating an H2S- and CO2-containing syngas, comprising: absorbing in an absorber at syngas pressure H2S and CO2 from the H2S- and CO2-containing syngas using a lean physical solvent to so form a treated CO2-containing syngas and a rich solvent comprising H2S and CO2, wherein the lean physical solvent is a H2S selective physical solvent; heating and flashing the rich solvent comprising H2S and CO2 in at least two successive flash stages to produce respective flash gases enriched in CO2 and respective flashed rich solvents comprising H2S, wherein the step of heating the rich solvent in the at least two stages uses heat from the lean solvent; cooling the flash gases to form respective cooled flash gases and respective condensate streams, recycling the flash gases enriched in CO2 to the syngas or absorber and feeding the condensate streams into a stripper; and regenerating the condensate streams and the flashed rich solvent comprising H2S in the stripper to so form the lean physical solvent and an H2S rich acid gas stream that has a CO2 content of at least 30 mol % and an H2S to CO2 ratio of at least 1.1:1.