Patent ID: 7294327

Claim:
A continuous process for removing acid gases from a syngas comprising a sequence of at least two stages, each stage comprising the steps of (a) condensing acid gases from the syngas by cooling the syngas by non-contact heat exchange to produce liquefied acid gases, (b) separating the liquefied acid gases from the syngas, and (c) evaporating the liquefied acid gases to provide the cooling of the syngas in step (a), with the stages in the sequence being designated stage 1 through stage N, the letter N representing the number of stages in the sequence, with each of the stages in the sequence cooling the syngas to a successively lower temperature as the syngas progresses from stage 1 to stage N, and each of the stages in the sequence evaporating the liquefied acid gases at successively lower pressures, said successively lower pressures being within a range of a maximum of about 800 psia to a minimum of about 6 psia, thereby separately producing an acid gas product stream from each of the stages, with stage N discharging a purified syngas, wherein at least two of the acid gas product streams from the stages are pressurized and then sequestered.