Producing H2 and CO2 from partial oxidation gas

摘要

H2S, COS and CO2 are removed from shifted partial oxidation gas by (1) physical absorption in a first stage 106 to remove the H2S and some COS; (2) physical absorption in a second stage 107 to remove the CO2 and the balance of the COS together with some H2, CO and CH4; (3) desorption 129 of the second stage solvent to recover the CO2, COS, H2, CO and CH4; and (4) distillation 152 of the desorbed gases to recover the CO2 free from COS. The distillation may be arranged to give a product stream comprising CO2 together with H2, CO and CH4 or to give a product stream comprising CO2 substantially free of H2, CO and CH4. The first stage solvent may be expanded 114 to release H2 and CO2 for recycle 104 and then regenerated to remove H2S, COS and residual CO2 in column 125.