| 摘要 |
In the treatment of a gas containing a mixture of hydrocarbons, H2S and possibly CO2, at least part at pressure P2 is put in contact with a recycled polar solvent of which at least 50% is solvent in an adsorption zone (2). The solvent is a non-hydrocarbon organic compound which is normally liquid other than water, at least partially miscible with water and distillable at a temperature below that of water. This produces a purified gas containing most of the hydrocarbons and almost no H2S and a first liquid comprising the solvent, the remaining hydrocarbons and effectively all the H2S and CO2. The solvent is regenerated in at least one distillation column (18), and the regenerated solvent is recycled and refrigerated in the adsorption zone. The first liquid is expanded and heated to a pressure P12 less than P2 in a heat exchange column (12) which exchanges heat in counter-flow with the regenerated and heated solvent. A second gas is recovered at the top of the column, containing effectively all the remaining hydrocarbons and most of the CO2, and at the bottom a second heated liquid is recovered containing the solvent, most of the H2S and a small part of the CO2. The solvent is regenerated by circulating the second liquid, after expansion, through the distillation column at a pressure P18 at most equal to the pressure P12. At least part of a third acid gas is recovered at the top, containing most of the H2S and the remaining CO2, and at the bottom of the column the regenerated and heated solvent is recovered and cooled inside the heat exchange column and the solvent recovered and recycled under pressure in the adsorption zone. Also claimed is a device to carry out the above process.
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