CAPTURE DE CO2 PAR UNITE CRYOGENIQUE SUR UNE CENTRALE DE TYPE GAZEIFICATION INTEGREE A CYCLE COMBINE

摘要

The method comprises: carrying out first partial condensation of the feed gas (5) for producing a first liquid enriched in carbon dioxide and a first overhead gas depleted in the carbon dioxide; purifying the top gas from the first phase separator by a purification unit (M) providing a first gas enriched in carbon dioxide and a second carbon dioxide depleted gas ( 11); and carrying out partial condensation of a set of streams containing carbon dioxide from the carbon dioxide-enriched gas from the purification unit to produce a second carbon dioxide-rich liquid. The method comprises: carrying out first partial condensation of the feed gas (5) for producing a first liquid (7) enriched in carbon dioxide and a first overhead gas depleted in the carbon dioxide; purifying the top gas from the first phase separator by a purification unit (M) providing a first gas enriched in carbon dioxide and a second carbon dioxide depleted gas ( 11); carrying out partial condensation of a set of streams containing carbon dioxide from the carbon dioxide-enriched gas from the purification unit to produce a second carbon dioxide-rich liquid; sending the first and second liquids to a distillation column (K); and producing a liquid containing 99% of carbon dioxide. The distillation column reboils the liquids by directly injecting the carbon dioxide gas at a bottom of the column or with the use of an indirect heat exchanger in the bottom of the column. The purification unit comprises a set of stages of membrane separation. The overhead gas from the distillation column is recycled to the feed gas. A gas is compressed before being recycled to the feed gas under pressure. A residue of the first membrane in the purification unit is condensed.