Separation of carbon dioxide and hydrogen

• Main Authors: HINDERINK, ANTONIE PIETER, HARPER, ROGER NEIL, HUDA, BADRUL, VAN DER POL, EVERT
• Format: Patent
• Language: English; French; German
• Published: 11.02.2009
• Subjects: BLASTING; CHEMISTRY; COMBINED HEATING AND REFRIGERATION SYSTEMS; COMPOUNDS THEREOF; HEAT PUMP SYSTEMS; HEATING; INORGANIC CHEMISTRY; LIGHTING; LIQUEFACTION SOLIDIFICATION OF GASES; LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS; MANUFACTURE OR STORAGE OF ICE; MECHANICAL ENGINEERING; METALLURGY; MIXTURES BY PRESSURE AND COLD TREATMENT; NON-METALLIC ELEMENTS; PERFORMING OPERATIONS; PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL; REFRIGERATION OR COOLING; SEPARATION; TRANSPORTING; WEAPONS

This invention relates to recovering carbon dioxide (77) and hydrogen (31) in concentrated form from a shifted synthesis gas stream (1) comprising hydrogen and carbon dioxide thereby generating a carbon dioxide stream that is sequestered or used for enhanced oil recovery and a hydrogen stream that is used as fuel for a power plant thereby generating electricity. In the process of this invention a shifted synthesis gas stream is fed to a membrane separation unit (M-1) at a pressure of at least 50 bar gauge and the hydrogen rich permeate stream (3) is fed directly to the combustor of a gas turbine without any requirement to recompress the hydrogen. The residual gas stream (carbon dioxide enriched stream 2) from the membrane separation unit is cooled using at least one, preferably, at least two internal refrigeration stages (Ex-2,Ex-3,Ex-4,Ex-5,Ex-6,Ex-7,Ex-8) such that the hydrogen containing offgas (29) is also obtained at above the operating pressure of the combustor of the gas turbine.