Separation of carbon dioxide and hydrogen

• Main Authors: HINDERINK ANTONIE PIETER, HUDA BADRUL, VAN DER POL EVERT, HARPER ROGER NEIL, FORSYTH JONATHAN ALEC
• Format: Patent
• Language: Chinese; English
• Published: 18.08.2010
• 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

A process for separating hydrogen and carbon dioxide from a synthesis gas stream comprising carbon dioxide and hydrogen, said process comprising: (A) feeding a shifted synthesis gas stream at a pressure of at least 50 bar gauge to at least one membrane separator unit that is provided with membrane having a selectivity for H2 over CO2 of greater than 16 and withdrawing a hydrogen enriched permeate stream having a CO2 content of less than 10 mole % and a carbon dioxide enriched retentate stream having a CO2 content of at least 63 mole % CO2, preferably, at least 70 mole % CO2 from the membrane separator unit; (B) feeding the carbon dioxide enriched retentate stream to a carbon dioxide condensation plant where the retentate stream is cooled to condense out liquid CO2 by: (i) passing the carbon dioxide enriched retentate stream through a heat exchanger where the retentate stream is cooled against an external refrigerant to below its dew point thereby forming a cooled stream comprising a liquid phase and a vapour