Patent ID: 8021464
Filing Date: 2011-09-20
Classification: B01D,C01B,F25J,Y02C,Y02P

Abstract:
1. A method for the combined production of hydrogen and carbon dioxide from a mixture of hydrocarbons, comprising at least: (a) generating a syngas containing at least carbon dioxide, hydrogen, carbon monoxide, methane, and water vapor, from said hydrocarbon mixture; (b) cooling the syngas issuing from (a) with recovery of the available waste heat; (c) back-converting, to steam, all or part of the cooled syngas issuing from (b) in order to oxidize most of the carbon monoxide it contains to carbon dioxide, with the corresponding production of hydrogen; (d) cooling the mixture issuing from step (c), with condensation of the steam, by heat exchange with various boiler feedwater and/or deionized water circuits; (e) purifying the cooled mixture issuing from (d) in a pressure swing adsorption (PSA) unit to obtain a hydrogen-enriched stream having a purity at least equal to 98% and an offgas called “PSA offgas” containing carbon dioxide, at a pressure of about 1 to 3 bar abs; and steps of treating said PSA offgas to obtain a carbon dioxide-enriched fluid, comprising at least: (f) compressing the PSA offgas to a pressure higher than the reforming pressure and such that the partial pressure of the CO (g) drying the compressed PSA offgas by removing the water therein to obtain a dry gas; and (h) two or more successive steps (hn) of condensation/separation, such that using the incondensables purge.