Hydrogen production with reduced carbon dioxide generation and complete capture

A method of reducing the carbon dioxide production and shifting balance from a reformer furnace flue gas to the high pressure syngas exit water gas shift reaction unit, comprising;

• a) providing a first gas mixture;
• b) heating said first stream mixture to a first temperature, then introducing said heated first gas mixture into at least one pre-reforming chamber, thereby producing a pre-reformed mixture;
• said heating being provided by indirect heat exchange with one or more of an SMR furnace flue gas or an SMR furnace syngas.
• c) further heating said pre-reformed mixture in a primary reformer, thereby generating a second gas mixture comprising hydrogen, carbon monoxide, carbon dioxide, and a flue gas, wherein said primary reformer comprises tubes filled with catalyst;
• d) introducing said second gas mixture into at least one isothermal shift reactor, or a combination of high followed by a low temperature shift reactor, or a medium temperature shift reactor, thereby generating a third gas mixture;
• e) introducing said third gas mixture into an amine wash, thereby producing an carbon dioxide enriched stream and a sweet syngas stream,
• f) introducing said sweet syngas stream into a standard H2 PSA unit, wherein said sweet syngas stream is separated into a hydrogen enriched stream and a PSA tail gas stream;
• g) introducing said PSA tail gas stream as fuel into the reformer furnace along with natural gas, a portion of the feed hydrocarbon stream, a portion of the hydrogen enriched stream, or any other external make-up fuel for the reformer furnace,
• wherein step b) is repeated twice, for a total of three pre-reforming steps, where the pre-reforming chamber comprises a total of three beds of pre-reformer catalyst, the temperature at the second pre-reformer is higher than the first pre-reformer, and the temperature at the third pre-reformer is higher than at the second,
• wherein the pre-reforming chamber comprises at least three beds of catalyst, wherein an outlet gas from each pre-reformer is heated up in a coil in exchange with SMR furnace flue gas or process syngas before going to a next pre-reformer reactor or before entering the main reformer tubes.