NOVELTY - Producing hydrogen involves combining purified hydrocarbon stream with the purified hydrocarbon to generate pre-reformed gas mixture; generating crude synthesis gas mixture by using pre-reformed gas mixture; generating shifted synthesis gas mixture by using crude synthesis gas mixture; passing the shifted synthesis gas mixture to a membrane shift reactor; cooling the hydrogen-enriched gas mixture to generate a de-watered hydrogen-enriched gas mixture; and separating de-watered hydrogen-enriched gas mixture to generate a pure hydrogen stream and a purge gas stream.    USE - For producing hydrogen used as fuel to the fired steam reformer (claimed).    ADVANTAGE - The method minimizes the risk of carbon formation on the catalyst in steam reformer; and produces hydrogen with purity of 99.999%.    DETAILED DESCRIPTION - Producing hydrogen involves passing a hydrocarbon feed though at least one purification sorbent to generate a purified hydrocarbon stream; combining steam with the purified hydrocarbon and passing the hydrocarbon/steam mixture adiabatically through a bed of steam reforming catalyst disposed in a pre-reformer vessel to generate a pre-reformed gas mixture; passing the pre-reformed gas mixture through externally-heated catalyst filled tubes in a fired steam reformer to generate a crude synthesis gas mixture comprising hydrogen, carbon monoxide, carbon dioxide and steam; passing the crude synthesis gas mixture through beds of water-gas shift catalyst in at least one shift vessel to generate a shifted synthesis gas mixture; passing the shifted synthesis gas mixture to a membrane shift reactor containing a bed of water-gas shift catalyst and a carbon dioxide-selective membrane, in which the shifted synthesis gas mixture is subjected to the water-gas shift reaction over the water-gas shift catalyst, and carbon dioxide is separated from the resulting shifted gas mixture by the membrane, thereby generating a hydrogen-enriched gas mixture; cooling the hydrogen-enriched gas mixture to below the dew point and separating off the condensate to generate a de-watered hydrogen-enriched gas mixture; passing the de-watered hydrogen-enriched gas mixture to stages of carbon dioxide separation in pressure-swing absorption apparatus, to generate a pure hydrogen stream and a purge gas stream; and recycling at least a portion of the purge gas stream as fuel to the fired steam reformer or to the hydrocarbon feed or purified hydrocarbon feed streams.