Patent ID: 8163046

Claim:
A start-up process for a thermally-integrated hydrogen production unit that comprises: (a) supplying a start-up burner whose purpose is to ensure start-up of the unit with a mixture of hydrocarbon feedstock and air, burning said mixture, and heating with hot effluents that are obtained from said burner a gaseous stream that enters a reforming reactor and that exits therefrom, until the temperature of the stream that is obtained from said reforming reactor reaches a value of more than 200° C., (b) after (a) evaporating a stream of water by indirect heat exchange with at least one hot stream from the process, generating a stream of water vapor that enters said reforming reactor until the stream that is obtained from this reactor reaches a temperature of more than 300° C. and all of the water is evaporated, (c) after (b) evaporating liquid hydrocarbon feedstock that is to be reformed or heating gaseous feedstock to be reformed, by indirect heat exchange with at least one of the hot streams of the process; introducing said feedstock into the reforming reactor, enabling the production of a hydrogen-rich effluent stream, (d) after (c) replacing the start-up burner with a burner that is in permanent operation, supplied by a mixture of residual air and gas discharged by a section for purification of the hydrogen-rich stream, wherein effluent obtained from the reforming reactor enters and then leaves from a reactor converting carbon monoxide with water (WGS), positioned downstream from said reforming reactor, during all the stages of the start-up process.