Hydrogen generating apparatus using steam reforming reaction

摘要

The present invention provides a hydrogen generator for generating hydrogen through a steam-reforming process using hydrocarbons as a raw material and a method of operating the same, and, more particularly, provides a hydrogen generator for generating hydrogen through a steam reforming process, which can be stably operated because water is introduced into the hydrogen generator in the form of single phase vapor, and which can achieve high thermal efficiency using a proper heat exchanging method, and to a method of operating the same. According to the present invention, there is provided a heat exchanger network, in which heat necessary for a reforming reaction are obtained by the heat exchange of high-temperature exhaust gas or reformed gas, and in which, in a water gas converting reaction and a PSA reaction conducted at low temperatures compared to the reforming reaction, heat exchange is performed by low-temperature air or water, and the heat-exchanged air and the residual gas in the PSA reaction are used as a heat supply source for the reforming reactor together with fuel hydrocarbons, thereby minimizing the thermal loss of the hydrogen generator.

主权项

1. A hydrogen generator using steam reforming, having a reforming reaction of a mixture of a desulfurized hydrocarbon feed and a water feed by heating the mixture using a burner to form a reformed gas; a water gas converter for converting carbon monoxide (CO) in the reformed gas obtained from the reformer into a converted gas of hydrogen (H2) and carbon dioxide (CO2); and a pressure swing absorption (PSA) unit for separating hydrogen (H2) from the converted gas; characterized in that the hydrogen generator comprises:
a first heat exchanger for superheating the water feed to higher than an evaporation temperature of water through heat exchange with the exhaust gas discharged from the burner to convert the water feed into single-phase vapor before the water feed is mixed with the desulfurized hydrocarbons, thereby forming a mixture of the desulfurized hydrocarbon feed and the superheated water; a second heat exchanger for preheating the mixture of the desulfurized hydrocarbon feed and the superheated water through heat exchange with the reformed gas discharged from the reformer, whereby the superheated water is introduced into the reformer in such a state that a single vapor phase is maintained without phase separation of water; a third heat exchanger for decreasing a temperature of the reformed gas through heat exchange with external air before the reformed gas is introduced into the water gas converter; and a fourth heat exchanger for additionally decreasing a temperature of the gas discharged from the water gas converter through heat exchange with tap water before the converted gas is introduced into the PSA unit, wherein a bypass line for controlling an amount of air introduced into the third heat exchanger is further included to control a temperature of the reformed gas at an inlet of the water gas converter.