Abstract:
The invention provides an electrolyte membrane that allows an operating temperature of a solid polymer membrane fuel cell to be raised and an operating temperature of a solid oxide fuel cell to be lowered. This electrolyte membrane can be used in a fuel cell that is operable in an intermediate temperature range. The invention also provides a fuel cell using such an electrolyte membrane. The electrolyte membrane has a hydrated electrolyte layer, and dense layers made of a hydrogen permeable material that are formed on both sides of this electrolyte layer. Both sides of the electrolyte membrane are coated with dense layers. Consequently, evaporation of moisture contained in the electrolyte layer is suppressed, and increase in the resistance of the membrane is inhibited. As a result, the range of the operating temperature of the fuel cell can be enlarged.
Abstract:
A hydrogen extraction unit has reformed gas flow channel plates, hydrogen separation plates, and purge gas flow channel plates, which are designed as thin metal plate members. The hydrogen extraction unit is constructed by laminating these thin plate members and then bonding them together by diffusion bonding. Each of reformed gas flow channel holes formed in the reformed gas flow channel plates constitutes a flow channel for reformed gas together with a correspondingly adjacent one of the hydrogen separation plates. Each of purge gas flow channel holes formed in the purge gas flow channel plates constitutes, together with a correspondingly adjacent one of the hydrogen separation plates, a flow channel for purge gas with which hydrogen extracted from reformed gas is mixed.
Abstract:
In a fuel reforming apparatus having a reformer for reforming a raw fuel containing a hydrocarbon-containing compound so as to produce a hydrogen-rich fuel gas for use in a fuel cell, a carbon removal process for removing carbon deposited on a reforming catalyst contained in the reformer is executed by controlling the amount of the raw fuel supplied to the reformer and the amount of the oxygen supplied to the reformer so that a ratio of the number of oxygen atoms O supplied to the reformer to the number of carbon atoms supplied to the reformer becomes larger than an appropriate range of the O/C ratio that is to be established during a normal operation of the reformer.
Abstract:
The technique of the present invention enhances the separation efficiency and the production efficiency of hydrogen in a hydrogen production system for fuel cells, while reducing the size of the whole fuel gas production system. In the fuel gas production system of the present invention, a hydrocarbon compound is subjected to multi-step chemical processes including a reforming reaction, a shift reaction, and a CO oxidation to give a hydrogen-rich fuel gas. Gaseous hydrogen produced through the reforming reaction is separated by a hydrogen separation membrane having selective permeability to hydrogen. The residual gas after the separation of hydrogen has a low hydrogen partial pressure and undergoes the shift reaction at the accelerated rate. The hydrogen-rich processed gas obtained through the shift reaction and the CO oxidation joins with the separated hydrogen and is supplied to fuel cells. A purge gas for carrying out the hydrogen is introduced into a separation unit of hydrogen, in order to lower the hydrogen partial pressure and thereby enhance the separation efficiency of hydrogen. The residual gas after the separation of hydrogen undergoes combustion and is subsequently used as the purge gas
Abstract:
A power system of the invention includes fuel cells and a fuel gas generation system that generates a fuel gas to be supplied to the fuel cells. At the time of stopping supply of hydrogen, the fuel gas generation system selectively uses a stop process that replaces hydrogen in a hydrogen separator unit with the air for removal of hydrogen and a pause process that allows hydrogen to remain in the hydrogen separator unit. The stop process is selected when the fuel gas generation system stops the supply of hydrogen for a long time period. The pause process is selected when the fuel gas generation system temporarily stops the supply of hydrogen. The arrangement of the invention desirably shortens a restart time of the fuel gas generation system and reduces a potential energy loss.
Abstract:
In a fuel cell system 10, a cracking unit 20 is provided upstream of a reformer 36. When the cracking unit 20 is supplied with oxygen and gasoline as a hydrocarbon-based fuel, the gasoline is partially oxidized and decomposed using oxidation-generated heat to give a hydrocarbon with a lower carbon number. The hydrocarbon with the lower carbon number obtained by such gasoline pyrolysis is fed to the reformer 36 and supplied to a reforming reaction zone.
Abstract:
A fuel reforming apparatus includes a premixed fuel tank. In the premixed fuel tank, premixed fuel which is formed by emulsifying gasoline and water that are mixed with each other at a predetermined ratio, using a emulsifier. The premixed fuel is sprayed into a vaporizing portion through a nozzle. Heat can be supplied to the vaporizing portion by the reformer in which oxidation reaction proceeds, a first heating portion, and air supplied to the vaporizing portion through a heat exchanger. The premixed fuel sprayed into the vaporizing portion is vaporized immediately by the thus supplied heat, and is supplied to the reformer. In addition, air which has been humidified in a humidifying module cam be supplied to the vaporizing portion.
Abstract:
A fuel reforming apparatus includes a reforming catalyst, a filtering member, a raw material supply flow passage and a processed gas flow passage. The filtering member has a plurality of cells. A reforming catalyst is carried on a surface of a partition on the side of the processed gas flow passage. If raw gas including hydrocarbon fuel is supplied to the fuel reforming apparatus and filtered by the filtering member, soot included in the raw gas is trapped by gaps in the partition, and the hydrocarbon fuel is reformed into reformed gas including hydrogen and carbon monoxide on the reforming catalyst. By increasing the amount of air supplied from a blower at intervals of time, the soot trapped by the partition is removed by combustion.