JP4484585B2 - Reformer - Google Patents

Description

  The present invention relates to a reformer that generates a hydrogen-containing gas containing hydrogen as a main component and supplied to a fuel electrode of a fuel cell from a hydrocarbon-based raw fuel.

  The reformer as described above has a combustion section that burns the fuel for heating, and a reformer that generates hydrogen-containing gas mainly composed of hydrogen by reforming the raw fuel with steam while heating with the combustion gas of the combustion section. And a water vapor generating part that heats water with combustion gas after heating the reforming part of the combustion part and generates water vapor supplied to the reforming part. Hydrogen-containing gas is supplied to the fuel electrode of the fuel cell through the hydrogen-containing gas flow path, while the fuel off-gas in which hydrogen discharged from the fuel electrode of the fuel cell remains is passed through the fuel off-gas flow path to the heating fuel. It is comprised so that it may supply and burn to a combustion part (for example, refer patent document 1).

  In such a reformer, a raw fuel supply amount adjusting means such as an adjustment valve capable of adjusting the raw fuel supply amount to the reforming section is provided. By controlling the operation of the supply amount adjusting means, the hydrogen-containing gas supply amount to the fuel electrode of the fuel cell can be set to an appropriate value that matches the output of the fuel cell.

  Further, in such a reformer, water supply amount adjusting means such as an adjustment valve capable of adjusting the water supply amount to the steam generation unit is provided. For example, the control means operates the water supply amount adjusting means. By controlling the amount of water supplied to the steam generating unit relative to the amount of raw fuel supplied corresponding to the ratio of the amount of water vapor to the amount of carbon contained in the raw fuel in the reforming unit (hereinafter referred to as the steam-carbon ratio). It can be set to an appropriate one suitable for the steam reforming reaction.

  The reformer described in Patent Document 1 supplies a hydrogen-containing gas to the fuel electrode of the fuel cell, and supplies the hydrogen-containing gas to the combustion unit as a heating fuel by bypassing the fuel electrode of the fuel cell. A switching means capable of switching between the bypass state and the control means, wherein the control means switches the switching means to the supply state and operates the fuel cell, and switches the switching means to the bypass state. And a self-sustaining operation mode in which the fuel cell is stopped while continuing the generation of the hydrogen-containing gas. And because the temperature of the reformer is not stable, it is impossible to obtain a hydrogen-containing gas with a low carbon monoxide concentration, or when the fuel cell is not ready to accept the hydrogen-containing gas as its fuel The control means implements a self-sustaining operation mode to stop the supply of the hydrogen-containing gas to the fuel electrode of the fuel cell and supply the entire amount of the hydrogen-containing gas generated in the reforming unit to the combustion unit. Thus, it is possible to continue the operation of the reformer while burning.

  Further, in the reformer, carbon monoxide contained in the hydrogen-containing gas discharged from the reforming unit is converted into carbon dioxide in a hydrogen-containing gas passage through which the hydrogen-containing gas generated in the reforming unit flows. The reforming unit is provided with a selective oxidation unit that contacts and oxidizes carbon monoxide contained in the carbon monoxide contained in the hydrogen-containing gas discharged from the transformation unit. In order to maintain the temperature of the metamorphic part and the selective oxidation part within an appropriate range, the combustion part, the reforming part, the metamorphic part, and the selective oxidation part are adjacent to each other so that heat conduction is possible between them. A reformer is known (see Patent Document 2).

JP 2003-203658 A JP 2002-356309 A

  However, in the reformer disclosed in Patent Document 1, when the operation of the raw fuel supply amount adjusting means is controlled and the raw fuel supply amount to the reforming unit is set to be equal to that in the rated operation in the self-sustaining operation mode. Since the hydrogen-containing gas equivalent to that at the rated operation of the fuel cell is supplied as it is to the combustion chamber and combusted, the calorific value in the combustion section is increased compared to that at the rated operation. Accordingly, in such a reforming apparatus, if such a self-sustaining operation mode is continued for a certain time or more, the temperature of various processing units such as the reforming unit exceeds an appropriate range, and further, the various processing units There is a problem that thermal damage occurs to the provided casing and catalyst.

  The present invention has been made in view of the above-described problems, and an object thereof is to provide a reformer capable of continuing the above-described self-sustained operation mode for a relatively long time.

In order to achieve the above object, a reforming apparatus according to the present invention comprises a combustion section for combusting a heating fuel, and reforming with steam while heating a hydrocarbon-based raw fuel with the combustion gas of the combustion section. A reforming unit that generates a hydrogen-containing gas whose main component is water, and steam that heats water with the combustion gas after heating the reforming unit of the combustion unit and generates water vapor supplied to the reforming unit A generating unit, a supply state of supplying the hydrogen-containing gas to a fuel electrode of a fuel cell, and a bypass state of supplying the hydrogen-containing gas to the combustion unit as the heating fuel by bypassing the fuel electrode of the fuel cell. A switching means capable of switching; a raw fuel supply amount adjusting means capable of adjusting a raw fuel supply amount to the reforming unit; a water supply amount adjusting means capable of adjusting a water supply amount to the steam generating unit; Switch the switching means to the supply state. Changing the total amount of the hydrogen-containing gas generated in the switching and the reforming section in the bypass state the normal operation mode and the switching means for operating the fuel cell is burned in the combustion section, the fuel cell A reforming apparatus comprising a control means having a self-sustaining operation mode for continuing the production of the hydrogen-containing gas in a stopped state ,
In the self-sustained operation mode, the control means sets the raw fuel supply amount as a self-sustained operation target raw fuel supply amount for self-sustained operation, which is less than a rated target raw fuel supply amount when the fuel cell is rated-operated. In addition, a self-sustained operation target for self-sustaining operation in which a steam-carbon ratio, which is a ratio of the water supply amount to the raw fuel supply amount, is increased from a rated target steam-carbon ratio when the fuel cell is rated-operated. This is to control the operations of the raw fuel supply amount adjusting means and the water supply amount adjusting means so that the steam-carbon ratio is obtained.

According to the first characteristic configuration, when the control unit selects the self-sustaining operation mode in which the fuel cell is stopped while continuing the generation of the hydrogen-containing gas by switching the switching unit to the bypass state, the raw fuel supply amount adjusting unit By controlling the operation of the fuel cell so that the raw fuel supply amount is set to the above-mentioned self-sustained operation target raw fuel supply amount that is reduced compared to the rated operation of the fuel cell, the calorific value in the combustion section becomes relatively low. By controlling the operation of the water supply amount adjusting means in addition to the fuel supply amount adjusting means, the steam / carbon ratio is increased to be higher than that during rated operation of the fuel cell, and the above-mentioned independent operation target steam / carbon ratio is obtained. The heat consumption for heating water into steam in the steam generation section and the heat consumption for raising the steam temperature to the reforming temperature in the reforming section are relatively increased.
Therefore, in the self-sustained operation mode, as described above, the heat generation amount in the combustion section decreases, and furthermore, the heat consumption in the steam generation section increases, so that the temperatures of various processing sections such as the reforming section are appropriate. Exceeding the range can be suppressed, and as a result, the self-sustained operation mode can be continued for a relatively long time, for example, at startup.

  A second characteristic configuration of the reforming apparatus according to the present invention includes: a selective oxidation unit that oxidizes and removes carbon monoxide contained in the hydrogen-containing gas in contact with an oxidation catalyst in the hydrogen-containing gas flow path; and the selective oxidation And a cooling part that cools the hydrogen-containing gas before being supplied to the part below the temperature of the oxidation catalyst layer.

The reforming apparatus according to the present invention controls the operation of the raw fuel supply amount adjusting means and the water supply amount adjusting means in the self-sustaining operation mode to increase the steam-carbon ratio compared to the rated operation of the fuel cell. Since the steam-to-carbon ratio is set to the self-sustained operation target steam ratio, a relatively large amount of water vapor is present in the hydrogen-containing gas discharged from the reforming section, and the hydrogen-containing gas is supplied to the selective oxidation section as it is. Then, there is a concern that the water vapor is condensed on the surface of the oxidation catalyst and the oxidation removal ability of carbon monoxide by the oxidation catalyst is reduced.
Therefore, according to the second characteristic configuration, the cooling unit is provided, and the hydrogen-containing gas before being supplied to the selective oxidation unit by the cooling unit is cooled below the temperature of the oxidation catalyst layer of the selective oxidation unit. The dew point of the hydrogen-containing gas supplied to the selective oxidation unit is set to be equal to or lower than the temperature of the oxidation catalyst layer to prevent water vapor condensation on the surface of the oxidation catalyst, and to maintain a good oxidation removal ability of carbon monoxide by the oxidation catalyst. be able to. Therefore, the self-sustaining operation mode can be continued in a state where a hydrogen-containing gas having a very low carbon monoxide concentration is obtained. For example, the carbon monoxide concentration can be applied to the fuel electrode of the fuel cell even immediately after the self-sustaining operation mode is finished. A very low hydrogen-containing gas feed can be started.

  A third characteristic configuration of the reforming apparatus according to the present invention is included in the hydrogen-containing gas flow path, a shift unit that converts carbon monoxide contained in the hydrogen-containing gas into carbon dioxide, and the hydrogen-containing gas. A selective oxidation unit that oxidizes and removes carbon monoxide contained in carbon monoxide is provided, and the combustion unit, the reforming unit, the metamorphic unit, and the selective oxidation unit are adjacent to each other so that they can conduct heat. It is in the point where it is installed side by side.

  According to the third characteristic configuration, even when the combustion section, the reforming section, the transformation section, and the selective oxidation section are arranged side by side so that they can conduct heat with each other, they can operate independently. In the mode, the temperature of the reforming unit is suppressed from exceeding an appropriate range by reducing the heat generation amount in the combustion unit and further increasing the heat consumption in the steam generation unit. It can suppress that the temperature of the said selective oxidation part also exceeds an appropriate range, and can maintain the processing capability of the said conversion part and the carbon monoxide of the said selective oxidation part to a favorable thing. Accordingly, the self-sustaining operation mode can be continued in a state where a hydrogen-containing gas having a very low carbon monoxide concentration is obtained. For example, the carbon monoxide concentration is extremely high at the fuel electrode of the fuel cell even immediately after the self-sustaining operation mode is finished. The supply of a low hydrogen-containing gas can be started.

Hereinafter, a first embodiment of the present invention will be described with reference to the drawings.
A fuel cell system 100 shown in FIG. 1 includes a reformer 10 that reforms a hydrocarbon-based raw fuel G such as natural gas, liquefied petroleum gas, naphtha, kerosene, etc., into a hydrogen-containing gas H containing hydrogen as a main component. And a fuel cell 50 that generates electric power by reacting the hydrogen-containing gas H and air A.

  The reformer 10 includes a combustion unit 21 that combusts a fuel for heating, and a reformer that generates the hydrogen-containing gas H by reforming the raw fuel G with steam S while being heated by the combustion gas E of the combustion unit 21. And a steam generation unit 22 that generates water vapor S supplied to the reforming unit 12 by heating the water W with the combustion gas E after heating the reforming unit 12 of the combustion unit 21. The hydrogen-containing gas H generated in the reforming unit 12 is supplied to the fuel electrode 51 of the fuel cell 50 through the hydrogen-containing gas channel 26, while the hydrogen discharged from the fuel electrode 51 of the fuel cell 50 remains. The fuel offgas O is supplied to the combustion section 21 as the heating fuel through the fuel offgas passage 29 and burned.

  Further, the reformer 10 includes a desulfurization unit 11 that desulfurizes the raw fuel G before being supplied to the reforming unit 12, and carbon monoxide in the hydrogen-containing gas H discharged from the reforming unit 12. A shift section 13 for converting to carbon and a selective oxidation section 14 for oxidizing and removing carbon monoxide in the hydrogen-containing gas H discharged from the shift section 13 are provided.

  The desulfurization part 11 hydrogenates the sulfur compound in the raw fuel G by the catalytic action of the hydrodesulfurization catalyst at a desulfurization treatment temperature in the range of 200 to 350 ° C., for example, and adsorbs the hydride to zinc oxide for desulfurization. It is configured as follows. Incidentally, the desulfurization reaction in the desulfurization part 11 is an exothermic reaction. Further, the desulfurization section 11 is filled with a granular molded body such as nickel-molybdenum or chromium-molybdenum as the hydrodesulfurization catalyst.

  The reforming unit 12 is supplied with the raw fuel G after desulfurization from the desulfurization unit 11, and, for example, at a reforming treatment temperature in the range of 600 to 750 ° C., the hydrocarbon ( For example, methane) and the steam S supplied from the steam generation unit 22 are reformed as shown in the following reaction formula [Chemical Formula 1] to generate a hydrogen-containing gas H containing hydrogen and carbon monoxide. It is configured. Incidentally, the reforming reaction in the reforming unit 12 is an endothermic reaction. The reforming section 12 is filled with a large number of ceramic porous particles carrying ruthenium, nickel, platinum or the like as the reforming catalyst.

[Chemical 1]
CH ₄ + H ₂ O → CO + 3H ₂

  Combustion unit 21 is configured to combust a heating fuel such as raw fuel G and fuel off-gas O, which will be described later, with combustion air A, and reforming unit 12 is heated by combustion gas E. The steam generation unit 22 is heated by the combustion gas E after the reforming unit 12 is heated.

The water vapor generation unit 22 is configured to generate water vapor S by heating the supplied water W with the combustion gas E supplied from the combustion unit 21. The steam is supplied to the raw fuel G before being supplied to the reforming unit 12.
Further, the water W supplied to the steam generating unit 22 is preheated in the heat exchanging unit 16 by heat exchange with the hydrogen-containing gas H before being discharged from the shift unit 13 to be described later and supplied to the selective oxidation unit 14. It is configured as follows.

  The shift section 13 is supplied with the hydrogen-containing gas H discharged from the reforming section 12, for example, at a shift treatment temperature in the range of 200 to 300 ° C., carbon monoxide in the hydrogen-containing gas H, and also a hydrogen-containing gas. The water vapor in H is converted by the catalytic action of the shift catalyst as shown in the following reaction formula [Chemical Formula 2] to convert the carbon monoxide gas into carbon dioxide gas. Incidentally, the metamorphic reaction in the metamorphic part 13 is an exothermic reaction. The shift section 13 is filled with an iron / chromium-based or copper / zinc-based granular molded body as the shift catalyst.

[Chemical 2]
CO + H ₂ O → CO ₂ + H ₂

  The selective oxidation unit 14 is supplied with the hydrogen-containing gas H discharged from the shift conversion unit 13, and, for example, the carbon monoxide in the hydrogen-containing gas H is converted into a selective oxidation catalyst at an oxidation treatment temperature in the range of 80 to 150 ° C. As shown in the following reaction formula [Chemical Formula 3] by catalytic action, it is configured to selectively remove carbon monoxide. Incidentally, the oxidation reaction in the selective oxidation unit 14 is an exothermic reaction. The selective oxidation unit 14 is filled with a large number of ceramic porous particles on which a noble metal such as platinum, ruthenium, or rhodium is supported as the selective oxidation catalyst.

[Chemical formula 3]
2CO + O ₂ → 2CO ₂

  As described above, the hydrogen-containing gas H discharged from the selective oxidation unit 14 of the reformer 10 has a very low carbon monoxide concentration (for example, 10 ppm or less), and this hydrogen-containing gas H is the fuel cell 50. To the fuel electrode 51.

  Further, as shown in FIG. 2, the reformer 10 includes various processing units such as a combustion unit 21, a reforming unit 12, a conversion unit 13, a selective oxidation unit 14, and a desulfurization unit 11 and a steam generation unit 22. Adjacent ones are arranged side by side so that they can conduct heat.

  That is, in the reformer 10, the reforming section 12 that needs to be maintained at the highest temperature is disposed adjacent to the combustion section 21, and the selective oxidation section 14 that needs to be maintained at the lowest temperature is the most combustion section. Further, desulfurization that is disposed at a position far from 21 and needs to be maintained between the reforming unit 12 and the selective oxidation unit 14 at a temperature between the temperatures of the reforming unit 12 and the selective oxidation unit 14. The part 11 and the transformation part 14 are arranged from the reforming part 12 side in descending order of temperature, and the steam generating part 22 is arranged on the opposite side of the combustion part 21 from the reforming part 12 side with a heat insulating material interposed therebetween. Has been.

  Then, by appropriately setting the heat transfer state between the processing units and the heat release state by the fan 62 on the selective oxidation unit 14 side, the combustion amount of the combustion unit 21 is adjusted without consuming excess energy. Thus, the other desulfurization unit 11, the shift conversion unit 13, the selective oxidation unit 14, and the steam generation unit 22 can be maintained at appropriate temperatures only by controlling the reforming unit 12 at an appropriate reforming treatment temperature.

  The various processing units in the reforming apparatus 10 can be configured in flat containers arranged in a stacked manner, or can be configured in a space between multiple cylindrical bodies. Moreover, you may provide various process parts separately, without arranging in parallel so that heat may be transmitted between adjacent things as mentioned above.

  The fuel cell 50 is a solid polymer type having a polymer membrane as an electrolyte 53, hydrogen in the hydrogen-containing gas H supplied from the reformer 10 to the fuel electrode 51, and air A supplied to the air electrode 52. It is configured to generate electricity by an electrochemical reaction with oxygen therein.

  Further, in the fuel off-gas O discharged from the fuel electrode 51 of the fuel cell 50, hydrogen that has not been consumed in the fuel electrode 51 remains, so that the fuel off-gas O is heated in the combustion chamber 21. It is supplied as fuel and burns.

  The reformer 10 is provided with a raw fuel supply amount adjusting valve 24 as a raw fuel supply amount adjusting means capable of adjusting the supply amount of the raw fuel G to the reforming unit 12. The supply amount of the raw fuel G is adjusted by the raw fuel supply amount adjustment valve 24, thereby adjusting the supply amount of the hydrogen-containing gas H to the fuel electrode 51 of the fuel cell 50.

  Further, the reformer 10 is provided with a water supply amount adjustment valve 25 as water supply amount adjustment means capable of adjusting the supply amount of water W to the steam generation unit 22. And the supply amount of the water vapor | steam S by this water supply amount adjustment valve 25 is adjusted, and the supply amount of the water vapor | steam S to the reforming part 12 is adjusted.

  Further, a control device 60 composed of a computer is provided as a control means for controlling the operation of the reforming device 10, and this control device 60 supplies the hydrogen-containing gas H to the fuel electrode 51 of the fuel cell 50 to generate electric power. In the normal operation mode, the operation of the raw fuel supply amount adjustment valve 24 and the water supply amount adjustment valve 25 is controlled to control the hydrogen content in the fuel electrode 51 of the fuel cell 50. The supply amount of the gas H is set to an appropriate value that matches the output of the fuel cell 50, and the water W to the steam generation unit 22 with respect to the supply amount of the raw fuel G corresponding to the steam-carbon ratio in the reforming unit 12 is set. The ratio of the supply amount (hereinafter referred to as the water supply amount ratio) is set to an appropriate value suitable for the steam reforming reaction.

Incidentally, the control device 60 determines the target raw fuel supply amount to the reformer 12 based on the target output of the fuel cell 50 in the normal operation mode, and for example, detects the actual raw fuel detected by a flow sensor (not shown). By controlling the opening of the raw fuel supply amount adjustment valve 24 so that the raw fuel supply amount becomes the target raw fuel supply amount, the raw fuel supply amount to the reformer 12 matches the output of the fuel cell 50. The target raw fuel supply amount is set. That is, in the normal operation mode, the raw fuel supply amount is set so as to increase as the target output of the fuel cell 50 increases, and during the rated operation where the output of the fuel cell 50 is maximized, the raw fuel supply amount is the maximum. Is set to the rated target raw fuel supply amount.
The opening degree of the raw fuel supply amount adjustment valve 24 is controlled based on the correlation between the opening degree of the raw fuel supply amount adjustment valve 24 and the raw fuel supply amount, and the raw fuel supply amount is set to the target raw fuel supply amount. It does not matter if set to

Further, in the normal operation mode, the control device 60 determines a target water supply amount so as to achieve an appropriate target steam / carbon ratio in the reforming unit 12, for example, actual water detected by a flow sensor (not shown). The water supply amount is set to the target water supply amount by controlling the opening of the water supply amount adjustment valve 25 so that the ratio of the supply amount to the target raw fuel supply amount becomes the target steam-carbon ratio. It is configured as follows. In other words, the water supply amount is set to a water supply amount that maintains a substantially constant rated target steam-carbon ratio during the rated operation of the fuel cell 50 and all the operations in which the output is reduced from the rated operation.
The water supply amount adjustment valve 25 may be controlled based on the correlation between the water supply amount adjustment valve 25 and the water supply amount, and the water supply amount may be set to the target water supply amount. I do not care.

  The reformer 10 configured as described above cannot obtain the hydrogen-containing gas H having a low carbon monoxide concentration because the temperature of the reformer 10 is not stable, At the time of start-up when the hydrogen-containing gas H is not ready to be received, the entire amount of the hydrogen-containing gas H generated in the reforming unit 12 is supplied to the combustion unit 21 without being supplied to the fuel electrode 51 of the fuel cell 50. The fuel cell 50 is stopped while being supplied and combusted, and the generation of the hydrogen-containing gas H is continued. The detailed configuration will be described below.

  The reformer 10 is provided with a bypass passage 28 that connects the hydrogen-containing gas passage 26 and the fuel off-gas passage 29, and further, the hydrogen-containing gas H flowing through the hydrogen-containing gas passage 26 is supplied to the fuel cell. The supply state supplied to the fuel electrode 51 of the fuel cell 50 and the hydrogen-containing gas H are supplied to the combustion unit 21 as fuel for heating through the bypass passage 28 and the fuel offgas passage 29 by bypassing the fuel electrode 51 of the fuel cell 50. As a switching means capable of switching between the bypass state, three-way switching for switching the flow direction of the hydrogen-containing gas H in the hydrogen-containing gas channel 26 between the direction toward the fuel electrode 51 of the fuel cell 10 and the direction toward the bypass channel 28 side. A valve 27 is provided.

  Further, the control device 60 has a self-sustained operation mode other than the normal operation mode, and in this self-sustained operation mode, the three-way switching valve 27 is switched to the bypass state to flow the hydrogen-containing gas H in the hydrogen-containing gas flow path 26. Is switched to the direction toward the bypass flow path 28, and the opening amounts of the raw fuel supply amount adjustment valve 24 and the water supply amount adjustment valve 25 are controlled to reduce the raw fuel supply amount from the rated target raw fuel supply amount. The fuel cell 50 is stopped at a stand-alone operation target steam / carbon ratio in which the steam / carbon ratio is increased from the rated target steam / carbon ratio and the self-sustained operation target raw fuel supply amount for autonomous operation Thus, the generation of the hydrogen-containing gas H by the reformer 60 is continued.

  That is, in the self-sustained operation mode, by setting the raw fuel supply amount to the self-sustained operation target raw fuel supply amount, the calorific value in the combustion section 21 is made relatively low, and the steam-carbon ratio is set to the self-sustained operation target steam. -By setting the carbon ratio, the heat consumption for heating water into steam in the steam generation section 22 and the heat consumption for raising the steam temperature to the reforming temperature in the reforming section 12 As a result, the self-sustained operation mode can be continued for a relatively long time while suppressing the temperature of the reforming unit 12 and the like of the reformer 10 from exceeding an appropriate range.

Furthermore, the reformer 10 can be provided with a cooling unit 18 that cools the hydrogen-containing gas H supplied from the heat exchanger 16 to the selective oxidation unit 14 to a temperature equal to or lower than the temperature of the oxidation catalyst layer in the selective oxidation unit 14. By setting the dew point of the hydrogen-containing gas H supplied to the selective oxidation unit 14 by the cooling unit 18 to be equal to or lower than the temperature of the oxidation catalyst layer, condensation of water vapor on the oxidation catalyst surface in the selective oxidation unit 14 can be prevented.
Further, the condensed water generated by being cooled by the cooling unit 18 is discharged to the outside through the gas-liquid separation unit 19.
If there is no problem even if the dew point of the hydrogen-containing gas H is not lowered, the cooling unit 18 and the gas-liquid separation unit 19 can be omitted.

Schematic configuration diagram of fuel cell system Diagram explaining heat transfer state of reformer

Explanation of symbols

10: reformer 11: desulfurization unit 12: reforming unit 13: shifter unit 14: selective oxidation unit 18: cooling unit 19: gas-liquid separation unit 21: combustion unit 22: steam generation unit 24: raw fuel supply amount adjustment valve (Raw fuel supply amount adjustment means)
25: Water supply amount adjustment valve (water supply amount adjustment means)
26: Hydrogen-containing gas flow path 27: Three-way switching valve (switching means)
28: Bypass channel 29: Fuel off-gas channel 50: Fuel cell 51: Fuel electrode 60: Control device (control means)
A: Air E: Combustion gas G: Raw fuel H: Hydrogen-containing gas O: Fuel off-gas S: Water vapor W: Water

Claims (3)

A combustion section for combusting a heating fuel; a reforming section for generating a hydrogen-containing gas containing hydrogen as a main component by reforming a hydrocarbon-based raw fuel with steam while heating with a combustion gas of the combustion section; A water vapor generating unit that generates water vapor that is supplied to the reforming unit by heating water with the combustion gas after heating the reforming unit of the combustion unit, and supplying the hydrogen-containing gas to the fuel electrode of the fuel cell Switching means capable of switching between a supply state to be performed and a bypass state in which the hydrogen-containing gas is bypassed through the fuel electrode of the fuel cell and supplied to the combustion unit as the heating fuel, and raw fuel supply to the reforming unit A raw fuel supply amount adjusting means capable of adjusting the amount, a water supply amount adjusting means capable of adjusting a water supply amount to the water vapor generating unit, and a normal operation of operating the fuel cell by switching the switching means to the supply state. Driving mode and Serial and the total amount of the hydrogen-containing gas generated in the switching and the reforming section in the bypass state the switching means is combusted in the combustion section, it continues to generate the hydrogen-containing gas in a stopped state of the fuel cell A reforming apparatus comprising a control means having a self-sustaining operation mode,
In the self-sustained operation mode, the control means sets the raw fuel supply amount as a self-sustained operation target raw fuel supply amount for self-sustained operation, which is less than a rated target raw fuel supply amount when the fuel cell is rated-operated. In addition, a self-sustained operation target for self-sustaining operation in which a steam-carbon ratio, which is a ratio of the water supply amount to the raw fuel supply amount, is increased from a rated target steam-carbon ratio when the fuel cell is rated-operated. A reformer for controlling operations of the raw fuel supply amount adjusting means and the water supply amount adjusting means so as to obtain a steam-carbon ratio.   A selective oxidation unit for contacting and oxidizing the carbon monoxide contained in the hydrogen-containing gas with an oxidation catalyst, and a hydrogen-containing gas before being supplied to the selective oxidation unit in the hydrogen-containing gas flow path The reformer according to claim 1, further comprising a cooling unit that cools to a temperature below the temperature of the layer.   Selection for converting the carbon monoxide contained in the hydrogen-containing gas into carbon dioxide in the hydrogen-containing gas flow path and oxidizing and removing carbon monoxide contained in the carbon monoxide contained in the hydrogen-containing gas The modification according to claim 1 or 2, further comprising an oxidation unit, wherein the combustion unit, the reforming unit, the transformation unit, and the selective oxidation unit are arranged side by side so as to be able to conduct heat with each other. Quality equipment.

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