JP2014218408A - Hydrogen generator and fuel cell system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hydrogen generator capable of dealing with a problem that occurs in a CO detector when hydrogen-containing gas is burned by a combustor and exhausted more appropriately than conventional generators.SOLUTION: A hydrogen generator 100 comprises: a reformer 1 which creates hydrogen-containing gas by using raw material; a combustor 2 which burns hydrogen-containing gas; a first exhaust gas flow path 8 in which exhaust gas from the combustor 2 flows; a branch path 11 provided on the first exhaust gas flow path 8; a CO detector 9 provided for the branch path 11; a breaker 10 which breaks inflow of exhaust gas to the branch path 11; and a controller 12 which breaks the breaker 10 in a part of a period in which exhaust gas flows in the first exhaust gas flow path 8.

Description

  The present invention relates to a hydrogen generator and a fuel cell system.

  Since an infrastructure for supplying hydrogen has not been prepared, a system using hydrogen as a fuel, such as a fuel cell system, is usually provided with a hydrogen generation device including a reformer. In addition, the hydrogen generator is provided with a combustor that heats the reformer by burning the hydrogen-containing gas generated by the reformer. Therefore, a hydrogen generator in which a CO detector that detects carbon monoxide (CO) in the exhaust gas of the combustor is disposed on the exhaust gas flow path of the combustor has been proposed (see, for example, Patent Document 1).

JP 2006-213566 A

  However, the problem that occurs in the CO detector when the hydrogen-containing gas is burned and discharged by the combustor has not been studied conventionally.

  One aspect of the present invention has been made in view of such circumstances, and can appropriately deal with a problem that occurs in a CO detector when a hydrogen-containing gas is burned and discharged by a combustor. An object is to provide a hydrogen generator and a fuel cell system.

  A hydrogen generator according to an aspect of the present invention includes a reformer that generates a hydrogen-containing gas using a raw material, a combustor that burns the hydrogen-containing gas, and a first exhaust gas flow through which exhaust gas from the combustor flows. A branch path provided on the first exhaust gas flow path, a CO detector provided in the branch path, a circuit breaker for blocking inflow of the exhaust gas to the branch path, and the first exhaust gas A controller that shuts off the circuit breaker in a part of a period in which the exhaust gas flows through the flow path.

  A fuel cell system according to one embodiment of the present invention includes the above-described hydrogen generation device and a fuel cell that generates power using a hydrogen-containing gas supplied from the hydrogen generation device.

  The hydrogen generator and the fuel cell system according to one embodiment of the present invention can more appropriately cope with the problem that occurs in the CO detector when the hydrogen-containing gas is burned and discharged in the combustor than in the past.

FIG. 1 is a diagram illustrating an example of a hydrogen generator according to the first embodiment. FIG. 2 is a flowchart showing an example of the operation of the hydrogen generator of the first embodiment. FIG. 3 is a flowchart showing an example of the operation of the hydrogen generator of the first example of the second embodiment. FIG. 4 is a flowchart showing an example of the operation of the hydrogen generator of the second example of the second embodiment. FIG. 5 is a flowchart showing an example of the operation of the hydrogen generator of the third example of the second embodiment. FIG. 6 is a diagram illustrating an example of a hydrogen generation apparatus according to a fourth example of the second embodiment. FIG. 7 is a flowchart showing an example of the operation of the hydrogen generator of the fourth example of the second embodiment. FIG. 8 is a diagram illustrating an example of a hydrogen generator according to the third embodiment. FIG. 9 is a flowchart showing an example of the operation of the hydrogen generator of the fourth embodiment. FIG. 10 is a diagram illustrating an example of the fuel cell system according to the fifth embodiment.

(First embodiment)
The present inventors diligently studied the problem that occurs in the CO detector when the hydrogen-containing gas is burned and discharged by the combustor, and obtained the following knowledge.

  As a chemical sensor that is an example of a CO detector, an n-type semiconductor oxide sensitized by adding a trace amount of a metal element such as a noble metal, for example, a sintered body of tin oxide, and this semiconductor is in contact with a combustible gas. Gas sensor (semiconductor type sensor) that detects flammable gas using the characteristic that the electric conductivity changes when it is applied, and a carrier is attached to a thin platinum wire, with or without a noble metal There is known a gas sensor (contact combustion sensor) that detects a difference in heat generated when a combustible gas is brought into contact with this element and undergoes a catalytic oxidation reaction using a pair of comparison elements. Yes.

  When such a CO detector is used in a hydrogen generator, hydrogen contained in the exhaust gas from the combustor can be exposed to the CO detector through the exhaust gas flow path if the hydrogen-containing gas cannot be properly combusted in the combustor. There is sex. Thereby, there exists a problem that the electrode and catalyst which bear the central function of a chemical sensor deteriorate with time. Note that this deterioration is due to, for example, that the catalyst is reduced by hydrogen present in the exhaust gas, and the detection reaction in the CO detector is hindered.

  Therefore, the hydrogen generator of the first embodiment includes a reformer that generates a hydrogen-containing gas using raw materials, a combustor that burns the hydrogen-containing gas, and a first exhaust gas flow path through which exhaust gas from the combustor flows. A branch path provided on the first exhaust gas flow path, a CO detector provided in the branch path, a circuit breaker for blocking inflow of the exhaust gas to the branch path, and exhaust gas in the first exhaust gas flow path And a controller that shuts off the circuit breaker during a part of the flowing period.

  With this configuration, the problem that occurs in the CO detector when the hydrogen-containing gas is burned and discharged by the combustor can be more appropriately addressed than in the past. As described above, the controller shuts off the circuit breaker during a part of the period in which the exhaust gas flows through the first exhaust gas passage. For this reason, since the possibility that the CO detector is exposed to hydrogen gas that promotes the deterioration of the CO detector is reduced as compared with the conventional example in which the CO detector is disposed on the first exhaust gas flow path, the CO detector The possibility of deterioration due to hydrogen exposure is reduced.

[Device configuration]
FIG. 1 is a diagram illustrating an example of a hydrogen generator according to the first embodiment.

  In the example shown in FIG. 1, the hydrogen generator 100 of the present embodiment includes a reformer 1, a combustor 2, a first exhaust gas channel 8, a CO detector 9, a circuit breaker 10, and a branch channel. 11 and a controller 12.

  The reformer 1 produces | generates hydrogen containing gas using a raw material. Specifically, in the reformer 1, the raw material undergoes a reforming reaction to generate a hydrogen-containing gas. The reforming reaction may take any form, and examples thereof include a steam reforming reaction, an autothermal reaction, and a partial oxidation reaction. Although not shown in FIG. 1, equipment required for each reforming reaction is provided as appropriate. For example, if the reforming reaction is a steam reforming reaction or an autothermal reaction, in addition to the combustor 2, an evaporator that generates steam and a water supplier that supplies water to the evaporator are provided. If the reforming reaction is an autothermal reaction, the hydrogen generator 100 is further provided with an air supply device that supplies air to the reformer.

  The raw material includes an organic compound composed of at least carbon and hydrogen such as city gas, natural gas, and LPG mainly composed of methane. The raw material is supplied from a raw material supply source (not shown). The raw material supply source has a predetermined supply pressure, and examples thereof include a raw material cylinder and a raw material infrastructure.

  The combustor 2 burns the hydrogen-containing gas. A hydrogen-containing gas is supplied from the reformer 1 to the combustor 2 and air is supplied from an air supply device (not shown). The reformer 1 is heated by the combustion of the hydrogen-containing gas and air. The fuel of the combustor 2 may be any fuel. For example, a hydrogen-containing gas discharged from the reformer 1 may be used as the combustion fuel. The combustor 2 may have any configuration as long as it can combust the hydrogen-containing gas. For example, the combustor 2 may be a premixed combustion burner that supplies hydrogen-containing gas and air mixed in advance in the outside, or may be a diffusion combustion burner that supplies these separately and mixes them inside. Absent.

  Although not shown in FIG. 1, equipment necessary for the combustor 2 is provided as appropriate. For example, the combustor 2 is provided with an igniter. Examples of the igniter include an ignition device including a high-voltage electrode disposed at a position where a spark can be generated between the igniter and the ground electrode, but is not limited to this method. The combustor 2 is provided with a flame detector. Examples of the flame detector include a flame rod that measures an ionization current value generated when the hydrogen-containing gas is burned, or a thermocouple that detects the temperature of the flame, but is not limited to this method.

  The first exhaust gas channel 8 is a channel through which the exhaust gas from the combustor 2 flows. The first exhaust gas channel 8 is connected to the combustor 2, and the combustion exhaust gas generated in the combustor 2 flows through the first exhaust gas channel 8 and is released to the atmosphere.

  The branch path 11 is provided on the first exhaust gas flow path 8. That is, a branch path 11 that branches from the first exhaust gas flow path 8 is formed in the middle of the first exhaust gas flow path 8. In the present embodiment, the branch path 11 is configured so that the exhaust gas traveling toward the CO detector 9 reaches the CO detector 9 and then returns to the first exhaust gas flow path 8 through the branch path 11 again. Although the opposing flow path is configured, the present invention is not limited to this. For example, the branch path may be configured such that the exhaust gas that has contacted the CO detector 9 escapes downstream of the CO detector 9 and is exhausted.

  The CO detector 9 is provided in the branch path 11. The CO detector 9 may have any configuration as long as it can detect CO in the exhaust gas flowing through the first exhaust gas passage 8. The CO detector 9 may be, for example, a contact combustion type CO detector or a semiconductor type CO detector.

  The circuit breaker 10 blocks the inflow of exhaust gas to the branch path 11. That is, if the flow of the exhaust gas from the first gas flow path 8 is blocked by the circuit breaker 10, the possibility that the CO detector 9 is exposed to the exhaust gas flowing through the first exhaust gas flow path 8 is reduced. The circuit breaker 10 may have any configuration as long as it can block the flow of exhaust gas from the first exhaust gas flow path 8 to the branch path 11. The circuit breaker 10 may be an on-off valve that opens and closes the branch path 11, for example.

  The controller 12 shuts off the circuit breaker 10 during a part of the period in which the exhaust gas flows through the first exhaust gas flow path 8. The controller 12 may have any configuration as long as it has a control function. The controller 12 includes, for example, an arithmetic processing unit and a storage unit that stores a control program. Examples of the arithmetic processing unit include an MPU and a CPU. An example of the storage unit is a memory. The controller 12 may be composed of a single controller that performs centralized control, or may be composed of a plurality of controllers that perform distributed control in cooperation with each other.

[Operation]
FIG. 2 is a flowchart showing an example of the operation of the hydrogen generator of the first embodiment. The following operations are controlled by the controller 12.

  In the example shown in FIG. 2, when it is determined in step S101A that the predetermined period of the period during which the exhaust gas from the combustor 2 flows, the circuit breaker 10 is blocked (step S102).

  The predetermined period is a part of the period in which the exhaust gas from the combustor 2 flows, and is appropriately set depending on the configuration, operation, and the like of the hydrogen generator.

  As described above, during the period in which the circuit breaker 10 is cut off, even if the exhaust gas from the combustor 2 contains hydrogen, the CO detector 9 is not exposed to hydrogen, so the CO detector is placed on the first exhaust gas channel. The CO detector 9 can reduce the possibility of deterioration due to hydrogen exposure as compared with the conventional arrangement in which is disposed.

(Second Embodiment)
The hydrogen generator of 2nd Embodiment is a hydrogen generator of 1st Embodiment, A controller interrupts | blocks a circuit breaker, when hydrogen may be contained in the exhaust gas from a combustor.

  With this configuration, it is possible to reduce the possibility that the CO detector will deteriorate due to hydrogen exposure, as compared with the hydrogen generator of the first embodiment.

  In addition, when there is no possibility that hydrogen is contained in the exhaust gas from the combustor, the circuit breaker may be opened. Thereby, CO in exhaust gas can be appropriately detected with a CO detector.

  Hereinafter, specific examples of the hydrogen generator of this embodiment will be described in the following examples.

(First embodiment)
The hydrogen generator of the first example of the second embodiment is the hydrogen generator of the second embodiment. The controller shuts off the circuit breaker when starting the production of the hydrogen-containing gas in the reformer.

  When the production of the hydrogen-containing gas is started in the reformer, steam is supplied to the reformer. At this time, a gas corresponding to the volume of water evaporation supplied to the reformer is pushed out from the reformer to the combustor. In this case, the combustion state of the combustor changes. At this time, for example, if the gas pushed out to the combustor cannot be combusted by the combustor due to extinguishing of the combustor, hydrogen may be contained in the exhaust gas from the combustor. However, in this embodiment, when the production of the hydrogen-containing gas is started in the reformer, the circuit breaker is cut off. Therefore, compared to the case where the circuit breaker is not cut off when the production of the hydrogen-containing gas is started in the reformer. The possibility of deterioration of the CO detector due to hydrogen exposure is reduced.

  The hydrogen generator of this example may be configured similarly to the hydrogen generator of the second embodiment, except for the above features.

[Device configuration]
The hydrogen generator 100 of the present embodiment has the same configuration as that of FIG. 1, and includes a reformer 1, a combustor 2, a first exhaust gas flow path 8, a CO detector 9, a circuit breaker 10, A branch path 11 and a controller 12 are provided. Since the configuration is the same as that of the first embodiment, description thereof is omitted.

[Operation]
FIG. 3 is a flowchart showing an example of the operation of the hydrogen generator of the first example of the second embodiment. The following operations are controlled by the controller 12.

  In the example shown in FIG. 3, it is determined in step S101B whether or not the generation of the hydrogen-containing gas is started in the reformer 1. For example, when generation of hydrogen-containing gas is started in the reformer 1, when steam reforming is performed in the reformer 1, supply of steam to the reformer 1 is started. In this case, as described above, hydrogen may be contained in the exhaust gas from the combustor 2.

  Therefore, when the generation of the hydrogen-containing gas is started in the reformer 1 in step S101B, the circuit breaker 10 is shut off (step S102).

  In addition, after the circuit breaker 10 is interrupted, the circuit breaker 10 may be opened at a predetermined timing. Here, the predetermined timing is a timing at which it is assumed that the possibility that hydrogen is contained in the exhaust gas from the combustor 2 is reduced, and is set as appropriate depending on the configuration and operation of the hydrogen generator.

  As described above, when the generation of the hydrogen-containing gas in the reformer 1 is started, the breaker 10 is shut off, so that the possibility of deterioration of the CO detector 9 due to hydrogen exposure is reduced.

(Second embodiment)
The hydrogen generator of 2nd Example of 2nd Embodiment is a hydrogen generator of 2nd Embodiment. When a controller switches the fuel of a combustor from a raw material to hydrogen-containing gas, it interrupts | blocks a circuit breaker.

  When the fuel of the combustor is switched from the raw material to the hydrogen-containing gas, the combustion state of the combustor changes. At this time, for example, if gas cannot be combusted in the combustor due to extinguishing of the combustor or the like, hydrogen may be contained in the exhaust gas from the combustor. However, in this embodiment, when the combustor fuel is switched from the raw material to the hydrogen-containing gas, the circuit breaker is shut off, so compared to the case where the circuit breaker is not shut off when the combustor fuel is switched from the raw material to the hydrogen-containing gas. The possibility of deterioration of the CO detector due to hydrogen exposure is reduced.

  The hydrogen generator of this example may be configured similarly to the hydrogen generator of the second embodiment, except for the above features.

[Device configuration]
The hydrogen generator 100 of the present embodiment has the same configuration as that of FIG. 1, and includes a reformer 1, a combustor 2, a first exhaust gas flow path 8, a CO detector 9, a circuit breaker 10, A branch path 11 and a controller 12 are provided. Since the configuration is the same as that of the first embodiment, description thereof is omitted.

[Operation]
FIG. 4 is a flowchart showing an example of the operation of the hydrogen generator of the second example of the second embodiment. The following operations are controlled by the controller 12.

  In the example shown in FIG. 4, it is determined in step S101C whether or not the fuel in the combustor 2 is switched from the raw material to the hydrogen-containing gas. As described above, when the fuel of the combustor 2 is switched from the raw material to the hydrogen-containing gas, there is a possibility that the exhaust gas from the combustor 2 contains hydrogen.

  Therefore, when the fuel of the combustor 2 is switched from the raw material to the hydrogen-containing gas in step S101C, the circuit breaker 10 is interrupted (step S102).

  In addition, after the circuit breaker 10 is interrupted, the circuit breaker 10 may be opened at a predetermined timing. Here, the predetermined timing is a timing at which it is assumed that the possibility that hydrogen is contained in the exhaust gas from the combustor 2 is reduced, and is set as appropriate depending on the configuration and operation of the hydrogen generator.

  As described above, when the fuel of the combustor 2 is switched from the raw material to the hydrogen-containing gas, the circuit breaker 10 is shut off, so that the possibility of deterioration of the CO detector 9 due to hydrogen exposure is reduced.

(Third embodiment)
The hydrogen generation apparatus according to the third example of the first embodiment is the hydrogen generation apparatus according to any one of the second embodiment and the first example-second example of the second embodiment. After the fire extinguishing, the circuit breaker is shut off for at least part of the period in which the exhaust gas flows through the first exhaust gas passage.

  When fire extinguishing of the combustor occurs, the exhaust gas flowing through the first exhaust gas passage becomes unburned gas. Then, hydrogen is contained in the unburned gas from the combustor. Then, after a certain period of time has elapsed from when the combustor is extinguished, such unburned gas reaches the CO detector. However, in this embodiment, the circuit breaker is interrupted during at least part of the period in which the exhaust gas flows through the first exhaust gas flow path after the combustor is extinguished, so that the circuit breaker is not interrupted after the combustor is extinguished. The possibility of deterioration of the CO detector due to hydrogen exposure is reduced.

  The hydrogen generator of this example may be configured similarly to the hydrogen generator of any one of the second embodiment and the first to second examples of the second embodiment, except for the above characteristics.

[Device configuration]
The hydrogen generator 100 of the present embodiment has the same configuration as that of FIG. 1, and includes a reformer 1, a combustor 2, a first exhaust gas flow path 8, a CO detector 9, a circuit breaker 10, A branch path 11 and a controller 12 are provided. Since the configuration is the same as that of the first embodiment, description thereof is omitted.

[Operation]
FIG. 5 is a flowchart showing an example of the operation of the hydrogen generator of the third example of the second embodiment. The following operations are controlled by the controller 12.

  In the example shown in FIG. 5, it is determined in step S101D whether or not the combustor 2 has been extinguished. As described above, when fire extinguishing of the combustor 2 occurs, hydrogen is included in the unburned gas from the combustor 2.

  Therefore, when extinction of the combustor 2 occurs in step S101D, the circuit breaker 10 is interrupted during at least a part of the period in which the exhaust gas flows through the first exhaust gas passage 8 after the combustion of the combustor 2 (step S102). . When a certain period of time has elapsed from when the combustor 2 is extinguished, unburned gas from the combustor 2 reaches the CO detector. Therefore, for example, after the fire of the combustor 2, the circuit breaker 10 is interrupted at an appropriate time before the predetermined time has elapsed. The certain time can be calculated based on the capacity of the flow path from the outlet of the combustor 2 to the CO detector 9 and the flow rate of unburned gas.

  In addition, after the circuit breaker 10 is interrupted, the circuit breaker 10 may be opened at a predetermined timing. Here, the predetermined timing is a timing at which it is assumed that the possibility that hydrogen is contained in the exhaust gas from the combustor 2 is reduced, and is set as appropriate depending on the configuration and operation of the hydrogen generator.

  As described above, after the fire of the combustor 2, the circuit breaker 10 is shut off at least during a period in which the exhaust gas flows through the first exhaust gas flow path 8, thereby reducing the possibility of deterioration of the CO detector 9 due to hydrogen exposure. To do.

(Fourth embodiment)
The hydrogen generator of the fourth example of the second embodiment is the hydrogen generator of any one of the second embodiment and the first to third examples of the second embodiment. The controller combines with the second exhaust gas flow path through which the exhaust gas of the external combustion device flows, and the controller shuts off the circuit breaker when the external combustion device starts combustion or stops combustion.

When the first exhaust gas passage of the combustor joins the second exhaust gas passage through which the exhaust gas of the external combustion device flows, the combustor when the external combustion device starts combustion or stops combustion As the back pressure of the combustion chamber changes, the combustion state of the combustor may change. At this time, for example, if gas cannot be combusted in the combustor due to extinguishing of the combustor or the like, hydrogen may be contained in the exhaust gas from the combustor. However, in this embodiment, when the external combustion apparatus starts combustion or stops combustion, the circuit breaker is cut off. Therefore, compared with the case where the circuit breaker is not cut off at the time of starting and stopping the combustion, the CO The possibility of deterioration of the detector due to hydrogen exposure is reduced.
The hydrogen generator of this example may be configured in the same manner as the hydrogen generator of any of the second embodiment and the first to third examples of the second embodiment, except for the above characteristics.

[Device configuration]
FIG. 6 is a diagram illustrating an example of a hydrogen generation apparatus according to a fourth example of the second embodiment.

  In the example shown in FIG. 6, the hydrogen generator 100 of the present embodiment includes a reformer 1, a combustor 2, a first exhaust gas channel 8, a CO detector 9, a circuit breaker 10, and a branch channel. 11, a controller 12, an external combustion device 15, and a second exhaust gas flow channel 16. Since the reformer 1, the combustor 2, the first exhaust gas flow path 8, the CO detector 9, the circuit breaker 10, the branch path 11, and the controller 12 are the same as those in the first embodiment, description thereof is omitted.

  The second exhaust gas channel 16 is a channel through which the exhaust gas of the external combustion device 15 flows. The second exhaust gas channel 16 is connected to the external combustion device 15, and the combustion exhaust gas generated by the external combustion device 15 flows through the second exhaust gas channel 16 and is released to the atmosphere. Further, the first exhaust gas flow path 8 is joined with the second exhaust gas flow path 16 through which the exhaust gas of the external combustion device 15 flows. Therefore, the combustion exhaust gas generated by the combustor 2 flows through the second exhaust gas flow channel 16 together with the combustion exhaust gas from the external combustion device 15 and is released to the atmosphere. In addition, as the external combustion apparatus 15, a boiler is illustrated, for example.

[Operation]
FIG. 7 is a flowchart showing an example of the operation of the hydrogen generator of the fourth example of the second embodiment. The following operations are controlled by the controller 12.

In the example shown in FIG. 7, it is determined in step S101E whether the external combustion apparatus 15 has started or stopped combustion. As described above, when the external combustion apparatus 15 starts combustion or stops combustion, there is a possibility that the exhaust gas from the combustor 2 contains hydrogen.
Therefore, when the combustion of the external combustion device 15 is started or stopped in step S101E, the circuit breaker 10 is interrupted (step S102).

  In addition, after the circuit breaker 10 is interrupted, the circuit breaker 10 may be opened at a predetermined timing. Here, the predetermined timing is a timing at which it is assumed that the possibility that hydrogen is contained in the exhaust gas from the combustor 2 is reduced, and is set as appropriate depending on the configuration and operation of the hydrogen generator.

  As described above, when the external combustion apparatus 15 starts combustion or stops combustion, the circuit breaker 10 is shut off, so that the possibility of deterioration of the CO detector 9 due to hydrogen exposure is reduced.

(Third embodiment)
The hydrogen generator of the third embodiment is the hydrogen generator of any one of the first embodiment, the second embodiment, and the first embodiment to the fourth embodiment of the second embodiment. The bypass channel bypasses the channel, and at least two circuit breakers are provided in the bypass channel, and the CO detector is provided in the bypass channel between the two circuit breakers.

  With this configuration, the problem that occurs in the CO detector when the hydrogen-containing gas is burned and discharged by the combustor can be more appropriately addressed than in the past. As described above, the controller shuts off the two circuit breakers during a part of the period in which the exhaust gas flows through the first exhaust gas passage. For this reason, since the possibility that the CO detector is exposed to hydrogen gas that promotes the deterioration of the CO detector is reduced as compared with the conventional example in which the CO detector is disposed on the first exhaust gas flow path, the CO detector The possibility of deterioration due to hydrogen exposure is reduced. In the present embodiment, the branch path is a bypass flow path that bypasses the first exhaust gas flow path, and a CO detector is provided in the bypass flow path. For this reason, since it can comprise so that exhaust gas may pass a CO detector using a bypass channel, exhaust gas can be easily led to a CO detector. For example, the diameter of the flow path can be made smaller and the circuit breaker can be made smaller than when the branch path is configured so that the downstream end is sealed and is not opened to the atmosphere.

  The hydrogen generator of this embodiment is configured in the same manner as the hydrogen generator of any of the first to fourth embodiments of the first embodiment, the second embodiment, and the second embodiment except for the above features. May be.

[Device configuration]
FIG. 8 is a diagram illustrating an example of a hydrogen generator according to the third embodiment.

  In the example shown in FIG. 8, the hydrogen generator 100 of the present embodiment includes a reformer 1, a combustor 2, a first exhaust gas flow path 8, a CO detector 9, a first circuit breaker 10A, A second circuit breaker 10B, a branch path 11A, and a controller 12 are provided. In addition, although illustration is abbreviate | omitted, the hydrogen generator 100 of this embodiment may further be provided with the external combustion apparatus 15 and the 2nd exhaust gas flow path 16, as FIG.

  Since the reformer 1, the combustor 2, the first exhaust gas flow path 8, the CO detector 9, and the controller 12 are the same as those in the first embodiment, the description thereof is omitted.

  The branch passage 11 </ b> A is a bypass passage 11 </ b> A that bypasses the first exhaust gas passage 8. That is, the bypass channel 11A is in the middle of the first exhaust gas channel 8, branches from the first gas channel 8 at the upstream end of the bypass channel 11A, and the first at the downstream end of the bypass channel 11A. The gas flow path 8 is configured to communicate with each other.

  The first circuit breaker 10A and the second circuit breaker 10B are provided in the bypass channel 11A. Moreover, the CO detector 9 is provided in the bypass flow path 11A between the first circuit breaker 10A and the second circuit breaker 10B.

  The first circuit breaker 10A may have any configuration as long as it can block the flow of exhaust gas from the first exhaust gas flow path 8 to the bypass flow path 11A. 10 A of 1st circuit breakers may be an on-off valve which opens and closes the bypass flow path 11A, for example.

  The second circuit breaker 10B may have any configuration as long as it can block the flow of exhaust gas from the bypass flow path 11A to the first exhaust gas flow path 8. The second circuit breaker 10B may be, for example, an on-off valve that opens and closes the bypass channel 11A.

  As described above, a part of the exhaust gas flowing through the first exhaust gas passage 8 passes through the bypass passage 11A. For this reason, exhaust gas can be easily guided to the CO detector 9 using the bypass flow path 11A.

[Operation]
About operation | movement, it replaces with interruption | blocking of the circuit breaker 10 of step S102, and cut | disconnects 1st circuit breaker 10A and 2nd circuit breaker 10B, 1st Embodiment, 2nd Embodiment, and 2nd Embodiment. The operation is the same as that of any one of the hydrogen generators in the first embodiment to the fourth embodiment. Therefore, detailed description is omitted.

(Fourth embodiment)
The hydrogen generator of the fourth embodiment includes a controller in the hydrogen generator of any one of the first embodiment, the second embodiment, the first example of the second embodiment-the fourth example, and the third embodiment. Opens the circuit breaker after the circuit breaker is shut off.

  With this configuration, since the circuit breaker is opened after the circuit breaker is shut off, CO in the exhaust gas can be appropriately detected by the CO detector after the circuit breaker is opened.

  The hydrogen generator of this embodiment is the hydrogen generator of any one of the first embodiment, the second embodiment, the first embodiment-fourth embodiment and the third embodiment of the second embodiment, except for the above features. You may comprise similarly.

[Device configuration]
The apparatus configuration of the hydrogen generator 100 according to the fourth embodiment is the same as that of any one of the hydrogen generators according to the first embodiment, the fourth example of the second embodiment, and the third embodiment, and thus the description thereof is omitted. .

[Operation]
FIG. 9 is a flowchart showing an example of the operation of the hydrogen generator of the fourth embodiment. The following operations are controlled by the controller 12.

  As shown in FIG. 9, step S103 is the next step following the circuit breaker 10 shut-off in step S102 of FIG. 2, FIG. 3, FIG. 4, FIG.

  In step S103, it is determined whether or not a predetermined time has elapsed after the circuit breaker 10 is shut off. Until the predetermined time elapses in step S103, the state where the circuit breaker 10 is interrupted is maintained. Then, when a predetermined time elapses after the circuit breaker 10 is disconnected, the circuit breaker 10 is opened (step S104).

  The predetermined time in step S103 is appropriately set depending on the configuration, operation, etc. of the hydrogen generator as the time when it is assumed that the possibility that hydrogen is contained in the exhaust gas from the combustor 2 is reduced. Specifically, for example, it can be set as follows.

  When the combustor 2 is extinguished, a stop time from when the combustor 2 is extinguished until the fuel supply to the combustor 2 is stopped is derived. The predetermined time in step S103 can be set based on the estimated passage time until the unburned gas discharged from the combustor 2 passes through the CO detector 9 during the stop time. The estimated passage time can be calculated based on the capacity of the flow path from the outlet of the combustor 2 to the CO detector 9 and the flow rate of the exhaust gas.

  In addition, when the hydrogen-containing gas generation in the reformer 1 is started, when the fuel of the combustor 2 is switched from the raw material to the hydrogen-containing gas, or when the external combustion device 5 starts or stops combustion, first combustion is performed. It is confirmed whether the flame of the vessel 2 is maintained. When it is confirmed that the flame of the combustor 2 is retained, it can be determined that the unburned gas is not discharged from the combustor 2 at least after the confirmation. Therefore, the predetermined time of step S103 can be set based on the estimated passage time until the gas discharged at the time of confirmation passes through the CO detector 9. The estimated passage time can be calculated based on the capacity of the flow path from the outlet of the combustor 2 to the CO detector 9 and the flow rate of the exhaust gas.

  In addition, step S103 which determines the timing which opens the circuit breaker 10 is an example, Comprising: It is not limited to this example. The determination method of the timing which opens the circuit breaker 10 may be determined based on other conditions instead of the elapsed time after the circuit breaker 10 is disconnected as in step S103.

(Fifth embodiment)
The fuel cell system according to the fifth embodiment is the first embodiment, the second embodiment, the first embodiment of the second embodiment-the fourth embodiment, the hydrogen generation of any of the third embodiment and the fourth embodiment. And a fuel cell that generates power using a hydrogen-containing gas supplied from the hydrogen generator.

  With this configuration, the problem that occurs in the CO detector when the hydrogen-containing gas is burned and discharged by the combustor can be more appropriately addressed than in the past. As described above, the controller shuts off the circuit breaker during a part of the period in which the exhaust gas flows through the first exhaust gas passage. For this reason, since the possibility that the CO detector is exposed to hydrogen gas that promotes the deterioration of the CO detector is reduced as compared with the conventional example in which the CO detector is disposed on the first exhaust gas flow path, the CO detector The possibility of deterioration due to hydrogen exposure is reduced.

[Device configuration]
FIG. 10 is a diagram illustrating an example of the fuel cell system according to the fifth embodiment.

  In the example shown in FIG. 10, the fuel cell system 200 of this embodiment includes a first embodiment, a second embodiment, a first embodiment-fourth embodiment, a third embodiment, and a fourth embodiment of the second embodiment. The hydrogen generator 100 in any form and the fuel cell 20 are provided.

  The fuel cell 20 generates power using the hydrogen-containing gas supplied from the hydrogen generator 100. The fuel cell 20 may be any type of fuel cell. For example, a polymer electrolyte fuel cell (PEFC), a polymer electrolyte fuel cell (SOFC), or a phosphoric acid fuel cell can be used. .

[Operation]
In the power generation operation of the fuel cell system 200, the fuel cell 20 generates power using the hydrogen-containing gas supplied from the hydrogen generator 100.

  At this time, the operation of the hydrogen generation apparatus 100 is the same as that of the fuel cell 20 in the first embodiment, the second embodiment, the first embodiment-fourth embodiment of the second embodiment, the third embodiment, and the fourth embodiment. If considered as a hydrogen-using device that uses a hydrogen-containing gas supplied from any one of the hydrogen generators 100, the first embodiment, the second embodiment, the first example of the second embodiment-the fourth example, The operation is the same as that of any of the third embodiment and the fourth embodiment. Therefore, detailed description is omitted.

  From the foregoing description, many modifications and other embodiments of the present invention are obvious to one skilled in the art. Accordingly, the foregoing description should be construed as illustrative only and is provided for the purpose of teaching those skilled in the art the best mode of carrying out the invention. The details of the structure and / or function may be substantially changed without departing from the spirit of the invention.

  The hydrogen generator according to one embodiment of the present invention can more appropriately cope with the problem that occurs in the CO detector when the hydrogen-containing gas is burned and discharged in the combustor. Thus, one embodiment of the present invention can be used, for example, in a fuel cell system.

DESCRIPTION OF SYMBOLS 1 Reformer 2 Combustor 8 1st exhaust gas flow path 9 CO detector 10 Circuit breaker 11 Branch path 12 Controller 15 External combustion apparatus 16 2nd exhaust gas flow path 20 Fuel cell 100 Hydrogen production | generation apparatus 200 Fuel cell system

Claims (9)

A reformer that generates a hydrogen-containing gas using a raw material, a combustor that burns the hydrogen-containing gas, a first exhaust gas passage through which exhaust gas from the combustor flows, and the first exhaust gas passage In a part of the period in which the exhaust gas flows in the first exhaust gas flow path, the CO detector provided in the branch path, the circuit breaker that interrupts the inflow of exhaust gas to the branch path, And a controller for interrupting the circuit breaker. The hydrogen generation device according to claim 1, wherein when the exhaust gas from the combustor may contain hydrogen, the controller shuts off the circuit breaker. The hydrogen generator according to claim 2, wherein the controller shuts off the circuit breaker when starting the production of a hydrogen-containing gas in the reformer.   The hydrogen generator according to claim 2, wherein the controller shuts off the circuit breaker when the fuel of the combustor is switched from the raw material to the hydrogen-containing gas. The hydrogen generator according to any one of claims 2 to 4, wherein the controller shuts off the circuit breaker during at least a part of a period in which exhaust gas flows through the first exhaust gas passage after extinguishing the combustor. . The first exhaust gas flow path is joined with a second exhaust gas flow path through which exhaust gas from an external combustion device flows, and the controller is configured to start or stop combustion when the external combustion device starts combustion. The hydrogen generator according to claim 2, wherein the circuit breaker is interrupted. The branch path is a bypass flow path that bypasses the first exhaust gas flow path,
At least two of the circuit breakers are provided in the bypass channel;
The hydrogen generator according to claim 1, wherein the CO detector is provided in a bypass flow path between the two circuit breakers.   The hydrogen generator according to claim 1, wherein the controller opens the circuit breaker after the circuit breaker is shut off. A fuel cell system comprising: the hydrogen generator according to claim 1; and a fuel cell that generates electric power using a hydrogen-containing gas supplied from the hydrogen generator.

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