JP2016130196A - Hydrogen generator, operation method of the same and fuel cell system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten the time from starting the stopping process of a hydrogen generator to the completion of purge.SOLUTION: There is provided a hydrogen generator 100 which comprises a reformer 1 for reforming a hydrocarbon-containing raw material to generate a hydrocarbon-containing gas, a raw material gas supplier 2 for supplying the raw material to the reformer 1, a controller 3 which performs normal stop processing or special stop processing different from the normal stop processing and controls to stop the hydrogen generator 100 by supplying the raw material to the reformer 1 as a purge gas, and an input part 4 for inputting from the outside to perform special stop processing, wherein the controller 3 is configured to control so that the stopping time when performing special stop processing is shorter than the stopping time from starting stop processing when performing normal stop processing to the completion of purge of the reformer 1.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a hydrogen generator that reforms a raw material gas containing hydrocarbons to generate hydrogen, and a fuel cell system that includes a fuel cell that generates power using the hydrogen-containing gas obtained by the hydrogen generator. Is.

  A fuel cell capable of high-efficiency power generation even with a small device is a power generator of a distributed energy supply source. Hydrogen gas used as fuel for fuel cell power generation is not developed as a general infrastructure, so when used as a distributed device, for example, it contains hydrocarbons obtained from existing fossil raw infrastructure such as city gas and LPG In many cases, a configuration is employed in which a hydrogen generation apparatus that generates a hydrogen-containing gas by causing a reforming reaction of the raw material gas is also provided.

  For example, in the case of a hydrogen generator that generates a hydrogen-containing gas by a steam reforming reaction, hydrogen is efficiently generated by operating the reformer while maintaining the reformer at a high temperature of about 600 ° C.

  In addition, when the hydrogen generator is stopped, the hydrogen generator, particularly the reformer, is purged with the raw material gas to discharge water vapor in the system and prevent deterioration of the catalyst and the like due to condensed water. Often taken. Then, by completing the purge, the apparatus can be safely stopped without degrading the catalyst or the like even if the power supply or the utility of the source gas is shut off.

  By the way, a hydrogen generator or a fuel cell system may perform regular maintenance or maintenance when an abnormality occurs. The hydrogen generator is kept at a high temperature during operation, but it needs to be cooled so that it can be operated during maintenance. Moreover, it is necessary to cut off utilities such as power supply and gas during maintenance, and it is desirable to quickly shift to a state where the power supply can be cut off.

  In the stop processing when such maintenance work is necessary, the operator can start the maintenance work of the hydrogen generator more quickly by stopping the operation of the hydrogen generator by operating the stop controller. A hydrogen generator that can be used has been proposed (for example, Patent Document 1).

JP 2009-4346 A

  However, as in, for example, Patent Document 1, when only forced cooling is performed by flowing a cooling fluid through the cooling fluid flow path, it takes a long time to complete the purging of the reformer and enter a standby state, thereby improving maintenance. There was still room for improvement.

  Even if the supply of purge gas to the reformer is started and a transition to a standby state is made quickly, carbon is deposited when a purge gas such as hydrocarbon is supplied while the reformer is in a high temperature state. Since it was necessary to start purging after cooling, it took time.

On the other hand, the maintenance that requires work is assumed to have a finite number of times in the lifetime of the hydrogen generator, and maintenance work within the finite number of times is desired to be able to shift to work in a shorter time, and stop. There was room for improvement in characteristics.

  Accordingly, an object of the present invention is to shorten the time from the start of the stop process to the completion of the purge in the hydrogen generator.

  In order to solve the above problems, a hydrogen generator of the present invention includes a reformer that reforms a raw material to generate a fuel gas containing hydrogen, a raw material gas supplier that supplies the raw material to the reformer, A special stop process different from the stop process or the normal stop process is performed, and a controller for controlling the hydrogen generator to stop by supplying the raw material as a purge gas to the reformer and an external input for performing the special stop process are provided. The controller is controlled so that the stop time when the special stop process is performed is shorter than the stop time from the start of the stop process when the normal stop process is performed until the purge of the reformer is completed. To do.

  With this configuration, by performing special stop processing by external input, control is performed to shorten the stop time, that is, the time from the start of the stop processing to the standby state for completion of purge (start-up ready state), thereby maintaining the maintenance. It is possible to improve the performance, that is, to quickly stop the apparatus and proceed to the maintenance work.

  The operation method of the hydrogen generator of the present invention includes a reformer that reforms the raw material to generate a fuel gas containing hydrogen, supplies the raw material as a purge gas to the reformer, and stops the hydrogen generator. The stop time when special stop processing is performed based on the external input is shorter than the stop time from the start of the stop processing when the normal stop step and the normal stop step are performed until the purge of the reformer is completed. And a special stop step of stopping the hydrogen generator by supplying purge gas to the reformer.

  With this configuration, by performing a special stop process based on input from the outside, maintenance is improved by controlling the time from the start of the stop process to the purge completion standby state (start-up ready state). That is, the apparatus can be quickly stopped and the maintenance work can be promptly shifted.

  The hydrogen generation apparatus of the present invention is controlled by a special operation from the outside until the purge is completed until the purge is completed, i.e., the utility is shut off from the stop process and the maintenance work can be started. Maintainability can be improved.

  In addition, by limiting the number of implementations in the lifetime, the hydrogen generating device and the fuel cell system excellent in maintainability can be shortened when the time is required while maintaining the durability.

Schematic of the hydrogen generator in Embodiment 1 of the present invention Explanatory drawing which shows the example of a driving | operation of the raw material purge at the high temperature in this Embodiment Explanatory drawing which shows the example of the raw material purge operation in the shortened time in this Embodiment Explanatory drawing which shows the example of a driving | operation of the purge gas supply amount increase in this Embodiment. Schematic of the fuel cell system in Embodiment 2 of the present invention

A first invention is a hydrogen generator comprising a reformer that reforms a raw material to generate a fuel gas containing hydrogen, and a raw material gas supplier that supplies the raw material to the reformer, A special stop process different from the stop process or the normal stop process is performed, and a controller for controlling the hydrogen generator to stop by supplying the raw material as a purge gas to the reformer and an external input for performing the special stop process are provided. The controller is controlled so that the stop time when the special stop process is performed is shorter than the stop time from the start of the stop process when the normal stop process is performed until the purge of the reformer is completed. A hydrogen generator.

  With this configuration, maintenance is improved by controlling the time from the start of the stop process to the completion of the purge, that is, to cut off the utility from the stop process and start the maintenance work by a special operation from the outside. It can be set as the made hydrogen generation apparatus.

  The second invention is provided with a reforming temperature detector for detecting the temperature of the reformer, particularly in the first invention, and the controller has a temperature of the reformer equal to or lower than the first temperature when performing the normal stop process. Then, the supply of the raw material to the reformer is started as a purge gas, and when the special stop process is performed, the supply of the raw material to the reformer as the purge gas starts when the temperature of the reformer falls below a second temperature higher than the first temperature. It is a hydrogen generator to be controlled.

  With this configuration, when performing the special stop process, the purge is completed earlier by starting the purge from a higher temperature state (second temperature) without waiting for the temperature to decrease to the predetermined temperature (first temperature). The stop time can be shortened and a hydrogen generator excellent in maintainability can be obtained.

  According to a third aspect of the invention, particularly in the first or second aspect of the invention, the controller has a purge time for performing the special stop process rather than a purge time for supplying the purge gas to the reformer when performing the normal stop process. This is a hydrogen generator that is controlled to be shortened.

  With such a configuration, when performing the special stop process, the purge time can be shortened, the purge can be completed earlier and the stop time can be shortened, and a hydrogen generator excellent in maintainability can be obtained.

  In the fourth invention, particularly in the first to third inventions, the controller has a larger purge gas supply amount when performing the special stop process than a purge gas supply amount of the reformer when performing the normal stop process. The hydrogen generator is controlled as follows.

  With this configuration, when performing a special stop process, it is possible to cool faster by increasing the supply amount of the purge gas, and to achieve a predetermined amount of the total purge gas amount even in a short time, and maintainability while maintaining the purge performance. Can be improved.

  According to a fifth aspect of the invention, in particular, in the first to fourth aspects of the invention, the controller includes a storage unit that stores the number of special stop processes, and the controller does not perform the special stop process when the number of special stop processes exceeds a predetermined number. , A hydrogen generator.

  With this configuration, if all stop processes are specially stopped in the lifetime, maintenance can be performed while maintaining durability by maintaining a limited number of special stop processes even when there are durability issues. It can be set as the hydrogen generator which improved the property.

  A sixth invention is a fuel cell system comprising, in particular, the hydrogen generator of any one of the first to fifth inventions, and a fuel cell that generates electric power using fuel gas supplied from the hydrogen generator.

With this configuration, maintenance is improved by controlling the time from the start of the stop process to the completion of the purge, that is, to cut off the utility from the stop process and start the maintenance work by a special operation from the outside. It can be set as the made fuel cell system.

  A seventh invention is an operation method of a hydrogen generator having a reformer that reforms a raw material to produce a fuel gas containing hydrogen, and supplies the raw material as a purge gas to the reformer to generate the hydrogen generator The stop time when performing special stop processing based on input from the outside is shorter than the stop time from the start of stop processing when performing the normal stop step to the completion of the reformer purge. Thus, there is provided a special stopping step of supplying a purge gas to the reformer to stop the hydrogen generator, and a method for operating the hydrogen generator.

  With such a configuration, by performing a special stop process based on an external input, control is performed to shorten the time from the start of the stop process until the purge is completed, that is, the time from the stop process to the time when the utility can be shut off and the maintenance work can be started. Thus, the operation method of the hydrogen generator with improved maintainability can be obtained.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(Embodiment 1)
FIG. 1 shows a schematic diagram of a hydrogen generator according to Embodiment 1 of the present invention.

  The hydrogen generator in Embodiment 1 includes a reformer 1 that reforms a raw material gas containing hydrocarbons to generate a hydrogen-containing gas, a raw material gas supply device 2 that supplies the raw material to the reformer 1, A normal stop process or a special stop process different from the normal stop process is performed, and the controller 3 for controlling the hydrogen generator 100 to stop by supplying the raw material as the purge gas to the reformer 1 and the special stop process are performed. And an input unit 4 input from the outside.

  Here, the input unit 4 is configured to input using a remote controller. For example, it may be configured to input remotely through an Internet line, and the input means from the outside is not limited to this.

  As a method for generating hydrogen, here, a steam reforming reaction for reforming hydrocarbons and steam is used, and a Ru-based catalyst is used as a reforming catalyst charged in the reformer 1. When the steam reforming reaction is used, water may be supplied to the reformer 1 by the water supplier 5. Moreover, although the steam reforming reaction is mentioned here as the reforming reaction, the same effect can be obtained by, for example, autothermal reaction or partial oxidation reforming.

  The reformer 1 may be structured to be heated by heat transfer from the combustor 6, and the outside of the reformer 1 may be covered with a heat insulating material (not shown). In the combustor 6, the raw material gas or the hydrogen-containing gas may be burned. The combustion air may be supplied to the combustor 6 by the combustion air supply device 7.

  In addition, a reforming temperature detector 10 for measuring the temperature of the reformer 1 is provided. Here, a thermocouple is provided on the outlet side of the reformer 1.

  Moreover, it is good also as a structure provided with the memory | storage part 11 which memorize | stores the frequency | count of a special stop process, and it was comprised so that the frequency | count may be memorize | stored in memory, when inputting to perform the special stop process from the outside by the input part 4.

Next, the operation of the hydrogen generator in Embodiment 1 of the present invention will be described. The following operations are performed by the controller 3 controlling each device of the hydrogen generator 100.

  The controller 3 controls the raw material gas supply device 2 to supply the raw material gas to the reformer 1. Here, a booster pump for boosting the source gas was used as the source gas supply unit 2 to supply the source gas. The raw material gas may be supplied by desulfurizing sulfur components in the raw material gas through a desulfurizer (not shown).

  The flow rate of the raw material gas is preferably set in consideration of the composition of the raw material gas based on the flow rate of the hydrogen-containing gas or hydrogen gas to be generated, and is set here to 3.0 NL / min.

  Further, the controller 3 controls the water supply device 5 to supply water vapor (hereinafter referred to as reformed water) necessary for the steam reforming reaction to the reformer 1. In the present embodiment, the flow rate of the reforming water is supplied so that S / C indicating the ratio of water to the number of carbons in the raw material gas supplied to the reformer 1 is 2.9.

  The raw material gas and the reformed water supplied to the reformer 1 are maintained at about 600 ° C. in the presence of the reforming catalyst inside the reformer 1 and reformed into a hydrogen-containing gas by a steam reforming reaction.

  The controller 3 also controls the combustion air supply unit 7 to supply combustion air necessary for burning the raw material gas or the hydrogen-containing gas supplied to the combustor 6. Here, the flow rate of the combustion air was controlled to be 1.7 as an air ratio representing the supply air flow rate with respect to the theoretical combustion air flow rate.

[Normal stop processing method]
Next, a normal stop processing method for the hydrogen generator in Embodiment 1 of the present invention will be described.

  Here, the normal stop process is a stop process that is executed when, for example, hydrogen generated by the hydrogen generator 100 does not need to be used in the hydrogen using device 110. Specifically, for example, when the hydrogen using device is a fuel cell, the power demand of the power load and the heat demand of the heat load are executed at a predetermined value or less, or a preset planned stop time is reached. Examples include stop processing to be executed.

  In the present invention, the stop process (stop operation) is defined as the operation from when the controller 3 outputs a stop signal until the hydrogen generator 100 completes the stop process. In addition, after the normal stop process of the hydrogen generator 100 is completed, the apparatus enters a standby state.

  During the normal stop process of the hydrogen generator 100, first, when a stop command is output from the controller 3, the operation of the raw material gas supplier 2 and the water supplier 5 is stopped and provided at the entrance / exit in the hydrogen generator path. The hydrogen generation apparatus 100 is sealed by closing a valve (not shown). When the supply of the combustible gas to the combustor 6 is stopped, the combustion in the combustor 6 is stopped.

  The combustion air supply unit 7 was controlled so as to continue supplying the combustion air even after the combustion in the combustor 6 was stopped. Thereby, the hydrogen generator, particularly the reformer 1 and the combustor 6 are cooled to a predetermined temperature.

  During the cooling operation, the temperature T of the reformer 1 detected by the reforming temperature detector 10 provided in the reformer 1 of the hydrogen generator 100 is equal to or lower than a standby temperature (for example, 500 ° C.). In some cases, the combustion air supplier 7 stops the supply of combustion air to the combustor 6 and completes the cooling operation of the hydrogen generator 100.

The predetermined temperature is a temperature at which the hydrogen generator 100 can shift to a standby state, and is defined as an upper limit temperature at which carbon deposition does not occur even when only the source gas is supplied to the hydrogen generator 100, for example. Good.

  When the cooling operation of the hydrogen generator 100 is completed, the hydrogen generator 100 shifts to a standby state. Note that this standby state is a state in which the next hydrogen generator 100 is awaiting the start of operation, and a start command is output from the controller 3 so that the next start process is executed. Defined as state.

  Examples of the activation request include, for example, that the user operates the remote controller to make an operation start request, or that the hydrogen using device 110 needs to use hydrogen. For this reason, when the startup process is output from the controller 3 while the hydrogen generator 100 is in a standby state, the startup process of the hydrogen generator 100 is performed.

  In the standby state, the hydrogen generator 100 is allowed to cool naturally. At this time, the temperature T of the reformer 1 detected by the reforming temperature detector 10 is a first temperature (lower than the standby temperature) ( When the temperature is 300 ° C. or lower, the closed valve is opened, and the raw material gas (purge gas) is supplied from the raw material gas supply device 2 to the hydrogen generator 100.

  A gas such as water vapor existing in a reactor (for example, the reformer 1) provided in the hydrogen generator 100 is purged by the raw material gas, scavenged from the hydrogen generator 100 (hereinafter referred to as a purge process), and combusted. It is burned in the vessel 6.

  Here, the purge flow rate of the source gas was set to 1.0 NLM. By this purge process, it is possible to suppress deterioration of the catalyst such as the reforming catalyst due to dew condensation of water vapor in the hydrogen generator 100.

  The purge temperature is modified by a combustion operation in the combustor 6 during the purge process for the hydrogen generator 100 in consideration of the correlation between the temperature detected by the reforming temperature detector 10 and the actual catalyst temperature. Even if the temperature rise of the mass device 1 is added, it should be defined as a sufficiently low temperature at which the raw material gas does not carbon deposit on the catalyst in the reformer 1.

  Then, the controller 3 measures the elapsed time t from the start of the purge process, and when the purge time t0 (here 10 minutes) or more is reached, stops the source gas supply device 2 and closes the valve. The normal stop process is terminated. The purge time t0 is preferably defined as the time necessary for at least the water vapor in the hydrogen generator 100 to be sufficiently scavenged at the purge flow rate (here, 1.0 NLM).

  As described above, in the hydrogen generator 100 according to the first embodiment, when the operation is stopped in a normal state, at least the stop process that protects the function of the hydrogen generator 100 is executed and promptly performed. It is configured to enter a standby state.

  Further, even when the cooling operation is performed, the minimum necessary cooling operation such as the exhaust heat recovery operation is performed only until the temperature of the hydrogen generating apparatus 100 reaches a restartable temperature state. ing.

  Therefore, it is possible to quickly shift to the standby state, and in the next start-up process, depending on the elapsed time since the shift to the standby state, the equipment temperature (for example, the reformer 1) constituting the hydrogen generator 100 is changed to the ambient temperature ( The temperature required to raise the temperature of the hydrogen generator 100 is reduced, the time required for the startup process is shortened, and the startability of the hydrogen generator 100 is improved.

[Special stop processing method]
Next, the special stop processing method of the hydrogen generator in Embodiment 1 of this invention is demonstrated.

  When the controller 3 is input from the outside to perform the special stop process through the input unit 4, the special stop process is longer than the stop time from the start of the stop process when the normal stop process is performed until the purge of the reformer 1 is completed. Control is performed so as to shorten the stop time when the operation is performed. Here, the input unit 4 is configured to input using a remote controller.

  For example, it may be configured to input remotely through an Internet line, and the input means from the outside is not limited to this. In the stop process of the normal stop process, even when the input unit 4 inputs from the outside to perform the special stop process, the stop process may be performed as the special stop process from that timing.

  As described above, control is performed so as to shorten the stop time when the special stop process is performed. More specifically, the controller 3 sets the temperature of the reformer 1 to the first temperature (when the normal stop process is performed). In this case, the supply of the raw material to the reformer 1 as a purge gas is started at a temperature lower than 300 ° C.), and when the special stop process is performed, the temperature of the reformer 1 is higher than the first temperature (here 300 ° C.). In this case, it may be controlled to start supplying the raw material as a purge gas to the reformer when the temperature is 400 ° C. or lower.

  FIG. 2 is an explanatory diagram showing an example of a raw material purge operation at a high temperature in the present embodiment. Here, t1 indicates a purge time when the special stop process is performed, and t0 indicates a purge time when the normal stop process is performed. If the purge amount is the same, the purge can be completed earlier and the stop time can be shortened by starting the purge at a higher temperature.

  Here, considering the correlation between the temperature detected by the reforming temperature detector 10 and the actual catalyst temperature, the second temperature starts the purge process and the temperature of the reformer 1 due to the combustion operation in the combustor 6. Even if the amount of increase is added, the temperature is preferably defined as a temperature at which carbon deposition due to the raw material gas in the reformer 1 does not have a great influence, and is 400 ° C. here.

  In the normal stop process, the purge process is started after the temperature of the reformer 1 becomes sufficiently low. However, in the special stop process, maintenance is emphasized, and a range in which carbon deposition is not problematic is assumed. To implement. With such a configuration, the utility can be shut off early and the maintainability can be improved by completing the purge early and shortening the stop time during the special stop process during the maintenance.

  In addition, the controller 3 performs the purge time t1 (here, 5 minutes) when performing the special stop process, rather than the purge time t0 (here, 10 minutes) in which the purge gas is supplied to the reformer 1 when performing the normal stop process. ) May be controlled to be shorter.

  FIG. 3 is an explanatory diagram showing an example of a raw material purge operation with a shortened time in the present embodiment. By shortening the purge time, for example, if the purge process start temperature is the same, the purge can be completed earlier and the stop time can be shortened.

  In the purge process at the par time t1 (here, 5 minutes) by the special stop process, it may be defined as the time during which the water vapor in the hydrogen generator 100 is scavenged to a remaining amount in a range where there is no problem.

  In the normal stop process, the time required for at least the water vapor in the hydrogen generating apparatus 100 to be sufficiently scavenged is assumed, but here, maintenance is emphasized and the range where condensation due to the remaining amount of water vapor is not problematic is assumed. carry out.

  With this configuration, it is possible to shorten the time until the utility can be cut off and improve the maintainability. It may be controlled such that the start temperature of the purge process is higher than the first temperature and the purge time is shortened. Further, the controller 3 may perform control so that the purge gas supply amount when performing the special stop process is larger than the purge gas supply amount of the reformer 1 when performing the normal stop process.

  FIG. 4 is an explanatory diagram showing an operation example of increasing the purge gas supply amount in the present embodiment. Here, the purge in the normal stop process is supplied at 1.0 NL / min for 10 minutes, and the purge in the special stop process is supplied at 1.5 NL / min for 7 minutes.

  By increasing the supply amount of the purge gas, it is possible to cool more quickly and to achieve a predetermined total purge gas amount even in a short time, and maintainability can be improved while maintaining the purge performance. In addition, you may combine with any one or more of the control which makes the start temperature of purge processing higher than 1st temperature, or shortens purge time.

  Further, the temperature of the reformer 1 rises with combustion in the combustor 6 by the purge process, but the temperature rise is delayed due to the heat capacity of the reformer 1 and the like compared to the start of the purge process. Therefore, even if the purge processing start temperature is set higher than the first temperature, for example, by shortening the purge time, the purge can be terminated before the reformer rises to a temperature that affects carbon deposition.

  In addition, the storage unit 11 that stores the number of special stop processes stores the number of times that the input unit 4 is used to perform the special stop process from the outside, and the controller 3 determines that the number of special stop processes is a predetermined number of times. Control may be performed so that the special stop process is not performed when the value exceeds.

  Here, the normal stop process needs to be a stop method that does not have a problem in durability even if the number of stoppages of accumulation in the lifetime (here, 5000 times) is repeated. On the other hand, the special stop treatment can be severer conditions such as carbon deposition and water vapor condensation than the normal stop, and there is a concern that the durability is lowered when the same number of times as the normal stop (here, 5000 times) is repeated. There is.

  Therefore, the stop method is limited only to the time when maintenance work is required, and here, the control is performed so that the special stop process is not performed when the number of special stop processes exceeds a predetermined number (here, 50 times).

  In general, regular maintenance work that requires equipment maintenance and maintenance in the event of equipment failure is assumed to be within 50 times in the life cycle (for example, 10 years). While maintaining the above, a hydrogen generator excellent in maintainability can be obtained.

(Modification 1)
Next, a first modification of the hydrogen generator in Embodiment 1 of the present invention will be described.

  The characteristic operation in the present modification will be described, but the difference from the first embodiment will be described, and the rest will be the same as in the first embodiment.

[Normal stop processing method]
Since the normal stop processing method of the hydrogen generator in the first modification can be the same as that in the first embodiment, detailed description thereof is omitted.

[Special stop processing method]
Next, a special stop processing method for the hydrogen generator in Modification 1 will be described.

  The controller 3 is shorter than the stop time from the start of the stop process when the normal stop process is performed until the purge of the reformer 1 is completed, and the stop time when the special stop process is input from the input unit 4 from the outside becomes shorter. Control as follows.

  In the first modification, the combustion air supplier 7 continues to supply the combustion air to the combustor 6 even after the combustion in the combustor 6 is stopped by the control of the controller 3, and the hydrogen generator 100. The cooling operation was controlled to continue. Then, when the temperature detected by the reforming temperature detector 10 becomes equal to or lower than the first temperature (here, 300 ° C.) while the cooling operation of the hydrogen generator 100 is continued, a purge process is executed.

  When the purge process is completed, the combustion air supplier 7 is stopped and the cooling operation is completed. The purging process here is performed when the temperature of the reformer 1 becomes equal to or lower than the second temperature (here, 400 ° C.) higher than the first temperature (here, 300 ° C.) so as to shorten the time until the purge is completed. 1 may be controlled to start supplying the raw material as a purge gas.

  In addition, the controller 3 performs the purge time t1 (here, 5 minutes) when performing the special stop process, rather than the purge time t0 (here, 10 minutes) in which the purge gas is supplied to the reformer 1 when performing the normal stop process. ) May be controlled to be shorter.

  Further, the controller 3 may perform control so that the purge gas supply amount when performing the special stop process is larger than the purge gas supply amount of the reformer 1 when performing the normal stop process.

  In addition, the storage unit 11 that stores the number of special stop processes stores the number of times that the input unit 4 is used to perform the special stop process from the outside, and the controller 3 determines that the number of special stop processes is a predetermined number of times. Control may be performed so that the special stop process is not performed when the value exceeds.

  With this configuration, it is possible to continue cooling the hydrogen generator 100, particularly the reformer 1, with the combustion air supply 7 by a special operation from the outside, and to shorten the time until the purge is completed. Cooling and purging are completed, and a hydrogen generator excellent in maintainability can be obtained.

(Modification 2)
Next, Modification 2 of the hydrogen generator in Embodiment 1 of the present invention will be described.

  The characteristic operation in the present modification will be described, but the difference from the first embodiment will be described, and the rest will be the same as in the first embodiment.

[Normal stop processing method]
Next, a normal stop processing method for the hydrogen generator in Modification 2 will be described.

  During the normal stop process of the hydrogen generator 100, first, when a stop command is output from the controller 3, the operation of the raw material gas supplier 2 and the water supplier 5 is stopped and provided at the entrance / exit in the hydrogen generator path. The hydrogen generation apparatus 100 is sealed by closing a valve (not shown). When the supply of the combustible gas to the combustor 6 is stopped, the combustion in the combustor 6 is stopped.

  The combustion air supplier 7 continues the supply of the combustion air to the combustor 6 even after the combustion in the combustor 6 is stopped under the control of the controller 3, and executes the cooling operation of the hydrogen generator 100. The cooling operation continues even when the temperature detected by the reforming temperature detector 10 provided in the reformer 1 of the hydrogen generator 100 is equal to or lower than the standby temperature (for example, 500 ° C.).

  Then, when the temperature detected by the reforming temperature detector 10 becomes equal to or lower than the first temperature (here, 300 ° C.) while the cooling operation of the hydrogen generator 100 is continued, a purge process is executed. When the purge process is completed, the combustion air supplier 7 is stopped and the cooling operation is completed.

  In other words, in the present modification, the normal stop process is performed when control is continued from the start of the stop process until the purge process is performed. The normal stop process of this modification is performed, for example, when it is better to once cool the hydrogen generator at the time of stop by a device (for example, a gas sensor) constituting the hydrogen generator.

[Special stop processing method]
Since the special stop processing method of the hydrogen generator in the second modification can be the same as that in the first embodiment, detailed description thereof is omitted.

  The controller 3 is shorter than the stop time from the start of the stop process when the normal stop process is performed until the purge of the reformer 1 is completed, and the stop time when the special stop process is input from the input unit 4 from the outside becomes shorter. Control as follows.

  With this configuration, maintenance is improved by controlling the time from the start of the stop process to the completion of the purge, that is, to cut off the utility from the stop process and start the maintenance work by a special operation from the outside. It can be set as the made hydrogen generation apparatus.

  As described above, the first embodiment and the second modification are different in whether or not the combustion air supplier 7 is continuously operated and the hydrogen generator 100 is continuously cooled during the normal stop process. That is, regardless of the method of the normal stop process, the special stop process is controlled so that the time until the purge is completed is shorter, so that the hydrogen generator having better maintainability can be obtained.

(Embodiment 2)
Next, a fuel cell system according to Embodiment 2 of the present invention will be described. FIG. 5 shows a schematic diagram of a fuel cell system according to Embodiment 2 of the present invention. The same or corresponding parts as those in the embodiment shown in FIG.

  In the present embodiment, the fuel cell 20 that generates power using the hydrogen-containing gas supplied from the hydrogen generator 100 is provided.

  As the fuel cell 20, a polymer electrolyte fuel cell (PEFC) is used here. Since the voltage of a fuel cell is generally lowered by carbon monoxide, it is necessary to reduce the carbon monoxide to approximately 10 ppm or less at the CO removal unit.

  Here, the hydrogen-containing gas containing carbon monoxide obtained in the reformer 1 is supplied to the CO remover 31 after the carbon monoxide is reduced stepwise through the converter 30. In this case, the transformer 30 is configured to use a Cu—Zn-based catalyst at 200 to 300 ° C., and the CO removal unit is configured to use a Ru-based selective oxidation catalyst at about 150 ° C. for reaction to remove CO.

  Next, an operation method of the fuel cell system will be described.

  The controller 3 supplies the hydrogen-containing gas as the fuel gas of the fuel cell 20 to the anode of the fuel cell 20. In the fuel cell 20, the fuel gas supplied to the anode and the power generation air supplied to the cathode react electrochemically to generate electricity, heat, and water.

  The electricity obtained by the fuel cell 20 is supplied to a power load (not shown) and used. On the other hand, the heat generated by the power generation is recovered by a heat recovery means (not shown) and supplied to the heat load for various uses. Used in Unreacted fuel gas that has not been consumed inside the fuel cell 20 is supplied to the combustor 6.

  The controller 3 controls the combustion air supply unit 7 and supplies combustion air necessary for burning off gas supplied to the combustor 6. In the combustor 6, the off-gas and the combustion air supplied from the combustion air supply unit 7 are mixed and burned to supply heat necessary for the steam reforming reaction in the reformer 1. Here, the flow rate of the combustion air was controlled to be 1.7 as an air ratio representing the supply air flow rate with respect to the theoretical air flow rate.

  Further, the controller 3 calculates a hydrogen production amount to be generated from a raw material flow rate detected by the raw material flow rate detector 8 and a hydrocarbon conversion rate calculated from a temperature detected by the reforming temperature detector 10. The power generation amount in the fuel cell 20 is instructed so that power can be generated within a predetermined hydrogen utilization rate range.

  Here, 750 W was instructed as the power generation instruction amount so that the hydrogen utilization rate was about 80%, and power was generated. Here, the hydrogen utilization rate may be set to be between 70 and 85% for stable operation.

  Next, characteristic operations in the present embodiment will be described. Differences from the first embodiment will be described, and the rest will be the same as in the first embodiment.

  The controller 3 performs control so that the stop time for performing the special stop process is shorter than the stop time from the start of the stop process for performing the normal stop process to the completion of the purge of the reformer 1.

  In addition, when the normal stop process is performed, the controller 3 starts supplying the raw material as a purge gas to the reformer 1 when the temperature of the reformer 1 becomes equal to or lower than the first temperature (300 ° C. here), and performs a special stop process. When performing, when the temperature of the reformer falls below a second temperature (here, 400 ° C.) higher than the first temperature (here, 300 ° C.), it may be controlled to start supplying the raw material to the reformer as a purge gas.

  In addition, the controller 3 performs the purge time t1 (here, 5 minutes) when performing the special stop process, rather than the purge time t0 (here, 10 minutes) in which the purge gas is supplied to the reformer 1 when performing the normal stop process. ) May be controlled to be shorter.

  Further, the controller 3 may perform control so that the purge gas supply amount when performing the special stop process is larger than the purge gas supply amount of the reformer 1 when performing the normal stop process.

  In addition, the storage unit 11 that stores the number of special stop processes stores the number of times that the input unit 4 is used to perform the special stop process from the outside, and the controller 3 determines that the number of special stop processes is a predetermined number of times. Control may be performed so that the special stop process is not performed when the value exceeds.

  With this configuration, maintenance can be performed by reducing the stop time from the start of the stop process to the completion of the purge, that is, the time from the stop process to starting the maintenance work by shutting down the utility by a special operation from the outside. The fuel cell system can be improved.

  The present invention provides a hydrogen generator and a fuel cell system capable of shortening the time from the stop process to shutting down the utility and starting the maintenance work, and improving the maintainability. It is useful as a distributed hydrogen generator and a fuel cell system that are required to be stopped and ready to work.

DESCRIPTION OF SYMBOLS 1 Reformer 2 Raw material gas supply device 3 Controller 4 Input part 5 Water supply device 6 Combustor 7 Combustion air supply device 8 Raw material flow rate detector 10 Reforming temperature detector 11 Memory | storage part 20 Fuel cell 30 Transformer 31 CO Remover 100 Hydrogen generator 110 Hydrogen utilization equipment

Claims (7)

A reformer that reforms the raw material to produce fuel gas containing hydrogen;
A raw material gas supply device for supplying a raw material to the reformer;
A hydrogen generator comprising:
A controller that performs a normal stop process or a special stop process different from the normal stop process, and controls the hydrogen generator to stop by supplying the raw material as a purge gas to the reformer;
An input unit input from the outside to perform the special stop process;
With
The controller controls the stop time when performing the special stop process to be shorter than the stop time from the start of the stop process when performing the normal stop process to the completion of purging of the reformer,
Hydrogen generator. A reforming temperature detector for detecting the temperature of the reformer,
The controller starts supplying the raw material as a purge gas to the reformer when the temperature of the reformer becomes equal to or lower than the first temperature when the normal stop process is performed, and the reformer when the special stop process is performed. 2. The hydrogen generation apparatus according to claim 1, wherein when the temperature of the mass device becomes equal to or lower than a second temperature higher than the first temperature, the reformer is controlled to start supplying the raw material as a purge gas.   The controller controls the purge time for performing the special stop process to be shorter than the purge time for supplying purge gas to the reformer when the normal stop process is performed. The hydrogen generator described in 1.   4. The controller according to claim 1, wherein the controller controls the purge gas supply amount when the special stop process is performed to be larger than a purge gas supply amount of the reformer when the normal stop process is performed. The hydrogen generator according to any one of the above. A storage unit for storing the number of times of the special stop process;
The hydrogen generator according to any one of claims 1 to 4, wherein the controller does not perform the special stop process when the number of the special stop processes exceeds a predetermined number.   A fuel cell system comprising: the hydrogen generator according to any one of claims 1 to 5; and a fuel cell that generates electric power using fuel gas supplied from the hydrogen generator. A method for operating a hydrogen generator comprising a reformer that reforms a raw material to produce a fuel gas containing hydrogen,
A normal stopping step of stopping the hydrogen generator by supplying a raw material as a purge gas to the reformer;
Based on the input from the outside, the stop time when the special stop process is performed is shorter than the stop time from the start of the stop process when the normal stop process is performed to the completion of purge of the reformer. A special stop step of stopping the hydrogen generator by supplying a purge gas to the reformer;
A method for operating the hydrogen generator.