JP2020200211A - Hydrogen production apparatus and its operation method - Google Patents

Abstract

To provide a hydrogen production apparatus with which a starting time when restarting a hydrogen production operation of the hydrogen production apparatus is shortened.SOLUTION: A controller 80 stops the operation of a raw material feeder 13, a water feeder 14, a power source 30, and a heater 12 when the hydrogen production operation of a hydrogen production apparatus 100 is stopped, closes a purified hydrogen gas passage opening/closing valve 54 and an off-gas passage opening/closing valve 52, and when the hydrogen production operation is resumed, opens a reflux passage opening/closing valve 53 to allow a purified hydrogen gas passage 45 and a raw material supply passage 40 to communicate with each other via a reflux passage 44 before the raw material feeder 13 is operated for operating the power source 30 and the heater 12, so that hydrogen gas of a hydrogen-containing gas and purified hydrogen gas remaining inside the hydrogen production apparatus 100 circulates through the annular passage and heats a CO reducer 16. At this time, since it is not necessary to intermittently operate the heater 12 so as not to reach a temperature at which carbon deposition occurs in a reformer 11, the starting time can be shortened.SELECTED DRAWING: Figure 1

Description

The present invention uses a reformer and a CO reducer to generate a hydrogen-containing gas from a hydrocarbon-based raw material, and an electrochemical device that generates purified hydrogen gas having high hydrogen purity from the hydrogen-containing gas. The present invention relates to a hydrogen production apparatus including the above, and an operation method thereof.

The hydrogen production device is a device that produces (separates) purified hydrogen gas having a higher hydrogen purity than the hydrogen-containing gas by utilizing an electrochemical reaction from the hydrogen-containing gas. In this hydrogen production apparatus, for example, an electrolyte membrane-electrode assembly (MEA) having a structure in which an electrolyte membrane that selectively transports (permeates) hydrogen ions is sandwiched between an anode and a cathode is sandwiched between a pair of separators. Equipped with a device.

Then, the hydrogen-containing gas is supplied to the anode, the potential of the anode is made higher than the potential of the cathode, and a current is passed from the anode to the cathode through the electrolyte membrane. An oxidation reaction in which hydrogen dissociates into hydrogen ions and electrons occurs, and a reduction reaction in which hydrogen ions and electrons combine to form hydrogen, as shown in (Chemical Formula 2), occurs at the cathode.

以上の反応により、アノードに供給された水素を含む混合ガスから、水素をカソードに分離することができる。

By the above reaction, hydrogen can be separated into the cathode from the mixed gas containing hydrogen supplied to the anode.

The hydrogen-containing gas supplied to this electrochemical device reforms hydrocarbon-based raw materials (for example, 13A gas, liquefied petroleum gas, etc.) by a hydrogen generator having a fuel processor (reformer) (steam reforming). It is produced by quality or partial oxidation reforming (see, for example, Patent Document 1). The hydrogen-containing gas produced in this way contains impurities such as carbon dioxide, methane, nitrogen, carbon monoxide, and water vapor.

Since the hydrogen-containing gas generated from the reformer contains carbon monoxide (CO) generated at the same time as hydrogen, equipment using a material poisoned by carbon monoxide such as a solid polymer fuel cell. When the hydrogen-containing gas is supplied to the hydrogen-containing gas, a CO-reducing device is provided after the reformer, and the CO concentration of the hydrogen-containing gas is reduced by the CO-reducing device.

In order to bring the reformer and the CO reducer to a temperature suitable for each reaction, the reformer and the CO reducer are heated by a heater. As a heater, both the reformer and the CO reducer are heated by off-gas including combustible gas discharged from the reformer and not used in the fuel cell, and heat generated when burning hydrocarbon fuel. A combustor (burner) is generally used.

Generally, the temperature of the reformer is about 700 ° C. and the temperature of the CO reducer is about 300 ° C. In this way, in order to keep the temperature of the reformer and CO reducer at the optimum temperature for the reaction of each catalyst, the heater is installed near the reformer where the temperature needs to be the highest, and at startup. A heater is also used to raise the temperature of the reformer and CO reducer.

Further, since the CO reducer takes longer to raise the temperature by the heater than the reformer, it has been proposed to provide the CO reducer with a dedicated starter heater (see, for example, Patent Document 2).

Special Table 2016-530188 Japanese Unexamined Patent Publication No. 2008-156154

However, in the hydrogen generator disclosed in Patent Document 2, the start-up time of the hydrogen generator is increased by providing a dedicated start-up heater in the CO-reducer, which takes longer to raise the temperature by the heater than the reformer. However, there is a problem that the configuration of the hydrogen generator becomes complicated, the cost of the hydrogen generator becomes high, and energy for operating the starter heater is required.

Therefore, instead of providing a dedicated starter heater in the CO reducer, the amount of heating is higher than in the hydrogen generation operation by using a heater for both the reformer and the CO reducer while flowing the raw material to the reformer at the time of start-up. When the temperature is increased by heating and raising the temperature, the temperature of the reformer reaches the temperature at which carbon precipitation occurs before the temperature of the CO reducer reaches the dew point in the CO reducer when the raw material and steam are circulated. It ends up.

Therefore, when the temperature of the reformer reaches the temperature at which carbon precipitation occurs, the heater is stopped until a predetermined condition is satisfied so that the temperature of the reformer does not exceed the temperature at which carbon precipitation occurs, and the heater is stopped while the heater is stopped. The dew point in the CO reducer when the heater is operated intermittently and the temperature of the CO reducer is changed between the raw material and steam so that the heating operation of the heater is restarted when the predetermined conditions are satisfied. The temperature will rise to.

However, in order to suppress the overheating of the reformer, when the heating operation of the heater is stopped, the temperature rise of the CO reducer is also suppressed, so that both the reformer and the CO reducer are reacted. Even if the heating amount of the heater is increased for the purpose of shortening the time for raising the temperature to a suitable temperature, the number of times the heating operation of the heater and its stop are repeated only increases, and the time required for starting cannot be sufficiently shortened. Had the problem.

The present invention solves the above-mentioned conventional problems, and provides a hydrogen production apparatus and an operation method thereof capable of shortening the activation time of the hydrogen production apparatus without providing a dedicated activation heater in the CO reducer. The purpose is.

In order to solve the above-mentioned conventional problems, the hydrogen production apparatus of the present invention has an electrolyte membrane between the anode and the cathode, supplies hydrogen-containing gas to the anode, and has a predetermined direction between the anode and the cathode. An electrochemical device that generates purified hydrogen gas at the cathode, a power source that allows current to flow between the anode and the cathode, and a modification that reforms hydrocarbon-based raw materials to generate hydrogen-containing gas. A pawnbroker, a CO reducer that reduces the concentration of carbon monoxide contained in the hydrogen-containing gas generated by the reformer and supplied to the anode, and a raw material that supplies the raw material to the reformer via the raw material supply flow path. A feeder, a heater that heats a reformer and a CO reducer, a purified hydrogen gas flow path for supplying purified hydrogen gas to a hydrogen utilization device, and a refined hydrogen gas flow that can open and close the purified hydrogen gas flow path. A refined hydrogen gas flow path on-off valve provided in the path, and a return flow path that branches from the flow path on the upstream side of the refined hydrogen gas flow path on-off valve in the refined hydrogen gas flow path and joins the raw material supply flow path. A hydrogen production device provided with a recirculation flow path on-off valve and a controller, which are provided in the recirculation flow path so as to be able to open and close the recirculation flow path. The controller is a raw material supply device, a power source, and a heater, respectively. When the hydrogen production device is operating to produce hydrogen by operating, the hydrogen production operation of the hydrogen production device is maintained by maintaining the closed state of the recirculation flow path on-off valve and the open state of the purified hydrogen gas flow path on-off valve. When the operation of the raw material supply device, the power supply, and the heater is stopped, the refined hydrogen gas flow path on-off valve is closed, and when the hydrogen production operation is restarted, the raw material supply device is operated. Previously, the power supply and the heater are operated with the purified hydrogen gas flow path on-off valve closed and the recirculation flow path on-off valve open.

The hydrogen production device having the above configuration uses the hydrogen gas of the hydrogen-containing gas and the purified hydrogen gas remaining inside the hydrogen production device as a recirculation flow path and an electrochemical function as a hydrogen pump when the hydrogen production operation is restarted. The reformer and the CO reducer are heated by the heater while circulating by the device.

Therefore, since hydrogen gas is used as the heating gas of the reformer and the CO reducer, the temperature of the reformer is set to the temperature at which carbon precipitation occurs in the reformer when the temperature of the reformer and the CO reducer is raised. Since it is not necessary to operate the heater so as not to cause the problem, the start-up time when the heater is continuously operated and the hydrogen production operation is restarted can be shortened as compared with the conventional case. Therefore, it is possible to provide a hydrogen production apparatus having an improved operating rate.

According to the present invention, when the hydrogen production operation is restarted, the hydrogen gas of the hydrogen-containing gas and the purified hydrogen gas remaining inside the hydrogen production apparatus is separated by a recirculation flow path and an electrochemical device functioning as a hydrogen pump. The reformer and the CO reducer are heated by the heater while circulating.

Therefore, since hydrogen gas is used as the heating gas of the reformer and the CO reducer, the temperature of the reformer is set to the temperature at which carbon precipitation occurs in the reformer when the temperature of the reformer and the CO reducer is raised. Since it is not necessary to operate the heater so as not to cause the problem, the start-up time when the heater is continuously operated and the hydrogen production operation is restarted can be shortened as compared with the conventional case. Therefore, it is possible to provide a hydrogen production apparatus having an improved operating rate.

The block diagram which shows the structure of the hydrogen production apparatus in Embodiment 1 of this invention. A flowchart showing an operation when restarting the hydrogen production operation of the hydrogen production apparatus according to the first embodiment of the present invention. The block diagram which shows the structure of the hydrogen production apparatus in Embodiment 2 of this invention. A flowchart showing an operation when restarting the hydrogen production operation of the hydrogen production apparatus according to the second embodiment of the present invention.

The first invention has an electrolyte membrane between an anode and a cathode, supplies a hydrogen-containing gas to the anode, and allows a current in a predetermined direction to flow between the anode and the cathode to purify hydrogen gas at the cathode. A power supply that allows current to flow between the anode and cathode, a reformer that reforms hydrocarbon-based raw materials to generate hydrogen-containing gas, and a reformer that produces hydrogen-containing gas. A CO reducer that reduces the concentration of carbon monoxide contained in the supplied hydrogen-containing gas, a raw material supply device that supplies raw materials to the reformer via the raw material supply flow path, a reformer, and a CO reducer. A heater for heating, a purified hydrogen gas flow path for supplying purified hydrogen gas to a hydrogen utilization device, and a refined hydrogen gas flow path on-off valve provided in the purified hydrogen gas flow path so that the purified hydrogen gas flow path can be opened and closed. A recirculation flow path that branches from the flow path on the upstream side of the purification hydrogen gas flow path on-off valve in the refined hydrogen gas flow path and joins the raw material supply flow path, and a recirculation flow path that can be opened and closed are provided in the recirculation flow path. It is a hydrogen production device provided with a recirculation flow path on-off valve and a controller. The controller operates the raw material supply device, the power supply, and the heater, respectively, so that the hydrogen production device operates to produce hydrogen. When the flow path on-off valve is closed and the refined hydrogen gas flow path on-off valve is open, and the hydrogen production operation of the hydrogen production device is stopped, the raw material supply and power supply are used. When each operation of the heater is stopped, the refined hydrogen gas flow path on-off valve is closed, and the hydrogen production operation is restarted, the refined hydrogen gas flow-off valve is closed before the raw material feeder is operated. It is characterized in that the power supply and the heater are operated in the state and the return flow path on-off valve is in the open state.

The hydrogen production device having the above configuration uses the hydrogen gas of the hydrogen-containing gas and the purified hydrogen gas remaining inside the hydrogen production device as a recirculation flow path and an electrochemical function as a hydrogen pump when the hydrogen production operation is restarted. The reformer and the CO reducer are heated by the heater while circulating by the device.

Therefore, since hydrogen gas is used as the heating gas of the reformer and the CO reducer, the temperature of the reformer is set to the temperature at which carbon precipitation occurs in the reformer when the temperature of the reformer and the CO reducer is raised. Since it is not necessary to operate the heater so as not to cause the problem, the start-up time when the heater is continuously operated and the hydrogen production operation is restarted can be shortened as compared with the conventional case. Therefore, it is possible to provide a hydrogen production apparatus having an improved operating rate.

In particular, in addition to the first invention, the second invention communicates with the purified hydrogen gas flow path on the upstream side of the purified hydrogen gas flow path on-off valve or the recirculation flow path on the upstream side of the recirculation flow path on-off valve. It is characterized by being provided with a hydrogen reservoir.

As a result, the purified hydrogen gas stored in the hydrogen storage until the hydrogen production device stops the hydrogen production operation is also a reflux flow path before the raw material supply device is operated when the hydrogen production operation is restarted. Since it can be circulated using hydrogen, the circulating flow rate of purified hydrogen gas can be increased compared to the case without a hydrogen storage, and the concentration of hydrogen in the circulating gas is higher than that without a hydrogen storage. Since it becomes high, even if the raw material remains in the raw material supply flow path and the reformer immediately before the purified hydrogen gas circulates, it becomes the raw material supply flow path before the reformer is heated to a high temperature. There is a high possibility that the raw materials remaining in the reformer can be discharged from the reformer, and the circulating flow rate of purified hydrogen gas as a heat medium increases, so that the temperature of the CO reducer rises faster, so hydrogen production operation The start-up time when restarting can be further shortened.

In the third invention, in particular, in addition to the second invention, an off-gas flow path for discharging a hydrogen-containing gas supplied to the anode that does not move to the cathode from the anode and an off-gas flow path can be opened and closed. Off-gas flow path opening and closing, which is provided in the off-gas flow path and maintains an open state when the hydrogen production device is operating hydrogen production, and maintains a closed state when the hydrogen production device is stopped in hydrogen production operation. A valve is provided, and when the controller restarts the hydrogen production operation, the off-gas flow path on-off valve is opened to operate the power supply and the heater.

As a result, when the hydrogen production operation is restarted, impurities other than hydrogen contained in the gas of the anode can be released to the outside using the off-gas flow path, and the impurities are accumulated in the anode to cause the electrochemical device. Performance deterioration can be suppressed.

When the purified hydrogen gas is circulated, a hydrogen-containing gas containing a large amount of impurities is released from the off-gas flow path to the outside, but the pressure of the purified hydrogen gas in the recirculation flow path is the purified hydrogen in the hydrogen storage. When the pressure drops below the gas pressure, the reflux channel is replenished with purified hydrogen gas for circulation from the hydrogen reservoir, so the amount of purified hydrogen gas stored in the hydrogen reservoir relative to the amount of gas released from the off-gas channel. If the amount is sufficient (the volume of the hydrogen reservoir is sufficient), there is no risk of running out of purified hydrogen gas for circulation.

The fourth invention is characterized in that, in particular, in the third invention, the heater is configured to burn the gas supplied from the off-gas flow path.

As a result, the gas discharged from the anode to the off-gas flow path can be effectively used as fuel for the heater, and the energy efficiency of the hydrogen production apparatus can be improved as compared with the case where this is not done.

A fifth invention has an electrolyte membrane between an anode and a cathode, supplies a hydrogen-containing gas to the anode, and allows a current in a predetermined direction to flow between the anode and the cathode to purify hydrogen gas at the cathode. A power supply that allows current to flow between the anode and cathode, a reformer that reforms hydrocarbon-based raw materials to generate hydrogen-containing gas, and a reformer that produces hydrogen-containing gas. A CO reducer that reduces the concentration of carbon monoxide contained in the supplied hydrogen-containing gas, a raw material supply device that supplies raw materials to the reformer via the raw material supply flow path, a reformer, and a CO reducer. A heater for heating, a purified hydrogen gas flow path for supplying purified hydrogen gas to a hydrogen utilization device, and a refined hydrogen gas flow path on-off valve provided in the purified hydrogen gas flow path so that the purified hydrogen gas flow path can be opened and closed. A recirculation flow path that branches from the flow path on the upstream side of the refined hydrogen gas flow path on-off valve in the refined hydrogen gas flow path and joins the raw material supply flow path, and a recirculation flow path that can be opened and closed are provided in the recirculation flow path. When the hydrogen production apparatus is operating hydrogen production by operating the raw material supply device, the power supply, and the heater, respectively, in the operation method of the hydrogen production apparatus provided with the return flow path on-off valve. When the closed state of the recirculation flow path on-off valve and the open state of the purified hydrogen gas flow path on-off valve are maintained and the hydrogen production operation of the hydrogen production device is stopped, the operation of the raw material supply device, the power supply, and the heater, respectively. When the refined hydrogen gas flow path on-off valve is closed and the hydrogen production operation is restarted, the refined hydrogen gas flow path on-off valve is closed and the recirculation flow path is opened and closed before the raw material feeder is operated. It is characterized in that the power supply and the heater are operated with the valve open.

When the hydrogen production apparatus operated by the above operation method restarts the hydrogen production operation, the hydrogen gas of the hydrogen-containing gas and the purified hydrogen gas remaining inside the hydrogen production apparatus is used as a recirculation flow path and a hydrogen pump. A functioning electrochemical device heats the reformer and the CO reducer with a heater while circulating.

Therefore, since hydrogen gas is used as the heating gas of the reformer and the CO reducer, the temperature of the reformer is set to the temperature at which carbon precipitation occurs in the reformer when the temperature of the reformer and the CO reducer is raised. Since it is not necessary to operate the heater so as not to cause the problem, the start-up time when the heater is continuously operated and the hydrogen production operation is restarted can be shortened as compared with the conventional case. Therefore, the operating rate of the hydrogen production apparatus can be improved.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. The present invention is not limited to the embodiments of the present invention.

(Embodiment 1)
FIG. 1 is a block diagram showing a configuration of a hydrogen production apparatus according to the first embodiment of the present invention. FIG. 2 is a flowchart showing an operation when restarting the hydrogen production operation of the hydrogen production apparatus according to the first embodiment of the present invention.

As shown in FIG. 1, the hydrogen production apparatus 100 of the present embodiment includes a hydrogen generation apparatus 10, a raw material supply device 13, a water supply device 14, an electrochemical device 20, a power source 30, and a raw material supply flow path. 40, water supply flow path 41, hydrogen-containing gas flow path 42, off-gas flow path 43, recirculation flow path 44, purified hydrogen gas flow path 45, off-gas flow path on-off valve 52, recirculation flow path on / off. A valve 53, a purified hydrogen gas flow path on-off valve 54, and a controller 80 are provided.

The hydrogen generator 10 includes a reformer 11, a heater 12, a reformer temperature detector 15, a CO reducer 16, and a CO reducer temperature detector 17.

The reformer 11 generates hydrogen-containing gas by a reforming reaction using raw materials and steam. In the present embodiment, the raw material used is city gas containing methane as a main component. As the reforming reaction of the present embodiment, a steam reforming reaction in which city gas and steam are reacted was used. A reforming catalyst (not shown) is mounted inside the reformer 11.

The CO reducer 16 reduces the concentration of carbon monoxide contained in the hydrogen-containing gas generated by the reformer 11 by a metamorphic reaction. A metamorphic catalyst (not shown) is mounted inside the CO reducer 16.

The heater 12 heats the reformer 11 and the CO reducer 16 by mixing and burning fuel and air. Further, as the fuel of the heater 12, city gas containing methane as a main component was used.

The reformer temperature detector 15 is a thermocouple that detects the temperature of the reforming catalyst mounted on the reformer 11.

The CO reducer temperature detector 17 is a thermistor that detects the temperature of the metamorphic catalyst mounted on the CO reducer 16.

The raw material supply device 13 is a gas pump that supplies city gas to the reformer 11 via the raw material supply flow path 40. The raw material supply device 13 is configured so that the gas in the raw material supply flow path 40 does not flow back through the raw material supply device 13 when the raw material supply operation is stopped.

The water supply device 14 is a water pump that supplies water to the reformer 11 via the water supply flow path 41.

The electrochemical device 20 includes an electrolyte membrane 21, an anode 22 arranged on one main surface of the electrolyte membrane 21, and a cathode 23 arranged on the other main surface of the electrolyte membrane 21.

The electrolyte membrane 21 is a polymer membrane that selectively transports (permeates) hydrogen ions.

The anode 22 is supplied to the anode electrode between the anode electrode, which is bonded to one main surface of the electrolyte membrane 21 and causes an oxidation reaction in which hydrogen dissociates into hydrogen ions and electrons, and the anode inlet and anode outlet. It is composed of an anode separator in which a flow path for a hydrogen-containing gas is formed.

The cathode 23 is bonded to the other main surface of the electrolyte membrane 21 to cause a reduction reaction in which hydrogen ions and electrons are combined to form hydrogen, and a purified hydrogen gas generated by the cathode electrode by the reduction reaction. It is composed of a cathode separator in which a flow path for purified hydrogen gas discharged to the cathode outlet is formed.

The power supply 30 is a DC power supply in which the potential of the anode 22 is made higher than the potential of the cathode 23 and a current is passed from the anode 22 to the cathode 23 via the electrolyte membrane 21. The positive terminal of the power supply 30 is electrically connected to the anode 22, and the negative terminal of the power supply 30 is electrically connected to the cathode 23.

The hydrogen-containing gas flow path 42 is a flow path that connects the outlet of the hydrogen generation device 10 and the anode inlet of the anode 22 to supply the hydrogen-containing gas generated by the hydrogen generation device 10 to the anode 22.

The off-gas flow path 43 is a flow path in which one end is connected to the anode outlet of the anode 22 and excess hydrogen-containing gas is discharged from the anode 22 to the outside.

The off-gas flow path on-off valve 52 is a solenoid valve provided on the off-gas flow path 43 to open and close the off-gas flow path 43.

The purified hydrogen gas flow path 45 is a flow path that connects the cathode outlet of the cathode 23 and the hydrogen utilization device 90 and supplies the purified hydrogen gas discharged from the cathode 23 to the hydrogen utilization device 90.

The purified hydrogen gas flow path on-off valve 54 is an electromagnetic valve provided on the purified hydrogen gas flow path 45 to open and close the purified hydrogen gas flow path 45.

The reflux flow path 44 is a flow path that branches from the flow path on the upstream side of the purified hydrogen gas flow path on-off valve 54 in the purified hydrogen gas flow path 45 and joins the raw material supply flow path 40.

The recirculation flow path on-off valve 53 is an electromagnetic valve provided on the recirculation flow path 44 to open and close the recirculation flow path 44.

The controller 80 controls the operation of the hydrogen production apparatus 100. The controller 80 includes a signal input / output unit (not shown), an arithmetic processing unit (not shown), and a storage unit (not shown) for storing a control program.

The hydrogen utilization device 90 is a tank for storing purified hydrogen gas supplied from the hydrogen production device 100.

The operation and operation of the hydrogen production apparatus 100 of the present embodiment configured as described above will be described below. In the following operation, the controller 80 uses the raw material supply device 13, the water supply device 14, the hydrogen generator 10, the power supply 30, the off-gas flow path on-off valve 52, the reflux flow path on-off valve 53, and purified hydrogen. This is done by controlling the gas flow path on-off valve 54.

When the hydrogen production apparatus 100 is operating hydrogen production, the recirculation flow path on-off valve 53 is in the closed state, the off-gas flow path on-off valve 52 and the purified hydrogen gas flow path on-off valve 54 are in the open state, respectively, and the raw materials are used. The feeder 13 supplies city gas to the reformer 11, the water supply 14 supplies water to the reformer 11, and the heater 12 burns the city gas to burn the reformer 11 and CO. The reducer 16 and the reducer 16 are heated respectively, the reformer 11 generates hydrogen-containing gas by the reforming reaction, and the CO reducer 16 is monoxide contained in the hydrogen-containing gas generated by the reformer 11. The concentration of carbon is reduced by a transformation reaction, the power supply 30 is passing a current from the anode 22 to the cathode 23 via the electrolyte membrane 21, and the electrochemical device 20 is a hydrogen-containing gas supplied to the anode 22. Therefore, purified hydrogen gas having a higher hydrogen purity than hydrogen-containing gas is generated at the cathode 23, and the purified hydrogen gas generated by the electrochemical device 20 is supplied to the hydrogen utilization device 90 via the purified hydrogen gas flow path 45. Has been done. The hydrogen-containing gas surplus at the anode 22 is discharged from the off-gas flow path 43.

When the hydrogen production operation of the hydrogen production apparatus 100 is stopped (finished), the controller 80 stops the current of the power supply 30, closes the purified hydrogen gas flow path on-off valve 54, and feeds the raw material supply device 13 and the water supply device 14. And the heater 12 are controlled respectively to stop the hydrogen-containing gas generation operation of the hydrogen generation device 10 and close the off-gas flow path on-off valve 52.

At this time, the recirculation flow path on-off valve 53 is temporarily opened to supply the raw material between the time when the raw material supply device 13, the water supply device 14, and the heater 12 are stopped and the time when the off-gas flow path on-off valve 52 is closed. The flow path 40, the reformer 11, and the CO reducer 16 may be purged with purified hydrogen gas, but the hydrogen gas to be circulated when the temperature of the reformer 11 and the CO reducer 16 is raised later is not insufficient. To do.

From the time when the hydrogen production apparatus 100 completes the stop operation of the hydrogen production operation to the time when the hydrogen production operation is restarted, the off-gas flow path on-off valve 52, the recirculation flow path on-off valve 53, and the purified hydrogen gas flow path on-off valve 54 Each closed state is maintained.

Therefore, while the hydrogen production apparatus 100 is stopped from the hydrogen production operation, the cathode 23, the recirculation flow path 44 on the cathode 23 side of the recirculation flow path on-off valve 53, and the purified hydrogen gas flow path on-off valve 54 Purified hydrogen gas having a pressure higher than that of atmospheric pressure remains in the purified hydrogen gas flow path 45 on the cathode 23 side.

Further, while the hydrogen production apparatus 100 is stopped from the hydrogen production operation, a part of the purified hydrogen gas of the cathode 23 passes through the electrolyte membrane 21 from the cathode 23, moves to the anode 22, and remains in the anode 22. The mixed gas (hydrogen-containing gas) is mixed with the existing hydrogen-containing gas, but since the off-gas flow path on-off valve 52 is closed, the gas flow path upstream of the off-gas flow path on-off valve 52 and the anode 22 are mixed. Stay in.

When the hydrogen production apparatus 100 starts the start-up operation, first, the controller 80 maintains the closed state of the purified hydrogen gas flow path on-off valve 54 and the closed state of the off-gas flow path on-off valve 52, and the reflux flow. The path on-off valve 53 is opened, and the purified hydrogen gas flow path 45 and the raw material supply flow path 40 are communicated with each other by the return flow path 44 (S101).

As a result, the purified hydrogen gas in the recirculation flow path 44 on the cathode 23 side of the recirculation flow path on-off valve 53 and the purified hydrogen gas in the purified hydrogen gas flow path 45 on the cathode 23 side of the recirculation flow path on-off valve 54. Passes through the recirculation flow path on-off valve 53 and diffuses into the recirculation flow path 44 on the raw material supply flow path 40 side of the recirculation flow path on-off valve 53.

Next, the power supply 30 is controlled to pass a current from the anode 22 to the cathode 23 via the electrolyte membrane 21, and the hydrogen gas contained in the mixed gas (hydrogen-containing gas) staying in the anode 22 is moved to the cathode 23. (S102).

At this time, the hydrogen gas that has moved to the cathode 23 is supplied to the reformer 11 through the reflux channel 44, and the hydrogen gas that has passed through the reformer 11 and the CO reducer 16 is supplied to the anode 22 (hydrogen). The gas circulates in the flow path connecting the reformer 11, the CO reducer 16, and the electrochemical device 20 in a ring shape).

Next, the controller 80 starts supplying the city gas and the combustion air to the heater 12, and also ignites the heater 12 to produce a mixed gas of the city gas and the combustion air in the heater 12. (S103), the reformer 11 and the CO reducer 16 are started to be heated by the combustion heat of the heater 12. The hydrogen gas heated when passing through the reformer 11 (which has taken heat from the reformer 11) heats the CO reducer 16 as it passes through the CO reducer 16.

Next, whether or not the temperature detected by the reformer temperature detector 15 is equal to or higher than the first temperature and the temperature detected by the CO reducer temperature detector 17 satisfies the condition of the second temperature or higher. Judgment (S104). Then, as a result of the determination, if the condition of S104 is not satisfied,
The determination of S104 is repeated until the condition is satisfied.

Here, the first temperature is a temperature at which a hydrogen-containing gas containing hydrogen having a concentration required for hydrogen production operation in the electrochemical device 20 is generated from the city gas by the reforming reaction, and is 600 ° C. in the present embodiment. And said. The second temperature is a temperature at which the concentration of carbon monoxide contained in the hydrogen-containing gas is sufficiently reduced by the metamorphism reaction, and is set to 200 ° C. in the present embodiment.

In S104, if the temperature detected by the reformer temperature detector 15 is the first temperature or higher and the temperature detected by the CO reducer temperature detector 17 satisfies the condition of the second temperature or higher, S104. Is branched to the Yes side, the reflux flow path on-off valve 53 is closed, the off-gas flow path on-off valve 52 is opened, and the power supply 30 is stopped (S105).

Next, the raw material supply device 13 is controlled to start the supply of city gas, and the water supply device 14 is controlled to start the water supply (S106).

Next, it is determined whether or not the first time has elapsed since the supply of city gas and water to the reformer 11 was started (S107). Then, if the first time has not passed since the supply of city gas and water to the reformer 11 was started, the determination of S107 is repeated until the first time has passed.

Here, the first time means that the anode 22 is sufficiently purged with the hydrogen-containing gas generated by the hydrogen generation device 10 (both the flow rate and the components of the hydrogen-containing gas supplied from the hydrogen generation device 10 to the anode 22 are electric. It is the time required for the chemical device 20 to be in a state suitable for starting the operation), and in the present embodiment, the first time is set to 2 minutes.

When the first hour has passed since the supply of city gas and water to the reformer 11 was started, S107 was branched to the Yes side, and the purified hydrogen gas flow path on-off valve 54 was opened (S108).

Next, the power supply 30 is controlled to pass a current from the anode 22 to the cathode 23 via the electrolyte membrane 21, and the start-up operation is completed (S109).

After the start-up operation is completed, the operation shifts to the hydrogen production operation. The hydrogen production operation is an operation in which the purified hydrogen gas purified from the hydrogen-containing gas by the electrochemical device 20 is stably and continuously supplied to the hydrogen utilization device 90. The controller 80 operates the raw material supply device 13 and the power supply 30 so that the amount of hydrogen purified by the electrochemical device 20 is sufficient for the amount required by the hydrogen utilization device 92.

As described above, the hydrogen production apparatus 100 of the present embodiment has the electrolyte membrane 21 between the anode 22 and the cathode 23, supplies the hydrogen-containing gas to the anode 22, and has the anode 22 and the cathode 23. A current in a predetermined direction (a current flowing from the anode 22 to the cathode 23 via the electrolyte membrane 21) is passed between them, so that a current in the predetermined direction is passed through the electrochemical device 20 that generates purified hydrogen gas at the cathode 23. The concentration of carbon monoxide contained in the power supply 30, the reformer 11 that reforms the hydrocarbon-based raw material to generate hydrogen-containing gas, and the hydrogen-containing gas generated by the reformer 11 and supplied to the anode 22. The CO reducer 16 for reducing the amount of water, the raw material supply device 13 for supplying the raw material to the reformer 11 via the raw material supply flow path 40, the heater 12 for heating the reformer 11 and the CO reducer 16, and purification. A purified hydrogen gas flow path 45 for supplying hydrogen gas to the hydrogen utilization device 90, a purified hydrogen gas flow path on-off valve 54 provided in the purified hydrogen gas flow path 45 so that the purified hydrogen gas flow path 45 can be opened and closed, and a valve 54. The recirculation flow path 44 in the refined hydrogen gas flow path 45, which branches from the flow path on the upstream side of the purified hydrogen gas flow path on-off valve 54 and joins the raw material supply flow path 40, and the recirculation flow path 44 can be opened and closed. The hydrogen production apparatus 100 is provided on the road 44 and includes a recirculation flow path on-off valve 53 and a controller 80.

Then, when the controller 80 operates the raw material supply device 13, the power supply 30, and the heater 12, respectively, and the hydrogen production device 100 operates the hydrogen production operation, the recirculation flow path on-off valve 53 is closed. When the state and the open state of the purified hydrogen gas flow path on-off valve 54 are maintained and the hydrogen production operation of the hydrogen production apparatus 100 is stopped, the operations of the raw material supply device 13, the power supply 30, and the heater 12 are stopped. At the same time, when the purified hydrogen gas flow path on-off valve 54 is closed and the hydrogen production operation is restarted, the purified hydrogen gas flow path on-off valve 54 is closed and the recirculation flow path is before the raw material supply device 13 is operated. The on-off valve 53 is open, and the power supply 30 and the heater 12 are operated.

When the hydrogen production device 100 having the above configuration resumes the hydrogen production operation, the hydrogen gas of the hydrogen-containing gas and the purified hydrogen gas remaining inside the hydrogen production device 100 functions as a recirculation flow path 44 and a hydrogen pump. In the heater 12, the reformer 11 and the CO reducer 16 are supplied with city gas and water to the reformer 11 to undergo a reforming reaction in the reformer 11 while being circulated by the electrochemical device 20. The temperature is raised to a suitable temperature.

At this time, hydrogen gas is used as the temperature raising gas of the reformer 11 and the CO reducer 16 instead of city gas, and hydrogen gas exists around the reforming catalyst of the reformer 11 at the time of temperature rise. Therefore, even if the temperature of the reforming catalyst becomes high, the deterioration of the reforming catalyst due to carbon precipitation is suppressed. It is not necessary to operate the heater 12 so that the temperature at which carbon precipitation occurs in the pawn 11 is not reached.

Therefore, when the heater 12 is continuously operated and the hydrogen production operation is restarted, the start-up time can be shortened as compared with the conventional case, and the operating rate can be improved as compared with the conventional case.

In the hydrogen production device 100 of the present embodiment, the hydrogen production device 100 is provided in the off-gas flow path 43 for discharging the hydrogen-containing gas supplied to the anode 22 that does not move to the cathode 23 from the anode 22. The open state is maintained (the off-gas flow path 43 is opened) when the hydrogen production operation is being performed, and the closed state is maintained (the off-gas flow path 43 is closed) when the hydrogen production device 100 is stopped from the hydrogen production operation. The off-gas flow path on-off valve 52 is provided, but when the hydrogen production operation is restarted (the temperature of the reformer 11 and the CO reducer 16 is raised), the controller 80 closes the off-gas flow path on-off valve 52. Since the power supply 30 and the heater 12 are operated while maintaining the state, the hydrogen gas circulated by the recirculation flow path 44 and the electrochemical device 20 functioning as a hydrogen pump flows out from the off-gas flow path 43. It can be suppressed from decreasing.

In the present embodiment, the hydrogen tank is used as the hydrogen utilization device 90, but a fuel cell that generates electricity by using hydrogen and oxygen in the air may be used instead of the hydrogen tank.

Further, the gas discharged from the off-gas flow path 43 may be burned by the heater 12. When the gas discharged from the off-gas flow path 43 is burned by the heater 12, city gas is supplied to the heater 12 when the off-gas flow path on-off valve 52 is closed and the heater 12 needs to be heated. Further, when the amount of heating is insufficient only by burning the gas discharged from the off-gas flow path 43, the shortage is supplemented with city gas.

Further, in order to prevent the electrochemical device 20 from being deteriorated by heat, the cooling water circulating when the hydrogen production apparatus 100 operates may be configured to exchange heat with the electrochemical device 20.

(Embodiment 2)
FIG. 3 is a block diagram showing a configuration of a hydrogen production apparatus according to a second embodiment of the present invention. FIG. 4 is a flowchart showing an operation when restarting the hydrogen production operation of the hydrogen production apparatus according to the second embodiment of the present invention.

In the hydrogen production apparatus 101 of the present embodiment, the same reference numerals are given to the same configurations as the hydrogen production apparatus 100 of the first embodiment shown in FIG.

As shown in FIG. 3, the hydrogen production apparatus 101 of the present embodiment includes a hydrogen generation apparatus 10, a raw material supply device 13, a water supply device 14, an electrochemical device 20, a power source 30, and a raw material supply flow path. 40, water supply flow path 41, hydrogen-containing gas flow path 42, off-gas flow path 43, recirculation flow path 44, purified hydrogen gas flow path 45, off-gas flow path on-off valve 52, recirculation flow path on / off. It includes a valve 53, a purified hydrogen gas flow path on-off valve 54, a controller 81, and a hydrogen reservoir 91.

The hydrogen generator 10 includes a reformer 11, a heater 12, a reformer temperature detector 15, a CO reducer 16, and a CO reducer temperature detector 17.

The reformer 11 generates hydrogen-containing gas by a reforming reaction using raw materials and steam. In the present embodiment, the raw material used is city gas containing methane as a main component. As the reforming reaction of the present embodiment, a steam reforming reaction in which city gas and steam are reacted was used. A reforming catalyst (not shown) is mounted inside the reformer 11.

The CO reducer 16 reduces the concentration of carbon monoxide contained in the hydrogen-containing gas generated by the reformer 11 by a metamorphic reaction. A metamorphic catalyst (not shown) is mounted inside the CO reducer 16.

The heater 12 heats the reformer 11 and the CO reducer 16 by mixing and burning fuel and air. Further, as the fuel of the heater 12, at least one of the city gas and the hydrogen-containing gas discharged from the electrochemical device 20 is used.

The reformer temperature detector 15 is a thermocouple that detects the temperature of the reforming catalyst mounted on the reformer 11.

The CO reducer temperature detector 17 is a thermistor that detects the temperature of the metamorphic catalyst mounted on the CO reducer 16.

The raw material supply device 13 is a gas pump that supplies city gas to the reformer 11 via the raw material supply flow path 40. The raw material supply device 13 is configured so that the gas in the raw material supply flow path 40 does not flow back through the raw material supply device 13 when the raw material supply operation is stopped.

The water supply device 14 is a water pump that supplies water to the reformer 11 via the water supply flow path 41.

The electrochemical device 20 includes an electrolyte membrane 21, an anode 22 arranged on one main surface of the electrolyte membrane 21, and a cathode 23 arranged on the other main surface of the electrolyte membrane 21.

The electrolyte membrane 21 is a polymer membrane that selectively transports (permeates) hydrogen ions.

The anode 22 is supplied to the anode electrode between the anode electrode, which is bonded to one main surface of the electrolyte membrane 21 and causes an oxidation reaction in which hydrogen dissociates into hydrogen ions and electrons, and the anode inlet and anode outlet. It is composed of an anode separator in which a flow path for a hydrogen-containing gas is formed.

The cathode 23 is bonded to the other main surface of the electrolyte membrane 21 to cause a reduction reaction in which hydrogen ions and electrons are combined to form hydrogen, and a purified hydrogen gas generated by the cathode electrode by the reduction reaction. It is composed of a cathode separator in which a flow path for purified hydrogen gas discharged to the cathode outlet is formed.

The power supply 30 is a DC power supply in which the potential of the anode 22 is made higher than the potential of the cathode 23 and a current is passed from the anode 22 to the cathode 23 via the electrolyte membrane 21. The positive terminal of the power supply 30 is electrically connected to the anode 22, and the negative terminal of the power supply 30 is electrically connected to the cathode 23.

The hydrogen-containing gas flow path 42 is a flow path that connects the outlet of the hydrogen generation device 10 and the anode inlet of the anode 22 to supply the hydrogen-containing gas generated by the hydrogen generation device 10 to the anode 22.

The off-gas flow path 43 is a flow path in which one end is connected to the anode outlet of the anode 22 and excess hydrogen-containing gas is supplied from the anode 22 to the heater 12.

The off-gas flow path on-off valve 52 is a solenoid valve provided on the off-gas flow path 43 to open and close the off-gas flow path 43.

The purified hydrogen gas flow path 45 is a flow path that connects the cathode outlet of the cathode 23 and the hydrogen utilization device 92 and supplies the purified hydrogen gas discharged from the cathode 23 to the hydrogen utilization device 92.

The purified hydrogen gas flow path on-off valve 54 is an electromagnetic valve provided on the purified hydrogen gas flow path 45 to open and close the purified hydrogen gas flow path 45.

The reflux flow path 44 is a flow path that branches from the flow path on the upstream side of the purified hydrogen gas flow path on-off valve 54 in the purified hydrogen gas flow path 45 and joins the raw material supply flow path 40.

The recirculation flow path on-off valve 53 is an electromagnetic valve provided on the recirculation flow path 44 to open and close the recirculation flow path 44.

The controller 81 controls the operation of the hydrogen production apparatus 101. The controller 81 includes a signal input / output unit (not shown), an arithmetic processing unit (not shown), and a storage unit (not shown) for storing a control program.

The hydrogen reservoir 91 is a container having a predetermined capacity communicating with the recirculation flow path 44 on the upstream side of the recirculation flow path on-off valve 53, and is in the recirculation flow path 44 on the cathode 23 side of the recirculation flow path on-off valve 53. Purified hydrogen gas is stored in the hydrogen reservoir 91 so that there is no pressure difference when the pressure of the purified hydrogen gas is higher than the pressure of the purified hydrogen gas in the hydrogen reservoir 91, and the cathode 23 is more than the recirculation flow path on-off valve 53. The purified hydrogen gas in the hydrogen reservoir 91 is placed in the reflux channel 44 so that the pressure difference disappears when the pressure of the purified hydrogen gas in the return channel 44 on the side is lower than the pressure of the purified hydrogen gas in the hydrogen reservoir 91. Supply to.

The hydrogen utilization device 92 is a fuel cell that generates electricity by reacting hydrogen (purified hydrogen gas) supplied from the purified hydrogen gas flow path 45 with oxygen in the air.

The operation and operation of the hydrogen production apparatus 101 of the present embodiment configured as described above will be described below. In the following operation, the controller 81 uses the raw material supply device 13, the water supply device 14, the hydrogen generator 10, the power supply 30, the off-gas flow path on-off valve 52, the reflux flow path on-off valve 53, and purified hydrogen. This is done by controlling the gas flow path on-off valve 54.

When the hydrogen production apparatus 101 is operating hydrogen production, the recirculation flow path on-off valve 53 is in the closed state, the off-gas flow path on-off valve 52 and the purified hydrogen gas flow path on-off valve 54 are in the open state, respectively, and the raw materials are used. The supply device 13 supplies city gas to the reformer 11, the water supply device 14 supplies water to the reformer 11, and the heater 12 is discharged from the anode 22 to the off-gas flow path 43. The hydrogen-containing gas is burned to heat the reformer 11 and the CO reducer 16, respectively. The reformer 11 generates hydrogen-containing gas by a reforming reaction, and the CO-reducer 16 is a reformer. The concentration of carbon monoxide contained in the hydrogen-containing gas generated in No. 11 is reduced by a transformation reaction, and the power supply 30 sends a current from the anode 22 to the cathode 23 via the electrolyte membrane 21 and is electrochemical. The device 20 generates purified hydrogen gas having a higher hydrogen purity than the hydrogen-containing gas at the cathode 23 from the hydrogen-containing gas supplied to the anode 22, and the purified hydrogen gas generated by the electrochemical device 20 is purified hydrogen. It is supplied to the hydrogen utilization device 92 via the gas flow path 45. Further, the hydrogen reservoir 91 stores purified hydrogen gas.

When the hydrogen production operation of the hydrogen production apparatus 101 is stopped (finished), the controller 81 stops the current of the power supply 30, closes the purified hydrogen gas flow path on-off valve 54, and closes the raw material supply device 13 and the water supply device 14. And the heater 12 are controlled respectively to stop the hydrogen-containing gas generation operation of the hydrogen generation device 10 and close the off-gas flow path on-off valve 52.

At this time, between the time when the raw material supply device 13 and the water supply device 14 are stopped and the time when the off-gas flow path on-off valve 52 is closed, the reflux flow path on-off valve 53 is temporarily opened to form the raw material supply flow path 40. The reformer 11 and the CO reducer 16 may be purged with purified hydrogen gas, but the hydrogen gas to be circulated when the temperature rise of the reformer 11 and the CO reducer 16 is not insufficient.

From the time when the hydrogen production apparatus 101 completes the stop operation of the hydrogen production operation to the time when the hydrogen production operation is restarted, the off-gas flow path on-off valve 52, the recirculation flow path on-off valve 53, and the purified hydrogen gas flow path on-off valve 54 Each closed state is maintained.

Therefore, while the hydrogen production apparatus 101 is stopped from the hydrogen production operation, the cathode 23, the recirculation flow path 44 on the cathode 23 side of the recirculation flow path on-off valve 53, the inside of the hydrogen storage 91, and the purified hydrogen gas. Purified hydrogen gas having a pressure higher than that of atmospheric pressure remains in the purified hydrogen gas flow path 45 on the cathode 23 side of the flow path on-off valve 54.

Further, while the hydrogen production apparatus 101 is stopped from the hydrogen production operation, a part of the purified hydrogen gas of the cathode 23 passes through the electrolyte membrane 21 from the cathode 23, moves to the anode 22, and remains in the anode 22. The mixed gas (hydrogen-containing gas) is mixed with the existing hydrogen-containing gas, but since the off-gas flow path on-off valve 52 is closed, the gas flow path upstream of the off-gas flow path on-off valve 52 and the anode 22 are mixed. Stay in.

When the hydrogen production apparatus 101 starts the start-up operation, first, the controller 81 opens the off-gas flow path on-off valve 52 and the return flow path on-off valve 53 while maintaining the closed state of the purified hydrogen gas flow path on-off valve 54. Each is opened, and the purified hydrogen gas flow path 45 and the raw material supply flow path 40 are communicated with each other by the reflux flow path 44 (S201).

As a result, the purified hydrogen gas in the recirculation flow path 44 on the cathode 23 side of the recirculation flow path on-off valve 53, the purified hydrogen gas in the hydrogen reservoir 91, and the purification of the cathode 23 side of the purified hydrogen gas flow path on-off valve 54. The purified hydrogen gas in the hydrogen gas flow path 45 passes through the recirculation flow path on-off valve 53 and diffuses into the recirculation flow path 44 on the raw material supply flow path 40 side of the recirculation flow path on-off valve 53.

Further, the hydrogen-containing gas in the off-gas flow path 43 on the anode 22 side of the off-gas flow path on-off valve 52 passes through the off-gas flow path on-off valve 52 and flows off-gas on the heater 12 side of the off-gas flow path on-off valve 52. It diffuses in the road 43.

Next, the power supply 30 is controlled to pass a current from the anode 22 to the cathode 23 via the electrolyte membrane 21, and the hydrogen gas contained in the mixed gas (hydrogen-containing gas) staying in the anode 22 is moved to the cathode 23. (S202). Further, the controller 81 starts supplying combustion air to the heater 12.

At this time, the hydrogen gas that has moved to the cathode 23 is supplied to the reformer 11 through the reflux channel 44, and the hydrogen gas that has passed through the reformer 11 and the CO reducer 16 is supplied to the anode 22 (hydrogen). The gas circulates in the flow path connecting the reformer 11, the CO reducer 16, and the electrochemical device 20 in a ring shape). Further, of the hydrogen-containing gas supplied to the anode 22, the residual hydrogen-containing gas that could not move to the cathode 23 is supplied from the anode 22 to the heater 12 through the off-gas flow path 43.

Then, when the pressure of the purified hydrogen gas in the recirculation flow path 44 on the cathode 23 side of the recirculation flow path on-off valve 53 becomes lower than the pressure of the purified hydrogen gas in the hydrogen storage device 91, hydrogen is stored so that the pressure difference disappears. The purified hydrogen gas in the vessel 91 is supplied into the recirculation flow path 44.

Next, the controller 81 ignites the heater 12 to burn the mixed gas of the hydrogen-containing gas supplied from the off-gas flow path 43 and the combustion air in the heater 12, and the heater 12 causes the heater 12. Heating of the reformer 11 and the CO reducer 16 by the heat of combustion is started (S203). The hydrogen gas heated when passing through the reformer 11 (which has taken heat from the reformer 11) heats the CO reducer 16 as it passes through the CO reducer 16.

Next, whether or not the temperature detected by the reformer temperature detector 15 is equal to or higher than the third temperature and the temperature detected by the CO reducer temperature detector 17 satisfies the condition of the fourth temperature or higher. Judgment (S204). Then, as a result of the determination, if the condition of S204 is not satisfied, the determination of S204 is repeated until the condition is satisfied.

Here, the third temperature is a temperature at which a hydrogen-containing gas containing hydrogen having a concentration required for hydrogen production operation in the electrochemical device 20 is generated from the city gas by the reforming reaction, and is 610 ° C. in the present embodiment. And said. The fourth temperature is a temperature at which the concentration of carbon monoxide contained in the hydrogen-containing gas is sufficiently reduced by the transformation reaction, and is set to 210 ° C. in the present embodiment.

In S204, if the temperature detected by the reformer temperature detector 15 is the third temperature or higher and the temperature detected by the CO reducer temperature detector 17 satisfies the condition of the fourth temperature or higher, S204 Is branched to the Yes side, the return flow path on-off valve 53 is closed, and the power supply 30 is stopped (S205).

Next, the raw material supply device 13 is controlled to start the supply of city gas, and the water supply device 14 is controlled to start the supply of water (S206).

Next, it is determined whether or not the second time has elapsed since the supply of city gas and water to the reformer 11 was started (S207). Then, if the second time has not elapsed since the supply of city gas and water to the reformer 11 was started, the determination of S207 is repeated until the second time elapses.

Here, the second time means that the anode 22 is sufficiently purged with the hydrogen-containing gas generated by the hydrogen generation device 10 (both the flow rate and the components of the hydrogen-containing gas supplied from the hydrogen generation device 10 to the anode 22 are electric. It is the time required for the chemical device 20 to be in a state suitable for starting the operation), and in the present embodiment, the second time is set to 1 minute.

When the second time elapses from the start of the supply of city gas and water to the reformer 11, S207 is branched to the Yes side, and the purified hydrogen gas flow path on-off valve 54 is opened (S208).

Next, the power supply 30 is controlled to pass a current through the electrochemical device 20, and the start-up operation is completed. (S209)
After the start-up operation is completed, the operation shifts to the hydrogen production operation. The hydrogen production operation is an operation in which the purified hydrogen gas purified from the hydrogen-containing gas by the electrochemical device 20 is stably and continuously supplied to the hydrogen utilization device 92. The controller 81 operates the raw material supply device 13 and the power supply 30 so that the amount of hydrogen purified by the electrochemical device 20 is sufficient for the amount required by the hydrogen utilization device 92.

As described above, the hydrogen production apparatus 101 of the present embodiment has the electrolyte membrane 21 between the anode 22 and the cathode 23, supplies the hydrogen-containing gas to the anode 22, and has the anode 22 and the cathode 23. A current in a predetermined direction (a current flowing from the anode 22 to the cathode 23 via the electrolyte membrane 21) is passed between them, so that a current in the predetermined direction is passed through the electrochemical device 20 that generates purified hydrogen gas at the cathode 23. The concentration of carbon monoxide contained in the power supply 30, the reformer 11 that reforms the hydrocarbon-based raw material to generate hydrogen-containing gas, and the hydrogen-containing gas generated by the reformer 11 and supplied to the anode 22. The CO reducer 16 for reducing the amount of water, the raw material supply device 13 for supplying the raw material to the reformer 11 via the raw material supply flow path 40, the heater 12 for heating the reformer 11 and the CO reducer 16, and purification. A purified hydrogen gas flow path 45 for supplying hydrogen gas to the hydrogen utilization device 92, a purified hydrogen gas flow path on-off valve 54 provided in the purified hydrogen gas flow path 45 so that the purified hydrogen gas flow path 45 can be opened and closed, and a valve 54. The recirculation flow path 44 in the refined hydrogen gas flow path 45, which branches from the flow path on the upstream side of the purified hydrogen gas flow path on-off valve 54 and joins the raw material supply flow path 40, and the recirculation flow path 44 can be opened and closed. The hydrogen production apparatus 101 is provided on the road 44 and includes a recirculation flow path on-off valve 53 and a controller 81.

Then, when the controller 81 operates the raw material supply device 13, the power supply 30, and the heater 12, respectively, and the hydrogen production device 101 is in the hydrogen production operation, the recirculation flow path on-off valve 53 is closed. When the state and the open state of the purified hydrogen gas flow path on-off valve 54 are maintained and the hydrogen production operation of the hydrogen production apparatus 100 is stopped, the operations of the raw material supply device 13, the power supply 30, and the heater 12 are stopped. At the same time, when the purified hydrogen gas flow path on-off valve 54 is closed and the hydrogen production operation is restarted, the purified hydrogen gas flow path on-off valve 54 is closed and the recirculation flow path is before the raw material supply device 13 is operated. The on-off valve 53 is open, and the power supply 30 and the heater 12 are operated.

When the hydrogen production apparatus 101 having the above configuration resumes the hydrogen production operation, the hydrogen gas of the hydrogen-containing gas and the purified hydrogen gas remaining inside the hydrogen production apparatus 101 due to the previous hydrogen production operation is recirculated through the recirculation flow path. The reformer 11 and the CO reducer 16 are supplied to the reformer 11 by the heater 12 to reform the reformer 11 while being circulated by the 44 and the electrochemical device 20 functioning as a hydrogen pump. The temperature is raised to a temperature suitable for the reforming reaction in the vessel 11.

At this time, hydrogen gas is used as the temperature raising gas of the reformer 11 and the CO reducer 16 instead of city gas, and hydrogen gas exists around the reforming catalyst of the reformer 11 at the time of temperature rise. Therefore, even if the temperature of the reforming catalyst becomes high, the deterioration of the reforming catalyst due to carbon precipitation is suppressed. It is not necessary to operate the heater 12 so that the temperature at which carbon precipitation occurs in the pawn 11 is not reached.

Therefore, when the heater 12 is continuously operated and the hydrogen production operation is restarted, the start-up time can be shortened as compared with the conventional case, and the operating rate can be improved as compared with the conventional case.

Further, the hydrogen production apparatus 101 of the present embodiment is further provided with a hydrogen storage device 91 communicating with the recirculation flow path 44 on the upstream side of the recirculation flow path on-off valve 53.

As a result, the purified hydrogen gas stored in the hydrogen storage container 91 before the hydrogen production apparatus 101 stops the hydrogen production operation is also before the raw material supply device 13 is operated when the hydrogen production operation is restarted. Since it can be circulated using the recirculation flow path 44, the circulating flow rate of the purified hydrogen gas can be increased as compared with the case without the hydrogen storage 91, and the circulation can be performed as compared with the case without the hydrogen storage 91. Since the hydrogen concentration of the gas becomes high, the reformer 11 is heated to a high temperature immediately before the purified hydrogen gas circulates, even if the raw material remains in the raw material supply flow path 40 and the reformer 11. There is a high possibility that the raw materials remaining in the raw material supply flow path 40 and the reformer 11 can be discharged from the reformer 11, and the circulating flow rate of purified hydrogen gas as a heat medium increases, thereby reducing CO. Since the temperature of the vessel 16 rises faster, the start-up time when restarting the hydrogen production operation can be further shortened.

In the present embodiment, the hydrogen reservoir 91 is communicated with the reflux channel 44 on the upstream side of the reflux channel on-off valve 53, but the present invention is not limited to this, and the hydrogen reservoir 91 is connected to the purified hydrogen gas flow. It may be communicated with the purified hydrogen gas flow path 45 on the upstream side of the path on-off valve 54.

Further, the hydrogen production apparatus 101 of the present embodiment has an off-gas flow path 43 for discharging the hydrogen-containing gas supplied to the anode 22 that does not move to the cathode 23 from the anode 22 to the heater 12, and an off-gas. The flow path 43 is provided in the off-gas flow path 43 so as to be openable and closable, and is maintained in an open state when the hydrogen production device 101 is in the hydrogen production operation, and when the hydrogen production device 101 is stopped in the hydrogen production operation. It is provided with an off-gas flow path on-off valve 52 that maintains a closed state, and when the controller 81 resumes the hydrogen production operation, the off-gas flow path on-off valve 52 is opened and the power supply 30 and the heater 12 are turned on. It is characterized by operating.

As a result, when the hydrogen production operation is restarted, impurities other than hydrogen contained in the gas of the anode 22 can be discharged to the heater 12 using the off-gas flow path 43, so that electricity due to the accumulation of impurities in the anode 22 Deterioration of performance of the chemical device 20 can be suppressed.

When the hydrogen gas is circulated, the hydrogen-containing gas containing a large amount of impurities is released from the off-gas flow path 43 to the heater 12, but the pressure of the purified hydrogen gas in the return flow path 44 is the hydrogen reservoir 91. When the pressure drops below the pressure of the purified hydrogen gas inside, the purified hydrogen gas for circulation is replenished from the hydrogen storage 91 to the recirculation flow path 44, so that the amount of gas discharged from the off-gas flow path 43 to the heater 12 is relative. If the amount of purified hydrogen gas stored in the hydrogen reservoir 91 is set to a sufficient amount (the volume of the hydrogen reservoir 91 is set to a sufficient volume), there is no possibility that the purified hydrogen gas for circulation will be insufficient.

Further, since the heater 12 is configured to burn the gas supplied from the off-gas flow path 43, the gas discharged from the anode 22 to the off-gas flow path 43 can be effectively used as fuel for the heater 12. The energy efficiency of the hydrogen production apparatus 101 can be improved as compared with the case where this is not done.

Further, in order to prevent the electrochemical device 20 from being deteriorated by heat, the cooling water circulating when the hydrogen production apparatus 101 operates may be configured to exchange heat with the electrochemical device 20.

Since the present invention can shorten the start-up time of the hydrogen production apparatus when restarting the hydrogen production operation, a hydrogen-containing gas is generated using a reformer and a CO-reducer, and electrochemistry is performed from the hydrogen-containing gas. A hydrogen production device that produces purified hydrogen gas with high hydrogen purity using a device, and is particularly applicable to applications where operation and shutdown are repeated.

10 Hydrogen generator 11 Reformer 12 Heater 13 Raw material supply 14 Water supply 15 Reformer Temperature detector 16 CO reducer 17 CO reducer Temperature detector 20 Electrochemical device 21 Electrolyte membrane 22 Anode 23 Cone 30 Power supply 40 Raw material supply flow path 41 Water supply flow path 42 Hydrogen-containing gas flow path 43 Off-gas flow path 44 Circulation flow path 45 Purified hydrogen gas flow path 52 Off-gas flow path on-off valve 53 Recirculation flow path on-off valve 54 Purified hydrogen gas flow-off valve 80 Controller 81 Controller 90 Hydrogen utilization equipment 91 Hydrogen storage 92 Hydrogen utilization equipment 100 Hydrogen production equipment 101 Hydrogen production equipment

Claims (5)

A purified hydrogen gas is generated at the cathode by having an electrolyte film between the anode and the cathode, supplying a hydrogen-containing gas to the anode, and passing a current in a predetermined direction between the anode and the cathode. Electrochemical devices and
A power source that allows the current to flow between the anode and the cathode,
A reformer that reforms a hydrocarbon-based raw material to generate the hydrogen-containing gas,
A CO reducer that reduces the concentration of carbon monoxide contained in the hydrogen-containing gas generated by the reformer and supplied to the anode, and
A raw material supply device that supplies the raw material to the reformer via the raw material supply flow path,
A heater that heats the reformer and the CO reducer,
A purified hydrogen gas flow path for supplying the purified hydrogen gas to a hydrogen utilization device, and
A purified hydrogen gas flow path on-off valve provided in the purified hydrogen gas flow path so that the purified hydrogen gas flow path can be opened and closed.
A reflux flow path that branches from a flow path on the upstream side of the purified hydrogen gas flow path on-off valve in the purified hydrogen gas flow path and joins the raw material supply flow path.
A reflux flow path on-off valve provided in the reflux flow path so that the return flow path can be opened and closed,
A hydrogen production device equipped with a controller,
The controller
When the hydrogen production apparatus is operating hydrogen production by operating the raw material supply device, the power supply, and the heater, respectively, the closed state of the reflux flow path on-off valve and the purified hydrogen gas flow. Keep the road on-off valve open,
When the hydrogen production operation of the hydrogen production apparatus is stopped, the operations of the raw material supply device, the power supply, and the heater are stopped, and the purified hydrogen gas flow path on-off valve is closed.
When the hydrogen production operation is restarted, the purified hydrogen gas flow path on-off valve is in the closed state and the reflux flow path on-off valve is in the open state before the raw material supply device is operated, and the power supply and the heater are used. A hydrogen production device characterized by operating. The claim is characterized by comprising a hydrogen reservoir communicating with the purified hydrogen gas flow path on the upstream side of the purified hydrogen gas flow path on-off valve or the recirculation flow path on the upstream side of the recirculation flow path on-off valve. The hydrogen production apparatus according to 1. An off-gas flow path for discharging the hydrogen-containing gas supplied to the anode, which does not move to the cathode, from the anode.
When the off-gas flow path is provided so as to be openable and closable, the hydrogen production apparatus is maintained in an open state when the hydrogen production apparatus is in operation, and the hydrogen production apparatus is stopped in the hydrogen production operation. Is equipped with an off-gas flow path on-off valve, which keeps it closed,
The hydrogen production apparatus according to claim 2, wherein the controller operates the power source and the heater by opening the off-gas flow path on-off valve when the hydrogen production operation is restarted. .. The hydrogen production apparatus according to claim 3, wherein the heater is configured to burn the gas supplied from the off-gas flow path. A purified hydrogen gas is generated at the cathode by having an electrolyte film between the anode and the cathode, supplying a hydrogen-containing gas to the anode, and passing a current in a predetermined direction between the anode and the cathode. Electrochemical devices and
A power source that allows the current to flow between the anode and the cathode,
A reformer that reforms a hydrocarbon-based raw material to generate the hydrogen-containing gas,
A CO reducer that reduces the concentration of carbon monoxide contained in the hydrogen-containing gas generated by the reformer and supplied to the anode, and
A raw material supply device that supplies the raw material to the reformer via the raw material supply flow path,
A heater that heats the reformer and the CO reducer,
A purified hydrogen gas flow path for supplying the purified hydrogen gas to a hydrogen utilization device, and
A purified hydrogen gas flow path on-off valve provided in the purified hydrogen gas flow path so that the purified hydrogen gas flow path can be opened and closed.
A reflux flow path that branches from a flow path on the upstream side of the purified hydrogen gas flow path on-off valve in the purified hydrogen gas flow path and joins the raw material supply flow path.
It is a method of operating a hydrogen production apparatus provided with a reflux channel on-off valve provided in the reflux channel so that the reflux channel can be opened and closed.
When the hydrogen production apparatus is operating hydrogen production by operating the raw material supply device, the power supply, and the heater, respectively, the closed state of the reflux flow path on-off valve and the purified hydrogen gas flow. Keep the road on-off valve open,
When the hydrogen production operation of the hydrogen production apparatus is stopped, the operations of the raw material supply device, the power supply, and the heater are stopped, and the purified hydrogen gas flow path on-off valve is closed.
When the hydrogen production operation is restarted, the purified hydrogen gas flow path on-off valve is in the closed state and the reflux flow path on-off valve is in the open state before the raw material supply device is operated, and the power supply and the heater are used. A method of operating a hydrogen production apparatus, which comprises operating a hydrogen production apparatus.

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