JP6574893B2 - Hydrogen leak prevention system, hydrogen leak prevention method hydrogen production system, power storage system - Google Patents

Description

  The present invention relates to a hydrogen leakage prevention system, a hydrogen leakage prevention method, a hydrogen production system, and a power storage system.

  In recent years, renewable energy such as solar power, wind power, and geothermal heat has been introduced from the viewpoints of environmental issues such as depletion of fossil fuels and global warming due to the release of carbon dioxide into the atmosphere, and energy security. Has been promoted. As secondary energy, hydrogen energy has attracted attention from the viewpoint of storage and transportation. Currently, hydrogen production methods mainly use fossil fuel reforming methods in terms of cost and technology.

  In addition, the introduction of renewable energy has been increasing in recent years, but due to its characteristics, there is a problem that it is difficult to arbitrarily adjust the amount of power generation so as to respond to output stabilization, power demand, and the like.

  Therefore, a method for producing hydrogen by electrolysis (electrolysis) of water using electric energy obtained from renewable energy, storing this hydrogen once, and generating electricity using this stored hydrogen as fuel when necessary is studied. ing.

  Among hydrogen production methods by electrolysis, high-efficiency techniques include high-temperature steam electrolysis using a solid oxide electrochemical cell. In general, steam electrolysis is performed using a solid oxide electrochemical cell group called a stack or a module, in which a plurality of cells are bundled and integrated.

JP 2010-232165 A

  The method for producing hydrogen by high-temperature steam electrolysis is a method for producing hydrogen by electrolyzing water vapor at a high temperature (mainly in a temperature range of 500 to 1000 ° C.) using a solid oxide electrochemical cell. In general, this solid oxide electrochemical cell is mainly disadvantageous in terms of strength as compared with metal materials and the like because it mainly comprises a solid oxide (ceramics). For this reason, it is required to prevent hydrogen and oxygen from diffusing into the surrounding environment from the solid oxide electrochemical cell or cell stack.

  The problem to be solved by the present invention is to provide a hydrogen leakage prevention system, a hydrogen leakage prevention method, a hydrogen production system, and an electric power storage system that improve safety by stopping the system immediately when hydrogen leaks. That is.

A hydrogen leakage prevention system according to an embodiment of the present invention includes:
An electrolysis unit that electrolyzes water vapor to produce hydrogen and oxygen;
An electric furnace that houses the electrolysis section in a furnace and heats the electrolysis section housed;
A supply pipe for supplying water vapor to the electrolysis unit;
An outflow pipe for flowing out hydrogen from the electrolysis section;
A detection device for detecting a gas component in the furnace of the electric furnace;
A determination device for determining the presence or absence of hydrogen leakage in the furnace from the data acquired from the detection device;
And a control device that controls the amount of water vapor supplied to the electrolysis unit based on the determination by the determination device.

  According to the embodiment of the present invention, when hydrogen leaks, safety can be improved by stopping the system immediately.

The conceptual diagram which shows the storage container by the 1st form of this invention. The conceptual diagram which shows a solid oxide form electrolysis cell. The conceptual diagram which shows the storage container by the 2nd form of this invention. The conceptual diagram which shows the storage container by the 3rd form of this invention. The conceptual diagram which shows the storage container by the 4th form of this invention. The conceptual diagram which shows the storage container by the 5th form of this invention. The conceptual diagram which shows the storage container by the 6th form of this invention. The conceptual diagram which shows the storage container by the 7th form of this invention. The conceptual diagram which shows the hydrogen production system and electric power storage system by embodiment of this invention.

<Hydrogen leakage prevention system>
<< First form >>
FIG. 1 shows an outline of a preferred specific example of a hydrogen leakage prevention system according to an embodiment of the present invention.
The hydrogen leakage prevention system shown in FIG.
An electrolysis unit 1 for electrolyzing water vapor to produce hydrogen and oxygen;
An electric furnace 2 that houses the electrolysis unit 1 in the furnace and heats the electrolysis unit 1 housed therein;
A supply pipe 3 for supplying water vapor to the electrolysis unit 1;
An outflow pipe 4 through which hydrogen flows out from the electrolysis unit 1;
A detection device 5 for detecting a gas component in the furnace of the electric furnace 2, and
A determination device 6 for determining the presence or absence of hydrogen leakage in the furnace from the data acquired from the detection device 5;
And a control device 7 for controlling the amount of water vapor supplied to the electrolysis unit based on the determination by the determination device 6.

The electrolysis unit 1 uses a solid oxide having ionic conductivity as an electrolyte, and a plurality of electrolysis cells formed by sandwiching the solid oxide electrolyte between a hydrogen electrode and an oxygen electrode. As shown in FIG. 2, one electrolytic cell 10 is configured by sandwiching an electrolyte 10a made of a solid oxide between a hydrogen electrode 10b and an oxygen electrode 10c, and water (H ₂ O) is placed on the hydrogen electrode 10b side. ) Is supplied in the form of water vapor, and hydrogen is generated by the reaction of H ₂ O + 2e ⁻ → H ₂ + O ²⁻ at the hydrogen electrode 10b, while O ²⁻ → 1/2 O ₂ + 2e ^{− at} the oxygen electrode 10c. As a result of the generation of oxygen by the reaction, water supplied to the electrolytic cell 10 is electrolyzed into hydrogen and oxygen.

  The electrolysis unit 1 can be formed by superposing a plurality of the electrolysis cells 10 (single cells). In addition, a separator (not shown) can be further arranged between individual cells as necessary.

  In the electric furnace 2, the electrolysis unit 1 is accommodated in the furnace, and a heater 9 is mainly disposed to heat the electrolysis unit 1 accommodated therein. The electric furnace 2 is preferably formed of a heat insulating material. One electric furnace 2 can accommodate one or a plurality of solid oxide electrolytic cell stacks 10.

  The electrolysis unit 1 includes a supply pipe 3 for supplying water vapor, an outflow pipe 4 for flowing out hydrogen generated in the electrolysis unit 1, and an oxygen outflow pipe for flowing out oxygen generated in the electrolysis unit 1 in some cases (see FIG. (Not shown) is connected. The electrolysis unit 1 is connected to a power supply line (not shown) for supplying power for electrolyzing water vapor.

  If there is leakage (for example, hydrogen, oxygen, or water vapor) from the electrolysis unit 1, these are inside the electric furnace 2 (that is, the inner surface 2 ′ of the electric furnace 2 and the electrolysis accommodated in the electric furnace 2. It leaks into the space 8) between the part 1. Here, a gas other than water vapor can be supplied to the electrolysis unit 1 together with water vapor as necessary. Examples of the gas other than water vapor include nitrogen and air.

  Hydrogen leaking into the gap 8 is detected by a hydrogen detection device 51 installed in the electric furnace 2, and the determination device 61 determines whether or not hydrogen leaks in the furnace from the data acquired from the detection device 51. Based on this, the controller 7 can control the amount of water vapor supplied to the electrolysis unit 1. For example, the hydrogen concentration in the electric furnace 2 is continuously or intermittently measured by the detection device 51, and the determination device 61 determines the presence of hydrogen in the gap 8 based on the measurement data of the detection device 51. When the presence of a small amount of hydrogen is determined (or when the presence of hydrogen of a predetermined concentration or more is determined), the supply of water vapor to the electrolysis unit 1 can be shut off by closing the control valve of the control device 7. Thereby, electrolysis of water vapor in the electrolysis unit 1 is stopped, generation of hydrogen is stopped, leakage of hydrogen into the electric furnace 2 is stopped, and an increase in hydrogen concentration can be suppressed.

  According to the hydrogen leakage prevention system according to the first aspect of the present invention, when hydrogen leaks from the electrolysis unit, safety can be improved by stopping the system immediately. And operation in the state where hydrogen production efficiency fell can be avoided.

<< Second form >>
FIG. 3 shows an outline of a preferable specific example of the hydrogen leakage prevention system according to the embodiment of the present invention.
The hydrogen leakage prevention system shown in FIG. 3 uses a “water vapor detection device 52” instead of the hydrogen detection device 51 shown in FIG. Therefore, except for the water vapor detection device 52, the same one as described above can be used for the first embodiment.

  In the second embodiment of the present invention, water vapor present in the furnace of the electric furnace 2 (that is, the gap 8) is detected by the water vapor detection device 52, and the data acquired from the detection device 52 is used in the electric furnace 2. The presence or absence of hydrogen leakage is determined by the determination device 62, and based on the determination, the amount of water vapor supplied to the electrolysis unit 1 is controlled by the control device 7.

  When water leaks from the electrolysis unit 1 to the gap 8, the water vapor detector 52 detects the leaked hydrogen, oxygen that is also present in the gap 8 (for example, oxygen in the air that is present in the gap 8), and the like. It is possible to detect water vapor which is a reaction product.

  The determination device 62 can determine the presence or absence of hydrogen leakage by comparing the data acquired from the water vapor detection device 52 with, for example, water vapor data stored in advance when there is no hydrogen leakage.

  When the determination device 62 determines the leakage of hydrogen, the control valve of the control device 7 can be closed to shut off the supply of water vapor to the electrolysis unit 1. Thereby, electrolysis of water vapor in the electrolysis unit 1 is stopped, generation of hydrogen is stopped, leakage of hydrogen into the electric furnace 2 is stopped, and an increase in hydrogen concentration can be suppressed.

  According to the hydrogen leakage prevention system according to the second aspect of the present invention described above, when hydrogen leaks from the electrolytic section, safety can be improved by stopping the system immediately. And operation in the state where hydrogen production efficiency fell can be avoided.

<< Third form >>
FIG. 4 shows an outline of a preferable specific example of the hydrogen leakage prevention system according to the embodiment of the present invention.
The hydrogen leakage prevention system shown in FIG. 4 is configured in such a manner that the detection device 51 is disposed in the flow path 11 of the gas component led from the inside of the electric furnace 2 (specifically, the gap 8). This is the same as the first embodiment shown in FIG.

  Therefore, the above-described one is provided with respect to the first embodiment except that a gas component flow path 11 is provided and the hydrogen detector 51 is installed so that the gas component guided from the furnace of the electric furnace 2 can be detected. Is the same.

  If the hydrogen detection device 51 can be installed there and the gas present in the gap 8 in the furnace of the electric furnace 2 can flow there, the structure 11 The form and the like are not particularly limited. For example, as shown in FIG. 4, the flow path 11 can have one end on the electric furnace 2 side opened to the gap 8 and the other end opened to the external space of the electric furnace 2. The flow path 11 may have an elongated tubular shape in which one end on the electric furnace 2 side is opened to the gap 8.

  The installation position of the gas component flow path 11 and the acquisition position of the gas from the electric furnace 2 are not particularly limited. Preferably, as shown in FIG. 4, the gas can be obtained from the inside of the electric furnace 3 through the opening 12 provided above the electric furnace 2 and provided in the ceiling of the electric furnace 2.

  The opening 12 can be provided with a gas flow rate adjusting mechanism 13 or the like as required. For example, when it is not necessary to detect the hydrogen concentration in the flow path 11, the gas flow is blocked by the gas flow rate adjusting mechanism 13, thereby preventing gas from leaking from the other opening of the flow path 11 to the outside. Can do. When the gas flow rate is lowered by the gas flow rate adjusting mechanism 13, the temperature drop in the electric furnace 2 accompanying the discharge of the high temperature gas can be suppressed. As the gas flow rate adjusting mechanism 13 in this case, a gas-permeable woven fabric, knitted fabric, cotton-like material, or the like can be preferably used.

  The determination device 61 determines whether or not hydrogen leaks in the furnace from the data installed in the flow path 11 and acquired from the water vapor detection device 51, and based on the determination, the control device 7 supplies water vapor to the electrolysis unit 1. The amount can be controlled.

  Thus, as in the first embodiment, the electrolysis of water vapor in the electrolysis unit 1 is stopped, the generation of hydrogen is stopped, the leakage of hydrogen into the electric furnace 2 is stopped, and the increase in the hydrogen concentration is suppressed. be able to.

  According to the hydrogen leakage prevention system according to the third aspect of the present invention described above, when hydrogen leaks from the electrolysis unit, safety can be improved by stopping the system immediately. And operation in the state where hydrogen production efficiency fell can be avoided.

  Further, by using the water vapor detection device 52 instead of the hydrogen detection device 51, the presence or absence of hydrogen leakage can be similarly determined. Based on the determination, the control device 7 controls the amount of water vapor supplied to the electrolysis unit 1. be able to.

<< Fourth form >>
FIG. 5 shows an outline of a preferable specific example of the hydrogen leakage prevention system according to the embodiment of the present invention.
The hydrogen leakage prevention system of the fourth form shown in FIG. 5 is the same as the third form shown in FIG. 4 except that the combustion catalyst 14 is installed. Therefore, except for the combustion catalyst 14, the third embodiment is the same as described above.

  The combustion catalyst 14 is not particularly limited in material and shape as long as it has an action of oxidizing hydrogen (the oxidation here includes combustion). As for the material, those containing noble metal components such as Pt and Ru are desirable. The shape may be particulate, cylindrical or honeycomb, but is not particularly limited.

  In the fourth embodiment, the combustion catalyst 14 is installed on the downstream side of the hydrogen detector 51 in the flow path of the gas component led from the furnace of the electric furnace 2 to the flow path 11. That is, the gas component guided from the gap 8 of the electric furnace 2 to the flow path 11 passes through the combustion catalyst 14 after the hydrogen concentration is measured by the hydrogen detector 51, and is then discharged from the flow path 11 to the outside. It has become so.

  Thus, even if hydrogen leaks from the electrolysis part 2 to the space | gap 8 by installing the combustion catalyst 14, it is prevented that the leaked hydrogen is discharged | emitted from the flow path 11 outside.

  Similarly to the third aspect, the determination device 61 determines whether or not hydrogen leaks in the furnace from the data installed in the flow path 11 and acquired from the hydrogen detection device 51, and on the basis of the determination device 61, The amount of water vapor supplied to the electrolysis unit 1 can be controlled.

  As a result, similarly to the third embodiment, the electrolysis of water vapor in the electrolysis unit 1 is stopped, the generation of hydrogen is stopped, the leakage of hydrogen into the electric furnace 2 is stopped, and the increase in the hydrogen concentration is suppressed. be able to.

  According to the hydrogen leakage prevention system according to the fourth embodiment of the present invention, when hydrogen leaks from the electrolysis unit, safety can be improved by quickly stopping the system. And operation in the state where hydrogen production efficiency fell can be avoided. Furthermore, since leakage of hydrogen from the electric furnace to the surrounding environment is prevented, further improvement in safety is achieved.

<< Fifth form >>
FIG. 6 shows an outline of a preferable specific example of the hydrogen leakage prevention system according to the embodiment of the present invention.
In the hydrogen leakage prevention system of the fifth embodiment shown in FIG. 6, specifically, the detection device 5 includes the combustion catalyst 14 and a device 15 for measuring the temperature of the combustion catalyst 14, and the determination device 63. However, based on the temperature data acquired from the device 15 for measuring the temperature of the combustion catalyst 14, the presence or absence of hydrogen leakage in the electric furnace 2 is determined. The amount of steam supplied can be controlled.

  The combustion catalyst 14 is not particularly limited in material and shape as long as it has an action of oxidizing hydrogen (the oxidation here includes combustion). As for the material, those containing noble metal components such as Pt and Ru are desirable. The shape may be particulate, cylindrical or honeycomb, but is not particularly limited.

  Since the temperature of the combustion catalyst 14 is increased due to the reaction between hydrogen and oxygen there, the temperature acquired from the “device (temperature sensor) 15 for measuring the temperature of the combustion catalyst 14” provided there. Based on the data, it is possible to detect the presence of hydrogen (that is, hydrogen leaked in the electric furnace 2) in the oxidation catalyst 14 and a change (for example, increase) in the amount of hydrogen.

  The determination device 63 determines whether or not hydrogen leaks in the electric furnace 2 from the data acquired from the device 15, and based on the determination, the control device 7 controls the amount of water vapor supplied to the electrolysis unit 1. it can.

  According to the hydrogen leakage prevention system according to the fifth aspect of the present invention described above, when hydrogen leaks from the electrolysis unit, safety can be improved by quickly stopping the system. And operation in the state where hydrogen production efficiency fell can be avoided. Furthermore, since leakage of hydrogen from the electric furnace to the surrounding environment is prevented, further improvement in safety is achieved.

<< Sixth form >>
FIG. 7 shows an outline of a preferable specific example of the hydrogen leakage prevention system according to the embodiment of the present invention.
In the hydrogen leakage prevention system of the sixth embodiment shown in FIG. 7, specifically, the detection device 5 has a device 16 for measuring a temperature change in the electric furnace 2, and the determination device 64 has the above-mentioned Determining whether or not hydrogen leaks in the electric furnace 2 from the temperature data acquired from the device 16 for measuring the temperature change, and based on that, the control device 7 controls the amount of steam supplied to the electrolysis unit 1 It is something that can be done.

  When the leakage of hydrogen occurs, the temperature in the electric furnace 2 rises due to the reaction between hydrogen and oxygen. Therefore, the “device 16 for measuring the temperature change in the electric furnace 2 provided there” is provided. The presence of hydrogen leaked in the electric furnace 2 and the change (for example, increase) in the amount of hydrogen present can be determined based on the temperature data acquired from “

  As the device 16 for measuring the temperature change, an electric resistor can be preferably used. This is to detect a temperature change from a change in resistance value by utilizing the fact that the resistance value of the electric resistor changes due to the temperature change.

  The determination device 64 determines the presence or absence of hydrogen leakage in the electric furnace 2 from the data acquired from the device 16, and the control unit 7 controls the amount of water vapor supplied to the electrolysis unit 1 based on the determination. it can.

  According to the hydrogen leakage prevention system according to the sixth aspect of the present invention, when hydrogen leaks from the electrolysis unit, safety can be improved by stopping the system immediately. And operation in the state where hydrogen production efficiency fell can be avoided. Furthermore, since leakage of hydrogen from the electric furnace to the surrounding environment is prevented, further improvement in safety is achieved.

<< Seventh form >>
FIG. 8 shows an outline of a preferable specific example of the hydrogen leakage prevention system according to the embodiment of the present invention.
Specifically, in the hydrogen leakage prevention system of the seventh embodiment shown in FIG. 8, the detection device 5 is a heater 9 disposed in the furnace of the electric furnace 2, and the control device is connected to the heater 9. The presence or absence of hydrogen leakage in the electric furnace 2 is determined from the obtained change in the electric resistance value of the heater 9, and based on this, the amount of water vapor supplied to the electrolysis unit 1 is controlled.

  A heater control device 17 that controls the output of the heater 9 can be connected to the heater 9. When the leakage of hydrogen occurs, the temperature in the electric furnace 2 rises due to the reaction between hydrogen and oxygen, and based on the decrease in the output of the heater 9 controlled by the heater controller 17, It is possible to detect the presence of hydrogen leaked in the electric furnace 2 and a change (for example, increase) in the amount of hydrogen present.

  Based on the data acquired from the heater 9, whether or not hydrogen leaks in the electric furnace 2 is determined by the determination device 65, and based on the determination, the control device 7 can control the amount of water vapor supplied to the electrolysis unit 1. .

  According to the hydrogen leakage prevention system according to the seventh aspect of the present invention, when hydrogen leaks from the electrolysis unit, safety can be improved by quickly stopping the system. And operation in the state where hydrogen production efficiency fell can be avoided. Furthermore, since leakage of hydrogen from the electric furnace to the surrounding environment is prevented, further improvement in safety is achieved.

<Hydrogen production system and power storage system>
FIG. 9 is a conceptual diagram of the hydrogen production system and the power storage system.
As shown in FIG. 9, the hydrogen production system uses a power generation unit (or electrical energy supply source) A and electric power generated by the power generation unit A to generate hydrogen by decomposing water into hydrogen and oxygen to produce hydrogen. And a decomposition part B. The power storage system includes a power generation unit (or electrical energy supply source) A, an electrolysis unit B that uses the power from the power generation unit A to decompose water into hydrogen and oxygen to produce hydrogen, and an electrolysis unit B. The storage part C which stores the hydrogen manufactured in (1), and the power generation part D which generates electric power using the stored hydrogen as a fuel are provided. In addition, the oxygen produced | generated in the electrolysis part B can be stored in the storage part E as needed, and this oxygen can also be utilized as a fluid-like combustion support substance.

  The hydrogen production system is a hydrogen production system for producing hydrogen by supplying water vapor and electric energy to the electrolysis unit B, and electrolyzing the water vapor in the electrolysis unit B, and includes a hydrogen leakage prevention system. It is done.

  The power storage system includes an electrolysis unit B that produces hydrogen by electrolysis of water vapor, a storage unit C that stores hydrogen, and a power generation unit D that generates power using the stored hydrogen as fuel. A system comprising a hydrogen leakage prevention system.

  Here, preferable specific examples of the hydrogen leakage prevention system include those described in the first to seventh embodiments, and these hydrogen leakage prevention systems are also shown in FIGS. Further, it can be adapted to the periphery of the electrolysis part B.

  In the hydrogen production system and the power storage system according to the embodiment of the present invention, when hydrogen leaks from the electrolysis unit, safety can be improved by stopping the system immediately. And operation in the state where hydrogen production efficiency fell can be avoided.

  As mentioned above, although some embodiment of this invention was described, these embodiment is shown as an example and is not intending limiting the range of invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the spirit of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

1: Electrolysis section, 2: Electric furnace, 3: Supply pipe, 4: Outflow pipe, 5: Detection device, 6: Determination device, 7: Control device, 8: Air gap, 9: Heater, 10: Solid oxide electrolyte cell 11: flow path, 12: opening, 13: gas flow rate adjusting mechanism, 14: combustion catalyst, 15: device for measuring temperature of combustion catalyst, 16: device for measuring temperature change, 17: heater control device, A: power generation unit, B: electrolysis unit, C: hydrogen storage unit, D: power generation unit, E: oxygen storage unit

Claims (9)

An electrolysis unit that electrolyzes water vapor to produce hydrogen and oxygen;
An electric furnace that houses the electrolysis section in a furnace and heats the electrolysis section housed;
A supply pipe for supplying water vapor to the electrolysis unit;
An outflow pipe for flowing out hydrogen from the electrolysis section;
A detection device for detecting a gas component in the furnace of the electric furnace;
A determination device for determining the presence or absence of hydrogen leakage in the furnace from the data acquired from the detection device;
A hydrogen leakage prevention system comprising: a control device that controls the amount of water vapor supplied to the electrolysis unit based on the determination by the determination device.   The hydrogen leakage prevention system according to claim 1, wherein the detection device detects at least one of a hydrogen gas component and a water vapor component in the furnace of the electric furnace.   The hydrogen leakage prevention system according to claim 1 or 2, wherein a gas component in the furnace of the electric furnace is processed by a combustion catalyst.   The hydrogen leakage prevention system according to claim 3, wherein the detection device includes a device that measures the temperature of the combustion catalyst.   The hydrogen leakage prevention system according to claim 1, wherein the detection device includes a device for measuring a temperature change in the furnace of the electric furnace.   The hydrogen leakage prevention system according to claim 1, wherein the detection device measures an output change of a heater disposed in the furnace of the electric furnace. An electrolysis unit that electrolyzes water vapor to produce hydrogen and oxygen;
An electric furnace that houses the electrolysis section in a furnace and heats the electrolysis section housed;
A supply pipe for supplying water vapor to the electrolysis unit;
An outflow pipe for flowing out hydrogen from the electrolysis section;
A detection device for detecting a gas component in the furnace of the electric furnace;
When performing hydrogen production by a hydrogen production apparatus comprising a control device for controlling the amount of water vapor supplied to the electrolysis unit,
A hydrogen leakage prevention method for determining whether or not hydrogen leaks in the furnace from data acquired from the detection device, and controlling an amount of water vapor supplied to the electrolysis unit based on the determination. A hydrogen production system for producing hydrogen by supplying water vapor and electric energy to an electrolysis unit, electrolyzing the water vapor in the electrolysis unit, and producing hydrogen,
A hydrogen production system comprising the hydrogen leakage prevention system according to any one of claims 1 to 6. An electric power storage system comprising an electrolysis unit that produces hydrogen by electrolysis of water vapor, a storage unit that stores the hydrogen, and a power generation unit that generates power using the stored hydrogen as a fuel,
A power storage system comprising the hydrogen leakage prevention system according to any one of claims 1 to 6.

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