WO2023132340A1

WO2023132340A1 - Hydrogen production device

Info

Publication number: WO2023132340A1
Application number: PCT/JP2023/000055
Authority: WO
Inventors: 甫戸田; 裕一阿部; 博文ジュニア和田
Original assignee: 京セラ株式会社
Priority date: 2022-01-06
Filing date: 2023-01-05
Publication date: 2023-07-13

Abstract

The hydrogen production device according to the present disclosure is provided with: a reducing agent; a container in which the reducing agent is stored; a water vapor generation unit for generating water vapor; a first flow path member for supplying the water vapor to the reducing agent; a heating furnace for generating a heated exhaust gas; a first heat exchanger for removing heat of the exhaust gas; a second flow path member for transferring the heat to the reducing agent by means of the heat-transferring fluid flowing in the interior; and a third flow path member for supplying the heat-transferring fluid to the first heat exchanger.

Description

Hydrogen production equipment

The disclosed embodiments relate to hydrogen production equipment.

For example, a technology has been proposed in which hydrogen is generated by reducing a catalyst using heat emitted from an industrial furnace such as a blast furnace, and oxidizing the catalyst by contacting water vapor with the reduced catalyst (for example, , see Patent Document 1).

WO2013/141385

A hydrogen production apparatus according to an aspect of an embodiment includes a reducing agent, a container that stores the reducing agent, a steam generating unit that generates steam, a first channel member that supplies the steam to the reducing agent, A heating furnace for generating heated exhaust gas, a first heat exchanger for extracting heat from the exhaust gas, a second channel member for transferring the heat to the reducing agent, and a heat transfer channel for circulating the heat transfer channel. A heat transfer fluid and a third flow path member supplying the heat transfer fluid to the first heat exchanger.

FIG. 1 is a diagram schematically showing the configuration of the hydrogen production apparatus of the present disclosure. FIG. 2 is a diagram showing another example of the hydrogen production device of the present disclosure. FIG. 3 is a diagram showing another example of the hydrogen production device of the present disclosure. FIG. 4 is a diagram showing another example of the hydrogen production device of the present disclosure. FIG. 5 is a diagram showing another example of the hydrogen production device of the present disclosure. FIG. 6 is a diagram showing another example of the hydrogen production device of the present disclosure. FIG. 7 is a diagram showing another example of the hydrogen production device of the present disclosure.

Hereinafter, each embodiment of the hydrogen production apparatus disclosed in the present application will be described with reference to the accompanying drawings. In addition, this disclosure is not limited by each embodiment shown below. Also, it should be noted that the drawings are schematic, and the relationship of dimensions of each element, the ratio of each element, and the like may differ from reality. Furthermore, even between the drawings, there are cases where portions having different dimensional relationships and ratios are included.

For example, Patent Document 1 proposes a technology for generating hydrogen by reducing a catalyst using heat emitted from an industrial furnace such as a blast furnace, and oxidizing the catalyst by contacting water vapor with the reduced catalyst. It is In addition, although it is described as a catalyst in Patent Document 1, it is expressed as a reducing agent in the present application. Fundamentally, the reducing agent of the present application can be considered the same as the catalyst described in the prior art. In this application, the description of the catalyst may be used in the description of the prior art.

In the above conventional technology, there was a point to be improved in the efficiency of transferring heat from the blast furnace, etc. to the catalyst. Therefore, the conventional technology described above has room for improvement in terms of efficiently producing hydrogen.

Therefore, the realization of a technology that can overcome the above-mentioned problems and improve the efficiency of hydrogen generation is expected.

FIG. 1 is a diagram schematically showing the configuration of the hydrogen production device 1 of the present disclosure. The hydrogen production apparatus 1 includes a reducing agent 10, a container 11 containing the reducing agent 10, a steam generating section 12, a first flow path member 13, a heating furnace 14, a first heat exchanger 15, a second It has a channel member 16 , a heat transfer fluid 17 and a third channel member 18 .

The reducing agent 10 has the function of coming into contact with water vapor, depriving the water vapor of oxygen, and reducing the water vapor to generate hydrogen. A container 11 contains a reducing agent 10 used to produce hydrogen. The reducing agent 10 may have a central channel through which various fluids can pass. Alternatively, the reducing agent 10 may be a cylindrical porous body into which a tubular structure can be inserted. The reducing agent 10 may be, for example, an oxide that is thermally reduced to create oxygen vacancies. As the reducing agent 10, for example, a perovskite oxide can be used. With the perovskite oxide described in Patent Document 1, the hydrogen production cycle can be performed in the temperature range of 400° C. or higher and 1600° C. or lower. A reducing agent 10 is contained in a container 11 .

The steam generator 12 has a function of heating water, which is a raw material, to generate steam. The first channel member 13 is a channel for supplying the reducing agent 10 with the steam generated by the steam generator 12 . In other words, the steam generating part 12 and the container 11 containing the reducing agent 10 may be connected. The steam becomes superheated steam when it is supplied to the reducing agent 10 . The steam generator 12 may generate superheated steam, or a device may be used to heat the steam generated by the steam generator 12 to obtain superheated steam. The notation of steam in the specification of the present application may be read as superheated steam.

The heating furnace 14 is a variety of furnaces that are used in various industries and have high internal temperatures. The heating furnace 14 generates an exhaust gas 14a. The heating furnace 14 may be, for example, a firing furnace, a heat treatment furnace, a power plant, a waste incinerator, a blast furnace, an electric furnace, an industrial gas synthesizing device, a gasification device, a cement clinker firing furnace, or the like.

The first heat exchanger 15 has a function of extracting heat from the exhaust gas 14a. The heat of the exhaust gas 14 a is transferred to the heat transfer fluid 17 flowing through the second flow path member 16 . A heat transfer fluid 17 is supplied to the first heat exchanger 15 by a third channel member 18 .

A hydrogen production device with such a configuration can efficiently produce hydrogen. That is, the flow rate and temperature of the heat transfer fluid 17 sent to the third flow path member 18 can be freely changed according to the flow rate and temperature of the exhaust gas 14a, so that the efficiency of hydrogen production can be improved.

The container 11 may be connected to a gas recovery unit 24 that recovers hydrogen obtained by bringing water vapor into contact with the reducing agent 10 . The gas recovery unit 24 may include, for example, a hydrogen separation membrane or a hydrogen storage alloy (not shown). Also, the gas recovery unit 24 may have other means for separating hydrogen from other gases, water vapor, and the like. Further, the gas recovery section 24 may be equipped with, for example, a vacuum suction machine to suck the gas from the container 11 .

Heat transfer fluid 17 may be a non-oxidizing gas. Using a substantially oxygen-free heat transfer fluid 17 allows the heat transfer fluid 17 to contact the reducing agent 10 to effectively reduce the reducing agent 10 . The heat transfer fluid 17 may contain at least one of Ar gas, _N2 gas and _CO2 gas. These gases are readily available. In particular, it is preferable that the sum of Ar gas, N ₂ gas and CO ₂ gas occupies 70% by volume or more of the heat transfer fluid 17 .

The heat transfer fluid 17 may be a metal with a melting point of 300°C or less. The heat transfer fluid 17 may be a metal with a boiling point of 700° C. or higher. Specifically, the heat transfer fluid 17 may be sodium, potassium. Alternatively, the heat transfer fluid 17 may be a metal with a melting point of 600° C. or less. Heat transfer fluid 17 may be a metal with a boiling point of 1200° C. or higher. Specifically, the heat transfer fluid 17 may contain at least one of lithium, indium and gallium.

The hydrogen production apparatus 1 of the present disclosure may also have a fourth flow path member 19 that connects with the second flow path member 16 and supplies the heat transfer fluid 17 to the first heat exchanger 15 . The hydrogen production apparatus 1 having such a configuration reduces heat loss by supplying the once heated heat transfer fluid 17 to the first heat exchanger 15 again.

In addition, as shown in FIG. 2 , in the hydrogen production apparatus 1 of the present disclosure, the second flow path member 16 may be connected to a fifth flow path member 20 that supplies the cooling fluid 20 a to the reducing agent 10 . A hydrogen production apparatus having such a configuration can shorten the time for cooling the reducing agent 10 and has high efficiency in hydrogen production.

Further, as shown in FIG. 3 , in the disclosed hydrogen production apparatus 1 , the fifth channel member 20 may be connected to the third channel member 18 . The hydrogen production apparatus 1 having such a configuration can flow the cooling fluid 20a for cooling the reducing agent 10 using the third flow path member 18. Therefore, the structure of the hydrogen production apparatus 1 is can be simplified.

Also, the cooling fluid 20a made of the same material as the heat transfer fluid 17 may be used. In other words, the cooling fluid may be of the same material as the heat transfer fluid. Since the hydrogen production apparatus 1 having such a configuration can use the heat transfer fluid 17 as the cooling fluid 20a, the structure of the hydrogen production apparatus 1 can be simplified.

As shown in FIG. 4 , in the hydrogen production device 1 of the present disclosure, the second channel member 16 may also serve as the first channel member 13 . The hydrogen production device 1 having such a configuration can simplify the structure of the hydrogen production device 1 . In such a case, gas may be used as the heat transfer fluid 17 . A heat transfer fluid 17 containing water vapor V can then be contacted with the reducing agent 10 to produce hydrogen.

In addition, in the hydrogen production apparatus 1 of the present disclosure, the third channel member 18 may also serve as the first channel member 13 . Since the hydrogen production device 1 having such a configuration can supply the steam V to the first heat exchanger 15, the steam V can be heated and the structure of the hydrogen production device 1 can be simplified. .

When the heat transfer fluid 17 or superheated steam is ejected from the second channel member 16 to directly contact the reducing agent 10 , a plurality of A hole should be provided.

Further, as shown in FIG. 5 , in the hydrogen production apparatus 1 of the present disclosure, even if the steam generating section 12 has the second heat exchanger 21 that generates steam using the heat of the heat transfer fluid 17, good. The hydrogen production apparatus 1 having such a configuration can save energy for generating steam using the water 12a, and thus has high efficiency.

In addition, as shown in FIG. 6, in the hydrogen production device 1 of the present disclosure, the water vapor generating section 12 may include a third heat exchanger 23 that generates water vapor using the heat of the exhaust gas 14a. . The hydrogen production apparatus 1 having such a configuration can save energy for generating steam, and thus has high efficiency.

In addition, as shown in FIG. 7, the second flow path member 16 of the hydrogen production apparatus 1 of the present disclosure may have a first heating section 26 that heats at least one of the heat transfer fluid 17 and water vapor. . The hydrogen production apparatus 1 having such a configuration can supply the heat transfer fluid 17 and steam heated by the first heating unit 26 to the reducing agent 10 in the container 11, and thus has high efficiency.

Further, the hydrogen production device 1 of the present disclosure may have a second heating unit 27 that heats the reducing agent 10 . Since the hydrogen production apparatus 1 having such a configuration can stably heat the reducing agent 10 by the second heating unit 27, the efficiency is high.

The reducing agent 10 may be provided with various measuring instruments for managing the reaction state of the reducing agent 10 . As the measuring instrument, for example, a displacement meter, a weight meter, an electrometer, or the like can be used. These measuring instruments may be used in combination as appropriate.

The displacement meter can measure the expansion and contraction of the reducing agent 10 as an indicator of the reaction state of the reducing agent 10 . The weight scale can measure an increase or decrease in weight of the reducing agent 10 . An electrometer can measure changes in potential of a conductive element attached to the reducing agent 10 .

As the conductive element, for example, ceramics having oxygen defects such as titanium oxide or rare earth-stabilized zirconium oxide can be used. When using ceramics with oxygen vacancies, an electrometer can measure the potential because the amount of oxygen vacancies changes due to oxidation-reduction reactions, similar to perovskite-type oxides, and the oxygen ion conductivity changes accordingly. . In the case of such a conductive element, since it is the same ceramic as the perovskite oxide, it has substantially the same coefficient of thermal expansion, and cracks due to the difference in coefficient of thermal expansion during temperature cycles are less likely to occur. Further, the reducing agent 10 may be provided with a temperature sensor capable of detecting the temperature of the reducing agent 10 . Moreover, the shape of the reducing agent 10 is not limited to a cylindrical shape, and may be, for example, a rectangular cylindrical shape.

The heat transfer fluid 17 transports the heat H generated in the heating furnace 14 into the container 11, and the heat H reduces the reducing agent 10. Reduction of the reducing agent 10 is achieved, for example, by heating the reducing agent 10 to a temperature of about 800° C. with heat H transported from the heating furnace 14 .

The second flow path member 16 is, for example, a hollow member whose both ends are attached to the first heat exchanger 15, the container 11, and the reducing agent 10, respectively. Alternatively, the second channel member 16 may be a hollow member having the container 11 and the reducing agent 10 attached between both ends thereof.

When the heat transfer fluid 17 is a liquid metal, the material of the tubular body used for the second flow path member 16 includes, for example, highly corrosion-resistant materials such as inconel, beryllia, and boron nitride. When the heat transfer fluid 17 of the second channel member 16 is Ar gas, N ₂ gas, or CO ₂ gas, the material of the tubular body used for the second channel member 16 includes, for example, ceramics and stainless steel. etc.

Also, the first heat exchanger, the second heat exchanger, the third heat exchanger, and the container may partially have stainless steel, Inconel, or ceramic. With such a structure, heat resistance is high, so reliability can be improved. In particular, ceramics such as alumina, silicon carbide, silicon nitride, and aluminum nitride are preferable. In addition, the heat exchanger may be arranged by penetrating into each channel member.

Also, the first heating unit and the second heating unit may have heating elements. As the heating element, a nichrome wire, a kanthal wire, a ceramic heater, or the like is preferable, and these heating elements are arranged so as to be in contact with the second channel member or the reducing agent, or are arranged so as to penetrate the second channel member or the reducing agent. You can As the ceramic heater, it is preferable to have a resistor layer mainly composed of tungsten, molybdenum, tantalum, carbides thereof, or titanium nitride, and to use silicon nitride or alumina as the base material.

In addition, it is desirable that the hydrogen production device 1 be covered with a heat insulating material. With such a structure, the thermal efficiency of the hydrogen production device 1 is improved, and hydrogen production can be efficiently performed. The heat insulating material may be brick, glass wool, ceramic fiber, rock wool, alumina-silica mat, or the like, and an inorganic adhesive or the like may be used for bonding.

Also, a heat insulating material may be provided between the reducing agent 10 and the container 11 . With such a structure, the heat of the reducing agent 10 is less transmitted to the container 11, so that the efficiency is good and the deterioration of the container 11 due to heat can be prevented.

The steam generator 12 supplies steam V to the reducing agent 10 in the container 11 . The steam V contacts the reduced reducing agent 10, the oxygen of the steam combines with the reducing agent 10, and the hydrogen of the steam becomes hydrogen gas. That is, when the reduced reducing agent 10 and the water vapor V come into contact with each other, oxygen contained in the water vapor V is taken into the oxygen vacancies of the reducing agent 10 and hydrogen gas is generated. Such steam V may be superheated steam. Superheated steam makes it difficult to lower the temperature of the reducing agent 10 .

The generation of hydrogen is realized, for example, by lowering the temperature of the reduced reducing agent 10 to 400° C. to 800° C. and then bringing the reducing agent 10 into contact with water vapor V.

A raw water supply source (not shown) and a water supply pipe (not shown) may be connected to the steam generator 12 .

The raw water supply source is, for example, a tank that stores the raw water W that is the raw material of the steam V. Note that the raw water W stored in the raw water supply source may be water that is removed when hydrogen is recovered in the gas recovery unit 24 .

The gas recovery unit 24 may have a plurality of recovery units for recovering the gas generated inside the container 11 and the gas remaining inside the container 11 .

For example, the gas recovery unit 24 includes a recovery unit (not shown) that recovers hydrogen generated in the container 11 and a recovery unit (not shown) that recovers oxygen generated when reducing the reducing agent 10 in the container 11. ) and a recovery unit (not shown) for recovering the atmosphere such as moisture remaining in the container 11 .

Various sensors for detecting the amount of gas generated in the container 11 and the like may be provided in the container 11, the gas recovery unit 24, and the recovery unit. As the sensor, for example, an infrared flow sensor, a differential thermal flow sensor, a partial pressure sensor, or the like can be used.

It should be noted that the hydrogen production device 1 of the present disclosure may be provided with a valve 25 . The hydrogen production apparatus 1 having such a configuration facilitates control when the heat transfer fluid 17 and the steam V flow. As the valve 25, for example, a valve 25a may be provided at the connecting portion between the second channel member 16 and the fourth channel member 19. FIG. Also, a valve 25 b may be provided at the connecting portion between the second channel member 16 and the fifth channel member 20 . Also, a valve 25 c may be provided at the connecting portion of the first flow path member 13 (or the third flow path member 18 ), the fourth flow path member 19 and the fifth flow path member 20 .

The hydrogen production device 1 may further have a control unit (not shown). Such a control unit may be, for example, a computer including a processor, a storage unit, an input device, a display device, and the like. The storage unit of the control unit may store a control program for controlling various processes executed by the hydrogen production device 1 by the processor. The processor of the control unit may operate based on the control program stored in the storage unit to control the operation of the hydrogen production device 1 as a whole.

A method for producing hydrogen using the hydrogen production apparatus 1 of the present disclosure will be described below.

First, an explanation will be given using the example in FIG. First, the reducing agent is heated to a first temperature to reduce the reducing agent. In other words, heating deprives the reducing agent of oxygen. In other words, oxygen is released from the reducing agent to create oxygen vacancies in the reducing agent. To heat the reductant, the heat transfer fluid heated by the first heat exchanger may be supplied to the reductant through the second flow path member. After reducing the reducing agent, the temperature of the reducing agent is lowered to a second temperature that is lower than the first temperature. Next, by supplying steam to the reducing agent at the second temperature, hydrogen can be produced from the steam.

It should be noted that, during the reduction treatment of the reducing agent, the supply of the cooling fluid to the reducing agent should be cut off in the hydrogen production apparatus having the fifth channel member.

By producing hydrogen, the reducing agent is oxidized, so the hydrogen production capacity decreases. Therefore, next, the supply of steam to the reducing agent 10 is stopped.

Next, return to the step of heating the reducing agent to reduce the reducing agent. By repeating the steps of hydrogen production involving reduction of the reducing agent and oxidation of the reducing agent in this manner, highly efficient hydrogen production using the hydrogen production apparatus 1 of the present disclosure can be realized.

Although the embodiments of the present disclosure have been described above, the present disclosure is not limited to the above embodiments, and various modifications are possible without departing from the spirit of the present disclosure.

Each embodiment disclosed this time should be considered as an example and not restrictive in all respects. Indeed, each of the above-described embodiments can be embodied in various forms. Moreover, each of the above-described embodiments may be omitted, substituted, or modified in various ways without departing from the scope and spirit of the appended claims.

In addition, regarding the above embodiment, the following additional remarks are disclosed.

(Appendix 1)
a reducing agent;
a container containing the reducing agent;
a steam generator that generates steam;
a first channel member for supplying the water vapor to the reducing agent; a heating furnace for generating heated exhaust gas;
a first heat exchanger that extracts heat from the exhaust gas;
a second channel member that transfers the heat to the reducing agent by means of a heat transfer fluid flowing therein;
a third channel member for supplying the heat transfer fluid to the first heat exchanger;
A hydrogen production device.

(Appendix 2)
2. The hydrogen production apparatus of claim 1, wherein the heat transfer fluid is a non-oxidizing gas.

(Appendix 3)
3. The hydrogen production apparatus according to appendix 2, wherein the heat transfer fluid contains at least one of Ar gas, _N2 gas, and _CO2 gas.

(Appendix 4)
4. The hydrogen production apparatus according to any one of Appendices 1 to 3, wherein the heat transfer fluid is a metal having a melting point of 300° C. or lower and a boiling point of 700° C. or higher.

(Appendix 5)
5. The hydrogen generator according to appendix 4, wherein the heat transfer fluid contains at least one of sodium, potassium, lithium, indium and gallium.

(Appendix 6)
6. The hydrogen production apparatus according to any one of Appendices 1 to 5, further comprising a fourth flow path member connected to the second flow path member and supplying the heat transfer fluid to the first heat exchanger.

(Appendix 7)
7. The hydrogen production apparatus according to any one of appendices 1 to 6, wherein the second flow path member is connected to a fifth flow path member that supplies a cooling fluid to the reducing agent.

(Appendix 8)
The hydrogen production apparatus according to appendix 7, wherein the fifth flow path member is connected to the third flow path member.

(Appendix 9)
9. The hydrogen production apparatus according to appendix 7 or 8, wherein the cooling fluid is made of the same material as the heat transfer fluid.

(Appendix 10)
10. The hydrogen production device according to any one of Appendixes 1 to 9, wherein the second channel member also serves as the first channel member.

(Appendix 11)
11. The hydrogen production apparatus according to any one of Appendices 1 to 10, wherein the steam generating unit has a second heat exchanger that uses the heat of the heat transfer fluid to generate steam.

(Appendix 12)
12. The hydrogen production apparatus according to any one of Additions 1 to 11, wherein the steam generating unit has a third heat exchanger that uses the heat of the exhaust gas to generate steam.

(Appendix 13)
13. The hydrogen production apparatus according to any one of Additions 1 to 12, wherein the second flow path member has a first heating section that heats at least one of the heat transfer fluid and the steam.

(Appendix 14)
14. The hydrogen production device according to any one of Additions 1 to 13, wherein the container has a second heating unit that heats the reducing agent.

REFERENCE SIGNS LIST 1 hydrogen production device 10 reducing agent 11 container 12 steam generator 13 first channel member 14 heating furnace 14a exhaust gas 15 first heat exchanger 16 second channel member 17 heat transfer fluid 18 third channel member 19 fourth fourth channel member Flow path member 20 Fifth flow path member 20a Cooling fluid 21 Second heat exchanger 23 Third heat exchanger 24

Gas recovery section

25a, 25b, 25c Valve 26 First heating section 27 Second heating section

Claims

a reducing agent;
a container containing the reducing agent;
a steam generator that generates steam;
a first channel member for supplying the water vapor to the reducing agent; a heating furnace for generating heated exhaust gas;
a first heat exchanger that extracts heat from the exhaust gas;
a second channel member that transfers the heat to the reducing agent by means of a heat transfer fluid flowing therein;
a third channel member for supplying the heat transfer fluid to the first heat exchanger;
A hydrogen production device.
The hydrogen production apparatus according to claim 1, wherein the heat transfer fluid is a non-oxidizing gas.
3. The hydrogen generator according to claim 2, wherein the heat transfer fluid contains at least one of Ar gas, N2 gas, and CO2 gas.
The hydrogen production apparatus according to claim 1, wherein the heat transfer fluid is a metal with a melting point of 300°C or lower and a boiling point of 700°C or higher.
The hydrogen production apparatus according to claim 4, wherein the heat transfer fluid contains at least one of sodium, potassium, lithium, indium and gallium.
2. The hydrogen production apparatus according to claim 1, further comprising a fourth flow path member connected to said second flow path member and supplying said heat transfer fluid to said first heat exchanger.
The hydrogen production apparatus according to claim 1, wherein the second channel member is connected to a fifth channel member that supplies a cooling fluid to the reducing agent.
The hydrogen production apparatus according to claim 7, wherein the fifth channel member is connected to the third channel member.
The hydrogen production apparatus according to claim 7, wherein the cooling fluid is made of the same material as the heat transfer fluid.
The hydrogen production apparatus according to claim 1, wherein the second channel member also serves as the first channel member.
The hydrogen production apparatus according to claim 1, wherein the steam generating section has a second heat exchanger that generates steam using the heat of the heat transfer fluid.
The hydrogen production apparatus according to claim 1, wherein the steam generating unit has a third heat exchanger that generates steam using the heat of the exhaust gas.
The hydrogen production apparatus according to claim 1, wherein the second flow path member has a first heating section that heats at least one of the heat transfer fluid and the steam.
The hydrogen production apparatus according to claim 1, wherein the container has a second heating unit that heats the reducing agent.