Hydrogen generation system and control method for hydrogen generation system
Patent Information
- Application Number
- CN202480086463.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Priority Date
- 2024-01-31
- Filing Date
- 2024-11-29
- Publication Date
- 2026-08-28
AI Technical Summary
[0014] According to this disclosure, a hydrogen generation system and a control method for the hydrogen generation system can be provided that can appropriately raise the temperature of the electrolysis module to shorten the start-up time even when the heat generated by the combustion of fuel gas caused by the catalytic action of the oxygen electrode is insufficient.
Smart Images
Figure CN122663333A_ABST
Abstract
Description
Technical Field
[0001] This disclosure relates to hydrogen generation systems and control methods for hydrogen generation systems. Background Technology
[0002] Previously, hydrogen generation systems that produce hydrogen through steam electrolysis were known (for example, see Patent Document 1). The hydrogen generation system disclosed in Patent Document 1 includes an electrolysis module having a solid oxide electrolytic cell (SOEC). Patent Document 1 discloses that hydrogen is supplied not only to the hydrogen electrode of the electrolysis module but also to the oxygen electrode, thereby causing the hydrogen to burn using a catalytic reaction at the oxygen electrode, thus raising the temperature of the electrolysis module.
[0003] Existing technical documents
[0004] Patent documents
[0005] Patent Document 1: Japanese Patent No. 7282968 Summary of the Invention
[0006] The problem that the invention aims to solve
[0007] However, if the temperature of the hydrogen supplied to the oxygen electrode exceeds the ignition temperature and spontaneously combusts, the electrolysis module may be damaged. Reducing the concentration of hydrogen supplied to the oxygen electrode can prevent spontaneous combustion, but it also reduces the heat generated by the combustion of hydrogen due to the catalytic action of the oxygen electrode. Therefore, the rate of temperature rise in the electrolysis module decreases, and the start-up time of the hydrogen generation system becomes longer.
[0008] This disclosure was made in view of the following circumstances, and its purpose is to provide a hydrogen generation system and a method for controlling the hydrogen generation system that can appropriately raise the temperature of the electrolysis module to shorten the start-up time even when the heat generated by the combustion of fuel gas caused by the catalytic action of the oxygen electrode is insufficient.
[0009] Methods for solving problems
[0010] To address the aforementioned issues, the present disclosure employs the following methods.
[0011] The hydrogen generation system disclosed herein comprises: an electrolysis module having an electrolytic cell having a hydrogen electrode, an oxygen electrode, and an electrolyte layer disposed between the hydrogen electrode and the oxygen electrode, the electrolysis module supplying water vapor to the hydrogen electrode and generating hydrogen by electrolysis of the water vapor; a water vapor supply unit supplying the water vapor to the hydrogen electrode; an air supply unit supplying air to the oxygen electrode; a fuel gas system supplying fuel gas to the oxygen electrode; a power supply unit supplying power to the electrolysis module; and a control unit controlling the hydrogen generation system, wherein the control unit controls the power supply unit to start supplying power to the electrolysis module in response to the temperature of the electrolysis module exceeding a first predetermined temperature lower than the ignition temperature of the fuel gas.
[0012] In the control method of the hydrogen generation system disclosed herein, the hydrogen generation system comprises: an electrolysis module having an electrolytic cell having a hydrogen electrode, an oxygen electrode, and an electrolyte layer disposed between the hydrogen electrode and the oxygen electrode, the electrolysis module supplying water vapor to the hydrogen electrode and generating hydrogen by electrolysis of the water vapor; a water vapor supply unit supplying the water vapor to the hydrogen electrode; an air supply unit supplying air to the oxygen electrode; a fuel gas system supplying fuel gas to the oxygen electrode; and a power supply unit supplying power to the electrolysis module. The control method of the hydrogen generation system includes a control step in which the power supply unit is controlled to start supplying power to the electrolysis module in response to the temperature of the electrolysis module exceeding a first predetermined temperature lower than the ignition temperature of the fuel gas.
[0013] Invention Effects
[0014] According to this disclosure, a hydrogen generation system and a control method for the hydrogen generation system can be provided that can appropriately raise the temperature of the electrolysis module to shorten the start-up time even when the heat generated by the combustion of fuel gas caused by the catalytic action of the oxygen electrode is insufficient. Attached Figure Description
[0015] Figure 1 This is a diagram showing the outline structure of a hydrogen generation system according to one embodiment of the present disclosure.
[0016] Figure 2 This is a partial cross-sectional view showing an example of a cylindrical electrolysis module according to one embodiment of the present disclosure.
[0017] Figure 3 yes Figure 1 The image shows a longitudinal sectional view of the electrolysis module.
[0018] Figure 4 This is a flowchart illustrating the actions of the hydrogen generation system during startup.
[0019] Figure 5 This is a flowchart illustrating the actions of the hydrogen generation system during startup. Detailed Implementation
[0020] The following is for reference Figure 1 An embodiment of the hydrogen generation system 100 of this disclosure will be described. Figure 1 This is a diagram showing the schematic structure of a hydrogen generation system 100 according to one embodiment of this disclosure. (See diagram for details.) Figure 1 As shown, the hydrogen generation system 100 of this embodiment includes an electrolysis module 19, an electric power supply unit 18, a steam supply unit 20, a hydrogen separation device 30, a hydrogen storage device (hydrogen supply unit) 40, an adjustment unit 50, an air supply unit (heating medium supply unit) 70, and a control device (control unit) 80.
[0021] It should be noted that this disclosure shows a system equipped with a hydrogen storage device (hydrogen supply unit), but the hydrogen storage device (hydrogen supply unit) 40 can be a hydrogen pipeline, or hydrogen can be drawn from a pipeline and supplied to this system, and the generated hydrogen can be directly supplied to the hydrogen pipeline.
[0022] A solid oxide electrolytic cell (hereinafter referred to as an electrolytic cell) 10 is an element constituting an electrolysis module 19. The electrolysis module 19 supplies water vapor from a steam supply unit 20 to a hydrogen electrode 11 and generates hydrogen and oxygen through steam electrolysis. The solid oxide electrolytic cell 10 has a hydrogen electrode 11, an oxygen electrode 12, and an electrolyte layer 13 disposed between the hydrogen electrode 11 and the oxygen electrode 12. The electrolysis module 19 is an assembly of the electrolytic cells 10. Steam electrolysis is the reverse reaction of a fuel cell that generates electricity. The electrolysis cell 10 can use substantially the same structure and materials as a solid oxide fuel cell unit (SOFC).
[0023] exist Figure 1 The diagram schematically illustrates the relationship between the electrolysis module 19, the hydrogen electrode 11, the oxygen electrode 12, and the electrolyte layer 13. For example, the electrolysis module 19 can be a cylindrical battery stack in which the hydrogen electrode 11 is disposed on a tube made of a porous material, the electrolyte layer 13 is disposed on the hydrogen electrode 11, and the oxygen electrode 12 is disposed on the electrolyte layer 13. Furthermore, the electrolysis module 19 includes a temperature sensor 17 for measuring the operating temperature.
[0024] Figure 2 This is a partial cross-sectional view showing an example of a cylindrical battery stack CS according to this embodiment. As an example, the battery stack CS includes a cylindrical base tube 14, multiple electrolytic cells 10 formed at various locations on the outer peripheral surface of the base tube 14, and interconnectors 15 formed between adjacent electrolytic cells 10. The electrolytic cells 10 are formed by stacking a hydrogen electrode 11, an electrolyte layer 13, and an oxygen electrode 12 on the surface of the base tube 14.
[0025] The battery stack CS is equipped with a lead film 16 electrically connected to the oxygen electrode 12 of one of the multiple electrolytic cells 10 formed on the outer peripheral surface of the base tube 14 via an interconnector 15, and also equipped with a lead film 16 electrically connected to the hydrogen electrode 11 of the electrolytic cell 10 formed on the other end of the base tube 14. It should be noted that, in the following description, "supplying a medium (air, water vapor, hydrogen, etc.) to the hydrogen electrode 11" means supplying the medium to the hydrogen electrode 11 formed on the outer peripheral surface of the base tube 14 by allowing the medium to circulate in the space inside the base tube 14 of the battery stack CS, thereby diffusing the medium through the fine pores of the base tube 14.
[0026] The substrate tube 14 is made of a porous material, such as CaO-stabilized ZrO2 (CSZ), a mixture of CSZ and nickel oxide (NiO) (CSZ+NiO), Y2O3-stabilized ZrO2 (YSZ), or MgAl2O4 as the main components. The substrate tube 14 supports the electrolytic cell 10, the interconnect 15, and the lead film 16, and allows water vapor supplied to the inner peripheral surface of the substrate tube 14 to diffuse through the fine pores of the substrate tube 14 to the hydrogen electrode 11 formed on the outer peripheral surface of the substrate tube 14.
[0027] The hydrogen electrode 11 is composed of an oxide composite material of a metallic material (e.g., Ni) and a zirconium oxide-based electrolyte material, such as Ni / YSZ. The oxygen electrode 12 is composed of, for example, LaSrMnO3-based oxides or LaCoO3-based oxides. As the electrolyte layer 13, YSZ, which has gas tightness that makes it difficult for gases to pass through and high oxygen ion conductivity at high temperatures, is mainly used.
[0028] Interconnector 15, for example, is made of SrTiO3 system, etc., using M 1-x L x It is composed of a conductive perovskite-type oxide, represented by TiO3 (M being an alkaline earth metal element and L being a lanthanide element). The interconnect 15 is a dense film to prevent water vapor from mixing with air (oxidizing gas).
[0029] Furthermore, the interconnect 15 exhibits stable durability and conductivity in both oxidizing and reducing atmospheres. The interconnect 15 electrically connects the oxygen electrode 12 of one electrolytic cell 10 to the hydrogen electrode 11 of another electrolytic cell 10 in adjacent electrolytic cells 10, thus connecting adjacent electrolytic cells 10 in series.
[0030] The lead film 16 is electronically conductive and is composed of a composite material of Ni / YSZ and zirconium oxide electrolyte, or SrTiO3-xLxTiO3 (where M is an alkaline earth metal and L is a lanthanide element). The lead film 16 supplies DC power to multiple electrolytic cells 10 connected in series via interconnect 15.
[0031] When electricity is supplied from the outside to the hydrogen electrode 11 and the oxygen electrode 12 via the lead membrane 16, a portion of the high-temperature water vapor supplied to the hydrogen electrode 11 accepts electrons and separates into hydrogen and oxygen ions, generating hydrogen. The separated oxygen ions move towards the oxygen electrode 12 inside the electrolyte layer 13, releasing electrons to generate oxygen.
[0032] Temperature sensor 17 is a sensor that detects the temperature of electrolysis module 19 (the temperature of electrolytic cell 10 itself, or the ambient temperature of the space where electrolytic cell 10 is disposed). The temperature of electrolysis module 19 detected by temperature sensor 17 is transmitted to control device 80.
[0033] The power supply unit 18 is a device that supplies electricity to the electrolysis module 19 for steam electrolysis. The power supply status from the power supply unit 18 to the electrolysis module 19 is controlled by the control device 80.
[0034] The steam supply unit 20 is a device that generates steam and supplies it to the electrolysis module 19. The steam is supplied to the hydrogen electrode 11 of the electrolysis module 19 through the steam supply pipe 21. The temperature of the hydrogen electrode inlet gas supplied to the hydrogen electrode space 11a is, for example, 200°C or higher.
[0035] The hydrogen separation device 30 is a device for separating hydrogen from a mixture of hydrogen and water vapor generated by the hydrogen electrode 11 of the electrolysis module 19. When the hydrogen discharge valve 31 is open, hydrogen generated by the hydrogen electrode 11 is supplied to the hydrogen separation device 30 via the hydrogen discharge pipe 33. The hydrogen separated by the hydrogen separation device 30 is supplied to the hydrogen storage device 40 via the hydrogen booster 32. The hydrogen separation device 30, for example, cools the mixture of hydrogen and water vapor supplied from the hydrogen discharge pipe 33, causing the water vapor contained in the mixture to condense and be recovered as recycled water.
[0036] The hydrogen storage device 40 is a device that stores hydrogen generated by the electrolysis module 19 and supplies hydrogen to a hydrogen supply destination via the hydrogen supply pipe 41. Additionally, the hydrogen storage device 40 can supply hydrogen to the hydrogen electrode 11 via the hydrogen supply pipe 42 and the steam supply pipe 21. To maintain the hydrogen electrode 11 at a desired temperature, the hydrogen supplied from the hydrogen storage device 40 to the hydrogen electrode 11 is preferably heated during its flow through the hydrogen supply pipe 42 and then supplied to the steam supply pipe 21. Furthermore, the hydrogen storage device 40 can supply hydrogen to the oxygen electrode space 12a of the electrolysis module 19, where the oxygen electrode 12 is located, via the hydrogen supply pipe (fuel gas system) 43.
[0037] The adjustment unit 50 is an apparatus for adjusting the supply amount of water vapor supplied from the water vapor supply unit 20, the supply amount of hydrogen supplied from the hydrogen storage device 40 to the hydrogen electrode 11, the supply amount of hydrogen supplied from the hydrogen storage device 40 to the oxygen electrode 12, the supply amount of air supplied from the air supply unit 70 to the oxygen electrode 12, and the supply amount of air supplied from the air supply unit 70 to the hydrogen electrode 11.
[0038] The adjustment unit 50 includes: a steam adjustment valve 51 disposed on the steam supply pipe 21; a hydrogen adjustment valve 52 disposed on the hydrogen supply pipe 42; a hydrogen adjustment valve (or isolation valve) 53 disposed on the downstream side of the hydrogen supply pipe 42 near the steam supply pipe 21; an air adjustment valve 54 disposed on the air supply pipe 72; an air-side discharge adjustment valve 55 for hydrogen electrode venting gas disposed on the air discharge pipe 73; a hydrogen supply valve 56; and an air adjustment valve 57.
[0039] The hydrogen regulating valve 53 is a valve that is closed when water vapor is supplied to the hydrogen electrode but no hydrogen is supplied. By closing the hydrogen regulating valve 53, water vapor can be prevented from entering the hydrogen supply pipe 42 when water vapor is supplied to the hydrogen electrode but no hydrogen is supplied.
[0040] Hydrogen supply valve 56 is a valve that adjusts the amount of hydrogen supplied from hydrogen storage device 40 to oxygen electrode 12 via hydrogen supply pipe 43 and air supply pipe 74. Hydrogen supplied to air supply pipe 74 is supplied to the oxygen electrode 12 side of electrolysis module 19. Hydrogen supplied to oxygen electrode space 12a of electrolysis module 19 is burned through catalysis, causing the temperature of electrolysis module 19 to rise.
[0041] Figure 1 The hydrogen generation system 100 shown supplies hydrogen stored in the hydrogen storage device 40 to the oxygen electrode space 12a by setting the hydrogen supply valve 56 to the open state, but other methods are also possible. For example, a fuel supply unit (not shown) that supplies hydrogen or other fuel gases (methane gas, etc.) may be provided, and fuel gas is supplied from the fuel supply unit to the oxygen electrode space 12a of the electrolysis module 19, where it is combusted through catalysis.
[0042] The air supply unit 70 is a device that supplies air (heating medium) heated to a high temperature (e.g., less than 400°C) to the oxygen electrode 12. Specifically, the air supplied from the air supply unit 70 is supplied to the oxygen electrode space 12a of the electrolysis module 19 via the air supply pipe 74. Additionally, the air supplied from the air supply unit 70 can be supplied to the hydrogen electrode space 11a via the hydrogen electrode air supply pipe (heating medium supply system) 72. The amount of air supplied from the air supply unit 70 to both the oxygen electrode 12 and the hydrogen electrode 11 is adjusted by the air regulating valve 57. The amount of air supplied from the air supply unit 70 to the hydrogen electrode 11 is adjusted by the air regulating valve 54. It should be noted that "supplying a medium (air, etc.) to the oxygen electrode 12" means supplying the medium to the oxygen electrode 12 by allowing the medium to circulate in the space outside the oxygen electrode 12 of the battery stack CS.
[0043] The control device 80 is a device for controlling the hydrogen generation system 100. The control device 80 has a storage unit (not shown) for storing control programs and an arithmetic unit (not shown) for executing programs. The arithmetic unit executes the programs read from the storage unit to perform various actions to control the hydrogen generation system 100.
[0044] Next, refer to Figure 3 The details of the electrolysis module 19 are explained below. Figure 3 yes Figure 1 The image shows a longitudinal sectional view of the electrolysis module 19. (See attached image.) Figure 3 As shown, the electrolysis module 19 includes multiple electrolytic cells 10, a water vapor supply manifold 217, a hydrogen discharge manifold 219, an air supply manifold 221, and an oxygen discharge manifold 223.
[0045] Additionally, the electrolysis module 19 includes an upper tube sheet 225a, a lower tube sheet 225b, an upper heat insulation body 227a, a lower heat insulation body 227b, and a side heat insulation body 227c. It should be noted that, in this embodiment, the electrolysis module 19 utilizes, as... Figure 3 The water vapor supply manifold 217, hydrogen discharge manifold 219, air supply manifold 221, and oxygen discharge manifold 223 are configured in such a way that water vapor and air flow relative to each other inside and outside the electrolytic cell 10. However, this is not mandatory. For example, they can also flow parallel to each other inside and outside the electrolytic cell 10, or the air can flow in a direction orthogonal to the length direction of the electrolytic cell 10.
[0046] The reaction chamber 215 is a space formed between the upper heat insulation body 227a, the lower heat insulation body 227b, and the side heat insulation body 227c. The reaction chamber 215 is the area where the electrolytic cell 10 is disposed, and hydrogen and oxygen are generated through a steam electrolysis reaction using steam. Additionally, the temperature near the center of the battery stack CS along its length in the reaction chamber 215 can be monitored using a temperature measuring unit (temperature sensor, thermocouple, etc.). During stable operation of the electrolysis module 19, the area near the center of the battery stack CS along its length in the reaction chamber 215 becomes a high-temperature atmosphere of approximately 700°C to 1000°C.
[0047] The steam supply manifold 217 is the area surrounded by the upper housing 229a and the upper tube sheet 225a of the electrolysis module 19, and is connected to the steam supply pipe 21 through a steam supply hole 231a provided on the upper part of the upper housing 229a. In addition, multiple battery stacks CS are connected to the upper tube sheet 225a through a sealing member 237a, and the steam supply manifold 217 guides the steam supplied from the steam supply pipe 21 through the steam supply hole 231a into the interior of the base tube 14 of the multiple battery stacks CS at a substantially uniform flow rate.
[0048] The hydrogen discharge manifold 219 is the area surrounded by the lower housing 229b and the lower tube sheet 225b of the electrolysis module 19, and is connected to the hydrogen discharge pipe 33 through the hydrogen discharge port 231b provided in the lower housing 229b. In addition, multiple electrolysis cells 10 are connected to the lower tube sheet 225b through sealing members 237b. The hydrogen discharge manifold 219 collects the hydrogen and water vapor discharged from the interior of the base tube 14 of the multiple cell stacks CS and guides them to the hydrogen discharge pipe 33 through the hydrogen discharge port 231b.
[0049] The air supply manifold 221 is the area surrounded by the lower housing 229b, lower tube sheet 225b, and lower insulation 227b of the electrolysis module 19. It is connected to the air supply pipe 74 through an air supply hole 233a provided on the side of the lower housing 229b. The air supply manifold 221 guides a predetermined flow rate of air supplied from the air supply pipe 74 through the air supply hole 233a to the reaction chamber 215 through the air supply gap 235a.
[0050] The oxygen discharge manifold 223 is the area surrounded by the upper shell 229a, upper tube sheet 225a, and upper insulation 227a of the electrolysis module 19. It is connected to the oxygen discharge pipe 76 through an oxygen discharge hole 233b located on the side of the upper shell 229a. The oxygen-enriched air discharged from the reaction chamber 215 through the oxygen discharge gap 235b is guided to the oxygen discharge pipe 76 through the oxygen discharge hole 233b.
[0051] The upper tube sheet 225a is located between the top plate of the upper housing 229a and the upper heat insulation body 227a, and is fixed to the side plate of the upper housing 229a in a manner that is substantially parallel to the upper tube sheet 225a, the top plate of the upper housing 229a, and the upper heat insulation body 227a. Furthermore, the upper tube sheet 225a has multiple holes corresponding to the number of battery stacks CS included in the electrolysis module 19, and battery stacks CS are inserted into these holes. The upper tube sheet 225a airtightly supports one end of the multiple battery stacks CS via either or both of a sealing member 237a and an adhesive member, and isolates the water vapor supply manifold 217 from the oxygen exhaust manifold 223.
[0052] The upper heat insulation body 227a is located at the lower end of the upper housing 229a, and is arranged substantially parallel to the top plate of the upper housing 229a and the upper tube sheet 225a, and is fixed to the side plate of the upper housing 229a. Furthermore, the upper heat insulation body 227a has multiple holes corresponding to the number of battery stacks CS included in the electrolysis module 19. The diameter of these holes is set to be larger than the outer diameter of the battery stacks CS. The upper heat insulation body 227a has an oxygen venting gap 235b formed between the inner surface of these holes and the outer surface of the battery stacks CS inserted into the upper heat insulation body 227a.
[0053] The upper heat insulation 227a separates the reaction chamber 215 from the oxygen exhaust manifold 223, suppressing the high temperature of the atmosphere surrounding the upper tube sheet 225a, reducing its strength, and increasing corrosion caused by oxidants in the air. Furthermore, to suppress thermal deformation of the upper tube sheet 225a and other components exposed to the high temperature within the reaction chamber 215 due to temperature differences, a high-temperature durable metal material such as a Ni-based alloy can be used. Additionally, the upper heat insulation 227a guides the oxygen-rich air exposed to high temperatures through the reaction chamber 215 to the oxygen exhaust manifold 223 via the oxygen exhaust gap 235b.
[0054] According to this embodiment, with the structure of the electrolysis module 19 described above, water vapor and oxygen-enriched air flow relative to each other inside and outside the battery stack CS. As a result, heat exchange occurs between the oxygen-enriched air and the water vapor supplied to the reaction chamber 215 through the interior of the base tube 14 of the battery stack CS. The upper tube sheet 225a, etc., made of metallic material, is cooled to a temperature that prevents deformation such as buckling and is supplied to the oxygen discharge manifold 223. Furthermore, the water vapor is heated through heat exchange with the oxygen-enriched air discharged from the reaction chamber 215 and is supplied to the reaction chamber 215 in the form of flowing inside the base tube 14. As a result, water vapor preheated to a temperature suitable for power generation can be supplied to the reaction chamber 215 without the use of heaters or the like.
[0055] The lower tube sheet 225b is located between the bottom plate of the lower housing 229b and the lower heat insulation body 227b, and is fixed to the side plate of the lower housing 229b in a manner that is substantially parallel to the lower tube sheet 225b, the bottom plate of the lower housing 229b, and the lower heat insulation body 227b. Furthermore, the lower tube sheet 225b has multiple holes corresponding to the number of battery stacks CS in the electrolysis module 19, and battery stacks CS are inserted into these holes. The lower tube sheet 225b hermetically supports the other end of the multiple battery stacks CS via either or both of the sealing member 237b and the adhesive member, and isolates the hydrogen exhaust manifold 219 from the air supply manifold 221.
[0056] The lower heat insulation body 227b is arranged substantially parallel to the lower heat insulation body 227b, the bottom plate of the lower housing 229b, and the lower tube sheet 225b at the upper end of the lower housing 229b, and is fixed to the side plate of the lower housing 229b. Furthermore, the lower heat insulation body 227b has multiple holes corresponding to the number of battery stacks CS included in the electrolysis module 19. The diameter of these holes is set to be larger than the outer diameter of the electrolysis cell 10. The lower heat insulation body 227b has an air supply gap 235a formed between the inner surface of these holes and the outer surface of the battery stacks CS inserted into the lower heat insulation body 227b.
[0057] The lower heat insulation 227b separates the reaction chamber 215 from the air supply manifold 221, suppressing the high temperature of the atmosphere surrounding the lower tube sheet 225b, reducing its strength, and increasing corrosion caused by oxidants in the air. The lower tube sheet 225b is made of a metal material with high-temperature durability, such as an Inconel alloy, to prevent thermal deformation caused by the large temperature difference within the lower tube sheet 225b due to exposure to high temperatures. In addition, the lower heat insulation 227b directs the air supplied to the air supply manifold 221 through the air supply gap 235a to the reaction chamber 215.
[0058] According to this embodiment, through the structure of the electrolysis module 19 described above, hydrogen containing water vapor and air flow relative to each other inside and outside the battery stack CS. As a result, the hydrogen containing water vapor, passing through the interior of the base tube 14 of the battery stack CS and through the reaction chamber 215, exchanges heat with the air supplied to the reaction chamber 215. The lower tube sheet 225b, etc., made of metallic material, is cooled to a temperature that prevents deformation such as buckling and is supplied to the hydrogen discharge manifold 219. Furthermore, the air is heated through heat exchange with the hydrogen containing water vapor and supplied to the reaction chamber 215. Consequently, air heated to the temperature required for power generation can be supplied to the reaction chamber 215 without the use of heaters or the like.
[0059] Next, the control actions performed by the control device 80 in this embodiment when the electrolysis module 19 is started will be described. Figure 4 and Figure 5 This is a flowchart showing the control actions when the hydrogen generation system 100 is started.
[0060] In step S101, the control device 80 initiates the supply of air to the substrate tube 14 (hydrogen electrode 11) and the oxygen electrode 12. The control device 80 controls the adjustment unit 50 to open the air adjustment valve 54 and the air-side discharge adjustment valve 55, and to close the water vapor adjustment valve 51, the hydrogen adjustment valve 52, and the hydrogen adjustment valve (or isolation valve) 53. Additionally, the control device 80 opens the air adjustment valve 57 and closes the hydrogen discharge valve 31 and the hydrogen supply valve 56.
[0061] Air supplied from the air supply unit 70 to the oxygen electrode 12 heats the oxygen electrode 12 and the entire electrolysis module 19 before being discharged to the outside. The air supply pipe (heating medium supply system) 72 is a system that supplies air from the air supply unit 70 to the hydrogen electrode 11. Air supplied from the air supply unit 70 to the base tube 14 via the air supply pipe 72 heats the base tube 14 and the entire electrolysis module 19, including the hydrogen electrode 11, before being discharged to the outside via the air discharge pipe 73.
[0062] In step S102, the control device 80 determines whether the temperature Ta of the electrolysis module 19 detected by the temperature sensor 17 exceeds Temp1, and in response to the temperature Ta exceeding Temp1, proceeds to step S103. Temp1 is set to a temperature higher than the dew point of water vapor in the hydrogen electrode 11 so that water vapor does not condense internally. Temp1 is, for example, a temperature above 150°C and below 200°C. Temp2, described later, is set to a temperature higher than Temp1.
[0063] In step S103, the control device 80 causes the air regulating valve 54 to close from the open state, thereby stopping the supply of air from the air supply unit 70 to the base tube 14 (hydrogen electrode 11).
[0064] Next, in step S104, the control device 80 opens the steam regulating valve 51 from the closed state to start supplying steam from the steam supply unit 20 to the hydrogen electrode 11.
[0065] As described above, when the hydrogen generation system 100 is started, when the temperature Ta of the electrolysis module 19 exceeds Temp1, the control device 80 controls the adjustment unit 50 to change from a state in which air is supplied to the substrate tube 14 from the air supply unit 70 without supplying water vapor to the substrate tube 14 from the water vapor supply unit 20 to a state in which water vapor is supplied from the water vapor supply unit 20 without supplying air to the substrate tube 14, thereby completing the oxygen removal on the hydrogen electrode 11 side.
[0066] In step S105, the control device 80 determines whether the temperature Ta of the electrolysis module 19 detected by the temperature sensor 17 exceeds Temp2. If the temperature Ta exceeds Temp2, the process proceeds to step S106. The temperature Temp2 is lower than the oxidation temperature of the metal components contained in the hydrogen electrode 11. Temp2 is, for example, a temperature above 350°C and below 400°C. Temp2 is set to be lower than the temperature at which the oxidation rate of the metal components contained in the hydrogen electrode 11 reacts with water vapor and increases significantly.
[0067] In step S106, the control device 80 starts supplying hydrogen from the hydrogen storage device 40 to the substrate tube 14 (hydrogen electrode 11), and switches the hydrogen regulating valve 52 and the hydrogen regulating valve (or isolation valve) 53 from the closed state to the open state, so that the hydrogen concentration at the inlet of the substrate tube 14 becomes a specified value.
[0068] Next, in step S107, the control device 80 adjusts the opening of the steam regulating valve 51 to adjust the amount of steam supplied from the steam supply unit 20 to the substrate tube 14 (hydrogen electrode 11) so that the steam concentration at the inlet of the substrate tube 14 is a predetermined value.
[0069] As described above, when the hydrogen generation system 100 is started, if the temperature Ta of the electrolysis module 19 exceeds Temp2, the control device 80 controls the adjustment unit 50 to switch from a steam supply state to a state mixed with hydrogen as a reducing gas. By switching from a steam supply state to a state mixed with hydrogen as a reducing gas, the hydrogen electrode 11 is maintained in a reducing state, thus preventing steam oxidation of the hydrogen electrode caused by oxygen contained in the steam.
[0070] In step S108, the control device 80 determines whether the temperature Ta of the electrolysis module 19 detected by the temperature sensor 17 exceeds Temp3. If the temperature Ta exceeds Temp3, the process proceeds to step S109. Temp3 is, for example, a temperature above 300°C and below 500°C. It should be noted that Temp3 is preferably set to the temperature of the highest temperature region in the space where the oxygen electrode 12 is located, i.e., the reaction chamber 215.
[0071] In step S109, the control device 80 switches the hydrogen supply valve 56 from the closed state to the open state to begin supplying hydrogen from the hydrogen storage device 40 to the oxygen electrode 12. The hydrogen supplied to the oxygen electrode 12 of the electrolysis module 19 is burned by the catalytic action of the oxygen electrode 12, causing the temperature on the oxygen electrode 12 side of the electrolysis module 19 to rise.
[0072] The control device 80 controls the opening of the hydrogen supply valve 56 of the hydrogen supply pipe 43 to adjust the hydrogen supply amount so that, during the period from the start of hydrogen supply to the oxygen electrode 12 in step S109 to the cessation of hydrogen supply to the oxygen electrode 12 in step S114, the hydrogen in the air supply manifold 221 before the supply to the oxygen electrode 12 is made to have a non-flammable concentration (less than the lower flammability limit concentration).
[0073] Furthermore, the control device 80 adjusts the mixed gas flow rate and hydrogen concentration by controlling the opening of the hydrogen supply valve 56 and the air adjustment valve 57 to control the hydrogen supply amount and air supply amount, so that the flame propagation speed of the hydrogen supplied to the oxygen electrode 12 is lower than the flow speed of the air-hydrogen mixture supplied to the oxygen electrode 12. Specifically, it is preferable that the flame propagation speed is lower than the flow speed of the gas (oxidizing gas containing water vapor) after combustion due to catalytic action through the oxygen discharge gap 235b. In addition, the amount of hydrogen supplied to the oxygen electrode 12 can also be set by the Joule heat generated by the energization.
[0074] It should be noted that, during the period from when hydrogen supply begins in step S109 and reaches the predetermined hydrogen concentration until the supply is stopped in step S114, the hydrogen flow rate supplied to the oxygen electrode 12 can be gradually reduced to decrease the hydrogen concentration. For example, the hydrogen concentration can be reduced based on the temperature of the area in the space where the oxygen electrode 12 is located, i.e., the reaction chamber 215, which is the area with the highest temperature (e.g., the area near the center of the vertical direction of the reaction chamber 215). In addition, to prevent abnormal temperature rise of the reaction chamber 215 during the supply of hydrogen to the oxygen electrode 12, the temperature of the area in the space where the oxygen electrode 12 is located, i.e., the reaction chamber 215, which is the area with the lowest temperature (e.g., the temperature near the air supply gap 235a, or the temperature near the lower vertical direction of the reaction chamber 215), the temperature of the air supply manifold 221, or the temperature of the hydrogen discharge port 231b, which is at the same temperature, can be detected to control the hydrogen flow rate supplied to the oxygen electrode 12.
[0075] In step S110, the control device 80 determines whether the temperature Ta of the electrolysis module 19 detected by the temperature sensor 17 exceeds Temp4 (a first predetermined temperature). When the temperature Ta exceeds Temp4, the process proceeds to step S111. Temp4 is a temperature lower than the ignition temperature of hydrogen (fuel gas), for example, a temperature above 500°C and below 600°C.
[0076] Temperature sensor 17, which measures Temp4, detects the temperature of the lowest temperature region within the reaction chamber 215 where the electrolytic cell 10 is located. This lowest temperature region is, for example, the area near the air supply gap 235a. Control device 80 controls power supply unit 18 to begin supplying power to electrolysis module 19 in response to the temperature of the lowest temperature region within the space (reaction chamber 215) where the electrolytic cell 10 is located exceeding Temp4. Alternatively, temperature sensor 17 may also detect the temperature of the area near the vertical center of reaction chamber 215, setting Temp4 as the temperature of the lowest temperature region within reaction chamber 215, which is, for example, a temperature above 500°C and below 600°C.
[0077] In step S111, the control device 80 increases the amount of steam supplied from the steam supply unit 20 to the hydrogen electrode 11 in a manner that meets the electrolysis start conditions. The control device 80 adjusts the opening of the steam regulating valve 51 and the opening of the hydrogen regulating valve 52, which controls the amount of hydrogen supplied from the hydrogen storage device 40 to the hydrogen electrode 11, so that the inlet hydrogen concentration in the substrate tube 14 (hydrogen electrode 11) meets the electrolysis start conditions.
[0078] In step S112, the control device 80 controls the power supply unit 18 to begin supplying power from the power supply unit 18 to the electrolysis module 19 and gradually increases the current. When power is supplied from the power supply unit 18 to the electrolysis module 19, Joule heat is generated in the electrolytic cell 10, and the temperature of the reaction chamber 215 rises. The electrolysis module 19, powered by the power supply unit 18, begins to generate hydrogen and oxygen through steam electrolysis.
[0079] In step S113, the control device 80 determines whether the temperature Ta of the electrolysis module 19 detected by the temperature sensor 17 exceeds Temp5 (the second specified temperature), or whether the current supplied to the electrolysis module 19 exceeds a specified value. When either condition is met, the process proceeds to step S114. Temp5 is, for example, set to a temperature above 700°C and below 850°C, which is lower than the temperature at which the electrolysis module 19 operates under rated load.
[0080] In step S114, the control device 80 switches the hydrogen supply valve 56 from the open state to the closed state to stop the supply of hydrogen from the hydrogen storage device 40 to the oxygen electrode 12.
[0081] Temperature sensor 17, which measures Temp5, detects the temperature of the region in the reaction chamber 215 where the electrolytic cell 10 is located, which is the hottest area. This hottest region is, for example, the area near the center of the reaction chamber 215 in the vertical direction. Control device 80 controls hydrogen supply valve 56 to stop supplying hydrogen to oxygen electrode 12 in response to the temperature of the region in the space (reaction chamber 215) where the electrolytic cell 10 is located exceeding Temp5.
[0082] Subsequently, in step S115, it is determined whether the current supplied to the electrolysis module 19 has reached the rated value. If the determination is "yes", the startup is completed at that moment, and the electrolysis module 19 reaches its rated operating state. It should be noted that before the current reaches the rated value, the control device 80 controls the steam regulating valve 51 and the hydrogen regulating valve 52 to ensure that the steam supply to the hydrogen electrode 11 and the inlet hydrogen concentration in the substrate tube 14 (hydrogen electrode 11) meet the rated conditions. Here, the opening degree of the steam regulating valve 51 and the hydrogen regulating valve 52 can also be controlled as a function of the current.
[0083] The function and effects of the hydrogen generation system 100 of this embodiment described above will be explained.
[0084] According to the hydrogen generation system 100 of this embodiment, even if the heat generated by the combustion of hydrogen due to the catalytic action of the oxygen electrode 12 is insufficient, the system starts to supply power to the electrolysis module 19 in response to the temperature of the electrolysis module 19 exceeding Temp4 (a first predetermined temperature) which is lower than the ignition temperature of hydrogen. Therefore, the temperature of the electrolysis module 19 can be appropriately increased by utilizing the Joule heat generated by the power supply, thereby shortening the start-up time.
[0085] According to the hydrogen generation system 100 of this embodiment, the concentration of hydrogen is controlled to be such that it is not ignitable before being supplied to the oxygen electrode 12, thus preventing the adverse situation of hydrogen ignition in the area before being supplied to the oxygen electrode 12 and damage to its surroundings.
[0086] According to the hydrogen generation system 100 of this embodiment, by setting Temp4 to 500°C or higher and less than 600°C, the adverse situation of hydrogen ignition can be reliably prevented.
[0087] According to the hydrogen generation system 100 of this embodiment, by responding to the temperature of the lowest temperature region in the reaction chamber 215 where the electrolysis cell 10 is disposed exceeding Temp4, power is supplied to the electrolysis module 19. Power can be supplied to the electrolysis module 19 at an appropriate time, so that the temperature of the electrolysis module 19 rises appropriately and the start-up time is shortened.
[0088] According to the hydrogen generation system 100 of this embodiment, by stopping the supply of hydrogen to the oxygen electrode 12 in response to the temperature of the electrolysis module 19 exceeding Temp5, which is higher than Temp4, the temperature of the electrolysis module 19 can be appropriately increased by utilizing the heat generated by the combustion of hydrogen caused by the catalytic action of the oxygen electrode 12.
[0089] According to the hydrogen generation system 100 of this embodiment, by stopping the supply of hydrogen to the oxygen electrode 12 in response to the temperature of the region that is the highest temperature in the reaction chamber 215 where the electrolytic cell 10 is disposed exceeding Temp5, the temperature of the electrolysis module 19 can be appropriately increased by utilizing the heat generated by the combustion of hydrogen caused by the catalytic action of the oxygen electrode 12.
[0090] According to the hydrogen generation system 100 of this embodiment, since Temp5 is set to be lower than the temperature when the electrolysis module 19 is operating at its rated load, the supply of hydrogen to the oxygen electrode 12 can be reliably stopped before the electrolysis module 19 is operating at its rated load.
[0091] According to the hydrogen generation system 100 of this embodiment, by setting Temp5 to 700°C or higher and 850°C or lower, the supply of hydrogen to the oxygen electrode 12 can be reliably stopped before the electrolysis module 19 operates at its rated load.
[0092] According to the hydrogen generation system 100 of this embodiment, the flame propagation speed of the hydrogen supplied to the oxygen electrode 12 is lower than the flow speed of the air supplied to the oxygen electrode 12. Therefore, even if the hydrogen is ignited, the flame can be prevented from propagating to the outside and causing external damage.
[0093] According to the hydrogen generation system 100 of this embodiment, hydrogen generated by steam electrolysis can be supplied to the oxygen electrode 12 as fuel gas, and the temperature of the electrolysis module 19 can be appropriately increased by utilizing the heat generated by the combustion of hydrogen caused by the catalytic action of the oxygen electrode 12.
[0094] The hydrogen generation system (100) and the control method of the hydrogen generation system described in the above embodiments are as follows.
[0095] The hydrogen generation system of the first aspect of this disclosure comprises: an electrolysis module (19) having an electrolytic cell 10 having a hydrogen electrode, an oxygen electrode and an electrolyte layer disposed between the hydrogen electrode and the oxygen electrode, the electrolysis module (19) supplying water vapor to the hydrogen electrode and generating hydrogen by electrolysis of the water vapor; a water vapor supply unit (20) supplying the water vapor to the hydrogen electrode; an air supply unit (70) supplying air to the oxygen electrode; a fuel gas system (43) supplying fuel gas to the oxygen electrode; a power supply unit 18 supplying power to the electrolysis module; and a control unit (80) controlling the hydrogen generation system, the control unit controlling the power supply unit to start supplying power to the electrolysis module in response to the temperature of the electrolysis module exceeding a first predetermined temperature lower than the ignition temperature of the fuel gas.
[0096] According to the hydrogen generation system of the first aspect of this disclosure, even if the heat generated by the combustion of fuel gas due to the catalytic action of the oxygen electrode is insufficient, power is supplied to the electrolysis module in response to the temperature of the electrolysis module exceeding a first predetermined temperature lower than the ignition temperature of the fuel gas. Therefore, the temperature of the electrolysis module can be appropriately increased, thereby shortening the start-up time.
[0097] The hydrogen generation system of the second aspect of this disclosure, based on the first aspect, further includes the following structure: The control unit controls the fuel gas system to ensure that the fuel gas supplied to the oxygen electrode has a non-ignition concentration.
[0098] According to the hydrogen generation system of the second aspect of this disclosure, the concentration of fuel gas before it is supplied to the oxygen electrode is controlled to prevent ignition, thus preventing the adverse situation of fuel gas ignition in the area before it is supplied to the oxygen electrode and damage to its surroundings.
[0099] The third-party hydrogen generation system disclosed herein, in addition to the first or second method, further comprises the following structure: The first specified temperature is above 500°C and below 600°C.
[0100] According to the third-party hydrogen generation system disclosed herein, by setting the first specified temperature to above 500°C and below 600°C, adverse conditions such as fuel gas ignition can be reliably prevented.
[0101] The fourth hydrogen generation system disclosed herein, based on the first or second embodiment, further comprises the following structure: The control unit controls the fuel gas system to begin supplying fuel gas to the oxygen electrode in response to the temperature of the region that becomes the highest temperature in the space where the electrolytic cell is located.
[0102] According to the fourth aspect of the hydrogen generation system disclosed herein, fuel gas can be supplied to the oxygen electrode in response to the temperature of the region that becomes the highest temperature in the space where the electrolytic cell is located.
[0103] The fifth hydrogen generation system of this disclosure, based on the first or second embodiment, further comprises the following structure: The control unit controls the power supply unit to begin supplying power to the electrolysis module in response to the temperature of the lowest temperature region in the space where the electrolysis cell is located exceeding the first predetermined temperature.
[0104] According to the fifth aspect of the hydrogen generation system disclosed herein, by responding to the temperature of the lowest temperature region in the space where the electrolytic cell is configured exceeding a first predetermined temperature, power is supplied to the electrolytic module at an appropriate time, thereby causing the temperature of the electrolytic module to rise appropriately and shortening the start-up time.
[0105] The sixth hydrogen generation system of this disclosure, based on the first or second embodiment, further comprises the following structure: The control unit controls the fuel gas system to stop supplying fuel gas to the oxygen electrode in response to the temperature of the electrolysis module exceeding a second predetermined temperature higher than the first predetermined temperature.
[0106] According to the sixth aspect of the hydrogen generation system disclosed herein, by stopping the supply of fuel gas to the oxygen electrode in response to the temperature of the electrolysis module exceeding a second predetermined temperature higher than a first predetermined temperature, the temperature of the electrolysis module can be appropriately increased by utilizing the heat generated by the combustion of the fuel gas caused by the catalytic action of the oxygen electrode.
[0107] The hydrogen generation system of the seventh embodiment disclosed herein, based on the sixth embodiment, further includes the following structure: The control unit controls the fuel gas system to stop supplying fuel gas to the oxygen electrode in response to the temperature of the region in the space where the electrolytic cell is located, which is the highest temperature region, exceeding the second predetermined temperature.
[0108] According to the hydrogen generation system of the seventh aspect of this disclosure, by stopping the supply of fuel gas to the oxygen electrode in response to the temperature of the region that is the highest temperature in the space where the electrolytic cell is located exceeding a second predetermined temperature, the temperature of the electrolysis module can be appropriately increased by utilizing the heat generated by the combustion of the fuel gas caused by the catalytic action of the oxygen electrode.
[0109] The hydrogen generation system of the eighth method disclosed herein, based on the sixth method, further comprises the following structure: The second predetermined temperature is set lower than the temperature at which the electrolysis module operates under rated load.
[0110] According to the hydrogen generation system of the eighth aspect of this disclosure, the second specified temperature is set lower than the temperature at which the electrolysis module operates at its rated load, so that the supply of fuel gas to the oxygen electrode can be reliably stopped before the electrolysis module operates at its rated load.
[0111] The hydrogen generation system of the ninth method disclosed herein, based on the sixth method, further comprises the following structure: The second specified temperature is above 700°C and below 850°C.
[0112] According to the hydrogen generation system of the ninth aspect of this disclosure, by setting the second specified temperature to above 700°C and below 850°C, the supply of fuel gas to the oxygen electrode can be reliably stopped before the electrolysis module is operating at rated load.
[0113] The hydrogen generation system of the tenth aspect of this disclosure, based on the first or second aspect, further comprises the following structure: The control unit controls the fuel gas system and the heating medium supply unit such that the flame propagation speed of the fuel gas supplied to the oxygen electrode is lower than the flow speed of the air supplied to the oxygen electrode.
[0114] According to the hydrogen generation system of the tenth aspect of this disclosure, the flame propagation speed of the fuel gas supplied to the oxygen electrode is lower than the flow speed of the air supplied to the oxygen electrode. Therefore, even if the fuel gas is ignited, the flame can be prevented from propagating to the outside and causing external damage.
[0115] The hydrogen generation system of the eleventh aspect of this disclosure, based on the first or second aspect, further comprises the following structure: The fuel gas system supplies hydrogen to the oxygen electrode as the fuel gas.
[0116] According to the hydrogen generation system of the eleventh aspect of this disclosure, hydrogen generated by steam electrolysis can be supplied to the oxygen electrode as fuel gas, and the temperature of the electrolysis module can be appropriately increased by utilizing the heat generated by the combustion of hydrogen caused by the catalytic action of the oxygen electrode.
[0117] The hydrogen generation system of the twelfth aspect of this disclosure, based on the eleventh aspect, further includes the following structure: The control unit controls the fuel gas system to gradually reduce the flow rate of hydrogen supplied to the oxygen electrode during the period from the start of supplying fuel gas to the oxygen electrode until the supply of fuel gas to the oxygen electrode stops.
[0118] The hydrogen generation system of the thirteenth aspect of this disclosure, based on the eleventh aspect, further comprises the following structure: The control unit controls the fuel gas system to detect, during the period from the start of supplying fuel gas to the oxygen electrode to the cessation of supplying fuel gas to the oxygen electrode, any one of the following temperatures: the temperature of the region in the space where the electrolytic cell is located is the lowest temperature; the temperature of the air supply manifold from which air is supplied from the air supply unit; and the temperature of the hydrogen discharge orifice from which hydrogen generated by the electrolysis module is discharged. This allows for the adjustment of the flow rate of hydrogen supplied to the oxygen electrode.
[0119] In the control method of the hydrogen generation system of the fourteenth aspect of this disclosure, the hydrogen generation system comprises: an electrolysis module having an electrolytic cell having a hydrogen electrode, an oxygen electrode, and an electrolyte layer disposed between the hydrogen electrode and the oxygen electrode, the electrolysis module supplying water vapor to the hydrogen electrode and generating hydrogen by electrolysis of the water vapor; a water vapor supply unit supplying the water vapor to the hydrogen electrode; an air supply unit supplying air to the oxygen electrode; a fuel gas system supplying fuel gas to the oxygen electrode; and an electricity supply unit supplying electricity to the electrolysis module. The control method of the hydrogen generation system includes a control step in which the electricity supply unit is controlled to start supplying electricity to the electrolysis module in response to the temperature of the electrolysis module exceeding a first predetermined temperature lower than the ignition temperature of the fuel gas.
[0120] According to the control method of the hydrogen generation system of the fourteenth aspect of this disclosure, even if the heat generated by the combustion of fuel gas due to the catalytic action of the oxygen electrode is insufficient, power is supplied to the electrolysis module in response to the temperature of the electrolysis module exceeding a first predetermined temperature lower than the ignition temperature of the fuel gas. Therefore, the temperature of the electrolysis module can be appropriately increased, thereby shortening the start-up time.
[0121] Explanation of reference numerals in the attached figures:
[0122] 10 Electrolytic cells
[0123] 11 Hydrogen pole
[0124] 11a Hydrogen Polar Space
[0125] 12 Oxygen pole
[0126] 12a Oxygen Polar Space
[0127] 13 Electrolyte layer
[0128] 14. Matrix tube
[0129] 17 Temperature sensor
[0130] 18. Department of Electricity Supply
[0131] 19 Electrolysis Module
[0132] 20. Steam Supply Department
[0133] 21. Steam supply pipe
[0134] 30 Hydrogen Separation Equipment
[0135] 31 Hydrogen discharge valve
[0136] 32 Hydrogen booster
[0137] 33 Hydrogen discharge pipe
[0138] 40 Hydrogen storage equipment
[0139] 41, 42, 43 Hydrogen supply pipes
[0140] 50 Adjustment Department
[0141] 51 Steam regulating valve
[0142] 52, 53 Hydrogen regulating valves
[0143] 54 Air regulating valve
[0144] 55 Air-side discharge volume adjustment valve
[0145] 56 Hydrogen supply valve
[0146] 57 Air regulating valve
[0147] 70 Air Supply Department
[0148] 72 Air supply pipe
[0149] 73 Air exhaust pipe
[0150] 74 Air supply pipe
[0151] 76 Oxygen exhaust pipe
[0152] 80 Control device (control unit)
[0153] 100 Hydrogen Generation System
[0154] 215 Reaction Chamber
[0155] 217 Steam supply manifold
[0156] 219 Hydrogen Discharge Manifold
[0157] 221 Air supply manifold
[0158] 223 Oxygen Discharge Manifold
[0159] 225a upper tube sheet
[0160] 225b lower tube sheet
[0161] 227a Upper insulation
[0162] 227b Lower insulation
[0163] 227c Side insulation
[0164] 229a Upper Shell
[0165] 229b Lower housing
[0166] 231a Steam supply port
[0167] 231b Hydrogen vent
[0168] 233a Air supply port
[0169] 233b Oxygen vent
[0170] 235a Air supply gap
[0171] 235b Oxygen Exhaust Gap
[0172] 237a, 237b Sealing components.
Claims
1. A hydrogen generation system, wherein, The hydrogen generation system comprises: An electrolysis module includes an electrolytic cell having a hydrogen electrode, an oxygen electrode, and an electrolyte layer disposed between the hydrogen electrode and the oxygen electrode. The electrolysis module supplies water vapor to the hydrogen electrode and generates hydrogen by electrolysis of the water vapor. A steam supply unit that supplies steam to the hydrogen electrode; An air supply unit that supplies air to the oxygen electrode; A fuel gas system that supplies fuel gas to the oxygen electrode; The power supply unit supplies power to the electrolysis module; and The control unit controls the hydrogen generation system. The control unit controls the power supply unit to start supplying power to the electrolysis module in response to the temperature of the electrolysis module exceeding a first predetermined temperature lower than the ignition temperature of the fuel gas.
2. The hydrogen generation system according to claim 1, wherein, The control unit controls the fuel gas system to ensure that the fuel gas supplied to the oxygen electrode is at a non-ignition concentration.
3. The hydrogen generation system according to claim 1 or 2, wherein, The first specified temperature is above 500℃ and below 600℃.
4. The hydrogen generation system according to claim 1 or 2, wherein, The control unit controls the fuel gas system to begin supplying fuel gas to the oxygen electrode in response to the temperature of the region that becomes the highest temperature in the space where the electrolytic cell is located.
5. The hydrogen generation system according to claim 1 or 2, wherein, The control unit controls the power supply unit to start supplying power to the electrolysis module in response to the temperature of the lowest temperature region in the space where the electrolytic battery is located exceeding the first predetermined temperature.
6. The hydrogen generation system according to claim 1 or 2, wherein, The control unit controls the fuel gas system to stop supplying fuel gas to the oxygen electrode in response to the temperature of the electrolysis module exceeding a second predetermined temperature higher than the first predetermined temperature.
7. The hydrogen generation system according to claim 6, wherein, The control unit controls the fuel gas system to stop supplying fuel gas to the oxygen electrode in response to the temperature of the region that is the hottest in the space where the electrolytic cell is located exceeding the second predetermined temperature.
8. The hydrogen generation system according to claim 6, wherein, The second specified temperature is set lower than the temperature at which the electrolysis module operates under rated load.
9. The hydrogen generation system according to claim 6, wherein, The second specified temperature is above 700°C and below 850°C.
10. The hydrogen generation system according to claim 1 or 2, wherein, The control unit controls the fuel gas system and the air supply unit so that the flame propagation speed of the fuel gas supplied to the oxygen electrode is lower than the flow speed of the air supplied to the oxygen electrode.
11. The hydrogen generation system according to claim 1 or 2, wherein, The fuel gas system supplies hydrogen to the oxygen electrode as the fuel gas.
12. The hydrogen generation system according to claim 11, wherein, The control unit controls the fuel gas system to gradually reduce the flow rate of hydrogen supplied to the oxygen electrode from the start of supplying fuel gas to the oxygen electrode until the supply of fuel gas to the oxygen electrode stops.
13. The hydrogen generation system according to claim 11, wherein, The control unit controls the fuel gas system to detect, during the period from the start of supplying fuel gas to the oxygen electrode to the stop of supplying fuel gas to the oxygen electrode, any one of the following temperatures: the temperature of the area in the space where the electrolytic cell is located, the temperature of the air supply manifold from which air is supplied from the air supply unit, and the temperature of the hydrogen discharge port from which hydrogen generated by the electrolysis module is discharged, thereby adjusting the flow rate of hydrogen supplied to the oxygen electrode.
14. A control method for a hydrogen generation system, wherein, The hydrogen generation system has the following characteristics: An electrolysis module includes an electrolytic cell having a hydrogen electrode, an oxygen electrode, and an electrolyte layer disposed between the hydrogen electrode and the oxygen electrode. The electrolysis module supplies water vapor to the hydrogen electrode and generates hydrogen by electrolysis of the water vapor. A steam supply unit that supplies steam to the hydrogen electrode; An air supply unit that supplies air to the oxygen electrode; A fuel gas system that supplies fuel gas to the oxygen electrode; and The power supply unit supplies power to the electrolysis module. The control method for the hydrogen generation system includes a control step in which the power supply unit is controlled to begin supplying power to the electrolysis module in response to the temperature of the electrolysis cell exceeding a first predetermined temperature lower than the ignition temperature of the fuel gas.