Heating device

Abstract

To provide a heating device that can reduce the temperature difference between the inner and outer circumferences of a heating element. [Solution] The heating device 3 comprises a heating element 14 formed in an annular shape from a plate-shaped member made of a multilayer film that generates heat by the absorption and release of hydrogen, a sealed container 5 that houses the heating element 14, an introduction line for introducing hydrogen-containing gas into the sealed container 5, an outlet line for releasing the gas that has been used to generate heat in the heating element 14 due to the absorption and release of hydrogen in the heating element 14, an induction coil 15 formed by winding a linear conductive member around the central axis of the heating element 14 on the outer circumference of the sealed container 5, and a power supply 19 that applies an alternating current to the induction coil 15, wherein the power supply 19 is capable of changing the frequency of the alternating current.

Description

Technical Field

[0001] The present invention relates to a heating device.

Background Art

[0002] In recent years, a heating device has been proposed that includes a sealed container supplied with a gas containing hydrogen, a heating element that generates heat by hydrogen absorption and release, and a heater that heats the heating element (see Patent Document 1). The heating element is housed in the internal space of the sealed container. The heating element is formed by winding a plate-like member, and the heater is inserted into the center of the wound heating element. The heating element has a pedestal formed of a hydrogen storage metal, a hydrogen storage alloy, or a proton conductor, and a multilayer film provided on the pedestal. The multilayer film has a first layer with a thickness of less than 1000 nm formed of a hydrogen storage metal or a hydrogen storage alloy, and a second layer with a thickness of less than 1000 nm formed of a hydrogen storage metal, a hydrogen storage alloy, or ceramics different from the first layer. A hetero-substance interface is formed between the first layer and the second layer. In the heating device of Patent Document 1, after hydrogen is absorbed by the heating element, evacuation of the inside of the sealed container and heating of the heating element are performed, so that hydrogen permeates through the hetero-substance interface by quantum diffusion in the heating element, or hydrogen diffuses through the hetero-substance interface by quantum diffusion, generating excess heat.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the heating device disclosed in Patent Document 1, the heater is located in the center of the heating element. As a result, the temperature of the inner circumference of the heating element is higher than the temperature of the outer circumference, creating a temperature difference between the inner and outer circumferences of the heating element. Furthermore, if the heating element generates excess heat, the temperature of the inner circumference of the heating element becomes even higher, increasing the temperature difference between the inner and outer circumferences of the heating element. If the heater temperature is increased to raise the temperature of the outer circumference of the heating element, there is a risk that the heater will exceed its heat resistance temperature or that the temperature of the inner circumference of the heating element will become too high.

[0005] The present invention aims to provide a heating device that can reduce the temperature difference between the inner and outer circumferences of a heating element. [Means for solving the problem]

[0006] The heating device according to the present invention comprises a heating element formed by a plate-shaped member made of a multilayer film that generates heat by the absorption and release of hydrogen, arranged in an annular shape or wound around it; a sealed container housing the heating element; an introduction line for introducing a hydrogen-containing gas into the sealed container; an outlet line for discharging the gas that has been used to generate heat in the heating element due to the absorption and release of hydrogen in the heating element; an induction coil formed by winding a linear conductive member around the central axis of the heating element on the outer circumference of the sealed container; and a power supply for applying an alternating current to the induction coil, wherein the power supply is capable of changing the frequency of the alternating current.

[0007] According to the present invention, it is possible to provide a heating device that can reduce the temperature difference between the inner and outer circumferences of a heating element. [Brief explanation of the drawing]

[0008] [Figure 1] This is a conceptual diagram illustrating the configuration of the heat utilization system according to the first embodiment. [Figure 2] This is an exploded perspective view of the heat-generating structure according to the first embodiment. [Figure 3] This is a cross-sectional view showing the configuration of the heating element. [Figure 4]This graph shows the temperature distribution and eddy current magnitude of the heating structure according to the first embodiment. [Figure 5] This is a conceptual diagram illustrating the configuration of the heat utilization system according to the second embodiment. [Figure 6] This is an exploded perspective view of the heat-generating structure according to the third embodiment. [Figure 7] This is a conceptual diagram illustrating the configuration of the heat utilization system according to the fourth embodiment. [Modes for carrying out the invention]

[0009] Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. In the following description and drawings, common components are denoted by the same reference numerals. Descriptions of components denoted by the same reference numerals will be omitted as appropriate.

[0010] (1) Heating device and heat utilization system according to the first embodiment In Figure 1, the heat utilization system 1 comprises a piping route 2 through which a heat exchange medium flows, a heating device 3 that heats the heat medium flowing through the piping route 2, and a heat utilization device 4 that uses the heat medium heated by the heating device 3 as a heat source. The heating device 3 and the heat utilization device 4 are incorporated into the piping route 2. The piping route 2 forms a circulation path between the heating device 3 and the heat utilization device 4.

[0011] As a heat transfer medium, a gas or liquid can be used, and one with excellent thermal conductivity and chemical stability is preferred. Examples of gases include helium, argon, hydrogen, nitrogen, water vapor, air, and carbon dioxide. Examples of liquids include water, molten salts (such as KNO3 (40%)-NaNO3 (60%)), and liquid metals (such as Pb). Alternatively, a multiphase heat transfer medium in which solid particles are dispersed in a gas or liquid may be used. The solid particles may be metals, metal compounds, alloys, or ceramics. Examples of metals include Cu, Ni, Ti, and Co. Examples of metal compounds include oxides, nitrides, and silicides of the above metals. Examples of alloys include stainless steel and chromium-molybdenum steel. Examples of ceramics include alumina. In this embodiment, helium gas is used as the heat transfer medium, but it can be appropriately changed without departing from the spirit of the present invention.

[0012] The heating device 3 comprises a sealed container 5, a hydrogen tank 6 connected to the sealed container 5, a vacuum pump 7 connected to the sealed container 5, and a heating structure 8 housed in the sealed container 5.

[0013] The sealed container 5 has heat resistance and pressure resistance. The sealed container 5 is made of, for example, stainless steel or heat-resistant non-ferrous alloy steel. The material used for the sealed container 5 is appropriate to the operating temperature. For example, stainless steel is used when the operating temperature is up to about 700°C, and heat-resistant non-ferrous alloy steel is used when the operating temperature exceeds 700°C. The sealed container 5 is formed in a cylindrical shape. The sealed container 5 consists of a body, an upper lid provided at the upper end of the body, and a lower lid provided at the lower end of the body. The upper end of the body is airtightly closed with the upper lid, and the lower end of the body is airtightly closed with the lower lid, thereby partitioning the space 9 inside the sealed container 5. The shape of the sealed container 5 is not limited to a cylindrical shape, but may also be elliptical, rectangular, spherical, etc. In the heating device 3, the upper lid side of the sealed container 5 is considered the upper side, and the lower lid side of the sealed container 5 is considered the lower side. The sealed container 5 houses the heating element 14, which will be described later.

[0014] The heating device 3 has an introduction pipe 10 that connects the sealed container 5 and the hydrogen tank 6, and an exhaust pipe 11 that connects the sealed container 5 and the vacuum pump 7. The introduction pipe 10 extends from the bottom lid of the sealed container 5 and is connected to the hydrogen tank 6, guiding the hydrogen-based gas stored in the hydrogen tank 6 into the internal space 9 of the sealed container 5. The introduction pipe 10 constitutes an introduction line for introducing hydrogen-containing gas (hydrogen-based gas) into the sealed container 5. The exhaust pipe 11 extends from the top lid of the sealed container 5 and is connected to the vacuum pump 7, guiding the hydrogen-based gas that is drawn from the internal space 9 of the sealed container 5 to the vacuum pump 7. The exhaust pipe 11 constitutes an outlet line for dischargering the hydrogen-containing gas (hydrogen-based gas) that has been used to generate heat in the heating element 14 through the absorption and release of hydrogen in the heating element 14, which will be described later.

[0015] The inlet pipe 10 has a supply valve 12 installed between the sealed container 5 and the hydrogen tank 6. The supply valve 12 adjusts the flow rate of the hydrogen-based gas flowing through the inlet pipe 10. For example, an electromagnetic valve or an air valve can be used for the supply valve 12. The inlet pipe 10 may also have a pressure sensor that detects the pressure of the hydrogen-based gas flowing through the inlet pipe 10.

[0016] The exhaust pipe 11 has an exhaust valve 13 provided between the sealed container 5 and the vacuum pump 7. For example, an electromagnetic valve or an air valve can be used for the exhaust valve 13. The exhaust pipe 11 may also have a pressure sensor that detects the pressure in the space 9 inside the sealed container 5 through which the exhaust pipe 11 flows.

[0017] When the exhaust valve 13 is closed and the supply valve 12 is opened, hydrogen-based gas can be supplied from the hydrogen tank 6 to the space 9 inside the sealed container 5. When the supply valve 12 is closed and the exhaust valve 13 is opened, the vacuum pump 7 can discharge the hydrogen-based gas from the space 9 inside the sealed container 5.

[0018] The hydrogen tank 6 stores a hydrogen-based gas. In this example, when the supply valve 12 is opened, the hydrogen-based gas is supplied from the high-pressure hydrogen tank 6 through the introduction pipe 10 into the internal space 9 of the low-pressure sealed container 5. The hydrogen-based gas is a gas containing isotopes of hydrogen. As the hydrogen-based gas, at least one of deuterium gas and light hydrogen gas is used. The light hydrogen gas includes a naturally occurring mixture of light hydrogen and deuterium, that is, a mixture in which the abundance ratio of light hydrogen is 99.985% and the abundance ratio of deuterium is 0.015%. The introduction pipe 10 may have a pump that sends out the hydrogen-based gas stored in the hydrogen tank 6 into the internal space 9 of the sealed container 5.

[0019] The vacuum pump 7 discharges the hydrogen-based gas from the inside of the sealed container 5 through the exhaust pipe 11. By driving the vacuum pump 7, the internal space 9 of the sealed container 5 is depressurized. The vacuum pump 7 is composed of, for example, a turbomolecular pump and a dry pump. The turbomolecular pump adjusts the rotation speed of the turbine blades based on a control signal input from a control unit 21 described later. The depressurization rate of the space 9 is adjusted according to the rotation speed of the turbomolecular pump.

[0020] A part of the piping path 2 is wound around the sealed container 5 to form a coiled pipe 201. The coiled pipe 201 is in contact with the sealed container 5. The heat-generating structure 8 heats the heat medium flowing through the coiled pipe 201 via the sealed container 5. The temperature of the heat medium heated by the heat-generating structure 8 reaches, for example, a range of 50°C or more and 1500°C or less. In this example, the temperature of the heat medium is set to 700°C.

[0021] The coiled pipe 201 has heat insulation and pressure resistance. The coiled pipe 201 is formed of, for example, stainless steel, heat-resistant non-ferrous alloy steel, etc. As the material of the coiled pipe 201, a material corresponding to the use temperature is used. For example, when the use temperature is up to about 700°C, stainless steel is used, and when the use temperature exceeds 700°C, heat-resistant non-ferrous alloy steel is used.

[0022] The heat-generating structure 8 includes a heat-generating element 14 that generates heat by the absorption and release of hydrogen, and a temperature sensor 17 that detects the temperature of the heat-generating element 14.

[0023] The heating element 14 is a plate-shaped member formed in an annular shape, composed of a multilayer film 62 (see Figure 3) that generates heat through the absorption and release of hydrogen, as described later. The heating element 14 is formed in a plate shape with a through hole. In this embodiment, the heating element 14 is formed in an annular shape and has a circular through hole in the center. Multiple heating elements 14 are arranged in a first direction along the central axis CL (see Figure 2) of the through hole. That is, the heating structure 8 comprises multiple heating elements 14 arranged along the first direction. Note that the heating element 14 is not limited to being annular, but may also be polygonal annular, etc. The configuration of the heating element 14 will be described later using another drawing.

[0024] The central axis of the coiled piping 201 approximately coincides with the central axis CL of the through-hole of the heating element 14. In other words, a portion of the piping route 2 is wound around the central axis CL of the heating element 14 on the outer circumference of the sealed container 5, forming the coiled piping 201.

[0025] The temperature sensor 17 outputs a detection signal that identifies the detected temperature. The temperature sensor 17 has, for example, a thermocouple embedded in the heating element 14. The thermocouple outputs a voltage that identifies the detected temperature.

[0026] The heating device 3 includes an induction coil 15 as a heat source for heating the heating element 14, and a power supply 19 for applying an alternating current to the induction coil 15. The power supply 19 is capable of changing the frequency of the alternating current, and can apply a low-frequency (e.g., 60 Hz) alternating current and a high-frequency (e.g., 1 MHz) alternating current to the induction coil 15.

[0027] The induction coil 15 is formed from a linear conductive member installed inside the coiled pipe 201. In other words, the induction coil 15 is formed by winding a linear conductive member around the central axis CL of the heating element 14 on the outer circumference of the sealed container 5. By applying an alternating current to the induction coil 15, eddy currents are generated in the heating element 14, causing the heating element 14 to heat up.

[0028] The induction coil 15 is connected to a conductive wire 18. The conductive wire 18 is connected to a power supply 19, electrically connecting the induction coil 15 and the power supply 19. The induction coil 15 generates eddy currents in the heating element 14 when current is applied from the power supply 19 via the conductive wire 18. The induction coil 15 heats the heating element 14 with the eddy currents. In Figure 1, the conductive wire 18 extends from inside to outside the coiled pipe 201, but it may also extend from outside the pipe. For example, a connection terminal may be provided on the coiled pipe 201, and the connection terminal and the conductive wire 18 may be connected outside the coiled pipe 201, while the induction coil 15 is connected to the connection terminal inside the coiled pipe 201.

[0029] The heating device 3 includes a control unit 21 electrically connected to a vacuum pump 7, a supply valve 12, an exhaust valve 13, a temperature sensor 17, and a power supply 19. The control unit 21 includes, for example, a microprocessor (MPU) that performs arithmetic processing based on application programs stored in read-only memory (ROM) or other storage units, and random access memory (RAM) that temporarily holds programs and data during arithmetic processing.

[0030] The control unit 21 outputs control signals to control the operation of the vacuum pump 7, the supply valve 12, the exhaust valve 13, and the power supply 19, respectively. The vacuum pump 7, the supply valve 12, the exhaust valve 13, and the power supply 19 operate based on the control signals input from the control unit 21.

[0031] The control unit 21 closes the supply valve 12, opens the exhaust valve 13, and drives the vacuum pump 7 to discharge (vacuum evacuum) the hydrogen-based gas from the space 9 inside the sealed container 5.

[0032] The control unit 21 stops the operation of the vacuum pump 7, closes the exhaust valve 13, and opens the supply valve 12, thereby supplying hydrogen-based gas to the space 9 inside the sealed container 5.

[0033] The control unit 21 adjusts the frequency of the alternating current applied from the power supply 19 to the induction coil 15 via the conductive wire 18 by controlling the frequency of the alternating current output from the power supply 19. By controlling the frequency of the alternating current output from the power supply 19, the position of the eddy currents generated by the induction coil 15 is adjusted, which in turn adjusts the temperature distribution of the entire heating element 14 and makes it possible to maintain it within the optimal temperature range for heating (for example, 50°C to 1500°C).

[0034] In the heating device 3, a supply unit is configured to supply hydrogen-containing hydrogen-based gas to the inside of the sealed container 5, consisting of a hydrogen tank 6, an inlet pipe 10, and a supply valve 12. In the heating device 3, an exhaust unit is configured to discharge the hydrogen-based gas from inside the sealed container 5, consisting of a vacuum pump 7, an exhaust pipe 11, and an exhaust valve 13.

[0035] The heat utilization device 4 includes a power generation unit 42 that generates electricity based on a heat transfer medium (helium gas in this example) heated by the heat generation device 3, a pressure pump 43 that sends the heat transfer medium from the power generation unit 42 to the coiled pipe 201, and a flow control valve 44 provided between the pressure pump 43 and the coiled pipe 201.

[0036] The heat transfer fluid that flows into the coiled pipe 201 is heated by the heat-generating structure 8 housed in the sealed container 5. The temperature of the heat transfer fluid rises inside the coiled pipe 201, resulting in a high-temperature heat transfer fluid. The high-temperature heat transfer fluid flows out of the coiled pipe 201 and into the power generation unit 42.

[0037] The power generation unit 42 includes a compressor (not shown) that compresses a high-temperature heat transfer medium supplied from a coiled pipe 201, a gas turbine 42a driven by the high-temperature and high-pressure heat transfer medium compressed by the compressor, and a generator 42b connected to the gas turbine 42a. In the power generation unit 42, the temperature of the heat transfer medium is adjusted to a range of, for example, 600°C to 1500°C. The output shaft of the gas turbine 42a is connected to the input shaft of the generator 42b. The rotation of the turbine blades of the gas turbine 42a drives the rotor of the generator 42b, and the generator 42b generates electricity. The heat transfer medium from which heat has been utilized in the power generation unit 42 flows out of the power generation unit 42 and into the pressure pump 43.

[0038] The pressure pump 43 sends the heat transfer medium supplied from the power generation unit 42 towards the coiled piping 201 at a predetermined pressure. For example, a metal bellows pump is used for the pressure pump 43.

[0039] The flow control valve 44 adjusts the flow rate of the heat transfer medium flowing from the pressure pump 43 to the coiled piping 201. For example, a variable leak valve is used for the flow control valve 44.

[0040] Figure 2 is an exploded perspective view of the heating structure 8 according to the first embodiment. As shown in Figure 2, the heating structure 8 includes rod-shaped members 20 arranged in through holes of a plurality of heating elements 14. The rod-shaped members 20 are formed in a cylindrical or columnar shape. In this embodiment, the rod-shaped members 20 are formed in a cylindrical shape and have a uniform diameter along the entire length in a first direction along the central axis of the rod-shaped members 20. Note that "uniform" includes not only cases where it is strictly uniform, but also cases where it is substantially uniform, that is, cases where it differs within the scope that does not depart from the spirit of the invention. The shape of the rod-shaped members 20 is not limited to the case where it is cylindrical, but may be other appropriate shapes such as an elliptical tube or a rectangular tube.

[0041] The rod-shaped member 20 has an outer circumferential surface 20a surrounded by the heating element 14. In this embodiment, the outer circumferential surface 20a is a cylindrical surface. The central axis of the rod-shaped member 20 substantially coincides with the central axis CL of the heating element 14.

[0042] The heating element 14 has an inner circumferential portion 51 positioned opposite the outer circumferential surface 20a of the rod-shaped member 20, an outer circumferential portion 52 positioned further apart from the outer circumferential surface 20a than the inner circumferential portion 51 in a second direction perpendicular to a first direction along the central axis CL of the rod-shaped member 20, and a heating surface 53 connecting the inner circumferential portion 51 and the outer circumferential portion 52, extending continuously in the circumferential direction centered on the central axis CL. The inner circumferential portion 51 and the outer circumferential portion 52 extend continuously in the circumferential direction centered on the central axis CL. The heating surface 53 is positioned in a plane perpendicular to the first direction along the central axis CL. Continuous means being a single continuous unit over the circumferential direction centered on the central axis CL. The second direction is the radial direction (also called the radial direction) centered on the central axis CL.

[0043] The heating structure 8 includes spacers 55 provided between adjacent heating elements 14 among a plurality of heating elements 14 arranged along a first direction. The spacers 55 are made of a material that has heat resistance and pressure resistance. The spacers 55 form a space between adjacent heating elements 14, preventing contact between adjacent heating elements 14. The spacers 55 position the plurality of heating elements 14 in the first direction.

[0044] The spacer 55 is in contact with the outer circumferential surface 20a of the rod-shaped member 20. The spacer 55 is formed in an annular shape. The rod-shaped member 20 is inserted into the opening formed by the inner edge of the spacer 55. The spacer 55 is fixed to the outer circumferential surface 20a of the rod-shaped member 20 because its inner edge is in contact with the outer circumferential surface 20a of the rod-shaped member 20. In this embodiment, the spacer 55 is formed in an annular shape. However, the spacer 55 is not limited to being an annular shape, and may also be a polygonal annular shape, etc.

[0045] The inner circumference 51 of the heating element 14 is arranged around the entire circumference. The inner circumference 51 forms a through hole in the heating element 14. The inner circumference 51 is located at a position spaced apart in the second direction from the outer surface 20a of the rod-shaped member 20. A gap is formed between the inner circumference 51 of the heating element 14 and the outer surface 20a of the rod-shaped member 20. The diameter of the inner circumference 51 is larger than the diameter of the outer surface 20a of the rod-shaped member 20. The diameter of the inner circumference 51 is the inner diameter of the heating element 14. For example, if the heating element 14 is a polygonal annular shape, the inner diameter of the heating element 14 is the diameter of the inscribed circle of the inner circumference 51.

[0046] The outer periphery 52 is arranged around the entire circumference. The outer periphery 52 is positioned at a distance from the inner surface of the sealed container 5 (the inner surface of the body) in the second direction. A gap is formed between the outer periphery 52 of the heating element 14 and the inner surface of the sealed container 5. The diameter of the outer periphery 52 is smaller than the inner diameter of the sealed container 5. The inner diameter of the sealed container 5 is the diameter of the inner surface of the body. The diameter of the outer periphery 52 is the outer diameter of the heating element 14. For example, if the heating element 14 is a polygonal ring, the outer diameter of the heating element 14 is the diameter of the circumscribed circle of the outer periphery 52.

[0047] The heating surface 53 extends continuously from the inner circumference 51 to the outer circumference 52. That is, the heating surface 53 extends continuously in a second direction perpendicular to the first direction. The heating surface 53 is formed in an annular shape. The heating surface 53 is the surface of the multilayer film 62 (see Figure 3), which will be described later. The amount of heat generated by the heating element 14 increases as the area of ​​the heating surface 53 increases. The amount of heat generated by the heating element 14 is the amount of heat generated when hydrogen atoms permeate through the heterogeneous material interface 73, which will be described later, by quantum diffusion, or when hydrogen atoms diffuse through the heterogeneous material interface 73 by quantum diffusion.

[0048] Eddy currents are generated on the heating surface 53 of the heating element 14 when an alternating current is applied to the induction coil 15. The temperature of the heating surface 53 rises due to the eddy currents. The eddy currents are generated at positions corresponding to the distance from the induction coil 15, depending on the frequency of the alternating current. For example, at a low frequency (60 Hz), the entire heating surface 53 is heated uniformly, while at a high frequency (1 MHz), only 1 mm from the outer edge 52 of the heating surface 53 is partially heated. In this way, the temperature distribution of the entire heating surface 53 of the heating element 14 can be adjusted by changing the frequency of the alternating current applied to the induction coil 15.

[0049] Next, the configuration of the heating element 14 will be described. Figure 3 is a cross-sectional view showing the configuration of the heating element 14. As shown in Figure 3, the heating element 14 has a support 61 (also referred to as a base) made of a hydrogen-absorbing metal, hydrogen-absorbing alloy, or proton conductor, and a multilayer film 62 provided on the support 61. The multilayer film 62 has a first layer 71 less than 1000 nm thick made of a hydrogen-absorbing metal or hydrogen-absorbing alloy, and a second layer 72 less than 1000 nm thick made of a hydrogen-absorbing metal, hydrogen-absorbing alloy, or ceramic different from the first layer 71. A heterogeneous material interface 73 is formed between the first layer 71 and the second layer 72, and between the support 61 and the multilayer film 62. The heterogeneous material interface 73 allows hydrogen atoms to pass through. The heating element 14 generates excess heat when hydrogen atoms pass through the heterogeneous material interface 73 by quantum diffusion, or when hydrogen atoms diffuse through the heterogeneous material interface 73 by quantum diffusion. As the heating element 14, heating elements disclosed in International Publications WO2018 / 230447, WO2020 / 122097, WO2020 / 122098, etc., can be used. The detailed configuration, function, and manufacturing method of the heating element 14 are the same as those disclosed in International Publications WO2018 / 230447, WO2020 / 122097, WO2020 / 122098, etc., and therefore will not be explained here.

[0050] In Figure 3, the multilayer film 62 is shown as being laminated on one side (e.g., the front surface) of the support 61. However, the design is not limited to this configuration. The multilayer film 62 may also be laminated on the other side (e.g., the back surface) of the support 61, or on both sides (the front and back surfaces) of the support 61.

[0051] The operation and effects of the heating device 3 according to this embodiment will now be explained. First, the exhaust valve 13 is opened and the vacuum pump 7 is driven. The space 9 inside the sealed container 5 is evacuated by vacuum. The vacuum pump 7 is stopped, the exhaust valve 13 is closed, and the power supply 19 is driven. An alternating current is applied from the power supply 19 to the induction coil 15 via the conductive wire 18. The induction coil 15 generates eddy currents in the heating element 14 when alternating current is applied. The heating element 14 is heated by the eddy currents. When a low frequency (e.g., 60 Hz) current is applied to the induction coil 15, eddy currents are generated across the entire heating surface 53, the entire heating surface 53 is heated uniformly, and the temperature distribution of the heating element 14 is made uniform. In this way, the temperature of the heating element 14 can be raised uniformly to a specific temperature. For example, by setting the temperature of the heating element 14 to about 200°C, moisture can be removed from the heating element 14.

[0052] Next, the output of the power supply 19 is increased, and the temperature of the heating element 14 rises further. For example, the temperature of the heating element 14 is set to about 300°C. The supply valve 12 is opened, and hydrogen-based gas flows from the hydrogen tank 6 into the space 9 inside the sealed container 5. The space 9 inside the sealed container 5 is filled with hydrogen-based gas. The heating element 14 absorbs hydrogen. Specifically, hydrogen molecules in space 9 are adsorbed onto the surface of the multilayer film 62 of the heating element 14 (the side opposite to the support 61), and these hydrogen molecules dissociate into two hydrogen atoms. Then, the dissociated hydrogen atoms penetrate (absorb) into the interior of the multilayer film 62.

[0053] After hydrogen is absorbed into the heating element 14, the supply valve 12 is closed. The output of the power supply 19 is controlled so that the temperature of the heating element 14 is set to any temperature within the optimal temperature range for heating (for example, around 700°C). At this time, the exhaust valve 13 is opened and the vacuum pump 7 is driven. Hydrogen-based gas is discharged from the space 9 inside the sealed container 5. The heating element 14 releases hydrogen. Specifically, hydrogen atoms that have penetrated into the multilayer film 62 return to the surface of the multilayer film 62, recombine, and are released as hydrogen molecules. As a result, hydrogen atoms permeate the heterogeneous interface 73 by quantum diffusion, or hydrogen atoms diffuse through the heterogeneous interface 73 by quantum diffusion, generating excess heat in the heating element 14. The excess heat from the heating element 14 heats the heat transfer medium passing through the coiled pipe 201. The excess heat recovered by the heat transfer medium is used as thermal energy.

[0054] In the heating device 3 according to this embodiment, the heating element 14 is heated by eddy currents generated when an alternating current is applied to the induction coil 15. Eddy currents are generated at positions corresponding to the frequency of the current applied to the induction coil 15. When a high-frequency current (e.g., 1 MHz) is applied to the induction coil 15, the eddy currents generated near the outer circumference 52 of the heating element 14 become larger, while the eddy currents generated near the inner circumference 51 of the heating element 14 become smaller, compared to when a low-frequency current (e.g., 60 Hz) is applied to the induction coil 15. In other words, as the frequency of the current applied to the induction coil 15 is increased, the area near the outer circumference 52 of the heating element 14 can be heated more intensively. When excess heat is generated in the heating element 14, the temperature near the inner circumference 51 of the heating element 14 tends to be higher than the temperature near the outer circumference 52. By increasing the frequency of the current applied to the induction coil 15, the area near the outer circumference 52 of the heating element 14 can be heated more intensively, and the temperature distribution of the heating element 14 can be made more uniform.

[0055] Figure 4 shows a schematic graph of the temperature distribution and eddy current magnitude of the heating structure 8. Figure 4 shows the temperature and eddy current magnitude from the inner circumference 51 to the outer circumference 52 of the heating element 14. In Figure 4, the horizontal axis represents the radial (radiative) position centered on the central axis CL of the heating element 14, the left vertical axis represents the temperature of the heating element 14, and the right vertical axis represents the magnitude of the eddy current generated in the heating element 14. Figure 4(a) is a graph when the heating device 3 is in operation and a low frequency (e.g., 60 Hz) alternating current is applied to the induction coil 15. Figure 4(b) is a graph when the heating element 14 is generating excess heat and a high frequency (e.g., 1 MHz) alternating current is applied to the induction coil 15. Figure 4(c) is a graph when the heating element 14 is generating excess heat and no alternating current is applied to the induction coil 15. The "heating element failure temperature" is the temperature at which the heating element 14 fails, and the "deactivation temperature" is the temperature at which the heating element 14 stops generating excess heat.

[0056] When a low-frequency (e.g., 60 Hz) alternating current is applied to the induction coil 15 (Figure 4(a)), the magnitude of the eddy currents generated in the heating element 14 increases from the inner circumference 51 to the outer circumference 52. The temperature of the heating element 14 decreases from the inner circumference 51 to the outer circumference 52. This is because heat is more easily released from the outer circumference 52.

[0057] When a high-frequency (e.g., 1 MHz) alternating current is applied to the induction coil 15 (Figure 4(b)), the eddy currents in the inner circumference 51 are smaller than when a low-frequency alternating current is applied to the induction coil 15, and the eddy currents in the outer circumference 52 are larger than when a low-frequency alternating current is applied to the induction coil 15. In other words, when a high-frequency alternating current is applied to the induction coil 15, the difference between the magnitude of the eddy currents in the inner circumference 51 and the magnitude of the eddy currents in the outer circumference 52 is larger than when a low-frequency alternating current is applied to the induction coil 15. This is because the higher the frequency of the alternating current applied to the induction coil 15, the larger the eddy currents become closer to the induction coil 15, that is, closer to the outer circumference 52 of the heating element 14.

[0058] As shown in Figure 4(c), when excess heat is generated in the heating element 14 without applying an alternating current to the induction coil 15, the temperature difference between the inner circumference 51 and the outer circumference 52 of the heating element 14 is larger compared to when excess heat is generated in the heating element 14 while applying an alternating current to the induction coil 15 (Figure 4(b)). This is because, when excess heat is generated in the heating element 14 without applying an alternating current to the induction coil 15 (Figure 4(c)), the heating element 14 only releases excess heat, whereas when excess heat is generated in the heating element 14 while applying an alternating current to the induction coil 15 (Figure 4(b)), the heating element 14 not only releases excess heat but is also heated by eddy currents. Since excess heat is more easily released from the outer circumference 52 than from the inner circumference 51, and a high-frequency alternating current is applied to the induction coil 15, larger eddy currents are generated in the outer circumference 52 than in the inner circumference 51, causing the outer circumference 52 to heat up more than the inner circumference 51. Therefore, the temperature difference between the inner and outer circumferences of the heating element 14 can be reduced, and the temperature distribution of the heating element 14 can be made uniform.

[0059] The heating structure 8 has multiple heating elements 14 arranged along a first direction, which increases the total area obtained by adding the areas of each heating surface 53, and thus increases the amount of heat generated. The heating structure 8 can easily increase the total area of ​​the heating surface 53 simply by increasing the number of heating elements 14. The heating structure 8 can easily increase or decrease the amount of heat generated by changing the number of heating elements 14.

[0060] The heating structure 8 includes spacers 55 provided between adjacent heating elements 14 among a plurality of heating elements 14 arranged along a first direction, thereby creating a space between adjacent heating elements 14 and preventing contact between them. This suppresses a decrease in heat generation due to contact between the heating surfaces 53 of the heating elements 14 and prevents the heating elements 14 from fusing together due to thermal diffusion of the metal. Each heating element 14 is efficiently heated by radiant heat from adjacent heating elements 14, making it possible to reach the optimal temperature for heating in a shorter time.

[0061] The operation and effects of the heat utilization system 1 according to this embodiment will now be explained. In the piping path 2, helium gas, which serves as a heat transfer medium, flows into the coiled pipe 201 by the pressure pump 43. In the coiled pipe 201, heat is transferred from the heat generating device 3 to the helium gas, and the temperature of the helium gas rises. The high-temperature helium gas that flows out of the coiled pipe 201 flows into the compressor (not shown) of the power generation unit 42. The high-temperature and high-pressure helium gas that flows out of the compressor flows into the gas turbine 42a, which rotates the turbine blades of the gas turbine 42a. The rotation of the turbine blades is transmitted to the rotor of the generator 42b. Electricity is generated by the generator 42b.

[0062] The thermal energy of the helium gas is consumed to rotate the turbine blades of the gas turbine 42a. As the temperature of the helium gas decreases in the gas turbine 42a, the pressure also decreases. The helium gas that flows out of the gas turbine 42a is drawn into the pressure pump 43. The helium gas is then sent from the pressure pump 43 towards the coiled piping 201. Power generation continues in accordance with the circulation of the helium gas.

[0063] As described above, the heat utilization system 1 uses a heat transfer medium heated by a heat generating device 3 equipped with a heat generating element 14 that generates heat by the absorption and release of hydrogen as a heat source, thus enabling the supply of energy inexpensively, cleanly, and safely.

[0064] In the heat utilization system 1, the coiled piping 201 is formed by winding a portion of the piping path 2 around the sealed container 5, which allows the heat transfer medium flowing through the coiled piping 201 to be efficiently heated by the heating element 14.

[0065] (2) Heating device and heat utilization system according to the second embodiment In the first embodiment described above, the induction coil 15 is formed from a linear conductive member installed inside the coiled pipe 201, but in the second embodiment, the induction coil 15a is formed from the pipe. In other words, in the second embodiment, the coiled pipe 201 itself from the first embodiment is used as the induction coil.

[0066] Figure 5 is a conceptual diagram schematically showing the configuration of the heat utilization system 1a according to the second embodiment. In the heat generating device 3a of the heat utilization system 1a, the conductive member forming the induction coil 15a is a pipe through which the heat transfer medium for heat exchange passes, and is electrically insulated.

[0067] One end of the induction coil 15a is connected to a pressure pump 43, and a heat transfer medium is supplied from the pressure pump 43 to the induction coil 15a. The heat transfer medium that flows into the induction coil 15a is heated by a heating structure 8 housed in a sealed container 5. The temperature of the heat transfer medium rises inside the induction coil 15a, and a high-temperature heat transfer medium is obtained.

[0068] The other end of the induction coil 15a is connected to the power generation unit 42. The heat transfer fluid heated inside the induction coil 15a flows into the power generation unit 42. The thermal energy of the heat transfer fluid is consumed by the rotation of the turbine blades of the gas turbine 42a. As the temperature of the heat transfer fluid decreases in the gas turbine 42a, the pressure also decreases. The heat transfer fluid that flows out of the gas turbine 42a is drawn into the pressure pump 43. The heat transfer fluid is then sent from the pressure pump 43 back to the induction coil 15a. Power generation continues in accordance with the circulation of the heat transfer fluid.

[0069] The induction coil 15a is connected to a conductive wire 18. The conductive wire 18 is connected to a power supply 19, electrically connecting the induction coil 15a and the power supply 19. When current is applied to the induction coil 15a from the power supply 19 via the conductive wire 18, eddy currents are generated in the heating element 14. The induction coil 15a heats the heating element 14 with these eddy currents.

[0070] In the heating device 3a according to the second embodiment, the linear conductive member forming the induction coil 15a is a pipe, and a heat exchange medium flows through the pipe. The heating element 14 is heated by eddy currents generated when an alternating current is applied to the induction coil 15a. The eddy currents are generated at positions corresponding to the frequency of the current applied to the induction coil 15a. When a high-frequency current (e.g., 1 MHz) is applied to the induction coil 15a, the eddy currents generated near the outer circumference 52 of the heating element 14 become larger, while the eddy currents generated near the inner circumference 51 of the heating element 14 become smaller, compared to when a low-frequency current (e.g., 60 Hz) is applied to the induction coil 15a. In other words, as the frequency of the current applied to the induction coil 15a is increased, the area near the outer circumference 52 of the heating element 14 can be heated more intensively. When excess heat is generated in the heating element 14, the temperature near the inner circumference 51 of the heating element 14 tends to be higher than the temperature near the outer circumference 52. By increasing the frequency of the current applied to the induction coil 15a, the area near the outer circumference 52 of the heating element 14 can be heated more intensely, thereby making the temperature distribution of the heating element 14 more uniform.

[0071] (3) Heating device according to the third embodiment In the first and second embodiments, the heating element 14 is formed in an annular shape, but in the third embodiment, the shape of the heating element is different.

[0072] Figure 6 is an exploded perspective view of the heat-generating structure 8b according to the third embodiment. The heat-generating structure 8b comprises a heat-generating element 14b, an upper fixing part 32, a lower fixing part 33, and a guide 34. The heat-generating element 14b is formed by winding a plate-shaped member made of a multilayer film 62 that generates heat through the absorption and release of hydrogen. Hereinafter, the winding axis of the heat-generating element 14b will also be referred to as the "central axis CL". The heat-generating element 14b is held by the guide 34, which is positioned near the middle of the direction along the central axis CL, and its ends in the direction along the central axis CL (up and down direction) are fixed by the upper fixing part 32 and the lower fixing part 33.

[0073] In detail, the heating element 14b is constructed by winding a plate-shaped member (three times in this figure). The upper fixing part 32 is a disc-shaped member with an opening in the center and has a spiral groove 322 on its lower end face. The lower fixing part 33 is a disc-shaped member with an opening in the center and has a spiral groove 332 on its upper end. The upper fixing part 32 and the lower fixing part 33 (fixing part) are configured as a pair. The guide 34 is a disc-shaped member with an opening in the center and has a spiral through groove 342 that penetrates in the axial direction. The rod-shaped member 20 (see Figure 2) is inserted through the openings of the upper fixing part 32, the lower fixing part 33, and the guide 34.

[0074] The groove 322 of the upper fixing portion 32 has a groove width that is slightly larger than the thickness of the plate-shaped member forming the heating element 14b. The groove length along the spiral direction is longer than the winding length of the heating element 14b, and at the outermost circumference, it extends toward the outer circumference of the upper fixing portion 32 and is configured to penetrate the outer surface.

[0075] The groove 332 of the lower fixing part 33 and the through groove 342 of the guide 34 have the same spiral structure as the groove 322 of the upper fixing part 32. Due to this configuration, when the heating structure 8b is assembled, the upper end of the heating element 14b is housed in the groove 322 of the upper fixing part 32, and the lower end of the heating element 14b is housed in the groove 332 of the lower fixing part 33. The middle portion of the heating element 14b along the central axis CL is then fixed by the through groove 342 of the guide 34. Since the groove lengths of grooves 322, 332, and the through groove 342 are longer than the winding length of the heating element 14b, the occurrence of distortion due to thermal expansion when the heating element 14b is heated can be suppressed. In addition, the groove of the through groove 342 is the same size (groove width and groove length) as the groove 322 of the upper fixing part 32 and the groove 332 of the lower fixing part 33.

[0076] In this disclosure, "equal" and "same" do not only mean "exactly equal" and "exactly the same," but also include "approximately equal" and "approximately the same," meaning that an error of, for example, a few percent may be included. By making the groove width and groove length of grooves 322, 332, and through groove 342 approximately the same, contact with the rod-shaped member 20 due to deflection of the heating element 14b, and contact between adjacent winding surfaces of the heating element 14b can be prevented.

[0077] The upper fixing portion 32, the lower fixing portion 33, and the guide 34 are formed from a non-metallic material, such as ceramics. This prevents adhesion in the grooves 322, 332, and through groove 342 when the heating element 14b generates heat.

[0078] The induction coil 15 (see Figure 1) is formed by winding a linear conductive member around the central axis CL of the heating element 14b on the outer circumference of the sealed container 5. When an alternating current is applied to the induction coil 15, eddy currents are generated in the heating element 14b, causing it to heat up. The eddy currents are generated at locations corresponding to the frequency of the current applied to the induction coil 15. When a high-frequency current (e.g., 1 MHz) is applied to the induction coil 15, the eddy currents generated near the outer circumference of the heating element 14b become larger, while the eddy currents generated near the inner circumference of the heating element 14b become smaller, compared to when a low-frequency current (e.g., 60 Hz) is applied to the induction coil 15. In other words, as the frequency of the current applied to the induction coil 15 increases, the area near the outer circumference of the heating element 14b can be heated more intensively. When excess heat is generated in the heating element 14b, the temperature near the inner circumference of the heating element 14b tends to be higher than the temperature near the outer circumference. By increasing the frequency of the current applied to the induction coil 15, the area near the outer circumference of the heating element 14b can be heated more intensely, thereby making the temperature distribution of the heating element 14b more uniform.

[0079] (4) Heating device and heat utilization system according to the fourth embodiment In the first embodiment, the heat transfer medium is heated only in the coiled piping 201 wound around the sealed container 5 by the excess heat of the heating elements 14 and 14b, whereas in the fourth embodiment, the heat transfer medium can flow through the rod-shaped member 20 and is also heated in the induction coil 15a by the excess heat of the heating elements 14 and 14b.

[0080] Figure 7 is a conceptual diagram schematically showing the configuration of the heat utilization system 1c according to the fourth embodiment. In the heat utilization system 1c, the piping route 2c includes an inner piping 202 provided in parallel with the coiled piping 201. The inner piping 202 is formed by a cylindrical rod-shaped member 20 and is provided inside the heating element 14. The rod-shaped member 20 is appropriately designed based on the temperature and pressure of the heat transfer medium flowing through it.

[0081] When the heat-generating element 14 is generating excess heat, the heat transfer medium is circulated through the inner piping 202, and the heat transfer medium is heated by the excess heat from the heat-generating element 14. This results in a high-temperature heat transfer medium. The high-temperature heat transfer medium flows out of the inner piping 202 and into the power generation unit 42.

[0082] In the heating device 3c, excess heat from the heating element 14 is recovered by a heat transfer medium flowing through the inner piping 202. In other words, the heating element 14 is cooled from the inner circumference 51 by the heat transfer medium flowing through the inner piping 202. Therefore, the temperature of the inner circumference 51 of the heating element 14, which tends to become hotter than the outer circumference 52, can be reduced, and the temperature distribution of the heating element 14 can be made more uniform.

[0083] In the fourth embodiment, the induction coil 15 is provided inside the coiled pipe 201, but it may also be configured to include an induction coil 15a formed from the pipe, similar to the second embodiment. Furthermore, in the fourth embodiment, a ring-shaped heating element 14 is used, but it may also be configured to include a heating element 14b formed by winding, similar to the third embodiment. Moreover, in the fourth embodiment, the piping route 2c includes both the coiled pipe 201 and the inner pipe 202, but it may also include only the inner pipe 202 and not the coiled pipe 201. Even if the piping route 2c does not include the coiled pipe 201, the induction coil 15 is formed by winding around the sealed container 5.

[0084] The present invention is not limited to the embodiments described above, and can be modified as appropriate without departing from the spirit of the invention.

[0085] The heating element 14 may have a shape in which multiple plate-shaped members, each composed of a multilayer film 62, are stacked in a direction perpendicular to the central axis of the rod-shaped member 20 (see Figure 2). In other words, the present invention can be applied regardless of the shape of the heating element 14, and can be applied when the heating element 14 has an inner circumference and an outer circumference. [Explanation of symbols]

[0086] 3, 3a, 3c heating device 5. Airtight container 10 Introductory tube 11 Exhaust pipe 14, 14b Heating element 15, 15a Induction coil 19 Power supply 201 Coiled piping 202 Internal piping CL center axis

Claims

1. A heating element formed by a plate-shaped member made of a multilayer film that generates heat through the absorption and release of hydrogen, which is arranged in a ring shape or wound around it, A sealed container for housing the heating element, An introduction line for introducing a gas containing hydrogen into the aforementioned sealed container, A discharge line for dischargeing the gas that has been used to generate heat in the heating element by the absorption and release of hydrogen in the heating element, An induction coil is formed by winding a linear conductive member around the central axis of the heating element on the outer circumference of the sealed container, The system comprises a power supply for applying alternating current to the induction coil, The power supply is capable of changing the frequency of the alternating current. The sealed container is further equipped with piping that is wound around the central axis of the heating element on its outer circumference and through which a heat transfer medium for heat exchange passes, The induction coil is provided inside the piping. Heating device.

2. A heating element formed by a plate-shaped member made of a multilayer film that generates heat through the absorption and release of hydrogen, which is arranged in a ring shape or wound around it, A sealed container for housing the heating element, An introduction line for introducing a gas containing hydrogen into the aforementioned sealed container, A discharge line for dischargeing the gas that has been used to generate heat in the heating element by the absorption and release of hydrogen in the heating element, An induction coil is formed by winding a linear conductive member around the central axis of the heating element on the outer circumference of the sealed container, The system comprises a power supply for applying alternating current to the induction coil, The power supply is capable of changing the frequency of the alternating current. The aforementioned conductive member is a pipe through which a heat transfer medium for heat exchange passes. Heating device.

3. A heating element formed by a plate-shaped member made of a multilayer film that generates heat through hydrogen absorption and release, which is arranged in an annular shape or wound around it, A sealed container for housing the heating element, An introduction line for introducing a gas containing hydrogen into the aforementioned sealed container, A discharge line for dischargeing the gas that has been used to generate heat in the heating element by the absorption and release of hydrogen in the heating element, An induction coil is formed by winding a linear conductive member around the central axis of the heating element on the outer circumference of the sealed container, The system comprises a power supply for applying alternating current to the induction coil, The power supply is capable of changing the frequency of the alternating current. The heating element is further provided with piping through which a heat exchange medium passes, located inside the heating element. Heating device.

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