System

Abstract

To provide technology to use hydrogen absorbing alloys for unconventional applications.SOLUTION: The system comprises a boiler and a vessel containing a hydrogen absorbing alloy. The vessel is configured to be heated directly or indirectly by the fluid released from the boiler.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a system using a hydrogen storage alloy.

Background Art

[0002] Since carbon dioxide is not generated during the combustion of hydrogen, hydrogen is expected as a green energy. As something that can supply hydrogen as fuel, there is a hydrogen storage alloy. A hydrogen storage alloy is a material that can store hydrogen. The hydrogen storage alloy releases the stored hydrogen when heated.

[0003] Regarding this, Japanese Unexamined Patent Application Publication No. 2009-264216 (Patent Document 1) discloses a heating system using a hydrogen storage alloy. The purpose of the heating system is to improve the energy conversion efficiency by heating the hydrogen storage alloy with the waste heat of the engine.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] The heating system disclosed in Patent Document 1 heats the hydrogen storage alloy with the waste heat of the engine and assumes the use of the hydrogen storage alloy in the engine. In addition to this, the uses of hydrogen storage alloys are being explored.

[0006] The present invention has been made to solve such problems, and its object is to use a hydrogen storage alloy for an unprecedented use.

Means for Solving the Problems

[0007] In an example of the present disclosure, a system is provided. The system includes a boiler and a container containing a hydrogen storage alloy. The container is configured to be directly or indirectly heated by a fluid discharged from the boiler.

[0008] In an example of the present disclosure, the container is configured to be able to heat the hydrogen storage alloy by heat exchange with a heat medium. The heat medium is heated by the fluid.

[0009] In an example of the present disclosure, the boiler is a hydrogen combustion boiler that uses hydrogen as fuel. The hydrogen combustion boiler is configured to use hydrogen released from the hydrogen storage alloy as fuel when the fluid heats the heat medium.

[0010] In an example of the present disclosure, the boiler further uses combustible gas as fuel. The system further includes a control unit and a switching mechanism capable of switching whether to supply combustible gas to the boiler. When a condition indicating that the amount of hydrogen released from the hydrogen storage alloy is not less than a predetermined amount is not satisfied, the control unit executes a process of controlling the switching mechanism so that the combustible gas is supplied to the boiler, and when the condition is satisfied, executes a process of controlling the switching mechanism so that the combustible gas is not supplied to the boiler.

[0011] In an example of the present disclosure, the system further includes a control unit and a heater for heating the container or the heat medium. When a condition indicating that the amount of hydrogen released from the hydrogen storage alloy is not less than a predetermined amount is not satisfied, the control unit executes a process of driving the heater, and when the condition is satisfied, executes a process of stopping the driving of the heater.

[0012] In one example of the present disclosure, the system further includes a control unit, a plurality of the containers, a first switching mechanism capable of switching whether to supply the heat medium to a first container among the plurality of the containers, and a second switching mechanism capable of switching whether to supply the heat medium to a second container among the plurality of the containers. The control unit controls the first switching mechanism to supply the heat medium to the first container and controls the second switching mechanism to stop the supply of the heat medium to the second container, and when the amount of hydrogen released from the hydrogen storage alloy in the first container becomes equal to or less than a predetermined amount, controls the second switching mechanism to supply the heat medium to the second container, and when the amount of hydrogen released from the hydrogen storage alloy in the second container becomes greater than the predetermined amount, controls the first switching mechanism to stop the supply of the heat medium to the first container.

[0013] In one example of the present disclosure, the fluid is the exhaust gas of the boiler or the feed water heated by the boiler.

[0014] In one example of the present disclosure, the hydrogen storage alloy is heated to 10°C or higher and 60°C or lower by the fluid.

[0015] The above and other objects, features, aspects and advantages of the present invention will become apparent from the following detailed description of the present invention understood in connection with the accompanying drawings.

Brief Description of the Drawings

[0016]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Figure 15

Embodiments for Carrying Out the Invention

[0017] Hereinafter, each embodiment according to the present invention will be described with reference to the drawings. In the following description, the same parts and components are denoted by the same reference numerals. Their names and functions are also the same. Therefore, detailed descriptions thereof will not be repeated. Note that each of the embodiments and each modification example described below may be selectively combined as appropriate.

[0018] <A. Overview of Hydrogen Utilization System 100> First, with reference to FIG. 1, the hydrogen utilization system 100 will be described. FIG. 1 is a diagram showing an example of the configuration of the hydrogen utilization system 100.

[0019] As shown in FIG. 1, the hydrogen utilization system 100 includes a boiler 200, a heat exchanger 250, a container 300, and pipes F1, F2A, and F2B.

[0020] The boiler 200 releases a heated fluid by burning fuel. The "fluid" here means at least one of a gas, a liquid, or a mixture of a gas and a liquid. As an example, the fluid may be the exhaust gas of the boiler 200 generated during fuel combustion, may be the feed water heated by burning fuel, or may be the unheated feed water from the boiler 200. The fluid released from the boiler 200 is sent to the heat exchanger 250 through the pipe F1.

[0021] The pipe F1 may be configured to be able to guide the fluid heated by the boiler 200 from the boiler 200 to the heat exchanger 250, and may be composed of a single pipe or a plurality of pipes.

[0022] The heat exchanger 250 performs heat exchange between the fluid sent from the boiler 200 and the heat medium flowing through the pipes F2A and F2B, and heats the heat medium. The heat medium is a fluid and may be, for example, a gas or a liquid such as antifreeze or water. The heat medium flows repeatedly through the pipe F2A, the heat exchanger 250, the pipe F2B, and the container 300 in sequence.

[0023] The type of the heat exchanger 250 is not particularly limited. As an example, the heat exchanger 250 is a multi-tube heat exchanger. Alternatively, the heat exchanger 250 may be a plate heat exchanger. Alternatively, the heat exchanger 250 may be a finned tube heat exchanger.

[0024] The pipe F2A may be configured to be able to guide the heat medium from the heat exchanger 250 to the container 300, and may be composed of a single pipe or a plurality of pipes. Similarly, the pipe F2B may be configured to be able to guide the heat medium from the container 300 to the heat exchanger 250, and may be composed of a single pipe or a plurality of pipes.

[0025] The container 300 is configured to be able to accommodate the hydrogen storage alloy 350. The hydrogen storage alloy 350 is a material that can absorb hydrogen under a predetermined temperature and a predetermined pressure. In the hydrogen utilization system 100, a container 300 in which hydrogen is stored is set. The hydrogen storage alloy releases the absorbed hydrogen when heated. The hydrogen storage alloy releases hydrogen when heated to, for example, 10°C or higher. Note that the higher the temperature of the hydrogen storage alloy, the greater the amount of hydrogen released per unit time from the hydrogen storage alloy.

[0026] Also, the container 300 is configured to be directly or indirectly heated by a fluid heated by the boiler 200. That is, the fluid may directly heat the container 300 without any intervening object, or may indirectly heat the container 300 through some object. In the example of FIG. 1, the fluid indirectly transfers heat to the container 300 by heat exchange with the heat medium. In this way, by heating the container 300 through the heat medium, the heat exchange efficiency is increased. Note that when the fluid directly heats the container 300, the hydrogen utilization system 100 does not need to include the heat exchanger 250 and the heat medium.

[0027] When the container 300 is heated, heat is transferred to the hydrogen storage alloy 350 accommodated in the container 300. Thereby, the hydrogen storage alloy 350 is heated and hydrogen is released from the hydrogen storage alloy 350. As an example, the hydrogen storage alloy 350 is heated to 10°C or higher and 60°C or lower. Preferably, the hydrogen storage alloy 350 is heated to 30°C or higher and 60°C or lower.

[0028] As described above, in the hydrogen utilization system 100 according to the present embodiment, the heat generated by the boiler 200 is used for heating the hydrogen storage alloy 350. Thereby, the waste heat of the boiler 200 is efficiently utilized and the energy efficiency is improved. The use of the hydrogen storage alloy 350 for the boiler 200 is not conventional, and it can contribute to the spread of the hydrogen storage alloy 350.

[0029] In addition, as another means of supplying hydrogen, there is a hydrogen-filled cylinder. However, when filling hydrogen into a commonly used high-pressure hydrogen cylinder, since hydrogen is compressed to 1 MPaG or higher, the High-Pressure Gas Safety Act is applied. That is, qualifications are required when handling hydrogen cylinders. Also, the cost of equipment increases. In particular, in areas with a small population, it is difficult to secure qualified personnel, and the hurdle for introducing hydrogen cylinders is very high.

[0030] On the other hand, the hydrogen storage alloy 350 can absorb hydrogen at a pressure of less than 1 MPaG and can reversibly absorb and release hydrogen. Therefore, when handling the hydrogen storage alloy 350, it is not necessary to secure qualified personnel. Thus, the hydrogen storage alloy 350 can be easily introduced even in areas where it is difficult to secure qualified personnel.

[0031] Also, since the boiler 200 exists in any area, the hurdle for introducing the hydrogen utilization system 100 combining the boiler 200 and the hydrogen storage alloy 350 is very low. As a result, the utilization of hydrogen, which is a green energy, can be promoted, contributing to the improvement of the environment.

[0032] <B. Usage form of the hydrogen utilization system 100> Next, with reference to FIG. 2, the usage form of the hydrogen utilization system 100 shown in FIG. 1 will be described. FIG. 2 is a diagram for explaining an example of the usage form of the hydrogen utilization system 100.

[0033] In the hydrogen utilization system 100 shown in FIG. 2, the boiler 200 is a hydrogen combustion boiler that uses hydrogen as fuel. And the boiler 200, which is a hydrogen combustion boiler, is configured to use the hydrogen released from the hydrogen storage alloy 350 as fuel by heating the heat medium in the container 300.

[0034] More specifically, the hydrogen utilization system 100 shown in FIG. 2 is different from the hydrogen utilization system 100 shown in FIG. 1 in that it includes a pipe F3. The pipe F3 is configured to connect the boiler 200 and the container 300. Note that the pipe F3 may be configured to be able to guide the hydrogen released from the hydrogen storage alloy 350 to the boiler 200, and may be composed of a single pipe or a plurality of pipes.

[0035] As described above, in the hydrogen utilization system 100 shown in FIG. 2, the heat transfer from the boiler 200 to the container 300 and the supply of hydrogen from the container 300 to the boiler 200 are repeatedly performed in parallel. As a result, the energy conversion efficiency is improved.

[0036] In addition, when the boiler 200 burns hydrogen, no carbon dioxide gas is generated. Therefore, the hydrogen utilization system 100 can also contribute to environmental improvement.

[0037] Furthermore, the use of the hydrogen storage alloy 350 in a hydrogen combustion boiler such as the boiler 200 is unprecedented, and can contribute to the popularization of the hydrogen storage alloy 350 and the hydrogen combustion boiler.

[0038] <C. Container 300> Next, with reference to FIG. 3, the configuration of the above-described container 300 will be described. FIG. 3 is a view showing the external appearance of the container 300.

[0039] As shown in FIG. 3, the container 300 includes a main body 310, an inlet 315A, an outlet 315B, a discharge port 320, and a valve 325.

[0040] The main body 310 has, for example, a cylindrical shape. In addition, the inside of the main body 310 is partitioned into an inner space for housing the above-described hydrogen storage alloy 350 and an outer space through which the above-described heat medium passes.

[0041] Typically, the main body 310 is composed of an outer cylindrical surface forming the outer surface of the main body 310 and an inner cylindrical surface having a smaller diameter than the outer cylindrical surface. The inner space is the space inside the inner cylindrical surface. The outer space is the space between the outer cylindrical surface and the inner cylindrical surface. The inner cylindrical surface and the outer cylindrical surface are supported by both side surfaces of the main body 310, for example.

[0042] The outer space of the main body 310 is spatially connected to the inlet 315A and the outlet 315B. The inlet 315A is connected to the above-described pipe F2A (see FIG. 2). The outlet 315B is connected to the above-described pipe F2B (see FIG. 2).

[0043] The above-described heat medium (see FIG. 2) flows into the outer space of the main body 310 from the inlet 315A, flows through the outer space, and flows out from the outlet 315B. At this time, the heat medium exchanges heat with the hydrogen storage alloy 350 stored in the inner space of the main body 310 and heats the hydrogen storage alloy 350.

[0044] Preferably, the main body 310 is configured such that the heat medium flows spirally in the outer space of the main body 310. Thereby, the heat exchange efficiency between the heat medium and the hydrogen storage alloy 350 is improved.

[0045] The inner space of the main body 310 is spatially connected to the discharge port 320. Further, the discharge port 320 is connected to the above-described pipe F3 (see FIG. 2). The hydrogen generated by heating the hydrogen storage alloy 350 is discharged from the discharge port 320 and sent to the boiler 200 via the pipe F3.

[0046] The valve 325 is configured to be able to switch the open / closed state between at least two states of an open state and a closed state. When the valve 325 is in the open state, the hydrogen generated by heating the hydrogen storage alloy 350 is discharged from the discharge port 320. On the other hand, when the valve 325 is in the closed state, the discharge of hydrogen from the discharge port 320 stops.

[0047] Note that the opening and closing of the valve 325 may be manually performed or may be automatically performed by control. Also, the opening degree of the valve 325 may be adjustable or may be constant.

[0048] <D. Control of Hydrogen Utilization System 100> Next, with reference to FIG. 4, the control of the hydrogen utilization system 100 will be described. FIG. 4 is a diagram showing an example of the configuration of the hydrogen utilization system 100.

[0049] When the hydrogen utilization system 100 is started up or the like, the hydrogen storage alloy 350 may not be sufficiently heated. In this case, hydrogen is not sufficiently supplied from the container 300 to the boiler 200. Therefore, when the hydrogen utilization system 100 is started up or the like, it is necessary to heat the container 300 by some means.

[0050] Therefore, the boiler 200 is configured to be able to use a combustible gas as fuel in addition to hydrogen. And the hydrogen utilization system 100 supplies the combustible gas to the boiler 200 before hydrogen is sufficiently supplied to the boiler 200. Thereby, the boiler 200 can use the combustible gas as fuel. As a result, the fluid heated by the boiler 200 warms the container 300 via the heat medium. And the hydrogen utilization system 100 stops the supply of the combustible gas based on the fact that hydrogen is sufficiently supplied from the hydrogen storage alloy 350 to the boiler 200. Thereafter, hydrogen is stably supplied to the boiler 200.

[0051] More specifically, the hydrogen utilization system 100 shown in FIG. 4 is different from the hydrogen utilization system 100 shown in FIG. 2 in that it includes a pipe F4, a control unit 50, a valve 240, and a sensor 245.

[0052] The pipe F4 branches off from the pipe F3 and functions as a supply line for the combustible gas. In the example of FIG. 4, the pipe F4 branches off from the pipe F3 at the branch point P1. Note that the pipe F4 may have a configuration that enables it to guide the combustible gas to the boiler 200, and it may be composed of a single pipe or a plurality of pipes.

[0053] The combustible gas supplied from the pipe F4 to the boiler 200 is, for example, LP (Liquefied Petroleum) gas. The said combustible gas is supplied from, for example, cylinders or the like. Note that the supplied combustible gas does not necessarily have to be high-pressure gas and may be low-pressure gas.

[0054] A valve 240 is provided in the pipe F4. The valve 240 is a switching mechanism capable of switching whether or not to supply the combustible gas to the boiler 200. The valve 240 is configured to be able to switch its open / closed state between at least two states: an open state and a closed state. The opening degree of the valve 240 may be adjustable or may be constant.

[0055] When the valve 240 is in the open state, the combustible gas is supplied to the boiler 200. On the other hand, when the valve 240 is in the closed state, the combustible gas is not supplied to the boiler 200.

[0056] The opening and closing of the valve 240 are controlled by the control unit 50. When a condition (hereinafter, also referred to as the "sufficient heating condition") indicating that the amount of hydrogen released from the hydrogen storage alloy 350 is equal to or more than a predetermined amount is not satisfied, the control unit 50 opens the valve 240 so that the combustible gas is supplied to the boiler 200. On the other hand, when the sufficient heating condition is satisfied, the control unit 50 closes the valve 240 so that the combustible gas is not supplied to the boiler 200.

[0057] Whether or not the sufficient heating condition is satisfied is determined by various methods. Hereinafter, specific examples of the determination method will be described.

[0058] As an example, the control unit 50 determines whether or not the above-described sufficient heating condition is satisfied based on the detection value of the sensor 245. The sensor 245 is provided in the pipe F1. The sensor 245 is, for example, a temperature sensor and detects the temperature of the fluid discharged from the boiler 200. In this example, the above-described sufficient heating condition is satisfied when the temperature of the fluid detected by the sensor 245 is equal to or higher than a predetermined value (for example, 100°C or higher).

[0059] More specifically, when the temperature of the fluid detected by the sensor 245 is lower than the predetermined value, the control unit 50 determines that the above-described sufficient heating condition is not satisfied. In this case, the control unit 50 opens the valve 240. As a result, the combustible gas is supplied to the boiler 200.

[0060] On the other hand, when the temperature of the fluid detected by the sensor 245 is equal to or higher than the predetermined value, the control unit 50 determines that the above-described sufficient heating condition is satisfied. In this case, the control unit 50 closes the valve 240. As a result, the supply of the combustible gas to the boiler 200 stops. Instead, the hydrogen released from the hydrogen storage alloy 350 is supplied to the boiler 200.

[0061] Note that the sensor 245 does not necessarily have to be a temperature sensor. As another example, the sensor 245 may be a flow rate sensor. In this case, the sensor 245 detects the flow rate of the fluid discharged from the boiler 200. In this example, the above-described sufficient heating condition is satisfied when the flow rate detected by the sensor 245 is equal to or higher than a predetermined value.

[0062] More specifically, when the flow rate of the fluid detected by the sensor 245 is lower than the predetermined value, the control unit 50 determines that the above-described sufficient heating condition is not satisfied. In this case, the control unit 50 opens the valve 240. As a result, the combustible gas is supplied to the boiler 200.

[0063] On the other hand, when the flow rate of the fluid detected by the sensor 245 is equal to or greater than a predetermined value, the control unit 50 determines that the above-described sufficient heating condition is satisfied. In this case, the control unit 50 closes the valve 240. As a result, the supply of the combustible gas to the boiler 200 stops. Instead, the hydrogen released from the hydrogen storage alloy 350 is supplied to the boiler 200.

[0064] FIG. 5 is a diagram for explaining another example regarding the method of determining whether or not the above-described sufficient heating condition is satisfied.

[0065] The hydrogen utilization system 100 shown in FIG. 5 is different from the hydrogen utilization system 100 shown in FIG. 4 in that it includes a pressure sensor 246 instead of the sensor 245. The pressure sensor 246 is provided in the pipe F3. As a result, the pressure sensor 246 measures the pressure (atmospheric pressure) in the pipe F3 through which the hydrogen released from the hydrogen storage alloy 350 passes. In this example, the above-described sufficient heating condition is satisfied when the pressure detected by the pressure sensor 246 is equal to or greater than a predetermined value.

[0066] More specifically, when the pressure detected by the pressure sensor 246 is lower than a predetermined value, the control unit 50 determines that the above-described sufficient heating condition is not satisfied. In this case, the control unit 50 opens the valve 240. As a result, the combustible gas is supplied to the boiler 200.

[0067] On the other hand, when the pressure detected by the pressure sensor 246 is equal to or greater than a predetermined value, the control unit 50 determines that the above-described sufficient heating condition is satisfied. In this case, the control unit 50 closes the valve 240. As a result, the supply of the combustible gas to the boiler 200 stops. Instead, the hydrogen released from the hydrogen storage alloy 350 is supplied to the boiler 200.

[0068] FIG. 6 is a diagram for explaining still another example regarding the method of determining whether or not the above-described sufficient heating condition is satisfied.

[0069] In the hydrogen utilization system 100 shown in FIG. 6, it is different from the hydrogen utilization system 100 shown in FIG. 4 in that a temperature sensor 247 is provided instead of the sensor 245. The temperature sensor 247 is provided at any location where the temperature of the hydrogen storage alloy 350 can be directly or indirectly detected. As an example, the temperature sensor 247 may be provided on the surface of the container 300 or inside the container 300. In this example, the above-mentioned sufficient heating condition is satisfied when the temperature detected by the temperature sensor 247 is equal to or higher than a predetermined value.

[0070] More specifically, when the temperature detected by the temperature sensor 247 is lower than a predetermined value, the control unit 50 determines that the above-mentioned sufficient heating condition is not satisfied. In this case, the control unit 50 opens the valve 240. Thereby, the combustible gas is supplied to the boiler 200.

[0071] On the other hand, when the temperature detected by the temperature sensor 247 is equal to or higher than a predetermined value, the control unit 50 determines that the above-mentioned sufficient heating condition is satisfied. In this case, the control unit 50 closes the valve 240. Thereby, the supply of the combustible gas to the boiler 200 stops. Instead, the hydrogen released from the hydrogen storage alloy 350 is supplied to the boiler 200.

[0072] <E. Hardware Configuration> Next, referring to FIG. 7, the hardware configuration of the above-mentioned control unit 50 will be described in order. FIG. 7 is a schematic diagram showing an example of the hardware configuration of the control unit 50.

[0073] The control unit 50 includes a control circuit 101, a ROM (Read Only Memory) 102, a RAM (Random Access Memory) 103, a communication interface 104, and an auxiliary storage device 120. These components are connected to a bus 110.

[0074] The control circuit 101 is constituted by, for example, at least one integrated circuit. The integrated circuit can be constituted by, for example, at least one CPU (Central Processing Unit), at least one GPU (Graphics Processing Unit), at least one ASIC (Application Specific Integrated Circuit), at least one FPGA (Field Programmable Gate Array), or a combination thereof.

[0075] The control circuit 101 controls the operation of the control unit 50 by executing various programs such as the control program 122. The control program 122 is a program for realizing the various processes described in this specification. The control circuit 101 reads the control program 122 from the auxiliary storage device 120 or the ROM 102 into the RAM 103 based on receiving an execution instruction of the control program 122. The RAM 103 functions as a working memory and temporarily stores various data necessary for the execution of the control program 122.

[0076] The communication interface 104 is an interface for performing periodic communication with an external device using a field network. The external device includes, for example, the above-described valve 240, the heater 242 (see FIG. 9) described later, the above-described sensor 245, the above-described pressure sensor 246, the above-described temperature sensor 247, and the valves VA, VB (see FIG. 14) described later. As the field network, for example, EtherCAT (registered trademark), EtherNet / IP (registered trademark), CC-Link (registered trademark), or CompoNet (registered trademark) is adopted.

[0077] The auxiliary storage device 120 is, for example, a hard disk, a flash memory, an SSD (Solid State Drive), or other storage media. The auxiliary storage device 120 stores the control program 122 and the like. Note that the storage location of the control program 122 is not limited to the auxiliary storage device 120, and it may be stored in the storage area of the control circuit 101 (for example, cache memory, etc.), ROM 102, RAM 103, an external device (for example, a server), or the like.

[0078] The control program 122 may be provided incorporated into a part of an arbitrary program instead of as a single program. In this case, various processes according to the present embodiment are realized in cooperation with an arbitrary program. Even a program that does not include such a part of the module does not deviate from the gist of the control program 122 according to the present embodiment. Furthermore, part or all of the functions provided by the control program 122 may be realized by dedicated hardware. Furthermore, the control unit 50 may be configured in a form such as a so-called cloud service in which at least one server executes a part of the processing of the control program 122.

[0079] <F. Control Flow of the Valve> Next, with reference to FIG. 8, the control flow of the valve provided in the hydrogen utilization system 100 will be described. FIG. 8 is a flowchart showing the flow of the control process of the valve.

[0080] The process shown in FIG. 8 is realized by the control unit 50 of the hydrogen utilization system 100 executing the above-described control program 122 (see FIG. 7). In other aspects, part or all of the process may be executed by circuit elements or other hardware.

[0081] In step S110, the control unit 50 determines whether the above-described sufficient heating condition is satisfied. Since the sufficient heating condition is as described above, its description will not be repeated. When the control unit 50 determines that the above-described sufficient heating condition is satisfied (YES in step S110), it switches the control to step S130. Otherwise (NO in step S110), the control unit 50 switches the control to step S120.

[0082] In step S120, the control unit 50 controls the opening and closing of the main valves of the hydrogen utilization system 100 so that the combustible gas is supplied to the boiler 200. As an example, the control unit 50 opens the valve 240.

[0083] In step S130, the control unit 50 controls the opening and closing of the main valves of the hydrogen utilization system 100 so that the combustible gas is not supplied to the boiler 200. As an example, the control unit 50 closes the valve 240. Thereby, the supply of the combustible gas to the boiler 200 is stopped, and the hydrogen released from the hydrogen storage alloy 350 is supplied to the boiler 200.

[0084] <G. First Modified Example> Next, with reference to FIGS. 9 to 12, the hydrogen utilization system 100 according to the first modified example will be described. FIG. 9 is a diagram showing the configuration of the hydrogen utilization system 100 according to the first modified example.

[0085] In the example of FIG. 4 described above, the hydrogen utilization system 100 supplied the combustible gas to the boiler 200 until hydrogen was sufficiently supplied from the container 300 to the boiler 200. In contrast, the hydrogen utilization system 100 according to this modified example heats the container 300 with a heater until hydrogen is sufficiently supplied from the container 300 to the boiler 200. Then, the hydrogen utilization system 100 stops driving the heater based on the fact that hydrogen has been sufficiently supplied from the hydrogen storage alloy 350 to the boiler 200.

[0086] More specifically, the hydrogen utilization system 100 according to this modification example is different from the hydrogen utilization system 100 shown in FIG. 4 in that it includes a heater 242 instead of the valve 240 and the pipe F4.

[0087] The heater 242 is installed at a location where the container 300 can be heated and heats the container 300. As an example, the heater 242 may be provided on the container 300 or near the container 300. Here, the "nearby" means within the range where the heat from the heater 242 reaches the container 300.

[0088] Note that the heater 242 may be configured to heat the heat medium flowing through the pipes F2A and F2B instead of the container 300. In this case, the heater 242 may be provided on the pipes F2A and F2B or near the pipes F2A and F2B. Here, the "nearby" means within the range where the heat from the heater 242 reaches the pipes F2A and F2B.

[0089] The heater 242 is controlled by the control unit 50. When the condition indicating that the amount of hydrogen released from the hydrogen storage alloy 350 is equal to or greater than a predetermined amount (that is, the above-mentioned sufficient heating condition) is not satisfied, the control unit 50 drives the heater 242. On the other hand, when the above-mentioned sufficient heating condition is satisfied, the control unit 50 stops driving the heater 242.

[0090] As an example, the control unit 50 determines whether the above-mentioned sufficient heating condition is satisfied based on the detection value of the sensor 245. The sensor 245 is provided on the pipe F1. The sensor 245 is, for example, a temperature sensor and detects the temperature of the fluid flowing from the boiler 200 to the heat exchanger 250. In this example, the above-mentioned sufficient heating condition is satisfied when the temperature of the fluid detected by the sensor 245 is equal to or higher than a predetermined value (for example, 100 °C or higher).

[0091] More specifically, when the temperature of the fluid detected by the sensor 245 is lower than a predetermined value, the control unit 50 determines that the above-described sufficient heating condition is not satisfied. In this case, the control unit 50 starts driving the heater 242. That is, the control unit 50 outputs an ON command to the heater 242. As a result, the hydrogen storage alloy 350 is heated, and the supply of hydrogen from the container 300 to the boiler 200 is started.

[0092] On the other hand, when the temperature of the fluid detected by the sensor 245 is equal to or higher than the predetermined value, the control unit 50 determines that the above-described sufficient heating condition is satisfied. In this case, the control unit 50 stops driving the heater 242. That is, the control unit 50 outputs an OFF command to the heater 242.

[0093] Note that the sensor 245 does not necessarily have to be a temperature sensor. As another example, the sensor 245 may be a flow rate sensor. In this example, the above-described sufficient heating condition is satisfied when the flow rate detected by the sensor 245 is equal to or higher than a predetermined value.

[0094] More specifically, when the flow rate of the fluid detected by the sensor 245 is lower than a predetermined value, the control unit 50 determines that the above-described sufficient heating condition is not satisfied. In this case, the control unit 50 starts driving the heater 242. That is, the control unit 50 outputs an ON command to the heater 242. As a result, the hydrogen storage alloy 350 is heated, and the supply of hydrogen from the container 300 to the boiler 200 is started.

[0095] On the other hand, when the flow rate of the fluid detected by the sensor 245 is equal to or higher than a predetermined value, the control unit 50 determines that the above-described sufficient heating condition is satisfied. In this case, the control unit 50 stops driving the heater 242. That is, the control unit 50 outputs an OFF command to the heater 242.

[0096] FIG. 10 is a diagram for explaining another example regarding the method of determining whether or not the above-described sufficient heating condition is satisfied.

[0097] In the hydrogen utilization system 100 shown in FIG. 10, it is different from the hydrogen utilization system 100 shown in FIG. 9 in that a pressure sensor 246 is provided instead of the sensor 245. The pressure sensor 246 is provided in the pipe F3 and measures the pressure in the pipe F3 through which the hydrogen released from the hydrogen storage alloy 350 passes. In this example, the above-described sufficient heating condition is satisfied when the pressure detected by the pressure sensor 246 is equal to or higher than a predetermined value.

[0098] More specifically, when the pressure detected by the pressure sensor 246 is lower than the predetermined value, the control unit 50 determines that the above-described sufficient heating condition is not satisfied. In this case, the control unit 50 starts driving the heater 242. That is, the control unit 50 outputs an ON command to the heater 242. As a result, the hydrogen storage alloy 350 is heated, and the supply of hydrogen from the container 300 to the boiler 200 is started.

[0099] On the other hand, when the pressure detected by the pressure sensor 246 is equal to or higher than the predetermined value, the control unit 50 determines that the above-described sufficient heating condition is satisfied. In this case, the control unit 50 stops driving the heater 242. That is, the control unit 50 outputs an OFF command to the heater 242.

[0100] FIG. 11 is a diagram for explaining still another example regarding a method for determining whether or not the above-described sufficient heating condition is satisfied.

[0101] In the hydrogen utilization system 100 shown in FIG. 11, it is different from the hydrogen utilization system 100 shown in FIG. 9 in that a temperature sensor 247 is provided instead of the sensor 245. The temperature sensor 247 is provided at any location where the temperature of the hydrogen storage alloy 350 can be directly or indirectly detected. The temperature sensor 247 may be provided on the surface of the container 300, may be provided inside the container 300, or may be provided near the container 300 so as to detect the ambient temperature around the container 300. In this example, the above-described sufficient heating condition is satisfied when the temperature detected by the temperature sensor 247 is equal to or higher than a predetermined value.

[0102] More specifically, when the temperature detected by the temperature sensor 247 is lower than a predetermined value, the control unit 50 determines that the above-described sufficient heating condition is not satisfied. In this case, the control unit 50 starts driving the heater 242. That is, the control unit 50 outputs an ON command to the heater 242. As a result, the hydrogen storage alloy 350 is heated, and the supply of hydrogen from the container 300 to the boiler 200 is started.

[0103] On the other hand, when the temperature detected by the temperature sensor 247 is equal to or higher than the predetermined value, the control unit 50 determines that the above-described sufficient heating condition is satisfied. In this case, the control unit 50 stops driving the heater 242. That is, the control unit 50 outputs an OFF command to the heater 242.

[0104] Next, with reference to FIG. 12, the control flow of the heater 242 will be described. FIG. 12 is a flowchart showing the flow of the control process of the heater 242.

[0105] The process shown in FIG. 12 is realized by the control unit 50 of the hydrogen utilization system 100 executing the above-described control program 122 (see FIG. 7). In other aspects, part or all of the process may be executed by circuit elements or other hardware.

[0106] In step S210, the control unit 50 determines whether or not the above-described sufficient heating condition is satisfied. Since the sufficient heating condition is as described above, the description thereof will not be repeated. When the control unit 50 determines that the above-described sufficient heating condition is satisfied (YES in step S210), the control is switched to step S230. Otherwise (NO in step S210), the control unit 50 switches the control to step S220.

[0107] In step S220, the control unit 50 drives the heater 242. That is, the control unit 50 outputs an ON command to the heater 242. As a result, the hydrogen storage alloy 350 is heated, and the supply of hydrogen from the container 300 to the boiler 200 is started.

[0108] In step S230, the control unit 50 stops driving the heater 242. That is, the control unit 50 outputs an OFF command to the heater 242.

[0109] <H. Second Modified Example> Next, with reference to FIG. 13, a hydrogen utilization system 100 according to the second modified example will be described.

[0110] In the above example, the hydrogen utilization system 100 was composed of one container 300. However, the hydrogen utilization system 100 may be composed of a plurality of containers 300.

[0111] Preferably, the plurality of containers 300 are configured as a cartridge. A cartridge is a framework that houses a plurality of containers 300. FIG. 13 is a view showing the cartridge 400 from the front.

[0112] As shown in FIG. 13, the cartridge 400 is configured to be able to house a plurality of containers 300. In the example of FIG. 13, the cartridge 400 houses 12 containers 300.

[0113] As described with reference to FIG. 3 above, each of the containers 300 is composed of a main body 310, a heat medium inlet 315A, a heat medium outlet 315B, a hydrogen discharge port 320, and a valve 325.

[0114] Each outlet 315B of the container 300 is connected to the inlet 315A of another container 300 via the pipe 410. More specifically, first, the heat medium is sent from the above-described pipe F2A (see FIG. 1 etc.) to the candle 400. Next, the heat medium is sent to the inlet 315A of the first container 300 via the pipe 410. Then, the heat medium is sent from the outlet 315B of the first container 300 to the inlet 315A of the second container 300 via the pipe 410. In this way, the heat medium flows through each of the plurality of containers 300 in order and is discharged from the candle 400. The heat medium discharged from the candle 400 is sent to the above-described pipe F2B (see FIG. 1 etc.).

[0115] Each discharge port 320 of the container 300 is connected by the pipe 420. As a result, the hydrogen discharged from each of the containers 300 is discharged collectively through the pipe 420. The pipe 420 is connected to, for example, the above-described pipe F3 (see FIG. 2).

[0116] In this way, since the hydrogen utilization system 100 is composed of the candle 400 including a plurality of containers 300, the supply of hydrogen becomes more sustainable.

[0117] In the above description, an example in which the candle 400 houses a plurality of containers 300 has been described. However, the candle 400 may be composed of one or more containers 300. Therefore, in this specification, the candle 400 is synonymous with one or more containers 300.

[0118] <I. Third Modification Example> Next, with reference to FIGS. 14 and 15, the hydrogen utilization system 100 according to the third modification example will be described. FIG. 14 is a diagram showing the configuration of the hydrogen utilization system 100 according to the third modification example.

[0119] The hydrogen utilization system 100 according to this modification example includes candles 400A and 400B. Each of the candles 400A and 400B corresponds to the candle 400 shown in FIG. 13 above. Note that the number of candles included in the hydrogen utilization system 100 may be one or three or more.

[0120] In this modified example, the above-described pipe F2A (see FIG. 2) branches from the branch point PA into pipes F2A1 and F2A2. Pipe F2A1 is connected to the inlet of the heat medium in the candle 400A. Pipe F2A2 is connected to the inlet of the heat medium in the candle 400B.

[0121] A valve VA is provided in the pipe F2A1. The valve VA is a switching mechanism (first switching mechanism) capable of switching whether or not to supply the heat medium to the candle 400A. The valve VA is configured to be able to switch its opening / closing state between at least two states: an open state and a closed state. The opening degree of the valve VA may be adjustable or may be constant. When the valve VA is in the open state, the heat medium is supplied to the candle 400A. On the other hand, when the valve VA is in the closed state, the supply of the heat medium to the candle 400A stops.

[0122] A valve VB is provided in the pipe F2A2. The valve VB is a switching mechanism (second switching mechanism) capable of switching whether or not to supply the heat medium to the candle 400B. The valve VB is configured to be able to switch its opening / closing state between at least two states: an open state and a closed state. The opening degree of the valve VB may be adjustable or may be constant. When the valve VB is in the open state, the heat medium is supplied to the candle 400B. On the other hand, when the valve VB is in the closed state, the supply of the heat medium to the candle 400B stops.

[0123] In this modified example, the above-described pipe F2B (see FIG. 2) branches from the branch point PB into pipes F2B1 and F2B2. Pipe F2B1 is connected to the outlet of the heat medium in the candle 400A. Pipe F2B2 is connected to the outlet of the heat medium in the candle 400B.

[0124] The hydrogen utilization system 100 according to this modification example controls the opening and closing of valves VA and VB to sequentially switch the supply of the heat medium to the candles 400A and 400B. As a result, the candles 400A and 400B are used up. As a result, the hydrogen supply time to the boiler 200 becomes longer.

[0125] When the hydrogen supply amount from the candle 400A decreases, when the valve VA of the candle 400A is closed and at the same time the valve VB of the next candle 400B is opened, the candle 400B is not sufficiently heated. Therefore, the hydrogen supply amount temporarily decreases. Therefore, when switching from the candle 400A to the next candle 400B, the hydrogen utilization system 100 secures the time to open both valves VA and VB. Then, based on the fact that the candle 400B is sufficiently heated, the hydrogen utilization system 100 closes the valve VA. As a result, the hydrogen utilization system 100 can continue to supply hydrogen to the boiler 200.

[0126] With reference to FIG. 15, a more specific processing example will be described. FIG. 15 is a diagram schematically showing the control flow of the valves VA and VB.

[0127] In step S1, the control unit 50 controls the valve VA so as to supply the heat medium to the candle 400A (first container), and controls the valve VB so as to stop the supply of the heat medium to the candle 400B (second container). That is, the control unit 50 opens the valve VA and closes the valve VB. As a result, the heat medium flows into the candle 400A, and hydrogen is supplied from the candle 400A. At this time, the heat medium does not flow into the candle 400B.

[0128] In step S2, it is assumed that the amount of hydrogen released from the hydrogen storage alloy 350 in the cartridge 400A has become equal to or less than a predetermined amount. Based on this, the control unit 50 controls the valve VB so as to supply the heat medium to the cartridge 400B. That is, the control unit 50 opens the valve VB. At this time, the control unit 50 controls the valve VA so as to maintain the supply of the heat medium to the cartridge 400A. That is, the control unit 50 maintains the valve VA in the open state. As a result, the heat medium flows to both of the cartridges 400A and 400B.

[0129] Note that whether or not the amount of hydrogen released from the cartridge 400A has become equal to or less than a predetermined amount is determined by various methods. As an example, the control unit 50 uses the above-described pressure sensor 246 provided in the pipe F3 to determine whether or not the amount of hydrogen released from the cartridge 400A has become equal to or less than a predetermined amount. More specifically, the control unit 50 determines that the amount of hydrogen released from the cartridge 400A has become equal to or less than a predetermined amount when the pressure detected by the pressure sensor 246 becomes lower than a predetermined value.

[0130] In step S3, it is assumed that the amount of hydrogen released from the hydrogen storage alloy 350 in the cartridge 400B has become more than a predetermined amount. Based on this, the control unit 50 controls the valve VA so as to stop the supply of the heat medium to the cartridge 400A. That is, the control unit 50 closes the valve VA.

[0131] Note that whether or not the amount of hydrogen released from the cartridge 400B has become more than a predetermined amount is determined by various methods. As an example, the control unit 50 uses the above-described pressure sensor 246 provided in the pipe F3 to determine whether or not the amount of hydrogen released from the cartridge 400B has become more than a predetermined amount. More specifically, the control unit 50 determines that the amount of hydrogen released from the cartridge 400B has become more than a predetermined amount when the pressure detected by the pressure sensor 246 becomes higher than a predetermined value.

[0132] As another example, the control unit 50 may determine that the amount of hydrogen released from the cartridge 400B is greater than a predetermined amount based on the elapse of a predetermined time after the valve VB is opened.

[0133] As described above, by controlling the valves VA and VB, the hydrogen utilization system 100 can continuously supply hydrogen to the boiler 200.

[0134] In the above description, an example in which two valves VA and VB are controlled has been described, but three or more valves may be controlled.

[0135] <J. Fourth Modification Example> In the above example, until hydrogen is sufficiently supplied from the container 300 to the boiler 200, the container 300 is heated by supplying the combustible gas to the boiler 200 or is heated by the heater 242. However, in an environment where the temperature is high such as in summer, the container 300 can release hydrogen by being heated by air. For example, when the temperature is 30°C or higher, the container 300 releases hydrogen by heat exchange with air. In this case, a configuration for heating the container 300 is not necessarily required.

[0136] <K. Others> In this way, by using the hydrogen utilization system 100 disclosed above, the boiler 200 can use the hydrogen released from the hydrogen storage alloy 350 as fuel. Further, the waste heat of the boiler 200 is used by the hydrogen storage alloy 350, and the hydrogen storage alloy 350 releases hydrogen. By using hydrogen as fuel, greenhouse gas emissions can be reduced, contributing to some activities of the Sustainable Development Goals (SDGs).

[0137] It should be considered that the embodiments disclosed this time are illustrative in all respects and not restrictive. The scope of the present invention is shown not by the above description but by the claims, and it is intended that all modifications within the meaning and scope equivalent to the claims are included.

Explanation of Reference Numerals

[0138] 50 Control Unit, 100 Hydrogen Utilization System, 101 Control Circuit, 102 ROM, 103 RAM, 104 Communication Interface, 110 Bus, 120 Auxiliary Storage Device, 122 Control Program, 200 Boiler, 240 Valve, 242 Heater, 245 Sensor, 246 Pressure Sensor, 247 Temperature Sensor, 250 Heat Exchanger, 300 Container, 310 Main Body, 315A Inlet, 315B Outlet, 320 Discharge Port, 325 Valve, 350 Hydrogen Storage Alloy, 400 Candle, 400A Candle, 400B Candle, 410 Pipe, 420 Pipe, F1 Pipe, F2A Pipe, F2A1 Pipe, F2A2 Pipe, F2B Pipe, F2B1 Pipe, F2B2 Pipe, F3 Pipe, F4 Pipe, P1 Branch Point, PA Branch Point, PB Branch Point, VA Valve, VB Valve.

Claims

1. A boiler and a container containing a hydrogen storage alloy, wherein the container is configured to be directly or indirectly heated by a fluid discharged from the boiler. A system.

2. The container is configured to be able to heat the hydrogen storage alloy by heat exchange with a heat medium, wherein the heat medium is heated by the fluid. The system according to claim 1.

3. The boiler is a hydrogen combustion boiler using hydrogen as fuel, wherein the hydrogen combustion boiler is configured to use hydrogen released from the hydrogen storage alloy as fuel when the fluid heats the heat medium. The system according to claim 2.

4. The boiler further uses combustible gas as fuel, and the system further includes a control unit and a switching mechanism capable of switching whether to supply combustible gas to the boiler, wherein the control unit controls the switching mechanism so that the combustible gas is supplied to the boiler when a condition indicating that the amount of hydrogen released from the hydrogen storage alloy is not less than a predetermined amount is not satisfied, and controls the switching mechanism so that the combustible gas is not supplied to the boiler when the condition is satisfied. The system according to claim 3.

5. The system further includes a control unit and a heater for heating the container or the heat medium, wherein the control unit drives the heater when a condition indicating that the amount of hydrogen released from the hydrogen storage alloy is not less than a predetermined amount is not satisfied, and stops driving the heater when the condition is satisfied. The system according to claim 2 or 3.

6. The system further includes a control unit, a plurality of the containers, a first switching mechanism capable of switching whether to supply the heat medium to a first container among the plurality of containers, and a second switching mechanism capable of switching whether to supply the heat medium to a second container among the plurality of containers, wherein the control unit controls the first switching mechanism to supply the heat medium to the first container and controls the second switching mechanism to stop supplying the heat medium to the second container, When the amount of hydrogen released from the hydrogen storage alloy in the first container becomes equal to or less than a predetermined amount, a process of controlling the second switching mechanism so as to supply the heat medium to the second container; When the amount of hydrogen released from the hydrogen storage alloy in the second container becomes greater than a predetermined amount, a process of controlling the first switching mechanism so as to stop the supply of the heat medium to the first container is executed. The system according to claim 2 or 3.

7. The system according to any one of claims 1 to 4, wherein the fluid is exhaust gas of the boiler or feed water heated by the boiler.

8. The system according to any one of claims 1 to 4, wherein the hydrogen storage alloy is heated to 10°C or higher and 60°C or lower by the fluid.

Images