Hydrogen storage system

Abstract

To provide a hydrogen storage system that allows hydrogen to be quickly used.SOLUTION: A hydrogen storage system 20 comprises a plurality of hydrogen storage parts (tanks 30A, 30B, 30C, and 30D) capable of storing hydrogen in an incorporated hydrogen storage material, remaining amount detection means for detecting the remaining amount of the hydrogen stored in the hydrogen storage parts, and hydrogen transfer means (temperature adjustment devices 50A, 50B, 50C, and 50D) for moving the hydrogen from a hydrogen storage part in which the remaining amount of the hydrogen is equal to or smaller than a predetermined amount, to another hydrogen storage part.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a hydrogen storage system. [Background technology]

[0002] The following Patent Document 1 discloses a hydrogen supply facility that transfers hydrogen from a card to a hydrogen storage alloy tank and supplies hydrogen from the hydrogen storage alloy tank. The hydrogen storage alloy tank absorbs hydrogen when cooled and releases hydrogen when heated. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2017-219152 A Summary of the Invention [Problem to be solved by the invention]

[0004] The technology of Patent Document 1 can reduce the amount of hydrogen remaining in the tank. However, when the amount of hydrogen in the hydrogen storage alloy tank is small, the internal pressure of the hydrogen storage alloy tank is low, and it takes a long time to heat the tank until the internal pressure is high enough to release hydrogen. In this case, it is difficult to use the hydrogen quickly.

[0005] In consideration of the above, an object of the present invention is to provide a hydrogen storage system that allows hydrogen to be used quickly. [Means for solving the problem]

[0006] The hydrogen storage system of claim 1 comprises a plurality of hydrogen storage units capable of storing hydrogen in an incorporated hydrogen storage material, a remaining amount detection means for detecting the remaining amount of hydrogen stored in the hydrogen storage units, and a hydrogen transfer means for transferring hydrogen from one hydrogen storage unit in which the remaining amount of hydrogen falls below a predetermined amount to another hydrogen storage unit.

[0007] One method for releasing hydrogen from a hydrogen storage material is to heat the hydrogen storage unit to increase the internal pressure. However, when the amount of hydrogen remaining in the hydrogen storage unit is small, the internal pressure is low and it takes a long time to heat the hydrogen storage unit to a pressure sufficient to release hydrogen.

[0008] Therefore, the hydrogen storage system of claim 1 includes a plurality of hydrogen storage units, and transfers hydrogen from a hydrogen storage unit whose remaining amount of hydrogen is equal to or less than a predetermined amount to another hydrogen storage unit. In other words, hydrogen in a hydrogen storage unit whose remaining amount of hydrogen is equal to or less than a predetermined amount is transferred to another hydrogen storage unit before being sent to a demand facility.

[0009] Therefore, when hydrogen is sent to a facility that requires it, it is not necessary to heat a hydrogen storage unit with a small amount of hydrogen remaining for a long period of time, but it is sufficient to heat a hydrogen storage unit that has been replenished with hydrogen and has a large amount of hydrogen remaining for a short period of time.This allows hydrogen to be used quickly.

[0010] The hydrogen storage system of claim 2 is the hydrogen storage system of claim 1, in which the hydrogen transfer means is a temperature control device provided for each hydrogen storage unit and capable of heating or cooling the hydrogen storage unit to create a pressure difference between the hydrogen storage units.

[0011] In the hydrogen storage system of claim 2, a pressure difference is generated between the hydrogen storage units by heating or cooling the hydrogen storage units. For example, when the pressure increases by heating a hydrogen storage unit in which the remaining amount of hydrogen is below a predetermined amount, hydrogen can be transferred to another hydrogen storage unit with a relatively lower pressure. Also, when the pressure decreases by cooling another hydrogen storage unit, hydrogen can be transferred from the hydrogen storage unit with a relatively higher pressure in which the remaining amount of hydrogen is below a predetermined amount.

[0012] Furthermore, since a temperature adjustment device is provided for each hydrogen storage unit, hydrogen can be supplied according to the demand by simply heating an appropriate number of hydrogen storage units according to the demand for hydrogen.

[0013] The hydrogen storage system of claim 3 is the hydrogen storage system according to claim 2, wherein outside air can be used as a heat source for the temperature adjustment device.

[0014] In the hydrogen storage system of claim 3, outside air can be used as a heat source for the temperature adjustment device. Therefore, the hydrogen storage unit can be heated using outside air during the day when the temperature is high. This allows for less energy consumption compared to heating the hydrogen storage unit at night. In addition, the hydrogen storage unit can be cooled using outside air at night when the temperature is low. This allows for less energy consumption compared to cooling the hydrogen storage unit during the day. Effect of the Invention

[0015] According to the present invention, hydrogen can be utilized quickly. [Brief description of the drawings]

[0016] [Figure 1] FIG. 2 is a schematic diagram showing a state in which hydrogen is being supplied from a tank in one module to a demand facility in a hydrogen storage system according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a schematic diagram showing a state in which hydrogen is supplied from tanks in multiple modules to a demand facility in a hydrogen storage system according to an embodiment of the present invention. [Diagram 3] FIG. 2 is a schematic diagram showing a state in which the remaining amount of hydrogen in a tank of one module is low in the hydrogen storage system according to the embodiment of the present invention. [Figure 4] FIG. 2 is a schematic diagram showing a hydrogen storage system according to an embodiment of the present invention in a state where hydrogen is not being supplied to demand facilities and the amount of hydrogen remaining in a tank of one module is low. [Diagram 5] FIG. 1 is a schematic diagram showing a hydrogen storage system according to an embodiment of the present invention, in a state in which hydrogen is not being supplied to a demand facility and hydrogen is being transferred from a tank in a module with a low remaining amount of hydrogen to a tank in another module. [Figure 6]FIG. 1 is a schematic diagram showing a hydrogen storage system according to an embodiment of the present invention, in which hydrogen is being supplied to a demand facility and hydrogen is being transferred from a tank in a module with a low remaining amount of hydrogen to a tank in another module. [Figure 7] FIG. 11 is a schematic diagram showing a state in which hydrogen is being transferred from a tank of a module with a low remaining amount of hydrogen to a tank of another module by cooling the tank to which hydrogen is being transferred in a hydrogen storage system according to an embodiment of the present invention. [Figure 8] 10 is a schematic diagram showing a modified example of a gas pipe in the hydrogen storage system according to the embodiment of the present invention. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] Hereinafter, a hydrogen storage system according to an embodiment of the present invention will be described with reference to the drawings. Components indicated by the same reference numerals in each drawing are the same components. However, unless otherwise specified in the specification, each component is not limited to one, and may be present in multiple numbers.

[0018] In addition, explanations of configurations and symbols that are duplicated in each drawing may be omitted. Note that the present disclosure is not limited to the following embodiments, and may be implemented by making appropriate modifications, such as omitting configurations, replacing them with different configurations, or combining one embodiment and various modified examples, within the scope of the purpose of the present disclosure.

[0019] <Hydrogen storage system> The hydrogen storage system 20 shown in Fig. 1 is a system for supplying hydrogen to a demand facility 10 provided in a building. One example of the demand facility 10 is a fuel cell. Hydrogen is used to reduce peak values ​​of electricity demand and peak values ​​of heat demand related to hot water use. The demand facility 10 may also be an emergency power supply device or the like.

[0020] The hydrogen storage system 20 includes a plurality of modules 20A, 20B, 20C, and 20D. The modules 20A-20D include temperature adjustment devices 50A, 50B, 50C, and 50D, respectively. The hydrogen storage system 20 also includes a gas pipe 60 that is piped from the demand facility 10 in the building to the modules 20A-20D, and a control device 80. The control device 80 is electrically connected to a pressure gauge (not shown, described below), the temperature adjustment devices 50A-50D, the switching valves 40A-40D, and the switching valves 42A-42D.

[0021] (Module) The modules 20A to 20D are housings installed in a building. The modules 20A to 20D are, for example, boxes with openable and closable doors, and are made of stainless steel or the like. The module 20A has a plurality of tanks 30A (four tanks, for example) arranged vertically. The tanks 30A are hydrogen storage alloy tanks that incorporate a hydrogen storage alloy (not shown) capable of absorbing and releasing hydrogen.

[0022] Hydrogen is filled into tank 30A at a hydrogen production facility outside the building. The tank 30A filled with hydrogen is transported from the hydrogen production facility to the building and installed in module 20A. The hydrogen in tank 30A installed in module 20A is used by demand equipment 10 in the building. Tank 30A with a reduced amount of hydrogen can be replaced with a tank 30A filled with hydrogen.

[0023] Each tank 30A is provided with a pressure gauge (not shown). The internal pressure of the tank 30A indicated by this pressure gauge indicates the amount of hydrogen in the tank 30A. For example, a decrease in the internal pressure of the tank 30A indicates that the amount of hydrogen in the tank 30A is reduced. The internal pressure of the tank 30A is acquired by the control device 80.

[0024] Similar to module 20A, modules 20B-20D are provided with tanks 30B-30D, respectively. Similar to tank 30A, tanks 30B-30D are hydrogen storage alloy tanks, and a description thereof will be omitted. Each of tanks 30A-30D is an example of a hydrogen storage section in the present invention. Also, the pressure gauge is an example of a remaining amount detection means in the present invention.

[0025] (Temperature adjustment device) The temperature adjustment devices 50A-50D are devices that heat the tanks 30A-30D of the modules 20A-20D with hot air or cool them with cold air, respectively. The temperature adjustment devices 50A-50D are an example of the hydrogen transfer means in the present invention, and are controlled by the control device 80. In the following description, the temperature adjustment devices 50A-50D may be collectively referred to as the temperature adjustment device 50.

[0026] The temperature adjustment device 50A is equipped with a heat exchanger and a fan (not shown). For example, the temperature adjustment device 50A can heat outside air by exchanging heat with a refrigerant, and emit warm air (air with a higher temperature than the outside air without heat exchange) toward the tank 30A in the module 20A. When emitting warm air, it is preferable to heat the daytime outside air, which has a relatively high temperature. In other words, it is preferable to use the daytime outside air as a heat source. Note that exhaust heat from the demand facility 10, etc. may also be used as a heat source.

[0027] The temperature adjustment device 50A can also cool the outside air by exchanging heat with the refrigerant, and emit cold air (air with a lower temperature than the outside air without heat exchange) toward the tank 30A in the module 20A. When emitting cold air, it is preferable to cool the outside air at night, which has a relatively low temperature. In other words, it is preferable to use the outside air at night as a cold heat source.

[0028] The temperature adjustment devices 50B to 50D have the same configuration as the temperature adjustment device 50A, and detailed description thereof will be omitted. Although the temperature adjustment devices 50A to 50D can heat and cool the outside air, they may be capable of performing at least one of heating and cooling.

[0029] (Gas Pipe) The gas pipe 60 is a hydrogen supply pipe arranged across the modules 20A-20D and connected to the demand facility 10. Branch pipes 60A-60D are connected in series to the gas pipe 60. The branch pipes 60A-60D are connected to the gas pipe 60 in order from the side farthest from the demand facility 10.

[0030] The branch pipe 60A is a gas pipe connected to the tank 30A. Similarly, the branch pipes 60B to 60D are gas pipes connected to the tanks 30B to 30D, respectively.

[0031] The branch pipe 60A has a main pipe connected to the gas pipe 60, and branch pipes further connected in parallel to the main pipe to the multiple tanks 30A. The number of branch pipes can be appropriately changed depending on the number of tanks 30A. The same applies to the branch pipes 60B to 60D.

[0032] (Switching valve) The branch pipe 60A is provided with a switching valve 40A. A switching valve 40A is provided for each branch pipe, and they are all controlled by the control device 80. Similarly, the branch pipes 60B to 60D are provided with branch pipes 60B to 60D controlled by the control device 80. Note that the switching valves 40A to 40D may be provided in the main pipes, rather than in the branch pipes of the branch pipes 60A to 60D, respectively.

[0033] A switching valve 42A is provided in the gas pipe 60. The switching valve 42A is disposed closer to the demand facility 10 than the branch pipe 60A. Similarly, switching valves 42B to 42D are provided in the gas pipe 60. The switching valves 42B to 42D are disposed closer to the demand facility 10 than the branch pipes 60B to 60D, respectively.

[0034] In each drawing, the switching valves 40A to 40D and the switching valves 42A to 42D shown in black are in a closed state, and the switching valves 40A to 40D and the switching valves 42A to 42D shown in white are in an open state. The same applies to the switching valves 44A to 44D and the switching valves 46A to 46D described later.

[0035] <Use of hydrogen> When hydrogen from the hydrogen storage system 20 is used, hydrogen may be supplied to the demand facility 10 from any one of the modules 20A-20D, or hydrogen may be supplied to the demand facility 10 from multiple locations among the modules 20A-20D. The number of module locations to which hydrogen is supplied is determined by the control device 80 according to the amount of hydrogen demand in the demand facility 10.

[0036] (1 module use) For example, Fig. 1 shows a state in which hydrogen is being supplied from module 20A (tank 30A) to demand facility 10. In Fig. 1, thick arrows drawn along gas pipe 60 indicate the flow of hydrogen. This is the same in other figures. In this state, control device 80 opens switching valves 40A, 42A-42D and closes switching valves 40B-40D.

[0037] The control device 80 then controls the temperature adjustment device 50A to emit hot air toward the tank 30A in the module 20A. This increases the internal pressure of the tank 30A, and hydrogen is supplied to the demand facility 10 via the branch pipe 60A and the gas pipe 60.

[0038] In each of the tanks 30A to 30D in each of the drawings, the hatched portion conceptually indicates the remaining amount of hydrogen in the tank.

[0039] (Use of multiple modules) 2 also shows a state in which hydrogen is being supplied from modules 20A-20C (tanks 30A-30C) to demand facility 10. In this state, controller 80 opens switching valves 40A-40C and 42A-42D and closes switching valve 40D.

[0040] The control device 80 controls the temperature adjustment devices 50A-50C to emit hot air toward the tanks 30A-30C in the modules 20A-20C. This increases the internal pressure of the tanks 30A-30C, and hydrogen is supplied to the demand facility 10 via the branch pipes 60A-60B and the gas pipe 60.

[0041] (Pre-heating) FIG. 3 shows a state in which hydrogen is being supplied from module 20A to demand facility 10 and the amount of hydrogen remaining in tank 30A is low. When hydrogen in tank 30A is being used, control device 80 intermittently acquires the internal pressure of tank 30A. When the internal pressure of tank 30A falls below a predetermined value, control device 80 predicts the time when the hydrogen in tank 30A will run out based on the rate at which the internal pressure of tank 30A decreases. The "predetermined value" can be set as appropriate.

[0042] Then, the control device 80 operates the other temperature adjustment devices 50 so that hydrogen can be immediately supplied from tanks in other modules 20B-20D to the demand facility 10 at the time when it is predicted that the hydrogen in the tank 30A will run out. For example, in Fig. 3, the control device 80 operates the temperature adjustment device 50B so that hydrogen can be supplied from the tank 30B in the module 20B to the demand facility 10.

[0043] When the hydrogen in the tank 30A runs out, the control device 80 closes at least one of the switching valves 40A and 42A and opens the switching valve 40B, thereby enabling hydrogen to be immediately supplied to the demand facility 10 from the tank 30B.

[0044] <Hydrogen transfer> Hydrogen in the hydrogen storage system 20 can be transferred between modules that do not supply hydrogen to the demand facility 10 .

[0045] For example, Figure 4 shows a state in which hydrogen is not being supplied to demand equipment 10 from any of modules 20A to 20D and the internal pressure in tank 30A is below a predetermined value (i.e., the remaining amount of hydrogen is below a predetermined amount).

[0046] In order to supply hydrogen from tank 30A to demand facility 10 from this state, tank 30A needs to be heated to increase the internal pressure. However, when the amount of hydrogen remaining in tank 30A is small, the internal pressure is low. Therefore, in order to obtain an internal pressure that allows hydrogen to be released, heating for a longer period of time is required compared to when the amount of hydrogen in tank 30A is large. In this case, it is difficult to immediately supply hydrogen to demand facility 10.

[0047] Therefore, in this hydrogen storage system 20, hydrogen is transferred from tank 30A in module 20A to tank 30B in module 20B, as shown in Figure 5. This transfer is performed during a time period when there is no need to supply hydrogen from tanks 30A and 30B to demand facility 10.

[0048] In this state, the control device 80 opens the switching valves 40A, 40B, and 42A, and closes the switching valve 42B.

[0049] Then, the control device 80 controls the temperature adjustment device 50A to emit hot air toward the tank 30A in the module 20A. This increases the internal pressure of the tank 30A, relatively lowering the internal pressure of the tank 30B, and hydrogen is supplied to the tank 30B of the module 20B via the branch pipes 60A, 60B and the gas pipe 60. As a result, the hydrogen in the tank 30A is depleted and transferred to the tank 30B.

[0050] In order to supply hydrogen to the demand facility 10 from this state, it is necessary to heat the tank 30B to increase the internal pressure, but because the tank 30B is refilled with hydrogen, it takes less time to heat the tank 30B to a pressure that allows hydrogen to be released compared to when the tank 30B is not refilled. This makes it easier to immediately supply hydrogen to the demand facility 10.

[0051] 4 and 5, the transfer of hydrogen in a state where hydrogen is not being supplied from any of modules 20A to 20D to the demand facility 10 has been described. However, the embodiment of the present invention is not limited to this. For example, in a state where hydrogen is being supplied from a module closer to the demand facility 10 to the demand facility 10, hydrogen may be transferred between modules farther from the demand facility 10.

[0052] For example, as shown in FIG. 6, while hydrogen is being transferred from module 20A to module 20B, hydrogen can be supplied to the demand facility 10 from module 20C, which is closer to the demand facility 10 than module 20B.

[0053] <Action and Effects> A hydrogen storage system 20 according to an embodiment of the present invention includes a plurality of hydrogen storage units (tanks 30A-30D), and when the remaining amount of hydrogen in one hydrogen storage unit falls below a predetermined amount, hydrogen is transferred to another hydrogen storage unit. For example, as shown in Fig. 5, hydrogen is transferred from tank 30A to tank 30B.

[0054] That is, when the remaining amount of hydrogen in tank 30A falls below a predetermined amount, the hydrogen is transferred to tank 30B before being sent to demand facility 10.

[0055] Therefore, when hydrogen is sent to the demand facility 10, there is no need to heat the tank 30A with a small amount of hydrogen remaining for a long period of time, and it is sufficient to heat the tank 30B with a large amount of hydrogen remaining after being replenished with hydrogen for a short period of time. This allows hydrogen to be used promptly.

[0056] Furthermore, in the hydrogen storage system 20 according to the embodiment of the present invention, a pressure difference is generated between the hydrogen storage units by heating or cooling the hydrogen storage units.

[0057] For example, when the tank 30A in which the remaining amount of hydrogen falls below a predetermined amount is heated and the pressure increases, hydrogen can be transferred to the tank 30B in which the pressure is relatively lower.

[0058] Furthermore, since a temperature adjustment device 50 is provided for each module 20A-20D (each tank 30A-30D), hydrogen can be supplied according to demand by simply heating an appropriate number of tanks 30A-30D, as shown in Figures 1 and 2.

[0059] Furthermore, in the hydrogen storage system 20 according to the embodiment of the present invention, outside air can be used as a heat source for the temperature adjustment device 50. Therefore, the tanks 30A-30D can be heated using the outside air during the day when the temperature is high. This allows for less energy consumption compared to heating the tanks 30A-30D at night. Furthermore, the tanks 30A-30D can be cooled using the outside air during the night when the temperature is low. This allows for less energy consumption compared to cooling the tanks 30A-30D during the day.

[0060] <Other embodiments> In the above embodiment, as shown in Fig. 5, the tank 30A in the source module 20A is "heated" to generate an internal pressure difference between the tanks 30A and 30B. This causes hydrogen to be supplied to the tank 30B in the module 20B, but the embodiment of the present invention is not limited to this.

[0061] 7, a difference in internal pressure may be created between tanks 30A and 30B by "cooling" tank 30B in destination module 20B. When the internal pressure of tank 30 is reduced, hydrogen can be transferred from tank 30A, which has a relatively high internal pressure, to tank 30B.

[0062] From the viewpoint of energy conservation, for example, in summer (or during the day) when the outside temperature is high, it is preferable to create an internal pressure difference between the tanks 30A and 30B by "heating" the tank 30A in the source module 20A. On the other hand, for example, in winter (or at night) when the outside temperature is low, it is preferable to create an internal pressure difference between the tanks 30A and 30B by "cooling" the tank 30B in the destination module 20B.

[0063] In the above embodiment, the hydrogen supply path from each of the tanks 30A to 30D to the demand facility 10 is used as a hydrogen transfer path between the tanks 30A to 30D, but the present invention is not limited to this embodiment.

[0064] 8, a gas pipe 70 for transferring hydrogen may be provided in addition to the gas pipe 60. Furthermore, regardless of the presence or absence of the gas pipe 70, branch pipes 60A to 60D can be connected to the gas pipe 60 in "parallel" via switching valves 44A to 44D.

[0065] Branch pipes 60A to 60D can be connected in parallel to the gas pipe 70 via switching valves 46A to 46D.

[0066] According to this embodiment, while hydrogen is supplied from any of the tanks 30A to 30D to the demand facility 10, hydrogen can be transferred between the remaining tanks 30A to 30D.

[0067] 8, switching valves 44A, 44C, and 44D are closed and switching valve 44B is opened, thereby supplying hydrogen from tank 30B to demand facility 10. Meanwhile, switching valves 46A and 46C are opened and switching valves 46B and 46D are closed, thereby transferring hydrogen from tank 30A to tank 30C.

[0068] Thus, in the present invention, the method of forming the gas pipe is arbitrary and can be appropriately selected depending on the desired method of use. [Explanation of symbols]

[0069] 30A tank (hydrogen storage section) 30B Tank (hydrogen storage section) 30C Tank (hydrogen storage section) 30D Tank (hydrogen storage section) 50A Temperature control device (hydrogen transfer means) 50B Temperature control device (hydrogen transfer means)

Claims

1. A plurality of hydrogen storage units capable of storing hydrogen in a built-in hydrogen storage material; a remaining amount detection means for detecting a remaining amount of hydrogen stored in the hydrogen storage section; a hydrogen transfer means for transferring hydrogen from the hydrogen storage unit when the remaining amount of hydrogen is equal to or less than a predetermined amount to another hydrogen storage unit; A hydrogen storage system equipped with

2. The hydrogen transfer means is a temperature adjustment device provided for each of the hydrogen storage units, capable of heating or cooling the hydrogen storage units to generate a pressure difference between the hydrogen storage units; The hydrogen storage system of claim 1 .

3. The temperature control device can use outside air as a heat source. The hydrogen storage system of claim 2 .

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