JP2002020101A - Hydrogen supply system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lightweight hydrogen supply system using an aqueous solution capable of storing hydrogen and causing no change in the hydrogen concentration in a fuel solution. SOLUTION: The hydrogen supply system is provided with a storage tank 11 storing the hydrogen-containing solution having high hydrogen concentration and a catalyst 12 for separating hydrogen from the hydrogen-containing solution and is structured to provide a recovery tank 14 for recovering a solution left after hydrogen is released by the catalyst from the hydrogen-containing solution. The recovery tank and the storage tank are each formed by partitioning a tank into two by a partition member and the partition member is formed movable to change the volume of the recovery tank and the storage tank.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydrogen supply system used for a fuel cell vehicle or the like, and more particularly to a hydrogen supply system suitable for reusing a hydrogen-containing solution.

[0002]

2. Description of the Related Art As a method for storing hydrogen as a fuel of a fuel cell or a hydrogen engine, a method of dissolving hydrogen in a solution is known. For example, as described in the Nihon Keizai Shimbun morning edition of May 7, 2000, a liquid in which a compound of metal lithium, boron, and hydrogen is dissolved in water can be given as an example. When this solution is brought into contact with a titanium-based catalyst or the like, hydrogen gas is generated at normal temperature and normal pressure. After the hydrogen gas is generated, the solution can be reused by dissolving the hydrogen again by blowing hydrogen.

[0003]

When such a solution capable of storing hydrogen is used in a fuel cell vehicle, a hydrogen vehicle, or the like, the following problems can be considered.

[0004] An aqueous solution in which hydrogen is dissolved at a high concentration (hereinafter, referred to as "fuel solution") emits hydrogen gas when passing through a catalyst, and an aqueous solution in which low-concentration hydrogen is dissolved (hereinafter, referred to as "recovery solution"). Becomes If this recovered solution is returned to the fuel solution tank as it is, the hydrogen concentration of the entire fuel solution in the tank will decrease. Hydrogen cannot be efficiently generated from a fuel solution having a reduced hydrogen concentration. Therefore,
There is a need for measures to keep the hydrogen concentration of the fuel solution high.
Here, the aqueous solution in which hydrogen is dissolved at a high concentration is the hydrogen-containing solution described in the claims, and the aqueous solution in which the hydrogen is dissolved at a low concentration is the solution after releasing the hydrogen described in the claims.

[0005] In addition, in maintaining the hydrogen concentration of the fuel solution high, it is not preferable that the weight and volume of the system increase. Therefore, a measure that can reduce the weight and volume of the system is required.

Therefore, in the present invention, when the hydrogen-containing solution is used in a fuel cell vehicle or the like, the above-mentioned problem of performance degradation does not occur, and the replenishment of the fuel solution and the discharge of the recovered solution are convenient. An object is to provide a high hydrogen supply system.

[0007]

In order to solve the above-mentioned problems, according to the present invention, there is provided a hydrogen supply system including a storage tank for storing a hydrogen-containing solution and a catalyst for separating hydrogen from the hydrogen-containing solution. In addition, a recovery tank for recovering the solution after releasing hydrogen from the hydrogen-containing solution by the catalyst is provided.

[0008] By doing so, the recovered solution can be stored in the recovery tank provided separately from the storage tank, and can be prevented from being mixed with the fuel solution. Therefore, the hydrogen concentration of the fuel solution does not decrease, and the amount of generated hydrogen does not decrease. Further, by adding a simple configuration such as having a residual fuel detecting means such as a water level sensor to the storage tank, the user can be notified of the amount of the residual fuel solution accurately.

According to a second aspect of the present invention, in the hydrogen supply system according to the first aspect, the recovery tank and the storage tank are containers formed by dividing one tank into two by a partition member. The partition member is configured to be movable so that the volumes of the collection tank and the storage tank can be changed.

By doing so, when the amount of the fuel solution is large and the amount of the recovered solution is small, the volume of the storage tank is increased, the volume of the recovery tank is reduced, and the amount of the fuel solution is reduced.
When the amount of the recovered solution is large, the partition member is moved to reverse the volume ratio, so that both the fuel solution and the recovered solution can be stored without increasing the volume of the entire tank.

[0011] In particular, in the structure of the invention of claim 2,
It is desirable to provide a valve capable of closing the passage in the middle of the passage for flowing the hydrogen-containing solution from the storage tank to the recovery tank.

In such a configuration, when a fuel solution is supplied to the storage tank after the valve is closed when a new fuel solution is supplied to the storage tank at the fuel solution supply stand, the internal pressure of the storage tank increases. As a result, the partition member automatically moves, and the capacity of the storage tank increases. At the same time, the volume of the recovery tank is reduced, and the recovery solution can be discharged from the recovery tank.

Further, in the structure of the first aspect of the present invention, a valve is provided for making the volume of the storage tank invariable, and for closing a part of a passage of the fuel solution from the storage tank to the catalyst, the passage being provided. The fuel solution supply port of the tank may also be configured to be able to be sealed.

In this manner, when replenishing the fuel solution, high-pressure nitrogen gas is introduced together with the fuel solution, and the replenishing port is closed. Replenishment can be performed smoothly using the pressure of nitrogen gas.

Further, in the structure of the first or second aspect of the present invention, a pressure is applied to the recovery tank by providing a valve or the like capable of closing a passage from the catalyst to the recovery tank. Alternatively, the recovery tank may be provided with a gas inlet for feeding compressed air or nitrogen gas.

In this way, when the recovery solution is discharged from the recovery tank at the stand, low-pressure (0.2 to 0.3 MPa) air or nitrogen gas is discharged from a portion different from the recovery solution outlet. The collected solution can be smoothly discharged by being fed.

The fuel solution supply port to the storage tank and the recovery solution discharge port from the recovery tank are integrally provided with two pipes adjacent to each other. It is desirable to be able to connect the solution discharge hoses simultaneously.

By doing so, it is possible to prevent a mistake in forgetting to connect the supply hose or the discharge hose. In particular, it is still more preferable to change the shape of the connection portion so that the supply hose and the discharge hose cannot be connected in reverse.

It is also desirable that the storage tank be provided with a residual fuel solution detecting means such as a water level sensor and a mechanism for informing the driver or the like of the residual fuel solution amount. With such a configuration, a driver or the like can check the remaining fuel solution amount.

[0020]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a block diagram of a hydrogen supply system and a fuel cell according to a first embodiment of the present invention.

The hydrogen supply system 10 according to the first embodiment mainly includes a storage tank 11, a hydrogen generator 13 having a catalyst 12, and a recovery tank 14.

The storage tank 11 is a tank for storing a fuel solution in which high-concentration hydrogen is dissolved. Storage tank 1
1 includes a supply port 16 for replenishing the hydrogen-containing solution at the stand, and a passage 2 for feeding the hydrogen-containing solution to the hydrogen generator 13.
0 and an air vent (not shown) are provided. Further, the storage tank 11 is provided with a remaining fuel detecting means (not shown) such as a water level sensor, and has a device for notifying a user such as a driver of the remaining fuel solution amount. The supply port 16 is provided with a check valve 19a that can flow only in the entering direction so that the hydrogen-containing solution in the storage tank 11 does not flow backward.
In the passage 20 leading from the storage tank 11 to the hydrogen generator 13, the hydrogen-containing solution in the storage tank 11 is filled with the hydrogen generator 13.
A pump 17 for transporting the oil to the container is provided. In addition,
A hydrogen-containing solution is a liquid in which a compound of lithium, boron and hydrogen is dissolved in water, and can dissolve hydrogen, and can generate hydrogen at normal temperature and pressure when exposed to a titanium-based catalyst. It is.

The hydrogen generator 13 has a titanium-based catalyst 12 inside, and generates hydrogen gas to supply the hydrogen gas to the fuel cell 15 when flowing a hydrogen-containing solution.

The recovery tank 14 is a tank for storing a recovery solution which is a hydrogen-containing solution whose hydrogen concentration has been reduced by sufficient generation of hydrogen gas by the hydrogen generator 13. It is desirable that the capacity of the recovery tank 14 be equal to or larger than that of the storage tank 11 so that all the fuel solution in the storage tank 11 can be accommodated. Hydrogen generator 1
3 and the recovery tank 14 communicate with each other through a passage 21, and a check valve 19 c is provided in the middle of the passage 21 so that the hydrogen-containing solution flows only toward the recovery tank. When a certain amount of the collected solution has accumulated in the collection tank 14, the collected solution must be discharged. Therefore, the collection tank 14 is provided with a discharge port 18 for discharging the collected solution by a stand or the like. The discharge port 18 is provided with a check valve 19b so that the collected solution flows only in the discharge direction. Since the discharge of the recovered solution and the replenishment of the fuel solution usually need to be performed simultaneously, the discharge port 18 is provided integrally with the replenishing port 16 adjacent to the replenishing port 16. The storage tank 11 and the collection tank 1
4 may be formed separately or may be formed by dividing an integral tank into two parts by a partition member.

As described above, the hydrogen supply system 10 includes the recovery tank 14 separately from the storage tank 11 so as to store the fuel solution and the recovery solution separately, and further includes the supply port 16 and the discharge port 18. Are installed integrally next to each other.

The hydrogen supply system configured as described above operates as follows. When a fuel cell vehicle or the like is turned on, the fuel solution stored in the storage tank 11 is passed through the passage 20 by the pump 17 through the hydrogen generator 1.
Conveyed to 3. The fuel solution that has entered the hydrogen generator 13
By touching the catalyst 12, hydrogen is generated. The generated hydrogen is supplied as fuel to the fuel cell. The hydrogen-containing solution that has generated hydrogen in the hydrogen generator 13 has a low hydrogen concentration, and as a recovery solution, passes through the passage 21 through the recovery tank 14.
Transported to When the fuel solution in the storage tank 11 is running low, the recovery solution in the recovery tank 14 is full, and it is necessary to recover the recovery solution and supply the fuel solution.

When replenishing the fuel solution at the stand,
A supply / discharge hose (not shown) of a stand, which can be simultaneously connected to both the supply port 16 and the discharge port 18 installed next to each other, is connected to supply a fuel solution to the storage tank and a recovery tank. The draining of the recovered solution from is performed simultaneously.

As described above, according to the hydrogen supply system 1, since the recovery tank 14 is provided separately from the storage tank 11, the recovered solution having a low hydrogen concentration does not mix with the fuel solution. Therefore, since the hydrogen concentration in the fuel solution does not decrease, it is possible to prevent the amount of generated hydrogen from decreasing. In addition, the supply port 16 and the discharge port 18 are integrally installed next to each other so that the supply hose and the discharge hose of the stand can be connected at the same time. It is possible to prevent mistakes in forgetting to recover the solution or overflowing the recovered solution. Further, since the discharge hose and the supply hose can be connected at the same time, the work can be speeded up.

Next, a second embodiment of the present invention will be described. FIG. 2 is a block diagram of a hydrogen supply system according to the second embodiment. Note that the same reference numerals are given to substantially the same portions as those in the first embodiment, and detailed description is omitted.

The hydrogen supply system 30 according to the second embodiment is characterized in that the storage tank 31 and the recovery tank 32 are partitioned by a partition wall 33 which is a movable partition member. The entire tank including the storage tank 31 and the recovery tank 32 has a fan-shaped column shape, and the partition wall 33 is rotatably supported around a rotation support shaft 34 at the center of the fan. I have. A sealing member 36 is provided between the partition wall 33 and the fan wall 35 which is a curved surface of the fan arc of the entire tank so that the fuel solution and the recovered solution are not mixed. The partition wall 33 can rotate and move in accordance with the volume ratio of the fuel solution and the recovered solution. However, if the partition wall 33 moves outside the end of the fan wall 35, the fuel solution and the recovered solution are mixed. Therefore, stoppers 37a and 37b are provided on both sides of the end of the fan wall 35, respectively.
In addition to the pump 17, a valve 3 for opening and closing the passage 20 is provided in the passage 20 leading from the storage tank 31 to the hydrogen generator 13.
8 are provided.

The hydrogen supply system 30 configured as described above operates as follows. When the storage tank 31 is filled with the fuel solution, the partition wall 33 is located on the recovery tank side and is in contact with the stopper 37b. When the hydrogen supply system 30 is operating, the valve 3
Numeral 8 is open, and the fuel solution in the storage tank 31 is sequentially transported to the hydrogen generator 13 by the pump 17. Pump 1
When the fuel solution is conveyed by 7, the pressure in the storage tank 31 decreases, while the pressure in the recovery tank 32 increases because the recovered solution is pushed from the hydrogen generator 13 through the passage 21. The storage tank 31 and the recovery tank 3
Due to the pressure difference of 2, the partition wall 33 moves to the storage tank 31 side, so that the partition wall 33 corresponds to the volume ratio between the fuel solution and the recovered solution so that the internal pressures of the storage tank 31 and the recovery tank 32 become the same. Position.

When the fuel solution has been used up, it is necessary to replenish the fuel solution and simultaneously discharge the recovered solution. At this time, at the stand, a supply / discharge hose (not shown) is connected, and the fuel solution is pressure-fed to the storage tank 31 with the valve 38 closed. When the fuel solution is pressure-fed to the storage tank 31, the internal pressure of the storage tank 31 increases, so that the partition wall 33 moves toward the recovery tank 32 accordingly. When the partition wall 33 moves to the recovery tank 32 side, the recovery solution does not flow to the passage 21 side by the check valve 19c, and is discharged to the outside through the discharge port 18. In addition,
Even when there is no check valve 19c, if the backflow to the passage 21 is prevented by the valve 38, the discharge port 18
From which the recovered solution can be discharged.

As described above, in the hydrogen supply system 30,
By making the partition wall 33 of the storage tank 31 and the recovery tank 32 movable, the volume of the entire tank can be distributed to the storage tank 31 and the recovery tank 32 according to the volume ratio between the fuel solution and the recovery solution. Therefore, the volume of the entire tank can be reduced to about half as compared with the case where the partition wall 33 does not move, and the hydrogen supply system can be reduced in size and weight, and the weight of the fuel cell vehicle and the like can be reduced. . Also, by providing a valve 38 in the passage 20 and closing and replenishing the valve 38 when replenishing the fuel solution, the partition wall 33 is automatically moved to the collection tank 32 side at the same time as the replenishment of the fuel solution, and further, the collected solution is discharged. It can be discharged from the outlet 18. The hydrogen supply system 30
In the above, since the position of the partition wall 33 indicates the remaining amount of the fuel solution, a sensor for detecting the position of the partition wall 33 may be provided to detect the remaining amount of the fuel solution.

Next, a third embodiment of the present invention will be described. FIG. 3 is a block diagram of a hydrogen supply device according to a third embodiment of the present invention. In the third embodiment, portions substantially the same as those in the first and second embodiments are denoted by the same reference numerals, and detailed description is omitted.

The hydrogen supply system 40 according to the third embodiment is provided with a valve 43 that can open and close the passage 20 in the passage 20 that leads from the storage tank 41 to the hydrogen generator 13. The provision of the gas inlet 44 into which air can be introduced provides a feature in the method of transporting the fuel solution and discharging the recovered solution.

The storage tank 41 and the recovery tank 42 of the hydrogen supply system 40 are configured so that their volumes are not changed. The gas suction port 44 has a collection tank 42 from outside.
The check valve 19d is provided so that air flows only in the direction of. Further, since the check valve 19a is also provided in the supply port 16 of the storage tank 41, the storage tank 41 can be sealed to apply pressure. In the storage tank 41 and the recovery tank 42, the passages 2 are provided so that the fuel solution and the recovery solution flow smoothly.
0 and the outlet 18 are provided below the tank. The method of sealing the storage tank 41 is based on the check valve 19.
In addition to the method according to a, a valve or a lid may be used.

The hydrogen supply system 40 having the above configuration operates as follows. When replenishing the storage tank 41 with the fuel solution, a high-pressure chemically stable nitrogen gas is simultaneously fed from the replenishment port 16 with the fuel solution while the valve 43 is closed. In this way, the fuel solution tends to exit the passage 20 due to the high pressure of the nitrogen gas. Therefore, by adjusting the valve 43, an appropriate amount of the fuel solution can be sent to the hydrogen generator 13. That is, the fuel solution can be transported without providing a pump as in the first and second embodiments.

When discharging the recovery solution from the recovery tank 42, compressed air is supplied from the gas suction port 44 while the discharge connector is connected to the discharge port. In this case, since the volume of the collection tank 42 does not change, the collection tank 4
The internal pressure of the tank 2 is increased, and the collected solution can be discharged from the outlet 18 below the collection tank 42.

Although the embodiment of the present invention has been described above, the present invention is not limited to the above embodiment. For example, regarding the positions of the pump 17, the valve 38, and the valve 43, they do not necessarily have to be in the passage 20, but may be provided in the passage 21.
This can be changed as appropriate according to the ease of transporting the hydrogen-containing solution and adjusting the flow rate. Further, the third embodiment can be appropriately combined with the second embodiment for implementation. That is, it is possible to move the partition wall appropriately according to the volume ratio of the fuel solution and the recovered solution while applying high pressure to the storage tank. further,
The hydrogen-containing solution used in the hydrogen supply system of the present invention may generate hydrogen gas even in portions other than the hydrogen generator 13. Therefore, when hydrogen gas is generated in the passage, it is conceivable that the transportation of the fuel solution becomes impossible. Therefore, a gas reservoir for appropriately degassing can be provided according to the shape of the passage. Further, the storage tank and the recovery tank may be appropriately provided with a valve for adjusting the internal pressure or degassing. Also,
In the above embodiment, the hydrogen supply system is used for the fuel cell. However, the present invention is not limited to the fuel cell, and can be used for a device using hydrogen as a fuel, for example, a hydrogen engine.

[0040]

As described in detail above, according to the first aspect of the present invention, the recovered solution can be stored in the recovery tank provided separately from the storage tank, so that the recovered solution and the fuel solution do not mix. . Therefore, the hydrogen concentration in the fuel solution does not decrease as the traveling distance of the fuel cell vehicle or the like increases, and it is possible to prevent the amount of generated hydrogen from decreasing.

According to the second aspect of the present invention,
Since the volumes of the storage tank and the recovery tank can be adjusted according to the volumes of the fuel solution and the recovery solution, the volume of the entire tank including the storage tank and the recovery tank can be reduced, and as a result, the fuel cell vehicle And the like can be reduced in size and weight.

[Brief description of the drawings]

FIG. 1 is a block diagram of a hydrogen supply system according to a first embodiment of the present invention.

FIG. 2 is a block diagram of a hydrogen supply system according to a second embodiment of the present invention.

FIG. 3 is a block diagram of a hydrogen supply system according to a third embodiment of the present invention.

[Explanation of symbols]

11, 31, 41 ... storage tank, 12 ... catalyst, 14, 3
2, 42 ... collection tank, 33 ... partition wall

Claims (2)

[Claims] 1. A hydrogen supply system comprising a storage tank for storing a hydrogen-containing solution and a catalyst for separating hydrogen from the hydrogen-containing solution, wherein the solution after releasing hydrogen from the hydrogen-containing solution by the catalyst is provided. A hydrogen supply system comprising a recovery tank for recovering hydrogen. 2. The collection tank and the storage tank are containers formed by dividing one tank into two by a partition member, and the partition member is movable so as to change the volumes of the collection tank and the storage tank. The hydrogen supply system according to claim 1, wherein the hydrogen supply system is provided.