JPH0224762B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a metal hydride container suitable for storing and extracting heat using a metal hydride.

(b) Prior art Certain metals or alloys react reversibly with hydrogen, and attempts are currently being made to utilize the heat of reaction generated at this time for heat storage, etc. Various proposals for chemical containers have been made.

However, conventional metal hydride containers of this type
For example, as seen in the conventional example of JP-A No. 58-47989, the structure is complicated, such as installing a pressure-resistant container filled with metal hydride and a heat exchanger separately, and connecting them with a heat pipe. Moreover, since the metal hydride and the pressure vessel come into direct contact with each other, heat loss through the pressure vessel increases. In addition, vertical fins are attached to the heat pipe in the longitudinal direction to improve heat transfer between the metal hydride and the heat pipe, but when the metal hydride is pulverized due to repeated absorption and release of hydrogen gas. However, there was a drawback that the contact between the fins and the metal hydride was reduced and the heat exchange function was deteriorated.

On the other hand, in order to eliminate such drawbacks, the above-mentioned publication discloses that a heat pipe is placed outside the container, a metal hydride is filled inside the container to absorb and release hydrogen, and the outside of the heat pipe is A proposal has been made for a container configuration in which a heat exchanger is attached to the container to store and extract heat, but if the metal hydride container is configured in this way, the disadvantage is that sensible heat loss due to the pressure container body becomes large. It was hot.

In addition, in both cases, heat exchange is performed between the metal hydride and the heating medium via the heat pipe, which increases heat transfer resistance, causes sensible heat loss, and reduces the heat transfer rate. There were also some drawbacks.

(c) Problems to be solved by the invention The present invention reduces the sensible heat loss caused by the pressure vessel, improves the heat transfer state between the metal hydride and the heating medium, and produces a metal hydride with high heat exchange efficiency. The purpose is to provide a container.

(d) Means for Solving the Problems Therefore, the present invention provides a method in which heat transfer fins are arranged along the axial direction inside a cylindrical container through which a heat medium tube passes through in an airtight manner, and a metal hydride is housed inside the cylindrical container. Furthermore, a hydrogen conduit with a filter that allows hydrogen to permeate is attached to the end of the cylindrical container to form a heat exchanger, and this heat exchanger is covered with a heat insulating material whose surface is coated with a film with excellent heat insulation properties to make it resistant to pressure. Place it in a container,
It is characterized in that the heat medium pipe and the hydrogen conduit are communicated with the outside from both ends of the pressure-resistant container via connection joints made of a material with excellent heat insulation properties.

(E) Effect During heat regeneration, the heat of reaction transferred from the metal hydride to the heat medium tube is efficiently transferred to the heat medium without being conducted to the pressure vessel because the heat medium tube is insulated from the pressure vessel and is transferred to the outside. It is taken out. In addition, the coating on the surface of the insulation material prevents hydrogen from entering the insulation material surrounding the heat exchanger, which prevents hydrogen from transferring heat from the surface of the heat exchanger body to the pressure vessel, significantly reducing heat loss. do.

(f) Examples The examples shown in the drawings will be described in more detail below.

Each figure shows a configuration diagram of a metal hydride container according to an embodiment of the present invention, in which FIG. 1 is a side view, FIG. 2 is a front sectional view, and FIG. 3 is a side sectional view.

As shown in these figures, the metal hydride container of this embodiment includes a heat exchange container 3 housed inside a pressure-resistant container 1 with a heat insulating material 2 interposed therebetween. The heat exchange container 3
The cylindrical container 5 has a heat transfer pipe 6 inserted therethrough and a hydrogen conduit 7 attached to the cylindrical container 5 for storing the metal hydride 4. In order to seal the metal hydride 4 inside the cylindrical container 5, Seal members 8 and 9 are inserted between 5 and hydrogen conduit 7 and between cylindrical container 5 and heat medium pipe 6.

That is, the sealing member 8 is made of a cylindrical body made of stainless steel, for example, and has a threaded groove carved on its outer circumferential surface, and the hydrogen conduit 7 is fixed in advance to its inner circumferential surface. This sealing member 8 with the hydrogen conduit 7 is screwed into a screw hole previously formed in the end face of the cylindrical container 5. Thereby, the hydrogen conduit 7 can be attached to the cylindrical container 5 in an airtight manner. Note that a filter 7a is formed at the tip of the hydrogen conduit 7 through which hydrogen can pass but not metal hydride powder.

On the other hand, the seal member 9, like the seal member 8, is provided with a threaded groove on its outer circumferential surface, and its inner circumferential surface is formed in a tapered shape that gradually widens toward the axial tip. The portion of the heat transfer pipe 6 to which the seal member 9 is attached is also formed in a tapered shape that widens toward the inside of the cylindrical container 5, corresponding to the tapered shape of the inner circumferential surface of the seal member 9. Therefore, if the heat medium pipe 6 is passed through a screw hole previously formed in the center of the end face of the cylindrical container 5, the seal member 9 is passed through the heat medium pipe 6, and the seal member 9 is screwed into the screw hole. The heat medium pipe 6 and the seal member 9 are airtightly fixed by their tapered joint,
Airtightness is maintained between the cylindrical container 5 and the seal member 9 by screwing them together.

In this way, the metal hydride 4 is stored inside the cylindrical container 5 to which the hydrogen conduit 7 and the heat medium tube 6 are airtightly attached via the seal members 8 and 9. In order to improve heat conduction between the heat medium pipe 6 and the heat medium pipe 6, a plurality of heat transfer fins 10 are arranged radially from the heat medium pipe 6 to the cylindrical container 5 along the axial direction of the heat medium pipe 6.

On the other hand, on the pressure vessel 1 side, joints 11 and 12 are provided to connect the heat medium pipe 6 and hydrogen conduit 7 disposed inside the vessel to external pipes 6' and 7'. This joint 11 has thread grooves carved on both the inner and outer circumferences, while the joint 12 has thread grooves formed only on the outer circumference, and the tips of the external pipes 6' and 7' are formed on the inner circumference in the axial direction of the inner circumference. It is inserted and fixed halfway.

In order to connect the heat medium pipe 6, the hydrogen pipe 7, and the external pipes 6' and 7' using these joints, the pressure vessel 1
First, the joint 11 is screwed and fixed into each screw hole formed at a predetermined position on the end surface 1a and the cover plate 1b. Next, the joint 12 to which the external pipes 6' and 7' are fixed is screwed into the inside of the joint 11. This results in
Airtightness is maintained between the pressure vessel 1 and the joint 11 and between the joints 11 and 12 by screwing them together. At this time, if you want to make the airtightness even more perfect, you can interpose an O-ring 13 made of an elastic material between the flange of the joint 11 and the pressure vessel 1, and between the flanges of the joints 11 and 12. Good. Additionally, the areas between each joint 12 and the external pipes 6' and 7' are sealed by the previously performed fixing process, and the areas between the heat medium pipe 6, hydrogen pipe 7, and the joint 12 are sealed with the heat medium pipe 6 described above. An airtight structure is formed in the same manner as in the case of joining the members 9.

Here, the reason why the joint has a double structure of 11 and 12 is to improve the heat insulation between the heat medium pipe 6, the hydrogen pipe 7 and the pressure vessel 1.The joint 11 is made of metal, and the joint 12 is made of metal. It is preferable that the joints 11 and 12 be made of a material with excellent heat insulation properties such as Teflon or fired ceramics, but the joints 11 and 12 may be made of the opposite material.

In this way, the heat exchange container 3 is almost completely thermally isolated from the outside air and sealed inside the pressure container 1.
In order to improve the heat insulation inside the pressure vessel 1, the heat insulating material 2 interposed between the pressure vessel 1 and the heat exchange vessel 3 has a surface coated with a film that is difficult to permeate hydrogen and has excellent heat insulation properties. There is. Further, the entire interior is sealed by flange joining of the main body of the pressure vessel 1 and the lid plate 1b, thereby forming a metal hydride.

With the above configuration, during heat storage, heat from the heat medium flowing through the heat medium pipe 6 from the external pipe 6' is uniformly transferred to the metal hydride 4 via the surface of the heat medium pipe 6 and the heat transfer fins 10. . At this time, from the heat medium to the pressure vessel 1
The heat conduction to the metal hydride 4 is prevented by the heat insulating joint 12 and conducted to the heat exchange container 3 without heat loss, and the heat is efficiently supplied to the metal hydride 4. The metal hydride 4 is dehydrogenated by the heat supplied from this heating medium and returns to the original metal. Also, the generated hydrogen gas is filtered through filter 7.
The hydrogen is taken out from the hydrogen conduit 7 to the external pipe 7' via a, and stored in a hydrogen cylinder (not shown). On the other hand, during heat dissipation, hydrogen gas supplied from the external pipe 7' through the hydrogen conduit 7 and through the filter 7a is
It combines with metal hydride 4 to generate heat. This generated heat is prevented from being transferred to the pressure vessel 1 by the heat insulating material 2, and all of the heat is transferred to the heat transfer fins 10 and the heat medium pipe 6.
Heat is transferred from the surface to the heating medium flowing inside it,
It is efficiently taken out to the external piping 6' and utilized.

In this way, in this embodiment, the cylindrical container 5
A hydrogen conduit 7, with seal members 8 and 9 interposed therein,
Since the heat medium pipe 6 is provided, the inside of the cylindrical container 5 is kept airtight, and leakage of hydrogen gas from the cylindrical container 5 is prevented. Furthermore, since the surface of the heat insulating material 2 is coated with a coating material that is difficult for hydrogen to permeate and has excellent heat insulating properties, even if hydrogen gas leaks from the cylindrical container 5, the amount will be limited to a very small area around it. ,
Heat loss through hydrogen gas is also prevented, and efficient heat exchange can be expected. In addition, since the joints 11 and 12 are interposed between the heat medium flow path and the pressure vessel 1 and between the hydrogen flow path and the pressure vessel 1, the airtightness inside the pressure vessel 1 is maintained, and the heat medium pipe 6 or the heat loss from the hydrogen conduit 7 to the pressure vessel 1 is also significantly reduced, resulting in a metal hydride vessel with extremely high thermal efficiency.

Note that polymer materials such as cellophane and polypropylene (treated with Saran coating) are promising as coating materials that are difficult for hydrogen to permeate and have excellent heat insulation properties. This is because its hydrogen permeability is about 1/100 to 1/1000 of Teflon, which is commonly used as a structural material, and its insulation properties are lower than metals with low hydrogen permeability (such as Al). This is because it increases by about 1000 times. (For example, Polymer Materials Handbook, edited by the Society of Polymer Science and Technology, 1971, published by Corona Publishing, Nos. 1297-1299)
p., Chemical Industry Handbook, edited by the Society of Chemical Engineers, 1968,
Published by Maruzen, pp. 58-59) (G) Effects of the Invention As described above, according to the present invention, heat transfer from the heat medium flow path and the hydrogen flow path to the pressure vessel is suppressed, and at the same time, heat transfer due to hydrogen gas is suppressed. Since heat transfer from the exchange container body to the pressure container is also suppressed, sensible heat loss due to the pressure container can be significantly reduced, and a metal hydride container with excellent heat exchange efficiency can be obtained.

[Brief explanation of drawings]

FIG. 1 is a side view of a metal hydride container according to an embodiment of the present invention, FIG. 2 is a front sectional view taken along line AA,
FIG. 3 is a side sectional view thereof. 1...Pressure container, 1a...End face, 1b...Lid plate, 2...
Heat insulating material, 3... Heat exchange container, 4... Metal hydride, 5
...Cylindrical container, 6...Heat medium pipe, 6', 7'...External piping,
7... Hydrogen conduit, 7a... Filter, 8, 9... Seal member, 10... Heat transfer fin, 11, 12... Joint,
13...O ring.

Claims (1)

[Claims] 1 A heat transfer fin is arranged along the axial direction inside a cylindrical container through which a heat medium pipe passes airtightly,
A heat exchanger is constructed by storing a metal hydride and attaching a hydrogen conduit with a filter to the end of the cylindrical container to allow hydrogen to pass through.This heat exchanger is coated with a coating material that is difficult for hydrogen to pass through and has excellent heat insulation properties. The heat transfer pipe and the hydrogen pipe are installed in a pressure-resistant container whose surface is covered with a heat-insulating material coated with heat-insulating material, and the heat transfer pipe and hydrogen pipe are led out from both ends of the pressure-resistant container through connection joints made of a material with excellent heat insulation properties. Characteristic metal hydride containers.