JP2002295798A - Hydrogen transport vessel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hydrogen transport vessel storing a hydrogen occlusion alloy which is efficient in filling and emission of hydrogen, and easy in manufacturing and filling hydrogen occlusion alloy powder. SOLUTION: This hydrogen transport vessel using the hydrogen occlusion alloy comprises a cylindrical buckle comprising a plurality of outer side perforated metal sheets and inner side super-dense filter cloth structures, a spiral element which is disposed concentrically in the buckle and comprises a spiral fin on the outer side and a double pipe for passing hot/cold water for heat exchange, a finely-powdered hydrogen occlusion alloy filled in a space formed of the buckle and the spiral element, a temperature sensor for detecting the temperature of hydrogen in the vessel, and a pressure sensor for detecting the pressure of hydrogen in the vessel.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a container for storing a hydrogen storage alloy, and more particularly to a container for efficiently filling a stored hydrogen storage alloy with hydrogen and releasing hydrogen from the hydrogen storage alloy. The present invention relates to a hydrogen transport container provided.

[0002]

2. Description of the Related Art In recent years, hydrogen storage alloy cylinders (also referred to as containers) have attracted attention as means for storing and supplying hydrogen as a fuel for a small fuel cell power supply in terms of safety, small and compact structure, and the like. It is used in battery cars and the like. If the hydrogen storage alloy cylinder is filled with hydrogen at a certain pressure and lower than room temperature, the rate of hydrogen storage, which is an exothermic reaction, increases. In addition, increasing the pressure also increases the hydrogen storage speed.
On the other hand, extraction (release) of hydrogen from the hydrogen storage alloy cylinder
It is generally known that if is carried out at a certain pressure and at a temperature higher than room temperature, the rate of hydrogen release as an endothermic reaction becomes faster.

Further, since the amount of hydrogen that can be stored in the hydrogen storage alloy cylinder is limited, if the hydrogen in the cylinder decreases or becomes empty during operation of the power supply, the cylinder must be replaced with a new one. No. In this case, the used cylinder is repeatedly used by replenishing (filling) hydrogen. The replenishment (filling) of hydrogen into the hydrogen storage alloy cylinder is performed at a hydrogen station provided with a hydrogen supply tank having a hydrogen storage alloy storing hydrogen. Also,
The transportation and supply of hydrogen from a hydrogen production plant or a relay station to each hydrogen station is performed using a vehicle equipped with a large hydrogen storage alloy container (large cylinder).

As described above, a container (cylinder) for storing a hydrogen storage alloy is required to be not only a reaction container for performing an endothermic / exothermic reaction but also a heat exchanger having high heat exchange efficiency. Under such circumstances, shortening the time required for replenishing (filling) hydrogen from the tank in the hydrogen production plant to the hydrogen transport vehicle and supplying (discharging) hydrogen from the hydrogen transport vehicle to the hydrogen station; That is, the development of a hydrogen storage alloy transport container having high heat exchange efficiency has been strongly desired.

[0005] As prior art in which a hydrogen storage alloy cylinder is used as a heat exchanger, there are JP-A-7-280492 and JP-A-2000-111193. JP 7
In JP-A-280492, the heat medium is introduced into the heat medium inlet from the outside of the holding container, and discharged outside from the heat medium outlet on the opposite side. Therefore, the flow rate of the heat medium in the container cannot be increased, so that the heat medium has a laminar flow, and the efficiency of heat exchange with the hydrogen storage alloy is not very good. Further, a filter (sintered filter) for separating hydrogen from the fine powdery hydrogen storage alloy is disposed at the center of the thin tube, and has a structure in which the filtration area cannot be increased.

In Japanese Patent Application Laid-Open No. 2000-111193, a unit composed of a corrugated plate and a flat plate is combined to improve the heat exchange efficiency between the hydrogen storage alloy and a heat medium. However, the hydrogen storage alloy is a fine powder, and it is difficult to ensure the sealing property between the filter plate (side plate) and the corrugated plate due to problems of manufacturing accuracy and thermal deformation. In addition, the structure is such that the value of the filtration area with respect to the amount of the hydrogen storage alloy cannot be increased.

On the other hand, Japanese Patent Application Laid-Open No. 2000-128502 discloses a prior art for improving a method of filling a vehicle equipped with a hydrogen engine or a fuel cell with hydrogen. According to this publication, when filling a hydrogen storage tank with a hydrogen storage alloy of a vehicle with hydrogen at a hydrogen station having a hydrogen supply tank having a hydrogen storage alloy storing hydrogen, the hydrogen storage alloy is used in the hydrogen storage tank. A technique is disclosed in which the amount of heat generated is effectively used in a hydrogen station to heat a hydrogen storage alloy necessary for releasing hydrogen, thereby achieving energy saving. FIG. 2 of this publication shows a hydrogen supply (storage) tank.

In FIG. 2 of this publication, a hydrogen supply tank (and a hydrogen storage tank) has an outer cylinder and an inner cylinder inside thereof, and has an outer peripheral surface of the outer cylinder and an outer peripheral surface of the inner cylinder. A path of pure water as a heat medium is formed between the surfaces. The outer cylinder has an inlet pipe protruding from one end wall and an outlet pipe protruding from the other end wall, and the insides of both pipes communicate with passages. Hydrogen inlet / outlet pipes penetrating the inner and outer cylinders are attached to both end walls on the inlet pipe side in an airtight manner. An open end of a porous hydrogen inlet / outlet pipe as a metal filter is fitted to the inner end of the hydrogen inlet / outlet pipe, and the closed other end is located near the other end wall of the inner cylinder. A plurality of disc-shaped alloy units are supported on the hydrogen inlet / outlet pipe by fitting their center holes and adjoining one another, and the outer peripheral surfaces of these alloy units are fitted to the inner peripheral surface of the inner cylinder. Is done. Each alloy unit is a thin and disk-shaped aluminum container filled with a powdered hydrogen storage alloy and hermetically sealed.

However, according to the above-mentioned prior art filling method, the temperature adjustment (heating or cooling) of the hydrogen storage alloy is performed only on the outer peripheral side, and the pure water flow is turbulent on the outer peripheral surface of the inner cylinder. Since no attempt has been made to adjust the temperature, the temperature of the powdered hydrogen storage alloy has not been sufficiently adjusted, and the effect of shortening the filling time has been insufficient. In addition, it is difficult to seal the alloy unit with the hydrogen-absorbing alloy in a close-packed manner, and it has a structure in which the value of the filtration area with respect to the amount of the hydrogen-absorbing alloy cannot be increased.

[0010] In order to improve the heat conduction of the hydrogen storage alloy, a unique alloy has been developed in which a microencapsulated alloy is obtained by subjecting an alloy powder to a wet electroless plating of a copper film having good heat conductivity. However, alloys microencapsulated for the purpose of improving the heat conduction are expensive, and it is economically difficult to employ them.

[0011]

SUMMARY OF THE INVENTION The present invention solves the above problem so that a hydrogen density equal to or higher than that of liquid hydrogen can be obtained without requiring a high pressure.
Its purpose is to efficiently fill and release hydrogen,
An object of the present invention is to provide a hydrogen transport container storing a hydrogen storage alloy which is easy to manufacture and facilitates a filling operation of the hydrogen storage alloy powder.

[0012]

According to a first aspect of the present invention, there is provided a hydrogen transporting container using a hydrogen storage alloy, which is disposed in the container. A cylindrical buckle composed of a plurality of outer-surface porous metal thin plates and an inner-surface ultra-close-packed filter cloth structure; A spiral element having a double pipe through which cold water passes, a fine powdered hydrogen storage alloy filled in a space formed by the buckle and the spiral element, and a temperature sensor for detecting a hydrogen temperature in the container; And a pressure sensor for detecting the hydrogen pressure in the container. Further, in the second invention mainly based on the first invention, a copper tube having a spiral unevenness on an inner surface is used as the spiral element in the first invention. Further, in a third invention mainly based on the first invention, a copper tube having a spiral baffle plate on an inner surface is used as the spiral element in the first invention.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The storage of hydrogen in a hydrogen storage alloy contained in a buckle in a hydrogen transport container according to the present invention is performed by flowing cold water through the inner surface of a spiral element having spiral fins for heat exchange. Then, hydrogen is supplied from the hydrogen pipe while monitoring the pressure sensor attached to the hydrogen pipe for hydrogen supply / discharge and controlling the inside of the pressure vessel to a constant pressure. The release of hydrogen was monitored by monitoring the pressure sensor attached to the hydrogen supply / discharge hydrogen pipe while the hot water was flowing through the inside of the spiral element with spiral fins for heat exchange. While controlling to a constant pressure, hydrogen is discharged from the hydrogen pipe. The temperature of hot and cold water at the time of storing and releasing hydrogen and the pressure in the pressure vessel are set in accordance with the storage alloy component.

In order to improve the efficiency of heat exchange with the heat medium, it is important to create turbulence in the heat medium. It has been confirmed by experiments that the heat exchange efficiency when the heat medium flows in a turbulent flow is significantly improved as compared with the case where the heat medium flows in a laminar flow. This is achieved by the second and third inventions of the present invention. That is, by passing hot and cold water at a high pressure to some extent through a spiral element having spiral fins for heat exchange and providing spiral-shaped projections on the inner surface, it becomes easy to create a turbulent flow of hot and cold water, so heat conduction is good. Becomes Further, by providing the spiral baffle on the inner surface of the spiral element, the flow of the hot and cold water becomes remarkably turbulent, and the heat conduction is further improved. Further, heat is uniformly transmitted to the powdery hydrogen storage alloy by the copper spiral fin attached to the outer surface of the spiral element.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS. 1 is an overall configuration diagram of a hydrogen transport container according to an embodiment of the present invention, FIG. 2 is a cross-sectional view taken along a line AA in FIG. 1, FIG. 3 is an explanatory diagram of a configuration of a spiral element, and FIG. Embodiment in which a spiral projection is provided on the inner surface, FIG. 5 is an explanatory view of a spiral baffle inserted into the inner surface of the spiral element.

First, the structure of the hydrogen transport container according to the present invention will be described with reference to FIG. Hydrogen transport container 1 according to the present invention
Is a steel plate made of steel plate with a pressure resistance of 1 MPa, a thickness of 3 mm, and an outer diameter of 300 mm.
A vessel (tank) 11 having a length of 1000 mm, a hydrogen pipe 13 for supplying and discharging hydrogen having a pressure sensor 20, a hot / cold water inlet pipe 16 and an outlet pipe 17 for heat exchange, and a cylinder inside the pressure vessel 11 Three buckles 12 for enclosing a hydrogen-absorbing alloy, each having a plurality of hydrogen-passing holes 24, and a holding element having three ultra-close-packed filter cloth structures formed of a porous aluminum thin plate having an outer surface thickness of 0.6 mm. 25. At the center of the buckle, a spiral element 14 for passing hot and cold water for heat exchange, having a copper double pipe on the inner surface (inside the tube) and copper spiral fins 23 with a 10 mm pitch (interval) on the outer surface (outside the tube).
Are arranged. The hot and cold water flows in from the inner pipe and flows out from the outer side of the inner pipe 28. Each inlet and outlet is connected to the hot and cold water inlet pipe 16 and the hot and cold water outlet pipe 17 of the pressure vessel. 0.1 for hydrogen storage alloy buckle
Each 1 kg of a Ti-V-Cr-based hydrogen storage alloy 15 finely pulverized to not more than μm is filled, and a temperature sensor 19 is mounted in the hydrogen storage alloy buckle.

Here, the structure of the above-described buckle 12 for enclosing a hydrogen storage alloy will be described. The base body 26 of the buckle 12 is formed in a cylindrical shape as shown in FIG. An ultra-close-packed filter cloth structure on the inner surface of the base 26 of the buckle (opening amount 0.005 to 0.01 μm)
Is coated with a filter 27 made of Tyranno fiber or the like. This filter blocks passage of the hydrogen storage alloy powder of about 0.1 μm and allows only hydrogen gas to pass. As this filter, a filter having a heat resistant temperature of 100 to 200 ° C. is used. As described above, since the buckle 12 has the outer surface porous aluminum thin plate and the inner surface ultra-fine filter cloth structure, the buckle 12 can sufficiently follow the expansion and contraction of the volume due to hydrogen storage and release of the hydrogen storage alloy.

Next, the flow of the heat medium in the heat exchanger will be described. The second invention and the third invention in the present invention have been made by paying attention to the fact that the flow of the heat medium (creating turbulence) in the heat exchanger has a great influence on the heat exchange efficiency. is there. That is, when the heat medium flows through the heat transfer surface, the flow of the heat medium is made turbulent, whereby the heat exchange efficiency can be significantly improved. less than,
A specific method for causing the heat medium to be turbulent will be described based on examples. A second embodiment will be described with reference to FIG. The circular pipe 22 of the heat medium constituting the spiral element is made of copper, sand is filled in the circular pipe, and the roller is rolled while applying a load to the outer peripheral surface of the circular pipe. By rotating the circular tube while feeding it at a constant speed, a spiral groove as shown in FIG. 4 is formed. Spiral projections are formed on the inner surface of the circular tube. When the heat medium flows through this surface, the flow is disturbed by the projections, resulting in turbulent flow.

Further, a third embodiment will be described with reference to FIG. Heat medium circular tube 2 constituting spiral element
Instead of using the double tube 2, a spiral baffle plate as shown in FIG. 5 is inserted into the inner surface of the heat medium circular tube 22 instead of the inner tube 28. One side of the spiral baffle plate is the inlet side of the heat medium, and the other side is the outlet side (return side) of the heat medium. When a heat medium flows inside the spiral element configured as described above, the streamline of the heat medium is disturbed, and the film on the heat transfer surface is peeled off, resulting in a turbulent state.

Next, the transport efficiency in the hydrogen transport container will be described. By making the space excluding the volume of the buckle 12 from the internal volume of the hydrogen transport container 1 as small as possible, the entire hydrogen transport container can be made compact. In this embodiment, three buckles are inserted in the transport container. However, by increasing the number of buckles, the ratio of the volume of the buckle 12 to the entire volume of the hydrogen transport container can be increased. . Thus, the efficiency of transporting hydrogen can be improved.

Next, the effect of the spiral fin, which is one of the features of the present invention, will be described. The spiral fin is formed by fixing a metal (for example, copper alloy) plate having a high thermal conductivity spirally to the outer peripheral surface of the circular tube 22 constituting the spiral element 14. These fins are in the powder of the hydrogen storage alloy, and can have a large contact area with the hydrogen storage alloy. Although not shown, by further rotating the heat medium circular tube (adding a stirring function), a further improvement in heat exchange efficiency can be expected. On the other hand, when the fine powder hydrogen storage alloy is sealed in the buckle, the excellent effect that the fine powder can be easily filled in the closest packing by the screw effect of the spiral fin (the devolatilization effect by the screw indenting function) can be obtained. have.

Next, a method of replenishing the hydrogen supply tank with hydrogen, that is, a method of filling the hydrogen transport container with hydrogen from a hydrogen production base or a facility storing a large amount of hydrogen will be described.
When the hydrogen gas adjusted to 1 MPa is supplied from the hydrogen inlet / outlet hydrogen pipe 13 in a state where cold water of about 10 ° C. is flowed through the heat exchange spiral element 14 to cool the hydrogen storage alloy 15, the supplied hydrogen is It passes through the buckle setting plate 18 having the hydrogen passage hole and the cylindrical buckle 12 and is stored in the hydrogen storage alloy 15 as needed. At this time, the hydrogen storage alloy 13 is heated by the heat generated by the hydrogen storage alloy 15 storing the hydrogen, but the temperature is suppressed to 40 ° C. or lower by the cooling action of the spiral 14.

On the other hand, a method of supplying hydrogen from a hydrogen supply tank to a small-scale facility such as a hydrogen station, that is, a method of discharging hydrogen from a hydrogen transport container to a small-scale facility such as a hydrogen station will be described. Hot water of about 80 ° C. is passed through the spiral element 14 for heat exchange to heat the hydrogen storage alloy 15, thereby releasing hydrogen from the hydrogen storage alloy 15 and supplying the hydrogen from the hydrogen pipe 13 to the hydrogen station. At this time, hot water is supplied by a remote control flow control valve of a hot water outlet pipe 17 by a pressure sensor 20 of a hydrogen pipe 13 for inputting / outputting hydrogen via an external control panel so that the hydrogen release pressure becomes a constant value (0.2 MPa). Adjust the flow rate.

[0024]

As described above, according to the present invention, the hydrogen transport container of the present invention exhibits high heat transfer performance as a heat exchanger and can be reduced in weight and size. Further, when filling the closed space formed by the buckle and the circular tube with the hydrogen-absorbing alloy in the form of fine powder, the hydrogen-absorbing alloy can be easily and closely packed by rotating the circular tube. In addition, the value of the filtration area with respect to the amount of hydrogen storage alloy in one buckle is increased, so that it is safe against clogging of the filter, and the large hydrogen passage area allows the exothermic and endothermic reactions to proceed efficiently. I do. In addition, since various measures were taken to make the flow of the heat medium turbulent, the heat exchange efficiency between the hydrogen storage alloy and the heat medium was dramatically improved. Therefore, the time required for filling hydrogen into the hydrogen storage alloy and releasing hydrogen from the hydrogen storage alloy can be greatly reduced.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of a hydrogen transport container according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along the line AA in FIG.

FIG. 3 is an explanatory diagram of a configuration of a spiral element.

FIG. 4 is an embodiment in which a spiral projection is provided on the inner surface of the spiral element.

FIG. 5 is an explanatory view of a spiral baffle inserted into the inner surface of the spiral element.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Hydrogen transport container 11 Container (tank) 12 Buckle 13 Hydrogen pipe 14 Spiral element 15 Hydrogen storage alloy 16 Hot / cold water inlet pipe 17 Hot / cold water outlet pipe 18 Buckle installation plate 19 Temperature sensor 20 Pressure sensor 21 Spiral baffle plate 22 Heat medium Circular tube 23 Spiral fin 24 Hydrogen passage hole 25 Retention element 26 Base of buckle 27 Filter (ultra-tight filter cloth structure) 28 Inner tube

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) F28F 13/12 F28F 13/12 CF term (Reference) 3E072 EA10 GA30 3L103 AA05 AA37 AA39 BB50 CC02 CC35 DD08 DD10 DD19 DD36 DD38 DD44 DD63 4G040 AA14 AA24 AA32

Claims (3)

[Claims] 1. A hydrogen-transporting container using a hydrogen-absorbing alloy, comprising: a cylindrical buckle disposed in the container and comprising a plurality of outer-surface porous metal thin plates / inner-surface ultra-close-packed filter cloth structures; A spiral element provided concentrically in the buckle and having a spiral fin on the outer surface and a double pipe for passing hot and cold water for heat exchange on the inner surface; and the buckle and the spiral element. A hydrogen storage alloy in the form of a fine powder filled in a space, a temperature sensor for detecting a hydrogen temperature in the container, and a pressure sensor for detecting a hydrogen pressure in the container; container. 2. The hydrogen transport container according to claim 1, wherein a copper tube having a spiral projection on an inner surface is used as the spiral element. 3. The hydrogen transport container according to claim 1, wherein a copper tube having a spiral baffle on an inner surface is used as the spiral element.