JPH11101729A - Apparatus for measuring reaction speed of hydrogen-storing alloy - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the influence of a pressure change consequent to a temperature change and enable highly accurate measurement by respectively providing a part of a measuring system with an accumulator of a large capacity and a buffer tank with a temperature stabilization means. SOLUTION: A testing apparatus is arranged inside a thermostat 3. A sample container 1 of high-conductivity metal having a filter 2 of small pressure loss built therein, a large-capacity accumulator 4, a highly accurate pressure gauge 5, a relief valve 6, a buffer tank 8 and a highly accurate differential pressure gauge 9 are connected via an opening valve 7 of good response and small flow resistance. The accumulator 4 and buffer tank 8 are incorporated in a heat insulation chamber 10. In this constitution, an initial pressure is measured by the pressure gauge 5, and a change of a hydrogen pressure while a reaction speed is measured is obtained by recording a differential pressure of the buffer tank 8 and accumulator 4 by the differential pressure gauge 9. At this time, in order to prevent an internal pressure of the buffer tank 8 and accumulator 4 from being changed because of a temperature change, the buffer tank 8 and accumulator 4 are thermally insulated in the heat insulation chamber 10.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for measuring a reaction rate of a hydrogen storage alloy for measuring a reaction rate, which is one of the characteristics evaluation of the hydrogen storage alloy.

[0002]

2. Description of the Related Art A method for measuring the reaction rate of a hydrogen storage alloy is specified by Japanese Industrial Standards (JIS H7).
202 Hydrogen storage alloy hydrogenation rate test method). This J
Fig. 3 shows the basic configuration of the test equipment specified in ISH7202.
Shown in The test apparatus is placed in a thermostat 33 having good temperature control performance, and has a metal sample container 21 having a high thermal conductivity and a built-in filter 22 having a small pressure loss; This is a Siebeltz apparatus in which an accurate pressure gauge 25 and a relief valve 26 are connected via an opening / closing valve 27 having good responsiveness and low flow resistance. The reaction rate is measured by recording the time change of the hydrogen pressure with the pressure gauge 25 by the Siebert's (capacity) method.

[0003] The above reaction rate is measured by Sibeltz (volume).
Because of this method, there is a certain difference between the initial pressure and the final pressure, and the conditions change between the initial and final pressures. Therefore, in order to further reduce the amount of change, a reaction rate measuring device including a differential pressure gauge for increasing the capacity of the pressure accumulator and accurately measuring the reduced amount of change has been proposed.

[0004]

However, in a conventional reaction rate measuring device having a large-capacity accumulator and a differential pressure gauge, the change in the hydrogen pressure due to the temperature of the accumulator and the like is small because the change in the hydrogen pressure is small. There is a problem that the influence of the influence is relatively large. As a countermeasure, a method of performing temperature correction by performing measurement with a temperature sensor is generally considered, but a high-precision temperature sensor is required, and it is difficult to measure the temperature distribution accurately. Is not working well. Further, when the buffer tank changes from the initial pressure, the relationship between the differential pressure of hydrogen measured by the differential pressure gauge and the absolute pressure is broken, and there is a problem that the accuracy of the differential pressure gauge cannot be utilized.

Further, since a large-capacity accumulator is used, there is a problem that a large amount of hydrogen is used for measurement and the hydrogen must be exhausted wastefully.

The present invention has been made in view of the above-mentioned conventional problems, and is intended to reduce the influence of a pressure change due to a temperature change so as to be able to measure with high accuracy and to recover the discharged hydrogen. It is intended to provide.

[0007]

According to the present invention, there is provided an apparatus for measuring a reaction rate of a hydrogen storage alloy, comprising: a sample container disposed in a thermostat;
Hydrogen that is formed by connecting an accumulator, a buffer tank, and a differential pressure gauge via an open / close valve, and introduces the initial hydrogen pressure into the buffer tank to measure the differential pressure from the hydrogen pressure being measured by the differential pressure gauge. In an apparatus for measuring the reaction rate of an occlusion alloy, at least a part of a measurement system, particularly, a large-capacity accumulator and a buffer tank are provided with temperature stabilizing means. Even with a large capacity, the effect of pressure changes due to temperature changes can be reduced, and high-accuracy measurement can be realized.

[0008] Further, a hydrogen storage tank for recovering discharged hydrogen, preferably a hydrogen storage tank container for recovering discharged hydrogen, which is preferably a container containing a hydrogen storage alloy, is provided, and the discharged hydrogen can be recovered. When a container containing a hydrogen storage alloy is used, a large amount of hydrogen can be recovered with a compact configuration.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the apparatus for measuring the reaction rate of a hydrogen storage alloy according to the present invention will be described below with reference to FIGS.

(First Embodiment) In FIG. 1, a test apparatus is disposed in a thermostat 3 and has a filter 2 having a small pressure loss.
, A high-conductivity metal sample container 1 having a high thermal conductivity, a large-capacity pressure accumulator 4, a high-precision pressure gauge 5, a relief valve 6, a buffer tank 8, and a high-precision differential pressure gauge 9 This is a Siebeltz device connected via an open / close valve 7 having good flow resistance and low flow resistance. Further, the pressure accumulator 4 and the buffer tank 8 are built in the heat retaining chamber 10.

At the time of setting the initial pressure for measuring the reaction rate, the initial pressure is measured by the pressure gauge 5 and the initial pressure is measured.
The change in the hydrogen pressure during the measurement of the reaction rate is performed by recording the differential pressure between the buffer tank 8 and the accumulator 4 with the differential pressure gauge 9.

At this time, the temperature of the buffer tank 8 and the pressure accumulator 4 is maintained in the heat retaining chamber 10 in order to prevent the internal pressure from changing due to a change in temperature such as room temperature. For this reason, the pressure in the buffer tank 8 is kept constant, and the change in the hydrogen pressure in the accumulator 4 is only due to the hydrogen that has reacted with the hydrogen storage alloy (not shown) in the sample container 1. it can.

In this embodiment, the temperature maintaining means 10 is used as the temperature stabilizing means. However, other temperature stabilizing means such as a heat insulating material and a heater, or a thermostat may be used. Further, only the accumulator 4 and the buffer tank 8 are kept at a constant temperature in the heat retaining chamber 10, but such a temperature stabilizing means may be provided in a part or all of other measurement system piping.

(Second Embodiment) In FIG. 2, the same components as those described with reference to FIG. 1 are denoted by the same reference numerals, and description thereof is omitted. In this embodiment, a hydrogen storage tank 11 containing a hydrogen storage alloy 12 having a low equilibrium hydrogen pressure is connected via a three-way cock 13 to a pipe section before being connected to a vacuum pump.

When the dehydrogenation reaction is measured after measuring the hydrogen reaction rate, the hydrogen in the accumulator 4 and the buffer tank 8 is discharged out of the system in order to obtain a predetermined pressure (often atmospheric pressure). There must be. Further, when activating the sample, it is necessary to release hydrogen in the pressure accumulator 4, the buffer tank 8, and the piping system of the apparatus. The amount of released hydrogen is enormous because the pressure accumulator 4 has a large capacity.

Therefore, in this embodiment, the three-way cock 13 is operated to store the released hydrogen in the hydrogen storage tank 11 containing the hydrogen storage alloy 12 having a low equilibrium hydrogen pressure.

The stored hydrogen is supplied to a hydrogen storage tank 11
May be heated with a heater or hot water to raise the equilibrium hydrogen pressure of the hydrogen storage alloy and returned to the piping system such as the pressure accumulator 4 when measuring the hydrogenation reaction rate, or a separate pipe may be installed to install a hydrogen burner or fuel cell. It may be used for other purposes.

In the present embodiment, a vessel containing a hydrogen storage alloy 12 is used as the hydrogen storage tank 11 for recovering the discharged hydrogen, but another vessel using a hydrogen absorbing material or a large capacity cylinder is used. A hydrogen storage tank may be used.

[0019]

According to the apparatus for measuring the reaction rate of a hydrogen storage alloy according to the present invention, as is apparent from the above description, the sample container, the accumulator, the buffer tank and the differential pressure gauge arranged in the thermostatic chamber are opened and closed. In the reaction rate measuring device of the hydrogen storage alloy, the hydrogen pressure in the initial stage of the measurement is introduced into the buffer tank, and the differential pressure from the hydrogen pressure during the measurement is measured by the differential pressure gauge. Temperature stabilizing means in at least a part of the pressure accumulator and the buffer tank, especially the large capacity, so that even if the accumulator has a large capacity in order to reduce the pressure change during the measurement, the effect of the pressure change due to the temperature change Can be reduced and highly accurate measurement can be realized.

Further, since a hydrogen storage tank for recovering discharged hydrogen, preferably a hydrogen storage tank container for recovering discharged hydrogen comprising a container containing a hydrogen storage alloy is provided, the discharged hydrogen can be recovered, and When a container containing a hydrogen storage alloy is used, a large amount of hydrogen can be recovered with a compact configuration.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a first embodiment of a reaction rate measuring device for a hydrogen storage alloy according to the present invention.

FIG. 2 is a configuration diagram of a second embodiment of the hydrogen storage alloy reaction rate measuring device of the present invention.

FIG. 3 is a configuration diagram of a conventional hydrogen storage alloy reaction rate measuring device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Sample container 3 Thermostat 4 Pressure accumulator 7 Open / close valve 8 Buffer tank 9 Differential pressure gauge 10 Heat insulation chamber (temperature stabilization means) 11 Hydrogen storage tank 12 Hydrogen storage alloy

Claims (4)

[Claims] 1. A system comprising a sample container, an accumulator, a buffer tank and a differential pressure gauge arranged in a thermostat, connected via an opening / closing valve to introduce a hydrogen pressure at an initial stage of the measurement into the buffer tank and measure the hydrogen pressure during the measurement. A reaction rate measuring device for a hydrogen storage alloy, wherein a temperature stabilizing means is provided in at least a part of a measuring system in a reaction rate measuring device for a hydrogen storage alloy, wherein a pressure difference from a pressure is measured by a differential pressure gauge. apparatus. 2. The hydrogen storage alloy reaction rate measuring device according to claim 1, wherein a temperature stabilizing means is provided in the pressure accumulator and the buffer tank. 3. A method of connecting a sample container, an accumulator, a buffer tank, and a differential pressure gauge arranged in a thermostat via an opening / closing valve to introduce a hydrogen pressure at an initial stage of the measurement into the buffer tank to measure the hydrogen during the measurement. What is claimed is: 1. A hydrogen storage alloy reaction rate measuring apparatus, comprising: a hydrogen storage tank for recovering discharged hydrogen, wherein the hydrogen storage alloy reaction rate measuring apparatus is configured to measure a pressure difference from a pressure with a differential pressure gauge. 4. The hydrogen storage alloy reaction rate measuring device according to claim 3, wherein the hydrogen storage tank is a vessel containing a hydrogen storage alloy for recovering discharged hydrogen.