JPH03290301A - Apparatus and method for controlling hydrogen concentration - Google Patents

Abstract

PURPOSE:To obtain a mixture gas containing hydrogen in a prescribed concentration by connecting a specified discharge line to a hydrogen occlusion unit communicating to a hydrogen-containing gas tank through the first pressure control valve. CONSTITUTION:Hydrogen is previously occluded in an alloy for hydrogen occlusion treated so as to occlude hydrogen at a prescribed temperature (Td) and pressure (Pb) and accommodated in a hydrogen occlusion unit 2. The inside of the unit 2 is heated to raise the temperature of the alloy to >=Td while watching a thermometer 2c and a plateau pressure corresponding to the temperature is realized. A preset pressure of the first pressure control valve 2d is set to a pressure free from an influence of pressure change in a hydrogen-containing tank 1 and a preset pressure of the second pressure control valve 4d is set to a pressure capable of introducing the hydrogen-containing gas into the unit 2 and some lower than in the valve 2d. The hydrogen-containing gas having a hydrogen concentration (Cs) is sent from the tank 1 to the unit 2 thereby and the hydrogen discharge pressure of the alloy is increased corresponding to the plateau pressure to discharge hydrogen. The hydrogen-containing gas having a hydrogen concentration higher than the hydrogen concentration (Ct) by a prescribed value is discharged to a product gas line 4 equipped with a flowmeter 4e and a hydrogen concentration detector 4b.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a hydrogen-accurate adjustment device and a hydrogen concentration adjustment method for obtaining a hydrogen mixed gas of a desired concentration from a hydrogen mixed gas.

(Prior Art) In equipment that utilizes excess hydrogen, such as in semiconductor fabrication processes, the excess hydrogen is burnt off or combined with oxygen using a catalyst and discarded as water.

(Problem to be Solved by the Invention) Conventionally, relatively high concentration hydrogen mixed gas containing impure gas was wasted. One of the problems of the present invention is to utilize such a hydrogen mixed gas as a desired low concentration hydrogen mixed gas, or to release it at a concentration that does not pose the risk of explosion, and another ill! The first method is to convert the relatively low-concentration hydrogen mixed gas that is wasted into a high-concentration hydrogen mixed gas.
” It is to plan for the purpose.

(Means for Solving the Problems) The present invention provides a pressure-composition isotherm [!] of a hydrogen storage alloy shown in FIG. This was done based on. When a hydrogen storage alloy absorbs hydrogen, while the solid solution phase changes to the hydride phase,
The pressure is approximately constant as a plateau pressure (hydrogen equilibrium pressure), and the hydrogen concentration increases.

Even when the hydrogen storage alloy releases hydrogen, the pressure in the hydride phase remains almost constant as the plateau pressure, and the hydrogen concentration decreases. As is known from the figure, in a hydrogen storage alloy treated to release hydrogen at a temperature Td and a pressure Pd, the concentration of occluded hydrogen increases at lower pressures as the temperature is lowered. That is, when the temperature T, (Td) decreases, the plateau pressure P (Pd) increases, and the hydrogen storage device of the hydrogen storage alloy increases, and the pressure of hydrogen gas that can exist in a gaseous state is Pl, so the supplied hydrogen The partial pressure of hydrogen in the mixed gas can be reduced to Pl, and the hydrogen obtained as a product gas is reduced according to P/Pb, and the product gas pressure is Fb. By adjusting the product gas pressure settings directly, a hydrogen mixed gas with the desired hydrogen & vCo reduced according to P/Pb can be obtained.Hydrogen is occluded at a temperature of 1JTd and a pressure of Pd. In the hydrogen storage alloy treated as above, the higher the temperature is raised, the lower the occluded hydrogen concentration becomes at high pressure.In other words, when the temperature is raised to T, ) Td, and the plateau pressure is P3).
As Pct increases, the hydrogen release pressure of the hydrogen storage alloy increases9.
Since the pressure of hydrogen gas that can exist in a gaseous state is P, the hydrogen partial pressure in the supplied hydrogen mixed gas can rise up to P3. The hydrogen concentration of the product gas obtained is determined by the product gas pressure P
o, it increases according to P1/P0. Therefore, by adjusting the plateau pressure set value and the product gas pressure set value, the desired hydrogen 11 degrees C0 can be adjusted to P, / P
An improved hydrogen mixed gas can be obtained depending on o.

For the above reasons, the first invention connects a hydrogen storage device including a hydrogen storage alloy, a heating/cooling device, and a thermometer to a hydrogen-containing gas tank via a first pressure control valve;
A hydrogen"!Ik variable adjustment device, in which a second pressure control valve, a product gas line equipped with a flow meter or a hydrogen concentration meter, and a discharge line equipped with a nine-hole valve are respectively connected to the hydrogen storage device. It is.

The second invention relates to a method for adjusting hydrogen concentration to a low concentration prize, and its configuration is as follows.

Hydrogen-containing gas tank K, predetermined temperature (Td), pressure (Pd
) A hydrogen storage device containing a hydrogen storage alloy that releases hydrogen gas and equipped with a heating/cooling device and a thermometer is connected via a first pressure control valve, and a second pressure control valve is connected to the hydrogen storage device. , a product gas line equipped with a flow meter or a hydrogen concentration meter, and a discharge line equipped with a gas pipe, respectively, to mix hydrogen at a relatively high hydrogen concentration (Cs) from the hydrogen-containing gas tank to the hydrogen storage device. supplying a gas and cooling the hydrogen storage alloy to a temperature lower than the temperature (Td);
The plateau pressure of the hydrogen storage alloy is lowered, and the set pressure of the second pressure control valve is set to a pressure slightly lower than the set pressure of the first pressure control valve, so that the pressure is lower than the hydrogen concentration (Cs) according to the plateau pressure. This is a hydrogen concentration adjustment method in which a hydrogen mixed gas with a predetermined low hydrogen concentration is sent to a product gas line.

The third invention relates to a method for adjusting hydrogen concentration to a high 11 degree hydrogen mixed gas, and the configuration thereof is as follows.

A hydrogen-containing gas tank is heated to a predetermined temperature (Td) and pressure (Pd).
), which has a built-in hydrogen storage alloy that stores hydrogen gas and is equipped with a heating/cooling device and a thermometer, is connected to the hydrogen storage device via a first pressure control valve, and a second pressure control valve is connected to the hydrogen storage device. A product gas line equipped with a valve and a flow meter or hydrogen concentration meter and a discharge line equipped with pulp are connected to supply a hydrogen mixed gas with a relatively low hydrogen concentration (Ct) from a hydrogen-containing gas tank to the hydrogen storage device. , in advance at a predetermined temperature (T
d) After storing hydrogen in the hydrogen storage alloy at a pressure (Pd), the hydrogen storage alloy is heated to a temperature higher than the above temperature (Td), and the plateau pressure of the hydrogen storage alloy is adjusted to a hydrogen concentration (C).
t), and the set pressure of the second pressure control valve is set to a pressure slightly lower than the set pressure of the first pressure control valve, and the hydrogen concentration is increased according to the plateau pressure. It(C
t) A hydrogen concentration adjustment method in which a predetermined high concentration hydrogen mixed gas is sent to the product gas line.

(Function) The water ),pressure(
When obtaining a high-concentration hydrogen mixed gas from a low-concentration hydrogen mixed gas by incorporating a hydrogen storage alloy that has been treated to release hydrogen gas using Pd)K, the predetermined temperature (Td) and pressure (Pd
) has a built-in hydrogen storage alloy that absorbs hydrogen gas.

Then, the hydrogen mixed gas is sent from the hydrogen-containing gas tank to the hydrogen storage device through the first pressure control valve, and the hydrogen storage alloy in the hydrogen storage device is heated to the desired temperature using the heating/cooling device, referring to the temperature of the thermometer. By heating or cooling to a desired temperature, the plateau pressure is set to a desired pressure, and hydrogen in the hydrogen mixed gas is stored or released in the hydrogen storage alloy according to the plateau pressure,
A high-concentration hydrogen mixed gas becomes a hydrogen mixed gas whose concentration has been reduced to the desired value, and in the case of a low-concentration hydrogen mixed gas, the hydrogen already stored in the hydrogen storage alloy is released to become a low-concentration hydrogen mixed gas. In addition, both gas mixtures are sent to the product gas line via the second pressure regulator, resulting in an enriched hydrogen gas mixture.

A flow meter or a hydrogen concentration meter detects a state in which a hydrogen storage alloy has sufficiently occluded hydrogen or released it into light as a change in flow rate or a change in hydrogen concentration.

The release line releases a hydrogen mixed gas consisting mainly of hydrogen stored and recovered in a hydrogen storage alloy from a high concentration hydrogen mixed gas, and the two discharge lines release a hydrogen mixed gas that is mainly composed of hydrogen stored and recovered from a hydrogen storage alloy from a high concentration hydrogen mixed gas. In addition, it is used to release hydrogen mixed gas mainly consisting of impure gas remaining in the hydrogen storage device.

Next, a case will be described in which the concentration of a high concentration hydrogen mixed gas is adjusted to a low concentration hydrogen mixed gas using this device.

The hydrogen absorption system/indoor containing the treated hydrogen storage alloy by releasing hydrogen at a predetermined temperature (Td) and pressure (Pd) is cooled with reference to a thermometer, and the temperature of the hydrogen storage alloy is measured.
- Cool to below the above temperature (Td), set the plateau pressure corresponding to the temperature, and set the set pressures of 1 pressure and 1 pressure to two pressures that are not affected by pressure fluctuations in the hydrogen-containing gas tank. The setting pressure of the second pressure control valve is set so that the hydrogen mixed gas can be introduced into the hydrogen absorbing lid, and the setting pressure of the first pressure system is also set slightly low. Then, a hydrogen mixed gas with a hydrogen concentration (C=) is supplied from the hydrogen-containing gas tank;! ? If the hydrogen partial pressure of hydrogen a degree (Cs) is higher than the above plateau pressure, the hydrogen in the hydrogen mixed gas will be transferred to the hydrogen storage alloy as the plateau pressure decreases. The hydrogen mixed gas, which is stored in the hydrogen gas and has a hydrogen concentration lower than that of the water bottle concentrated summer (Cs), is sent to the product gas line as a product gas.Then, the hydrogen storage alloy absorbs hydrogen into light components. Then, due to the increase in unoccluded hydrogen, the flow rate to the product gas line and the hydrogen fIk degree rapidly increase. Due to this phenomenon, it can be detected with a flow meter or hydrogen concentration meter and hydrogen absorption JI! Stop cooling the device and close both pressure control valves. In addition, the hydrogen concentration meter is
It is also used to set the set pressure of the second pressure control valve.

After completing hydrogen storage by the hydrogen storage alloy, the hydrogen storage device is switched to the heating state and the predetermined temperature (Td) and pressure (P
In step d), a hydrogen mixed gas containing mainly hydrogen is passed through the discharge line to recover hydrogen.

Next, a case will be described in which one device is used to adjust the concentration of a low concentration hydrogen mixed gas to a high concentration hydrogen mixed gas.

The hydrogen storage alloy in the hydrogen storage device, which contains a hydrogen storage alloy treated to store hydrogen at a predetermined temperature (Td) and pressure (Pd), is preliminarily stored with hydrogen as described later. The inside of the storage device is heated with reference to the temperature of the thermometer, the temperature of the hydrogen storage alloy is raised to the temperature (Td) or higher, the plateau pressure corresponding to the temperature is set, and the set pressure of the first pressure control valve is set to The pressure is set to a level that is not affected by pressure fluctuations in the hydrogen-containing gas tank, the second pressure control valve is set at a constant pressure that allows hydrogen mixed gas to be introduced into the hydrogen storage device, and the first pressure control valve is also set at a slightly lower pressure. Set up and hydrogen from hydrogen-containing gas tank! # degree (Ct) of hydrogen mixed gas is sent to the hydrogen storage device, the hydrogen release pressure of the hydrogen storage alloy increases according to the plateau pressure and releases hydrogen, and the released hydrogen is mixed with the hydrogen mixed gas. hydrogen Ik degree (Ct)
The hydrogen mixed gas increased by a predetermined value is sent to the product gas line as a product gas.

When the hydrogen storage alloy releases enough hydrogen, hydrogen is no longer released from the hydrogen storage alloy, and the flow rate and hydrogen concentration to the product gas line rapidly decrease. This detection is detected by a flow meter or a hydrogen concentration meter, the heating of the hydrogen storage device is stopped, and the meat pressure control valve is closed.

Note that the hydrogen concentration meter is also used to set the set pressure of the second pressure control valve.

After the hydrogen storage alloy has finished releasing hydrogen, the heating/cooling device is switched to cooling to cool the inside of the hydrogen storage device, and the hydrogen storage alloy is brought to a predetermined temperature (Td) and pressure (Pd), and the hydrogen-containing A hydrogen mixture gas is sent from the gas tank to cause the hydrogen storage alloy to absorb hydrogen.

After the suction is completed, a hydrogen mixed gas containing mainly impurity gas that is not ridged by the hydrogen storage alloy and remains in the hydrogen storage device is sent to the discharge line.

The hydrogen stored in the hydrogen storage alloy as described above is mixed into a low IIi hydrogen mixed gas by raising the greenhouse of the hydrogen storage alloy to a predetermined temperature (Td) or higher, as described above,
It can also be used as high-pressure, high-purity hydrogen gas.

(Example) An example of the hydrogen enrichment device according to the present invention will be described based on FIG. 1.

1 is a hydrogen-containing gas tank equipped with a first pressure gauge 1a and a first hydrogen concentration meter 15, and is capable of storing a high-concentration hydrogen mixed gas with a relatively high hydrogen concentration C3 or a low-concentration hydrogen mixed gas with a relatively low hydrogen concentration C1. Supply to outside.

21-1 is a hydrogen storage device equipped with a thermometer 2C, and is connected to the hydrogen-containing gas tank 1 via a first pressure control 92d. When processing a high-concentration hydrogen mixed gas, a hydrogen storage alloy that is processed to release hydrogen at a predetermined temperature Td and plateau pressure Pd (hydrogen equilibrium pressure) is incorporated. In addition, when processing a low Ik summer hydrogen mixed gas, a hydrogen storage device that is treated to store hydrogen at a predetermined @summer T and plateau pressure Pd and has a built-in washed hydrogen storage alloy is used. This is a 77II heat/cooling device that cools the hydrogen storage alloy in the hydrogen storage alloy when storing hydrogen and heats it when releasing hydrogen.

4 is connected to the hydrogen storage device 2 with a product gas line, a second pressure control tank 4d, a flow meter 4e, and a second hydrogen concentration meter 4b.

5 is a discharge line that processes high concentration hydrogen mixed gas and releases hydrogen after processing, or a discharge line that releases impure gas after processing low concentration hydrogen mixed gas, and hydrogen is absorbed through 1.5 lube 5f. It branches from between the device 2 and the second pressure control valve 4d and is connected to the hydrogen storage device 2.

6 is a control panel that controls each device.

Next, the action will be explained.

First, the case of obtaining a low-degree mixed gas from a high-concentration hydrogen mixed gas will be explained based on FIGS. 1 and 2.

The hydrogen storage device 2 is cooled by the heating/cooling device 3 with reference to the thermometer 2C, and the temperature of the hydrogen storage alloy is set to a temperature vT lower than the predetermined temperature Td at the time of hydrogen release.
The first pressure control valve 2dt sets the CsO high hydrogen concentration hydrogen mixed gas in the hydrogen-containing gas tank 1 to a pressure Pa that is not affected by pressure fluctuations in the hydrogen-containing gas tank 1.
- Hydrogen is supplied to the g & fumoto equipment 2 via. Then, the set pressure of the second pressure control valve 4d is set to a pressure Pb slightly lower than the pressure Pa to such an extent that the high degree mixed gas in the hydrogen-containing gas tank 1 can be introduced into the hydrogen storage device 2. The hydrogen mixed gas from is passed to the product gas line 4. Then, the hydrogen partial pressure of the hydrogen concentration (Cs) becomes the plateau pressure P
If it is higher than 1, the hydrogen in the high-concentration hydrogen mixed gas is stored in the hydrogen storage alloy, and the hydrogen mixed gas whose concentration is reduced according to P1/Pb as the hydrogen concentration C1 (see Figure 5) becomes the product. It flows as a gas to the product gas line 4.

If you are busy and want to obtain water x mixed gas with low hydrogen concentration, use KFi
, Hydrogen absorption R delusion! 2 is further cooled, and the temperature of the hydrogen storage alloy is lowered to a temperature T1 which is much lower.The plateau pressure is Pl) which is also lower P! If the purchased hydrogen gas with a high hydrogen concentration of CsO is introduced into the hydrogen storage bond 112 from the hydrogen-containing gas tank 1 without changing the set pressures of the first pressure control valve 2d and the second pressure control 3P4cl, the plateau pressure P,'/, the hydrogen absorption of the hydrogen storage alloy increases, and a large amount of hydrogen is stored in the hydrogen storage alloy, and the hydrogen concentration C1 becomes P
, /Pb, and the hydrogen mixed gas flows to the product gas line 4 as a product gas.

As shown in FIG. 5, time 1. When the hydrogen storage alloy has sufficiently occluded hydrogen and becomes difficult to occlude, the concentration of the hydrogen mixed gas flowing into the product gas line 4 increases and the flow t rapidly increases, va. Nagare violet meter 4e
The second pressure control valve 4d and the first pressure control valve 2 are inspected at
The increase in the hydrogen concentration in the product gas line 4 may be monitored using the second hydrogen concentration meter 4b while closing the gas line d. Thereafter, as shown in FIG. 2, the hydrogen storage alloy in the hydrogen storage device f2 is heated to a predetermined temperature using the heating/cooling device 3.
The hydrogen storage alloy is heated and raised to a plateau pressure Pd to put it in a hydrogen release state, and a hydrogen mixed gas containing mainly hydrogen gas is released to the release line 5 for hydrogen reuse. While the hydrogen storage device 2' is flowing the low-concentration hydrogen mixed gas to the product gas line 4, another hydrogen storage device 2 is being subjected to a hydrogen release process as shown in FIG. In addition, in FIG. 2, the valves shown in black (2d, 4d, 5f) are closed, and the valves shown in white (2d, 4d, 5f) are shown in an open state.

Next, low 1! The case of obtaining a highly concentrated hydrogen mixed gas from a highly concentrated hydrogen mixed gas will be explained based on FIGS. 1 and 3.

The hydrogen storage device 2 is heated by the heating/cooling device 3, and the hydrogen storage alloy is heated to a temperature T1 higher than the predetermined temperature Td during hydrogen storage and a plateau pressure P3 (see Fig. 4), and the hydrogen storage alloy is heated in the hydrogen-containing gas tank 1. A low concentration hydrogen mixed gas with a hydrogen concentration Ct of
It is supplied to the hydrogen storage device 2 via the first pressure control valve 2d, which is set to a pressure Pi that is not affected by pressure fluctuations in the hydrogen-containing gas tank 1. Then, the set pressure of the second pressure control valve 4d is set to a pressure P0 that is slightly lower than the pressure Pi when the low concentration hydrogen mixed gas in the hydrogen-containing gas tank 1 is introduced into the hydrogen storage device 2, and hydrogen storage is performed. When the hydrogen mixed gas is flowed from the device 2 to the product gas line 4, the hydrogen release pressure of the hydrogen storage alloy is increasing in accordance with the plateau pressure P. The hydrogen stored in the hydrogen storage alloy from the low-JI hydrogen mixed gas at a predetermined temperature Td and plateau pressure Pd is released into the hydrogen mixed gas, and hydrogen-4ge
As the hydrogen concentration Cs C is higher than t (see Figure 6), P,
The hydrogen mixed gas raised according to /P, ll flows to the product gas line 4 as a product gas.

If it is desired to obtain a hydrogen mixed gas with an even higher hydrogen concentration, the hydrogen storage alloy is brought into a state of a temperature iT4 higher than the temperature T, a plateau pressure P higher than the Rado pressure P, and the first
Hydrogen @Z is supplied from the hydrogen-containing gas tank 1 without particularly changing the set pressures of the pressure control valve 2d and the second pressure control yP4d.
If a low concentration hydrogen mixed gas of Ct is introduced into the hydrogen storage device 2, the hydrogen release pressure of the hydrogen storage alloy will further increase to the plateau pressure P4.
As the hydrogen concentration increases according to P4/P0, hydrogen is released from the hydrogen storage alloy more quickly and mixed with the low hydrogen mixed gas, and the mixed gas with increased concentration according to P4/P0 becomes the product gas as hydrogen concentration C4. Flows to product gas line 4.

Then, as shown in FIG. 6, time 1e? As time passes, the hydrogen storage alloy releases enough hydrogen and hydrogen becomes difficult to release, the concentration of the hydrogen mixed gas flowing to the product gas line 4 decreases and the flow rate decreases rapidly. is detected and the second pressure control fP4d and first pressure control valve 2d are closed. Alternatively, the decrease in water concentration may be detected by the second water accumulation 1# degree meter 4b.After that, as shown in FIG. 3, the hydrogen storage alloy in the hydrogen storage device 2 is heated and cooled 3, the temperature is cooled to a predetermined temperature Td, the plateau pressure is lowered to Pd, the hydrogen storage alloy is brought into a hydrogen storage state, and the hydrogen-containing gas tank 1 is
The lower concentration hydrogen gas is sent to the hydrogen storage capacity 2, and
After closing the pressure control valve 4d and the gas valve 5f to sufficiently store hydrogen, the pulp 5ft is momentarily opened to release a hydrogen mixed gas mainly containing the remaining impure gas to the discharge line 5.
Then, the hydrogen concentration increasing means described above is used. During this time, another hydrogen storage state 2' is low! I!
It is used to adjust the concentration of high-concentration hydrogen mixed gas to high-concentration hydrogen mixed gas.

Further, as described above, in a state where the hydrogen storage alloy in the hydrogen storage device 2 has sufficiently stored hydrogen, the first pressure control valve 2d,
If the second pressure control cell 4d and the pulp 5f are closed and the temperature of the hydrogen storage alloy is raised to T, then it is released from the product gas line 4, the hydrogen concentration and product gas pressure can also be increased.

FIG. 7 (al, (bl, (C1 and fdl)) The device according to the present invention is applied to a pair of hydrogen-containing gas tanks 1, 1' and a pair of hydrogen storage devices 2, 2', and both hydrogen-containing gas tanks 1 and 2' are This figure shows the handling of each valve in several cases in which a high concentration hydrogen mixed gas is obtained by supplying a low concentration hydrogen mixed gas from .1' to each of the hydrogen storage devices 2 and 2'. indicates the same part, and each 2d/ corresponds to the first pressure control valve 2d.The valves shown in black are closed, and the valves shown in white are open. Both pulps 5f are opened instantaneously when hydrogen mixed gas containing a large amount of impure gas is flowed to the gas discharge line 5 after each hydrogen storage device 2, 2' has sufficiently stored hydrogen. (T,) is
Heating/cooling device 3.3' Hydrogen absorption device-12,2'
Indicates the temperature inside.

Figure (al) shows that the hydrogen &lE device 2 is accumulatively occluding in the hydrogen-containing gas tank 1'nig 7, and the hydrogen storage device 2' is pre-occluding the low-strength hydrogen mixed gas introduced from the hydrogen-containing gas tank 1. This shows a case in which the hydrogen that had been stored is released, the hydrogen concentration is completely increased, and the hydrogen is sent to the product gas line 4.

Figure (b) shows that the hydrogen storage device 2 is connected to the hydrogen-containing gas tank 1.
A case is shown in which the hydrogen stored from the hydrogen storage device 2' is stored from the hydrogen-containing gas tank 1 by sending the stored hydrogen to the product gas line 4.

The figure (Cl) shows a case where the hydrogen storage device: IL2 stores hydrogen from the hydrogen-containing gas tank 1', and the hydrogen absorber f2' sends the stored hydrogen to the product gas line 4.

Figure (a) shows a case where the hydrogen storage state 2 stores hydrogen from the hydrogen-containing gas tank 1, and the hydrogen storage 11' absorbs hydrogen from the hydrogen-containing gas tank 1'.

(Effects of the Invention) Two things can be understood from the above explanation: According to the invention, a desired low-concentration hydrogen mixed gas is superior to a high-concentration hydrogen-superior hydrogen mixed gas, and also contains low-concentration hydrogen. Desired from water x mixed gas. a Hydrogen mixed gas at 1 degree C and high pressure is obtained. Therefore, by incorporating this cliff into the hydrogen release system, the hydrogen concentration can be reduced to a safe concentration and released into the atmosphere, and the hydrogen stored in the hydrogen storage alloy can be recovered. Moreover, a low concentration, low pressure hydrogen mixed gas can be reused as a high concentration, high pressure hydrogen mixed gas.

Specifically, it can be used as an atmospheric gas supply device for an atmosphere firing furnace to supply hydrogen with its concentration fully adjusted, or it can be used to recover hydrogen from the gas released from the atmosphere firing furnace.

[Brief explanation of drawings]

Fig. 1 is an equipment layout diagram showing an embodiment of the hydrogen concentration adjusting device according to the present invention, Fig. 2 is an explanatory diagram of the operation when adjusting a high concentration hydrogen mixed gas to a low concentration hydrogen mixed gas, and Fig. 3 teeth,
An explanatory diagram of the effect when adjusting a low concentration hydrogen mixed gas to a high concentration hydrogen mixed gas, Fig. 4 is a pressure-composition isothermal curve diagram of a hydrogen storage alloy, and Fig. 5 is a diagram from a high concentration hydrogen mixed gas according to an example. A diagram showing the relationship between the elapse of time and the hydrogen concentration of the product gas when adjusting to a low concentration hydrogen mixed gas, Figure 6 shows the time elapse when adjusting to a higher concentration hydrogen gas than the low concentration hydrogen mixed gas according to the example Figure 7 (al, (bl, (C), (d)) shows the relationship between hydrogen concentration and product gas hydrogen concentration, respectively. 1, 1': Hydrogen-containing gas tank, 1a: Pressure gauge, 1
b: First hydrogen concentration meter, 2, 2': Hydrogen absorption device, 2
d, 2a': first pressure control valve, 2C: @ positioning needle, 3': heating/cooling device, 4: product gas line, : second hydrogen concentration meter, 4d: second pressure control beak valve, second flow 1 meter, 5: Release line,
5f: Nonorubu.

Claims (3)

[Claims] (1) A hydrogen storage alloy is built into the hydrogen-containing gas tank,
The first hydrogen storage device is equipped with a heating/cooling device and a thermometer.
A second pressure control valve and a product gas line with a flow meter or a hydrogen concentration meter and a discharge line with pulp are connected to the hydrogen storage device through a pressure control valve, respectively. Hydrogen concentration adjustment device. (2) A hydrogen storage alloy that releases hydrogen gas at a predetermined temperature (Td) and pressure (Pd) is built into the hydrogen-containing gas tank, and the hydrogen storage device equipped with a heating/cooling device and a thermometer is controlled by the first pressure control. A second valve is connected to the hydrogen storage device via a valve.
connecting a product gas line with a pressure control valve and a flow meter or a hydrogen concentration meter and a discharge line with a pulp, respectively, from the hydrogen-containing gas tank to the hydrogen storage device;
Supplying a hydrogen mixed gas with a relatively high hydrogen concentration (Cs),
Cooling the hydrogen storage alloy to a temperature lower than the temperature (Td), reducing the plateau pressure of the hydrogen storage alloy, and setting the set pressure of the second pressure control valve to a pressure slightly lower than the set pressure of the first pressure control valve. The hydrogen concentration (Cs
) A hydrogen concentration adjustment method characterized by sending a hydrogen mixed gas having a lower predetermined low hydrogen concentration to a product gas line. (3) A hydrogen storage alloy that stores hydrogen gas at a predetermined temperature (Td) and pressure (Pd) is built into the hydrogen-containing gas tank, and the hydrogen storage device equipped with a heating/cooling device and a thermometer is controlled by the first pressure. A second pressure control valve and a product gas line with a flow meter or a hydrogen concentration meter and a discharge line with pulp are connected to the hydrogen storage device through a valve, and a discharge line with a pulp is connected to the hydrogen storage device from a hydrogen-containing gas tank. After supplying a hydrogen mixed gas with a relatively low hydrogen concentration (Ct) to the hydrogen storage alloy and storing hydrogen in advance at a predetermined temperature (Td) and pressure (Pd), the hydrogen storage alloy is heated to a temperature higher than the temperature (Td). The hydrogen storage alloy is heated to , and the hydrogen concentration (
The set pressure of the second pressure control valve is set to a pressure slightly lower than the set pressure of the first pressure control valve, and the hydrogen concentration (Ct) is increased according to the plateau pressure.
) A hydrogen concentration investigation method characterized by sending a hydrogen mixed gas with a predetermined high concentration to a product gas line.