JP2022103999A - Treatment gas adjusting device, treatment gas adjusting method, and system for manufacturing metal hydride - Google Patents

Abstract

To provide a device and a method that suppress deterioration of purity of hydrogen of a treatment gas in a chamber when producing a metal hydride.SOLUTION: A treatment gas adjusting device is connected to a device for manufacturing a metal hydride by making a hydrogen plasma generated in a chamber in an atmosphere using a supplied hydrogen gas as a treatment gas act on a metal powder in the chamber and is designed to adjust the purity of the hydrogen of the treatment gas. The treatment gas adjusting device comprises a circulation line that returns the treatment gas delivered from the chamber to the chamber, a pump that is provided in the circulation line and pressure-feeds the treatment gas, and an air dryer that is provided in the circulation line so as to be positioned on the upstream side of the pump and removes water contained in the treatment gas.SELECTED DRAWING: Figure 2

Description

The present disclosure relates to a processing gas adjusting device, a processing gas adjusting method, and a system for producing a metal hydride.

Patent Document 1 discloses a method for producing magnesium hydride. In this production method, magnesium oxide is used as a raw material for magnesium hydride as an example. The raw material contained in the chamber in the hydrogen atmosphere is irradiated with hydrogen plasma. In the chamber, an adhering means having a surface having a surface below the precipitation temperature of magnesium hydride is arranged. Magnesium hydride is deposited on the surface of the adhering means and recovered.

Japanese Unexamined Patent Publication No. 2018-203607

Since hydrogen gas is used in the production of magnesium hydride in the method described in Patent Document 1, the oxygen atom remaining in the chamber or the oxygen atom contained in the raw material is combined with hydrogen to generate water. There is. In this case, the inside of the chamber has an atmosphere in which hydrogen gas and water vapor are mixed. Therefore, in the method described in Patent Document 1, the purity of hydrogen in the processing gas in the chamber may decrease, and stable hydrogen plasma may not be generated. The present disclosure provides a technique capable of suppressing a decrease in the purity of hydrogen in a processing gas in a chamber when producing a metal hydride.

One aspect of the present disclosure is a treated gas regulator. This processing gas regulator is connected to a device that produces metal hydrides. The device for producing a metal hydride causes a hydrogen plasma to act on a metal powder in a chamber to produce a metal hydride. Hydrogen plasma is generated in a chamber in an atmosphere using the supplied hydrogen gas as a processing gas. The processing gas adjusting device adjusts the purity of hydrogen in the processing gas. The processing gas regulator is equipped with a circulation line, a pump and an air dryer. The circulation line returns the processing gas delivered from the chamber to the chamber. The pump is installed in the circulation line and pumps the processing gas. The air dryer is provided in the circulation line so as to be located on the upstream side of the pump, and removes the water contained in the processing gas.

According to the processing gas adjusting device according to one aspect of the present disclosure, the processing gas in the chamber is sent to the circulation line, water is removed by the air dryer provided in the circulation line, and the processing gas is returned to the chamber again. Therefore, according to this processing gas adjusting device, it is possible to suppress a decrease in the purity of hydrogen in the processing gas in the chamber when the metal hydride is produced.

In one embodiment, the treated gas regulator may include a tank for storing a liquid through which the treated gas passes. This tank is installed in the circulation line so as to be located on the upstream side of the air dryer. In this case, the processing gas is cooled as it passes through the liquid, and the water vapor in the processing gas returns to water and is trapped in the liquid. Further, the processing gas may also contain a metal powder as a raw material and a by-product during plasma generation. As the processing gas passes through the liquid, these by-products and the like are also trapped in the liquid. This prevents the metal powder of the raw material and the by-products during plasma generation from reaching the pump. Therefore, wear and malfunction of pump parts and dust explosion of metal powder are avoided. Therefore, according to this processing gas adjusting device, it is possible to further suppress the decrease in the purity of hydrogen in the processing gas in the chamber when producing the metal hydride, and it is possible to improve the safety while avoiding the pump failure. ..

In one embodiment, the processing gas regulator may include a discharge mechanism for discharging the liquid from the tank. In this case, the processing gas regulator can recover and reuse the metal powder trapped in the liquid and the by-products during plasma generation.

In one embodiment, the treated gas regulator may be provided on the circulation line so as to be located upstream of the tank and may include a check valve to prevent backflow of the treated gas from the tank to the chamber. In this case, the processing gas regulator can prevent the liquid in the tank from flowing back into the chamber.

In one embodiment, the processing gas regulator may be provided on the circulation line so as to be located downstream of the pump and may include a regulating valve that regulates the flow rate of the treated gas returned to the chamber. In this case, the processing gas adjusting device can adjust the flow rates of the processing gas sent to the chamber and the processing gas drawn from the chamber.

In one embodiment, the processing gas regulator may include a branch line and a switching valve. The branch line is connected to the circulation line on the downstream side of the regulating valve, and connects the circulation line to the outside of the device. The switching valve switches the flow of processing gas between the circulation line and the branch line. In this case, by operating the switching valve, either circulation of the processing gas or discharge of the processing gas to the outside is selected. As a result, the processing gas regulator, for example, when the purity of hydrogen in the processing gas deviates significantly from the set value, the processing gas in the chamber is exhausted from the branch line while supplying new hydrogen gas to the chamber. The processing gas in the chamber can be replaced.

In one embodiment, the switching valve may include a first on-off valve provided on the circulation line and a second on-off valve provided on the branch line. The first on-off valve is provided so as to be located on the downstream side of the connection point between the circulation line and the branch line. In this case, the processing gas adjusting device can stop the function of the circulation line without stopping the pump by providing the first on-off valve and the second on-off valve.

Another aspect of the present disclosure is the treated gas conditioning method. This processing gas adjusting method adjusts the purity of hydrogen in the processing gas in the method for producing a metal hydride. In the production method, hydrogen plasma is allowed to act on the metal powder in the chamber to produce a metal hydride. Hydrogen plasma is generated in a chamber in an atmosphere using the supplied hydrogen gas as a processing gas. The processing gas adjusting method includes the following steps.
(1) A process of sending the processing gas from the chamber to the circulation line.
(2) A step of passing the processing gas through an air dryer provided in the circulation line to remove water contained in the processing gas.
(3) A step of returning the processing gas that has passed through the air dryer to the chamber using a pump.

Yet another aspect of the present disclosure is a system for producing metal hydrides. The system includes a chamber, a gas supply device, a plasma generator, an exhaust system, a circulation line, a pump, and an air dryer. The chamber houses the metal powder. The gas supply device supplies hydrogen gas to the chamber as a processing gas. The plasma generator generates hydrogen plasma in a chamber in a hydrogen atmosphere. The exhaust device decompresses the inside of the chamber. The circulation line returns the processing gas delivered from the chamber to the chamber. The pump is installed in the circulation line and pumps the processing gas. The air dryer is provided in the circulation line so as to be located on the upstream side of the pump, and removes the water contained in the processing gas.

The processing gas adjusting method and the system for producing the metal hydroxide have the same effect as the above-mentioned processing gas adjusting device.

According to the present disclosure, it is possible to suppress a decrease in the purity of hydrogen in the processing gas in the chamber when producing a metal hydride.

It is a schematic diagram which shows an example of the system which manufactures a metal hydride which concerns on embodiment. It is a schematic diagram which shows an example of the processing gas adjustment device of FIG. It is a flowchart which shows the method of manufacturing a metal hydride. It is a flowchart which shows the processing gas adjustment method which concerns on embodiment.

Hereinafter, various embodiments will be described in detail with reference to the drawings. The same reference numerals are given to the same or corresponding parts in each drawing.

[System for manufacturing metal hydrides]
FIG. 1 is a schematic diagram showing an example of a system for producing a metal hydride according to an embodiment. The system 100 shown in FIG. 1 causes a hydrogen plasma to act on a metal powder to produce a metal hydride.

The metal powder is, for example, a magnesium-based powder. The magnesium-based powder is, for example, a powder of magnesium, magnesium oxide, magnesium hydroxide, or the like. An example of a metal hydride produced by allowing hydrogen plasma to act on a magnesium-based powder is magnesium hydride. The metal powder may be sodium or borate powder. The borate is, for example, metaborate, tetraborate, or pentaborate. The metaborate is, for example, NaBO ₂ , KBO ₂ , LiBO ₂ , Ca (BO ₂ ) ₂ , or Mg (BO ₂ ) ₂ . The tetraborate is, for example, Na ₂ B ₄ O ₇ , Na ₂ O · 2 BO ₃ , K ₂ O · B ₂ O ₃ , Li ₂ B ₄ O ₇ , or Mg ₃ B ₄ O ₉ . The pentaborate is, for example, NaB ₅ O ₈ , Na ₂ O ・ 5B ₂ O ₃ , KB ₅ O ₈ , K ₂ O ・ 5B ₂ O ₉ , or LiB ₅ O ₈ . Boron is a natural boron mineral, Na ₂ B ₄ O ₇・ 10H ₂ O, Na ₂ B ₄ O ₇・ 4H ₂ O, Ca ₂ B ₆ O _{11.5H 2} O, CaNaB ₅ O _{9.6H 2} O, Mg ₇ Cl ₂ B ₁₇ O ₃₀ and the like may be used. Sodium metaborate (NaBO ₂ ) may be selected as the borate from the above-mentioned examples from the viewpoints of availability, acquisition cost, chemical stability, ease of hydrogen desorption, hydrogen storage density, and the like. An example of a metal hydride produced by allowing hydrogen plasma to act on a magnesium-based powder is tetrahydroborate. The metal powder may be a mixture of a magnesium-based powder and a sodium or borate powder.

As shown in FIG. 1, the system 100 includes a chamber 10 in which a processing space is defined. The sample holder 11 is housed inside the chamber 10. The sample holder 11 supports the metal powder S. A vibration generator 14 is connected to the sample holder 11. The vibration generator 14 applies vibration to the sample holder 11 to cause the metal powder S in the sample holder 11 to flow. A vacuum pump 16 (an example of an exhaust device) is connected to the chamber 10 via a pipe 15. The vacuum pump 16 decompresses the inside of the chamber 10 and adjusts it to a predetermined pressure.

A hydrogen gas cylinder 30 is connected to the chamber 10 via a pipe 42. The hydrogen gas cylinder 30 supplies hydrogen gas to the inside of the chamber 10 via the pipe 42. That is, the hydrogen gas cylinder 30 and the pipe 42 function as an example of the gas supply device. The hydrogen gas supplied to the inside of the chamber 10 is used as a processing gas. The processing gas is a gas for exciting plasma. By supplying hydrogen gas from the hydrogen gas cylinder 30 to the chamber 10, the inside of the chamber 10 becomes a hydrogen atmosphere. Other gas sources such as a nitrogen gas cylinder 31 for purging, a hydrogen compound gas cylinder 32, and the like may be connected to the chamber 10 via a pipe 42.

A microwave generation mechanism 18 (an example of a plasma generator) that outputs microwaves for exciting the processing gas supplied into the chamber 10 is connected to the chamber 10 via a flexible coaxial waveguide 40. The microwave generation mechanism 18 includes a microwave oscillator 20, an isolator 21, a power monitor 22, a tuner 23, and a rectangular coaxial waveguide converter 24. The microwave oscillator 20 generates microwaves having a predetermined frequency, power and bandwidth. The isolator 21 limits the propagation direction of the microwave and propagates the microwave to the chamber 10. The power monitor 22 monitors the traveling wave power and the reflected wave power of the microwave and feeds them back to the microwave oscillator 20. The tuner 23 is provided in a waveguide in which microwaves travel, and is adjusted so that the impedances of the chamber 10 and the microwave generation mechanism 18 are matched. The rectangular coaxial waveguide transducer 24 converts the microwave mode and transmits the microwave to the antenna provided in the upper part of the chamber 10.

A quartz plate 41 capable of propagating microwaves while shielding the atmosphere is provided on the ceiling of the chamber 10, that is, below the antenna. The quartz plate 41 is formed of, for example, a dielectric and functions as a window member for introducing microwaves into the chamber. In the chamber 10, the supplied processing gas is depressurized to a predetermined pressure, and the electrons accelerated by the microwave electric field collide with the molecules of the processing gas (here, hydrogen molecules) and are ionized to generate hydrogen plasma P. do. As a result, the metal powder is plasma-treated to obtain a metal hydride. As an example, the reaction represented by the reaction formula (1) when the metal powder is magnesium oxide, the reaction formula (2) when the metal powder is magnesium hydroxide, and the reaction formula (3) when the metal powder is sodium metaborate. Therefore, a metallic hydrate is obtained.
MgO + 3H ₂ → MgH ₂ + 2H ₂ O (1)
Mg (OH) ₂ + 2H ₂ → MgH ₂ + 2H ₂ O (2)
NaBO ₂ + 4H ₂ → NaBH ₄ + 2H ₂ O (3)

Water is produced in any of the reaction formulas (1) to (3). In this case, since water vapor is mixed with the hydrogen atmosphere of the chamber 10, the purity of hydrogen in the processing gas is lowered. Therefore, a processing gas adjusting device 50 for adjusting the hydrogen purity of the processing gas is connected to the chamber 10.

[Processing gas regulator]
FIG. 2 is a schematic diagram showing an example of the processing gas adjusting device of FIG. As shown in FIG. 2, the processing gas adjusting device 50 includes a circulation line 51. The chamber 10 is formed with an inlet 10a and an inlet 10b that communicate with the inside of the chamber 10. The circulation line 51 is a pipeline connected to the inlet 10a and the inlet 10b, through which the processing gas discharged from the chamber 10 is circulated and returned to the chamber 10.

The circulation line 51 is provided with a check valve 52, a tank 53, an air dryer 55, a pump 56, a regulating valve 57, and a first on-off valve 58 (an example of a switching valve) along the flow direction of the processing gas. The processing gas delivered from the delivery port 10a of the chamber 10 first reaches the check valve 52.

The check valve 52 is a valve that controls the flow of the processing gas in one direction. The check valve 52 prevents the backflow of the processing gas from the tank 53 to the chamber 10 while allowing the processing gas sent out from the delivery port 10a of the chamber 10 to flow to the tank 53. The processing gas that has passed through the check valve 52 is sent to the tank 53.

The tank 53 is provided in the circulation line 51 so as to be located on the downstream side of the check valve 52. The tank 53 is a container for storing a liquid through which the processing gas passes. Water is stored in the tank 53 as an example. The stored liquid is used to bubbling the processing gas. That is, the processing gas that has passed through the check valve 52 is passed through the liquid stored in the tank 53. Water vapor, metal powder, and by-products of plasma treatment contained in the treatment gas are trapped in the liquid. The tank 53 may be provided with a drain valve 54 (an example of a discharge mechanism) for discharging the liquid from the tank 53. The liquid discharged through the drain valve 54 is recovered, and the metal powder or by-products contained in the liquid is recovered and reused. The processing gas that has passed through the tank 53 is sent to the air dryer 55.

The air dryer 55 is provided on the circulation line 51 so as to be located on the downstream side of the tank 53. The air dryer 55 removes water contained in the processing gas. The air dryer 55 may be of any of a freezing type, a membrane type, and an adsorption type. The processing gas that has passed through the air dryer 55 is sent to the pump 56.

The pump 56 is provided on the circulation line 51 so as to be located on the downstream side of the air dryer 55. The pump 56 is a device for pumping the processing gas. The pump 56 is, for example, a dry vacuum pump, and a more specific example is a diaphragm pump. By operating the pump 56, the processing gas circulates in the circulation line 51. The processing gas that has passed through the pump 56 is sent to the regulating valve 57.

The regulating valve 57 is provided on the circulation line 51 so as to be on the downstream side of the pump 56. The regulating valve 57 is a valve that regulates the flow rate of the processing gas returned to the chamber 10. The regulating valve 57 is, for example, a needle valve. By adjusting the opening / closing amount of the regulating valve 57, the flow rate and pressure of the processing gas on the downstream side of the regulating valve 57 are adjusted. The processing gas that has passed through the regulating valve 57 passes through the first on-off valve 58 and is returned from the inlet 10b to the inside of the chamber 10. The first on-off valve 58 is, for example, a ball valve. In this way, the water contained in the processing gas is removed by the tank 53 and the air dryer 55, so that the purity of hydrogen contained in the processing gas can be improved.

A branch line 51A may be connected to the circulation line 51 on the downstream side of the regulating valve 57 and on the upstream side of the first on-off valve 58. The branch line 51A is an exhaust pipeline that connects the connection point with the circulation line 51 and the outside of the device, and is provided with a second on-off valve 59 (an example of a switching valve). The second on-off valve 59 is, for example, a ball valve. The second on-off valve 59 is closed when the branch line 51A is not used. That is, when the processing gas is circulated in the circulation line 51, the first on-off valve 58 is opened and the second on-off valve 59 is closed. On the other hand, the first on-off valve 58 is closed and the second on-off valve 59 is closed when the atmosphere in the chamber 10 is replaced due to a decrease in the hydrogen purity in the chamber 10 or at the stage before loading and unloading the metal powder. Is opened. As a result, the processing gas in the chamber 10 is exhausted to the outside of the apparatus via the branch line 51A.

As shown in the figure, the pressure in the chamber is adjusted by P ₁ , the pressure in the flow path from the outlet 10a to the pump 56 is adjusted by P ₂ , and the pressure in the flow path from the pump 56 to the regulating valve 57 is adjusted by P ₃ . Assuming that the pressure in the flow path from the valve 57 to the inlet 10b is P ₄ , the relationship is P ₃ > P ₄ > P ₁ > P ₂ .

[Method for producing metal hydride]
FIG. 3 is a flowchart showing a method for producing a metal hydride. The method M1 shown in FIG. 3 is started according to the start operation of the operator.

As shown in FIG. 3, method M1 comprises two steps. First, the step of forming the atmosphere in the chamber 10 (step S10) is performed. First, the operator or the robot places the metal powder S on the sample holder 11 of the chamber 10. Subsequently, the system 100 operates the vacuum pump 16 to reduce the pressure inside the chamber 10 to a predetermined pressure. Then, the system 100 supplies hydrogen gas at a predetermined flow rate from the hydrogen gas cylinder 30 to the chamber 10 via the pipe 42. Then, the exhaust speed is adjusted so that the pressure in the chamber 10 is maintained at a predetermined pressure. As a result, a hydrogen atmosphere is formed in the chamber 10.

Next, a step (step S12) of generating hydrogen brazma and allowing it to act on the metal powder is executed. The system 100 operates a microwave oscillator 20 to inject microwaves having a predetermined power and a predetermined frequency into the chamber 10. At that time, the system 100 is adjusted by the tuner 23 so that the microwave reflected power is minimized. As a result, hydrogen plasma excited by microwaves is generated in the chamber 10, and the metal powder S placed on the sample holder 11 is plasma-treated. During the plasma processing, the system 100 vibrates the sample holder 11 by the vibration generator 14 to cause the metal powder S to flow. After the lapse of a predetermined processing time, the system 100 turns off the power of the microwave oscillator 20, the vibration generator 14, and the infrared heating device 12, and stops the supply of hydrogen gas. After that, the operator or the robot opens the inside of the chamber 10 to the atmosphere and takes out the plasma-treated sample. This completes the series of steps of the method M1 for producing a metal hydride.

[Processing gas adjustment method]
FIG. 4 is a flowchart showing a processing gas adjusting method according to the embodiment. The method M2 shown in FIG. 4 is performed during or during the execution or interruption of step S10 or step S12 of FIG.

As shown in FIG. 4, first, a step (step S20) of delivering the processing gas from the chamber 10 to the circulation line 51 is executed. In step S20, the processing gas is discharged to the circulation line 51 from the delivery port 10a of the chamber 10.

Subsequently, a step (step S22) of passing the check valve 52 through the processing gas is executed. In step S22, the processing gas passes through the check valve 52 and is sent to the tank 53.

Subsequently, the step of passing the liquid through the processing gas (step S24) is executed. In step S24, the processing gas passes through the liquid stored in the tank 53. The processing gas is cooled as it passes through the liquid, and the water vapor in the processing gas returns to water and is trapped in the liquid. Furthermore, the metal powder contained in the processing gas and the by-products during plasma generation are also trapped in the liquid. The processing gas that has passed through the liquid is sent to the air dryer 55.

Subsequently, a step (step S26) of passing the air dryer 55 through the processing gas is executed. In step S26, the air dryer 55 removes water vapor contained in the passing processing gas. The processing gas that has passed through the air dryer 55 is sent to the pump 56.

Subsequently, a step (step S28) of passing the pump 56 through the processing gas is executed. In step S28, the processing gas is pumped by the pump 56. The processing gas that has passed through the pump 56 is sent to the regulating valve 57.

Subsequently, a step (step S30) of passing the regulating valve 57 through the processing gas is executed. In step S30, the flow rate of the processing gas pumped by the pump 56 is adjusted. The processed gas whose flow rate has been adjusted is returned to the chamber 10 in step S32.

This completes the flowchart shown in FIG. By executing the flowchart shown in FIG. 4, it is possible to remove water vapor and the like contained in the processing gas, so that it is possible to suppress a decrease in the purity of hydrogen.

The step of opening the drain valve 54 and recovering the metal powder or the like contained in the liquid may be executed at an appropriate timing. Further, when it is desired to exhaust the processing gas inside the chamber 10 using the branch line 51A, the first on-off valve 58 may be closed and then the second on-off valve 59 may be opened for exhaust. When the processing gas inside the chamber 10 is exhausted, the step of forming the atmosphere inside the chamber 10 (step S10) shown in FIG. 3 is executed. The process of exhausting and the step of forming the atmosphere in the chamber 10 (step S10) may be executed at the same time.

[Summary of embodiments]
According to the processing gas adjusting device 50 according to the present embodiment, the processing gas in the chamber 10 is sent to the circulation line 51, water is removed by the air dryer 55 provided in the circulation line 51, and the gas is returned to the chamber 10 again. Is done. Therefore, according to the processing gas adjusting device 50, it is possible to suppress a decrease in the purity of hydrogen in the processing gas in the chamber 10 when the metal hydride is produced.

According to the processing gas adjusting device 50 according to the present embodiment, the processing gas is cooled as it passes through the liquid in the tank 53, and the water vapor in the processing gas returns to water and is trapped in the liquid. Furthermore, metal powder contained in the processing gas and by-products during plasma generation are also trapped in the liquid. This prevents the metal powder of the raw material and the by-products during plasma generation from reaching the pump 56. Therefore, wear and malfunction of parts of the pump 56, and dust explosion of metal powder are avoided. Therefore, according to the processing gas adjusting device 50, it is possible to further suppress the decrease in the purity of hydrogen in the processing gas in the chamber 10 when producing the metal hydride, and it is safe while avoiding the failure of the pump 56. Can be improved.

Since the processing gas adjusting device 50 according to the present embodiment includes the drain valve 54, the metal powder trapped in the liquid and the by-products during plasma generation can be recovered and reused.

Since the processing gas adjusting device 50 according to the present embodiment includes the check valve 52, it is possible to prevent the liquid in the tank 53 from flowing back into the chamber 10.

Since the processing gas adjusting device 50 according to the present embodiment includes the adjusting valve 57, the flow rates of the processing gas sent to the chamber 10 and the processing gas drawn from the chamber 10 can be adjusted.

Since the processing gas adjusting device 50 according to the present embodiment includes the branch line 51A, the first on-off valve, and the second on-off valve, either circulation of the processing gas or discharge of the processing gas to the outside can be selected. For example, when the purity of hydrogen in the processing gas deviates significantly from the set value, the processing gas adjusting device 50 discharges the processing gas in the chamber from the branch line while supplying new hydrogen gas to the chamber. The processing gas of can be replaced. As a result, work efficiency can be improved.

Although various embodiments have been described above, various modifications can be configured without being limited to the above-described embodiments. For example, the first on-off valve 58 and the second on-off valve 59 may be composed of one switching valve (three-way valve).

10 ... Chamber, 16 ... Vacuum pump (example of exhaust device), 18 ... Microwave generation mechanism (example of plasma generator), 30 ... Hydrogen gas cylinder (example of gas supply device), 42 ... Piping (example of gas supply device) ), 50 ... Processing gas regulator, 51 ... Circulation line, 51A ... Branch line, 52 ... Check valve, 53 ... Tank, 54 ... Drain valve (an example of discharge mechanism), 55 ... Air dryer, 56 ... Pump, 57 ... Control valve, 58 ... 1st on-off valve (example of switching valve), 59 ... 2nd on-off valve (example of switching valve), 100 ... system, S ... metal powder.

Claims (9)

A hydrogen plasma generated in a chamber in an atmosphere using the supplied hydrogen gas as a processing gas is allowed to act on the metal powder in the chamber to be connected to a device for producing a metal hydride, and the purity of hydrogen in the processing gas is increased. It is a processing gas adjusting device that adjusts
A circulation line that returns the processing gas sent from the chamber to the chamber,
A pump provided in the circulation line for pumping the processing gas,
An air dryer provided in the circulation line so as to be located on the upstream side of the pump to remove water contained in the processing gas, and
A processing gas regulator equipped with. The processing gas adjusting device according to claim 1, further comprising a tank provided in the circulation line so as to be located on the upstream side of the air dryer and storing a liquid through which the processing gas passes. The processing gas adjusting device according to claim 2, further comprising a discharging mechanism for discharging the liquid from the tank. The processing gas adjusting device according to claim 2 or 3, which is provided in the circulation line so as to be located on the upstream side of the tank and includes a check valve for preventing the backflow of the processing gas from the tank to the chamber. .. The processing gas according to any one of claims 1 to 4, which is provided in the circulation line so as to be located on the downstream side of the pump and includes a control valve for adjusting the flow rate of the processing gas returned to the chamber. Adjustment device. A branch line connected to the circulation line on the downstream side of the regulating valve and connecting the circulation line to the outside of the device,
A switching valve that switches the flow of the processing gas between the circulation line and the branch line,
The processing gas adjusting device according to claim 5. The switching valve is
A first on-off valve provided in the circulation line so as to be located on the downstream side of the connection point between the circulation line and the branch line.
The second on-off valve provided in the branch line and
The processing gas adjusting device according to claim 6. In a method of producing a metal hydride by allowing a hydrogen plasma generated in a chamber in an atmosphere using the supplied hydrogen gas as a processing gas to act on a metal powder in the chamber, the purity of hydrogen in the processing gas is adjusted. It is a processing gas adjustment method to be performed.
The process of sending the processing gas from the chamber to the circulation line and
A step of passing the treated gas through an air dryer provided in the circulation line to remove water contained in the treated gas, and a step of removing the water contained in the treated gas.
A step of returning the processing gas that has passed through the air dryer to the chamber using a pump, and
Processing gas adjustment method including. A chamber that houses metal powder,
A gas supply device that supplies hydrogen gas to the chamber as a processing gas,
A plasma generator that generates hydrogen plasma in a chamber in a hydrogen atmosphere,
An exhaust device that decompresses the inside of the chamber and
A circulation line that returns the processing gas sent from the chamber to the chamber,
A pump provided in the circulation line for pumping the processing gas,
An air dryer provided in the circulation line so as to be located on the upstream side of the pump to remove water contained in the processing gas, and
A system for producing metal hydrides.

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