JP4072985B2 - Hydrogen production method and apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method and apparatus for producing hydrogen using silicon as a raw material.
[0002]
[Prior art]
Most of the hydrogen consumed in Japan is obtained from petroleum or natural gas by steam reforming or partial oxidation, and is self-consumed in the complex for ammonia synthesis and methanol production. However, because these hydrogens are of low purity, hydrogen produced by electrolysis of water and salt electrolysis, or by-product hydrogen from the petroleum refining process, is used for external sales. The current situation is.
[0003]
However, hydrogen obtained by such a conventional method is generated in a high-temperature and high-pressure environment of several tens to several hundreds of atmospheres and several hundreds of degrees Celsius, requires large energy for production, and is expensive. Therefore, a production method capable of obtaining high purity hydrogen at a low cost is desired.
[0004]
On the other hand, it is a known fact that hydrogen is generated when silicon is heated in an alkaline solution, but there is also a fact that a large amount of silicon that can be a hydrogen source is discarded in the field of semiconductor device manufacturing. . Because it is possible to supply abundant raw materials at low cost such as silicon scrap, and because it can be sufficiently performed in an environment where hydrogen generation reaction between silicon and an alkaline liquid can be easily set at atmospheric pressure, 100 ° C. or less, It can be said that the hydrogen production method using silicon is promising.
[0005]
[Problems to be solved by the invention]
However, the hydrogen production method using silicon as a raw material as described above needs to be suitable for practical use in industrialization in which hydrogen can be supplied efficiently and stably.
[0006]
For example, in a hydrogen generation reaction by mixing silicon and an alkaline aqueous solution, silicate ions are generated in addition to hydrogen gas in the solution, but an excessive high-concentration alkaline solution is simply used to generate a large amount of hydrogen gas. When a large amount of silicon is supplied, silicate ions become gelled, which causes a problem that production of hydrogen gas is inhibited.
[0007]
Also, the reaction between silicon and the aqueous alkaline solution starts vigorously immediately after the contact between the two, and after a few minutes, most of the hydrogen gas that can be generated is generated, and thereafter only a slight reaction continues. That is, since the hydrogen generation rate changes greatly from the start to the end of the reaction, it is difficult to supply quantitative hydrogen simply by taking out the generated hydrogen gas as it is.
[0008]
Furthermore, it is conceivable that silicon as a raw material is supplied as a powder such as silicon scrap as described above. In such a case, it is possible to introduce water vapor in a reaction system that warms an alkaline aqueous solution. There is a possibility of clogging in the piping near the container and mixing of impurity gas into the reaction system.
[0009]
In view of the above problems, an object of the present invention is to avoid the gelation of silicate ions that cause the inhibition of hydrogen gas generation in a hydrogen production method in which hydrogen is generated by mixing silicon and an alkali solution. The object is to provide a method and an apparatus capable of producing hydrogen well. Another object of the present invention is to provide a hydrogen production method and apparatus suitable for practical use capable of continuously supplying hydrogen in a constant amount.
[0010]
[Means for Solving the Problems]
In order to achieve the above-mentioned object, the hydrogen production method according to the first aspect of the present invention provides hydrogen by supplying powder silicon and an alkaline liquid to a reaction vessel and causing contact reaction under heating in the reaction vessel. In the hydrogen production method to be generated, powder silicon is previously mixed with water to form a slurry, and this silicon slurry is supplied to a reaction vessel ,
The supply of the silicon slurry and / or the alkali liquid is controlled so that the internal pressure of the reaction container is maintained within a predetermined pressure range in accordance with the flow rate of hydrogen from the reaction container .
[0012]
A hydrogen production apparatus according to a second aspect of the present invention includes a pressure-resistant structure reaction vessel, a constant temperature heating device for heating the reaction vessel to maintain the reaction temperature, and mixing powder silicon with water. A first tank for storing the slurry in a slurry state; a second tank for storing an alkaline liquid; a liquid supply device for feeding the silicon slurry in the first tank and the alkaline liquid in the second tank into a reaction vessel; and the reaction A gas deriving device for deriving hydrogen generated in the container to the outside,
The gas deriving device comprises pressure measuring means for measuring the gas pressure in the reaction vessel and gas flow rate controlling means for controlling the hydrogen deriving flow rate;
The liquid supply device has a reaction vessel internal pressure determined in advance according to the flow rate of hydrogen from the reaction vessel based on the pressure value measured by the pressure measurement unit and the flow rate value controlled by the gas flow rate control unit. Liquid supply control means for controlling the supply of the silicon slurry and / or the alkali liquid so as to be kept within the above pressure range.
[0014]
Furthermore, the hydrogen production apparatus according to the invention described in claim 3 is the hydrogen production apparatus according to claim 2 , wherein the gas flow rate control means derives hydrogen at a predetermined flow rate and a mass flow controller. It is equipped with.
[0015]
The hydrogen production apparatus according to claim 4 is the hydrogen production apparatus according to claim 2 , wherein the liquid supply control means includes a pump, and a discharge flow path of the pump is connected to the reaction vessel. In addition, the suction flow path is connected in parallel to the first tank and the second tank via open / close valves that can be selectively opened and closed, and the pump is started and stopped based on the pressure value measured by the pressure measuring means, and Each on-off valve is opened and closed.
[0016]
The hydrogen production method according to the first aspect of the present invention is a hydrogen production method in which hydrogen is generated by mixing powder silicon and an alkaline liquid, and raw material powder silicon is mixed with water in advance and supplied in a slurry state. As a result, the amount of liquid in the reaction vessel increases due to the presence of mixed water compared to the case where silicon is supplied in powder form, and the silicate ion concentration in the solution is suppressed, causing the hydrogen gas generation to be inhibited. The generation of gel-like by-products is also suppressed. In addition, if silicon is supplied in a slurry state, the vigorous reaction immediately after the contact between silicon and the alkali liquid can be suppressed, so that the alkali liquid can be used at a higher concentration, and the silicon can be used efficiently, that is, the amount of hydrogen gas generated can be increased. Can also be planned.
[0017]
Also, as the hydrogen generation reaction proceeds, the pressure inside the reaction vessel increases due to the generated hydrogen gas, so even if you continue to supply the raw material into the reaction vessel and continue the hydrogen generation reaction, it will eventually remain in the reaction vessel. The hydrogen gas is filled up to the upper limit of pressure, and the hydrogen generation reaction cannot be continued without deriving the hydrogen gas and lowering the internal pressure of the container. Therefore, if the raw material is additionally supplied as appropriate while deriving the hydrogen gas filled in the reaction vessel, the hydrogen generation reaction can be easily continued.
[0018]
At this time, by controlling the additional supply of silicon slurry and an alkaline solution as a reaction vessel internal pressure depending on the derived flow rate of hydrogen gas is maintained within a pressure range set in advance, efficiently continue the hydrogen generation reaction Hydrogen can be obtained continuously and quantitatively.
[0019]
According to a second aspect of the present invention, there is provided a hydrogen production apparatus in which powder silicon is mixed with water in a first tank and stored in a slurry state, an alkali liquid is stored in a second tank, and the liquid supply device stores the first tank. The silicon slurry and the alkaline liquid in the second tank were sent into a pressure-resistant reaction vessel, and the reaction vessel was heated with a constant temperature heating device to perform a hydrogen generation reaction while maintaining the reaction temperature, and was generated in the reaction vessel. Hydrogen is led out of the reaction vessel by a gas lead-out device and recovered.
[0020]
According to the apparatus having the above-described configuration, the supply of the raw material silicon into the reaction vessel by the liquid supply apparatus is performed in a slurry state from the first tank. The supply of silicon together with the alkali solution from the two tanks can be controlled smoothly and easily, and the generation of gel by-products accompanying the progress of the reaction can be suppressed, so that the generation of hydrogen gas proceeds well. Therefore, according to this apparatus, the continuous supply of the mechanical raw material and the continuous reaction can be performed, and efficient and continuous hydrogen production can be realized.
[0021]
Further , the gas deriving device includes a pressure measuring unit for measuring the gas pressure in the reaction vessel and a gas flow rate controlling unit for controlling the hydrogen deriving flow rate, and the pressure measured by the liquid measuring unit of the liquid supplying device with the pressure measuring unit. Silicon slurry and / or alkali liquid so that the internal pressure of the reaction vessel is maintained within a predetermined pressure range according to the flow rate of hydrogen from the reaction vessel based on the value and the flow rate value controlled by the gas flow rate control means If the additional supply is controlled, the hydrogen generation reaction can be automatically continued, and hydrogen can be produced quantitatively continuously.
[0022]
As the gas flow rate control means for controlling the flow rate of hydrogen out of the reaction vessel, a device equipped with a condenser and a mass flow controller is simple. With this configuration, hydrogen can be led out from the reaction vessel at a predetermined flow rate.
[0023]
Further, as a specific configuration of the liquid supply apparatus in the hydrogen production apparatus of the present invention, since the raw material silicon is in a slurry state, using a pump is simple and easy in terms of control of the raw material supply. For example, when silicon slurry and alkali liquid are sent from the first tank and the second tank to the reaction vessel via the pump, the discharge channel of the pump is connected to the reaction vessel, and the suction channel can be selectively opened and closed. The liquid supply control is configured such that the first tank and the second tank are connected in parallel through a simple on-off valve and the pump is started and stopped and the on-off valve is opened and closed based on the pressure value measured by the pressure measuring means. As a means, it is possible to easily control the additional supply of raw materials to continue the hydrogen generation reaction so that quantitative hydrogen derivation and recovery can be continuously performed.
[0024]
DETAILED DESCRIPTION OF THE INVENTION
A hydrogen production apparatus as an embodiment of the present invention is shown in a schematic configuration diagram of FIG. This apparatus warms the reaction vessel 1 based on the measurement result of the temperature sensor 8 consisting of a reaction vessel 1 having a pressure capacity of 12 L actual volume and a thermocouple for confirming the solution temperature in the reaction vessel 1. A constant temperature water circulation device 2 as a constant heating device to be maintained, and as a liquid supply device, a first tank 3 in which powder silicon and water are mixed and stored in a slurry state, and a second tank in which alkaline liquid is stored 4 and the first tank 3 and the second tank 4 are connected in parallel to each other through openable / closable valves (11, 12), and the discharge flow path is connected to the reaction vessel 1. The pump 5 is provided.
[0025]
Furthermore, a condenser 6 and a mass flow controller 7 for deriving hydrogen gas at a predetermined flow rate are provided as a gas deriving device for deriving hydrogen gas generated in the reaction vessel to the outside.
[0026]
In addition, in this apparatus, the pressure sensor (pressure measurement means) 9 which measures the gas pressure in the reaction container 1 is provided, Based on the pressure value measured by this pressure sensor 9, and the flow rate value of the said hydrogen gas. And a control device (not shown) for controlling the start and stop of the pump 5 on the liquid supply device side and the opening and closing of the on-off valves (11, 12).
[0027]
With this control device, the silicon slurry from the first tank 3 and the second tank 4 and the reaction vessel internal pressure are maintained within a predetermined pressure range in accordance with the derivation of hydrogen from the reaction vessel 1 while the device is being driven. The supply and addition of the alkaline liquid is controlled, and the hydrogen generation reaction is continued so that quantitative hydrogen derivation and recovery can be continuously performed.
[0028]
When the additional supply of the raw material is repeated to some extent and the drain valve 13 is opened when the solution in the reaction vessel 1 reaches a predetermined amount, the solution is discharged from the reaction vessel 1 to the drain tank 10, and the drain valve After closing 13, the raw material supply can be started again to continue the hydrogen generation reaction.
[0029]
【Example】
As a first reference example of the present invention, a case where a hydrogen production reaction is performed using the hydrogen production apparatus shown in FIG. 1 and continuous hydrogen production is performed by continuing the reaction by additional supply of raw materials will be described below. . As an initial state, first, 1 L of 0.5 N sodium hydroxide aqueous solution is accommodated in the reaction vessel 1 and heated by the constant temperature heating device 2 to maintain the liquid temperature at 80 ° C. While stirring and mixing with water, it is stored in a 10 wt% silicon slurry state, and a 1 N sodium hydroxide aqueous solution is stored in the second tank 4.
[0030]
At the same time as the pump 5 is started by the control device, the respective open / close valves (11, 12) are opened sequentially to give 0.1 L of 10 wt% silicon slurry from the first tank 3 and 0.1 L of 1 N sodium hydroxide aqueous solution from the second tank 4. Are introduced into the reaction vessel 1 to start a hydrogen production reaction. The addition of the 1N sodium hydroxide aqueous solution is for resisting the dilution of the alkaline aqueous solution with the moisture of the slurry.
[0031]
After the start of the reaction, measurement of the amount of hydrogen gas generated and the additional supply of 0.1 L of 10 wt% silicon slurry and 0.1 L of 1N sodium hydroxide aqueous solution were repeated every 10 minutes to continue the hydrogen generation reaction. In this reference example , after the raw material supply at this station, nine additional raw material supply operations were repeated. On the way, when the amount of the solution in the reaction vessel 1 reaches a certain amount, the drain valve 13 is opened, the solution is discharged to the drain tank 10 and reduced to 1 L, and then the additional raw material supply is resumed.
[0032]
The hydrogen gas generation amount (L) measured every 10 minutes is shown by a bar graph, and the consumption rate (%) relative to the input silicon is shown by a line graph in FIG. As a result, first, by adding silicon in a slurry state, the same amount of hydrogen generation reaction can be continued each time the raw material is supplied without generating a gel-like by-product that inhibits hydrogen gas generation. It was confirmed that continuous hydrogen production was possible. In addition, the silicon consumption rate in the reaction at each interval was about 80%, and the hydrogen generation reaction was performed with very high efficiency.
[0033]
Next, as a second reference example, when the continuous reaction performed in the first reference example is continued for a long time, the raw materials (10 wt% silicon slurry 0.1 L and 1 N sodium hydroxide aqueous solution 0.1 L) are used. ) Was examined to see if there was a change in the hydrogen generation process from the additional supply. That is, the integrated value of the amount of hydrogen generated in 10 minutes from the time of additional supply of raw materials immediately after the start of the reaction and at the time when the continuous reaction is continued for a long time from the start of the reaction, here 8 hours, is obtained in each case over time. It was.
[0034]
The results are shown in the line graph of FIG. 3 (horizontal axis: elapsed time (minutes) since supply of raw material, vertical axis: integrated value of generated hydrogen amount (converted to L. 0 ° C.)). As can be seen from FIG. 3, most of the hydrogen produced in the second and third minutes after the start of the feed is immediately after the start of the reaction. As for hydrogen production from the hydrogen, generation of hydrogen was observed only after 6 or 7 minutes had passed from the supply, and the rate of progress of the production reaction was slow.
[0035]
Accordingly, the hydrogen generation from the additional supply of the raw material is not uniform depending on the continuation state of the reaction, and the progress of the hydrogen generation reaction is slowed with a change in the amount of the reaction solution, components, etc. over a long period of time. It was confirmed that there was a tendency.
[0036]
Therefore, in the continuation of the hydrogen generation reaction over a long period of time, the timing of additional supply of raw materials for continuously performing quantitative derivation of hydrogen from the reaction vessel changes as the reaction continues and the hydrogen generation status changes. We examined how to control in response to the above.
[0037]
Theoretically, when the reaction vessel is filled with the hydrogen gas generated in the initial reaction, quantitative derivation of hydrogen to the outside of the vessel is started, and additional supply of raw materials is performed while the hydrogen gas in the reaction vessel is decreasing. If a state in which the reaction vessel is filled with hydrogen before all the hydrogen has been derived is obtained, quantitative hydrogen derivation over a long period of time can be performed without interruption of hydrogen derivation.
[0038]
Therefore, if the additional supply of the raw material is controlled based on the change in the internal pressure accompanying the decrease in the hydrogen gas in the reaction vessel, it is possible to continuously maintain the quantitative derivation of hydrogen. That is, the supply of the raw material may be controlled so that hydrogen gas is generated in accordance with the hydrogen discharge flow rate so that the inside of the reaction vessel is maintained within a predetermined pressure range.
[0039]
Therefore, first, based on the upper limit value and the lower limit value determined in advance as the pressure range, what is the internal pressure of the reaction vessel that decreases with hydrogen derivation for the maximum and minimum hydrogen derivation rates for the reaction vessel 1 in FIG. It was determined by simulation under certain conditions whether or not the raw material should be additionally supplied at that time.
[0040]
As simulation conditions, the upper limit value of the range pressure is set to 0.245 MPa from the pressure resistance of the apparatus, and the lower limit value is set to 0.049 MPa, which is a lower limit pressure that can be stably controlled by the mass flow controller 7. First, the reaction vessel is filled with hydrogen gas. The change in the pressure in the reaction vessel was measured when hydrogen was led out at a maximum hydrogen lead speed of 1 L / min and a minimum hydrogen lead speed of 0.1 L / min. The results are shown in the graphs of FIGS. 4A and 4B, respectively, and the pressure in the reaction vessel decreases almost linearly as hydrogen is derived.
[0041]
In response to such changes in the reaction vessel internal pressure at the maximum and minimum derivation speeds, the hydrogen in the reaction vessel so that the internal pressure of the reaction vessel satisfies the upper and lower limits of the pressure range in the entire reaction continuation process for a long time (about 8 hours in this case). In order to perform the generation, it is only necessary to maintain the upper and lower limits in the pressure range when the hydrogen generation state shown in FIG.
[0042]
When such a state is simulated, the results shown in the graphs of FIGS. 5A and 5B are obtained at the maximum and minimum derivation speeds, respectively. From this result, additional raw materials are supplied when the internal pressure of the reaction vessel reaches 0.108 MPa at the maximum hydrogen lead-out speed of 1 L / min, and when the internal pressure of the reaction vessel reaches 0.059 MPa at the minimum hydrogen lead-out speed of 0.1 L / min. By doing so, the deriving of hydrogen from the reaction vessel is not interrupted, and a certain amount of deriving of hydrogen can be maintained over a prolonged reaction state.
[0043]
From the above results, if the pressure value in the reaction vessel to be supplied in accordance with the hydrogen derivation speed is obtained in advance, it is suitable only by measuring the pressure value in the reaction vessel in the long-term continuation of the hydrogen generation reaction. It can be controlled to perform additional supply of raw materials at the timing, and continuous quantitative derivation of hydrogen can be easily maintained.
[0044]
Next, as an example of the present invention , hydrogen was quantitatively manufactured by continuing the reaction by the raw material additional supply control using the apparatus of FIG. 1 under the condition setting based on the simulation result. In this example, the hydrogen derivation speed was 1 L / min, and the pressure in the reaction vessel, which is the timing for performing additional raw material supply, was 0.108 MPa.
[0045]
The basic operation of the apparatus is the same procedure as in the first reference example . First, as an initial state, 1 L of 0.5 N sodium hydroxide aqueous solution is accommodated in the reaction vessel 1, heated by the constant temperature heating device 2 to maintain the liquid temperature at 80 ° C., and the reaction vessel 1 is purged with nitrogen gas. .
[0046]
At the same time as the pump 5 is started by the control device, the respective open / close valves (11, 12) are opened sequentially to give 0.1 L of 10 wt% silicon slurry from the first tank 3 and 0.1 L of 1 N sodium hydroxide aqueous solution from the second tank 4. Are introduced into the reaction vessel 1, and when a predetermined amount of raw material is introduced, the on-off valves (11, 12) are closed and the pump 5 is stopped. At the same time as the introduction of these raw materials into the reaction vessel 1, the hydrogen generation reaction starts. At the same time, measurement of the pressure in the reaction vessel 1 by the pressure sensor 9 is also started.
[0047]
When the measured pressure value reaches 0.196 MPa, which is the upper limit based on the apparatus pressure resistance value, hydrogen gas is led out of the reaction vessel at a rate of 1 L / min and collected by the mass flow controller 7. When the measured value by the pressure sensor 9 reaches 0.108 MPa, the pump 5 and the on-off valves (11, 12) are driven and controlled, and the raw material (10 wt% silicon slurry 0.1 L is supplied from the first tank 3 and the second tank 4 respectively. And 1N aqueous sodium hydroxide solution (0.1 L). The additional supply of the raw material based on the measurement value by the pressure sensor 9 is repeated.
[0048]
When the amount of the solution in the reaction vessel 1 reaches a predetermined amount, the derivation of hydrogen is stopped, the drain valve 13 is opened, the solution is discharged to the drain tank 10, and the amount of liquid in the reaction vessel is reduced to 1L. Thereafter, the raw material is supplied again, and when the internal pressure of the container reaches 0.196 MPa, hydrogen is led out at the predetermined speed, and the additional supply of the raw material based on the measured value by the pressure sensor 9 is repeated.
[0049]
The raw material additional supply timing, the change in the pressure in the vessel (MPa), and the hydrogen gas lead-out amount (L / min) in the hydrogen production process described above are shown in FIG. As described above, quantitative quantitative production of hydrogen could be performed only by controlling the additional supply of raw materials based on the pressure value in the reaction vessel.
[0050]
In addition, although the silicon slurry used as the raw material in the present invention is a mixture of powdered silicon and water, the silicon supply source is not limited. For example, silicon scrap generated from a semiconductor production line is used. Also good. In this case, since the waste is used, the production cost of hydrogen is greatly reduced. In addition, alkaline waste liquid can be used as the alkaline liquid.
[0051]
【The invention's effect】
As described above, according to the hydrogen production method of the present invention, since raw material silicon is supplied in a slurry state mixed with water, it is possible to suppress the generation of gel-like by-products that inhibit hydrogen gas generation, Since vigorous reaction immediately after the contact between silicon and the alkaline solution is also suppressed, the alkaline solution can be used at a higher concentration, which not only enables high-efficiency utilization of silicon but also facilitates the supply of silicon raw materials. Hydrogen gas can be continuously generated by continuing the hydrogen generation reaction by supplying additional raw materials.
[0052]
Moreover, according to the hydrogen production apparatus of the present invention, it is possible to easily control the supply of raw materials and the recovery of produced hydrogen, and there is an effect that the mechanical production of hydrogen can be performed easily. Furthermore, the additional supply of the raw material can be easily controlled based on the pressure value in the reaction vessel, and the quantitative reaction of hydrogen can be continuously performed while maintaining the reaction.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram of a hydrogen production apparatus as an embodiment of the present invention.
FIG. 2 is a bar graph showing changes over time in hydrogen production and silicon consumption rate in the hydrogen production process using the apparatus of FIG. 1 as a first reference example of the present invention (horizontal axis: elapsed time (minutes), vertical axis : Hydrogen gas generation amount (L) every 10 minutes) and a line diagram (horizontal axis: elapsed time (minutes), vertical axis: consumption rate (%) relative to input silicon).
FIG. 3 is a line diagram showing the integrated value of the amount of hydrogen generated in 10 minutes from the time of raw material supply as a second reference example of the present invention (horizontal axis: elapsed time (minutes), vertical axis: integrated hydrogen at 0 ° C. Value (L)), which shows the case of raw material supply immediately after the start of reaction (♦: black diamond) and the case of raw material supply 8 hours after the start of reaction (■; black square).
4 is a diagram (horizontal axis: time (minutes), vertical axis: pressure in the container (MPa)) showing the time change of the pressure in the reaction container with the derivation of hydrogen from the reaction container in the hydrogen production apparatus of FIG. Yes, (a) shows the case where the maximum hydrogen derivation speed is 1 L / min, and (b) shows the case where the minimum hydrogen derivation speed is 0.1 L / min.
FIG. 5 is a reaction based on the results shown in FIGS. 4 and 3 when raw materials are additionally supplied immediately after the start of the reaction (♦: black rhombus) and 8 hours after the start of the reaction (■; black square). It is a diagram (horizontal axis: time (minutes), vertical axis: pressure in the container (MPa)) showing the simulation result of the time change of the pressure in the container, and (a) is the maximum hydrogen derivation speed of 1 L / min. b) shows the case where the minimum hydrogen derivation speed is 0.1 L / min.
6 shows an example of the present invention, in which the internal pressure of the container when hydrogen is continuously quantitatively manufactured by controlling the additional supply of the raw material based on the pressure value in the reaction container using the hydrogen production apparatus of FIG. Is a polygonal graph (horizontal axis: hydrogen derivation time (minutes), vertical axis: pressure in the vessel (MPa) and hydrogen gas derivation amount (L)) showing the change of the gas and the hydrogen gas derivation amount along with the raw material supply timing. .
[Explanation of symbols]
1: Reaction vessel 2: Constant temperature heating device 3: First tank 4: Second tank 5: Pump 6: Condenser 7: Mass flow controller 8: Temperature sensor 9: Pressure sensor 10: Drain tank 11, 12: Open / close valve 13: Drain valve

Claims (4)

In a hydrogen production method for generating hydrogen by supplying powder silicon and an alkaline liquid to a reaction vessel and causing contact reaction under heating in the reaction vessel,
Powder silicon is previously mixed with water to form a slurry, and this silicon slurry is supplied to the reaction vessel ,
A method for producing hydrogen, characterized in that the supply of silicon slurry and / or alkali liquid is controlled so that the internal pressure of the reaction vessel is maintained within a predetermined pressure range in accordance with the flow rate of hydrogen from the reaction vessel . A pressure-resistant reaction vessel,
A constant temperature heating device for heating the reaction vessel to maintain the reaction temperature;
A first tank that mixes powdered silicon with water and stores it in a slurry state;
A second tank for storing alkaline liquid;
A liquid supply device for feeding the silicon slurry in the first tank and the alkaline liquid in the second tank into a reaction vessel;
A gas deriving device for deriving hydrogen generated in the reaction vessel to the outside ,
The gas deriving device comprises pressure measuring means for measuring the gas pressure in the reaction vessel and gas flow rate controlling means for controlling the hydrogen deriving flow rate;
The liquid supply device has a reaction vessel internal pressure determined in advance according to the flow rate of hydrogen from the reaction vessel based on the pressure value measured by the pressure measurement unit and the flow rate value controlled by the gas flow rate control unit. A hydrogen production apparatus comprising liquid supply control means for controlling the supply of silicon slurry and / or alkali liquid so as to be maintained within a predetermined pressure range . The hydrogen production apparatus according to claim 2 , wherein the gas flow rate control unit includes a condenser and a mass flow controller for deriving hydrogen at a predetermined flow rate. The liquid supply control means includes a pump, and a discharge flow path of the pump is connected to the reaction vessel, and an intake flow path can be selectively opened and closed in parallel with the first tank and the second tank. 3. The hydrogen production apparatus according to claim 2 , wherein the apparatus is connected and configured to start and stop the pump and open and close each on-off valve based on a pressure value measured by the pressure measuring means.

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