JP2011006769A - Water electrolysis apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To stably generate a hydrogen gas in a water electrolysis apparatus.SOLUTION: The water electrolysis apparatus is provided with a water electrolysis cell 11 of which the inside is partitioned into an anode side 23 and a cathode side 24 by a solid polymer electrolyte film 22, a power generator 12 supplying power to the solid polymer electrolyte film 22, a second circulating water path 17 for circulating and feeding water to the cathode side of the solid polymer electrolyte film 22, a second gas-liquid separation tank 18 separating the hydrogen gas from water flowing in the second circulating water path 17, a hydrogen taking out path 19 having a hydrogen control valve 33 taking out the separated hydrogen gas, a pressure adjusting means adjusting pressure in the second circulating water path 17 and a control device 20 controlling the hydrogen control valve 33 and the pressure adjusting means according to the power amount supplied to the solid polymer electrolyte film 22 from the power generator 12.

Description

  The present invention relates to a water electrolysis apparatus capable of producing oxygen and hydrogen by electrolyzing water using a solid polymer electrolyte membrane as a diaphragm.

  By using fossil fuels such as oil and coal, carbon dioxide is released into the atmosphere, leading to global warming. As a clean system that replaces fossil fuels, the use of hydrogen in fuel cells, hydrogen engines, and the like has attracted attention. A water electrolysis apparatus that produces hydrogen gas or oxygen gas by electrolysis of water (hereinafter, water electrolysis) can produce hydrogen gas and oxygen gas relatively easily and without pollution. On the other hand, examples of a power generation device using natural energy that does not adversely affect the global environment include wind power generation and solar power generation. And the technique which applied the electric power generating apparatus using this natural energy as a power supply of a water electrolysis apparatus has already been proposed.

  For example, in the water electrolysis system utilizing natural energy described in Patent Document 1 below, a water electrolysis device that electrolyzes water to generate hydrogen and oxygen, and a current / voltage that controls the current / voltage for driving the water electrolysis device A voltage control device and a natural energy power generation device such as a wind power generation device that obtains electricity by natural energy are provided, and hydrogen is generated by a water electrolysis device using electric power generated by the wind power generation device or the like.

Japanese Patent Laying-Open No. 2005-330515

  The hydrogen generation efficiency of the water electrolysis apparatus is closely related to the supplied power, and when the supplied power is reduced, the amount of hydrogen generated is reduced and the hydrogen generation efficiency is reduced. When the generated hydrogen gas is supplied to a fuel cell, a hydrogen engine, or the like and used, if the amount of supplied hydrogen gas fluctuates, it becomes difficult to stably operate the fuel cell, the hydrogen engine, or the like.

  In the conventional water electrolysis apparatus described above, a secondary battery is provided in addition to the natural energy power generation apparatus, and the electric power stored in the secondary battery is replenished even if the power generation amount (current value) due to natural energy fluctuates due to weather conditions. Thus, the supplied power (current value) is maintained almost constant. However, in order for the control device to constantly control the power of the natural energy power generation device and the power of the secondary battery to adjust the power (current value) supplied to the water electrolysis device, excessive equipment is required and the cost is reduced. Is high and energy efficiency is not good.

  The present invention solves the above-described problems, and an object of the present invention is to provide a water electrolysis apparatus capable of generating stable hydrogen gas.

  In order to achieve the above object, a water electrolysis apparatus according to the present invention includes a water electrolysis cell whose interior is divided into an anode side and a cathode side by a solid polymer electrolyte membrane, and power to the solid polymer electrolyte membrane. A power supply device for supplying water, a first circulating water path for circulating water to the solid polymer electrolyte membrane side on the anode side, and a second circulating water for circulating water to the solid polymer electrolyte membrane side on the cathode side A hydrogen separation means for separating hydrogen gas from water flowing through the second circulation water path, a hydrogen extraction means for taking out the hydrogen gas separated by the hydrogen separation means from the second circulation water path, Pressure regulating means for adjusting the pressure in the circulating water path, and control means for controlling the hydrogen extraction means and the pressure regulating means in accordance with the amount of power supplied from the power supply device to the solid polymer electrolyte membrane; Also characterized by comprising It is.

  In the water electrolysis apparatus of the present invention, the pressure regulating means has a second water supply path for supplying water into the second circulating water path.

  In the water electrolysis apparatus of the present invention, the pressure adjusting means has a water discharge path for discharging water from the second circulating water path.

  In the water electrolysis apparatus of the present invention, the hydrogen extraction means includes a hydrogen extraction path connected to the hydrogen separation means, and a hydrogen control valve provided in the hydrogen extraction path, and the control means includes the power supply The opening degree of the hydrogen control valve is adjusted according to the amount of power supplied from the apparatus to the solid polymer electrolyte membrane.

  In the water electrolysis apparatus of the present invention, the control means operates the hydrogen extraction means after setting the hydrogen dissolved amount in the water in the cathode-side water circulation path to the saturated hydrogen amount.

  In the water electrolysis apparatus of the present invention, the power supply device includes a natural energy supply device that supplies electric power obtained by natural energy.

  According to the water electrolysis apparatus of the present invention, the water electrolysis cell whose interior is partitioned into the anode side and the cathode side by the solid polymer electrolyte membrane, and the second water is circulated and supplied to the cathode side solid polymer electrolyte membrane side. A circulating water path, a hydrogen separating means for separating hydrogen gas from water flowing in the second circulating water path, a hydrogen extracting means for taking out the hydrogen gas separated by the hydrogen separating means from the second circulating water path, and a second circulation Pressure adjusting means for adjusting the pressure in the water path and control means for controlling the hydrogen extraction means and the pressure adjusting means in accordance with the amount of power supplied from the power supply device to the solid polymer electrolyte membrane are provided. Therefore, when the amount of electric power supplied to the solid polymer electrolyte membrane fluctuates, the amount of generated hydrogen gas increases or decreases. At this time, hydrogen that can be dissolved in water by increasing or decreasing the pressure in the second circulating water path. The amount of hydrogen gas to be vaporized is increased or decreased, the amount of hydrogen gas to be vaporized is increased or decreased, the amount of hydrogen gas extracted by the hydrogen extraction means can be made constant, stable hydrogen gas supply can be enabled, and the hydrogen generation efficiency can be improved. Can be improved.

  According to the water electrolysis apparatus of the present invention, since the pressure adjusting means is the second water supply path for supplying water into the second circulating water path, the inside of the second circulating water path is pressurized by the second water supply path. As a result, the amount of hydrogen gas is increased or decreased, the amount of hydrogen gas taken out by the hydrogen extraction means can be made constant, and stable hydrogen gas generation can be achieved.

  According to the water electrolysis apparatus of the present invention, since the pressure adjusting means is a water discharge path for discharging water from the second circulation water path, the pressure in the second circulation water path is reduced by the water discharge path. The amount of gas is increased or decreased, the amount of hydrogen gas taken out by the hydrogen removal means can be made constant, and stable generation of hydrogen gas can be made possible.

  According to the water electrolysis apparatus of the present invention, the hydrogen extraction means comprises a hydrogen extraction path connected to the hydrogen separation means and a hydrogen control valve provided in the hydrogen extraction path, and the control means is connected to the power supply apparatus. Since the opening degree of the hydrogen control valve is adjusted according to the amount of power supplied to the solid polymer electrolyte membrane, if the amount of power supplied to the solid polymer electrolyte membrane fluctuates, the opening degree of the hydrogen control valve is changed to the open side or By adjusting to the closing side, the hydrogen pressure taken out by the hydrogen take-out means can be made constant, and stable hydrogen gas supply can be made possible.

  According to the water electrolysis apparatus of the present invention, the control means operates the hydrogen extraction means after setting the hydrogen dissolved amount in the water in the cathode-side water circulation path to the saturated hydrogen amount. By maintaining the amount of hydrogen dissolved in water at the saturated hydrogen amount, the amount of hydrogen dissolved in water, that is, the amount of generated hydrogen gas, is adjusted early when the amount of power supplied to the solid polymer electrolyte membrane fluctuates. be able to.

  According to the water electrolysis apparatus of the present invention, since the power supply apparatus is a natural energy supply apparatus that supplies power obtained by natural energy, hydrogen gas can be generated without adversely affecting the global environment. Can do.

FIG. 1 is a schematic configuration diagram illustrating a water electrolysis apparatus according to an embodiment of the present invention. FIG. 2 is a time chart showing a state change at the start-up in the water electrolysis apparatus of the present embodiment. FIG. 3 is a time chart showing an operation state change in the water electrolysis apparatus of the present embodiment.

  Exemplary embodiments of a water electrolysis apparatus according to the present invention will be described below in detail with reference to the accompanying drawings. In addition, this invention is not limited by this Example.

  FIG. 1 is a schematic configuration diagram showing a water electrolysis apparatus according to an embodiment of the present invention, FIG. 2 is a time chart showing a state change at start-up in the water electrolysis apparatus of this embodiment, and FIG. 3 is this embodiment. It is a time chart showing the driving | running state change in the water electrolysis apparatus.

  As shown in FIG. 1, the water electrolysis apparatus of the present embodiment includes a water electrolysis cell 11, a power generation device (power supply device) 12, a charging device 13, a first circulating water path 14, and a first gas-liquid separation. The tank 15, the oxygen gas extraction path 16, the second circulating water path 17, the second gas-liquid separation tank 18, the hydrogen gas extraction path 19, and the control device 20 are configured. In the water electrolysis apparatus of the present embodiment, a first water supply path 41 and a first water supply valve 42 are provided as first pressurizing means (pressure adjusting means) for pressurizing water in the first circulating water path 14. It has been. Furthermore, a second water supply path 43 and a first water supply valve 44 are provided as second pressurizing means (pressure adjusting means) for pressurizing the water in the second circulating water path 17.

  In the water electrolysis cell 11, an anode is disposed on one side of the solid polymer electrolyte membrane 22 and a cathode is disposed on the other side in the water electrolysis stack 21. It is configured in the electrolytic stack 21. The water electrolysis cell 11 generates oxygen gas on the anode side 23 and hydrogen gas on the cathode side 24 by electrolyzing water with a solid polymer electrolyte membrane.

  The power generation device 12 supplies electric power (current) to the solid polymer electrolyte membrane 22 in the water electrolysis cell 11, and in this embodiment, as a power supply device using natural energy, a wind power generation device, solar A photovoltaic power generation device, a hydroelectric power generation device, a wave power generation device, a geothermal power generation device, an ocean temperature difference power generation device, or the like is applied. In this case, a charging device 13 that stores electric power generated during the day is provided corresponding to the power supply device that cannot generate power at night. Moreover, as the electric power generating apparatus 12, it is also possible to supply the electric power from a system | strain. The control device 20 receives the power obtained by the power generation device 12 and controls the current value and the voltage value of the power supplied to the solid polymer electrolyte membrane 22 of the water electrolysis cell 11, thereby requesting the water electrolysis cell. Water electrolysis can be performed by supplying electric power in an optimal state, and oxygen gas and hydrogen gas can be generated.

  The first circulating water path 14 circulates water to the water electrolysis stack 21 and supplies water to the anode side 23 of the water electrolysis cell 11 to enable water electrolysis. The first circulating water path 14 is connected to the first gas-liquid separation tank 15, and the first circulating water path 14 includes an inlet path 14 a for the water electrolysis stack 21 and an outlet path 14 b from the water electrolysis stack 21. It is composed of A first circulating pump 31 is provided in the inlet path 14 a of the first circulating water path 14. In this case, the first circulating water path 14 and the first gas-liquid separation tank 15 constitute the first circulating water path of the present invention.

  The first gas-liquid separation tank 15 separates and extracts oxygen gas existing in bubbles or dissolved in the circulating water, and an oxygen extraction path 16 for discharging the separated oxygen gas is connected to the upper part of the first gas-liquid separation tank 15. Yes. Further, the first gas-liquid separation tank 15 includes a filter 15a. After the filter 15a removes impurities (for example, eluted metal) generated by electrolysis of water, Supply to the electrolytic stack 21.

  The second circulation water path 17 circulates water to the water electrolysis stack 21 and supplies water to the cathode side 24 of the water electrolysis cell 11 to cool the solid polymer electrolyte membrane and lead out hydrogen gas. It is possible. The second circulating water path 17 is connected to the second gas-liquid separation tank 18, and the second circulating water path 17 includes an inlet path 17 a for the water electrolysis stack 21 and an outlet path 17 b from the water electrolysis stack 21. It is composed of A second circulation pump 32 is provided in the inlet path 17 a of the second circulating water path 17. In this case, the second circulating water path 17 of the present invention is configured by the second circulating water path 17 and the second gas-liquid separation tank 18.

  The second gas-liquid separation tank 18 separates and extracts hydrogen gas present in bubbles or dissolved in the circulating water, and a hydrogen extraction path 19 for discharging the separated hydrogen gas is connected to the upper part of the second gas-liquid separation tank 18. Yes. A hydrogen control valve 33 is provided in the hydrogen extraction path 19. The second gas-liquid separation tank 18 includes a filter 18a. After the filter 18a removes impurities (for example, eluted metal) generated by electrolysis of water, Supply to the electrolytic stack 21.

  A buffer tank 35 is connected to the inlet path 17a in the second circulating water path 17 via an auxiliary path (water discharge path) 34, and a water discharge valve 36 is provided in the auxiliary path 34. Yes. The buffer tank 35 is used to temporarily hold the circulating water according to the amount of hydrogen gas in the second gas-liquid separation tank 18 in the second circulating water path 17.

  The first water supply path 41 supplies water from the outside into the first gas-liquid separation tank 15, so that the first circulating water path 14 and the first gas that are circulating water paths on the anode side 23 of the water electrolysis stack 21 are provided. The pressure of the liquid separation tank 15 is controlled to be increased. The first water supply path 41 is provided with a water supply valve 42 that adjusts the water supplied into the first gas-liquid separation tank 15. The first water supply path 41 is provided with a water supply pump (not shown). Further, pure water is used as the water supplied from the first water supply path 41, but water in which oxygen gas is dissolved in advance may be introduced.

  The second water supply path 43 supplies water into the second gas-liquid separation tank 18 from the outside, whereby the second circulating water path 17 and the second gas that are circulating water paths on the cathode side 23 of the water electrolysis stack 21 are provided. The pressure of the liquid separation tank 18 is controlled to be increased. The second water supply path 43 is provided with a water supply valve 44 that adjusts the water supplied into the second gas-liquid separation tank 18. The second water supply path 43 is provided with a water supply pump (not shown). Further, pure water is used as the water supplied from the second water supply path 43, but water in which hydrogen gas is dissolved in advance may be introduced.

  The control device 20 can control the current value and the voltage value to the solid polymer electrolyte membrane 22 of the water electrolysis cell 11 according to the electric power of the power generation device 12 or the charging device 13. Further, the control device 20 can adjust and control the discharge pressures (the number of rotations of the pump motor) of the first circulation pump 31 and the second circulation pump 32 described above, and the opening degrees of the hydrogen control valve 33 and the water discharge valve 36 ( 0 to 100%) can be adjusted and controlled. Furthermore, the control device 20 can adjust and control the opening degree (0 to 100%) of the first water on-off valve 42 and the second water on-off valve 43.

  The circulating water path on the cathode side is provided with hydrogen dissolved amount detection estimating means for detecting or estimating the hydrogen dissolved quantity of water circulating in the second gas-liquid separation tank 18 and the second circulating water path 17. The control device 20 functions as this hydrogen dissolved amount detection estimating means. That is, the pressure of water flowing in the second circulating water path 17 and the current value (hydrogen generation amount) applied to the solid polymer electrolyte membrane 22 of the water electrolysis cell 11 based on calculated values and experimental values in advance. The hydrogen dissolved amount set based on the map may be mapped, and the hydrogen dissolved amount in the circulating water on the cathode side may be obtained using this map. The pressure of water in the second circulating water path 17 may be detected by a pressure sensor (pressure detecting means) or estimated based on a pressure sensor (pressure detecting means) built in the second circulating pump 32. May be. The water pressure may be detected by installing a pressure sensor (pressure detection means) in the second gas-liquid separation tank.

  Then, when the water electrolysis device is started, the control device 20 opens the hydrogen control valve 33 when the hydrogen dissolved amount in the circulating water in the second circulating water passage 17 exceeds a predetermined amount set in advance, and the hydrogen extraction passage. The hydrogen gas is taken out from 19. Specifically, when the hydrogen dissolved amount in the circulating water in the second circulating water path 17 becomes the saturated hydrogen quantity, the control device 20 opens the hydrogen control valve 33 and takes out hydrogen gas from the hydrogen extraction path 19. In this case, since the saturated hydrogen amount in the circulating water varies according to the pressure of the circulating water, the saturated hydrogen amount may be obtained by mapping in advance based on a calculated value or an experimental value.

  In the present embodiment, as described above, the second pressurizing unit that pressurizes the circulating water in the circulating water path on the cathode side is determined by the amount of water supplied from the second water supply path 43, and the second circulating water path 17 and a second water supply valve 44 provided in the second water supply path 43 according to the pressure of the second gas-liquid separation tank 18. In this case, the operating pressure in the second circulating water path 17 is set according to the pressure of the hydrogen gas taken out from the hydrogen extraction path 19 and used. The pressure of the circulating water on the cathode side is preferably set to 0.1 MPa to 80 MPa, more preferably 1 MPa to 80 MPa.

  The first pressurizing means for pressurizing the circulating water in the circulating water path on the anode side is determined by the amount of water supplied from the first water supply path 41, and the first circulating water path 14 and the first gas-liquid separation tank 15 are determined. Is controlled by a first water supply valve 42 provided in the first water supply path 41 in accordance with the pressure. In this case, the first water supply valve 42 is controlled in the same manner as the second water supply valve 44. And in order to stabilize the efficiency of the water electrolysis cell 11, since the pressure of the circulating water supplied to the anode side 23 and the cathode side 24 needs to be set substantially the same, the anode connected with the water electrolysis cell 11 The pressure of the circulating water flowing in the first circulating water path 14 on the side and the second circulating water path 17 on the cathode side is maintained at approximately equal pressure. In this embodiment, the pressure difference between the circulating water on the anode side and the circulating water on the cathode side is controlled to 30 kPa or less.

  Furthermore, in the water electrolysis apparatus of the present embodiment, since the power generation apparatus 12 is a power supply apparatus that uses natural energy, the solid polymer electrolyte membrane of the water electrolysis cell 11 depends on the natural environment during operation of the water electrolysis apparatus. The power (current value) supplied to 22 varies. Therefore, the control device 20 controls the hydrogen extraction unit and the pressure adjustment unit according to the amount of power supplied from the power generation device 12 to the solid polymer electrolyte membrane 22.

  Here, the hydrogen extraction means is a hydrogen control valve 33 provided in the hydrogen extraction path 19, and the pressure adjusting means is provided in the second water supply path 43 capable of adjusting the pressure in the second circulating water path 17. The second water supply valve 44 and the water discharge valve 36 provided in the auxiliary path 34 as a water discharge path. The control device 20 opens and closes at least one of the hydrogen control valve 33, the second water supply valve 44, and the water discharge valve 36 in accordance with the amount of power supplied from the power generation device 12 to the solid polymer electrolyte membrane 22. Control.

  Specifically, the control device 20 controls the opening degree of the hydrogen control valve 33 according to the amount of power supplied from the power generation device 12 to the solid polymer electrolyte membrane 22, thereby Adjust pressure. In addition, the control device 20 controls the second water supply valve 44 according to the amount of power supplied from the power generation device 12 to the solid polymer electrolyte membrane 22, and the amount of water supplied into the second circulating water path 17. Adjust the pressure by adjusting. Further, the control device 20 controls the water discharge valve 36 according to the amount of power supplied from the power generation device 12 to the solid polymer electrolyte membrane 22, and the water discharged from the second circulating water path 17 to the buffer tank 35. The pressure is adjusted by adjusting the discharge amount.

  In the water electrolysis apparatus of the present embodiment, after the water electrolysis operation in the water electrolysis cell 11 is stopped, the control device 20 keeps the inside of the second circulating water path 17 in a sealed state. That is, the control device 20 stops energization of the water electrolysis cell 11, stops driving the circulation pumps 31 and 32, and closes the hydrogen control valve 33 at the same time, whereby the second circulating water path 17 on the cathode side. Is a closed space.

  Here, the action at the start of the water electrolysis apparatus of the present embodiment will be described based on the time chart of FIG.

  In the start-up operation in the water electrolysis apparatus, as shown in FIG. 2, when the operator inputs the start-up switch of the water electrolysis apparatus at time t1, the control device 20 first has the first and second water supply valves 42, 44 is opened, and water is supplied to the circulating water paths 14 and 17 of the anode and cathode of the water electrolysis cell 11 through the first and second water supply paths 41 and 43. At the same time, the circulating water is caused to flow by operating the first circulating pump 31 and the second circulating pump 32. Furthermore, the supply of power to the water electrolysis cell 11 is started, and the electrolytic reaction by the water electrolysis cell 11 is started. At this time, the current density supplied to the water electrolysis cell 11 is set higher than the steady current density. The control device 20 closes the hydrogen extraction passage 19 with the hydrogen control valve 33 so that the second circulating water passage 17 is in a sealed state. The control device 20 controls the flow rate of the circulating water by the first circulation pump 31 and the second circulation pump 32 according to the current supplied to the water electrolysis cell 11.

  By controlling the current value and voltage value to the solid polymer electrolyte membrane 22 by the control device 20, the circulating water on the anode side 23 is electrolyzed by the solid polymer electrolyte membrane 22. That is, when water is supplied to the solid polymer electrolyte membrane 22 on the anode side 23 of the water electrolysis cell 11, a reaction occurs on the anode side 23 of the solid polymer electrolyte membrane 22, and oxygen gas and hydrogen ions are appear. This hydrogen ion is accompanied by water due to the potential difference between the anode side 23 and the cathode side 24, moves from the anode side 23 through the solid polymer electrolyte membrane 22 to the cathode side 24, reacts at the cathode side 24, and reacts with hydrogen. Gas is generated.

  The control device 20 monitors the pressure of the circulating water in the circulating water passages 14 and 17 of the anode and the cathode, and closes the first and second water supply valves 42 and 44 at time t2 when the predetermined electrolytic pressure is reached. Then stop the inflow of water. Note that the pressure of the circulating water in the circulating water paths 14 and 17 is detected by a pressure sensor (not shown).

  In this case, since the pressure of the circulating water in the second circulating water path 17 is higher than the steady pressure, the hydrogen gas easily dissolves in the circulating water. Therefore, the hydrogen gas generated on the cathode side 23 circulates in the second circulating water path 17 in a state where it is dissolved in the circulating water.

  When the generated hydrogen gas dissolves in the circulating water and the hydrogen dissolved amount increases, the hydrogen dissolved amount reaches a saturated state in a predetermined time, and the hydrogen gas does not dissolve in the water any more. Therefore, when the amount of dissolved hydrogen in the circulating water in the second circulating water path 17 exceeds the saturation state at time t3, the control device 20 opens the hydrogen control valve 33. Then, the pressure in the hydrogen extraction path 19 increases, and the hydrogen acquisition amount increases. When the hydrogen acquisition amount exceeds a predetermined amount at time t4, the opening degree of the hydrogen control valve 33 is made constant. Thereby, hydrogen gas of a predetermined amount and a predetermined pressure can be acquired stably.

  Next, the operation during operation of the water electrolysis apparatus of the present embodiment will be described based on the time chart of FIG.

  In the operation in the water electrolysis apparatus, as shown in FIG. 3, the control apparatus 20 gives a standard current value to the solid polymer electrolyte membrane 22 from the power generation apparatus 12 and sets the second circulation pump 32 to a predetermined standard. The hydrogen control valve 33 is controlled so as to maintain a predetermined opening degree by driving at a rotational speed. Therefore, the pressure of the second circulating water path 17 is maintained at a predetermined operating pressure, and the amount of hydrogen dissolved in water is also maintained at a predetermined amount.

  From this state, when the current value supplied from the power generation device 12 to the solid polymer electrolyte membrane 22 decreases at time t11, the control device 20 keeps the rotation speed of the second circulation pump 32 constant, The opening degree of the hydrogen control valve 33 is increased. Then, the pressure of the second circulating water path 17 is reduced from the operating pressure, so that hydrogen dissolved in water is vaporized to generate hydrogen gas, and the amount of dissolved hydrogen is reduced. Therefore, although the amount of hydrogen gas generated by electrolysis by the solid polymer electrolyte membrane 22 is reduced, hydrogen dissolved in water is vaporized and hydrogen gas is generated, so that the hydrogen extraction pressure in the hydrogen extraction path 19 is increased. In addition, the hydrogen acquisition amount does not fluctuate, and hydrogen of a predetermined amount and a predetermined pressure can be continuously acquired.

  When the value of the current supplied from the power generator 12 to the solid polymer electrolyte membrane 22 decreases, the water discharge valve 36 is opened to increase the degree of opening while keeping the degree of opening of the hydrogen control valve 33 constant. May be. In this case, the circulating water in the second circulating water path 17 is discharged to the buffer tank 35 via the auxiliary path 34, whereby the second circulating water path 17 can be decompressed.

  When the current value supplied from the power generation device 12 to the solid polymer electrolyte membrane 22 returns to the steady current value at time t12, the control device 20 decreases the opening of the hydrogen control valve 33 to restore the original constant value. Return to opening. Then, when the pressure of the second circulating water path 17 rises to the operating pressure, the generated hydrogen gas is dissolved in water, and the amount of dissolved hydrogen is increased. Therefore, it is possible to continuously acquire hydrogen of a predetermined amount and a predetermined pressure.

  When the current value supplied from the power generator 12 to the solid polymer electrolyte membrane 22 returns to the steady current value, the water in the buffer tank 35 is supplied to the water circulation path 17 while keeping the opening degree of the hydrogen control valve 33 constant. By returning, the pressure may be increased. Moreover, the water supply valve 44 may be opened to increase the opening while the opening of the hydrogen control valve 33 is kept constant. In this case, the second circulating water path 17 can be boosted by supplying water to the second circulating water path 17 via the second water supply path 43.

  On the other hand, when the current value supplied from the power generation device 12 to the solid polymer electrolyte membrane 22 increases at time t13, the control device 20 keeps the rotation speed of the second circulation pump 32 constant and controls the hydrogen. The opening degree of the valve 33 is decreased. Then, the pressure of the second circulating water path 17 rises from the operating pressure, so that the generated hydrogen gas is further dissolved in water and the amount of dissolved hydrogen is increased. Therefore, although the amount of hydrogen gas generated by electrolysis by the solid polymer electrolyte membrane 22 increases, the pressure of the second circulating water passage 17 increases and the amount of hydrogen gas that can be dissolved increases. The hydrogen extraction pressure and the hydrogen acquisition amount at 19 do not change, and a predetermined amount of hydrogen at a predetermined pressure can be continuously acquired. At this time, as described above, even if the opening of the hydrogen control valve 33 is kept constant and the opening of the water supply valve 44 is adjusted, water is supplied to the second circulating water path 17 to increase the pressure. Good.

  If the current value supplied from the power generation device 12 to the solid polymer electrolyte membrane 22 decreases at time t14 or time t15, the control device 20 keeps the rotation speed of the second circulation pump 32 constant as described above. In this manner, the opening degree of the hydrogen control valve 33 is increased. Then, the pressure of the second circulating water path 17 decreases, so that hydrogen dissolved in water is vaporized to generate hydrogen gas, and the hydrogen dissolved amount decreases. Therefore, although the amount of hydrogen gas generated by electrolysis by the solid polymer electrolyte membrane 22 is reduced, hydrogen dissolved in water is vaporized and hydrogen gas is generated, so that the hydrogen extraction pressure in the hydrogen extraction path 19 is increased. In addition, the hydrogen acquisition amount does not fluctuate, and hydrogen of a predetermined amount and a predetermined pressure can be continuously acquired. At this time, as described above, even if the pressure is reduced by discharging water from the second circulating water path 17 by adjusting the opening of the water discharge valve 36 while keeping the opening of the hydrogen control valve 33 constant. Good.

  As described above, in the water electrolysis apparatus of the present embodiment, the solid electrolyte membrane 22 is divided into the anode 23 and the cathode 24 by the solid polymer electrolyte membrane 22, and the solid polymer electrolyte membrane 22. A power generator 12 that supplies electric power, a second circulating water path 17 that circulates and supplies water to the cathode side of the solid polymer electrolyte membrane 22, and a second that separates hydrogen gas from the water flowing through the second circulating water path 17. A gas-liquid separation tank 18, a hydrogen extraction path 19 having a hydrogen control valve 33 for extracting the separated hydrogen gas, pressure adjusting means for adjusting the pressure in the second circulating water path 17, and a solid polymer from the power generator 12 A control device 20 is provided for controlling the hydrogen control valve 33 and the pressure adjusting means in accordance with the amount of power supplied to the electrolyte membrane 22.

  Therefore, when the amount of power supplied to the solid polymer electrolyte membrane 22 by the power generation device 12 fluctuates, the amount of generated hydrogen gas increases or decreases. At this time, by controlling the hydrogen control valve 33 or the pressure regulating means, The pressure in the two circulating water passages 17 is increased and decreased, and the amount of hydrogen gas dissolved in the water is increased or decreased to increase or decrease the amount of vaporized hydrogen gas. Therefore, as a result, the amount of hydrogen gas taken out from the hydrogen take-out path 19 becomes constant, stable hydrogen gas can be generated, and hydrogen production efficiency can be improved.

  Further, in the water electrolysis apparatus of the present embodiment, the pressure adjusting means is the second water supply path 43 and the second water supply valve 44 that supply water into the second circulating water path 17. Therefore, when the amount of power supplied to the solid polymer electrolyte membrane 22 fluctuates, the second water supply valve 44 is opened, and the water in the second circulating water path 17 is supplied and pressurized by the second water supply path 43. Thus, the amount of hydrogen gas is increased or decreased, the amount of hydrogen gas taken out by the hydrogen extraction path 19 can be made constant, and stable generation of hydrogen gas can be made possible.

  Further, in the water electrolysis apparatus of the present embodiment, the pressure regulating means is an auxiliary path (water discharge path) 34 and a water discharge valve 36 for discharging water from the second circulating water path 17. Accordingly, when the amount of electric power supplied to the solid polymer electrolyte membrane 22 fluctuates, the water discharge valve 36 is opened, and the water in the second circulating water path 17 is discharged to the buffer tank 35 by the auxiliary path 34 to reduce the pressure. Thus, the amount of hydrogen gas is increased or decreased, the amount of hydrogen gas taken out by the hydrogen extraction path 19 can be made constant, and stable hydrogen gas generation can be achieved. Moreover, the pressure in the 2nd circulating water path 12 can be easily adjusted with the existing equipment, the cost increase can be suppressed, the pressure adjustment with high reliability is possible, and the stable Hydrogen gas can be supplied.

  Further, in the water electrolysis apparatus of the present embodiment, the hydrogen extraction path 17 is connected to the second gas-liquid separator 80, the hydrogen control valve 33 is provided in the hydrogen extraction path 17, and the hydrogen control valve 33 is used as a pressurizing means. The control device 20 adjusts the opening degree of the hydrogen control valve 33 according to the amount of power supplied from the power generation device 12 to the solid polymer electrolyte membrane 22. Therefore, when the amount of power supplied to the solid polymer electrolyte membrane 22 fluctuates, the pressure in the second circulating water path 17 increases or decreases by adjusting the opening of the hydrogen control valve 33 to the open side or the close side, The amount of hydrogen gas to be vaporized increases and decreases, the amount of hydrogen gas taken out from the hydrogen take-out path 33 becomes constant, and stable generation of hydrogen gas can be made possible.

  Further, in the water electrolysis apparatus of the present embodiment, the control device 20 opens the hydrogen extraction passage 19 by the hydrogen control valve 33 after setting the hydrogen dissolved amount in the water in the second circulating water passage 17 to the saturated hydrogen amount. Therefore, during operation of the apparatus, when the amount of power supplied to the solid polymer electrolyte membrane 22 fluctuates by maintaining the hydrogen dissolved amount in the water in the second circulating water path 17 at the saturated hydrogen amount, The amount of dissolved hydrogen, that is, the amount of hydrogen gas to be vaporized can be adjusted at an early stage, and the control can be speeded up.

  Moreover, in the water electrolysis apparatus of the present embodiment, the power generation apparatus 12 is a natural energy supply apparatus that supplies electric power obtained by natural energy. Accordingly, hydrogen gas can be generated without adversely affecting the global environment.

  In this case, when the pressure in the second circulating water path 17 is reduced, hydrogen dissolved in water is vaporized to generate hydrogen gas, and the amount of dissolved hydrogen is reduced, so that the electrolysis by the solid polymer electrolyte membrane 22 is performed. Although the amount of hydrogen gas produced by the process is reduced, hydrogen dissolved in water is vaporized to generate hydrogen gas. On the other hand, when the pressure in the second circulating water path 17 rises, the generated hydrogen gas dissolves in water and the amount of hydrogen dissolved increases, so that the amount of hydrogen gas generated by electrolysis by the solid polymer electrolyte membrane 22 is reduced. Although it increases, the amount of hydrogen gas that can be dissolved in water increases. Therefore, the hydrogen extraction pressure and the hydrogen acquisition amount in the hydrogen extraction path 19 do not fluctuate, and hydrogen gas having a predetermined amount and a predetermined pressure can be continuously acquired.

  In addition, an ultrasonic transmitter is provided as a means for dissolving hydrogen, and the ultrasonic transmitter transmits ultrasonic waves to water in the cathode side 24 or water or hydrogen gas in the second circulating water path 17. By vibrating, the generated hydrogen gas may be dissolved in water. Also, as a means for dissolving hydrogen, a high voltage device is provided, and by applying a high voltage to the solid polymer electrolyte membrane with this high voltage device, hydrogen gas bubbles are made into very fine microballoons, and the generated hydrogen Gas may be dissolved in water.

  In the above-described embodiment, the power generation device 12 is a natural energy supply device that supplies power obtained by natural energy. However, the power generation device 12 is not limited to this configuration, and power obtained by artificially obtained energy. It is good also as an electric power supply apparatus which supplies. Even with such a power supply device, the power generation amount may fluctuate, which is effective for the water electrolysis device of the present invention.

  The water electrolysis apparatus according to the present invention enables stable production of hydrogen gas by controlling the hydrogen extraction means and the pressure regulation means according to the power supplied to the solid polymer electrolyte membrane. It can also be applied to a water electrolysis apparatus.

11 Water electrolysis cell 12 Power generator (power supply device)
13 Charging Device 14 First Circulating Water Path 15 First Gas-Liquid Separation Tank (Oxygen Separation Means)
16 Oxygen extraction path 17 Second circulating water path 18 Second gas-liquid separation tank (hydrogen separation means)
19 Hydrogen extraction route (hydrogen extraction means)
20 Control device (control means)
22 Solid polymer electrolyte membrane 23 Anode side 24 Cathode side 31 First circulation pump 32 Second circulation pump 33 Hydrogen control valve (hydrogen extraction means)
36 Water discharge valve (pressure adjusting means)
41 1st water supply path (pressure regulation means)
42 1st water supply valve (pressure regulation means)
43 Second water supply path (pressure adjusting means)
44 Second water supply valve (pressure adjusting means)

Claims (6)

A water electrolysis cell whose interior is divided into an anode side and a cathode side by a solid polymer electrolyte membrane;
A power supply device for supplying power to the solid polymer electrolyte membrane;
A first circulating water passage for circulating water to the anode side solid polymer electrolyte membrane side;
A second circulating water path for circulating and supplying water to the cathode side solid polymer electrolyte membrane side;
Hydrogen separation means for separating hydrogen gas from water flowing through the second circulating water path;
Hydrogen extraction means for extracting hydrogen gas separated by the hydrogen separation means from the second circulating water path;
Pressure adjusting means for adjusting the pressure in the second circulating water path;
Control means for controlling the hydrogen extraction means and the pressure regulating means according to the amount of power supplied from the power supply device to the solid polymer electrolyte membrane;
A water electrolysis apparatus comprising:   2. The water electrolysis apparatus according to claim 1, wherein the pressure adjusting unit includes a second water supply path for supplying water into the second circulating water path.   2. The water electrolysis apparatus according to claim 1, wherein the pressure adjusting unit has a water discharge path for discharging water from the second circulating water path.   The hydrogen extraction means has a hydrogen extraction path connected to the hydrogen separation means, and a hydrogen control valve provided in the hydrogen extraction path, the control means from the power supply device to the solid polymer electrolyte membrane The water electrolysis apparatus according to claim 1, wherein an opening degree of the hydrogen control valve is adjusted in accordance with an amount of electric power supplied to the battery.   5. The water electrolysis according to claim 1, wherein the control unit operates the hydrogen extraction unit after setting a hydrogen dissolved amount in water in the cathode-side water circulation path to a saturated hydrogen amount. apparatus.   The water electrolysis apparatus according to any one of claims 1 to 5, wherein the power supply apparatus includes a natural energy supply apparatus that supplies electric power obtained by natural energy.

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