JP2007023343A - Apparatus for producing high-pressure hydrogen - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an apparatus for producing high-pressure hydrogen, which prevents a solid electrolyte of a polymer membrane from being separated from a cathode-side feed body by high-pressure hydrogen gas, and thereby shows excellent electrolytic efficiency while having a simple structure. <P>SOLUTION: This production apparatus comprises a high-pressure vessel 14 provided with a first chamber 15 which accommodates a water electrolysis cell 7 for generating high-pressure hydrogen gas in a cathode side by electrolyzing water supplied to the anode side, and a second chamber 18 which communicates with the first chamber 15; an intercepting member 19 which is arranged on a border between the first chamber 15 and the second chamber 18, intercepts both chambers while making the border watertight, and is formed so as to move back and forth in a direction to the water electrolysis cell 7; a hydrogen-gas-compressing means 25 which is arranged between the water electrolysis cell 7 and the intercepting member 19, and compresses one part of the high-pressure hydrogen gas obtained in the cathode side of the water electrolysis cell 7 into higher-pressure hydrogen gas; and a hydrogen gas guideway 30 for guiding the higher-pressure hydrogen gas compressed by the hydrogen-gas-compressing means 25 to the second chamber 18 therethrough. The higher-pressure hydrogen gas pressurizes the intercepting member 19 toward the water electrolysis cell 7. The hydrogen gas compressing means 25 is a hydrogen membrane pump. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a high-pressure hydrogen production apparatus that produces high-pressure hydrogen gas by electrolysis of water.

  Conventionally, as in the high-pressure hydrogen production apparatus 41 shown in FIG. 4, the solid polymer electrolyte membrane 2, the cathode-side power feeding body 3, the anode-side power feeding body 4 provided opposite to each other, and the power feeding bodies 3. , 4 and a cathode cell separator 5 and an anode separator 6 are provided as a single cell, and a plurality of water electrolysis cells 7 are laminated. In the water electrolysis cell 7, the solid polymer electrolyte membrane 2 includes a catalyst electrode layer (not shown) on both sides.

  The laminated water electrolysis cell 7 is sandwiched between end plates 43 and 43 via insulating members 42 and 42 from both sides, and nuts 45 are screwed onto bolts 44 inserted into the end plates 43 and 43. It is fixed by tightening. As a result, the power feeders 3 and 4 and the separators 5 and 6 are pressed against the solid polymer electrolyte membrane 2.

  In the high-pressure hydrogen production apparatus 41, water is supplied from the water supply port 11 to the fluid passage 10 of the anode-side separator 6 in a state where the power feeders 3 and 4 and the separators 5 and 6 are pressed against the solid polymer electrolyte membrane 2. When the power feeding bodies 3 and 4 are energized, water supplied to the fluid passage 10 is electrolyzed at the catalyst electrode layer on the anode side of the solid polymer electrolyte membrane 2 to generate hydrogen ions, electrons and oxygen gas. To do. The generated hydrogen ions permeate the solid polymer electrolyte membrane 2 due to the potential difference between the power feeders 3 and 4, move to the cathode side, and generate hydrogen gas by receiving electrons from the catalyst electrode layer on the cathode side. The hydrogen gas passes through the porous power supply 3 and moves to the fluid passage 8 of the cathode separator 5, and high-pressure hydrogen gas can be obtained in the fluid passage 8.

  The high-pressure hydrogen gas is taken out from a hydrogen take-out passage 9 communicating with the fluid passage 8. The oxygen generated on the anode side of the solid polymer electrolyte membrane 2 is discharged together with water from the drain port 12 communicating with the fluid passage 10.

  By the way, in the high pressure hydrogen production apparatus 41, when the pressure of the hydrogen gas generated in the fluid passage 8 of the cathode separator 5 increases, the solid polymer electrolyte membrane 2 and the anode power feeder 4 are compressed in the direction of the anode separator 6. There may be a gap between the cathode-side power feeder 3 and the solid polymer electrolyte membrane 2. When the gap is formed, the contact resistance between the cathode-side power feeder 3 and the solid polymer electrolyte membrane 2 is increased, the electrolysis voltage is increased, or the hydrogen gas leaks from the gap, resulting in a decrease in electrolysis efficiency. To do.

  Therefore, a cylinder chamber (not shown) is provided on the anode side of the high-pressure hydrogen production apparatus 41, and a piston (not shown) disposed in the cylinder chamber is subjected to water electrolysis by the pressure of the fluid introduced into the cylinder chamber. There is known one that is pressed in the direction of the cell 7 to prevent separation between the cathode-side power feeder 3 and the solid polymer electrolyte membrane 2 (see, for example, Patent Document 1).

However, in the above configuration, in order to press the piston disposed in the cylinder chamber in the direction of the water electrolysis cell 7, the pressure of the fluid introduced into the cylinder is generated in the fluid passage 8 of the cathode side separator 5. Therefore, there is a disadvantage that a device for increasing the pressure of the fluid is required separately.
JP 2003-160891 A

  The present invention eliminates such inconvenience, prevents separation of the solid polymer electrolyte membrane and the cathode-side power feeder by high-pressure hydrogen gas, and provides high-performance hydrogen production with a simple configuration capable of obtaining excellent electrolysis efficiency. An object is to provide an apparatus.

  In order to achieve this object, the present invention provides a solid polymer electrolyte membrane, a cathode-side power feeder provided opposite to both sides of the solid polymer electrolyte membrane, an anode-side power feeder, and each power-feeder. A cathode-side separator, an anode-side separator, and a fluid passage provided in each separator and exposing each power supply body, supplying water to the fluid passage of the anode-side separator and energizing each power supply body. Thus, in a high-pressure hydrogen production apparatus comprising a water electrolysis cell that electrolyzes water supplied to the fluid passage of the anode-side separator and obtains high-pressure hydrogen gas in the fluid passage of the cathode-side separator, the water electrolysis cell is A high-pressure vessel comprising a first chamber for housing and a second chamber communicating with the first chamber on the anode side of the water electrolysis cell; and both chambers provided at the boundary between the first chamber and the second chamber. Watertight A blocking member provided to be movable in the direction of the water electrolysis cell along the inner wall of the second chamber, and a fluid passage of the cathode separator provided between the water electrolysis cell and the blocking member A part of the high-pressure hydrogen gas obtained in the above, and compressing the hydrogen gas to obtain a higher-pressure hydrogen gas; and a higher-pressure hydrogen gas compressed by the hydrogen gas compression means And a hydrogen gas guide path that guides the blocking member toward the water electrolysis cell with a higher-pressure hydrogen gas guided through the hydrogen gas guide path. .

  In the high-pressure hydrogen production apparatus of the present invention, in the water electrolysis cell accommodated in the first chamber in the high-pressure vessel, water is supplied to the fluid passage of the anode-side separator and each power feeding body is energized, and the anode-side separator Electrolysis of the water supplied to the fluid passage generates hydrogen ions, electrons, and oxygen gas. The generated hydrogen ions permeate the solid polymer electrolyte membrane to the cathode side due to the potential difference between the two feeders, and generate hydrogen gas by receiving electrons on the cathode side. As a result, high-pressure hydrogen gas can be obtained in the fluid passage of the cathode separator of the water electrolysis cell.

  Here, the high-pressure vessel includes a first chamber that houses the water electrolysis cell, and a second chamber that communicates with the first chamber on the anode side of the water electrolysis cell, and both chambers are located at the boundary between the two chambers. Is shut off in a watertight manner, and is provided with the shut-off member that can be moved back and forth in the direction of the water electrolysis cell along the inner wall of the second chamber. Further, the hydrogen gas compression means is provided between the water electrolysis cell and the blocking member.

  Therefore, a portion of the high-pressure hydrogen gas obtained in the fluid passage of the cathode separator of the water electrolysis cell is fractionated and compressed by the hydrogen gas compression means, and the compressed hydrogen gas is supplied to the hydrogen gas guide. Guide to the second chamber through the road. Since the pressure of the hydrogen gas guided to the second chamber is compressed by the hydrogen gas compression means, the pressure of the hydrogen gas obtained in the fluid passage of the cathode separator of the water electrolysis cell is higher. . As a result, the hydrogen gas guided to the second chamber presses the blocking member in the direction of the water electrolysis cell against the pressure of the hydrogen gas obtained in the fluid passage of the cathode separator of the water electrolysis cell. be able to.

  As described above, according to the high-pressure hydrogen production apparatus of the present invention, the hydrogen gas compression means provided in the high-pressure vessel allows the cathode of the water electrolysis cell to be provided without a separate device for generating a high-pressure fluid. The blocking member can be pressed in the direction of the water electrolysis cell by a simple configuration in which a part of the hydrogen gas obtained in the fluid passage of the side separator is separated and compressed. Therefore, even if the pressure of the generated hydrogen gas increases, there is no gap between the solid polymer electrolyte membrane and the cathode-side power feeder, and the electrolysis voltage increases or the generated hydrogen gas leaks. It is possible to obtain an excellent electrolytic efficiency.

  In the high-pressure hydrogen production apparatus of the present invention, the hydrogen gas compression means includes a solid polymer electrolyte membrane, a cathode side power supply provided opposite to both sides of the solid polymer electrolyte membrane, an anode side power supply, A cathode-side separator laminated on each power supply body; an anode-side separator; and a fluid passage provided in each separator and exposing each power-supply body. The fluid passage of the anode-side separator includes a cathode of the water electrolysis cell. Supplying a part of the high-pressure hydrogen gas obtained in the fluid passage of the side separator and energizing each power supply to ionize the high-pressure hydrogen gas and permeate the solid polymer electrolyte membrane, It is a hydrogen membrane pump that obtains higher-pressure hydrogen gas in the fluid passage of the side separator.

  According to the hydrogen membrane pump, when supplying a part of the high-pressure hydrogen gas obtained in the fluid passage of the cathode separator of the water electrolysis cell to the fluid passage of the anode separator and energizing each power feeder, The hydrogen gas is ionized and the generated hydrogen ions permeate the solid polymer electrolyte membrane to the cathode side due to the potential difference between the two power feeders. And the said hydrogen ion produces | generates hydrogen gas again by receiving an electron by the cathode side. As a result, in the hydrogen membrane pump, hydrogen gas having a pressure higher than that of the high-pressure hydrogen gas supplied to the fluid passage of the anode-side separator can be obtained in the fluid passage of the cathode-side separator.

  In the hydrogen membrane pump, the anode separator is preferably laminated on the anode separator of the water electrolysis cell via an insulating member. By doing so, the anode separator of the hydrogen membrane pump is disposed on the water electrolysis cell side, and the positions of both are close to each other. Further, the cathode separator of the hydrogen membrane pump is disposed on the second chamber side, and the positions of both are close to each other.

  Accordingly, a part of the high-pressure hydrogen gas obtained in the fluid passage of the cathode separator of the water electrolysis cell is fractionated and supplied to the fluid passage of the anode separator of the hydrogen membrane pump. The configuration for guiding the hydrogen gas obtained in the fluid passage of the cathode separator to the second chamber can be simplified.

  By the way, in the water electrolysis cell, hydrogen ions generated by electrolysis of water supplied to the fluid passage of the anode separator pass through the solid polymer electrolyte membrane together with water molecules. The high-pressure hydrogen gas obtained in the fluid passage of the cathode separator of the cell contains moisture. As a result, in order to industrially use the hydrogen gas, it is necessary to gas-liquid separate the hydrogen gas and water.

  Therefore, in the high-pressure hydrogen production apparatus of the present invention, the high-pressure vessel includes a third chamber for gas-liquid separation of high-pressure hydrogen gas and water obtained in the fluid passage of the cathode-side separator of the water electrolysis cell, The third chamber is characterized in that it communicates with the first chamber via a hydrogen gas extraction path for extracting high-pressure hydrogen gas from the fluid passage. The gas-liquid separation may be performed by taking out the high-pressure hydrogen gas from the fluid passage of the cathode separator of the water electrolysis cell to the outside of the high-pressure hydrogen production apparatus. By providing the third chamber for performing the above, the apparatus configuration can be simplified.

  Next, embodiments of the present invention will be described in more detail with reference to the accompanying drawings. FIG. 1 is an explanatory cross-sectional view showing the configuration of the high-pressure hydrogen production apparatus of the present embodiment, FIG. 2 is a graph showing the relationship between the hydrogen gas pressure obtained by the high-pressure hydrogen production apparatus and the electrolysis voltage, and FIG. It is a graph which shows the time-dependent change of the electrolysis voltage when electrolyzing regularly with an apparatus.

  As shown in FIG. 1, the high-pressure hydrogen production apparatus 1 of the present embodiment includes a solid polymer electrolyte membrane 2, cathode-side power feeders 3, anode-side power feeders 4 provided opposite to each other, A water electrolysis cell 7 comprising a cathode side separator 5 and an anode side separator 6 respectively laminated on the power feeding bodies 3 and 4 is provided. In the water electrolysis cell 7, the cathode side feeder 3 and the cathode separator 5 are above the solid polymer electrolyte membrane 2, and the anode side feeder 4 and the anode side separator 6 are below the solid polymer electrolyte membrane 2, respectively. Are stacked. The cathode-side separator 5 includes a fluid passage 8 in which the cathode-side power feeder 3 is exposed, and a hydrogen extraction passage 9 that communicates with the fluid passage 8. The anode-side separator 6 is a fluid in which the anode-side power feeder 4 is exposed. A passage 10, a water supply port 11 that communicates with one end of the fluid passage 10, and a drain port 12 that communicates with the other end of the fluid passage 10 are provided.

  In the high-pressure hydrogen production apparatus 1, the water electrolysis cell 7 is a single cell, and two water electrolysis cells 7 are laminated to form a two-layer water electrolysis stack 13, and one water electrolysis cell is formed in the water electrolysis stack 13. The anode separator 6 of the other water electrolysis cell 7 is laminated on the cathode separator 5 of the cathode 7. Each of the power feeding bodies 3 and 4 is energized through the separators 5 and 6, respectively. As described above, the cathode separator 5 of one water electrolysis cell 7 is connected to the other water electrolysis cell 7. Since the anode separators 6 are laminated, the water electrolysis cells 7 and 7 are connected in series, which is advantageous.

  The water electrolysis stack 13 is accommodated in the stack chamber 15 (corresponding to the first chamber of the present invention) 15 formed inside the high-pressure vessel 14 via insulators 16 and 17 above and below, The drain port 12 is in communication with the outside through the side wall of the high-pressure vessel 14.

  In the high-pressure vessel 14, a cylinder chamber (corresponding to a second chamber of the present invention) 18 communicates with the lower portion of the stack chamber 15, and both chambers 15, A piston 19 serving as a shut-off member that shuts 18 in a water-tight manner is disposed so as to be movable back and forth in the direction of the water electrolysis stack 13. On the other hand, between the water electrolysis stack 13 and the piston 19, a solid polymer electrolyte membrane 20, an anode side power feeding body 21, a cathode side power feeding body 22 provided opposite to each other, and each power feeding body 21. , 22 are laminated with an anode-side separator 23 and a cathode-side separator 24, which are respectively laminated, via insulators 17, 26.

  In the hydrogen membrane pump 25, the anode-side power feeder 21 and the anode-side separator 23 are above the solid polymer electrolyte membrane 20 (on the water electrolysis stack 13 side), and the cathode-side power feeder 22 and the cathode-side separator 24 are solid polymer electrolyte membranes. 20 are stacked on the lower side (the side opposite to the water electrolysis stack 13). The insulator 26 is disposed between the piston 19 and the cathode separator 24.

  The anode-side separator 23 includes a fluid passage 27 in which the anode-side power feeder 21 is exposed, and a hydrogen introduction path 28 that communicates with the fluid passage 27, and the hydrogen introduction path 28 passes through the insulator 17 to form a water electrolysis stack. 13 hydrogen extraction paths 9 are connected. The cathode separator 24 includes a fluid passage 29 in which the cathode-side power feeding body 22 is exposed, and a hydrogen guide passage 30 communicating with the fluid passage 29. The hydrogen guide passage 30 passes through the insulator 26 and the piston 19. The cylinder chamber 18 is opened. The cylinder chamber 18 is provided with a hydrogen discharge port 31, and the hydrogen discharge port 31 is opened to the atmosphere through an on-off valve (not shown).

  The high-pressure vessel 14 includes a gas-liquid separation chamber (corresponding to a third chamber of the present invention) 33 above the stack chamber 15 via a partition wall 32, and the gas-liquid separation chamber 33 penetrates the partition wall 32. And communicated with the stack chamber 15 through a hydrogen extraction passage 9 provided. The gas-liquid separation chamber 33 is provided with a hydrogen outlet 34 that penetrates the upper wall of the high-pressure vessel 14. The hydrogen outlet 34 opens the open / close valve (not shown) to increase the pressure inside the gas-liquid separation chamber 33. Hydrogen gas can be taken out freely. Further, the gas-liquid separation chamber 33 is provided with a gas-liquid separation water drainage port 35 penetrating the side wall of the high-pressure vessel 14, and the gas-liquid separation water drainage port 35 is opened by opening an on-off valve (not shown). The gas-liquid separation water W in the separation chamber 33 can be drained freely.

In the high-pressure hydrogen production apparatus 1, the solid polymer electrolyte membranes 2 and 20 are cation permeable membranes, and for example, Nafion (registered trademark, manufactured by DuPont), Aciplex (trade name, manufactured by Asahi Kasei Co., Ltd.) and the like can be used. . The solid polymer electrolyte membranes 2 and 20 include, for example, an electrode catalyst layer (not shown) containing a RuIrFeO _X catalyst on the anode side, and an electrode catalyst layer (not shown) containing a platinum catalyst, for example, on the cathode side. ing.

  The cathode side power feeding bodies 3 and 22 and the anode side power feeding bodies 4 and 21 are formed of, for example, a porous body made of a titanium powder sintered body. Moreover, the cathode side separators 5 and 24 and the anode side separators 6 and 23 are formed of, for example, a titanium plate.

  Next, the operation of the high pressure hydrogen production apparatus 1 of the present embodiment will be described.

  In the initial state, the high-pressure hydrogen production apparatus 1 is in a state in which the power feeders 3 and 4 of the water electrolysis stack 13 and the separators 5 and 6 are pressed against and in close contact with the solid polymer electrolyte membrane 2. In this state, when water is supplied to the fluid passage 10 of the anode separator 6 from the water supply port 11 and the power feeding bodies 3 and 4 are energized, the water supplied to the fluid passage 10 is supplied to the anode side of the solid polymer electrolyte membrane 2. The catalyst electrode layer is electrolyzed to generate hydrogen ions, electrons, and oxygen gas. The hydrogen ions permeate the solid polymer electrolyte membrane 2 due to the potential difference between the power feeders 3 and 4 and move to the cathode side, receive electrons from the cathode-side catalyst electrode layer, and become hydrogen gas. The hydrogen gas passes through the power feeder 3 and moves to the fluid passage 8 of the cathode separator 5, and high-pressure hydrogen gas is obtained in the fluid passage 8.

  By the way, as the electrolysis progresses, the pressure of the hydrogen gas obtained in the fluid passage 8 of the cathode separator 5 of each water electrolysis cell 7 gradually increases, and the solid polymer electrolyte membrane 2 and the anode power supply 4 are connected to the anode. There is a concern that a gap is formed between the cathode side power feeder 3 and the solid polymer electrolyte membrane 2 by being compressed in the direction of the side separator 6.

  At this time, in the high-pressure hydrogen production apparatus 1, a part of the high-pressure hydrogen gas obtained in the fluid passage 8 is separated, and from the hydrogen introduction passage 28 connected to the hydrogen extraction passage 9, the anode of the hydrogen membrane pump 25. It is introduced into a fluid passage 27 provided in the side separator 23. In the hydrogen membrane pump 25, the power supplied to the power feeding bodies 21 and 22 is ionized so that the hydrogen supplied to the fluid passage 27 is ionized by the catalyst electrode layer on the anode side of the solid polymer electrolyte membrane 20, and the generated hydrogen ions are fed to the power feeding body. Due to the potential difference between 21 and 22, it passes through the solid polymer electrolyte membrane 20 and moves to the cathode side. The hydrogen ions are obtained in the fluid passage 29 of the cathode separator 24 and in the fluid passage 8 of the cathode separator 5 of each water electrolysis cell 7 by receiving electrons from the catalyst electrode layer on the cathode side and becoming hydrogen gas. Hydrogen gas having a higher pressure than hydrogen gas can be obtained. The high-pressure hydrogen gas obtained in the fluid passage 29 is guided to the cylinder chamber 18 through the hydrogen guide path 30.

  Since the high-pressure hydrogen gas obtained in the fluid passage 29 is higher in pressure than the hydrogen gas obtained in the water electrolysis stack 13 as described above, when the hydrogen gas is guided to the cylinder chamber 18, the piston 19 It is pressed to the electrolytic stack 13 side. Accordingly, in the water electrolysis stack 13, the power feeders 3, 4 of each water electrolysis cell 7 and the separators 5, 6 are the pressure of hydrogen gas obtained in the fluid passage 8 of the cathode side separator 5 of each water electrolysis cell 7. The solid polymer electrolyte membrane 2 is pressed against this, and the state of being in close contact with the solid polymer electrolyte membrane 2 is maintained.

  As a result, in the high-pressure hydrogen production apparatus 1, even when the electrolysis proceeds and the pressure of hydrogen gas obtained in the fluid passage 8 of the cathode separator 5 of each water electrolysis cell 7 increases, There is no gap between the solid polymer electrolyte membrane 2. Therefore, in the high-pressure hydrogen production apparatus 1, it is possible to obtain an excellent electrolysis efficiency by preventing the electrolysis voltage from increasing or the hydrogen gas from leaking from the gap.

  In the high-pressure hydrogen production apparatus 1, an electrolytic power source for the power feeders 3, 4 of the water electrolysis stack 13 and a hydrogen membrane pump power source for the power feeders 21, 22 of the hydrogen membrane pump 25 are provided independently. Is preferred. In this case, while controlling the electrolysis power arbitrarily, the pressure of the hydrogen gas obtained in the fluid passage 8 of the cathode separator 5 of each water electrolysis cell 7 and the pressure of the hydrogen gas in the cylinder chamber 18 are detected. To adjust the voltage of the hydrogen membrane pump power supply.

  By doing in this way, the pressure of the hydrogen gas in the cylinder chamber 18 can be made higher than the pressure of the hydrogen gas obtained in the fluid passage 8 of the cathode-side separator 5 of each water electrolysis cell 7. In the high-pressure hydrogen production apparatus 1, the pressure of the hydrogen gas in the cylinder chamber 18 is set to be 2 to 15 MPa higher than the pressure of the hydrogen gas obtained in the fluid passage 8 of the cathode separator 5 of each water electrolysis cell 7. Preferably, it is further preferable to increase the pressure by 5 to 10 MPa.

  At this time, the voltage E of the hydrogen film pump power source required to move the hydrogen gas from the anode side to the cathode side is expressed by the following equation (1).

E = (RT / 2F) ln (p ₁ / p ₂ ) + resistance loss voltage (1)
In the formula (1), R is a gas constant (8.3145 J / K · mol), T is the temperature (K) of the water electrolysis stack 13, F is the Faraday constant (96485 C / mol), and p ₁ is the high pressure side (cylinder chamber) 18 side) pressure, p ₂ is a low pressure side (water electrolysis stack 13 side) pressure. As is clear from the equation (1), as the pressure of the hydrogen gas obtained in the water electrolysis stack 13 increases, the voltage E of the hydrogen membrane pump power source required to move the hydrogen gas from the anode side to the cathode side decreases. It is advantageous.

  On the other hand, in each water electrolysis cell 7, the hydrogen ions generated in the fluid passage 10 of the anode side separator 6 permeate the solid polymer electrolyte membrane 2 with water molecules, and thus are obtained in the fluid passage 8 of the cathode side separator 5. The high-pressure hydrogen gas produced contains moisture. Therefore, in the high-pressure hydrogen production apparatus 1, the hydrogen gas is introduced into the gas-liquid separation chamber 33 through the hydrogen take-out passage 9 communicating with the fluid passage 8 to perform gas-liquid separation. The hydrogen gas introduced into the gas-liquid separation chamber 33 is gas-liquid separated by the action of gravity, and the gas-liquid separation water W is stored at the bottom of the gas-liquid separation chamber 33, while the gas-liquid separation water W is located above the gas-liquid separation water W. Stores high-pressure hydrogen gas. At this time, the on-off valves (not shown) provided at the hydrogen outlet 21 and the gas-liquid separation water drain 22 are all closed.

  In the high-pressure hydrogen production apparatus 1, since the gas-liquid separation chamber 33 is provided above the stack chamber 15, the gas-liquid separation water W is separated from the cathode side of each water electrolysis cell 7 via the hydrogen outlet 9 by gravity. It is supplied to the fluid passage 8 of the separator 5. The gas-liquid separated water W penetrates the cathode-side power feeder 3 exposed in the fluid passage 8 and covers the cathode-side surface of the solid polymer electrolyte membrane 2 with a water layer (not shown). As a result, the hydrogen gas generated in the fluid passage 8 of the cathode separator 5 is blocked by the water layer and cannot come into contact with the solid polymer film 2, and the hydrogen gas passes through the solid polymer film 2. Leakage to the anode side can be prevented.

  In the high-pressure hydrogen production device 1, when the electrolysis of water proceeds and the hydrogen gas pressure obtained in the fluid passage 8 of the cathode-side separator 5 is high, the electrolysis is stopped in the cylinder chamber 18. The pressure of the hydrogen gas is also maintained higher than the pressure of the hydrogen gas obtained in the fluid passage 8 of the cathode side separator 5. On the other hand, when the pressure of the hydrogen gas in the cylinder chamber 18 is released, the open / close valve (not shown) provided in the hydrogen outlet 21 is opened to be stored in the gas-liquid separation chamber 33. High-pressure hydrogen gas is extracted as a product.

  Next, when the high pressure hydrogen production apparatus 1 starts electrolysis of water from normal pressure and gradually increases the pressure of the hydrogen gas obtained in the fluid passage 8 of the cathode side separator 5, the hydrogen membrane pump 25 is operated. The change of the electrolysis voltage was measured in the case of being operated (Example) and in the case of not being operated (Comparative Example). When operating the hydrogen membrane pump 25, the voltage of the hydrogen membrane pump power supply was controlled so that the pressure of the hydrogen gas in the cylinder chamber 18 was 5 MPa higher than the pressure of the hydrogen gas obtained in the water electrolysis stack 13. The results are shown in FIG.

  From FIG. 2, when the hydrogen membrane pump 25 is not operated, the electrolysis voltage sharply increases as the pressure of the hydrogen gas obtained in the fluid passage 8 of the cathode separator 5 increases, compared to the hydrogen membrane pump 25. It is clear that the increase of the electrolysis voltage can be suppressed when the is operated.

Next, in a steady state where the temperature of the water electrolysis stack 13 is 30 ° C., the current density in the power feeders 3 and 4 is 1 A / cm ² , and the hydrogen gas pressure obtained in the fluid passage 8 of the cathode separator 5 is 35 MPa. Then, the voltage of the hydrogen membrane pump power source was controlled so that the pressure of the hydrogen gas in the cylinder chamber 18 was 40 MPa, water was electrolyzed, and the change over time in the electrolysis voltage was measured. At this time, the voltage of the hydrogen membrane pump power supply was about 100 mV. The results are shown in FIG.

  From FIG. 3, it is apparent that the electrolysis voltage can be maintained substantially constant by operating the hydrogen membrane pump 25 in the steady state.

BRIEF DESCRIPTION OF THE DRAWINGS Explanatory sectional drawing which shows one Embodiment of the high pressure hydrogen production apparatus of this invention. The graph which shows the relationship between the pressure of the hydrogen gas obtained with a high pressure hydrogen production apparatus, and an electrolysis voltage. The graph which shows the time-dependent change of the electrolysis voltage when performing electrolysis regularly with a high pressure hydrogen production apparatus. Explanatory sectional drawing which shows the example of 1 structure of the conventional high pressure hydrogen production apparatus.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... High pressure hydrogen production apparatus, 2,20 ... Solid polymer electrolyte membrane, 3,22 ... Cathode side electric power feeding body, 4,21 ... Anode side electric power feeding body, 5,24 ... Cathode side separator, 6,23 ... Anode side separator 7 ... Water electrolysis cell, 8, 10, 27, 29 ... Fluid passage, 9 ... Hydrogen extraction path, 14 ... High pressure vessel, 15 ... First chamber, 18 ... Second chamber, 19 ... Shut-off member, 25 ... Hydrogen gas Compression means (hydrogen membrane pump), 33 ... third chamber.

Claims (4)

Solid polymer electrolyte membrane, cathode-side power feeder provided opposite to each other on both sides of the solid polymer electrolyte membrane, anode-side power feeder, cathode-side separator laminated on each power-feed body, and anode-side separator And a fluid passage that is provided in each separator and exposes each power supply body, and supplies water to the fluid passage of the anode side separator and supplies the fluid to the fluid path of the anode side separator by energizing each power supply body. In a high-pressure hydrogen production apparatus comprising a water electrolysis cell that electrolyzes the produced water and obtains high-pressure hydrogen gas in the fluid passage of the cathode-side separator,
A high-pressure vessel comprising a first chamber containing the water electrolysis cell, and a second chamber communicating with the first chamber on the anode side of the water electrolysis cell;
A blocking member provided at the boundary between the first chamber and the second chamber to block both chambers in a water-tight manner and to be capable of moving forward and backward in the direction of the water electrolysis cell along the inner wall of the second chamber;
A portion of the high-pressure hydrogen gas that is provided between the water electrolysis cell and the blocking member and is obtained in the fluid passage of the cathode-side separator is fractionated, and the hydrogen gas is compressed to generate higher-pressure hydrogen gas. Obtaining hydrogen gas compression means;
A hydrogen gas guide path for guiding the higher pressure hydrogen gas compressed by the hydrogen gas compression means to the second chamber,
An apparatus for producing high-pressure hydrogen, wherein the blocking member is pressed in the direction of the water electrolysis cell by higher-pressure hydrogen gas guided through the hydrogen gas guide path.   The hydrogen gas compression means includes a solid polymer electrolyte membrane, a cathode-side power feeder provided opposite to both sides of the solid polymer electrolyte membrane, an anode-side power feeder, and a cathode laminated on each power feeder A side separator, an anode separator, and a fluid passage that is provided in each separator and exposes each power supply body. The fluid passage of the anode separator is obtained in the fluid passage of the cathode separator of the water electrolysis cell. By supplying a part of the high-pressure hydrogen gas and energizing each power supply body, the high-pressure hydrogen gas is ionized and permeated through the solid polymer electrolyte membrane, and a higher-pressure hydrogen gas is passed through the fluid path of the cathode-side separator. 2. The high-pressure hydrogen production apparatus according to claim 1, wherein the high-pressure hydrogen production apparatus is a hydrogen membrane pump for obtaining hydrogen gas.   The high-pressure hydrogen production apparatus according to claim 2, wherein the hydrogen membrane pump has the anode separator laminated on the anode separator of the water electrolysis cell via an insulating member.   The high-pressure vessel includes a third chamber for gas-liquid separation of the high-pressure hydrogen gas obtained in the fluid passage of the cathode separator of the water electrolysis cell and water, and the third chamber is separated from the fluid passage by high-pressure hydrogen. The high-pressure hydrogen production apparatus according to any one of claims 1 to 3, wherein the high-pressure hydrogen production apparatus is communicated with the first chamber through a hydrogen take-out path for taking out a gas.

Images