JP4010193B2 - High pressure hydrogen production equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  This invention uses high-pressure hydrogen (compressed hydrogen) that is required for the use of hydrogen energy, etc. without using a mechanical booster such as a compressor by electrolyzing pure water using a solid polymer electrolyte membrane. Gas) directly relates to a high-pressure hydrogen production apparatus, and belongs to a technology related to hydrogen clean energy.
[0002]
[Prior art]
  In order to use fossil fuels such as coal and oil as energy, carbon dioxide emitted during use can cause global warming, and nitrogen oxides and sulfur oxides can damage human health and cause acid rain. There is a problem that causes it to fallTo do.
  AlsoHowever, since fossil fuels have limited reserves, there are more fundamental problems of exhaustion sooner or later, so in order to suppress the occurrence of these problems, fossil fuel consumption is suppressed or stopped, There is a need for the development of technology to use clean natural energy that can replace fuel and can be regenerated.
[0003]
  The largest renewable energy alternative to fossil fuels is solar energy.The
  HoweverThe hour's energy that the earth receives from the sun is comparable to the energy of more than a year that human beings consume today, and solar energy alone is not a dream to meet human energy needs. .
[0004]
  In addition, solar power generation, wind power generation, hydroelectric power generation, etc. are well known as typical usage forms of natural energy.Yes.
  Although natural energy is generally taken out as electric power, it is difficult to store and carry electric power, and there is a method of charging the battery as a method of storing electric power, but the battery is heavy and used by self-discharge. There is a problem such as exhaustion even when not.
[0005]
  Therefore, the most important thing for energy in the future is that it can be stored and easily carried, and it can be widely used at the necessary place when needed. It can be stored by converting it into clean hydrogen energy by (water electrolysis), and this hydrogen can be used as an energy alternative to petroleum. It is said that the 21st century will become a hydrogen economy society using hydrogen as energy. ing.
[0006]
  In order to make such a hydrogen economy society, it is necessary to be able to use hydrogen efficiently as energy.
  As a means for this, the development of fuel cells using hydrogen as fuel (hereinafter referred to as PEFC) will be promoted, and it will be widely used in automobiles and private power generation for home use, and hydrogen produced using natural energy can be used as fuel. Therefore, it is thought that a hydrogen economy society without fear of global warming due to carbon dioxide can be realized. As a precondition, it is considered that producing hydrogen efficiently with natural energy is an important issue.
[0007]
  As a method for efficiently producing hydrogen by natural energy, water is more efficiently used than the known alkaline water electrolysis in which a porous membrane such as gas-permeable asbestos is used as a diaphragm for separating a cathode and an anode. In addition to being able to convert to hydrogen, start and stop can be performed freely, and hydrogen can be produced without problems even from highly fluctuating power generated by natural energy. Water electrolysis (hereinafter referred to as PEM water electrolysis) using a solid polymer electrolyte membrane (hereinafter referred to as PEM) that electrolyzes water into hydrogen and oxygen has attracted attention.
[0008]
  However, since hydrogen is a gas, special consideration is required for storage and transportation when used as energy.
  Initially, liquid hydrogen and occlusion alloys were studied as storage methods, but there were problems that could not be solved, such as natural evaporation and occlusion amount. Recently, lightweight and high pressure cylinders were developed. High-pressure hydrogen, which is compressed at a high pressure of 350 atm or higher and filled in a cylinder for storage and transportation, has attracted widespread attention.
[0009]
  In addition, since water electrolysis itself has a pressure-increasing ability, it is not a dream to generate high-pressure hydrogen of 1000 atm or more.
  If high-pressure hydrogen generation by water electrolysis can be realized, maintenance work such as periodic inspection and replacement of consumable parts is not required, and long-term unmaintained unmanned automatic required to convert natural energy into hydrogen Driving can be realized.
  In addition, since there are many advantages such as higher boosting efficiency and less compression power than when using a mechanical booster such as a compressor, much expectation has been gathered for the generation of high-pressure hydrogen for energy by PEM water electrolysis. Yes.
[0010]
  The hydrogen generator by PEM water electrolysis is a water electrolysis in which a plurality of unit cells are formed by sandwiching a PEM having catalyst electrodes such as platinum on both sides with a porous feeder that can secure the passage of pure water or gas. Each unit cell is stacked, and the electrode plate that partitions each unit cell is an anode and also serves as the cathode of the next unit cell. The PEM water electrolysis cell configured as described above can be called a bipolar and stacked water electrolysis cell, and much expectation has been gathered for the appearance of a high-performance high-pressure hydrogen production apparatus using this.
[0011]
  However, this bipolar and stacked water electrolysis cell has a low withstand voltage at present, and the high-pressure hydrogen obtained is high-pressure hydrogen of about several atmospheres to several tens of atmospheres at most 350, which is required for the use of hydrogen energy. In order to generate high-pressure hydrogen at atmospheric pressure or higher, a mechanical pressure booster such as a compressor is required, so the problem of low pressure resistance of water electrolysis cells can be solved, and hydrogen can be used only by electrolysis. The advent of a high-pressure hydrogen generator that can produce the required high-pressure hydrogen has been awaited.
[0012]
  This was first made possible by Patent No. 3,220,607 (patent No. 5,690,797 in the United States), which works on PEMs in bipolar stacked water electrolysis cells. The force is a differential pressure between hydrogen generated at the cathode and oxygen generated at the anode, and the force acting on the seal portion of the water electrolysis cell is the pressure of hydrogen and oxygen in the water electrolysis cell and the water electrolysis cell. Paying attention to the difference in pressure with the outside pressure, the water electrolysis cell is immersed in pure water in the high-pressure vessel that stores pure water and oxygen, and the pressure in the high-pressure vessel that stores hydrogen and water electrolysis The pressure of the water electrolysis cell is controlled by controlling the pressure in the high pressure vessel storing the cell to be equal, and controlling the differential pressure acting on the seal portion of the PEM and the water electrolysis cell within the pressure resistance of the water electrolysis cell. Even if high pressure hydrogen and oxygen are generated, the water electrolysis cell The difference pressure or to avoid the action of the inner, it was to allow the generation of high-pressure hydrogen.
[0013]
  However, in the present invention, since the water electrolysis cell is immersed in pure water, when the quality of pure water is lowered, its specific resistance is lowered, so that leakage between electrodes of the water electrolysis cell becomes a problem. It is necessary to circulate the pure water in which the water electrolysis cell is immersed and continue to regenerate with the ion exchange resin to prevent a decrease in the specific resistance of the pure water, but the pure water in which the water electrolysis cell is immersed has a temperature of 80 ° C. Or, since high pressure of 350 atm or higher acts at a high temperature higher than that, there is no ion exchange resin that can be used under such a high temperature and high pressure, and problems such as leakage due to a decrease in the resistivity of pure water can be solved. There wasn't. Furthermore, when water and high-pressure oxygen coexist, electrolytic corrosion is likely to occur, and it is a problem to install a water electrolysis cell having an electrode in a high-pressure vessel in such an environment. Hydrogen at a pressure of 10 atmospheres or more is stable. However, there are various problems to be solved.
[0014]
  Therefore, in order to prevent a decrease in the specific resistance of pure water and the problem of electrolytic corrosion, JP-A-2001-130901, in which a bipolar and stacked water electrolysis cell is housed in a high-pressure vessel filled with an insulating liquid. However, there are no practical insulating liquids that immerse the water electrolysis cell, and even if they exist, they are artificially synthesized liquids that can be used for groundwater and soil due to leakage. As long as there is a risk of contamination, it was found to be less feasible.
[0015]
  In order to solve these problems, the inventor in hydrogen of a high pressure vessel that stores and separates hydrogen generated at the cathode of the water electrolysis cell and pure water that permeates from the anode accompanying the movement of hydrogen ions. Proposed a high-pressure hydrogen production apparatus (Japanese Patent Application No. 2002-019713) in which a water electrolysis cell is accommodated.
[0016]
  This invention not only solves problems related to electrolytic corrosion and a decrease in the resistivity of pure water all at once, but also pure water sequesters oxygen and hydrogen against anomalies in the device that damage the water electrolysis cell. This prevents the generation of squealing by mixing hydrogen and oxygen, greatly improving safety.
[0017]
[Problems to be solved by the invention]
  However, also in this invention, in order to make the hydrogen generation pressure extremely high, differential pressure control accuracy has been a problem.
  That is, assuming that the differential pressure control accuracy is S (%), the pressure resistance of the water electrolysis cell is Ps, and the pressure of hydrogen (or oxygen) generated from the water electrolysis cell is P, the following equation (1) The relationship shown in exists.
[0018]
    S ≧ (Ps / P) * 100 (1)
[0019]
  From the above equation (1), it can be seen that in order to increase the generated pressure P, either Ps is increased, the differential pressure control accuracy S is made more accurate, or both are required. At present, since the differential pressure control accuracy S is limited, the hydrogen (or oxygen) pressure P that can be generated is ultimately determined by the pressure resistance Ps of the water electrolysis cell.
[0020]
  For example, assuming that S is about 1% and a cell with an allowable withstand pressure of about 4 atm is used, it can be seen from formula (1) that high-pressure hydrogen up to about 400 atm can be generated.
[0021]
  Therefore, although it is possible in principle to generate hydrogen at about 350 atm, which is required for the time being, in order to generate hydrogen at 350 atm more stably and safely, the pressure resistance of the water electrolysis cell is lowered. There is a need to eliminate the factors.
[0022]
  Furthermore, if the generated pressure is increased, the wall thickness of the high-pressure vessel needs to be increased in proportion to the square of the vessel diameter. If the wall thickness is increased, processing and handling are difficult, which is disadvantageous in terms of cost. It is required to make the container diameter as small as possible.
[0023]
  In addition, when hydrogen is used as energy, it is considered that compressed hydrogen of about 700 atm is eventually required, and realization of a high-pressure hydrogen production apparatus that can withstand that is expected.
[0024]
  In view of the present situation, the inventor aims to provide a high-pressure hydrogen production apparatus capable of stably and safely generating high-pressure hydrogen at 350 atm or higher without using a mechanical pressurizing means such as a compressor. Developed as
1) Fastening and fixing the multi-polar, stacked water electrolysis cell by using the bolts provided on the outer periphery of the water electrolysis cell and clamping with the pressing force of the holding member
2) Extraction of hydrogen and permeated pure water generated at the cathode is directly discharged from each cathode of the water electrolysis cell into the hydrogen high-pressure vessel by providing a discharge port communicating with the cathode on the side wall of the cell bipolar electrode. thing,
3) Supplying pure water to be electrolyzed from a pure water supply path formed by a hole provided in the center of the water electrolysis cell;
The inventors have found that the above-mentioned problems can be solved by such means as described above, and have completed the present invention.
[0025]
[Means for Solving the Problems]
  That is, the invention according to claim 1 of the present invention is
  A multi-layer water electrolysis cell is constructed by laminating a plurality of multi-polar electrodes consisting of a solid polymer electrolyte membrane with catalyst layers formed on both sides and a porous power supply in contact with both sides.Shi,
  SaidA water electrolysis cell is installed on a mounting table in a high-pressure vesselWater electrolysis cellTop ofFromHigh pressure vesselOne end of the inner wall is fixed and maintainedBy holding jigAnd sandwich multiple bipolar electrodesHolding in a pressed state
Is a high-pressure hydrogen production apparatus characterized by
[0026]
  The invention according to claim 2
  A multi-layered water electrolysis cell is constructed by laminating a plurality of multi-electrode electrodes composed of a solid polymer electrolyte membrane having a catalyst layer formed on both sides and a porous power supply in contact with both surfaces,
  SaidWater electrolysis cell, high pressure vesselOne end of the inner wall is fixed and maintainedPresser jigUsing a plurality of bipolar electrodesWhile being held in a high-pressure vessel in a clamped state,
  Formed a pure water supply channel at the center of each bipolar electrode
Is a high-pressure hydrogen production apparatus characterized by
[0027]
  Furthermore, the invention described in claim 3
  A multilayer polyelectrolyte water electrolysis cell is constructed by laminating a plurality of multipolar electrodes composed of a solid polymer electrolyte membrane having a catalyst layer formed on both surfaces and a porous power supply in contact with both surfaces,
  SaidWater electrolysis cell, high pressure vesselOne end of the inner wall is fixed and maintainedPresser jigUsing a plurality of bipolar electrodesHeld in a high-pressure vessel in a clamped state,
  SaidA pure water supply channel is provided at the center of each bipolar electrode, and oxygen is supplied to the anode side of each bipolar electrode.And pure waterThe outletRespectivelyProvided,
  These oxygenAnd pure waterAn oxygen discharge path is formed in the vertical direction on the outer periphery of each bipolar electrode so as to be in contact with the discharge port of
  Hydrogen on the cathode sideAnd pure waterProvided a discharge port to discharge the gas directly to the high-pressure vessel
Is a high-pressure hydrogen production apparatus characterized by
[0028]
  The invention according to claim 4 of the present invention is
  In the high pressure hydrogen production apparatus according to any one of claims 1 to 3,
  The bipolar electrode is:
  The shape is disc-shaped
It is characterized by.
[0029]
  The invention according to claim 5 of the present invention is
  In the high pressure hydrogen production apparatus according to any one of claims 1 to 4,
  The solid polymer electrolyte membrane is:
  It is fixed to the bipolar electrode with a sheet-like sealing material provided on its outer periphery.
It is characterized by.
[0030]
  The invention according to claim 6 of the present invention provides
  The high-pressure hydrogen production apparatus according to claim 5,
  The sealing material is
  Thinner than the solid polymer electrolyte membrane, andFrom the electrolyte membraneMust be made of hard material
It is characterized by.
[0031]
  The invention according to claim 7 of the present invention provides
  In the high pressure hydrogen production apparatus according to any one of claims 1 to 3,
  The water electrolysis cell in the pressed state is
  Multiple bipolar electrodesAre arranged in a multistage state
It is characterized by.
[0032]
  The invention according to claim 8 of the present invention provides
  The high-pressure hydrogen production apparatus according to claim 1,
  The mounting table for the water electrolysis cell is:
  Having a pure water supply port for supplying pure water to the pure water supply passage;
It is characterized by.
[0033]
  Further, the claims of the present invention9The invention described in
  Claim 1Any of ~ 3In the high-pressure hydrogen production apparatus described in
  The holding jig is
  It is composed of a jig main body fixed to the upper part of the water electrolysis cell, a spring body mounted in the jig, and a presser screw for biasing the spring body and having one end held in the high-pressure vessel. Being
It is characterized by.
[0034]
  Further, the claims of the present invention10The invention described in
  In the high pressure hydrogen production apparatus according to any one of claims 1 to 3,
  The bipolar electrode is:
  They are stacked in the vertical direction, with the upper surface serving as the anode and the lower surface serving as the cathode.
It is characterized by.
[0035]
  Further, the claims of the present invention11The invention described in
  Claim 1Any of ~ 3In the high-pressure hydrogen production apparatus described in
  The porous feeder is
  It is fixed inside the water electrolysis cell by welding
It is characterized by.
[0036]
  Further, the claims of the present invention12The invention described in
  Claim 1Any of ~ 3In the high-pressure hydrogen production apparatus described in
  The water electrolysis cell is
  The surface of the porous power supply in contact with the solid polymer electrolyte membrane must be polished
It is characterized by.
[0037]
  Further, the claims of the present invention13The invention described in
  Claim 1Any of ~ 3In the high-pressure hydrogen production apparatus described in
  The water electrolysis cell is
  The surface of the porous power supply in contact with the solid polymer electrolyte membrane must be polished and covered with a carbon film.
It is characterized by.
[0038]
  Further, the claims of the present invention14The invention described in
  Claim13In the high-pressure hydrogen production apparatus described in
  The carbon film is
  Formed by ECR plasma deposition method
It is characterized by.
[0039]
DETAILED DESCRIPTION OF THE INVENTION
  Hereinafter, a high-pressure hydrogen production apparatus according to the present invention will be described in detail with reference to the accompanying drawings.
[0040]
  FIG. 1 is a cross-sectional view of a high-pressure hydrogen production apparatus 1 according to an embodiment of the present invention. In the high-pressure hydrogen production apparatus 1, a bipolar and stacked water electrolysis cell 3 is placed in a hydrogen high-pressure vessel 2. Arranged in the direction.
[0041]
  As shown in FIG. 1, this water electrolysis cell 3 is a ring-shaped solid polymer electrolyte in which a catalyst layer made of platinum is formed on both surfaces between a disc-shaped cathode main electrode 4 and an anode main electrode 5. A plurality of ring-shaped bipolar electrodes 7, 7... Composed of a membrane 6 and a porous power supply 11 are laminated with a separation wall 16 interposed between the porous power supply 11 opposed in the vertical direction. The anode main electrode 5 is clamped downward by a holding jig 23 having a pressure applied by a spring body 19 while being placed on a mounting table 17 provided in the hydrogen high-pressure vessel 2.
[0042]
  The holding jig 23 includes a cylindrical jig main body 18 fixed to the upper part of the water electrolysis cell 3, a spring body 19 mounted in the jig main body 18, and the spring body 19. In FIG. 1, only one is shown for the sake of convenience, but in reality, a plurality of them are arranged symmetrically. The water electrolysis cell 3 is uniformly pressed and clamped, and the water electrolysis cell 3 can be clamped by hydraulic pressure in addition to the pressure applied by the spring body 19.
[0043]
  In the water electrolysis cell 3 formed by laminating a plurality of bipolar electrodes 7, through holes 9, 9,... Are formed on the outer periphery of each bipolar electrode 7 so as to communicate with each other in the vertical direction. Then, an oxygen discharge path A was provided, and an oxygen discharge port 12 was formed on the anode side of each bipolar electrode 7 so as to face the oxygen discharge path A, so that it did not electrolyze with the generated oxygen. Pure water is discharged out of the high-pressure vessel 2 through the discharge port 12 → the oxygen discharge path A → the oxygen discharge pipe 42, and the hydrogen discharge port 10 is formed in the radial direction on the cathode side to generate hydrogen generated from the cathode. The pure water that permeates is discharged directly into the high-pressure vessel 2.
[0044]
  Further, in the center of the water electrolysis cell 3, pure water for supplying pure water for electrolysis by through holes 8, 8... Formed at the center of each bipolar electrode 7 so as to communicate with each other in the vertical direction. A pure water supply pipe 47 for supplying pure water from outside the high-pressure vessel 2 is connected to the pure water supply path B, and the pure water formed on the anode side in contact with the pure water supply path B is formed. Pure water is supplied to the porous power supply 11 through the water supply port 8a.
[0045]
  Furthermore, a lead wire 32 for supplying electric power from the outside is coupled to the upper part of the water electrolysis cell 3.
[0046]
  When the solid polymer electrolyte membrane 6 is clamped by the holding jig 23, the pressure is adjusted so that the solid polymer electrolyte membrane 6 is not crushed. Since the polymer electrolyte membrane 6 may be crushed, a sheet-like sealing material 24 formed in a ring shape is disposed on the outer periphery of the solid polymer electrolyte membrane 6, and even if an excessive pressing force is applied, the solid electrolyte membrane 6 is solid. The polymer electrolyte membrane 6 is prevented from being crushed and good sealing characteristics are obtained.
[0047]
  The sealing material 24 is thinner and harder than the solid polymer electrolyte membrane 6 and is formed in a ring shape with a material such as plastic having good electrical insulation. The solid polymer electrolyte membrane 6 Whether or not the thickness relationship between the sealing material 24 and the sealing material 24 is appropriate for obtaining the sealing characteristics is determined by sandwiching the solid polymer electrolyte membrane 6 and the sealing material 24 with the bipolar electrode 7 and pressing with a predetermined pressure. It can be confirmed by measuring the electrical resistance at that time.
[0048]
  If it is determined as inappropriate by this measurement, the combination of the solid polymer electrolyte membrane 6 and the sealing material 24 is changed, or a sealing material 24 having a different thickness is prepared, and an appropriate thickness is prepared from them. Combinations with good electrical resistance value by selecting and usingTheYou can choose.
  Further, the sealing material is preferably provided in a ring shape around the through-hole 8 that forms the pure water supply path B, whereby the sealing performance with the pure water supply path B is improved.
[0049]
  Furthermore, the solid polymer electrolyte membrane 6 and the sheet-like sealing material 24 are crushed by the weight of the bipolar electrode 7.RuIn order to prevent this, it is desirable to use a water electrolysis cell in which the number of stacked bipolar electrodes 7 is limited, and to arrange a plurality of them in a multistage state.
[0050]
  The cathode main electrode 4 can be brought into contact with the mounting table 17 in the same manner as the hydrogen high-pressure vessel 2 so that the anode main electrode 5 is insulated from the high-pressure vessel 2, and the high-pressure vessel 2 is grounded (not shown). When connected, the cathode main electrode 4 becomes ground potential, the anode main electrode 5 becomes insulated from the ground potential, and when a power source is connected between the current introduction terminal 27 and ground, power is supplied to the water electrolysis cell 3.
[0051]
  When electric power necessary for electrolysis of water is supplied from the current introduction terminal 27 to the anode main electrode 5 through the lead wire 32 and pure water is supplied from the pure water supply pipe 47, it is provided on the anode in contact with the pure water supply path B. Pure water is supplied to the porous power supply 11 from each of the pure water supply ports 8a, and oxygen generated by electrolysis of pure water and pure water that has not been electrolyzed pass through a plurality of permeation through the discharge ports 12. Collected in the oxygen discharge passage A composed of the holes 9, 9..., Returns to an oxygen storage high-pressure vessel (not shown) (not shown) through the oxygen discharge pipe 42.
[0052]
  Further, hydrogen and permeated pure water generated at the cathode are directly discharged into the high-pressure vessel 2 from the discharge port 10, and the permeated pure water is discharged from the pure water discharge pipe 48 and collected in a drain tank (not shown). Hydrogen stored in the high-pressure vessel 2 is taken out from a hydrogen supply port 38 formed in the high-pressure vessel 2.
[0053]
  When the oxygen pressure in the oxygen storage high-pressure vessel (not shown) and the hydrogen pressure in the high-pressure vessel 2 are controlled to be the same pressure, the differential pressure acting on both ends of the solid polymer electrolyte membrane 6 and the solid polymer The differential pressure acting on the seal portion 24 between the bipolar electrodes 7 sealed by the electrolyte membrane 6 can be reduced to 0. During normal operation, the differential pressure between hydrogen and oxygen is within the breakdown voltage of the water electrolysis cell 3. By controlling, even if the pressure of hydrogen stored in the high-pressure vessel 2 becomes higher than the cell pressure resistance, the solid polymer electrolyte membrane 6 is damaged or oxygen leaks from the seal portion 24 into the high-pressure vessel 2. There is nothing to do.
[0054]
  FIG. 2 is an exploded perspective view of the water electrolysis cell 3 shown in FIG. 1. The water electrolysis cell 3 includes a ring-shaped solid polymer electrolyte membrane 6 between the cathode main electrode 4 and the anode main electrode 5. And a plurality of sheet-like sealing materials 24 formed in a ring shape provided on the outer periphery thereof and a plurality of ring-shaped bipolar electrodes 7 having the same diameter and stacked in the vertical direction. The discharge port 12 for discharging the generated oxygen and pure water that has not been electrolyzed to the outside of the high-pressure vessel 2 is provided on the anode side of each member, and the generated hydrogen permeates on the cathode side. Discharge holes 10 for directly discharging pure water into the high-pressure vessel 2 are formed.
[0055]
  Except for the anode main electrode 5, a through-hole 8 that forms a pure water supply path B for supplying pure water for electrolysis is provided in the center of each member. Has a pure water supply port 8a for supplying pure water to the anode, and the anode main electrode 5 has a sealing portion 5a for sealing the end of the pure water supply path B, a hole, and a pure water connected to the hole. A water supply port 8a and a discharge port 12 for oxygen or the like are provided.
[0056]
  Further, on the side wall of each bipolar electrode 7, there is provided a discharge port 10 for hydrogen or the like communicating with the cathode for discharging hydrogen generated at the cathode and permeated pure water into the high-pressure vessel 2. .
[0057]
  Therefore, as is apparent from FIG. 2, the pure water supplied from the pure water supply path B formed at the center of the cathode main electrode 4 is distributed from the pure water supply port 8a to the porous porous power supply 11 of the anode. The oxygen generated at the anode and the undecomposed pure water flow into the oxygen discharge path A from the discharge port 12 for oxygen and the like, are taken out of the high-pressure vessel 2 through the oxygen discharge pipe 42, and are generated at the cathode. The permeated pure water is discharged directly into the high-pressure vessel 2 from the discharge port 10 for hydrogen or the like.
[0058]
  The porous power supply 11 is made of titanium mesh or the like, and is in contact with the solid polymer electrolyte membrane 6 in which the end surface is fixed to the inner wall surface of the bipolar electrode 7 by welding and the platinum catalyst is formed on both surfaces. The surface to be polished is polished and finished smooth, and a carbon film formed by an ECR plasma deposition method is applied to the surface.
[0059]
  In FIG. 2, each member constituting the water electrolysis cell 3 is provided with a positioning groove 22 along the axial direction on the outer peripheral portion in order to facilitate assembly.
[0060]
  FIG. 3 is an explanatory view showing the state of the flow of pure water supplied to the anode. In the figure, the arrow indicates the flow of pure water, and the pure water is supplied from the pure water supply path B provided in the center. It is supplied to the port 8a, flows toward the inner peripheral wall of the bipolar electrode 7 with a 360 ° spread, passes through a discharge port 12 of oxygen or the like that is formed in a tapered shape, and passes through the through hole 9a. Into the oxygen discharge path A formed by
[0061]
【The invention's effect】
  The high-pressure hydrogen production apparatus according to the present invention is a multipolar, multi-layered type in which a solid polymer electrolyte membrane having a catalyst layer formed on both sides and a plurality of bipolar electrodes made of a porous power supply in contact with both sides are laminated. Since the water electrolysis cell was configured, the lower part of the water electrolysis cell was provided on a mounting table provided in the high pressure vessel, and the upper part was held in a pressed state by a holding jig arranged in the high pressure vessel. And the diameter of the high-pressure vessel itself can be further reduced.
[0062]
  In particular, in a high-pressure vessel in which the wall thickness must be increased in proportion to the square of the diameter of the vessel itself, the cell diameter can be reduced to 1 / 1.5 to 1 / Since the diameter of the high-pressure vessel can be reduced accordingly, the wall thickness can be reduced to ½ to ¼ compared with the conventional case.
[0063]
  In addition, even if the cell diameter is reduced, it does not reduce the area of the portion of the solid polymer electrolyte membrane that contributes to water electrolysis, which is the effective capacity of the water electrolysis cell. In other words, the water electrolysis efficiency is remarkably improved.
[0064]
  Furthermore, in the present invention, the use of a pressing member having a pressing force facilitates uniform tightening of the water electrolysis cell, and as a result, the cell breakdown voltage can be increased.
[0065]
  In other words, in the present invention, water electrolysis is performed using the presser member.Top edge of cellIs pressed downward, the force point for tightening the water electrolysis cell moves to the center of the water electrolysis cell, the water electrolysis cell can be tightened more uniformly, and there is no leakage from the seal portion.
[0066]
  Further, according to the present invention, pure water is supplied from a pure water supply path provided in the center of the water electrolysis cell, and the generated oxygen and undecomposed pure water are taken up and down on the anode side inside the bipolar electrode. Since it is performed through an oxygen discharge path provided in communication with the direction, a uniform pure water flow from the center to the outer periphery of the water electrolysis cell can be formed, and local heating of the PEM is prevented, and the PEM is locally softened. It is possible to prevent the breakdown voltage from being lowered.
[0067]
  In the present invention, hydrogen and permeated pure water generated at the cathode are directly discharged into the high-pressure vessel from the discharge port of hydrogen or the like formed on the outer peripheral portion on the cathode side of the bipolar electrode. There is also an effect that can be made smaller.
[0068]
  Further, in the present invention, the porous power feeder is fixed in the bipolar electrode by welding or the like and the surface thereof is polished, so that the PEM is uniformly tightened and is not damaged by protrusions or steps, and the pressure resistance The cause of lowering the pressure resistance such as lowering the pressure or obstructing the sealing characteristics is eliminated.
[0069]
  By adopting the above-described novel water electrolysis cell structure, the present invention can eliminate the deterioration factor of the pressure resistance of the water electrolysis cell, stably generate high-pressure hydrogen, improve safety, and In addition, there are many effects in terms of performance and economy, such as the diameter of the high-pressure vessel accommodating the water electrolysis cell can be reduced and the vessel wall thickness can be reduced.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view showing an example of a high-pressure hydrogen production apparatus according to the present invention.
FIG. 2 is an exploded perspective view of the water electrolysis cell in FIG.
FIG. 3 is an explanatory diagram showing a pure water flow at the anode of the water electrolysis cell of the present invention.
[Explanation of symbols]
    1 High-pressure hydrogen production system
    2 High pressure vessel
    3 Multi-layer, water electrolysis cell
    4 Cathode main electrode
    5 Anode main electrode
    6 Solid polymer electrolyte membrane
    7 Bipolar electrode
    A oxygen discharge path
    B Pure water supply channel
  10 Hydrogen outlet
  11 Porous feeder
  12 Oxygen outlet
  16 Separation wall
  17 Mounting table
  19 Spring body
  23 Presser jig
  24 Sheet-like sealing material

Claims (14)

A solid polymer electrolyte membrane with the catalyst layer formed on both sides, by laminating a plurality of the bipolar electrodes formed of a porous current collector in contact with both sides, constitute a stacked-type water electrolysis cell a double-pole type,
The water electrolysis cell, Rutotomoni provided on a mounting table provided in a high-pressure vessel, from the top of the water electrolysis cell and sandwiched by the pressing jig is one end to the inner wall of the high pressure vessel is fixed maintained, more An apparatus for producing high-pressure hydrogen, characterized in that the bipolar electrode is held in a pressed state. A multi-layered water electrolysis cell is constructed by laminating a plurality of multi-polar electrodes composed of a solid polymer electrolyte membrane having a catalyst layer formed on both surfaces and a porous power supply in contact with both surfaces,
The water electrolysis cell is held in the high-pressure vessel in a compressed state using a holding jig whose one end is fixed and maintained on the inner wall of the high-pressure vessel,
A high-pressure hydrogen production apparatus characterized in that a pure water supply path is formed at the center of each bipolar electrode. A multi-layered water electrolysis cell is constructed by laminating a plurality of multi-polar electrodes composed of a solid polymer electrolyte membrane having a catalyst layer formed on both surfaces and a porous power supply in contact with both surfaces,
The water electrolysis cell is held in the high pressure vessel in a compressed state by using a holding jig whose one end is fixed and maintained on the inner wall of the high pressure vessel.
The provided pure water supply path to the center of each double-pole electrode, the anode side of the double-polar electrode oxygen and pure water outlet, respectively,
An oxygen discharge path is formed in the vertical direction on the outer periphery of each bipolar electrode so as to be in contact with the oxygen and pure water discharge ports,
An apparatus for producing high-pressure hydrogen, wherein a discharge port for directly discharging hydrogen and pure water to a high-pressure vessel is provided on the cathode side. The bipolar electrode is:
The high-pressure hydrogen production apparatus according to any one of claims 1 to 3, wherein the shape is a disk shape. The solid polymer electrolyte membrane is:
The high-pressure hydrogen production apparatus according to any one of claims 1 to 4, wherein the high-pressure hydrogen production apparatus is fixed to the bipolar electrode in a state where a sheet-like sealing material is provided on an outer periphery thereof. The sealing material is
6. The high-pressure hydrogen production apparatus according to claim 5, wherein the high-pressure hydrogen production apparatus is made of a material thinner than the solid polymer electrolyte membrane and harder than the electrolyte membrane. The water electrolysis cell in the pressed state is
The high-pressure hydrogen production apparatus according to any one of claims 1 to 3, wherein the plurality of bipolar electrodes are arranged in a multistage state. The mounting table for the water electrolysis cell is:
The high-pressure hydrogen production apparatus according to claim 1, further comprising a pure water supply port that supplies pure water to the pure water supply path. The holding jig is
It is composed of a jig main body fixed to the upper part of the water electrolysis cell, a spring body mounted in the jig, and a presser screw for biasing the spring body and having one end held in the high-pressure vessel. The high-pressure hydrogen production apparatus according to any one of claims 1 to 3, wherein The bipolar electrode is:
The high-pressure hydrogen production apparatus according to any one of claims 1 to 3, wherein the apparatus is stacked in the vertical direction, the upper surface being an anode and the lower surface being a cathode. The porous feeder is
The high pressure hydrogen production apparatus according to any one of claims 1 to 3, wherein the high pressure hydrogen production apparatus is fixed inside the water electrolysis cell by welding. The water electrolysis cell is
The high-pressure hydrogen production apparatus according to any one of claims 1 to 3, wherein the surface of the porous power feeder in contact with the solid polymer electrolyte membrane is polished. The water electrolysis cell is
The high-pressure hydrogen production apparatus according to any one of claims 1 to 3, wherein the surface of the porous power supply body in contact with the solid polymer electrolyte membrane is polished and the surface is coated with a carbon film. The carbon film is
The high pressure hydrogen production apparatus according to claim 13 , wherein the high pressure hydrogen production apparatus is formed by an ECR plasma deposition method.

Images