JP2006063419A - Hydrogen production apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hydrogen production apparatus where, even if the pressure on a cathode is made high, the deformation of an anode feed body can be prevented. <P>SOLUTION: This hydrogen production apparatus is equipped with feed bodies 3, 4 provided on both the sides of a solid high molecular membrane 2 and separators 5, 6. The separator 6 on the anode side is composed of a material capable of retaining its shape against the pressure of gaseous hydrogen, and includes fluid passage regions 19b and frame regions 20b. The anode feed body 4 is composed of a porous member 16 confronted with the fluid passage region 19b and nonporous members 17 confronted with the frame regions 20b. The anode feed body 4 comprises the porous member 16 obtained by sintering titanium powder and the nonporous members 17 composed of titanium, and the boundary between the porous member 16 and each nonporous member 17 is smoothly joined. The porous member 16 and each nonporous member 17 are joined by press-fitting, electron beam welding or diffusion joining. The cathode feed body 3 is composed of only a porous member confronted with fluid passage regions 19a in the separator 5 on the cathode side. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a hydrogen production apparatus.

  Conventionally, as shown in FIG. 4, a solid polymer film 2, a cathode power supply 22, an anode power supply 23 provided opposite to each other on both sides thereof, and separators 5 stacked on the respective power supplies 22 and 23. 6 is known (see, for example, Patent Document 1).

  In the high-pressure hydrogen production apparatus 21, for example, the separators 5 and 6 are provided with fluid passages 7 and 8 in which the power feeders 22 and 23 are exposed, and water is supplied to the fluid passage 8 of the anode-side separator 6 and the cathode-side separator 5. Hydrogen gas is extracted from the fluid passage 7. The power feeding bodies 22 and 23 are energized through separators 5 and 6, respectively. Moreover, each electric power feeding body 22 and 23 consists of a porous member, and fluid can be distribute | circulated freely. As such a porous member, for example, a member obtained by sintering conductive particles such as titanium powder is known (see, for example, Patent Document 2).

  According to the high-pressure hydrogen production device 21, when water is supplied to the fluid passage 8 of the anode separator 6 and the cathode power supply 22 and the anode power supply 23 are energized, the water supplied to the fluid passage 8 becomes the anode power supply. Electrolysis is performed at 23 to generate hydrogen ions and oxygen gas. The hydrogen ions permeate the solid polymer film 2 and move to the cathode power supply 22 side, receive electrons from the cathode power supply 22 and become hydrogen gas.

  As a result, in the high-pressure hydrogen production device 21, high-pressure hydrogen can be obtained in the fluid passage 7 of the cathode-side separator 5. On the other hand, oxygen generated in the fluid passage 8 of the anode-side separator 6 is discharged from a drain port 15 provided in the fluid passage 8 together with the water.

  However, in the high-pressure hydrogen production apparatus 21, when oxygen is discharged as described above, the pressure balance between the cathode side and the anode side is lost, and the solid polymer is generated by the pressure of hydrogen generated in the fluid passage 7 of the cathode side separator 5. There is a disadvantage that the membrane 2 and the anode power supply 23 are pressed in the direction of the separator 6.

  Here, the anode power supply body 23 is made of the porous member, and when pressed as described above, the anode power supply body 23 is compressed in the thickness direction to reduce the thickness, while being spread in a direction orthogonal to the thickness. As a result, the edge of the anode power supply body 23 made of the porous member may move relative to the solid polymer film 2 to damage the solid polymer film 2.

Further, when the thickness of the anode power supply 23 is reduced, the solid polymer film 2 is compressed and deformed toward the anode power supply 23, and a gap is generated between the solid polymer film 2 and the cathode power supply 22. When the gap is generated, the contact resistance between the solid polymer film 2 and the cathode power supply 22 is increased, and the performance of the high-pressure hydrogen production apparatus 21 is deteriorated.
Special table 2003-523599 gazette JP 2004-71456 A

  An object of the present invention is to provide a hydrogen production apparatus that can eliminate such inconveniences and prevent deformation of the anode power feeder when the cathode side becomes high pressure.

  In order to achieve such an object, the present invention provides a solid polymer film, a pair of power feeding bodies provided opposite to both the cathode side and the anode side of the solid polymer film, and a laminate on each power feeding body. Each of the separators and a fluid passage provided in each separator and exposing each power supply body. Water is supplied to the fluid passage of the anode separator and energized to each power supply body, whereby the fluid passage of the anode separator is provided. In a hydrogen production apparatus that electrolyzes the supplied water and obtains high-pressure hydrogen gas in the fluid passage of the cathode-side separator, the anode-side separator resists the pressure of the hydrogen gas obtained in the fluid passage of the cathode-side separator. An anode power supply comprising a fluid passage region in which the fluid passage is provided and a frame region provided on the outer peripheral side of the fluid passage region. Is disposed in close contact with the solid polymer membrane and the anode-side separator, and a porous member that sinters conductive particles and occupies a region facing the fluid passage region; and It is characterized by comprising a non-porous member that occupies opposing regions, surrounds the porous member, and regulates deformation in a direction orthogonal to the thickness of the porous member.

  In the hydrogen production apparatus according to the present invention, the anode power feeder is constituted by the porous member and the non-porous member, and the porous member faces the fluid passage region. Therefore, the pressure of the hydrogen gas obtained in the fluid passage of the cathode separator acts on the porous member and presses the porous member toward the anode separator.

  However, in the hydrogen production apparatus of the present invention, the anode feeder is disposed in close contact with the solid polymer membrane and the anode separator, and the anode separator resists the pressure of the hydrogen gas. It is made of a material that can maintain its shape. Further, the porous member of the anode power feeding body is surrounded by the non-porous member. Therefore, when the porous member is pressed in the direction of the anode side separator by the pressure of the hydrogen gas, the deformation is regulated by the anode side separator itself in contact with the anode side separator in the thickness direction. In a direction orthogonal to the vertical direction, deformation is restricted by the non-porous member.

  As a result, according to the hydrogen production apparatus of the present invention, the edge of the anode power feeder does not move, and the solid polymer membrane can be prevented from being damaged by the edge. Further, according to the hydrogen production apparatus of the present invention, since the thickness of the anode feeder is not reduced, there is no gap between the solid polymer film and the cathode feeder, Can be prevented from increasing.

  Examples of the anode feeder include those made of the porous member obtained by sintering titanium powder and the non-porous member made of titanium. The non-porous member is made of titanium. A board material etc. can be mentioned. In order to prevent damage to the solid polymer film when the solid polymer film is pressed against the anode power supply by the pressure of the hydrogen gas, the anode power supply includes the porous member and the non-porous material. It is preferable to join so that the boundary with the material member becomes smooth.

  In the anode power feeder, the porous member formed by sintering titanium particles and the non-porous member formed of titanium are joined by one method selected from the group consisting of press-fitting, electron beam welding, and diffusion joining. It is preferable that The porous member and the non-porous member can be easily joined by any of the above methods, and the boundary between the two can be smoothed without any step.

  Since the pressure of the hydrogen gas does not act on the cathode power supply body, it is not necessary to provide the non-porous member to prevent deformation, and faces the fluid passage region where the fluid passage of the cathode separator is provided. It can comprise only the porous member which occupies an area | region. The cathode power supply body can be manufactured at low cost by being composed of only the porous member. Examples of the porous member include those obtained by sintering titanium powder, as in the case of the anode-side power feeder.

  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 plan view showing the configuration of the anode power supply used in the high-pressure hydrogen production apparatus of FIG. 1, and FIG. 1 is a main part assembly diagram of the high-pressure hydrogen production apparatus shown in FIG.

  As shown in FIG. 1, the high-pressure hydrogen production apparatus 1 of the present embodiment includes a solid polymer film 2, a cathode power supply 3, an anode power supply 4 provided opposite to each other, and each power supply 3. , 4 and fluid passages 7 and 8 provided in the separators 5 and 6 and exposing the power feeding members 3 and 4, respectively.

  The solid polymer film 2, the power feeders 3 and 4, and the separators 5 and 6 are sandwiched between end plates 10 and 10 via insulating members 9 and 9 stacked on the separators 5 and 6. , 10 are pressed by the bolts 11 and the nuts 12 attached to each other and are brought into close contact with each other. The cathode side separator 5 includes a hydrogen outlet 13 that communicates with the fluid passage 7, and the anode side separator 6 includes a water supply port 14 and a drain port 15 that communicate with the fluid passage 8. The power feeders 3 and 4 are energized through the separators 5 and 6, respectively.

In the high-pressure hydrogen production apparatus 1, the solid polymer membrane 2 is a cation permeable membrane, and for example, Nafion (manufactured by DuPont), Asplex (manufactured by Asahi Kasei Co., Ltd.) or the like can be used. The solid polymer membrane 2 includes a catalyst layer (not shown) containing, for example, a platinum catalyst on the anode side, and a catalyst layer (not shown) containing, for example, a RuIrFeO _X catalyst on the cathode side.

  As shown in FIG. 2, the anode power feeder 4 includes a porous titanium sintered body 16 and a titanium plate 17 surrounding the porous titanium sintered body 16. The porous titanium sintered body 16 can be obtained, for example, by filling a sintered container having a predetermined shape with a spherical gas atomized titanium powder produced by a gas atomizing method for solidifying molten splashes of titanium during scattering and vacuum sintering. Can be used. The titanium plate 17 is substantially non-porous.

As shown in FIG. 2A, the anode power supply 4 is formed by press-fitting a porous titanium sintered body 16a formed in a disk shape into an inner peripheral portion of a titanium plate 17a formed in a donut shape. can do. Further, as shown in FIG. 2 (b), the anode power feeding body 4 has titanium plates 17b ₁ , b ₂ , b ₃ , and b ₄ arranged around the porous titanium sintered body 16b formed in a rectangular shape. It may be formed by beam welding. In this case, the titanium plates 17b ₁ and b ₂ , the titanium plates b ₂ and b ₃ , the titanium plates b ₃ and b ₄ , and the titanium plates b ₄ and b 1 are welded and joined from the back side by the welded portions 18a. Further, the porous titanium sintered body 16b is welded and joined from the back surface side to the titanium plates 17b ₁ , b ₂ , b ₃ , and b ₄ by the welded portions 18b around the four circumferences. In the configuration shown in FIG. 2B, diffusion bonding may be used instead of electron beam welding.

  The anode feeder 4 is obtained by integrating the porous titanium sintered body 16 and the titanium plate 17 as described above, and then performing slicing processing, surface grinding, etc. on the surface in contact with the solid polymer film 2. The boundary between the porous titanium sintered body 16 and the titanium plate 17 can be easily made smooth without a step. As a result, it is possible to prevent the solid polymer film 2 from being damaged by being pressed by the boundary between the porous titanium sintered body 16 and the titanium plate 17.

  The cathode power supply 3 is obtained in exactly the same manner as the porous titanium sintered body 16 and has the same shape as the porous titanium sintered body 16. Since the cathode power supply 3 does not receive the pressure of the hydrogen gas generated in the fluid passage 7 of the cathode-side separator 5, the cathode power supply 3 does not need to be provided with the titanium plate 17 around it, and is less expensive because the titanium plate 17 is not provided. Can be manufactured.

  As the separators 5 and 6, for example, non-porous titanium material or the like formed with fluid passages 7 and 8 can be used. Here, as shown in FIG. 3, the cathode separator 5 includes a fluid passage region 19a in which the fluid passage 7 is provided and a frame region 20a provided on the outer peripheral side of the fluid passage region 19a. And the cathode electric power feeder 3 is arrange | positioned so that the area | region which opposes the fluid channel | path area | region 19a may be occupied.

  As shown in FIG. 3, the anode-side separator 6 includes a fluid passage region 19b in which the fluid passage 8 is provided, and a frame region 20b provided on the outer peripheral side of the fluid passage region 19b. The anode power supply 4 is disposed so that the porous titanium sintered body 16 occupies a region facing the fluid passage region 19b and the titanium plate 17 occupies a region facing the frame region 20b.

  In the high-pressure hydrogen production apparatus 1 having the above-described configuration, when water is supplied from the water supply port 14 to the fluid passage 8 and the cathode power supply 3 and the anode power supply 4 are energized through the separators 5 and 6, the water is electrolyzed. As a result, hydrogen ions, electrons, and oxygen gas are generated in the fluid passage 8. Next, the hydrogen ions permeate the solid polymer membrane 2 which is a cation permeable membrane with some water molecules due to the potential difference between the cathode power supply 3 and the anode power supply 4, and the cathode power supply 3 side. Move to. Then, the hydrogen ions receive electrons from the cathode power supply 3 and are molecularized, whereby high-pressure hydrogen gas is obtained in the fluid passage 7.

  On the other hand, the oxygen gas generated in the fluid passage 8 is discharged from the drain port 15 together with most of the water. However, in this way, the balance of pressure is lost between the cathode side and the anode side. As a result, the solid polymer membrane 2 and the porous titanium sintered body 16 of the anode power feeder 4 are pressed in the direction of the anode separator 6 by the high-pressure hydrogen gas obtained in the fluid passage 7 of the cathode separator 5. It will be.

  At this time, in the high-pressure hydrogen production apparatus 1, the anode separator 6 is made of a non-porous titanium material or the like as described above, and has a sufficient thickness because the fluid passage 8 is formed. Rigidity capable of maintaining the shape without being deformed against the pressure. The anode power supply 4 is disposed in close contact with the anode separator 6. In addition, the anode power supply 4 has a configuration in which the porous titanium sintered body 16 is surrounded by a titanium plate 17. As a result, the deformation of the porous titanium sintered body 16 of the anode power supply body 4 is restricted by the anode separator 6 in the thickness direction, and the deformation is restricted by the titanium plate 17 in the direction orthogonal to the thickness. There is nothing to do.

  As described above, since the porous titanium sintered body 16 does not deform in the direction orthogonal to the thickness, the end of the porous titanium sintered body 16 does not move relative to the solid polymer film 2. The solid polymer film 2 is not damaged by the end portion. In addition, since the porous titanium sintered body 16 is not deformed in the thickness direction, a gap is generated between the solid polymer film 2 and the cathode power supply 3 even when the solid polymer film 2 is pressed in the direction of the anode separator 6. Nor. Therefore, an increase in contact resistance between the solid polymer film 2 and the cathode power supply 3 can be prevented.

  Next, examples of the present invention and comparative examples will be described.

  In this example, first, a spherical gas atomized titanium powder produced by a gas atomizing method that solidifies molten droplets of titanium during scattering is filled into a predetermined shaped sintering vessel and vacuum sintered, and then the surface is ground. The porous titanium sintered body 16a shown in FIG. 2 (a) was manufactured by processing into an outer diameter of 28 mm, a fitting tolerance h6, and a thickness of 1 mm. Next, a plate corresponding to two types of pure titanium is processed into an outer diameter of 56 mm, an inner diameter of 28 mm, a fitting tolerance H6, and a thickness of 1 mm to produce a donut-shaped titanium plate 17a shown in FIG. The porous titanium sintered body 16a was press-fitted into the inner peripheral portion of the inner peripheral portion and integrated to produce the anode power feeding body 4.

  Next, the cathode power supply body 3 exactly the same as the porous titanium sintered body 16a was manufactured.

  Next, as shown in FIG. 3, the cathode power supply 3 and the anode power supply 4 are disposed on both sides of a 100 μm thick solid polymer film 2 carrying a catalyst on both electrodes of the film (not shown). Furthermore, separators 5 and 6 made of a titanium material were stacked on the cathode power supply 3 and the anode power supply 4 to form the high-pressure hydrogen production apparatus 1. Next, the high pressure hydrogen production apparatus 1 in which the insulating members 9 and 9 are stacked on the separators 5 and 6 is further sandwiched between the end plates 10 and 10, and the bolts 11 and nuts 12 attached to the end plates 10 and 10 The structure shown in FIG. 1 was obtained.

  Next, hydrogen gas is produced by the high-pressure hydrogen production apparatus 1 having the above-described configuration, and the solid polymer film 2 and the porous titanium sintered body 16a are pressurized from the cathode side with the hydrogen gas at 40 MPa. The membrane 2 was not damaged, and the cathode side could be stably maintained at a pressure of 40 MPa. At this time, the hydrogen permeation amount of the solid polymer membrane 2 was approximately 1 ml / min or less.

Next, the same anode power supply 4 as that used in this example was mechanically pressurized at a pressure of 40 MPa for 3 minutes. After releasing the pressure, the amount of decrease in the thickness of the anode power supply 4 was measured and found to be 1 μm, and no substantial decrease was observed.
[Comparative Example 1]
In this comparative example 1, a high-pressure hydrogen production apparatus was produced in exactly the same manner as in example 1 except that the anode feeder 4 was constituted only by the porous titanium sintered body 16a.

  Next, when hydrogen gas was produced by the high-pressure hydrogen production apparatus of this comparative example, when the pressure on the solid polymer membrane 2 and the porous titanium sintered body 16a from the cathode side reached about 22 MPa, the solid polymer was produced. The membrane 2 was damaged and the cathode side could not be maintained at a high pressure.

  Next, when the same anode feeder 4 (porous titanium sintered body 16a) as that used in this comparative example was mechanically pressed at a pressure of 40 MPa for 3 minutes, the occurrence of plastic deformation was observed from about 20 MPa. It was. After releasing the pressure, the amount of decrease in the thickness of the anode power supply 4 was measured and found to be 50 μm, and a decrease of about 5% was observed.

  In this example, first, a spherical gas atomized titanium powder produced by a gas atomizing method that solidifies molten droplets of titanium during scattering is filled into a predetermined shaped sintering vessel and vacuum sintered, and then the surface is ground. The porous titanium sintered body 16a shown in FIG. 2 (a) was manufactured by processing into an outer diameter of 28 mm, a fitting tolerance h6, and a thickness of 300 mm. Next, a bulk material corresponding to two types of pure titanium is processed into an outer diameter of 56 mm, an inner diameter of 28 mm, a fit tolerance of H6, and a thickness of 300 mm to produce a donut-shaped titanium member 17a shown in FIG. The porous titanium sintered body 16a was press-fitted into the inner peripheral portion of 17a and integrated. Next, the anode power supply 4 was manufactured by slicing a member obtained by press-fitting the porous titanium sintered body 16a into the inner peripheral portion of the titanium member 17a into a thickness of 1 mm and then grinding the surface.

  Next, a high-pressure hydrogen production apparatus 1 was produced in exactly the same manner as in Example 1 except that the anode feeder 4 obtained in this example was used.

  Next, hydrogen gas was produced in exactly the same manner as in Example 1 except that the high-pressure hydrogen production apparatus 1 of this example was used, and the solid polymer membrane 2 and porous titanium sintered from the cathode side with the hydrogen gas. The body 16a was pressurized at 40 MPa. At this time, the hydrogen permeation amount of the solid polymer membrane 2 was approximately 1 ml / min or less.

  According to the method of the present embodiment, the anode power supply 4 having a structure in which the porous titanium sintered body 16a is press-fitted into the inner peripheral portion of the titanium plate 17a and integrated can be easily manufactured in large quantities.

In this example, first, a spherical gas atomized titanium powder produced by a gas atomizing method that solidifies molten droplets of titanium during scattering is filled into a predetermined shaped sintering vessel and vacuum sintered, and then the surface is ground. The porous titanium sintered body 16b shown in FIG. 2 (b) was manufactured by processing into a 30 mm square and a thickness of 1 mm. Next, a plate corresponding to two types of pure titanium is processed into a length of 40 mm, a width of 10 mm, and a thickness of 1 mm to produce titanium plates 17b ₁ , b ₂ , b ₃ , and b ₄ shown in FIG. Anode feeder 4 was manufactured by electron beam welding of titanium plates 17b ₁ , b ₂ , b ₃ , and b ₄ around porous titanium sintered body 16b. At this time, the weld bead width was 1.5 mm, and the weld depth was 0.6 to 0.8 mm.

  Next, a high-pressure hydrogen production apparatus 1 was produced in exactly the same manner as in Example 1 except that the anode feeder 4 obtained in this example was used.

  Next, hydrogen gas was produced in exactly the same manner as in Example 1 except that the high-pressure hydrogen production apparatus 1 of this example was used, and the solid polymer membrane 2 and porous titanium sintered from the cathode side with the hydrogen gas. The body 16a was pressurized at 40 MPa. At this time, the hydrogen permeation amount of the solid polymer membrane 2 was approximately 1 ml / min or less.

According to the method of the present embodiment, the odd-shaped anode power feeder 4 having a configuration in which the titanium plates 17b ₁ , b ₂ , b ₃ , and b ₄ are joined and integrated around the porous titanium sintered body 16b, It can be manufactured easily.

Explanatory sectional drawing which shows the structure of the hydrogen production apparatus of this invention. The top view which shows the structure of the anode electric power feeding body used for the hydrogen production apparatus of FIG. The principal part assembly drawing of the hydrogen production apparatus shown in FIG. Explanatory sectional drawing which shows the structure of the conventional hydrogen production apparatus.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Hydrogen production apparatus, 2 ... Solid polymer membrane, 3 ... Cathode electric power supply, 4 ... Anode electric power supply, 5 ... Cathode side separator, 6 ... Anode side separator, 7, 8 ... Fluid passage, 16 ... Porous member, 17 ... Non-porous member, 19a, 19b ... Fluid passage region, 20a, 20b ... Frame region.

Claims (4)

A solid polymer film, a pair of power supply bodies provided opposite to each other on both the cathode side and the anode side of the solid polymer film, a separator stacked on each power supply body, and each power supply provided on each separator A fluid passage exposing the body, and supplying water to the fluid passage of the anode-side separator and energizing each power feeding body to electrolyze the water supplied to the fluid passage of the anode-side separator, In a hydrogen production apparatus for obtaining high-pressure hydrogen gas in the fluid passage of
The anode separator is made of a material capable of maintaining a shape against the pressure of hydrogen gas obtained in the fluid passage of the cathode separator, and includes a fluid passage region in which the fluid passage is provided, and an outer periphery of the fluid passage region. Frame area provided on the side,
The anode power supply is disposed in close contact with the solid polymer membrane and the anode-side separator, and a porous member occupying a region facing the fluid passage region formed by sintering conductive particles; A hydrogen production apparatus comprising: a non-porous member that occupies a region facing a frame region, surrounds the porous member, and restricts deformation in a direction orthogonal to the thickness of the porous member.   The anode feeder is composed of the porous member obtained by sintering titanium powder and the non-porous member made of titanium, so that the boundary between the porous member and the non-porous member becomes smooth. The hydrogen production apparatus according to claim 1, wherein the hydrogen production apparatus is joined.   In the anode power supply body, the porous member formed by sintering titanium powder and the non-porous member formed of titanium are bonded by one method selected from the group consisting of press-fitting, electron beam welding, and diffusion bonding. The hydrogen production apparatus according to claim 2, wherein   The said cathode electric power feeding body consists only of the porous member which occupies the area | region which opposes the fluid passage area | region where the fluid passage of the cathode side separator is provided, The Claim 1 thru | or 3 characterized by the above-mentioned. Hydrogen production equipment.

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