JP2006131944A - Vessel enclosed type water electrolyzer in water electrolysis-hydrogen generator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a high pressure vessel enclosed type water electrolysis-hydrogen generator in which constitution is simple and assembling is facilitated, and which can generate a large quantity of hydrogen. <P>SOLUTION: Water electrolyzers 24, 24' are fixed to the insides of left and right vessels 21, 21' in which one end has bottom walls 22, 22' and the other end is opened at the vessel bottom walls, and the vessels are opposed and coupled, so as to form a pressure vessel 28. The left and right water electrolyzers 24, 24' in the pressure vessel 28 are connected to another power sources 30, 30'. The anode of the power sources 30, 30' is connected to the anode of the water electrolyzers 24, 24' via pressure terminals 31, 31' provided at the upper walls of the vessels 21, 21', and the cathode of the power sources 30, 30' is connected to the cathode of the water electrolyzers 24, 24' via the vessels 21, 21'. Pure water is fed from water feed ports provided at both the edge walls of the pressure vessel 28 into the pressure vessel 28, and is stored in the vessel. Oxygen generated at the anodes is discharged from oxygen discharge ports provided at both the edge walls in the pressure vessel 28, and hydrogen generated at the cathodes is discharged from the upper gas outlet 32 provided at the upper part of the pressure vessel 28. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a high-pressure hydrogen production apparatus that generates a high-pressure hydrogen gas by electrolysis of water using a solid polymer electrolyte membrane, and more specifically, several tens of MPa, for example, a fuel cell vehicle travels the same distance as a gasoline vehicle. The present invention relates to a water electrolysis hydrogen generator capable of supplying high-pressure hydrogen gas of at least 40 MPa, preferably 80 MPa required at a hydrogen station, and more particularly to a container-encased water electrolysis tank.

  A polymer electrolyte membrane that electrolyzes water, generates oxygen at the anode and hydrogen at the cathode, and a hydrogen gas / liquid that separates water and hydrogen generated at the cathode of the water electrolysis tank Hydrogen having a separator, an oxygen gas-liquid separator that separates oxygen and water generated at the anode of the water electrolysis tank, and a water supply line having a water supply pump that supplies water from the pure water tank to the water electrolysis tank The supply device is conventionally known. The high pressure vessel-accommodating water electrolysis hydrogen generator is a device in which a hydrogen supply device having such a configuration is housed in a vessel capable of maintaining a predetermined high pressure.

  Conventionally, as shown in FIG. 6, a container-containing water electrolysis hydrogen generator is a solid polymer water electrolyzer that electrolyzes water using a polymer electrolyte membrane and generates oxygen at the anode and hydrogen at the cathode, respectively. (120), a pressure vessel (121) having a water inlet on the left side wall, a water / oxygen outlet on the right side wall, and containing the water electrolyzer (120), and hydrogen gas provided on the top wall of the pressure vessel Extraction device (122), hydrogen line (123) provided in hydrogen gas extraction device, oxygen line (124) connected to water / oxygen discharge port of pressure vessel, water electrolysis tank provided in oxygen line An oxygen gas-liquid separator (125) for separating oxygen and water generated at the anode of (120), a water circulation line (126) connecting the oxygen gas-liquid separator and the water inlet of the pressure vessel, and a water electrolyzer And a DC power source (not shown) connected to (120). The pressure vessel (121) is composed of a cylindrical member and cone-shaped end wall members provided at both ends thereof (see Patent Document 1).

  However, in the high pressure vessel-accommodating water electrolysis hydrogen generator configured as described above, a large ingot is required to produce a large-capacity pressure vessel from a metal ingot, but it is extremely difficult to obtain such an ingot. is there.

  Moreover, in the conventional container-accommodated water electrolysis hydrogen generator, the water electrolyzer is prevented from being damaged by preventing a differential pressure from being generated between the inside and outside of the water electrolyzer and between the anode and the cathode.

In this method, since only one water electrolysis tank can be installed in the pressure vessel, it is necessary to increase the number of unit cells stacked in one water electrolysis tank in order to generate a large amount of hydrogen. However, since the high-pressure vessel is formed by cutting an ingot, the number of unit cells stacked cannot be increased due to the limitation of the cutting depth, and the amount of hydrogen generated is limited. In addition, when the number of layers is large, it is difficult to manufacture.
Japanese Patent Laid-Open No. 204-2914, in particular, Example 1 and FIG.

  In view of the above circumstances, an object of the present invention is to provide a high pressure vessel-accommodating water electrolysis hydrogen generator that is simple in construction and easy to assemble and that can generate a large amount of hydrogen.

  The present invention has been devised to solve the above problems.

  According to the first aspect of the present invention, a water electrolyzer is disposed inside a pair of left and right containers each having a bottom wall at one end and the other end being opened, and fixed at the container bottom wall. A high pressure vessel-accommodating water electrolysis hydrogen generator is formed by combining the open ends together to form a pressure vessel.

  In the invention according to claim 2, the pair of left and right containers are electrically insulated, the water electrolyzers in each container are electrically connected in series, and the anode of the power source is connected to the water inside the container through one container. The high-pressure vessel-accommodating water electrolysis hydrogen generator according to claim 1, wherein the high-pressure vessel-accommodating water electrolysis hydrogen generator is connected to the anode of the electrolytic cell and the cathode of the power source is connected to the cathode of the water electrolyzer inside the other vessel.

  According to a third aspect of the present invention, the pressure vessel is provided with an oxygen outlet through which the anode side outlet of the water electrolyzer in each vessel communicates with the inside of the pressure vessel, and oxygen extracted from each anode is extracted. It is a high-pressure container accommodation type water electrolysis hydrogen generator of statement.

  According to a fourth aspect of the present invention, the pressure vessel is provided with a hydrogen outlet through which the cathode side outlet of the water electrolyzer in each vessel communicates with the inside of the pressure vessel and extracts hydrogen generated at each cathode. It is a high-pressure container accommodation type water electrolysis hydrogen generator of statement.

  According to a fifth aspect of the present invention, a water electrolysis tank is fixed to the inner surfaces of the bottom walls of a pair of containers having a bottom wall at one end and the other end open, and the other end side electrodes of these water electrolysis tanks are connected to the container. In a water electrolysis hydrogen generator, connected to a pressure terminal provided on a wall or connected to electrodes on the other end side, and then coupled so that a pair of containers face each other open ends and a water electrolyzer is contained inside This is a method of assembling a container-accommodating water electrolyzer.

For example, the following methods are used to connect the electrodes of the water electrolyzer:
When the connection is made of a stretchable cable, the water electrolyzer is fixed to the inner surfaces of the bottom walls of a pair of containers having a bottom wall at one end and the other end open, and the other end electrodes of these water electrolyzers The two are connected by a cable-like connection, and then a pair of containers are joined so as to accommodate the water electrolyzer.

  When the connection is made of a conductive rod, a water electrolysis tank is fixed to the inner surfaces of the bottom walls of a pair of containers having a bottom wall at one end and the other end open, and electrodes at the other end of these water electrolysis tanks The rods are connected to each other, and then a pair of containers are joined so that the water electrolyzer is contained inside.

  According to the present invention, the total number of unit cells can be doubled without increasing the number of unit cells stacked in one water electrolyzer. In addition, in order to generate the same amount of hydrogen as in the conventional apparatus, the number of unit cells stacked in one water electrolyzer can be halved. Therefore, assembly and maintenance of the apparatus can be easily performed.

  By using each container as an anode and a cathode, a current introduction terminal into the pressure container is not required, so that the configuration of the apparatus can be simplified and its reliability can be improved.

  Thus, it is possible to provide a high pressure vessel-accommodating water electrolysis hydrogen generator that is simple in construction and easy to assemble and that can generate a large amount of hydrogen.

  Hereinafter, the present invention will be specifically described based on examples. In the following description, the left and right refer to the left and right in FIG.

Example 1
In FIG. 1, a pair of left and right containers (21) (21 ') having the same shape and having a bottom wall at one end and an open end at the other end are prepared. Flange portions (23) and (23 ') are provided at the open ends of the containers (21) and (21'), respectively. The containers (21) and (21 ') are made integrally from a stainless steel ingot. The container (21) (21 ') may be made from steel or titanium ingots. Water electrolyzers (24) and (24 ') are respectively arranged inside the containers (21) and (21'), and are fixed with bolts at the bottom walls (22) and (22 ') of the containers. When the base plate (25) is interposed between the water electrolyzer (24) and the container bottom wall (22), as shown in FIG. 4, the base plate (25) is first attached to the container bottom wall (22) with a short bolt. (26) and then the outer edge of the end plate (13) of the water electrolysis tank (24) is fixed to the base plate (25) with a long bolt (27). When a base plate is not interposed between the water electrolysis tank (24) and the container bottom wall (22), as shown in FIG. 5, the end plate (13) of the water electrolysis tank (24) is placed on the container bottom wall (22). Fix the outer edge directly with the long bolt (27). Thus, the water electrolysis tank (24) is fixed to the container bottom wall (22), and the water electrolysis tank (24 ′) is fixed to the container bottom wall (22 ′).

  The water electrolysis tank (24) electrolyzes water using a polymer electrolyte membrane to generate oxygen at the anode and hydrogen at the cathode. The anode main electrode and the cathode main electrode arranged at both ends, and these A plurality of unit cells arranged in series between the main electrodes, a pair of end plates sandwiching the anode main electrode-multiple unit cells-cathode main electrode combination from both sides, and through the four corners of the pair of end plates The main body is mainly composed of an anode main electrode, a plurality of unit cells, and bolts and nuts for fastening the cathode main electrode from both sides. One cell is mainly composed of the anode side of the bipolar plate, the anode feeder, the electrode assembly film, the cathode feeder, and the cathode side of the adjacent bipolar plate. The water electrolyzer (24) has a water supply header, a hydrogen header, and an oxygen header that vertically penetrate the water electrolytic cell (24).

  In this way, a pair of left and right containers (21) (21 ') with water electrolyzers (24) and (24') are arranged together, and the flange portions (23) and (23 ') at the open ends are joined together. The pressure vessel (28) is formed from the pair of left and right vessels (21) and (21 ′). A pressure vessel (28) equipped with water electrolyzers (24) (24 ') is placed on a pair of left and right bases (29) (29').

  The left and right water electrolyzers (24) and (24 ′) in the pressure vessel (28) are connected to different power sources (30) and (30 ′), respectively. Each anode of the power source (30) (30 ') is connected to the water electrolyzer (24) (24') via the pressure terminal (31) (31 ') provided on the upper wall of the container (21) (21'). Each cathode is connected to each anode, and each cathode of the power source (30) (30 ') is connected to each cathode of the water electrolysis tank (24) (24') via the containers (21) (21 ').

  In the high-pressure vessel-accommodating water electrolysis hydrogen generator configured as described above, pure water is supplied from the water supply ports provided on both end walls of the pressure vessel (28) to the water electrolysis tanks (24) and (24 ′) of the pressure vessel (28). To the anode side. Hydrogen and entrained water are discharged into the pressure vessel (28) from the cathode side. Hydrogen is gas-liquid separated in the container and taken out from the upper gas outlet (32) provided in the upper part of the pressure container (28). Oxygen generated at the anode of the water electrolysis tank (24) and the remaining water are taken out from the end gas outlets (33) (33 ') provided on both end walls of the pressure vessel (28), and then outside the pressure vessel (28). It is sent to the gas-liquid separation tank and gas-liquid separation is performed in this tank. During maintenance or to prevent entrained water from losing the hydrogen gas storage space in the container, the accompanying water is withdrawn from the water outlet provided in the lower part of the pressure vessel (28) as necessary. . Further, when using the apparatus, the pressure on the anode side and the cathode side is adjusted by peripheral devices so that the seals provided on the electrode assembly membrane and the electrolytic cell are not broken.

Example 2
In FIG. 2, an insulating layer (35) is interposed between the flange portions (23) and (23 ′) of the pair of left and right containers (21) and (21 ′) to electrically insulate them. One power source (36) is provided, and its anode is connected to the anode of the water electrolyzer (24) through the left vessel (21), and the cathode of the power source (36) is connected to the right vessel (21 '). To the cathode of the water electrolyzer (24 ′) inside, and the water electrolyzers (24) and (24 ′) are electrically connected in series with the electrode assembly (34). The anode side outlet of the water electrolyzer (24) (24 ') is communicated with the inside of the pressure vessel (28).

  In the high pressure vessel storage type water electrolysis hydrogen generator of this configuration, pure water is supplied into the pressure vessel (28) from the water supply port provided at the upper right side of the center of the pressure vessel (28), and the water electrolysis tank ( 24) Store (24 ') in a container so that it is submerged. Oxygen generated at each anode of the water electrolyzers (24) and (24 ′) and the remaining water are discharged from the water electrolyzers (24) and (24 ′) into the pressure vessel (28). Oxygen is gas-liquid separated in the container and taken out from the upper gas outlet (32) provided on the left side of the upper part of the pressure vessel (25). Hydrogen and entrained water generated at each cathode of the water electrolyzer (24) (24 ') are taken out from the end central gas outlet (33) (33') provided at the center of both end walls of the pressure vessel (28). Then, it is sent to a gas-liquid separation tank outside the pressure vessel (28), and gas-liquid separation is performed in the tank. When the water in the pressure vessel (28) decreases, water is replenished from the water supply port, and the water electrolyzers (24) and (24 ′) are submerged. During maintenance, water is extracted from a water outlet provided in the lower portion of the pressure vessel (28). Other configurations are the same as those of the first embodiment.

Example 3
In FIG. 3, in the high-pressure vessel-accommodating water electrolysis hydrogen generator of this configuration, pure water is supplied from the water supply ports provided on both end walls of the pressure vessel (28) to the pressure vessel (28) as in the first embodiment. It supplies to the anode side of a water electrolysis tank (24) (24 '). Hydrogen and entrained water are discharged into the pressure vessel (28) from the cathode side. Hydrogen is gas-liquid separated in the container and taken out from the upper gas outlet (32) provided in the upper part of the pressure container (28). Oxygen generated at the anode of the water electrolysis tank (24) and the remaining water are taken out from the end gas outlets (33) (33 ') provided on both end walls of the pressure vessel (28), and then outside the pressure vessel (28). It is sent to the gas-liquid separation tank and gas-liquid separation is performed in this tank. During maintenance or to prevent entrained water from losing the hydrogen gas storage space in the container, the accompanying water is withdrawn from the water outlet provided in the lower part of the pressure vessel (28) as necessary. . Other configurations are the same as those of the first embodiment.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a vertical longitudinal sectional view schematically showing a high-pressure container-accommodating water electrolysis hydrogen generator of Example 1. It is a vertical longitudinal cross-sectional view which shows schematically the high pressure vessel storage type water electrolysis hydrogen generator of Example 2. It is a vertical longitudinal cross-sectional view which shows schematically the high pressure vessel storage type water electrolysis hydrogen generator of Example 3. 4a is a longitudinal sectional view showing a fixed state of the water electrolysis tank in the high pressure vessel storage type water electrolysis hydrogen generator of Example 1, and FIG. 4a is a transverse sectional view thereof. FIG. 5a is a longitudinal sectional view showing a fixed state of the water electrolysis tank in the high pressure vessel storage type water electrolysis hydrogen generator of Example 1, and FIG. 5a is a transverse sectional view thereof. It is a vertical longitudinal cross-sectional view which shows schematically the conventional high pressure vessel storage type water electrolysis hydrogen generator.

Explanation of symbols

(22) (22 '): Bottom wall
(21) (21 '): Container
(23) (23 '): Flange
(24) (24 '): Water electrolyzer
(28): Pressure vessel
(30) (30 '): Power supply
(31) (31 '): Pressure terminal
(32): Upper gas outlet
(33) (33 '): End gas outlet
(34): Polar assembly
(35): Insulating layer
(36): Power supply

Claims (5)

A water electrolyzer is placed inside a pair of left and right containers that have a bottom wall at one end and the other end is open, and are fixed at the bottom wall of the container. A container-accommodating water electrolyzer in a water electrolysis hydrogen generator formed by forming a pressure vessel. A pair of left and right containers are electrically insulated, the water electrolyzers in each container are electrically connected in series, and the anode of the power source is connected to the anode of the water electrolyzer in the interior through one container, 2. The container-encased water electrolyzer in a water electrolysis hydrogen generator according to claim 1, wherein the cathode of the power source is connected to the cathode of the water electrolyzer inside the other container through the other container. The water electrolysis hydrogen generator according to claim 1 or 2, wherein the pressure vessel is provided with an oxygen outlet through which the anode side outlet of the water electrolyzer in each vessel and the inside of the pressure vessel communicate, and oxygen generated at each anode is extracted. Container storage type water electrolyzer. The water electrolysis hydrogen generator according to claim 1 or 2, wherein the pressure vessel is provided with a hydrogen outlet through which the cathode side outlet of the water electrolyzer in each vessel communicates with the inside of the pressure vessel, and hydrogen generated at each cathode is extracted. Container storage type water electrolyzer. A water electrolysis tank is fixed to the inner surfaces of the bottom walls of a pair of containers having a bottom wall at one end and the other end open, and the other end electrode of these water electrolysis tanks is connected to a pressure terminal provided on the container wall. Assembling of the container-accommodating water electrolyzer in the water electrolysis hydrogen generator that connects or connects the electrodes on the other end, and then connects the pair of containers so that the open ends face each other so that the water electrolyzer is contained inside Method.

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