JP2017002345A - Water electrolyzer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a water electrolyzer applicable to a domestic hydrogen station.SOLUTION: A water electrolyzer for electrolyzing water includes: a cylindrical pressure tank into which water is charged; a plurality of plate-shaped partitions which are arranged radially from the center to the outer wall of the pressure tank when viewed from above the pressure tank and partition the inside of the pressure tank into parts having the same volume; a cylindrical partition which is concentrically arranged with the pressure tank when viewed from above the pressure tank and partitions the inside of the pressure tank so that the ratio of its outer volume to its inner volume is 2:1; a plurality of negative electrodes which are respectively arranged in each space outside the cylindrical partition; a plurality of positive electrodes which are respectively arranged in each space inside the cylindrical partition; and an orifice and a pressure control valve which are provided as outlets of hydrogen gas and oxygen gas generated from the negative electrode and the positive electrode, respectively.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a water electrolysis apparatus applicable to a domestic hydrogen station.

  Recently, there have been an increasing number of cases where stationary fuel cells are installed as household power sources, and fuel cell vehicles have been put into practical use. Since these fuel cells use hydrogen gas as a fuel, there is an increasing interest in devices that produce and store hydrogen gas at home.

Patent Document 1 describes the following invention.
1. A reformer for reforming the hydrogen-containing fuel to obtain a reformed gas, a hydrogen purifier for purifying high-purity hydrogen gas by removing unnecessary substances from the reformed gas, and storing the hydrogen gas, A first hydrogen storage device for supplying the hydrogen gas to a stationary fuel cell; a second hydrogen storage device for storing the hydrogen gas and supplying the hydrogen gas to a fuel cell vehicle; and the hydrogen gas And a control device that controls switching between the first hydrogen storage unit and the second hydrogen storage unit.
2. A reformer for reforming the hydrogen-containing fuel to obtain a reformed gas, a hydrogen purifier for purifying high-purity hydrogen gas by removing unnecessary substances from the reformed gas, and storing the hydrogen gas, Hydrogen gas comprising a first hydrogen storage device for supplying the hydrogen gas to a stationary fuel cell, and a second hydrogen storage device for storing the hydrogen gas and supplying the hydrogen gas to a fuel cell vehicle A method of operating a production power generation system, the step of detecting the concentration of the hydrogen gas purified by the hydrogen purifier, and the first hydrogen storage device when the detected hydrogen concentration is less than a predetermined value Supplying the hydrogen gas to the second hydrogen storage device when the detected hydrogen concentration is equal to or higher than a predetermined value. Manufacturing power generation system The method of operation.

JP 2005-293959 A

  A fuel cell vehicle is provided with a high-pressure tank that is filled with hydrogen gas at a high pressure in order to secure a distance that can be traveled with a single replenishment of hydrogen gas. Since hydrogen gas is consumed, a means for supplying hydrogen gas to this high-pressure tank is also required, and it is preferable to use an electrolyzer for water that can produce hydrogen gas by itself. In an electrolysis apparatus for water, an acidic aqueous solution, an alkaline aqueous solution, or a neutral aqueous solution is usually used. However, since water is electrolyzed, it can be easily replenished in a general household.

  However, it is difficult to install a domestic hydrogen station in a general household (especially a remote island or a mountain village) in terms of facility cost and scale, and development of a water electrolysis apparatus for that purpose is also delayed.

  Then, an object of this invention is to provide the electrolyzer of water applicable to a domestic hydrogen station.

The present invention is an apparatus for electrolyzing water,
A cylindrical pressure tank into which water is introduced;
A plurality of plate-like partitions that are arranged radially from the center toward the outer wall as viewed from above the pressure tank and partition the inside of the pressure tank so that the respective volumes are the same;
A cylindrical partition arranged concentrically when viewed from above the pressure tank, and partitioning the inside of the pressure tank so that the outer volume: inner volume is 2: 1;
A plurality of -electrodes disposed outside each of the cylindrical partitions and in each space partitioned by the plate-shaped partition;
A plurality of + electrodes arranged inside each of the cylindrical partitions and each space partitioned by the plate-shaped partition;
An orifice for hydrogen gas provided as an outlet for hydrogen gas generated from the electrode;
An orifice for oxygen gas provided as an outlet for oxygen gas generated from the + electrode;
A hydrogen gas pressure regulating valve for discharging the hydrogen gas that has passed through the hydrogen gas orifice;
It is an electrolyzer for water having an oxygen gas pressure regulating valve for discharging oxygen gas that has passed through the oxygen gas orifice.

  ADVANTAGE OF THE INVENTION According to this invention, the electrolyzer of water applicable to a domestic hydrogen station can be provided.

It is AA sectional view taken on the line which shows the structural example of the electrolysis apparatus of the water which concerns on this invention. It is a BB line sectional view showing the example of composition of the water electrolysis device concerning the present invention. FIG. 2 is a cross-sectional view taken along line AA showing a state where a pressure difference is generated between hydrogen gas and oxygen gas in the apparatus of FIG. 1.

  The present invention is an apparatus for electrolyzing water. In an electrolysis apparatus for water, an acidic aqueous solution, an alkaline aqueous solution, or a neutral aqueous solution is usually used, and among these, an alkaline aqueous solution is preferably used. Hereinafter, it demonstrates as an electrolysis apparatus of water using alkaline aqueous solution.

  1 and 2 show a configuration example of a water electrolysis apparatus according to the present invention. This electrolyzer for water has a pressure tank composed of a housing 1 and an upper lid 2, and a negative electrode 10a and a positive electrode 10b disposed therein. Then, water can be electrolyzed by energizing the negative electrode 10a and the positive electrode 10b with the alkaline aqueous solution present inside the pressure tank.

  As shown in FIG. 2, the inside of the pressure tank casing 1 has a plurality of plate-like partitions 11 arranged radially from the center to the outer wall as viewed from above the pressure tank so that the respective volumes are the same. It is partitioned. The number of the plate-like partitions 11 can be appropriately set, but is preferably 4 to 12, more preferably 6 to 10, for example, 8 as shown in FIG. it can.

  In the casing 1 of the pressure tank, as shown in FIG. 2, a cylindrical partition 12 is disposed concentrically when viewed from above the pressure tank. By this partitioning, the inside of the housing 1 of the pressure tank can be separated into a negative electrode 10a side where hydrogen gas is generated by water electrolysis and a positive electrode 10b side where oxygen gas is generated. The position where the cylindrical partition 12 is arranged is a position where the outside volume of the cylindrical partition 12: the inside volume is 2: 1. By doing so, the volume of the outside: inside of the cylindrical partition 12 becomes the same as the volume ratio of the generated hydrogen gas and oxygen gas, and the gas pressures outside and inside the cylindrical partition 12 are theoretically the same. The water level will be the same.

  Electrodes are arranged in the spaces partitioned by the plate-like partition 11 and the cylindrical partition 12. Specifically, the negative electrode 10a is disposed outside the cylindrical partition 12 and in each space partitioned by the plate partition 11, and the positive electrode 10b is disposed inside the cylindrical partition 12 and the plate partition. 11 is arranged in each space partitioned by 11.

  The plate-like partition 11 and the cylindrical partition 12 need only be formed of a material that can partition the inside. However, since the water is electrolyzed, the plate-like partition 11 and the cylindrical partition 12 are at least sandwiched between the -electrode 10a and the + electrode 10b. The existing cylindrical partition 12 is preferably formed of a porous diaphragm 13.

  The -electrode 10a and the + electrode 10b are fixed to a substrate 30 installed horizontally inside the casing 1 of the pressure tank, and the substrate 30 is preferably connected to the upper lid 1 via a holding rod. . The holding rod may be of one type, but is preferably divided into a negative electrode holding rod 31a and a positive electrode holding rod 31b. By doing so, the -electrode holding bar 31a and the + electrode holding bar 31b can be used as wiring to each electrode, and the -electrode is passed through a power receiving terminal (not shown) for receiving power from the outside. Power can be supplied to the 10a and + electrodes 10b. It can also be used to hold the plate-like partition 11 between electrodes of the same polarity. The number of holding rods can be set as appropriate, but it is made to correspond one-to-one by using the same number of -electrode holding rods 31a as the -electrodes 10a and the same number of + electrode holding rods 31b as the + electrodes 10b. Can do.

  As shown in FIG. 1, it is preferable that the board | substrate 30 with which-electrode 10a and + electrode 10b were fixed is arrange | positioned in the inside of the housing | casing 1 of a pressure tank in multiple steps. By doing so, the inner diameter of the pressure tank can be reduced. In this case, the substrate 30 is preferably provided with a gap through which hydrogen gas and oxygen gas generated from the lower -electrode 10a and + electrode 10b pass. Furthermore, it is preferable to provide a guide 32 that guides hydrogen gas and oxygen gas generated from the lower -electrode 10a and + electrode 10b to a gap provided in the substrate. The guide 32 can also have a role of holding the substrate.

  The casing 1 of the pressure tank is preferably provided with a heating facility 5 for heating the inside of the pressure tank. By carrying out like this, the alkaline aqueous solution which exists in the inside of a pressure tank can be controlled to fixed temperature, and alkaline aqueous solution can be made to convect.

  The casing 1 of the pressure tank is preferably provided with a water supply port 3 for supplying water to the inside of the pressure tank. By carrying out like this, the water reduced by electrolyzing water in a pressure tank can be replenished. In addition, even if it uses any of acidic aqueous solution, alkaline aqueous solution, and neutral aqueous solution, since it is water that is electrolyzed, it can be easily replenished in a general household.

  Further, it is preferable to have a mechanism for detecting the amount of water present inside the casing 1 of the pressure tank and automatically replenishing the inside of the pressure tank when the water is reduced to a predetermined amount. For example, the total weight of the pressure tank is measured in real time, and when the amount of water reduction reaches a limit line (immediately before the −electrode 10a and the + electrode 10b are exposed), a mechanism for supplying a fixed amount of water is used. be able to.

  A hydrogen gas orifice 21a is provided as an outlet for hydrogen gas generated from the electrode 10a, and a hydrogen gas pressure adjusting valve 22a for discharging the hydrogen gas that has passed through the hydrogen gas orifice 21a is provided. Then, hydrogen gas accumulates in a state where the hydrogen gas pressure adjustment valve 22a is closed, and when the hydrogen gas pressure reaches a set pressure, the hydrogen gas pressure adjustment valve 22a opens and enters the hydrogen gas separation tank 20a. Guided and separated into hydrogen gas and water. On the other hand, an oxygen gas orifice 21b is provided as an outlet for oxygen gas generated from the + electrode 10b, and an oxygen gas pressure adjusting valve 22b for discharging oxygen gas that has passed through the oxygen gas orifice 21b is provided. Yes. Then, oxygen gas accumulates with the oxygen gas pressure regulating valve 22b closed, and when the oxygen gas pressure reaches the set pressure, the oxygen gas pressure regulating valve 22b opens and enters the oxygen gas separation tank 20b. Guided and separated into oxygen gas and water. It is preferable that hydrogen gas and oxygen gas can be pressurized to 30 atm and a maximum pressure of 50 atm.

  If there is a pressure difference between the hydrogen gas and oxygen gas accumulated in the pressure tank, there will be a difference in the level of each alkaline aqueous solution, and the level of the alkaline aqueous solution on the lower pressure side will rise and reach the orifice. Conceivable. For example, FIG. 3 shows a state where the pressure of hydrogen gas has increased. However, since the orifice allows gas to pass but not liquid, the pressure of the gas in the region where the liquid level has risen (oxygen gas in FIG. 3) increases as a result, and the gas accumulated in the region where the liquid level has fallen ( In FIG. 3, the lowering of the liquid level can be stopped by pressing hydrogen gas). As a result, it is possible to prevent electrode exposure due to a step on an abnormal liquid surface.

  Further, in the present invention, it is preferable to provide a hydrogen gas region safety valve 23a for releasing the pressure in the region where hydrogen gas is accumulated and an oxygen gas region safety valve 23b for releasing the pressure in the region where oxygen gas is accumulated. By doing so, when the internal gas pressure becomes high due to some abnormality, the safety valve provided in each region is opened, power transmission is shut down, and operation can be stopped.

  The hydrogen gas orifice 21a, the oxygen gas orifice 21b, the hydrogen gas pressure adjusting valve 22a, the oxygen gas pressure adjusting valve 22b, the hydrogen gas safety valve 23a, and the oxygen gas safety valve 23b are provided on the upper lid 2 of the pressure tank. It is preferable. Further, since the substrate 30 to which the negative electrode 10a and the positive electrode 10b are fixed is also connected to the upper lid 1, all parts are attached to the upper lid 2 of the pressure tank as a unit. It becomes easy to exchange by.

  Note that the surfaces in contact with the alkaline aqueous solution, hydrogen gas, and oxygen gas are preferably all subjected to insulation treatment.

  The water electrolysis device according to the present invention is connected to a power generation device using natural energy such as a solar power generation device, and can receive power at a power receiving terminal provided on the upper lid 2 of the pressure tank and transmit power to each electrode. It is preferable to do. In this way, water can be electrolyzed even at home using the solar light energy irradiated on the solar panel installed on the roof of the house. The power generation capacity of the solar power generation device can be operated at about 3 to 4 kW, for example. When solar energy is insufficient at night or on rainy days, the electrodes to be energized are limited in consideration of efficiency and the like, and a small amount of hydrogen gas and oxygen gas can be produced.

  According to the present invention as described above, it is possible to provide a small-sized and high-pressure water electrolysis device (hydrogen generation device) that can be applied to a domestic hydrogen station, and hydrogen gas and oxygen gas can be easily used at home. Therefore, it is possible to provide a place for studying how to use hydrogen gas and oxygen gas. The main aim of the present invention is to supply hydrogen to fuel cell vehicles (FCV vehicles) and to utilize hydrogen and oxygen for regional revitalization. The utilization is (1) realization of a healthy society, (2 There are various needs such as)) cultivation of vegetables, flowers, fruits, etc., and (3) aquaculture / livestock production.

DESCRIPTION OF SYMBOLS 1 Case 2 Top cover 3 Water supply port 5 Heating equipment 10a-Electrode 10b + Electrode 11 Plate-shaped partition 12 Cylindrical partition 13 Diaphragm 20a Hydrogen gas separation tank 20b Oxygen gas separation tank 21a Hydrogen gas orifice 21b Oxygen gas orifice 22a Hydrogen Gas pressure adjusting valve 22b Oxygen gas pressure adjusting valve 23a Hydrogen gas region safety valve 23b Oxygen gas region safety valve 30 Substrate 31a-Electrode holding rod 31b + Electrode holding rod 32 Guide

Claims (8)

A device for electrolyzing water,
A cylindrical pressure tank into which water is introduced;
A plurality of plate-like partitions that are arranged radially from the center toward the outer wall as viewed from above the pressure tank and partition the inside of the pressure tank so that the respective volumes are the same;
A cylindrical partition arranged concentrically when viewed from above the pressure tank, and partitioning the inside of the pressure tank so that the outer volume: inner volume is 2: 1;
A plurality of -electrodes disposed outside each of the cylindrical partitions and in each space partitioned by the plate-shaped partition;
A plurality of + electrodes arranged inside each of the cylindrical partitions and each space partitioned by the plate-shaped partition;
An orifice for hydrogen gas provided as an outlet for hydrogen gas generated from the electrode;
An orifice for oxygen gas provided as an outlet for oxygen gas generated from the + electrode;
A hydrogen gas pressure regulating valve for discharging the hydrogen gas that has passed through the hydrogen gas orifice;
An electrolyzer for water having an oxygen gas pressure regulating valve for discharging oxygen gas that has passed through the oxygen gas orifice. further,
A hydrogen gas region safety valve for releasing the pressure of the region where the hydrogen gas accumulates;
The water electrolysis apparatus according to claim 1, further comprising an oxygen gas region safety valve that relieves pressure in a region where the oxygen gas accumulates.   The hydrogen gas orifice, the oxygen gas orifice, the hydrogen gas pressure regulating valve, the oxygen gas pressure regulating valve, the hydrogen gas safety valve, and the oxygen gas safety valve are provided on an upper lid of the pressure tank. The water electrolyzer according to claim 2.   The plurality of − electrodes and the plurality of + electrodes are fixed on a substrate installed horizontally in the pressure tank, and the substrate is connected to the upper lid via a holding rod. The electrolyzer for water according to any one of the above.   The water electrolysis apparatus according to claim 4, wherein a plurality of substrates on which a plurality of − electrodes and a plurality of + electrodes are fixed are arranged in a multistage manner inside the pressure tank.   The water electrolysis apparatus according to any one of claims 1 to 5, wherein a heating facility for heating the inside of the pressure tank is provided around the pressure tank.   The water electrolysis apparatus according to any one of claims 1 to 6, wherein the pressure tank is provided with a water supply port for supplying water to the inside of the pressure tank.   The water electrolysis apparatus according to claim 7, further comprising a mechanism for detecting the amount of water present in the pressure tank and replenishing the inside of the pressure tank when water is reduced to a predetermined amount.

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