JP2010001188A - Hydrogen production apparatus and fuel cell - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hydrogen production apparatus capable of simply and efficiently producing hydrogen and to provide a fuel cell using the hydrogen production apparatus as a hydrogen supply source. <P>SOLUTION: The hydrogen production apparatus comprises a hydrogen generating substance hold container which holds a hydrogen generating substance, a water hold container which holds water, a water supply part which supplies water from the water hold container to the hydrogen generating substance hold container, a hydrogen delivery part which delivers hydrogen from the hydrogen generating substance hold container, a gas/liquid separation part for separating water from a hydrogen/water mixture discharged from the hydrogen-generating substance hold container, and a water recovery part for recovering water separated in the gas/liquid separation part in the water hold container, wherein the water hold container has inflexibility and is sealed so that its inside is evacuated when water is fed into the hydrogen-generating substance hold container, and the water recovery part sucks water from the gas/liquid separation part to recover the water in the water hold container when the water hold container is evacuated. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a hydrogen production apparatus for producing hydrogen by reacting a hydrogen generating substance and water, and a fuel cell using the hydrogen production apparatus as a hydrogen supply source.

  In recent years, with the widespread use of cordless devices such as personal computers and mobile phones, batteries that are power sources are increasingly required to be smaller and have higher capacities. Currently, lithium ion secondary batteries have been put into practical use as batteries that have high energy density and can be reduced in size and weight, and demand for portable power sources is increasing. However, this lithium ion secondary battery has a problem that it cannot guarantee a sufficient continuous use time for some cordless devices.

  In order to solve the above problems, for example, development of fuel cells such as polymer electrolyte fuel cells (PEFC) is underway. The fuel cell can be used continuously if fuel and oxygen are supplied. A PEFC that uses a solid polymer electrolyte as an electrolyte, oxygen in the air as a positive electrode active material, and fuel as a negative electrode active material has attracted attention as a battery having a higher energy density than a lithium ion secondary battery.

  Regarding fuels used in PEFC, hydrogen, methanol, and the like have been proposed and various developments have been made. However, PEFCs using hydrogen as a fuel are expected from the viewpoint of high energy density.

  And as a method of supplying hydrogen to a fuel cell such as PEFC, for example, a method of supplying hydrogen produced by a hydrogen production apparatus capable of generating hydrogen by reacting a hydrogen generating material serving as a hydrogen source with water Is being considered. In such a hydrogen production apparatus, for example, a tank for storing water and a container for storing a hydrogen generating substance and reacting the hydrogen generating substance with water are provided. The tank for storing the water Then, water is supplied to a container (reaction container) containing the hydrogen generating substance, the hydrogen generating substance and water are reacted in the container, and the generated hydrogen is supplied to the fuel through a hydrogen outlet pipe provided in the container. A mechanism for supplying the battery is employed.

  However, during the reaction between the hydrogen generating substance and water, unreacted water is ejected together with hydrogen and discharged outside the reaction vessel. Therefore, in the conventional hydrogen production apparatus, it is necessary to hold an amount of water that is considerably larger than the amount necessary for the reaction in the water storage tank. In addition, when hydrogen containing such a large amount of water is supplied to the fuel cell, the fuel cell may become clogged.

  From the above circumstances, in a hydrogen production apparatus having a mechanism for generating hydrogen by reaction of a hydrogen generating substance and water, treatment of unreacted water discharged from the reaction vessel together with the generated hydrogen is required. For example, Patent Document 1 discloses that a mixture of hydrogen and water (steam) discharged from a reaction vessel is returned to a water storage tank, mixed with water in the tank, and subjected to heat exchange to perform heat exchange. There has been proposed a hydrogen generator having a mechanism in which water vapor is used as water and hydrogen in the mixture is taken out from a discharge pipe provided in the upper part of the tank and supplied to a fuel cell or the like. According to the apparatus described in Patent Document 1, water vapor discharged from the reaction vessel together with hydrogen can be returned to the water in the water storage tank and supplied again to the reaction vessel, so that water can be efficiently used for hydrogen production. .

JP 2004-149394 A

  However, the water storage tank of Patent Document 1 needs to include a pipe for supplying water, a pipe for returning a mixture of hydrogen and water discharged from the reaction vessel, and a pipe for discharging hydrogen. The structure becomes complicated. Moreover, since the mixture of high-temperature hydrogen and water is directly returned to the water storage tank, the water temperature in the water storage tank rises as hydrogen is produced. Therefore, the water storage tank needs to be made of a material having heat resistance.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a hydrogen production apparatus capable of producing hydrogen easily and efficiently and a fuel cell using the hydrogen production apparatus as a hydrogen supply source. .

  The hydrogen production apparatus according to the present invention includes a hydrogen generating material storage container that stores a hydrogen generating material, a water storage container that stores water, and a water supply for supplying water from the water storage container to the hydrogen generating material storage container. A hydrogen deriving unit for deriving hydrogen from the hydrogen generating material storage container, and a gas-liquid separation unit for separating water from a mixture containing hydrogen and water discharged from the hydrogen generating material storage container; And a water recovery unit for recovering the water separated by the gas-liquid separation unit into the water storage container, wherein the water storage container has inflexibility and the hydrogen generating substance. When water is supplied to the storage container, the inside of the water storage container is sealed so that the pressure is reduced, and the water recovery unit sucks water from the gas-liquid separation unit by reducing the pressure of the water storage container. Water to the water container Characterized in that it yield.

  The fuel cell of the present invention is characterized in that the hydrogen production apparatus of the present invention is used as a hydrogen supply source.

  ADVANTAGE OF THE INVENTION According to this invention, the hydrogen production apparatus which can produce hydrogen simply and efficiently can be provided. That is, in the hydrogen production apparatus of the present invention, the negative pressure generated when water is supplied from the water storage container to the hydrogen generating substance storage container is used to collect the water separated by the gas-liquid separation unit in the water storage container. is doing. Therefore, an auxiliary device for collecting water in the water container is not necessary, and a simple device can be obtained.

  Further, when the water supply from the water storage container is stopped, no negative pressure is generated inside the water storage container, so that the water stored in the gas-liquid separation unit cannot be recovered. However, in the present invention, by separately providing a water recovery unit that functions even when the water supply is stopped, water can be recovered from the gas-liquid separation unit to the water container even when the water supply is stopped.

  The hydrogen production apparatus according to the present invention includes a hydrogen generating material storage container that stores a hydrogen generating material, a water storage container that stores water, and a water supply for supplying water from the water storage container to the hydrogen generating material storage container. A hydrogen deriving unit for deriving hydrogen from the hydrogen generating material storage container, and a gas-liquid separation unit for separating water from a mixture containing hydrogen and water discharged from the hydrogen generating material storage container; And a water recovery part for recovering the water separated by the gas-liquid separation part into the water storage container.

  The water storage container has inflexibility, and is sealed so that the interior of the water storage container is depressurized when water is supplied to the hydrogen generating substance storage container. When the pressure is reduced, water is sucked from the gas-liquid separator, and water is collected into the water container. As a result, the negative pressure generated when water is supplied from the water storage container to the hydrogen generating substance storage container can be used to collect the water separated by the gas-liquid separator in the water storage container. An auxiliary device for collecting in a container is not required, and a hydrogen production apparatus that can produce hydrogen simply and efficiently can be provided.

  In addition, the water recovery unit includes a first water recovery unit and a second water recovery unit, and the first water recovery unit draws water from the gas-liquid separation unit when the water container is decompressed. The second water recovery unit sucks water from the gas-liquid separation unit when the water storage container is in a non-depressurized state and collects water into the water storage container. Is preferably recovered. By providing the second water recovery unit, water can be recovered from the gas-liquid separation unit to the water storage container even when the water supply from the water storage container is stopped and no negative pressure is generated inside the water storage container. it can.

  The second water recovery unit preferably includes a pump and a flow path switching unit. Thereby, a 2nd water collection | recovery part can be made into a simple structure.

  Moreover, it is preferable that the said water storage container is not provided with opening parts other than the opening part to which the said water supply part and the said water collection | recovery part are connected, respectively. Thereby, the airtightness in a water storage container can be improved.

  The hydrogen production apparatus of the present invention further includes a cooling unit for cooling the mixture before the mixture containing hydrogen and water discharged from the hydrogen generating substance storage container enters the gas-liquid separation unit. It is preferable. Thereby, separation of water and hydrogen in the gas-liquid separation unit can be performed more easily.

  Moreover, it is preferable that the said water collection | recovery part is arrange | positioned below the said gas-liquid separation part with respect to the perpendicular direction. Thereby, in addition to negative pressure, gravity can also be utilized and the water isolate | separated by the gas-liquid separation part can be collect | recovered in a water storage container.

  The hydrogen generating substance storage container stores a hydrogen generating substance, and the hydrogen generating substance is selected from the group consisting of aluminum, silicon, zinc, magnesium, and an alloy mainly composed of one or more of these metal elements. Preferably, the at least one metal. This is because these substances can easily react with water and generate hydrogen efficiently.

  Moreover, it is preferable that the said hydrogen generating substance storage container further contains the exothermic substance which carries out an exothermic reaction with water. Thereby, reaction of water and a hydrogen generating substance can be started easily.

  Moreover, it is preferable that the said exothermic substance is unevenly distributed and arrange | positioned in the vicinity of the opening part of the said water supply part. Thereby, the time until hydrogen is generated by the reaction of water and the hydrogen generating substance can be shortened.

  The fuel cell of the present invention is characterized in that the hydrogen production apparatus of the present invention is used as a hydrogen supply source.

  Hereinafter, embodiments of the hydrogen production apparatus of the present invention will be described with reference to the drawings.

(Embodiment 1)
FIG. 1 is a partial cross-sectional schematic view showing an example of the hydrogen production apparatus of the present invention. FIG. 1 shows an example of the hydrogen production apparatus of the present invention, and the hydrogen production apparatus of the present invention is not limited to the one shown in FIG. In FIG. 1, 1 is a hydrogen generating substance storage container, 10 is a hydrogen generating substance, 1a is a hydrogen outlet pipe, 1b is a water supply pipe, 2 is a water storage container, 20 is water, 2a is a water supply pipe, 2b is water recovery A pipe 3 is a desorption part for connecting the hydrogen production apparatus main body 1 and the hydrogen generating substance container 1 or the water container 2, 4 is a heat insulating material, 5 is a pump, 6 is a cooling part, and 7 is a gas-liquid separation part. It is. Further, the water supply pipes 1b and 2a and the pump 5 constitute the water supply unit of the present embodiment. Furthermore, the hydrogen lead-out part of this embodiment is comprised by the hydrogen lead-out pipe 1a.

  In FIG. 1, only the hydrogen generating substance storage container 1, the water storage container 2, the heat insulating material 4, and the gas-liquid separator 7 are shown in cross section.

  In the hydrogen production apparatus of the present invention, water is supplied from the water container 2 to the hydrogen generating substance container 1 and hydrogen is produced by reacting the hydrogen generating substance and water in the hydrogen generating substance container 1. Therefore, the hydrogen generating substance storage container 1 also serves as a reaction container for the hydrogen generating substance and water. Hydrogen generated in the hydrogen generating substance storage container 1 is supplied to a device (such as a fuel cell) that requires hydrogen through a hydrogen outlet pipe 1a.

  As described above, when hydrogen is generated by reacting the hydrogen generating substance with water in the hydrogen generating substance storage container 1, unreacted water is ejected together with hydrogen, and the mixture with hydrogen is supplied from the hydrogen outlet pipe 1a. As a result, the hydrogen generating substance storage container 1 as a reaction container is discharged to the outside. However, the hydrogen production apparatus of the present invention has the gas-liquid separation unit 7, and the mixture of water and hydrogen discharged from the hydrogen generating substance storage container 1 is separated into water and hydrogen by the gas-liquid separation unit 7. The separated water can be recovered in the water container 2.

  1 includes a water separation container 7a for separating water and hydrogen, a hydrogen introduction pipe 7b for introducing a mixture of water and hydrogen into the water separation container 7a, and a water separation container. A hydrogen discharge pipe 7c for discharging the hydrogen separated in 7a and a water recovery pipe 7d for returning the water separated in the water separation container 7a to the water storage container 2 are constituted. Of the mixture of water and hydrogen flowing in from the hydrogen introduction pipe 7b, the water falls below the water separation container 7a by gravity and is separated from hydrogen. The separated water is recovered in the water storage container 2 through the water recovery pipes 7d and 2b. Thus, in this embodiment, the water recovery unit that returns the water separated from the mixture of water and hydrogen discharged from the hydrogen generating material storage container 1 to the water storage container 2 is used as the gas-liquid separation unit 7 and the water storage container. 2 is constituted by water recovery pipes 2b and 7d connected to each other.

  As described above, in the apparatus of the present invention, the unreacted water discharged from the hydrogen generating substance storage container 1 together with the generated hydrogen is recovered in the water storage container 2 by the action of the gas-liquid separation unit 7 to generate hydrogen again. Since it can be used for the reaction, the amount of water used can be reduced substantially, and the amount of water stored in the water storage container 2 can be reduced, thereby reducing the volume and weight of the hydrogen production apparatus. And can be made compact.

  For example, when a hydrogen production apparatus is used as a fuel source of a fuel cell, if a large amount of water is supplied into the fuel cell together with hydrogen, water may be clogged in the fuel cell. However, according to the hydrogen production apparatus of the present invention, the gas-liquid separation unit 7 can supply water to the fuel cell after removing water from the mixture of water and hydrogen discharged from the hydrogen generating substance storage container 1, It is also possible to prevent the clogging.

  Furthermore, in the hydrogen production apparatus of the present invention, water and hydrogen are separated in the gas-liquid separator 7 separate from the water container 2, so that the pipe connected to the water container 2 is the water supply pipe 2 a and Two water recovery pipes 2b may be used, and a hydrogen lead-out pipe required when water and hydrogen are separated in the water storage container 2 can be omitted, so that the structure of the water storage container 2 is simplified. Moreover, as shown in FIG. 1, it is preferable that the gas-liquid separation unit 7 is separated from the hydrogen generating material storage container 1 as well as the water storage container 2, and in this way, the hydrogen generating material storage container 1 and the water storage container 2 can be made into a simpler structure, and they can be made compact.

  The water storage container 2 of the present invention is composed of an inflexible container. When water is supplied from the water storage container 2 to the hydrogen generating substance storage container 1 by using an inflexible container, the pressure inside the water storage container 2 decreases. Due to this pressure drop, water can be sucked from the gas-liquid separator through the water recovery tubes 7d and 2b. Therefore, a simple hydrogen production apparatus can be obtained without requiring an apparatus for recovering water from the gas-liquid separation unit 7.

  Moreover, the water container 2 does not have an opening other than the opening to which the water supply pipe 2a and the water recovery pipe 2b are connected. Thereby, the airtightness in the water storage container 2 can be improved more.

  As a means for returning water from the gas-liquid separation unit 7 to the water storage container 2, it is possible to return the water by its own weight, but in this case, the gas-liquid separation unit 7 is more than the water storage container 2 with respect to the vertical direction. Must be installed at the top. However, in the hydrogen production apparatus of the present invention, water is drawn in due to a pressure drop inside the water storage container 2, so that there are no restrictions on the installation positions of the gas-liquid separator 7 and the water storage container 2. However, the water recovery pipe 7d is preferably installed below the gas-liquid separator 7 in the vertical direction. Thereby, the water stored in the lower part of the gas-liquid separation part 7 can be returned to the water container 2 by the water recovery pipe 7d.

  Further, in the apparatus of FIG. 1, the hydrogen generating substance storage container 1 and the water storage container 2 are detachably connected to the apparatus main body via a detachable part 3. Thus, in the hydrogen production apparatus of the present invention, it is preferable that the hydrogen generating substance storage container 1 and / or the water storage container 2 are detachably attached to the main body. The main body section (apparatus main body section) here refers to a portion other than the hydrogen generating substance storage container 1 and the water storage container 2 (the heat insulating material 4, the pump 5, the pipe portion above the desorption section 3 in FIG. The separation part 7 is included).

  When hydrogen is generated by reacting the hydrogen generating substance with water in the hydrogen generating substance storage container 1, the hydrogen generating substance 10 stored in the hydrogen generating substance storage container 1 is changed into a reaction product, and water is stored. The water 20 contained in the container 2 is consumed and decreases. If the apparatus has the detachable hydrogen generating substance storage container 1 and / or the water storage container 2 as described above, the hydrogen generating substance 10 in the hydrogen generating substance storage container 1 reacts to generate hydrogen. After that, the hydrogen generating substance storage container 1 and the water storage container 2 are removed from the desorption part 3, and a new hydrogen generating substance storage container that stores the hydrogen generating substance, and a new water storage container that stores the water, Is repeatedly attached to the main body by the desorption part 3 so that hydrogen can be repeatedly generated. Therefore, by preparing a spare hydrogen generating substance storage container or water storage container, it is possible to continuously operate in places where it is difficult to obtain hydrogen generating substance or water, or where it is difficult to supply hydrogen generating substance or water to the device. It is possible to provide a highly portable apparatus capable of producing hydrogen.

  Further, it is also preferable that the hydrogen generating substance storage container 1 and the water storage container 2 are integrated to form an integral container, which can be attached to and detached from the apparatus main body, thereby making it easier to replace the container. .

  Although there is no restriction | limiting in particular as the desorption part 3, For example, the site | part (pipe etc.) shape | molded cylindrically in the apparatus main body part side is provided, and each pipe | tube ( The hydrogen lead-out pipe 1a, the water supply pipes 1b, 2a, etc.) are inserted, and the connection part (the pipe insertion part) is sealed with a packing such as a resin circular ring to prevent leakage of hydrogen or water. A configuration can be employed.

  In addition, the hydrogen production apparatus preferably has a cooling unit 6 for cooling the mixture of water and hydrogen discharged from the hydrogen generating substance storage container 1. In the apparatus of the present invention, since the inside of the hydrogen generating substance storage container 1 can be at a temperature close to the boiling point of water, the water discharged as a mixture with hydrogen partially becomes water vapor. Therefore, by providing the cooling unit 6, the water vapor in the mixture can be cooled to liquid water, and the water recovery rate in the gas-liquid separation unit 7 can be increased. Therefore, the cooling unit 6 is preferably installed between the hydrogen generating substance storage container 1 and the gas-liquid separation unit 7. As the cooling unit 6, for example, a cooler having a structure in which metal cooling fins are arranged in contact with the pipe can be used. Further, an air cooling fan can be used as the cooling unit 6.

  As shown in FIG. 1, it is preferable to arrange a heat insulating material 4 on at least a part of the outer periphery of the hydrogen generating substance storage container 1. By arranging the heat insulating material 4 as described above, it is possible to prevent the heat in the hydrogen generating substance storage container 1 from being released to the outside of the hydrogen generating substance storage container 1, thereby stabilizing hydrogen generation. Can do. This is because, in the hydrogen production apparatus, hydrogen is generated when the hydrogen generating substance is heated and reacts with water. However, even if the hydrogen generating substance is heated, the heat passes through the outer wall of the hydrogen generating substance storage container 1. If released to the outside, the temperature of the hydrogen generating material does not increase, and the reaction efficiency of hydrogen generation may decrease, or the hydrogen generation reaction may stop and hydrogen generation may not occur. This is because by disposing 4 as described above, it is possible to suppress the release of heat in the hydrogen generating substance storage container 1 to the outside.

  In particular, when the hydrogen generating substance storage container 1 and the water storage container 2 are adjacent to each other in the hydrogen production apparatus, at least the hydrogen generating substance storage container 1 and the water storage container 2 are adjacent to each other via the heat insulating material 4. Thus, it is more preferable to arrange the heat insulating material 4. That is, when the hydrogen generating substance storage container 1 and the water storage container 2 are adjacent to each other and are in contact with each other, the heat in the hydrogen generating substance storage container 1 is easily transferred to the water storage container 2 side. The above-mentioned problem due to the temperature drop in the container 1 may occur more remarkably. However, if the heat insulating material 4 is disposed so that the hydrogen generating material storage container 1 and the water storage container 2 are adjacent to each other via the heat insulating material 4, these problems can be avoided. It is particularly preferable that the heat insulating material 4 is disposed on the entire outer periphery of the hydrogen generating substance storage container 1.

  As a material of the heat insulating material 4 arrange | positioned on the outer periphery of the hydrogen generating substance storage container 1, porous heat insulating materials, such as a polystyrene foam and a polyurethane foam, or the heat insulating material which has a vacuum heat insulation structure etc. are preferable, for example.

  The hydrogen generating substance that can be used in the hydrogen production apparatus of the present invention is not particularly limited as long as it is a substance that reacts with water to generate hydrogen, but metals such as aluminum, silicon, zinc, magnesium, aluminum, silicon, zinc and An alloy mainly composed of one or more metal elements in magnesium can be preferably used. In the case of the above alloy, the elements other than the respective metal elements as the main elements are not particularly limited. Here, the “main body” means that 80% by mass or more, more preferably 90% by mass or more is contained with respect to the entire alloy. Only one of the above exemplified metals and alloys may be used as the hydrogen generating material, or two or more may be used in combination. These hydrogen generating substances are substances that do not easily react with water at room temperature, but are easily exothermic with water when heated. In this specification, normal temperature is a temperature in the range of 20-30 ° C.

  Here, for example, the reaction between aluminum and water is considered to proceed according to any of the following formulas (1) to (3). The calorific value according to the following formula (1) is 419 kJ / mol.

2Al + 6H ₂ O → Al ₂ O ₃ .3H ₂ O + 3H ₂ (1)
2Al + 4H ₂ O → Al ₂ O ₃ .H ₂ O + 3H ₂ (2)
2Al + 3H ₂ O → Al ₂ O ₃ + 3H ₂ (3)

  The size of the hydrogen generating substance is not particularly limited. For example, the average particle size is preferably 0.1 μm or more and 100 μm or less, more preferably 50 μm or less. The hydrogen generating substance generally has a stable oxide film formed on the surface. Therefore, in the case of forms such as a plate shape, a block shape, and a bulk shape having a particle diameter of 1 mm or more, the reaction with water does not proceed even when heated, and hydrogen may not be generated substantially. However, when the average particle size of the hydrogen generating substance is 100 μm or less, the action of suppressing the reaction with water by the oxide film is reduced, and although it is difficult to react with water at room temperature, the reactivity with water increases when heated, and hydrogen The developmental response becomes persistent. Further, when the average particle size of the hydrogen generating material is 50 μm or less, hydrogen can be generated by reacting with water even under mild conditions of about 40 ° C. On the other hand, when the average particle size of the hydrogen generating material is less than 0.1 μm, the ignitability becomes high and handling becomes difficult, or the packing density of the hydrogen generating material decreases and the energy density tends to decrease. . For this reason, it is desirable that the average particle size of the hydrogen generating material be within the above range.

  The average particle diameter as used herein means the value of the particle diameter at a volume-based integrated fraction of 50%. As a method for measuring the average particle diameter, for example, a laser diffraction / scattering method or the like can be used. Specifically, this is a particle diameter distribution measurement method using a scattering intensity distribution detected by irradiating a measurement target substance dispersed in a liquid phase such as water with laser light. As a particle size distribution measuring apparatus by the laser diffraction / scattering method, for example, “Microtrac HRA” (trade name) manufactured by Nikkiso Co., Ltd. can be used.

  Further, the shape of the hydrogen generating substance is not particularly limited, and for example, the average particle diameter may be in the form of particles or flakes within the above range.

  In order to easily start the reaction between water and the hydrogen generating substance, it is preferable to heat at least one of the hydrogen generating substance and water. For example, when water is heated in the water storage container 2, the water temperature increases. The density of water decreases and the weight of the water supplied by the pump 5 decreases, which may cause a decrease in the hydrogen generation rate. Is more preferably heated at a stage after passing through the pump 5. The heating temperature is 40 ° C. or higher, more preferably 60 ° C. or higher, and desirably 100 ° C. or lower. The temperature at which the exothermic reaction between the hydrogen generating substance and water can be maintained is usually 40 ° C. or higher. Once the exothermic reaction starts and hydrogen is generated, the internal pressure of the hydrogen generating substance storage container 1 increases and water is generated. In some cases, the boiling point of the water may rise and the temperature in the container may reach 120 ° C., but the heating temperature is preferably 100 ° C. or less from the viewpoint of controlling the hydrogen generation rate.

  The heating may be performed only at the start of the exothermic reaction. This is because once the exothermic reaction between water and the hydrogen generating substance is started, the subsequent reaction can be continued by the heat of the exothermic reaction. The heating and the supply of water into the hydrogen generating substance storage container 1 may be performed simultaneously.

  Although the heating method is not particularly limited, heating can be performed using heat generated by energizing the resistor. For example, the resistor is attached to the outside of the hydrogen generating substance container 1 or the water container 2 (preferably only the hydrogen generating substance container 1) to generate heat, and these containers are heated from the outside to generate hydrogen. At least one of the substance and water can be heated. The type of the resistor is not particularly limited, and for example, a metal heating element such as a nichrome wire or a platinum wire, silicon carbide, a PTC thermistor, or the like can be used.

  The heating can also be performed by heat generation due to a chemical reaction of the exothermic substance. As this exothermic substance, a substance that becomes an hydroxide or a hydrate by exothermic reaction with water, a substance that generates exothermic reaction with water and hydrogen can be used. Examples of the substance that becomes exothermic reaction with water to become a hydroxide or hydrate include, for example, alkali metal oxides (such as lithium oxide), alkaline earth metal oxides (such as calcium oxide and magnesium oxide), and alkali. An earth metal chloride (such as calcium chloride or magnesium chloride), an alkaline earth metal sulfate compound (such as calcium sulfate), or the like can be used. Examples of substances that generate hydrogen by exothermic reaction with water include alkali metals (such as lithium and sodium), alkali metal hydrides (such as sodium borohydride, potassium borohydride, and lithium hydride). Can do. These substances can be used alone or in combination of two or more.

  The exothermic material is disposed in the hydrogen generating material storage container 1 together with the hydrogen generating material, and water and the exothermic material are reacted exothermically by adding water to the hydrogen generating material, and the hydrogen generating material is contained inside the hydrogen generating material storage container 1. And water can be heated directly. In addition, by arranging the exothermic material outside the hydrogen generating substance storage container 1 and the water storage container 2 (preferably only the hydrogen generating substance storage container 1) to generate heat, and heating these containers from the outside, It is possible to heat at least one of the hydrogen generating material and water.

  As the exothermic substance, a substance that exothermically reacts with a substance other than water, for example, a substance that exothermically reacts with oxygen such as iron powder is also known. Since such a substance needs to introduce oxygen for the exothermic reaction, it is preferable to use it by placing it outside the container rather than putting it in the hydrogen generating substance storage container 1.

  When the heat generating material is stored in the hydrogen generating material containing container 1 together with the hydrogen generating material, and water is supplied to the heat generating material to heat it, the heat generating material is dispersed or mixed with the hydrogen generating material uniformly or non-uniformly. Although it may be used, it is more preferable that the exothermic substance is unevenly arranged in the hydrogen generating substance storage container 1, and the exothermic substance is located in the vicinity A of the water supply pipe 1b inside the hydrogen generating substance storage container 1. It is particularly preferred that the be partially distributed. By unevenly distributing the exothermic material in the hydrogen generating material storage container 1, the time from the start of supplying water to the heating of the hydrogen generating material can be shortened, and rapid hydrogen production is possible. It can be.

  The material and shape of the hydrogen generating substance storage container 1 are not particularly limited as long as the hydrogen generating substance containing container 1 can store a hydrogen generating substance that generates hydrogen by exothermic reaction with water. It is preferable to adopt a material or shape that does not leak hydrogen. As a specific material for the container, a material that hardly permeates water and hydrogen and that does not break even when heated to about 100 ° C. is preferable. For example, a metal such as aluminum or iron, polyethylene (PE), polypropylene ( A resin such as PP) can be used. Further, as the shape of the container, a prismatic shape, a cylindrical shape or the like can be adopted.

  The reaction product produced by the reaction of the hydrogen generating material with water usually has a larger volume than the hydrogen generating material. Therefore, the hydrogen generating substance storage container 1 may be deformable in accordance with the reaction between the hydrogen generating substance and water so as not to be damaged when the volume expansion accompanying the generation of such a reaction product occurs. preferable. From this point of view, the material of the hydrogen generating substance storage container 1 is more preferably a resin such as PE or PP among the materials exemplified above.

  The hydrogen generating substance storage container 1 is provided with a hydrogen deriving unit for deriving hydrogen. The hydrogen lead-out unit is not particularly limited, and may be, for example, a hydrogen lead-out pipe 1a as shown in FIG. 1 or a hydrogen lead-out port. Furthermore, it is preferable to install a filter in the hydrogen lead-out pipe, the hydrogen lead-out port, etc. so that the hydrogen generating substance in the container does not go outside. The filter is not particularly limited as long as it has a characteristic that allows gas to pass but hardly allows liquid and solid to pass through. For example, a PP nonwoven fabric can be used.

  The water storage container 2 has inflexibility and is sealed so that when water is supplied to the hydrogen generating substance storage container 1, the inside thereof is decompressed. That is, when water is supplied from the water storage container 2 to the hydrogen generating substance storage container 1, the gas or liquid for ensuring the pressure reduced from other than the gas-liquid separator 7 does not flow without deformation. If there is, there is no particular limitation. As a material of the water container 2, resin, metal, glass, or the like can be used. Among these, it is preferable to use a resin. By using these materials, it is possible to reliably impart inflexibility to the water container 2.

  When the tank-shaped container shown in FIG. 1 is adopted as the water storage container 2, it is necessary to use a pump 5 or the like to supply water from the water storage container 2 to the hydrogen generating substance storage container 1.

  Furthermore, it is preferable to provide a pressure relief valve in the hydrogen production apparatus. Thereby, for example, even when the hydrogen generation rate increases and the internal pressure of the apparatus rises, the apparatus can be prevented from being damaged due to rupture or the like by discharging hydrogen from the pressure relief valve to the outside of the apparatus. The installation location of the pressure relief valve is not particularly limited as long as the hydrogen generated in the hydrogen generating substance storage container 1 can be discharged. For example, if it is an apparatus of the structure shown in FIG. 1, you may provide a pressure relief valve in any location between the hydrogen outlet pipe 1a and the gas-liquid separation part 7. FIG.

(Embodiment 2)
2 and 3 are partial cross-sectional schematic views showing another example of the hydrogen production apparatus of the present invention. 2 and 3, the same parts as those of the hydrogen production apparatus shown in FIG. 2 and 3, only the hydrogen generating substance storage container 1, the water storage container 2, the heat insulating material 4, and the gas-liquid separation unit 7 are shown in cross section, as in FIG.

  In the hydrogen production apparatus of the present invention, even if the supply of water is stopped during hydrogen generation, hydrogen continues to be generated until the water inside the hydrogen generating substance storage container 1 is reacted or discharged. Therefore, after the supply of water is stopped, a mixture of hydrogen and water is discharged from the hydrogen generating substance storage container 1 and separated into hydrogen and water by the gas-liquid separator 7. However, since the supply of water is stopped, the pressure inside the water storage container 2 does not decrease, water is not recovered from the gas-liquid separator 7, and water is stored in the gas-liquid separator 7. Therefore, in the hydrogen production apparatus of the present embodiment, a new water recovery pipe 7e and a flow path switching valve 8 are provided in the lower part of the gas-liquid separation unit 7. When hydrogen is generated, water is supplied from the water storage container 2 to the hydrogen generation substance storage container 1 using the pump 5 in the state shown in FIG. Thereafter, when the supply of water is stopped to stop the hydrogen generation, the flow path switching valve 8 is set to the state shown in FIG. 3 to connect the water recovery pipe 7e and the water supply pipe 2a. And the pump 5 is made to flow backward and the water stored in the gas-liquid separation part 7 is collect | recovered to the water storage container 2 through the water collection pipe | tube 7e and the water supply pipe 2a. According to the present invention, it is possible to recover the water stored in the gas-liquid separator 7 after stopping the supply of water only by adding the water recovery pipe 7e and the flow path switching valve 8. Thereby, it can prevent that water stores in the gas-liquid separation part 7 after water supply stop, and can prevent that water overflows from the hydrogen discharge pipe 7c.

  In the present embodiment, the first water recovery part is constituted by water recovery pipes 2b and 7d, and the second water recovery part is constituted by a water recovery pipe 7e, a pump 5, and a water supply pipe 2a.

  According to the hydrogen production apparatus of the present invention described in the first embodiment and the second embodiment, the theoretical hydrogen generation amount (in the case of aluminum, for example) when it is assumed that all of the hydrogen generating material has reacted, although it varies depending on conditions. (The theoretical hydrogen generation amount per gram is approximately 1360 ml in terms of 25 ° C.), whereas the actual hydrogen generation amount is approximately 50% or more, more preferably 70% or more, and hydrogen is efficiently generated. It becomes possible to make it.

  Next, the fuel cell of the present invention will be described. The fuel cell of the present invention only needs to include the hydrogen production apparatus of the present invention as a hydrogen supply source, and there are no particular restrictions on other configurations, and various configurations employed in conventional fuel cells can be employed. A portable fuel cell can be obtained.

  When a polymer electrolyte fuel cell is used as the fuel cell and the hydrogen production apparatus has a cooling unit 6 (FIG. 1), the temperature at which the mixture of water and hydrogen is cooled by the cooling unit 6 is constant. It is preferable that the temperature be equal to or higher than the temperature of the fuel cell when operating in a state. In a polymer electrolyte fuel cell, the conductivity of the electrolyte solid polymer decreases when it is dried. For this reason, hydrogen and air, which are fuels, are generally humidified and supplied. Accordingly, in the hydrogen production apparatus, when the mixture of water and hydrogen discharged from the hydrogen generating substance storage container 1 (FIG. 1) is cooled to a low temperature by the cooling unit 6, the humidity in the supplied hydrogen is reduced. The temperature at which the mixture is cooled in the part 6 is preferably close to the operating temperature of the fuel cell.

  Hereinafter, the present invention will be described in detail based on examples. However, the following examples are not intended to limit the present invention, and all modifications made without departing from the spirit of the preceding and following descriptions are included in the technical scope of the present invention.

Example 1
Hydrogen was produced as follows using the hydrogen production apparatus shown in FIG. As the hydrogen generating substance storage container 1, a PP prismatic container having an internal volume of 65 cm ³ was used. Aluminum pipes having an inner diameter of 2 mm and an outer diameter of 3 mm were used for the water supply pipe 1b and the hydrogen outlet pipe 1a. The water container 2 also has the same structure and configuration as the hydrogen generating substance container 1, and the same aluminum pipe as the water supply pipe 1b and the like was used for the water supply pipe 2a and the water recovery pipe 2b. The desorption part 3 has a structure in which the tubes of the hydrogen generating substance storage container 1 and the water storage container 2 are inserted into a cylindrical part having an inner diameter of 3.5 mm on the hydrogen production apparatus side. A circular ring made of resin is arranged in each cylindrical part so that leakage of hydrogen and water from the desorption part 3 is suppressed. In the hydrogen production apparatus, a heat insulating material 4 made of foamed neoprene rubber having a thickness of 5 mm was installed so as to wrap the outer periphery of the hydrogen generating substance storage container 1.

  The cooling unit 6 was configured by arranging a stainless steel tube having an outer diameter of 3 mm and an inner diameter of 2 mm in contact with a 40 × 50 × 12 mm aluminum cooling fin. The cooling fin has eight fins having a thickness of 1 mm, and a stainless steel tube 200 mm is in contact with the cooling fin. The tube length from the desorption part 3 to which the hydrogen lead-out pipe 1a is connected to the gas-liquid separation part 7 was 350 mm.

  First, 21 g of aluminum powder having an average particle diameter of 6 μm as a hydrogen generating substance and 3.5 g of calcium oxide as a heat generating substance are put into the hydrogen generating substance containing container 1, and then the hydrogen generating substance containing container 1 is connected to the hydrogen outlet pipe 1 a and water. It sealed with the lid | cover with the supply pipe | tube 1b. 50 g of water was injected into the water container 2, and the hydrogen generating substance container 1 and the water container 2 were connected to the desorption part 3 as shown in FIG.

  The gas-liquid separation unit 7 has an aluminum water separation container 7a of 20 × 20 × 5 mm attached with an aluminum tube having an inner diameter of 2 mm and an outer diameter of 3 mm as a hydrogen introduction tube 7b, a hydrogen discharge tube 7c, and a water recovery tube 7d. Configured. The gas-liquid separator 7 and the water container 2 were installed at the same height (horizontal position) with respect to the vertical direction.

  Next, water was continuously supplied from the water storage container 2 to the hydrogen generating substance storage container 1 at a water amount of 1.1 g / min using the pump 5.

  Hydrogen was generated immediately after the water was supplied, and the hydrogen generation rate and the surface temperature of the hydrogen generating substance storage container 1 suddenly increased. After about 10 minutes, the hydrogen generation rate and the surface temperature of the hydrogen generating substance storage container 1 became constant, and hydrogen was generated at a constant hydrogen generation rate of about 150 ml / min.

  A mixture of hydrogen and water was discharged from the hydrogen generating substance storage container 1. In the gas-liquid separation part 7, hydrogen and water were separated, hydrogen was discharged from the hydrogen discharge pipe 7c, and water was stored in the lower part of the water separation container 7a. However, the water storage container 2 becomes a volumetric decompression to which water is supplied from the water supply pipe 2a, and the water stored in the water separation container 7a can be sucked by the negative pressure and recovered into the water storage container 2. It was. Although the gas-liquid separation unit 7 was arranged at a position horizontal to the water container 2, the water was constantly collected in the water container 2 without being stored in the gas-liquid separation unit 7.

(Example 2)
Hydrogen was produced in the same procedure as in Example 1 using the hydrogen production apparatus shown in FIGS. In the hydrogen production apparatus of the present embodiment, in the hydrogen production apparatus of the first embodiment, a new water recovery pipe 7e is attached to the gas-liquid separation unit 7, and the pump 5 and the water supply pipe 1b of the hydrogen generating substance storage container 1 are connected. A flow path switching valve 8 was attached between them. The flow path switching valve 8 can switch between a state where the pump 5 and the water supply pipe 1b are in communication (FIG. 2), or a state where the pump 5 and the water recovery pipe 7e are in communication (FIG. 3). Except for the above, an apparatus having the same configuration as the hydrogen production apparatus shown in FIG. 1 was used.

  After continuing to supply water for 1 hour in the state of FIG. 2 to generate hydrogen, the flow path switching valve 8 was switched to the state of FIG. 3 and the pump 5 was made to flow backward. Even after the supply of water was stopped in the state of FIG. 3, the mixture of hydrogen and water flowed into the gas-liquid separator 7. Hydrogen was discharged from the hydrogen discharge pipe 7c, and water was stored in the lower part of the water separation container 7a. The stored water could be recovered from the water recovery pipe 7e to the water storage container 2 through the flow path switching valve 8, the pump 5, and the water supply pipe 2a. After 5 minutes, the pump 5 was stopped because the mixture of hydrogen and water was not discharged.

(Comparative Example 1)
Hydrogen was produced in the same manner as in Example 1 using an apparatus having the same configuration as in FIG. 1 except that a hole communicating with the atmosphere was provided in the upper part of the water container 2. As a result, hydrogen was generated as in Example 1. However, in the apparatus of Comparative Example 1, the inside of the water storage container 2 was not decompressed, and the water stored in the water separation container 7a did not return to the water storage container 2. When hydrogen generation was continued as it was, the water stored in the water separation container 7a overflowed from the hydrogen discharge pipe 7c.

(Reference example)
Using the hydrogen production apparatus of Example 1, hydrogen was generated for 1 hour in the same manner as in Example 1. Thereafter, the pump 5 was stopped. Even after the pump 5 was stopped, the mixture of hydrogen and water flowed into the gas-liquid separator 7. Since the supply of water was stopped, the pressure inside the water storage container 2 did not decrease, and the water stored in the water separation container 7a did not return to the water storage container 2. Three minutes later, the water stored in the water separation container 7a overflowed from the hydrogen discharge pipe 7c.

  As described above, according to the present invention, it is possible to provide a hydrogen production apparatus capable of producing hydrogen simply and efficiently, and a fuel cell using the hydrogen production apparatus as a hydrogen supply source.

It is a partial section schematic diagram showing an example of the hydrogen production device of the present invention. It is a partial cross section schematic diagram which shows another example of the hydrogen production apparatus of this invention. It is a partial cross section schematic diagram which shows another example of the hydrogen production apparatus of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Hydrogen generating substance storage container 10 Hydrogen generating substance 1a Hydrogen outlet pipe 1b Water supply pipe 2 Water storage container 20 Water 2a Water supply pipe 2b Water recovery pipe 3 Desorption part 4 Thermal insulation material 5 Pump 6 Cooling part 7 Gas-liquid separation part 7a Water Separation vessel 7b Hydrogen introduction pipe 7c Hydrogen discharge pipe 7d, 7e Water recovery pipe 8 Flow path switching valve

Claims (10)

A hydrogen generating substance storage container for storing a hydrogen generating substance;
A water container for containing water;
A water supply unit for supplying water from the water container to the hydrogen generating substance container;
A hydrogen lead-out part for leading out hydrogen from the hydrogen generating substance storage container;
A gas-liquid separation unit for separating water from a mixture containing hydrogen and water discharged from the hydrogen generating substance storage container;
A hydrogen production device including a water recovery unit for recovering water separated in the gas-liquid separation unit in the water storage container,
The water storage container has inflexibility and is sealed so that the inside of the water storage container is depressurized when water is supplied to the hydrogen generating substance storage container.
The said water collection | recovery part attracts | sucks water from the said gas-liquid separation part, and collects water to the said water storage container, when the said water storage container is pressure-reduced, The hydrogen production apparatus characterized by the above-mentioned. The water recovery unit includes a first water recovery unit and a second water recovery unit,
The first water recovery unit sucks water from the gas-liquid separation unit when the water storage container is depressurized, and recovers water to the water storage container.
2. The hydrogen production apparatus according to claim 1, wherein the second water recovery unit sucks water from the gas-liquid separation unit and recovers water to the water storage container when the water storage container is in a non-depressurized state.   The hydrogen production apparatus according to claim 2, wherein the second water recovery unit includes a pump and a flow path switching unit.   The said water container is a hydrogen production apparatus in any one of Claims 1-3 which are not provided with opening parts other than the opening part to which the said water supply part and the said water collection | recovery part are connected, respectively.   The cooling part for cooling the said mixture before the mixture containing the hydrogen and water discharged | emitted from the said hydrogen generating substance storage container enters the said gas-liquid separation part is further included in any one of Claims 1-4. Hydrogen production equipment.   The said water collection | recovery part is a hydrogen production apparatus in any one of Claims 1-5 arrange | positioned below the said gas-liquid separation part with respect to the perpendicular direction. The hydrogen generating substance storage container stores a hydrogen generating substance,
The hydrogen generating material is at least one metal selected from the group consisting of aluminum, silicon, zinc, magnesium, and an alloy mainly composed of one or more of these metal elements. The hydrogen production apparatus as described.   The hydrogen production apparatus according to claim 7, wherein the hydrogen generating substance storage container further stores a heat generating substance that reacts exothermically with water.   The hydrogen generating apparatus according to claim 8, wherein the exothermic substance is unevenly distributed in the vicinity of the opening of the water supply unit.   A fuel cell comprising the hydrogen production apparatus according to claim 1 as a hydrogen supply source.

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