JP6121839B2 - Oxygen reduction device - Google Patents

Description

  Embodiments described herein relate generally to an oxygen reduction device.

  Conventionally, the CA (Controlled Atmosphere) storage method includes a gas replacement method that is widely used in the food industry, a vacuum method that reduces oxygen by reducing the pressure, and a polymer electrolyte membrane that reduces oxygen in the CA storage room. For example, a polymer electrolyte method, an adsorption method using an oxygen adsorbent, and the like.

  The gas replacement method is a method in which a gas typified by nitrogen or carbon dioxide gas is stored by being replaced with air, and is widely used for maintaining freshness in the distribution process of food and vegetables.

  The vacuum method is a method of depressurizing as a method of reducing oxygen in order to prevent oxidation of food. Since the performance correlates with the degree of vacuum, the strength of the storage container and the capacity of the vacuum pump are required, which makes the apparatus relatively large.

  The method using an oxygen adsorbent is also widely used in the distribution process of confectionery and the like as in the gas replacement method. However, if the adsorbent breaks through adsorption, the effect is lost and the life is short.

  In the polymer electrolyte membrane method, hydrogen ions are electrolyzed at the anode to form hydrogen ions, the hydrogen ions move through the polymer electrolyte membrane and reach the cathode, and react with oxygen in the oxygen reduction chamber to produce water. By consuming oxygen. Therefore, there is a merit that the pressure change is small and the strength of the oxygen-reducing chamber is not necessary.

JP 2004-218924 A Japanese Patent Laid-Open No. 9-287869 JP-A-6-184237

  However, in the polymer electrolyte membrane method, if the water supplied to the anode contains impurities, ion contaminant components in the water cause a reaction in the polymer electrolyte membrane, degrading the performance of the polymer electrolyte membrane. . Therefore, the water needs to be pure water or ion exchange water. For example, there is a problem that tap water must be supplied after ion exchange.

  In addition, in order for the user to replenish water in the tank of the oxygen reduction device, this tank needs to be installed in a place where it can be easily replenished, and there is a problem that this is a limitation on the design of the oxygen reduction device.

  Then, in view of the said problem, embodiment of this invention aims at providing the oxygen reduction apparatus which can supply the pure water without an ion contamination component, without a user supplying water.

An oxygen reduction device according to an embodiment of the present invention includes a polymer electrolyte membrane, an anode provided on one side of the polymer electrolyte membrane, and provided on the other side of the polymer electrolyte membrane, to the oxygen reduction chamber. An oxygen-reducing cell comprising: a cathode that communicates with the anode; an anode current collector that energizes the anode; and a cathode current collector that energizes the cathode; and a powder that is provided on the anode side and supplies water to the anode or possess a water supply comprising a particle of the water-absorbing agent, wherein the water absorbing agent of the water supply member is carrying the carrier, the contains metal carrier, a reduced oxygen apparatus.

The expanded longitudinal section of the oxygen reducing device of the embodiment of the present invention. The exploded perspective view of a hypoxic cell. The perspective view of a water supply body. The enlarged partial view seen from the front of a water supply body. FIG. 2 is a sectional view taken along line AA in FIG. 1. The graph showing the amount of water absorption of a silica gel.

  Hereinafter, the oxygen reduction apparatus 10 of one Embodiment is demonstrated based on FIGS. The oxygen reduction device 10 of this embodiment has an oxygen reduction chamber 12 and an oxygen reduction cell 14 using a polymer electrolyte membrane method. As an example of use of the oxygen reduction device 10 of the present embodiment, for example, an oxygen reduction chamber 12 is provided in a food storage room or a household refrigerator, and the oxygen reduction device 10 for reducing oxygen inside the oxygen reduction chamber 12 is used. Use.

  The oxygen reduction device 10 will be described with reference to FIGS. 1 and 2. FIG. 1 is a longitudinal sectional view of the oxygen reduction device 10, and FIG. 2 is an exploded perspective view of the oxygen reduction cell 14. In FIGS. 1 and 2, the thickness of each member is thin, but the thickness is enlarged for easy understanding.

  A polymer electrolyte membrane (hereinafter simply referred to as “electrolyte membrane”) 16 is provided in the vertical direction, an anode 18 is provided at the rear of the electrolyte membrane 16, and a cathode 20 is provided at the front of the electrolyte membrane 16. . The cathode 20 is a laminate of a carbon catalyst and carbon paper. The anode 18 and the cathode 20 each carry a platinum catalyst. The electrolyte membrane 16, the anode 18, and the cathode 20 are integrally joined using a hot press or the like. An anode current collector 22 is provided behind the anode 18, and a cathode current collector 24 is provided in front of the cathode 20. Both current collectors 22 and 24 are mesh-like titanium films whose surfaces are plated with platinum. The anode current collector 22 applies positive current to the anode 18, and the cathode current collector 24 applies negative current to the cathode 20. Do. Both current collectors 22 and 24 are energized from electric wires 26 and 28. In addition, an insulator 30 is provided between the current collectors 22 and 24 so that the current collectors 22 and 24 do not contact each other. The insulator 30 has a frame shape, and the electrolyte membrane 16, the anode 18, and the cathode 20 are accommodated therein.

  The oxygen reduction cells 14 stacked in order as described above are sandwiched between a pair of front and rear fixing members 32 and 34 and fixed with screws 50.

  First, as shown in FIG. 2, the fixing member 32 attached to the cathode 20 side has a rectangular parallelepiped shape, and a plurality of slit-like air holes 36 are opened in the vertical direction. As shown in FIG. 1, the oxygen reduction cell 14 is attached to the rear side of the fixing member 32, and the oxygen reduction chamber 12 is attached to the front side. As shown in FIG. 1, an opening 38 that leads to the vent hole 36 is opened on the rear surface of the oxygen reduction chamber 12.

  Next, the fixing member 34 attached to the anode 18 side will be described. The fixing member 34 has a box shape, and a storage chamber 43 is provided therein. A plurality of lateral ventilation holes 40 are opened on the front surface of the fixing member 34, the rear surface is opened, and the rear surface is detachable. A plate-like lid 42 is attached. A plurality of vent holes 44 extending in the vertical direction are opened on both side surfaces of the fixing member 34.

  A plate-shaped heater 46 is disposed in front of the bottom of the storage chamber 43 in the fixing member 34, and a rectangular water supply body 48 is placed on the bottom so as to be in contact with the heater 46. The water supply body 48 will be described in detail later.

  The oxygen reduction chamber 12, the fixing member 32, the oxygen reduction cell 14, and the box-type fixing member 34 are fixed to each other by a plurality of screws 50.

  Next, the structure of the water supply body 48 is demonstrated based on FIGS.

  As shown in FIG. 3, the water supply body 48 has a rectangular parallelepiped structure in which a sheet-like liner 52, a center core 54, and a liner 52 are laminated in order as in the case of corrugated cardboard. As shown in the enlarged view of FIG. 4, a sheet-shaped core 54 formed in a corrugated cross section is sandwiched and fixed between two sheet-shaped liners 52, 52.

  As shown in FIG. 4, the core 54 has a three-layer structure, and both sides of a metal foil (for example, an aluminum foil) 56 are laminated with paper 58 and 58. A powder or granular water-absorbing agent 64 is supported on the entire surface of the papers 58 and 58 on both sides of the core 54. As the water absorbing agent 64, for example, powdery A-type silica gel is used. As this supporting method, for example, paste is applied to the entire surface of the paper 58, 58 of the core 54, and a powder or granular water-absorbing agent 64 is sprayed on the entire surface.

  As shown in FIG. 4, the liner 52 similarly has a three-layer structure, and both sides of the metal foil 60 are laminated with paper 62 and 62. The water absorbing agent 64 in the form of powder or granules is also carried on the entire surface of the papers 62 and 62 on both sides of the liner 52. As shown in FIG. 3, as a carrying method, for example, paste is applied to the entire surface of the paper 62, 62 of the liner 52, and a water-absorbing agent 64 of powder or granules is sprayed on the entire surface.

  Thereby, in this embodiment, the liner 52 and the inner core 54 of the water supply body 48 serve as a carrier for the water-absorbing agent 64 in the form of powder or granules. As shown in FIGS. 1 and 2, the rectangular water supply 48 formed in this way is placed on the bottom of the storage chamber 43 in the fixing member 34, and the vent holes 44 are formed on both sides of the placement. , 44. And as shown in FIG. 1, after installing the water supply body 48, the lid | cover 62 is attached.

  Next, the operation state of the oxygen reduction device 10 will be described. As shown in FIGS. 1 and 5, water vapor is supplied from the water supply body 48 to the anode 18 through the vent hole 40. On the other hand, as shown in FIG. 1, the air in the oxygen reduction chamber 102 is supplied to the oxygen reduction cell 14 through the opening 38 and the vent hole 36 of the fixing member 32, and both the current collectors 22 and 24 are energized. Therefore, oxygen is reduced from the inflowing air, and oxygen in the oxygen reduction chamber 102 is reduced. The anode 18 and the cathode 20 perform the oxygen reduction reaction as in the following formulas (1) and (2).

Anode: 2H ₂ O → O ₂ + 4H ⁺ + 4e ⁻ (1)

Cathode ... O ₂ + 4H ⁺ + 4e ⁻ → 2H ₂ O (2)

Explaining the oxygen reduction reaction formulas of the formulas (1) and (2), water vapor is supplied from the water supply body 48 and electrolyzed at the anode 18 to form protons (hydrogen ions). To reach the cathode 20 and react with oxygen in the oxygen reduction chamber 12 to generate water and consume oxygen. Thereby, oxygen reduction is performed inside the oxygen reduction chamber 12.

  Next, how the water supply body 48 supplies water vapor will be described with reference to FIGS. Air flows from the vent hole 44 on one side of the fixing member 34 and passes through the air flow passage 66 inside the water supply body 48. At this time, the water absorbent 64 absorbs water from the air and releases water. Do. Then, the air flows out from the vent hole 44 on the other side surface of the fixing member 34. On the other hand, water vapor flows upward from both sides of the water supply body 48, reaches the anode 18 from the vent hole 40, and supplies water vapor.

  As described above, the water-absorbing agent 64 made of powdered A-type silica gel absorbs and releases moisture in the air. At this time, the water-absorbing agent 64 can discharge pure water free from ion contamination components in order to supply water from moisture in the air.

  The reason why the powder or granular water-absorbing agent 64 is used is that the larger the surface area, the faster the water absorption amount and the water absorption speed. As shown in the graph of FIG. 6, when the diameter of the water absorbing agent 64 is 5 to 10 mm, the water absorption amount is 10 wt% in 2 hours and 16 wt% in 5 hours. On the other hand, when the silica gel is a powder having a smaller diameter (particle diameter is several hundreds μm to 1 mm), the water absorption is 18 wt% in 2 hours and 34 wt% in 5 hours, which is almost twice as much. .

  Further, as shown in FIG. 3, by supporting the water-absorbing agent 64 on a sheet-like carrier such as the liner 52 and the core 54, the water supply body 48 is formed in a free shape according to the portion to be stored. be able to. Therefore, the water supply body 48 is not limited to a rectangular parallelepiped, and can be formed in other shapes.

  Further, as shown in FIG. 3, since a powder or granular water-absorbing agent 64 is supported on the entire surface of the sheet-like carrier, the surface area can be increased, air can be circulated, and water can be absorbed. And can promote release.

  As shown in FIGS. 3 and 4, in this embodiment, a flow passage 66 through which air flows is formed between the liner 52 and the corrugated core 54 like a cardboard base paper. Thereby, air enters the inside of the water supply body 48, and the entire water-absorbing agent 64 carried on the entire surface of the liner 52 and the core 54 can be used effectively.

  Further, as shown in FIG. 4, since the liner 52 and the center core 54 have metal foils 56 and 60 incorporated therein, the heat supply of the oxygen-reducing cell 14 and the heat from the heater 46 are supplied to the entire water supply body 48. It is easy to convey to water, and the discharge of water from the water supply body 48 can be further promoted.

  In addition, since the liner 52 has a three-layer structure of paper 58 and metal foil 56 and the core 54 has a three-layer structure of paper 62 and metal foil 60, the liner 52 and the core 54 are formed by the sheet-like metal foils 56 and 60. Heat can be transferred to the whole, and the metal foils 56 and 60 are not exposed on the surface, so that the process of supporting the water absorbing agent 64 is simplified.

  Since powdery A-type silica gel is used as the water-absorbing agent 64, the material is inexpensive, moisture can be released at a low temperature, and energy used at the time of release can be reduced. A type silica gel is standardized by JIS.

  According to the present embodiment, pure water without ion contact can be supplied to the anode 18 side of the oxygen reduction apparatus 10, and the user does not need to supply water to a tank or the like.

  Moreover, since the water supply body 48 can be formed in various shapes, there is no design limitation when the oxygen-reducing cell 14 is formed.

  Moreover, since it is the water absorbing agent 64 of a powder or a granule, water absorption can be accelerated | stimulated more.

  In addition, since the powder or granular water-absorbing agent 64 is simply carried on the sheet-like carrier (the liner 52 and the core 54), the water supply body 48 can be easily formed.

  Further, since the powdery or granular water-absorbing agent 64 is supported on the sheet-like carrier (liner 52, inner core 54), the surface area can be increased, air can be more circulated, Release can be accelerated.

  In addition, since the water supply body 48 has a shape in which the liner 52 and the core 54 are laminated, an air flow passage 66 can be formed, so that air enters the water supply body 48, and the entire surface of the liner 52 and the core 54 is supported. The entire water-absorbing agent 64 held can be used effectively.

  Moreover, since the metal foil 56 and the metal foil 60 are contained in the sheet-like carrier (the liner 52 and the core 54), heat can be easily transmitted to the entire water supply body 48.

  In addition, since the sheet-like metal foil 56 and the metal foil 60 are built in the liner 52 and the core 54, heat can be uniformly transferred to the entire liner 52 and the core 54.

  Further, since A-type silica gel is used as the water-absorbing agent 64, the material itself is inexpensive, moisture can be released at a low temperature, and energy used at the time of release can be reduced.

  In the above embodiment, the vent hole 40 is provided above the air supply body 48 in the direction orthogonal to the air flow. However, the present invention is not limited to this, and the anode 18 of the oxygen reduction cell 14 may be provided in the direction in which the air flows. This makes it easier for water vapor to reach the anode 18.

  In the above embodiment, the water absorbing agent 64 is formed of silica gel. However, the present invention is not limited to this, and zeolite may be used. In addition, when water such as calcium chloride is included, an irreversible one that maintains the state is not suitable.

  Moreover, in the said embodiment, although the water absorbing agent 64 was carry | supported on the paper 58 and the paper 62, you may carry | support not only to this but a nonwoven fabric, a ceramic porous body, a mesh-like metal, etc.

  Further, when the heat removal from the oxygen reduction cell 14 is sufficient, it is not necessary to provide the heater 46 for heating the water supply body 48.

DESCRIPTION OF SYMBOLS 10 ... Hypoxic device, 12 ... Hypoxic chamber, 14 ... Hypoxic cell, 16 ... Electrolyte membrane, 18 ... Anode, 20 ... Cathode, 22 ... Anode collector Body, 24 ... cathode current collector, 30 ... insulator, 32 ... fixing member, 34 ... fixing member, 46 ... heater, 48 ... water supply body, 52 ... liner , 54 ... middle core, 56 ... metal foil, 58 ... paper, 60 ... metal foil, 62 ... paper, 64 ... water-absorbing agent, 66 ... flow passage

Claims (9)

A polymer electrolyte membrane;
An anode provided on one side of the polymer electrolyte membrane;
A cathode provided on the other side of the polymer electrolyte membrane and leading to a hypoxic chamber;
An anode current collector for energizing the anode;
A cathode current collector for energizing the cathode;
A hypoxic cell having:
A water supply body that is provided on the anode side and includes a water-absorbing agent of powder or granules for supplying water to the anode;
I have a,
The water-absorbing agent of the water supply body is carried on a carrier,
The carrier contains metal,
Hypoxic device. A plurality of the carriers are combined to form an air flow path between the carriers.
The oxygen reduction device according to claim 1 . The oxygen reduction cell is provided in the direction of air flowing out of the flow passage.
The oxygen-reducing device according to claim 2 . The sheet-like carrier includes a metal foil,
The oxygen reduction device according to claim 1 . The water-absorbing agent is silica gel;
The oxygen reduction device according to any one of claims 1 to 4 . The carrier is in sheet form, and the water supply body is carried on both sides of the carrier.
The oxygen reduction device according to claim 1 . The water supply body is laminated with the sheet-like carrier.
The oxygen reduction device according to claim 1 . An air flow path is formed between the stacked sheet-like carriers.
The oxygen reduction device according to claim 7 . The carrier is paper;
The oxygen reduction device according to claim 6 .

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