Flammable gas collection apparatus

Abstract

To provide a flammable gas collection apparatus with excellent safety, which can improve the utility value of a flammable gas.SOLUTION: A flammable gas collection apparatus includes collection chambers for collecting a flammable gas generated in a liquid. The collection chamber is submerged in the liquid. The flammable gas is, for example, hydrogen generated from the surface of an electrode immersed in an electrolyte. The collection chamber should be a pair of collection chambers arranged on one surface side of the electrode and the other surface side facing the one surface side. Occlusion materials should be arranged between the collection chamber and the electrode, and between the electrodes.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a combustible gas recovery device. [Background technology]

[0002] In recent years, from the viewpoint of environmental conservation and energy conservation, efforts have been focused on the effective utilization of flammable gases such as hydrogen and methane gas generated in industrial activities as resources for fuel, etc. For example, there is a known attempt to recover and utilize hydrogen, a flammable gas generated from electrodes during the anodizing of aluminum (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2023-57600 Summary of the Invention [Problem to be solved by the invention]

[0004] The technology disclosed in Patent Document 1 adjusts the pressure of the inert gas so as to maintain a positive pressure relative to atmospheric pressure inside a recovery chamber that recovers the flammable gas. However, this technology leaves room for improvement in terms of safety, as there is a possibility that air may flow into the recovery chamber if the recovery chamber is damaged. In addition to the above, there is also the problem that the configuration for adjusting the pressure of the inert gas is costly, and that the inert gas may be mixed into the recovered flammable gas, causing a decrease (fluctuation) in the concentration of the recovered flammable gas, thereby reducing its utility value.

[0005] The present disclosure has been made in view of the above, and aims to provide a flammable gas recovery device that is highly safe and can improve the utility value of recovered flammable gas. [Means for solving the problem]

[0006] The present disclosure relates to a flammable gas recovery device having a recovery chamber that recovers flammable gas generated from a liquid, the recovery chamber being immersed in the liquid. [Brief explanation of the drawings]

[0007] [Figure 1] 1 is a diagram showing an overview of a flammable gas recovery device according to a first embodiment. [Figure 2] 1 is an exploded perspective view of a flammable gas recovery device according to a first embodiment. FIG. [Figure 3] FIG. 2 is a side view of the recovery chamber of the flammable gas recovery device according to the first embodiment. [Figure 4] FIG. 10 is a diagram showing an outline of a flammable gas recovery device according to a second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0008] (First embodiment) <Combustible gas recovery device> The hydrogen recovery device 1 as a combustible gas recovery device according to this embodiment is a device that recovers hydrogen gas as a combustible gas generated from an electrolytic cell 10 as a combustible gas generation source. In this specification, "combustible gas" refers not only to the hydrogen gas exemplified above, but also to all gases that have an explosive range (combustible range) when mixed with air. Hereinafter, the combustible gas recovery device will be described as the hydrogen recovery device 1 that recovers hydrogen as a combustible gas. However, the combustible gas may be a combustible gas other than hydrogen.

[0009] [Electrolytic cell] The electrolytic bath 10 serving as a source of flammable gas is, for example, an electrolytic bath used in anodizing treatment of a metal material such as aluminum as a treatment target. Hereinafter, the source of generating hydrogen as a flammable gas will be described as the electrolytic bath 10 used in the anodic oxidation treatment. On the other hand, the source of flammable gas is not limited to the electrolytic bath 10, and may be a flammable gas other than hydrogen, such as a methane fermentation bath that generates methane gas. In addition to the electrolytic bath, the source of generating hydrogen as a flammable gas may also be, for example, an etching bath that etches the surface of the treatment target to generate hydrogen.

[0010] As shown in FIG. 1, the electrolytic cell 10 is a tank in which an electrolytic solution 11 is stored, and one or more cathodes 12 are immersed in the electrolytic solution 11. An aluminum material (not shown) to be treated and serving as an anode, and a cathode 12 serving as a counter electrode, are immersed in the electrolytic solution 11 stored in the electrolytic cell 10. By passing a current through the electrolytic cell 10 in this state, an anodized film (anodized aluminum film) is formed on the surface of the aluminum material, and hydrogen is generated from the surface of the cathode 12. As the electrolytic solution 11, for example, an aqueous solution containing sulfuric acid is provided. The hydrogen generated by the anodization process flows into a recovery chamber 20. The configuration of the recovery chamber 20 will be described in detail later.

[0011] In this embodiment, the cathodes 12 are arranged in a row as shown in FIG. 1 . The cathodes 12 may be arranged in multiple rows in one electrolytic cell 10, sandwiching the aluminum material to be treated. The total number of cathodes 12 and the number per row are not particularly limited. The cathodes 12 are held in the electrolytic cell 10 by cathode square tubes. The cathode square tubes are rectangular cylindrical members made of a conductive material, and provide a current path from a power source (not shown) to the multiple cathodes 12. The cathodes 12 are preferably, but not limited to, electrodes made of aluminum or platinum.

[0012] [Hydrogen recovery equipment] 1, the hydrogen recovery device 1 has a recovery chamber 20 that recovers hydrogen gas. In addition to the above, the hydrogen recovery device 1 may also have an inert gas tank 30, a drain bottle 40, a scrubbing tower 50, a blower 60, and a control valve 70. The above components are connected by flow paths L1 to L5.

[0013] (Recovery Room) The recovery chamber 20 has an internal space that is open downward, and recovers hydrogen that flows into the internal space. The recovery chamber 20 is immersed in the electrolytic solution 11. The recovery chamber 20 is preferably disposed below the liquid level F of the electrolytic solution 11 in the electrolytic cell 10. In other words, the entire recovery chamber 20 is preferably immersed in the electrolytic solution 11. This reliably prevents air from flowing into the recovery chamber from the outside.

[0014] FIG. 2 is an enlarged view of the vicinity of the right end of the cathode 12 arranged in a row in FIG. 1 , and is an exploded perspective view showing the configuration of the recovery chamber 20. As shown in FIGS. 1 and 2 , the recovery chamber 20 is preferably a pair of recovery chambers (a recovery chamber 21 arranged on the front side in the Z direction in FIG. 2 and a recovery chamber 22 arranged on the rear side in the Z direction) arranged on one side of the cathode 12 and the other side of the cathode 12, respectively. This allows hydrogen generated from one side and the other side of the cathode 12 to be efficiently recovered. When a plurality of cathodes 12 are arranged in a row as shown in FIGS. 1 and 2 , the recovery chambers 21 and 22 may be a common recovery chamber for each row of cathodes 12. In this case, the longitudinal lengths of the recovery chambers 21 and 22 are preferably configured to be slightly longer than the row length of one row of cathodes 12. That is, the recovery chambers 21 and 22 are preferably configured so that the longitudinal ends of the recovery chambers 21 and 22 extend outward beyond the end in the column direction (X direction in FIG. 2) of one column of cathodes 12. This makes it possible to recover hydrogen generated from the end in the column direction of the cathodes 12, thereby improving the hydrogen recovery efficiency.

[0015] 2, the recovery chamber 21 has a plate-shaped member 21a, a box body 21b, and a connection port 21c. The plate-shaped member 21a has holes h1 which are a plurality of bolt holes that communicate in the thickness direction. One surface of the plate-shaped member 21a is disposed so as to face the cathode 12. The box body 21b is disposed in contact with the other surface of the plate-shaped member 21a.

[0016] The box body 21b has a substantially rectangular parallelepiped shape and has an internal space. As shown in FIG. 3, the box body 21b opens downward (toward the Y direction in FIGS. 2 and 3). It is preferable that the space other than the lower part of the internal space of the box body 21b is enclosed by a surface material or the like to form a closed space. This makes it possible to collect hydrogen that has flowed into the internal space of the box body 21b from below. The surface of the box body 21b that abuts against the plate-like member 21a may not require the placement of a surface material or the like.

[0017] The material for forming the plate-like member 21a and the box body 21b is not particularly limited as long as it is a material that is not corroded by the electrolyte, but it can be made of a resin material such as vinyl chloride, acrylic, or polycarbonate, for example.

[0018] The connection port 21c is connected to a flow path L2 through which hydrogen recovered in the recovery chamber 21 flows out to the outside. The connection port 21c is a cylindrical member. As shown in FIG. 3, the connection port 21c is arranged so as to communicate with a hole h2 formed in a part of the box body 21b. In this embodiment, the connection port 21c is arranged on the upper part of the box body 21b so as to communicate with the hole h2 formed in the upper surface of the box body 21b. The connection port 21c can be configured according to the shape of the flow path to be connected, and for example, a water faucet socket can be used as the connection port 21c. In addition to the connection port 21c, a separate connection port may be provided to connect the flow path L1 in FIG. 1 to the recovery chamber. The configuration of the connection port is, for example, the same as that of the connection port 21c.

[0019] As shown in FIG. 2, the recovery chamber 22 has a plate-shaped member 22a and a box body 22b. The above configuration is the same as that of the plate-shaped member 21a and the box body 21b. The recovery chamber 22 may be provided with a connection port similar to the connection port 21c. The recovery chamber 21 and the recovery chamber 22 are arranged symmetrically with respect to the cathode 12. The hole h1 of the plate-shaped member 21a and the hole h1 of the plate-shaped member 22a are arranged to communicate with each other. A fastener such as a bolt is inserted into the communicating hole h1 to fasten them together. This fixes the recovery chamber 21 and the recovery chamber 22 together.

[0020] The recovery chamber 21 and the recovery chamber 22 may be connected by a flow path 25. This allows the recovery chamber 21 and the recovery chamber 22 to share connection ports such as the connection port 21c, and the inert gas tank 30 and the blower 60 connected to the connection ports, making it possible to form a single piece of equipment. This allows the equipment costs of the hydrogen recovery device 1 to be reduced.

[0021] (Occluder) As shown in Fig. 2, a blocking material 23a is disposed between the recovery chamber 21 and the cathode 12. Similarly, a blocking material 23b is disposed between the cathode 12 and the recovery chamber 22. A blocking material 24 is disposed between adjacent cathodes 12. The blocking materials 23a and 23b can block the spaces between the cathode 12 and the recovery chamber 21 and between the cathode 12 and the recovery chamber 22. The blocking material 24 can block the spaces between adjacent cathodes 12. Therefore, the generated hydrogen can be prevented from escaping from the above-mentioned spaces, thereby improving the hydrogen recovery efficiency.

[0022] The blocking members 23a, 23b preferably have a sheet-like shape and are arranged so that their surfaces abut against the cathode 12-side surfaces of the plate-like members 21a, 22a. The longitudinal length (length in the X direction in FIG. 2) and height length (length in the Y direction in FIG. 2) of the blocking members 23a, 23b may be approximately the same as those of the plate-like members 21a, 22a. This makes it possible to prevent hydrogen from accumulating below the blocking members 23a, 23b.

[0023] The blocking members 23a and 23b are preferably made of a material that has elasticity (resilience) and is not corroded by the electrolyte. Examples of such materials include elastomers and rubber. Among them, chloroprene rubber (CR), nitrile rubber (NBR), or ethylene propylene rubber (EPDM) are preferably used, and ethylene propylene rubber (EPDM) is more preferably used. The blocking members 23a and 23b preferably have an Asker hardness of 8 to 50, and more preferably an Asker hardness of about 15 to 25. The Asker hardness can be measured using a commercially available Asker hardness tester.

[0024] The blocking members 23a, 23b may or may not be bonded to the plate-like members 21a, 22a with an adhesive or the like. A method of fixing the blocking members 23a, 23b without using an adhesive or the like is as follows. For example, when the recovery chamber 21 and the recovery chamber 22 are fixed together, the blocking member 23a is disposed between the recovery chamber 21 and the cathode 12, and the blocking member 23b is disposed between the cathode 12 and the recovery chamber 22. At this time, holes that communicate with the hole h1 are formed in the blocking members 23a, 23b. Then, fasteners such as bolts are inserted into the holes h1, and the fasteners are fastened in a state in which the blocking members 23a, 23b are sandwiched between the recovery chambers 21, 22 and the cathode 12. This allows the blocking members 23a, 23b to be fixed.

[0025] The plugging member 24 can be made of the same material as the plugging members 23a and 23b. The plugging member 24 is larger in size than the gap between the adjacent cathodes 12. For example, the plugging member 24 may be slightly larger in size in the Z direction in FIG. 2 than the above-mentioned substantially rectangular gap, and may be, for example, 1.5 to several times larger in size in the X direction. The plugging member 24 having the above-mentioned shape is deformed into a V-shape when viewed from the Z direction in FIG. 2 and is pressed into and fixed in the gap between the adjacent cathodes 12. The shape into which the plugging member 24 is deformed is not limited to a V-shape, and may be any bent shape that generates a restoring force. For example, the plugging member 24 may be a U-shape or a W-shape or other shape with multiple bends. The plugging member 24 preferably has an Asker hardness of 15 to 25 in order to generate a restoring force. The plugging member 24 is preferably made of a material that is resistant to deterioration over time even when subjected to continuous stress and to deterioration in a strong acid aqueous solution. As the blocking material 24, it is preferable to use chloroprene rubber (CR), nitrile rubber (NBR), or ethylene propylene rubber (EPDM), and it is more preferable to use ethylene propylene rubber (EPDM).

[0026] The plugging material 24 is fixed after the recovery chambers 21, 22 and the plugging materials 23a, 23b are fixed. In Fig. 2, the plugging material 24 is shown as being pushed into the gap between adjacent cathodes 12 from above, but this is not limited to this. The plugging material 24 may be pushed into the gap between adjacent cathodes 12 from below, or may be pushed into the gap from both above and below.

[0027] The plugging members 23a, 23b, and 24 have a preferable elastic force. Therefore, even if the gap between adjacent cathodes 12 or the gap between the cathode 12 and the recovery chambers 21, 22 increases due to deterioration (dissolution) of the cathode 12 over time and thinning of the cathode 12, for example, the plugging members 23a, 23b, and 24 can follow the change in the size of the gap. Therefore, a decrease in the hydrogen recovery rate due to deterioration of the cathode 12 over time can be suppressed.

[0028] In addition to the clogging members 23a, 23b and the clogging member 24, clogging members may be separately disposed at both ends of the cathodes 12 arranged in a row.

[0029] The inert gas tank 30 is connected to the recovery chamber 20 via a flow path L1. An inert gas is supplied from the inert gas tank 30 to the recovery chamber 20. The inert gas is supplied into the recovery chamber 20 before use of the electrolytic cell 10 to replace the air remaining inside the recovery chamber 20 with the inert gas. This prevents the hydrogen recovered in the recovery chamber 20 from mixing with the air, thereby improving the safety of the equipment. In this specification, an inert gas refers to a gas that is chemically stable and significantly less reactive than oxygen. Specific examples of inert gases include nitrogen, carbon dioxide, helium, neon, argon, krypton, and xenon. In this embodiment, nitrogen is used as the inert gas. A valve, a flow meter, or the like capable of adjusting the gas flow rate may be provided in the flow path L1.

[0030] The drain bottle 40 is connected to the recovery chamber 20 via a flow path L2. The drain bottle 40 is configured to remove moisture from the hydrogen recovered by the recovery chamber 20. Instead of the drain bottle 40, a dehumidifier, an electronic cooler, or the like may be used.

[0031] The scrubbing tower 50 is connected to the drain bottle 40 via a flow path L3. The scrubbing tower 50 is a device that removes mist and the like that is scattered when gas bubbles generated in the electrolyte burst on the liquid surface by a cleaning process. The configuration of the scrubbing tower 50 can be a known configuration of a scrubbing tower.

[0032] The blower 60 serving as a suction unit is connected to the scrubbing tower 50 via a flow path L4. The blower 60 sucks in the hydrogen that has flowed into the recovery chamber 20. In this embodiment, the amount of hydrogen sucked by the blower is constant.

[0033] The regulator valve 70, which serves as an adjustment unit, is connected to the blower 60 via a flow path L5. The regulator valve 70 has a flow rate control function and can adjust the flow rate of hydrogen sent to a downstream stage to a predetermined value. The regulator valve 70 can be configured in a known manner.

[0034] In this embodiment, the flow rate at which hydrogen is drawn is adjusted according to the pressure inside the collection chamber 20. For example, as shown in FIG. 1 , the drain bottle 40 is provided with a pressure sensor P as a detection unit. The pressure sensor P indirectly detects the pressure inside the collection chamber 20. The pressure sensor P and the adjustment valve 70 are electrically connected, and the flow rate of the adjustment valve 70 is adjusted according to the pressure inside the collection chamber 20. This allows hydrogen to be drawn appropriately from the collection chamber 20 without drawing the electrolyte 11 from the collection chamber 20 and preventing hydrogen from overflowing from the collection chamber 20. The location at which the pressure sensor P is provided is not limited to the drain bottle 40, and may be, for example, anywhere in the flow path L2.

[0035] Equipment for utilizing the recovered hydrogen is located downstream of the control valve 70. An example of such equipment is a baking furnace, which heat-treats and hardens the electrocoated coating formed on the surface of the aluminum material A after anodizing. Using the hydrogen recovered by the hydrogen recovery device 1 in a baking furnace is preferable because it allows for effective utilization of the hydrogen generated within a single aluminum processing facility. Meanwhile, the baking furnace is one example of a use of the hydrogen recovered by the hydrogen recovery device 1. Uses of the hydrogen include furnaces that use fuel in peripheral equipment and fuel cells, and are not limited to baking furnaces. For example, the downstream side of flow path L5 may be connected to a tank that stores hydrogen, and the hydrogen stored in the tank may be used for various purposes.

[0036] Other embodiments of the present disclosure will be described below. Configurations similar to those in the first embodiment will be denoted by the same reference numerals, and descriptions thereof may be omitted.

[0037] (Second embodiment) <Combustible gas recovery device> The configuration of the hydrogen recovery device 1a according to the second embodiment will be described below with reference to FIG. 4. FIG. 4 is a plan view schematically illustrating the hydrogen recovery device 1a. As shown in FIG. 4, the hydrogen recovery device 1a recovers hydrogen generated from five electrolytic cells 10a, 10b, 10c, 10d, and 10e. FIG. 4 schematically illustrates a row of cathodes 12 arranged in a row in the electrolytic cells. In this embodiment, four rows of cathodes 12 are arranged in one electrolytic cell. The number of rows of cathodes 12 and the number of electrolytic cells are not limited to those described above. Recovery chambers 21 and 22 are arranged on one side of the cathodes 12 in each row and on the other side opposite the one side, respectively. The recovery chambers 21 and 22 in each row are connected by a flow path 25. A flow path L1 may be connected to the recovery chambers 21 and 22 (not shown).

[0038] In the hydrogen recovery device 1a, the flow path L2 and the flow path 25 are connected via the flow path 26 and the flow path 27. The flow path 26 connects the flow path 25 corresponding to one row of cathodes 12 in one electrolytic cell with the flow path 25 corresponding to another row of cathodes 12 in another electrolytic cell. In this embodiment, the flow path 26 connects all of the flow paths 25 in one electrolytic cell to each other. The flow path 27 connects the flow path 26 in one electrolytic cell to the flow path 26 in another electrolytic cell. In this embodiment, the flow path 27 connects all of the flow paths 26 in all of the electrolytic cells to each other. That is, with the above configuration, all of the recovery chambers 21, 22 in the electrolytic cells 10a, 10b, 10c, 10d, and 10e are connected to each other via the flow paths 25, 26, and 27. This allows the equipment, such as the blower 60 arranged downstream of the flow path L2, to be shared and constituted as a single facility. This reduces the equipment costs of the hydrogen recovery device 1a.

[0039] The flow paths 25, 26, and 27 have a tournament structure in which they branch off in multiple stages. With this structure, for example, a valve can be provided at the connection point of flow path 27 with flow path 26 in the electrolytic cell 10a, and the valve can be closed when the electrolytic cell 10a is not in use. Alternatively, if a collection chamber in the electrolytic cell 10a is damaged, closing the valve can prevent hydrogen from flowing from a normal collection chamber into the damaged collection chamber. Alternatively, a valve can be provided at the connection point of flow path 26 with flow path 25, and when a certain row of cathodes 12 in the electrolytic cell is not in use, the valve corresponding to the row of cathodes 12 can be closed. This allows the hydrogen recovery device 1a to be operated in a favorable manner.

[0040] The hydrogen recovery device as the flammable gas recovery device according to each embodiment of the present disclosure has been described above. However, the present disclosure is not limited to the above-described embodiments and can be modified as appropriate. [Explanation of symbols]

[0041] 1, 1a hydrogen recovery device (combustible gas recovery device), 20, 21, 22 recovery chamber, 23a, 23b, 24 blocking material, P pressure sensor (detection part), 70 control valve (adjustment part)

Claims

1. It has a recovery chamber for recovering flammable gas generated from the liquid, The flammable gas recovery device, wherein the recovery chamber is immersed in the liquid.

2. The flammable gas recovery device according to claim 1 , wherein the flammable gas is hydrogen.

3. The flammable gas recovery device according to claim 1 , wherein the flammable gas is generated from a surface of an electrode immersed in an electrolytic solution.

4. The flammable gas recovery device according to claim 3 , wherein the recovery chamber comprises a pair of recovery chambers, one of which is disposed on one side of the electrode and the other of which is opposed to the one side.

5. The flammable gas recovery device according to claim 3 or 4, wherein a blocking material is disposed between the recovery chamber and the electrode.

6. A plurality of the electrodes are arranged in a row, The flammable gas recovery device according to claim 5, wherein a plugging material having an Asker hardness of 8 to 50 is disposed between adjacent electrodes.

7. a suction unit that sucks the flammable gas from the recovery chamber; At least some of the collection chambers are connected to each other, The flammable gas recovery device according to claim 1 , wherein the flammable gas recovered in the plurality of connected recovery chambers is sucked by the single suction section.

8. The flammable gas recovery device according to claim 7 , wherein the flow path connecting the plurality of recovery chambers has a tournament structure in which the flow path branches in a plurality of stages.

9. a suction unit that sucks the flammable gas from the recovery chamber; a detection unit that detects the pressure in the recovery chamber; an adjusting unit that adjusts the flow rate at which the flammable gas is sucked by the suction unit, The flammable gas recovery device according to claim 1 , wherein the adjustment unit adjusts the flow rate of the flammable gas sucked in according to the pressure in the recovery chamber detected by the detection unit.

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