JP2021071434A - Floating sensor - Google Patents

Abstract

To provide a floating sensor capable of easy inspection with a simple device.SOLUTION: A floating sensor 100 includes a cathode supporter 110 supporting a cathode electrode 11, an anode supporter 120 supporting an anode electrode 12, and a floating member 14 floating the cathode supporter and the anode supporter on a water surface in a manner that the anode electrode supported by the anode supporter is a lower surface and the cathode electrode supported by the cathode supporter is an upper surface. The anode supporter supports the anode electrode so that the anode electrode is in contact with the cathode electrode with an exchange film 13 held therebetween. The anode supporter supports the anode electrode so that the anode electrode can be separated from the cathode supporter.SELECTED DRAWING: Figure 4

Description

The present disclosure relates to a floating sensor.

Organic substances (hereinafter referred to as organic substances) in water such as factory wastewater are decomposed by microorganisms. At that time, the water quality deteriorates due to the consumption of oxygen in the water. Therefore, from the viewpoint of water quality conservation, it is important to inspect whether or not organic matter is present in the water.

Here, there is known a power generation device that generates electricity by converting an organic fuel into electric energy by utilizing a metabolic reaction of microorganisms. For example, Japanese Patent Application Laid-Open No. 2015-95274 (hereinafter, Patent Document 1) and Japanese Patent Application Laid-Open No. 2015-204198 (hereinafter, Patent Document 2) disclose an apparatus for generating electricity by decomposing organic substances by microorganisms in water.

Japanese Unexamined Patent Publication No. 2015-95274 JP 2015-204198

It is conceivable to use such a power generation device as a sensor for detecting the presence or absence of organic substances in water. However, in order to use this power generation device, it takes time and effort to put the liquid to be inspected in a container and set the electrodes.

On the other hand, there are many needs for inspection of whether or not organic matter is present in water, such as wastewater from factories, pools, public baths, and rivers. Therefore, we provide a floating sensor that can be inspected without hassle with a simple device.

According to an embodiment, the floating sensor has a cathode support that supports the cathode electrode, an anode support that supports the anode electrode, and an anode electrode that is supported by the anode support on the lower surface and the cathode support. With the cathode electrode as the upper surface, the cathode support and the float member for suspending the anode support on the water surface are provided, and the anode support supports the anode electrode so as to be in contact with the cathode electrode with an exchange film in between. The anode support supports the anode electrode separably with respect to the cathode support.

Further details will be described as embodiments described below.

FIG. 1 is a schematic view of a sensing system according to an embodiment. FIG. 2 is a schematic plan view of the floating sensor according to the embodiment. FIG. 3 is a schematic bottom view of the floating sensor according to the embodiment. FIG. 4 is a schematic AA cross-sectional view of the floating sensor according to the embodiment. FIG. 5 is a schematic cross-sectional view of the BB of the floating sensor according to the embodiment. FIG. 6 is a developed view of the floating sensor according to the embodiment. FIG. 7 is a schematic plan view of the float member included in the floating sensor. FIG. 8 is a schematic bottom view of the float member included in the floating sensor.

<1. Overview of floating sensor>

(1) The floating sensor included in the present embodiment has a cathode support that supports the cathode electrode, an anode support that supports the anode electrode, and an anode electrode supported by the anode support on the lower surface and the cathode support. With the supported cathode electrode as the upper surface, the anode support and the float member for suspending the anode support on the water surface are provided, and the anode support is in contact with the cathode electrode with an exchange film in between. Supporting, the anode support supports the anode electrode separably with respect to the cathode support.

As a result, by floating on the water surface to be sensed, power is generated according to the organic matter in the water, and the organic matter can be sensed by the power generation. Therefore, the water quality can be inspected without hassle with a simple device.

(2) Preferably, the anode support has a storage space for accommodating the anode electrode, which is concave from the lower surface. As a result, the anode electrode can be brought into contact with water by floating.

(3) Preferably, the anode support includes a member that holds the anode electrode accommodated in the accommodation space by pressing the anode electrode from the lower surface toward the bottom of the accommodation space. As a result, the anode electrode can be attached and detached with a simple structure.

(4) Preferably, the anode support has a ventilation path penetrating from the accommodation space to the upper surface. As a result, when the air is suspended on the water surface, the air in the accommodation space can be exhausted, and the air can be stably suspended.

(5) Preferably, the ventilation path further has a function of guiding the terminal extending from the anode electrode accommodated in the accommodating space from the accommodating space to the upper surface. This allows the circuit to be placed above the surface of the water.

(6) Preferably, the float member is removable from the cathode support. This makes it easy to handle.

(7) Preferably, the anode electrode constitutes a retainer that retains the microorganisms in a dry state. As a result, power generation is performed by utilizing the decomposition of organic matter by microorganisms held on the anode electrode.

(8) Preferably, the float member is equipped with a circuit for connecting the anode electrode and the cathode electrode. As a result, the anode electrode and the cathode electrode can be easily electrically connected.

(9) Preferably, the float member is further equipped with an antenna for transmitting the electric power generated by the circuit. Thereby, the sensing result can be easily obtained.

<2. Floating sensor example>

With reference to FIG. 1, the sensing system 300 includes a floating sensor 100 and a receiving device 200. The floating sensor 100 functions as a power generation device that generates electricity by converting fuel, which is an organic substance, into electric energy by utilizing the metabolic reaction of microorganisms. The floating sensor 100 floats on the surface of the water to be sensed. The floating sensor 100 generates electricity using fuel, which is an organic substance in water. The floating sensor 100 further has an antenna 20 and radiates the generated electric power. The receiving device 200 receives the electric power radiated from the antenna 20.

With reference to FIGS. 2 to 6, the floating sensor 100 generates electricity by utilizing the action of microorganisms decomposing fuel, which is an organic substance, and functions as an anode electrode 12, a cathode electrode 11, and a separator. The exchange membrane 13 is provided.

The floating sensor 100 further includes a cathode support 110 and an anode support 120 as a housing for supporting them. Further, the floating sensor 100 further has a fixed body 130 for fixing the anode support 120 to the cathode support 110. Each member constituting the cathode support 110, the anode support 120, and the fixed body 130 is a flat plate-shaped member as described later, and is a light and easy-to-process material such as an acrylic plate. This facilitates manufacturing. Preferably, it is a recyclable material. This makes the product environmentally friendly. Preferably, it is a low cost material. As a result, the overall cost increase can be suppressed.

The cathode support 110 supports the cathode electrode 11. The cathode electrode 11 is a so-called air cathode having oxygen permeability. Specifically, the cathode electrode 11 is a conductive coating containing carbon as a main component, and is produced, for example, by mixing multi-walled carbon nanotubes, activated carbon powder, and a naphthion solution and drying them. The cathode electrode 11 thus generated is recyclable. This makes the product environmentally friendly. The cathode electrode 11 is used in a state of being attached to the stainless mesh 10. By using the stainless mesh 10, the electrical contact layer of the cathode electrode 11 can be easily constructed.

The cathode support 110 includes a support member 6 and a frame member 7. The support member 6 is a flat plate-shaped rectangular member having a thickness of about 3 mm. An opening 61 is provided near the center of the support member 6. Further, through holes 62A and 62B and through holes 63A and 63B are provided in the vicinity of both sides facing each other in parallel with the sides. One surface of the support member 6 is the upper surface, and the other surface is the lower surface.

The frame member 7 is a flat plate-shaped rectangular frame smaller than the support member 6, and has a thickness of about 2 mm. The frame member 7 is installed on the upper surface of the support member 6 so that the space 71 in the frame overlaps the opening 61 and the frame member 7 does not overlap the through holes 62A and 62B and the through holes 63A and 63B.

The cathode electrode 11 and the stainless mesh 10 are set in the frame inner space 71 with the stainless mesh 10 side as the upper surface. Therefore, the region in contact with the frame inner space 71 and the frame inner space 71 of the support member 6 constitutes a first accommodation space which is an accommodation space for the concave cathode electrode 11 and the stainless mesh 10 from the upper surface side.

The upper part of the frame space 71 is open. Therefore, as shown in FIG. 2, the electrical contact 17 of the cathode electrode 11 formed by the stainless mesh 10 to which the cathode electrode 11 is added can be exposed upward.

The anode support 120 supports the anode electrode 12 supported by the cathode support 110 so as to be in contact with the cathode electrode 11 with the exchange membrane 13 interposed therebetween. The exchange membrane 13 is, for example, a naphthion membrane. The exchange membrane 13 is permeable to protons (hydrogen ions) generated in the vicinity of the anode electrode 12 and prevents the permeation of water in the vicinity of the anode electrode 12. The exchange membrane 13 is recyclable. This makes the product environmentally friendly.

The anode electrode 12 is a conductive coating containing carbon as a main component, and is, for example, an activated carbon sheet in which activated carbon is mixed with a carbon sheet. The anode electrode 12 is used in a state of being attached to both surfaces of the stainless mesh 10. By using the stainless mesh 10, the electrical contact layer of the anode electrode 12 can be easily constructed.

The anode electrode 12 may hold a microorganism that decomposes organic substances. In this case, the anode electrode 12 constitutes a "retainer" for retaining microorganisms. Since the floating sensor 100 is in a dry state when not in use, the anode electrode 12 is in a dry state. The microorganism held by the anode electrode 12 is preferably a microorganism that can survive for a long period of time in a dry state, and is, for example, Bacillus subtilis such as Bacillus natto. The retained microorganism is not limited to Bacillus subtilis and may be another microorganism that can survive in a dry state. For example, yeast, Escherichia coli, etc. that decompose glucose may be used. Since these microorganisms are safe for the human body and easily available, the floating sensor 100 can be easily manufactured and handled. The anode electrode 12 does not have to hold microorganisms that decompose organic substances. In this case, power generation is performed by utilizing the decomposition of organic matter by microorganisms in water.

The fixed body 130 fixes the anode support 120 to the cathode support 110 so that the anode support 120 supports the anode electrode 12 separably from the cathode support 110. The fixed body 130 will be described later.

The anode support 120 includes a frame member 5 and a locking member 4 in addition to the support member 6 described above. Neither the frame member 5 nor the locking member 4 is fixed to the support member 6, but is a separate member, and is fixed by the fixing body 130 described later.

The frame member 5 is a flat plate-shaped rectangular frame having the same or substantially the same size as the support member 6, and has a thickness of about 2 mm. The frame member 5 is in contact with the lower surface side of the support member 6, and is installed around the opening 61 with the exchange membrane 13 in between so that the frame inner space 51 overlaps with the opening 61. The surface of the frame member 5 facing the support member 6 is the upper surface, and the surface on the opposite side is the lower surface.

The support member 6, the frame member 5, and the frame member 7 are stacked in a state where the cathode electrode 11 and the stainless mesh 10 are accommodated in the first accommodation space, and are fixed by an adhesive or the like. Therefore, the cathode electrode 11 and the stainless mesh 10 are securely fixed to the cathode support 110. This facilitates handling.

As another example, the support member 6, the frame member 5, and the frame member 7 may not be fixed. In that case, the support member 6, the frame member 5, and the frame member 7 can be attached to and detached from each other by the fixed body 130. Therefore, the cathode electrode 11 and the stainless mesh 10 can be separated from the cathode support 110. As a result, the cathode electrode 11 and the stainless mesh 10 can be easily replaced.

The anode electrode 12 and the stainless mesh 10 can be set in the frame inner space 51 of the frame material 5. Therefore, the region in contact with the frame inner space 51 and the frame inner space 51 of the support member 6 with the exchange membrane 13 sandwiched between them is the second accommodation space in which the concave anode electrode 12 and the stainless mesh 10 are accommodated from the lower surface side. Make up the space.

Notches 52A and 52B continuous with the space inside the frame 51 are formed at positions overlapping the through holes 62A and 62B of the support member 6 of the frame member 5, respectively. As a result, when the cathode support 110 and the anode support 120 are overlapped, the notch 52A and the through hole 62A and the notch 52B and the through hole 62B are connected, and these two places penetrate from the lower surface to the upper surface. To do.

Through holes 53A and 53B are provided at positions of the frame member 5 that coincide with the through holes 63A and 63B when they are overlapped with the support member 6, respectively. As a result, when the cathode support 110 and the anode support 120 are overlapped, the through hole 53A and the through hole 63A and the through hole 53B and the through hole 63B are connected from the lower surface to the upper surface, and these two places are connected. It penetrates from the bottom surface to the top surface.

The locking member 4 is a flat plate-shaped member having a size fitted into the frame inner space 51 of the frame member 5. The locking member 4 is fitted from the lower surface in a state where the anode electrode 12 and the stainless mesh 10 are accommodated in the second accommodation space. The locking member 4 is fixed together with the anode support 120 to the cathode support 110 by the fixing body 130. As a result, the locking member 4 presses the anode electrode 12 and the stainless mesh 10 accommodated in the second accommodation space from below to above, that is, toward the bottom of the second accommodation space, thereby pressing the anode electrode 12. Hold it. As a result, the anode electrode 12 and the stainless mesh 10 are locked in the second accommodation space to prevent them from falling downward.

The locking member 4 prevents the anode electrode 12 from falling downward while ensuring exposure on the lower side. Therefore, as shown in FIGS. 2 to 5, the locking member 4 has a frame shape and has an in-frame space 41. As a result, the exposure of the lower side of the anode electrode 12 can be ensured, and the anode electrode 12 comes into contact with water when suspended on the water surface.

Preferably, the locking member 4 is formed with cutouts 42A and 42B that are continuous with the frame inner space 41 at positions corresponding to the cutouts 52A and 52B when they are overlapped with the frame member 5. As a result, the space 41 in the frame is connected to the notches 52A and 52B, respectively, via the notches 42A and 42B. The cutouts 52A and 52B are connected to the through holes 62A and 62B of the support member 6, respectively, as described above. As a result, the space 41 in the frame is connected to the upper surface by the notch 52A and the through hole 62A, and the notch 52B and the through hole 62B, respectively, through the notches 42A and 42B, and two through holes are formed. Is forming.

The space 41 in the frame is connected to the upper surface via the notch 52A and the through hole 62A and the notch 52B and the through hole 62B to form two through holes. The holes can be air vents in the second containment space. As a result, the air in the second accommodation space can be exhausted and can be stably suspended on the water surface.

Further, one of the two through holes is also used as a guide for the terminals of the anode electrode 12 accommodated in the second accommodation space. The tip of the terminal of the anode electrode 12 constitutes the electrical contact 16 of the anode electrode 12 formed by the stainless mesh 10 to which the anode electrode 12 is added. As a result, as shown in FIG. 2, the electrical contact 16 of the anode electrode 12 fixed downward is guided to the upper surface.

The fixed body 130 includes a fixing member 2 and a fixing member 3, a first fixing rod 1, a second fixing rod 8, and a third fixing rod 9. The fixing member 2 and the fixing member 3 have the same shape, are flat plate-shaped members, and have a thickness of about 2 mm. The length of the fixing member 2 and the fixing member 3 in the width direction orthogonal to the longitudinal direction is smaller than the widths of the through hole 53A and the through hole 63A, and the through hole 53B and the through hole 63B. Therefore, in the fixing member 2 and the fixing member 3, the longitudinal direction is made to coincide with the thickness direction of the overlapping support member 6, the frame material 5, and the frame material 7, and the support member 6, the frame material 5, and the frame material 7 are aligned with each other. It is possible to insert and remove the through holes 53A and 63A, and the through holes 53B and 63B, which communicate from the lower surface to the upper surface in a state where the 7s are stacked, respectively.

At one end of the fixing member 2 and the fixing member 3, protrusions 24 and 34 protruding in at least one direction in the width direction are formed. Preferably, as shown in FIG. 6, the protrusions 24, 34 project to both sides in the width direction. As a result, when the fixing member 2 and the fixing member 3 are inserted into the through hole 53A and the through hole 63A, and the through hole 53B and the through hole 63B, respectively, it becomes easy to maintain the penetration state.

The fixing member 2 and the fixing member 3 are provided with first through holes 21, 31, second through holes 22, 32, and third through holes 23, 33, respectively, at the same positions. The first through holes 21, 31, the second through holes 22, 32, and the third through holes 23, 33 are arranged from the lower surface to the upper surface in this order. The first through holes 21 and 31 are through holes for passing the first fixing rod 1, the second through holes 22 and 32 are through holes for passing the second fixing rod 8, and the third through holes 23 and 33 are. It is a through hole for passing the third fixing rod 9.

The fixing rods 1, 8 and 9 are all flat plate-shaped members and have a thickness of about 2 mm. The fixing rods 1, 8 and 9, respectively, have the first through holes 21, 31 and the second through holes 22, 32 in the length direction parallel to the surfaces of the support member 6, the frame member 5, and the frame member 7, respectively. , And are inserted so as to penetrate both the third through holes 23 and 33. Therefore, each of the fixing rods 1, 8 and 9 is longer than the width in the direction of being sandwiched between the overlapping support member 6, the frame member 5, and the fixing member 2 and the fixing member 3 of the frame member 7.

Preferably, one end of the fixing rods 1, 8 and 9 in the longitudinal direction has protrusions 111, 81, 91 protruding in a direction at an angle with respect to the longitudinal direction, respectively, as shown in FIG. Is formed. As a result, the fixing rods 1, 8 and 9 are formed by the through holes formed by the first through holes 21 and 31, the through holes formed by the second through holes 22 and 32, and the third through holes 23 and 33, respectively. When inserted into the formed through hole, it becomes easier to maintain the intrusive state.

The distance between the first through holes 21 and 31 and the second through holes 22 and 32 is the thickness of the frame member 7, the thickness of the support member 6, the thickness of the exchange membrane 13, and the thickness of the anode electrode 12 and the stainless mesh 10. And the thickness of the locking member 4, which corresponds to the added length. As a result, the fixed cathode support 110 and the anode support 120 are made into the fixed rods 1 and 8 by passing the fixing rods 1 and 8 through the first through holes 21, 31 and the second through holes 22, 32, respectively. It is sandwiched in the thickness direction.

The fixing rods 1 and 8 can be inserted and removed from the first through holes 21 and 31 and the second through holes 22 and 32. The members 4 to 7 are stacked one above the other, the anode electrode 12 and the stainless mesh 10 are set in the second accommodating space, and the fixing rods 1 and 8 are placed in the first through holes 21, 31 and the second through holes 22, 32, respectively. By inserting, the anode support 120 is fixed to the cathode support 110. That is, the floating sensor 100 can be easily constructed. The fixed cathode support 110 and the anode support 120 described below refer to those in which the anode support 120 is fixed to the cathode support 110 by inserting the fixing rods 1 and 8.

Further, by removing the fixing rods 1 and 8 from the first through holes 21, 31 and the second through holes 22, 32, the anode support 120 is separated from the cathode support 110, and the anode electrode 12 and the stainless mesh 10 are separated. Leaves the second containment space. As a result, the floating sensor 100 can be easily disassembled, and the anode electrode 12 can be easily replaced.

The floating sensor 100 further includes a float member 14. The float member 14 has a flat plate-like shape, and is made of a material that floats on water, such as styrofoam. The thickness is, for example, about 5 mm.

As shown in FIGS. 7 and 8, the float member 14 has an opening 141. The opening 141 has a size equal to or larger than the size of the support member 6, and the fixed cathode support 110 and the anode support 120 can be fitted into the opening 141.

Preferably, the float member 14 has an eaves 142 formed at least in part around the opening 141, as shown in FIGS. 8 and 9. The eaves 142 has one of the upper surface side and the lower surface side of the float member 14 projecting inward from the edge of the other opening 141. In the examples of FIGS. 7 and 8, the eaves 142 overhanging on the upper surface side are formed. By forming such an eaves 142, when the cathode support 110 and the anode support 120 fixed from the side opposite to the eaves 142, in this example, the lower surface side, are fitted into the opening 141, the eaves The portion 142 interferes with the edge portion of the cathode support 110, and the fitted state is maintained. As a result, it is possible to prevent the cathode support 110 and the anode support 120 from falling off from the float member 14.

The distance between the first through holes 21, 31 and the third through holes 23, 33 corresponds to the thickness of the float member 14. Each of the fixing rods 1 and 9 is longer than the width in the direction sandwiched between the fixed cathode support 110 and the fixing member 2 and the fixing member 3 of the anode support 120. As a result, the cathode support 110 and the anode support 120 fixed to the opening 141 of the float member 14 are fitted, and the fixing rods 1 and 9 penetrate through the first through holes 21, 31 and the third through holes 23, 33, respectively. The cathode support 110 supporting the cathode electrode 11 and the stainless mesh 10 and the anode support 120 supporting the anode electrode 12 and the stainless mesh 10 are thickened by the fixing rods 1 and 8 via the exchange membrane 13. It is sandwiched in the direction.

The fixing rods 1 and 9 can be inserted and removed from the first through holes 21 and 31 and the third through holes 23 and 33. By removing the fixing rods 1 and 9 from the first through holes 21, 31 and the third through holes 23, 33, respectively, the cathode support 110 and the anode support 120 can be separated from the float member 14. As a result, the cathode support 110 and the anode support 120 are separably supported with respect to the float member 14. That is, the float member 14 can be attached to and detached from the cathode support 110. This facilitates the handling of the floating sensor 100.

An external circuit (load resistance) 18 is arranged on the upper surface of the float member 14 as shown in FIGS. 2 and 7, and the electrical contacts 16 of the anode electrode 12 and the electrical contacts 17 of the cathode electrode are drawn out on the upper surface. Connecting. As a result, the anode electrode 12 and the cathode electrode 11 are electrically connected by electrical wiring via an external circuit (load resistance) 18.

The floating sensor 100 is used by placing the cathode support 110 and the anode support 120 on the water surface with the cathode support 110 on the upper side and the anode support 120 on the lower side in a state where the cathode support 110 and the anode support 120 are fixedly attached to the float member 14. The floating sensor 100 floats on the water surface by the buoyancy of the float member 14. That is, in the float member 14, the cathode support 110 and the anode support 120 are suspended on the water surface with the anode electrode 12 supported by the anode support 120 as the lower surface and the cathode electrode 11 supported by the cathode support 110 as the upper surface. ..

When the floating sensor 100 is suspended on the water surface, the anode electrode 12 is located in the water and comes into contact with the water. In this state, microorganisms held in the anode electrode 12 or microorganisms in the water decompose organic substances in the water to generate protons and electrons. The electrons are collected at the anode electrode 12 and move to the cathode electrode 11 via the external circuit 18. Protons pass through the exchange membrane 13 and move to the cathode electrode 11. At the cathode electrode 11, water is generated by the reaction between oxygen obtained from the outside air in contact with the cathode electrode 11 and the electrons and protons that have moved to the cathode electrode 11.

As shown in FIG. 2, an antenna 20 is further connected to the external circuit 18 arranged on the upper surface of the float member 14. In FIG. 2, the antenna 20 is included in the communication module 20A, and the communication module 20A is connected to the external circuit 18.

The generated power is radiated from the antenna 20. By receiving this radiation with the receiving device 200, it is detected that the floating sensor 100 has generated power. It is also possible to detect the amount of power generated by the floating sensor 100 based on the received electric power. Thereby, it is possible to detect that a predetermined amount of organic matter is contained in the water to be sensed.

The sensing system 300 using the floating sensor 100 is suitably used for remotely managing the water quality. For example, drainage from factories and water quality management of pools, public baths, rivers, etc. are assumed. In this case, since it is used outdoors or in a public space, it is conceivable that the floating sensor 100 may be lost or damaged. Even in such a case, the floating sensor 100 is lightweight, is made of a relatively inexpensive material, and is easy to construct and disassemble, so that it can be easily used.

<3. Addendum>
The present invention is not limited to the above embodiment, and various modifications are possible.

1: 1st fixing rod 2: Fixing member 3: Fixing member 4: Locking member 5: Frame material 6: Support member 7: Frame material 8: 2nd fixing rod 9: 3rd fixing rod 10: Stainless mesh 11: Cathode Electrode 12: Anode electrode 13: Replacement film 14: Float member 16: Electrical contact 17: Electrical contact 18: External circuit 20: Antenna 20A: Communication module 21: First through hole 22: Second through hole 23: Third through hole 24: Protrusion 31: First through hole 32: Second through hole 33: Third through hole 34: Protrusion 41: In-frame space 42A: Notch 51: In-frame space 52A: Notch 52B: Notch 53A: Through hole 53B: Through hole 61: Opening 62A: Through hole 62B: Through hole 63A: Through hole 63B: Through hole 71: In-frame space 81: Projection 91: Projection 100: Floating sensor 110: Cathode support 111: Projection 120: Anode support Body 130: Fixed body 141: Opening 142: Anode 200: Receiver 300: Sensing system

Claims (9)

A cathode support that supports the cathode electrode and
An anode support that supports the anode electrode and
With the anode electrode supported by the anode support as the lower surface and the cathode electrode supported by the cathode support as the upper surface, the cathode support and the float member for suspending the anode support on the water surface are provided.
The anode support supports the anode electrode with an exchange membrane in between so as to be in contact with the cathode electrode.
The anode support is a floating sensor that supports the anode electrode in a separable manner with respect to the cathode support. The floating sensor according to claim 1, wherein the anode support has a concave shape from the lower surface and has a storage space for accommodating the anode electrode. The floating sensor according to claim 2, wherein the anode support includes a member that holds the anode electrode accommodated in the accommodation space by pressing the anode electrode from the lower surface toward the bottom of the accommodation space. The floating sensor according to claim 2 or 3, wherein the anode support has a ventilation path penetrating from the accommodation space to the upper surface. The floating sensor according to claim 4, wherein the ventilation path further has a function of guiding a terminal extending from the anode electrode accommodated in the accommodation space from the accommodation space to the upper surface. The floating sensor according to any one of claims 1 to 5, wherein the float member is removable from the cathode support. The floating sensor according to any one of claims 1 to 6, wherein the anode electrode constitutes a retainer that holds microorganisms in a dry state. The floating sensor according to any one of claims 1 to 7, wherein the float member includes a circuit for connecting the anode electrode and the cathode electrode. The floating sensor according to claim 8, wherein the float member further includes an antenna for transmitting electric power generated by the circuit.

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