Methane generation suppression device

Abstract

To provide a methane generation suppression device that is capable of suppressing methane generation with higher efficiency.SOLUTION: A methane generation suppression device 1 comprises a methane sensor and methane generation suppression means. The methane sensor detects whether methane is generated in a surrounding environment including soil. When the methane sensor detects methane generation, the methane generation suppression means inhibits the activity of methane-generating microorganisms in the soil of the surrounding environment and reduces the level of methane generation.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a methane generation suppression device for suppressing methane generation from paddy fields, farmland, and the like. [Background technology]

[0002] Methane gas is known as one of the greenhouse gases. Known sources of methane gas include natural sources such as wetland soil and oceans, as well as anthropogenic sources such as paddy field soil and livestock waste. Methane gas is responsible for approximately 23% of the impact of all greenhouse gases on global warming, and is known to have a stronger greenhouse effect than carbon dioxide when compared by weight, despite having a shorter average lifespan than carbon dioxide (approximately 10 years in the atmosphere).

[0003] For this reason, attempts are being made to suppress the generation of methane gas from, for example, paddy field soil, wetland soil, and the like.

[0004] For example, Patent Document 1 discloses a methane gas generation inhibitor consisting of magnesium oxide powder and / or magnesium hydroxide powder. This methane gas generation inhibitor is a powder having a particle size of 0.75 mm or less, and is added to an aqueous mixture of putrefactive organic matter such as wetland soil, paddy field soil, or livestock waste to suppress the generation of methane gas.

[0005] Patent Document 2 discloses a microbial preparation for suppressing the generation of harmful gases, such as methane, nitrogen compounds, and sulfides, which are generated in pastures, fields, rice paddies, lakes, marshes, or aquaculture ponds, and for reducing greenhouse gases on a global scale. This microbial preparation contains microorganisms belonging to the genera Bacillus, Lactobacillus, Strptococcus, Candida, and Pichia. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2010-115572 A [Patent Document 2] JP 2009-201354 A Summary of the Invention [Problem to be solved by the invention]

[0007] In this way, in order to suppress the generation of methane gas from a methane generation source, it has been proposed to add a methane generation suppression agent to the generation source. However, in conventional methane generation suppression methods, the amount of methane generated is not monitored, and it is not possible to add an agent according to the amount of methane generated, so that methane generation cannot be suppressed efficiently.

[0008] An object of the present invention is to provide a methane production suppression device that can more efficiently suppress methane production. [Means for solving the problem]

[0009] A methane generation suppression device according to one aspect of the present invention includes a methane sensor that detects the presence or absence of methane generation in a surrounding environment including soil, and a methane generation suppression means that, when the methane sensor detects the generation of methane, reduces the activity of methanogenic microorganisms contained in the soil of the surrounding environment, thereby reducing the amount of methane generated.

[0010] According to the above configuration, the methane sensor detects the presence or absence of methane generation in the surrounding environment, and the methane generation suppression means can be appropriately operated according to the detection result, so that methane generation can be more efficiently suppressed at the source of methane generation.

[0011] In the methane production suppression device according to one aspect of the present invention, the methane production suppression means may have an oxygen supplying unit that supplies oxygen to soil in the surrounding environment.

[0012] According to the above-mentioned configuration, oxygen can be supplied to the soil inhabited by methanogenic microorganisms, thereby reducing the activity of the anaerobic methanogenic microorganisms and suppressing the generation of methane from the soil.

[0013] In a methane generation suppression device according to one aspect of the present invention, the methane generation suppression device is used on water and may further include a floating body section for floating on the water and a drive section for moving on the water surface.

[0014] According to the above configuration, the methane generation suppression device can be suitably used on the water surface of, for example, a rice paddy, a pond, or the like. Effect of the Invention

[0015] According to an aspect of the present invention, a methane generation suppression device can more efficiently suppress methane generation in an environment where methane may be generated. [Brief description of the drawings]

[0016] [Figure 1] 1 is a schematic diagram showing a configuration of a methane production suppression device according to one embodiment. FIG. [Diagram 2] 2 is a schematic diagram showing an internal configuration of a methane detection unit provided in the methane generation suppression device shown in FIG. 1. [Diagram 3] 2 is a schematic diagram showing an internal configuration of a methane production suppression unit provided in the methane production suppression device shown in FIG. 1. [Figure 4] FIG. 1 is a schematic diagram showing an example of the configuration of a self-propelled methane generation suppression device. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In this embodiment, a methane generation suppression device for suppressing methane generation from paddy fields, farmland, ponds, etc. will be described as an example.

[0018] 1 shows the configuration of a methane generation suppression device 1 used on water. The methane generation suppression device 1 is configured to be movable on water. The methane generation suppression device 1 mainly includes a main body unit 10, a drive unit 20, and a floating body unit 31.

[0019] The main body 10 and the drive unit 20 are disposed on a floating body 31. The floating body 31 has the property of floating on water. For example, a small boat, a boat, a float, or the like can be used as the floating body 31. As a result, the main body 10, the drive unit 20, and the like of the methane generation suppression device 1 are floating on the water surface H.

[0020] The main body 10 includes a methane detector 11, an oxygen supplier 12, a controller 13, and the like.

[0021] Fig. 2 shows the internal configuration of the methane detection unit 11. The methane detection unit 11 has a methane sensor 41, a gas inlet 42, a gas outlet 43, a fan 44, and a sensor case 45. In Fig. 2, the flow of gas (air) passing through the sensor case 45 of the methane detection unit 11 is indicated by arrows.

[0022] The methane sensor 41 is disposed in a sensor case 45. The methane sensor 41 is, for example, a catalytic combustion type, an oxide semiconductor type, an electrochemical type, or other gas sensor. More specifically, the methane sensor 41 is a catalytic combustion type gas sensor. An example of a catalytic combustion type gas sensor is that described in Patent Document 3 (JP 2017-102132 A).

[0023] The methane sensor 41 detects whether or not methane is contained in the atmosphere. The methane sensor 41 may be capable of measuring the methane concentration in the atmosphere. In this case, the methane sensor 41 determines that methane is contained in the atmosphere when the measured methane concentration is equal to or greater than a predetermined value, and determines that methane is not contained in the atmosphere when the measured methane concentration is less than the predetermined value.

[0024] The gas inlet 42 is disposed at one end of the sensor case 45, and the gas outlet 43 is disposed at the other end of the sensor case 45. The fan 44 is disposed within the sensor case 45. In this embodiment, the fan 44 is disposed on a side closer to the gas inlet 42 within the sensor case 45 (this side is referred to as the upstream side of the gas flow). By operating the fan 44, an air flow is formed within the sensor case 45 that flows from the gas inlet 42 to the gas outlet 43.

[0025] The methane sensor 41 is disposed downstream of the fan 44 inside the sensor case 45. The methane sensor 41 detects the presence or absence of methane (CH4) contained in the air flowing inside the sensor case 45. Information relating to the detection result of methane by the methane sensor 41 is transmitted to the control unit 13.

[0026] In this embodiment, the methane sensor 41 detects the presence or absence of methane generation in the surrounding environment including soil. When the methane generation suppression device 1 is used in a paddy field or the like, the methane sensor 41 detects the presence or absence of methane generated from methanogenic microorganisms living in the soil S present under the water W in the paddy field.

[0027] 3 shows the internal configuration of the oxygen supply unit 12. The oxygen supply unit 12 has an oxygen supply mechanism 51. The oxygen supply unit 12 is connected to the control unit 13. The oxygen supply mechanism 51 in the oxygen supply unit 12 operates according to commands from the control unit 13.

[0028] The oxygen supply mechanism 51 has an oxygen supply pipe 52. The oxygen supply pipe 52 is a pipe that extends downward from the main body 10. The oxygen supply pipe 52 is configured to be extendable and retractable, and when the methane generation suppression device 1 moves on the water surface, the oxygen supply pipe 52 is contracted or folded and stored inside the oxygen supply mechanism 51.

[0029] Then, for example, at the timing when the methane sensor 41 detects the presence of methane, the oxygen supply pipe 52 extends downward from the main body 10 through the floating body 31, and the tip of the oxygen supply pipe 52 reaches the soil S located under the water W (see FIG. 3). In this state, the oxygen supply mechanism 51 starts supplying oxygen to the soil S. This allows oxygen to be supplied to the soil S.

[0030] The oxygen supply source in the oxygen supply mechanism 51 may be the atmosphere present in the vicinity of the methane generation suppression device 1, or may be an oxygen cylinder (not shown) attached to the oxygen supply mechanism 51. By using an oxygen cylinder as the oxygen supply source, a higher concentration of oxygen can be supplied to the soil S. The oxygen supply mechanism 51 may also have an oxygen concentration system, and may concentrate oxygen contained in the atmosphere in the surrounding environment and supply it to the soil.

[0031] The source of methane that occurs in paddy fields and wetland soils is methanogenic microorganisms that live in the soil. Methane-producing microorganisms include, for example, methanogens. Methanogens are archaea that synthesize methane under anaerobic conditions, and synthesize the majority of the methane released on Earth. Methanogens are also called methanogens.

[0032] Methanogenic microorganisms produce methane (CH4) in an anaerobic environment using carbon dioxide (CO2) and hydrogen (H2) as substrates. Because methanogenic microorganisms are anaerobic, they cannot survive or their activity decreases in environments with high oxygen (O2). Therefore, by supplying oxygen to the soil S in which the methanogenic microorganisms live, the activity of the methanogenic microorganisms can be reduced, and the production of methane from the soil S can be suppressed.

[0033] The oxygen supply unit 12 has the oxygen supply mechanism 51 as described above, and when the methane sensor 41 detects the generation of methane, it supplies oxygen to the soil S present in the location where methane is being generated. This reduces the activity of methanogenic microorganisms contained in the soil of the surrounding environment, and the amount of methane generated can be reduced. In this way, the oxygen supply unit 12 functions as a methane generation suppression means.

[0034] In this embodiment, the oxygen supply unit 12 is given as an example of the methane generation suppression means, but the methane generation suppression means is not limited to this. The methane generation suppression means may be any means capable of suppressing the activity of methanogenic microorganisms that cause methane generation when the methane sensor detects the generation of methane.

[0035] Other examples of methane generation suppression means include a method using a microbial preparation described in Patent Document 2, or a methane gas generation suppressor disclosed in Patent Document 1. The methane generation suppression means can reduce the amount of methane generation by supplying these preparations to soil in the surrounding environment when a methane sensor detects methane generation.

[0036] The control unit 13 is connected to each component part (e.g., the methane detection unit 11, the oxygen supply unit 12, the drive unit 20, etc.) in the methane generation suppression device 1 and controls them. The control unit 13 includes a CPU, a memory, a timer, etc.

[0037] For example, the control unit 13 can receive information on the presence or absence of methane generation from the methane detection unit 11 and cause the oxygen supply unit 12 to execute a predetermined operation. Furthermore, the control unit 13 can operate the drive unit 20 based on its own judgment or information transmitted from another device, and can move the methane generation suppression device 1 to a predetermined position.

[0038] The drive unit 20 includes a motor 21, a screw 22, a rudder 23, and a rechargeable battery 24 (see FIG. 1). The motor 21 starts and stops operation based on commands from the control unit 13 (more specifically, a drive control circuit in the control unit 13).

[0039] When the motor 21 is operated, the screw 22 rotates and the methane generation suppression device 1 moves on the water surface. At this time, the rudder 23 operates based on commands from the control unit 13 to determine the direction of travel of the methane generation suppression device 1. This allows the methane generation suppression device 1 to move on the water surface.

[0040] The methane production suppressing device 1 according to this embodiment may be one that moves to a predetermined location by its own initiative (so-called self-propelled type), or one that moves by remote control.

[0041] Fig. 4 shows the configuration of the self-propelled methane production suppression device 1. Note that in Fig. 4, the methane detection unit 11, the oxygen supply unit 12, and the like are omitted from the illustration.

[0042] The methane generation suppression device 1 shown in Fig. 4 is equipped with a camera 35. Information on the image captured by the camera 35 is transmitted to the control unit 13. The camera 35 captures an image of the periphery of the device 1 (for example, the periphery of the water surface of a rice paddy or the like) and transmits the result to the control unit 13, whereby the control unit 13 can move the methane generation suppression device 1 by operating the rudder 23 so as to avoid obstacles (for example, crops P such as seedlings or rice) contained in the captured image. This allows the methane generation suppression device 1 to be moved without damaging crops on the rice paddy or the like.

[0043] In the methane generation suppression device 1 according to this embodiment, when the device starts to move, the control unit 13 operates the fan 44 and the methane sensor 41 monitors the amount of methane generation in the environment surrounding the device 1. Then, when the methane sensor 41 confirms the generation of methane, the control unit 13 stops the movement of the methane generation suppression device 1 and starts the supply of oxygen from the oxygen supply unit 12 to the soil. This reduces the activity of methanogenic microorganisms living in the soil, making it possible to suppress methane generation.

[0044] The methane sensor 41 may be capable of not only determining whether methane is present in the atmosphere of the surrounding environment, but also measuring the methane concentration in the atmosphere (amount of methane generated). In this case, the methane sensor 41 may monitor the amount of methane generated, and the oxygen supply unit 12 may supply an appropriate amount of oxygen to the soil according to the monitored amount of methane generated.

[0045] (Summary of the embodiment) The methane generation suppression device 1 according to this embodiment includes a methane sensor 41 and a methane generation suppression means. The methane sensor 41 detects the presence or absence of methane generation in the surrounding environment including soil. When the methane sensor detects the generation of methane, the methane generation suppression means reduces the activity of methanogenic microorganisms contained in the soil of the surrounding environment, thereby reducing the amount of methane generated.

[0046] The methane generation suppression means is realized, for example, by supplying oxygen to the soil in the surrounding environment. In this embodiment, the methane generation suppression means has an oxygen supply unit 12 that supplies oxygen to the soil in the surrounding environment.

[0047] In the past, the amount of methane generated in methane-generating environments such as rice paddies was not monitored, and it was not possible to add appropriate materials depending on the amount of methane generated, making it difficult to efficiently suppress methane generation.

[0048] In contrast, in the methane generation suppression device 1 according to the present embodiment, the methane sensor 41 detects the presence or absence of methane generation in the surrounding environment, and the oxygen supply unit 12 operates appropriately according to the detection result, thereby supplying oxygen to the location where methane is being generated. This enables more efficient suppression of methane generation.

[0049] In this embodiment, the methane generation suppression device 1 that moves while floating on water has been described as an example, but the methane generation suppression device 1 is not limited to use on water and can also be used on land, such as on farms, swamps, etc. When using the methane generation suppression device 1 on land, the drive unit 20 is provided with a moving means (for example, wheels, etc.) suitable for movement on land.

[0050] As described above, the methane generation suppression device 1 according to the present embodiment can suppress methane generation more efficiently. Therefore, the methane generation suppression device 1 can be used as a measure against global warming in agriculture.

[0051] The embodiments disclosed herein should be considered to be illustrative and not restrictive in all respects. The scope of the present invention is indicated by the claims, not by the above description, and is intended to include all modifications within the meaning and scope of the claims. In addition, configurations obtained by combining the configurations of the different embodiments described in this specification are also included in the scope of the present invention. [Explanation of symbols]

[0052] 1: Methane emission suppression device 10: Main body 11: Methane detector 12: Oxygen supply unit (means for suppressing methane generation) 13: Control section 20: Drive unit 31: Floating body section 35: Camera 41: Methane sensor 44: Fan 51: Oxygen supply mechanism 52: Oxygen supply pipe

Claims

1. a methane sensor that detects the presence or absence of methane generation in a surrounding environment including soil; a methane generation suppression means for suppressing the activity of methanogenic microorganisms contained in the soil of the surrounding environment when the methane sensor detects the generation of methane, thereby reducing the amount of methane generated; A methane emission suppression device comprising:

2. 2. The methane generation suppression device according to claim 1, wherein the methane generation suppression means has an oxygen supplying section that supplies oxygen to the soil in the surrounding environment.

3. The methane generation suppression device is used on water, A floating body for floating on the water; A drive unit for moving on the water surface and Further comprising: The methane generation suppression device according to claim 1 or 2.

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