Sediment removal system and sediment removal method

Abstract

This invention provides a sediment removal system that can detect pipe blockages at an early stage. [Solution] A sediment removal system 1 for removing sediment T accumulated in a pipe 50 through which fermentation residue from a methane fermentation tank 2 flows, comprising: a temperature detection means 51 for detecting the temperature of the pipe 50; and a determination means 6 for determining the blockage status of the pipe 50 based on the temperature or temperature information related to the temperature detected by the temperature detection means 51.

Description

Technical Field

[0001] The present invention relates to a sediment removal system and a sediment removal method for removing sediments deposited in a pipe through which fermentation residues flow from a methane fermentation tank.

Background Art

[0002] Conventionally, a technology for methane-fermenting organic wastes such as food waste to produce methane gas has been known. The recovered methane gas can be used for a variety of purposes such as gas engine power generation, fuel cells, and fuel for automobiles. On the other hand, the fermentation residues generated after producing methane gas are discharged from the methane fermentation tank, flow through a pipe, and are either re-introduced into the methane fermentation tank or sent to a dehydrator.

[0003] The fermentation residues may contain not only organic substances such as sludge but also inorganic substances such as sand, shells, and metals that were contained in garbage and the like. Since inorganic substances gradually accumulate inside the pipe through which the fermentation residues flow from the methane fermentation tank, there has been a problem that the flow path of the pipe is narrowed by the sediment, resulting in blockage (clogging) of the pipe. Therefore, a methane fermentation apparatus that can detect clogging of a pipe and remove sediment has been proposed (see, for example, Patent Document 1).

[0004] The methane fermentation apparatus of Patent Document 1 detects clogging of a pipe by measuring the internal pressure of the pipe, and eliminates the clogging of the pipe by controlling the opening and closing of the inlet valve and the outlet valve of the pipe.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] In the methane fermentation apparatus described in Patent Document 1, pipe blockage is detected when the internal pressure of the pipe, measured by a pressure gauge, exceeds a threshold. However, since the internal pressure of the pipe does not rise unless a considerable amount of sediment has accumulated in the pipe, it takes time before pipe blockage is detected. Therefore, when pipe blockage is detected by the rise in internal pressure, it may not be possible to resolve the blockage by simply controlling the opening and closing of the inlet and outlet valves of the pipe, and ultimately it was necessary to remove the sediment from the pipe manually. Furthermore, during the period of manual sediment removal, it was necessary to temporarily stop the input of waste into the methane fermentation apparatus, which resulted in a decrease in processing capacity.

[0007] This invention has been made in view of the above-mentioned problems, and aims to provide a sediment removal system and a sediment removal method that can detect pipe blockage at an early stage. [Means for solving the problem]

[0008] The characteristic configuration of the sediment removal system according to the present invention, which solves the above problems, is as follows: A sediment removal system for removing sediment accumulated in pipes through which fermentation residue from a methane fermentation tank flows, A temperature detection means for detecting the temperature of the aforementioned pipe, A determination means for determining the blockage status of the piping based on the temperature or temperature information related to the temperature detected by the temperature detection means, The goal is to provide for it.

[0009] Since methane fermentation takes place at a predetermined temperature, in a steady state (when no sediment has accumulated in the piping), the temperature of the piping through which the fermentation residue from the methane fermentation tank flows is detected to be approximately the same as the temperature of the fermentation liquid in the methane fermentation tank. On the other hand, when sediment accumulates in the piping, the inorganic matter in the sediment provides insulation, causing the temperature of the piping to gradually decrease. This temperature decrease occurs before the internal pressure of the piping rises. Therefore, by monitoring the temperature of the piping, it is possible to determine whether the piping is blocked. The sediment removal system with this configuration utilizes the phenomenon of the piping temperature decreasing, and includes a temperature detection means for detecting the temperature of the piping, and a determination means for determining the blockage status of the piping based on the temperature or temperature information detected by the temperature detection means. Therefore, it is possible to detect piping blockage early based on the temperature of the piping.

[0010] In the sediment removal system according to the present invention, It is preferable to further provide a notification means for notifying the determination result obtained by the determination means.

[0011] This sediment removal system includes a notification means that notifies the results of the determination means. Therefore, if an abnormality occurs in the piping, the situation is quickly notified by the notification means. Consequently, appropriate countermeasures can be taken before the internal pressure of the piping rises.

[0012] In the sediment removal system according to the present invention, Preferably, the system further includes means for removing deposits from the aforementioned piping.

[0013] According to this configuration of sediment removal system, since it is equipped with sediment removal means for removing sediment from pipes, when sediment accumulates in the pipes, the sediment removal means removes the sediment, preventing blockage of the pipes.

[0014] In the sediment removal system according to the present invention, The aforementioned sediment removal means is preferably implemented by switching the flow direction of the fermentation residue.

[0015] According to the sediment removal system of this configuration, since the sediment removal means is realized by switching the flow direction of the fermentation residue, there is no need to provide a dedicated device for removing sediment, and sediment can be removed without manual labor.

[0016] In the sediment removal system according to the present invention, Preferably, the sediment removal means is an injection means for injecting high-pressure fluid.

[0017] According to the sediment removal system of this configuration, since the sediment removal means is an injection means for injecting high-pressure fluid, the sediment can be directly loosened, and the sediment can be removed more reliably.

[0018] In the sediment removal system according to the present invention, Preferably, the temperature information is temperature, temperature change range, or temperature change rate.

[0019] According to the sediment removal system of this configuration, based on the temperature information of temperature, temperature change range, or temperature change rate, the clogging state of the pipe can be accurately determined.

[0020] In the sediment removal system according to the present invention, Preferably, the pipe is a vent pipe.

[0021] According to the sediment removal system of this configuration, since the pipe to be removed of sediment is a vent pipe, sediment can be reliably removed even at a bent portion where sediment is particularly likely to accumulate.

[0022] The characteristic configuration of the sediment removal method according to the present invention for solving the above problems is A sediment removal method for removing sediment deposited in a pipe through which fermentation residue flows from a methane fermentation tank, A temperature detection step of detecting the temperature of the pipe, A determination step of determining the blockage status of the pipe based on the temperature detected in the temperature detection step or temperature information related to the temperature. It lies in including.

[0023] The sediment removal method of this configuration utilizes the phenomenon of the temperature of the pipe decreasing, and includes a temperature detection step of detecting the temperature of the pipe, and a determination step of determining the blockage status of the pipe based on the temperature detected in the temperature detection step or temperature information related to the temperature. Therefore, the blockage of the pipe can be detected early based on the temperature of the pipe.

Brief Description of the Drawings

[0024] [Figure 1] FIG. 1 is a schematic diagram showing the schematic configuration of a methane fermentation facility to which the sediment removal system of this embodiment is applied. [Figure 2] FIG. 2 is an explanatory diagram of the normal operation of the discharge path, where (a) shows the state where fermentation residues are flowing through the upper pipe, (a´) shows the state where fermentation residues are flowing through the lower pipe, and (b) shows the state where fermentation residues are flowing through the discharge pipe. [Figure 3] FIG. 3 is an explanatory diagram of the reverse operation of the discharge path, where (a) shows the state where fermentation residues are flowing through the discharge pipe, (b) shows the state where fermentation residues are flowing through the upper pipe, and (b´) shows the state where fermentation residues are flowing through the lower pipe. [Figure 4] FIG. 4 is an explanatory diagram of the normal operation of the return path, where (a) shows the state where fermentation residues are flowing through the intermediate pipe, and (b) shows the state where fermentation residues are flowing through the return pipe. [Figure 5] FIG. 5 is an explanatory diagram of the reverse operation of the return path, where (a) shows the state where fermentation residues are flowing through the return pipe, and (b) shows the state where fermentation residues are flowing through the intermediate pipe. [Figure 6] FIG. 6 is an explanatory diagram of the injection means. [Figure 7] FIG. 7 is a flowchart showing the procedure of the sediment removal method of the present invention.

Modes for Carrying Out the Invention

[0025] The present invention will now be described in detail with reference to the drawings. However, the present invention is not intended to be limited to the configuration described below. In this specification, methane gas is not limited to a gas consisting solely of methane, but may be a gas mainly composed of methane and containing carbon dioxide, etc. Furthermore, in the following embodiments, a methane fermentation facility that produces methane gas by fermenting organic waste, resource crops, or their waste will be used as an example. Examples of organic waste include food waste, human and animal waste, sludge, food processing residues, livestock waste, waste oil, animal fats and oils, agricultural crop residues, and organic wastewater from the food industry, paper industry, or livestock industry, etc. Examples of sludge include sewage treatment sludge, human waste treatment sludge, septic tank sludge, and treated sludge from factory wastewater generated from food factories, etc. Examples of resource crops include potatoes, sugar beets, rapeseed, sunflowers, wheat, chlorella, water hyacinths, corn, sugarcane, or waste generated in the processing of these crops.

[0026] <Overall Structure> Figure 1 is a schematic diagram showing the general configuration of a methane fermentation facility 100 to which the sediment removal system 1 of this embodiment is applied. As shown in Figure 1, the methane fermentation facility 100 comprises a methane fermentation tank 2, an organic waste supply unit 3, a methane gas recovery unit 4, and a sediment removal system 1 including a fermentation residue treatment unit 5 and a determination means 6. The operation of the fermentation residue treatment unit 5 and the determination means 6 is controlled by a control means 10. The following describes each component in detail.

[0027] <Methane fermentation tank> The methane fermentation tank 2 ferments organic waste obtained by simple sorting of waste from homes, offices, businesses, etc., or organic waste that has been separately collected, into methane fermentation. In this embodiment, the methane fermentation tank 2 has a horizontally elongated cylindrical body 20 with its axis (not shown) oriented horizontally, a one-side end face 21 that closes one end of the body 20, and a other-side end face 22 that closes the other end of the body 20. The methane fermentation tank 2 also has an organic waste supply port 23 provided on the one-side end face 21, an upper discharge port 24 provided on the upper part of the other-side end face 22, a lower discharge port 25 provided on the lower part of the other-side end face 22, and an intermediate discharge port 26 provided between the upper discharge port 24 and the lower discharge port 25. The methane fermentation tank 2 stores (contains) a fermented liquid obtained by fermenting organic waste while it flows from one end face 21 to the other end face 22, and is configured to fill the space above the liquid surface of the fermented liquid with methane gas. Inside the methane fermentation tank 2, a stirring paddle (not shown) is provided to gently agitate the fermented liquid in order to promote the release of gas from the fermented liquid.

[0028] If the methane fermentation facility 100 is a dry type, the solid matter concentration in the methane fermentation tank 2 is adjusted to approximately 8-40% by weight, and methane gas is produced by methane fermentation of organic waste in a high-temperature environment (45-65°C). On the other hand, if the methane fermentation facility 100 is a wet type, the solid matter concentration in the methane fermentation tank 2 is adjusted to approximately 10% by weight, or 10% by weight or less, and methane gas is produced by fermenting organic waste in a medium-temperature environment (30-45°C) or a high-temperature environment (45-65°C).

[0029] <Organic Waste Supply Department> The organic waste supply unit 3 comprises a pumping unit 31 and an organic waste supply pipe 32. The pumping unit 31, although not shown in detail in the illustrations, is configured to include, for example, a pump and control valves for controlling the amount and pressure of the waste being supplied. The organic waste supply pipe 32 connects the organic waste supply port 23 and the pumping unit 31. Prior to the organic waste supply unit 3, the organic waste to be used as raw material is subjected to pretreatment equipment (not shown) to homogenize the raw material by removing foreign matter and to adjust the moisture content to a level suitable for methane fermentation. The organic waste that has undergone such pretreatment is then pushed into the methane fermentation tank 2 from the organic waste supply port 23 by the organic waste supply unit 3. The organic waste that is pushed in gradually moves from the organic waste supply port 23 toward the upper outlet 24, the lower outlet 25, and the intermediate outlet 26, undergoing hydrolysis, acid formation, and methane formation reactions to be converted into methane gas. The fermentation residue remaining after the methane gas has been extracted is discharged from the upper outlet 24, the lower outlet 25, and the intermediate outlet 26.

[0030] <Methane Gas Recovery Department> In the body 20 of the methane fermentation tank 2, a gas vent 27 is provided at a predetermined position in the upper region (in this example, a position close to the other end face 22, but not limited to this). The methane gas recovery unit 4 extracts and recovers methane gas from the methane fermentation tank 2 through the gas vent 27. The methane gas recovery unit 4 is equipped with a methane gas discharge pipe 41. In the methane gas discharge pipe 41, the upstream end of the gas flow is connected to the gas vent 27 so that methane gas can be discharged outside the tank, and the downstream end of the gas flow is connected to a gas holder 43. The methane gas discharged from the methane fermentation tank 2 via the methane gas discharge pipe 41 is temporarily stored in the gas holder 43 and then effectively utilized. A gas purification device may be connected to the downstream side of the gas flow in the gas holder 43 or in the middle of the methane gas discharge pipe 41.

[0031] <Fermentation residue processing equipment> The fermentation residue treatment equipment 5 removes the fermentation residue generated after methane gas production from the methane fermentation tank 2, passes it through piping 50, and either reintroduces it into the methane fermentation tank 2 or sends it to the dewatering machine 78. The fermentation residue treatment equipment 5 has a discharge route 7 that sends the fermentation residue to the dewatering machine 78 and a return route 8 that reintroduces the fermentation residue into the methane fermentation tank 2. The fermentation residue may contain not only organic matter such as sludge, but also inorganic matter such as sand, seashells, and metals that were contained in garbage, etc., and gradually deposits of inorganic matter T (see Figure 6) accumulate inside piping 50 through which the fermentation residue from the methane fermentation tank 2 flows. The deposit removal system 1 removes the deposits T by controlling the fermentation residue treatment equipment 5 and the determination means 6.

[0032] The discharge route 7 removes fermentation residue from the upper outlet 24 and lower outlet 25 of the methane fermentation tank 2. The discharge route 7 includes a discharge pump 70 and piping 50 consisting of an upper pipe 71, a lower pipe 72, and a discharge pipe 73. One end of the discharge pipe 73 is connected to the discharge pump 70, and the other end is connected to a dewatering machine 78. A discharge gate 76 is provided in the middle of the discharge pipe 73. One end of the upper pipe 71 and the lower pipe 72 are connected to the upper outlet 24 and the lower outlet 25 so that the fermentation residue can be discharged outside the methane fermentation tank 2. The other ends of the upper pipe 71 and the lower pipe 72 are connected between the discharge gate 76 in the discharge pipe 73 and the discharge pump 70. An upper gate 74 is provided in the middle of the upper pipe 71, and a lower gate 75 is provided in the middle of the lower pipe 72. The fermentation residue removed from the upper discharge port 24 and the lower discharge port 25 flows through the upper pipe 71, the lower pipe 72, and the discharge pipe 73, and is sent to the dewatering machine 78. After being dewatered in the dewatering machine 78, it is effectively utilized as a raw material for compost, for example.

[0033] The return route 8 removes the fermentation residue from the intermediate outlet 26 of the methane fermentation tank 2. The return route 8 includes a return pump 80 and piping 50 consisting of an intermediate pipe 81 and a return pipe 83. One end of the return pipe 83 is connected to the return pump 80, and the other end is connected to the organic waste supply pipe 32. A return gate 86 is provided in the middle of the return pipe 83. One end of the intermediate pipe 81 is connected to the intermediate outlet 26 so that the fermentation residue can be discharged outside the tank, and the other end is connected between the return gate 86 and the return pump 80 in the return pipe 83. An intermediate gate 84 is also provided in the middle of the intermediate pipe 81. The fermentation residue removed from the intermediate outlet 26 flows through the intermediate pipe 81 and the return pipe 83 and is reintroduced into the methane fermentation tank 2 via the organic waste supply pipe 32 and the organic waste supply outlet 23.

[0034] In this embodiment, the discharge pump 70 and the return pump 80 are reciprocating pumps, and are composed of, for example, piston pumps having a piston driven for reciprocating motion, and repeatedly perform suction and discharge. The upper gate 74, lower gate 75, discharge gate 76, intermediate gate 84, and return gate 86 each include a slide gate valve and a drive actuator, the drive actuator opening and closing the slide gate valve. The control means 10 controls the flow direction and flow rate of the fermentation residue flowing through the upper piping 71, lower piping 72, discharge piping 73, intermediate piping 81, and return piping 83 by controlling the pistons of the discharge pump 70 and the return pump 80, as well as the drive actuators of the upper gate 74, lower gate 75, discharge gate 76, intermediate gate 84, and return gate 86.

[0035] The fermentation residue processing equipment 5 is equipped with various devices that are connected to the determination means 6 in a manner that allows signals to be transmitted. These devices include a temperature detection means 51, an image display 52, an audio speaker 53, a red warning lamp 54, a yellow warning lamp 55, and an injection means 56. The group indicated by the enclosed line of the symbol "Q" in Figure 1, namely the image display 52, audio speaker 53, red warning lamp 54, and yellow warning lamp 55, are provided as a single unit with computer functions (display on a screen, audio output from a built-in speaker, etc.). When each is provided as an individual device, for example, it may be installed in an electrical room, which is a room or space within a building where electrical equipment is stored. Alternatively, these devices may be combined into a management unit, and this management unit may be installed near the methane fermentation tank 2 or in the aforementioned electrical room.

[0036] <Temperature detection means> The temperature detection means 51 detects the temperature of the piping 50. In this embodiment, the temperature detection means 51 is provided in the intermediate piping 81, but it is not particularly limited to any piping 50 through which fermentation residue from the methane fermentation tank 2 flows, and the temperature detection means 51 may be provided in the upper piping 71, lower piping 72, discharge piping 73, and return piping 83. As the temperature detection means 51, for example, a temperature sensor that directly detects the outer surface temperature of the pipe 50 can be used. As the temperature sensor, one that can be attached to the outer surface of the pipe 50 is preferred, and for example, a sheet-type thermocouple formed by forming a thermocouple on an insulating sheet is suitably used. The temperature detected by the temperature detection means 51 is transmitted as raw data, or converted into temperature information by the control means 10 and transmitted to the determination means 6.

[0037] <Judgment means> The determination means 6 determines the blockage status of the pipe 50 based on the temperature or temperature information related to the temperature detected by the temperature detection means 51. The determination means 6 is a computer having a CPU, memory, and storage, and the determination function is realized by the CPU reading and executing a program recorded in the memory. Since methane fermentation is carried out at a predetermined temperature, in a steady state (when no deposit T has accumulated in the pipe 50), the temperature of the pipe 50 through which the fermentation residue from the methane fermentation tank 2 flows is detected by the temperature detection means 51 to be approximately the same temperature as the fermentation liquid in the methane fermentation tank 2. On the other hand, when deposit T accumulates in the pipe 50, the inorganic matter in the deposit T provides insulation, so the temperature of the pipe 50 gradually decreases. Also, when deposit T accumulates in the pipe 50, the temperature of the pipe 50 decreases before the internal pressure of the pipe 50 increases. Therefore, by monitoring the temperature of the pipe 50, the blockage status of the pipe 50 can be determined. The sediment removal system 1 in this configuration utilizes the phenomenon of the temperature of the pipe 50 decreasing, and includes a temperature detection means 51 for detecting the temperature of the pipe 50, and a determination means 6 for determining the blockage status of the pipe 50 based on the temperature or temperature information detected by the temperature detection means 51. Therefore, the blockage status of the pipe 50 can be detected early based on the temperature of the pipe 50. The blockage status includes a state in which sediment T has accumulated in the pipe 50 (blockage state) and a state in which no sediment T has accumulated in the pipe 50 (steady state).

[0038] Temperature information can be temperature, temperature change range, or temperature change rate. If the temperature information is temperature, the determination means 6 determines that deposits T have accumulated in the pipe 50 if the detected temperature is below a predetermined reference temperature. If the temperature information is temperature change range, the determination means 6 determines that deposits T have accumulated in the pipe 50 if the detected temperature change range (especially the temperature decrease) exceeds a certain level. If the temperature information is temperature change rate, the determination means 6 determines that deposits T have accumulated in the pipe 50 if the temperature change rate, which is the temperature change range over a certain period of time, exceeds a certain level. In this way, the blockage state of the pipe 50 can be accurately determined based on temperature information such as temperature, temperature change range, or temperature change rate.

[0039] <Notification methods> The image display unit 52 is a device that notifies the determination result of the determination means 6 by displaying an image. The voice speaker 53 is a device that notifies the determination result of the determination means 6 by voice. The red warning lamp 54 and the yellow warning lamp 55 are devices that notify the determination result of the determination means 6 by lighting up in red and yellow, respectively. The image display unit 52, the voice speaker 53, the red warning lamp 54, and the yellow warning lamp 55 all function as notification means that notify the determination result of the determination means 6. By providing notification means that notify the determination result of the determination means 6, if an abnormality occurs in the piping 50, the situation will be notified as quickly as possible by the notification means. Therefore, appropriate measures can be taken before the internal pressure of the piping 50 rises.

[0040] <Deposit removal means> The fermentation residue processing equipment 5 is equipped with a deposit removal means that removes deposits T when the determination means 6 determines that deposits T have accumulated in the pipe 50. By providing a deposit removal means that removes deposits T from the pipe 50, when deposits T accumulate in the pipe 50, the deposit removal means removes the deposits T, preventing blockage of the pipe 50.

[0041] [Switching the direction of flow] The sediment removal mechanism is implemented by switching the flow direction of the fermentation residue from forward to reverse. Because the sediment removal mechanism is implemented by switching the flow direction of the fermentation residue, there is no need to install a dedicated device for removing the sediment T, and the sediment T can be removed without human intervention.

[0042] [Discharge route] Figure 2 is a diagram illustrating the normal operation of the discharge path 7, where (a) shows the state in which fermentation residue is flowing through the upper pipe 71, (a') shows the state in which fermentation residue is flowing through the lower pipe 72, and (b) shows the state in which fermentation residue is flowing through the discharge pipe 73. Figure 3 is a diagram illustrating the reverse operation of the discharge path 7, where (a) shows the state in which fermentation residue is flowing through the discharge pipe 73, (b) shows the state in which fermentation residue is flowing through the upper pipe 71, and (b') shows the state in which fermentation residue is flowing through the lower pipe 72. In Figures 2 and 3, some parts of other components have been omitted from the illustration in order to clearly show the discharge path 7. In the schematic diagrams of the upper gate 74, lower gate 75, and discharge gate 76 shown in Figures 2 and 3, the white outline indicates the open state, and the filled-in state indicates the closed state.

[0043] Figure 2(a) shows that the upper gate 74 is open and the lower gate 75 and discharge gate 76 are closed by the control means 10. In this case, when the piston of the discharge pump 70 moves in the suction direction by the control means 10, the fermentation residue removed from the upper discharge port 24 flows through the upper piping 71 as indicated by the arrow A in Figure 2(a). Also, as shown in Figure 2(a'), when the lower gate 75 is open and the upper gate 74 and discharge gate 76 are closed by the control means 10, when the piston of the discharge pump 70 moves in the suction direction by the control means 10, the fermentation residue removed from the lower discharge port 25 flows through the lower piping 72 as indicated by the arrow A in Figure 2(a'). Figure 2(b) shows that the upper gate 74 and lower gate 75 are closed and the discharge gate 76 is open by the control means 10. In this case, when the piston of the discharge pump 70 moves in the discharge direction by the control means 10, the fermentation residue flowing through the upper pipe 71 (in the case of Figure 2(a)) or the lower pipe 72 (in the case of Figure 2(a')) flows through the discharge pipe 73 and is sent to the dewatering machine 78, as indicated by the arrow symbol B in Figure 2(b). By repeating these operations, the fermentation residue removed from the upper discharge port 24 or the lower discharge port 25 in the discharge path 7 flows through the upper pipe 71 or the lower pipe 72 and the discharge pipe 73 and is sent to the dewatering machine 78, thus completing the correct operation.

[0044] In Figure 3(a), the control means 10 closes the upper gate 74 and the lower gate 75, and opens the discharge gate 76. In this case, when the control means 10 moves the piston of the discharge pump 70 in the suction direction, it flows through the discharge pipe 73 as indicated by the arrow C in Figure 3(a). In Figure 3(b), the control means 10 opens the upper gate 74, and closes the lower gate 75 and the discharge gate 76. In this case, when the control means 10 moves the piston of the discharge pump 70 in the discharge direction, the fermentation residue flowing through the discharge pipe 73 passes through the upper gate 74 as indicated by the arrow D in Figure 3(b), and is returned to the inside of the methane fermentation tank 2 via the upper outlet 24. Furthermore, as shown in Figure 3(b'), when the control means 10 opens the lower gate 75 and closes the upper gate 74 and discharge gate 76, the control means 10 moves the piston of the discharge pump 70 in the discharge direction. As a result, the fermentation residue flowing through the discharge pipe 73 passes through the lower gate 75, as indicated by the arrow symbol D in Figure 3(b'), and is returned to the inside of the methane fermentation tank 2 via the lower discharge port 25. By repeating these operations, a reverse operation is performed in the discharge path 7, causing the fermentation residue to flow in the reverse direction towards the upper discharge port 24 or the lower discharge port 25.

[0045] Thus, in the discharge path 7, the fermentation residue removed from the upper discharge port 24 or the lower discharge port 25 flows through the upper pipe 71 or the lower pipe 72 and the discharge pipe 73 and is sent to the dewatering machine 78 (forward operation). If the determination means 6 determines that sediment T has accumulated in the upper pipe 71, the lower pipe 72, or the discharge pipe 73, an operation is performed to flow the fermentation residue in the reverse direction towards the upper discharge port 24 or the lower discharge port 25 (reverse operation). By repeating these forward and reverse operations, the sediment T can be removed.

[0046] [Return route] Figure 4 is a diagram illustrating the correct operation of the return route 8, where (a) shows the state in which fermentation residue is flowing through the intermediate pipe 81, and (b) shows the state in which fermentation residue is flowing through the return pipe 83. Figure 5 is a diagram illustrating the reverse operation of the return route 8, where (a) shows the state in which fermentation residue is flowing through the return pipe 83, and (b) shows the state in which fermentation residue is flowing through the intermediate pipe 81. In Figures 4 and 5, some other parts have been omitted from the illustration in order to clearly show the return route 8. In the schematic diagrams of the intermediate gate 84 and return gate 86 shown in Figures 4 and 5, the white state indicates the open state, and the filled state indicates the closed state.

[0047] Figure 4(a) shows that the control means 10 has opened the intermediate gate 84 and closed the return gate 86. In this case, when the control means 10 moves the piston of the return pump 80 in the suction direction, the fermentation residue removed from the intermediate discharge port 26 flows through the intermediate pipe 81 as indicated by the arrow A in Figure 4. Figure 4(b) shows that the control means 10 has closed the intermediate gate 84 and opened the return gate 86. In this case, when the control means 10 moves the piston of the return pump 80 in the discharge direction, the fermentation residue flowing through the intermediate pipe 81 flows through the return pipe 83 as indicated by the arrow B in Figure 4, and is returned to the inside of the methane fermentation tank 2 via the organic waste supply pipe 32 and the organic waste supply port 23. By repeating these operations, in the return route 8, the fermentation residue removed from the intermediate discharge port 26 flows through the intermediate pipe 81 and the return pipe 83, and is returned to the inside of the methane fermentation tank 2 via the organic waste supply pipe 32 and the organic waste supply port 23, thus completing the correct operation.

[0048] Figure 5(a) shows that the control means 10 has closed the intermediate gate 84 and opened the return gate 86. In this case, when the control means 10 moves the piston of the return pump 80 in the suction direction, it flows through the return pipe 83 as indicated by the arrow C in Figure 5. Figure 5(b) shows that the control means 10 has opened the intermediate gate 84 and closed the return gate 86. In this case, when the control means 10 moves the piston of the return pump 80 in the discharge direction, the fermentation residue flowing through the return pipe 83 flows through the intermediate pipe 81 as indicated by the arrow D in Figure 5, and is returned to the inside of the methane fermentation tank 2 via the intermediate outlet 26. By repeating these operations, a reverse operation is performed in the return path 8, causing the fermentation residue to flow in the reverse direction toward the intermediate outlet 26.

[0049] Thus, in the return route 8, the fermentation residue removed from the intermediate discharge port 26 flows through the intermediate pipe 81 and the return pipe 83 and is returned to the inside of the methane fermentation tank 2 via the organic waste supply pipe 32 and the organic waste supply port 23 (forward operation). If the determination means 6 determines that sediment T has accumulated in the intermediate pipe 81 or the return pipe 83, an operation is performed to flow the fermentation residue in the reverse direction toward the intermediate discharge port 26 (reverse operation). By repeating these forward and reverse operations, the sediment T can be removed.

[0050] [Injection means] As an alternative to switching the flow direction, a means of removing sediment can also be provided, which involves injecting a high-pressure fluid into the sediment T to remove it. Figure 6 is an explanatory diagram of the injection means 56. As shown in the enlarged cross-sectional view of part A in Figure 6, sediment T tends to accumulate in the vent pipe in particular within the piping 50. By installing the temperature detection means 51 at the bottom of the piping 50 where sediment is likely to accumulate, blockage of the piping 50 can be detected early based on the temperature information of the piping 50, even in bent sections where sediment T is particularly likely to accumulate. The injection means 56 comprises a high-pressure fluid injection pipe 57, an on-off valve 58, and a high-pressure fluid pump 59. As shown in Figure 6, the high-pressure fluid injection pipe 57 is fixed to a part where sediment T is likely to accumulate and is configured to inject high-pressure fluid into the sediment T. The on-off valve 58 is, for example, an electromagnetic on-off valve, and the control means 10 controls the on-off valve 58 so that the high-pressure fluid pumped from the high-pressure fluid pump 59 is injected from the high-pressure fluid injection pipe 57. Examples of high-pressure fluids injected from the high-pressure fluid injection pipe 57 include compressed air, pressurized water, and nitrogen. Since the sediment removal means is an injection means 56 that injects high-pressure fluid, the sediment T can be directly loosened, and the sediment T can be removed more reliably. The injection of high-pressure fluid into the sediment T by the injection means 56 may be performed simultaneously with the switching of the flow direction of the fermentation residue.

[0051] <Control means> The control means 10 is a computer having a CPU, memory, storage, etc., and it has the function of controlling the operations of the fermentation residue processing equipment 5 and the determination means 6 by having the CPU read and execute a program recorded in the memory. The operations of the fermentation residue processing equipment 5 and the determination means 6 are as described above. In addition, the control means 10 converts the temperature detected by the temperature detection means 51 into temperature information.

[0052] [Deposit removal method] Figure 7 is a flowchart showing the procedure for the sediment removal method of the present invention. In the sediment removal method of the present invention, the temperature detection step and the determination step are executed sequentially using the methane fermentation facility 100 shown in Figure 1, and optionally the notification step and the sediment removal step are also executed. In the flowchart of Figure 7, each step of the sediment removal method is indicated by the symbol "S".

[0053] <Temperature detection process: S1> In the temperature detection process, the temperature of the piping 50 is detected by the temperature detection means 51. The temperature detected by the temperature detection means 51 is transmitted either as raw data or converted into temperature information by the control means 10 and sent to the determination means 6.

[0054] <Judgment process / Notification process: S2~S3> In the determination step, the determination means 6 determines the blockage status of the pipe 50 based on the temperature or temperature information related to the temperature detected by the temperature detection means 51. For example, if the detected temperature is below a predetermined reference temperature, it can be determined that deposits T have accumulated in the pipe 50. If it is determined that deposits T have accumulated in the pipe 50 (S2: YES), the notification means notifies that deposits T have accumulated in the pipe 50 (S3), and the process proceeds to the deposit removal step (S4). If it is determined that deposits T have not accumulated in the pipe 50 (S2: NO), the process ends. If it is determined that deposits T have not accumulated in the pipe 50 (S2: NO), the system may actively notify that deposits T have not accumulated in the pipe 50, for example, by displaying "Normal" on the image display 52.

[0055] <Deposit removal process: S4> In the sediment removal process, the control means 10 switches the flow direction of the fermentation residue and / or the injection means 56 injects high-pressure fluid into the sediment T to remove the sediment T from the piping 50. The switching of the flow direction of the fermentation residue by the control means 10 and the injection of high-pressure fluid into the sediment T by the injection means 56 may be performed simultaneously. For example, by simultaneously injecting high-pressure fluid into the sediment T by the injection means 56 while the reverse operation is being performed, the sediment T can be removed more reliably. Once the sediment T is removed, the process is terminated.

[0056] As described above, in the sediment removal system and sediment removal method of the present invention, the blockage status of the pipe 50 is determined based on the temperature or temperature-related temperature information detected by the temperature detection means 51, making it possible to detect the blockage of the pipe 50 early, before the internal pressure of the pipe 50 rises. [Industrial applicability]

[0057] The sediment removal system of the present invention can be used, for example, to remove sediment generated in conjunction with the passage of fermentation residue in methane fermentation facilities. [Explanation of Symbols]

[0058] 1. Sediment removal system 2. Methane fermentation tank 6 Judgment means 50 Piping 51 Temperature detection means 52 Image display (notification means) 53. Audio speaker (notification means) 54. Red warning lamp (notification method) 55. Yellow warning light (notification method) 56 Injection means (deposit removal means) T deposit

Claims

1. A sediment removal system for removing sediment accumulated in pipes through which fermentation residue from a methane fermentation tank flows, A temperature detection means for detecting the temperature of the aforementioned pipe, A determination means for determining the blockage status of the piping based on the temperature or temperature information related to the temperature detected by the temperature detection means, A sediment removal system equipped with the following features.

2. The sediment removal system according to claim 1, further comprising a notification means for notifying the determination result of the determination means.

3. The sediment removal system according to claim 1, further comprising means for removing sediment from the aforementioned pipe.

4. The sediment removal system according to claim 3, wherein the sediment removal means is achieved by switching the flow direction of the fermentation residue.

5. The sediment removal system according to claim 3, wherein the sediment removal means is an injection means for injecting a high-pressure fluid.

6. The sediment removal system according to any one of claims 1 to 5, wherein the temperature information is temperature, temperature change range, or temperature change rate.

7. The sediment removal system according to any one of claims 1 to 5, wherein the piping is a vent pipe.

8. A method for removing sediment accumulated in a pipe through which fermentation residue from a methane fermentation tank flows, A temperature detection step for detecting the temperature of the aforementioned pipe, A determination step that determines the blockage status of the piping based on the temperature or temperature information related to the temperature detected by the temperature detection step, A sediment removal method encompassing [the following].

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