Composting apparatus

Abstract

To reduce the cost and improve the efficiency of compost production in a compost production apparatus.SOLUTION: The compost manufacturing apparatus 1 includes a plurality of tanks 10 for storing a compost raw material M, a tank rotation device 30 having a rotation mechanism part 33 for rotating one tank 10 among the plurality of tanks 10, and a control device 40 for controlling the tank rotation device 30. The tank rotation device 30 further includes a movement mechanism part 31 that moves the rotation mechanism part 33. The control device 40 controls the movement mechanism part 31 to move the rotation mechanism part 33 to a position corresponding to one tank 10.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a composting apparatus. [Background technology]

[0002] Patent Document 1 discloses, as an example of a compost production apparatus, a fermentation tank apparatus having a can body that contains fermentation materials and a roller mechanism that rotates the can body. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-182898 Summary of the Invention [Problem to be solved by the invention]

[0004] There is a demand for compost production equipment that is both cost-effective and efficient in producing compost.

[0005] An aspect of the present disclosure aims to reduce costs and improve the efficiency of compost production in a compost production apparatus. [Means for solving the problem]

[0006] An aspect of the present disclosure is a compost production apparatus comprising a plurality of tanks for storing raw materials for compost, a tank rotation device having a rotation mechanism for rotating one of the plurality of tanks, and a control device for controlling the tank rotation device, wherein the tank rotation device further comprises a movement mechanism for moving the rotation mechanism, and the control device controls the movement mechanism to move the rotation mechanism to a position corresponding to one of the tanks.

[0007] According to an aspect of the present disclosure, the rotation mechanism rotates one of the multiple tanks. This reduces the number of parts required for the rotation mechanism compared to when the rotation mechanism simultaneously drives multiple tanks. This reduces the cost of the compost production device. Furthermore, compost can be produced using multiple tanks, and the multiple tanks can be rotated at different times. This allows for efficient production of compost.

[0008] In an aspect of the present disclosure, each of the multiple tanks has an opening for discharging the compost, the tank rotation device further has a tilting mechanism that tilts one of the tanks in a direction so that the opening faces downward, and the control device controls the tilting mechanism to tilt the one of the tanks and controls the rotation mechanism to rotate the one of the tanks, thereby discharging the compost from the opening.

[0009] In this system, the control device tilts and rotates the tank, causing the compost to be discharged from the opening of the tank. This allows the compost to be efficiently discharged from the opening without having a discharge mechanism inside the tank, thereby reducing the cost of the compost production device.

[0010] In an aspect of the present disclosure, the rotation mechanism includes a drive roller and a driven roller that contact the outer peripheral surface of the one tank and rotate the one tank around the rotation axis of the one tank, and when the tank rotation device is viewed along the rotation axis with the drive roller and the driven roller in contact with the one tank, a first angle formed by a first imaginary line connecting a first contact point between the drive roller and the outer peripheral surface and the rotation axis and a vertical line passing through the rotation axis is smaller than a second angle formed by a second imaginary line connecting a second contact point between the driven roller and the outer peripheral surface and the rotation axis and the vertical line.

[0011] According to this, the weight of the tank acting on the drive roller is greater than the weight of the tank acting on the driven roller. Therefore, in this case, the drive roller can rotate the tank more efficiently than when the weight of the tank acting on the drive roller and the weight of the tank acting on the driven roller are equal. Furthermore, when one tank is rotated by a drive roller and a driven roller, the number of parts in the tank rotation device can be reduced compared to when the tank is rotated by two drive rollers, thereby reducing the cost of the compost production apparatus.

[0012] In an aspect of the present disclosure, when the tank rotation device is viewed along the rotation axis with the drive roller and driven roller in contact with the one tank, the first angle and the second angle are set to values ​​at which the center of gravity of the one tank moves horizontally between the first contact point and the second contact point.

[0013] This allows the center of gravity of the tank to move between the first and second contact points that support the tank in the horizontal direction, thereby stabilizing the rotation of the tank.

[0014] In an aspect of the present disclosure, the rotation mechanism rotates the one tank by frictional force generated between the outer circumferential surface and the drive roller.

[0015] According to this, when the weight of the tank acting on the drive roller is greater than the weight of the tank acting on the driven roller, the frictional force is greater than when the weights of the tank acting on the drive roller and the driven roller are equal, thereby stabilizing the rotation of the tank.

[0016] In an embodiment of the present disclosure, the composting system further includes an air supply device that supplies air to the one tank and a carbon dioxide concentration sensor that detects the concentration of carbon dioxide discharged from the one tank, wherein the raw material contains organic matter, and the control device calculates the total amount of carbon dioxide produced by microorganisms decomposing the organic matter based on the detection value of the carbon dioxide concentration sensor, and determines that the compost is complete if the total amount is equal to or greater than a predetermined total amount judgment value.

[0017] Microorganisms are decomposers that break down the organic matter contained in the raw materials inside the tank, and they maintain their life using oxygen from the air inside the tank. In other words, the microorganisms are activated by the air supplied into the tank and break down the organic matter. When the organic matter is decomposed, the temperature of the raw material rises above room temperature. When the organic matter is decomposed by the microorganisms, carbon dioxide is produced. Conventionally, the determination of whether or not compost is complete has been based on, for example, the feel of the composted raw materials, and is based on the manufacturer's experience, etc. Therefore, the determination of whether or not compost is complete may not be performed appropriately. In contrast, in the present disclosure, the determination of whether compost is complete is based on the total amount of carbon dioxide produced by the decomposition of organic matter by microorganisms. As the decomposition of organic matter progresses, the total amount of carbon dioxide increases. Therefore, by predetermining the total amount of carbon dioxide when compost is complete as a predetermined total amount determination value, it is possible to appropriately determine whether compost is complete.

[0018] In an aspect of the present disclosure, the organic matter contains fiber that can be used as fertilizer, and protein that can be used as fertilizer and has a faster rate of microbial decomposition than the fiber, and the predetermined total amount judgment value corresponds to the total amount corresponding to the raw material that has a protein content lower than the content at which the protein effectively functions as fertilizer and a fiber content at which the fiber effectively functions as fertilizer.

[0019] This allows for the appropriate production of so-called fully matured compost, which is compost containing fibrous material that can be used as fertilizer.

[0020] In an aspect of the present disclosure, the organic matter includes fiber that can be used as fertilizer, protein that can be used as fertilizer and that is decomposed by microorganisms at a faster rate than the fiber, and decomposition products that can be used as fertilizer when their content is equal to or less than a predetermined content and that are decomposed by microorganisms at a faster rate than the protein, and the predetermined total amount judgment value corresponds to the total amount corresponding to the raw material having a protein content and a fiber content that allow the protein and fiber to function effectively as fertilizer and whose content of decomposition products is equal to or less than the predetermined content.

[0021] This allows for the appropriate production of so-called semi-mature compost, which is compost containing protein and fiber that can be used as fertilizer.

[0022] In an aspect of the present disclosure, the control device controls the air supply device based on the detected value of the carbon dioxide concentration sensor to adjust the amount of air supplied.

[0023] This makes it possible to stabilize and therefore improve the efficiency of decomposition of raw materials by microorganisms.

[0024] Another aspect of the present disclosure is a compost manufacturing apparatus comprising: a tank for storing compost raw materials; a tank rotation device having a rotation mechanism for rotating the tank; and a control device for controlling the tank rotation device, wherein the rotation mechanism comprises a drive roller and a driven roller that contact the outer peripheral surface of the tank and rotate the tank around the rotation axis of the tank; and when the tank rotation device is viewed along the rotation axis with the drive roller and the driven roller in contact with the tank, a first angle formed by a first imaginary line connecting a first contact point between the drive roller and the outer peripheral surface and the rotation axis and a vertical line passing through the rotation axis is smaller than a second angle formed by a second imaginary line connecting a second contact point between the driven roller and the outer peripheral surface and the rotation axis and the vertical line.

[0025] According to this, the weight of the tank acting on the drive roller is greater than the weight of the tank acting on the driven roller. Therefore, in this case, the drive roller can rotate the tank more efficiently than when the weight of the tank acting on the drive roller and the weight of the tank acting on the driven roller are equal. Furthermore, when the tank is rotated by the drive roller and the driven roller, the number of parts in the tank rotation device can be reduced compared to when the tank is rotated by two drive rollers, and the cost of the compost production apparatus can be reduced. [Effects of the Invention]

[0026] According to the aspects of the present disclosure, it is possible to improve the efficiency of compost production in a compost production apparatus and reduce the cost of the apparatus. [Brief explanation of the drawings]

[0027] [Figure 1] FIG. 1 is a front view of the composting apparatus. [Figure 2] FIG. 2 is a partial cross-sectional view of the composting apparatus. [Figure 3] FIG. 3 is a front view of the tank and the tank rotation device. [Figure 4] FIG. 4 is a side view of the tank and the tank rotation device, showing a state in which the tank is tilted by the tilting mechanism. [Figure 5] FIG. 5 is a schematic diagram showing the configuration of the air intake device and the exhaust device. [Figure 6] FIG. 6 is a block diagram of a composting apparatus. [Figure 7] FIG. 7 is a diagram showing the relationship between the content of substances contained in raw materials and the time required to produce compost. [Figure 8] FIG. 8 is a diagram showing the relationship between the flow rate per unit time of carbon dioxide discharged from the tank and the compost production time. [Figure 9] FIG. 9 is a flowchart showing the process executed by the control device in producing compost. [Figure 10] FIG. 10 is a diagram showing the relationship between the flow rate of carbon dioxide per unit time and the test time in the preliminary test. [Figure 11] FIG. 11 is a diagram showing the relationship between the total amount of carbon dioxide and the test time in the preliminary test. [Figure 12] FIG. 12 is a schematic diagram showing the configuration of an exhaust device according to a first modified example of this embodiment. [Figure 13] FIG. 13 is a flowchart executed by the control device of the compost production apparatus according to the first modified embodiment of the present disclosure. [Figure 14] FIG. 14 is a front view of a tank and a tank rotation device according to a fourth modified example of the embodiment of the present disclosure. [Figure 15] FIG. 15 is a schematic diagram showing the configuration of a tank, an air supply device, and an exhaust device according to another modified example of the embodiment of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0028] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings, but the present disclosure is not limited thereto. The components of each embodiment and each modified example described below can be combined as appropriate. In addition, some components may not be used.

[0029] In the following description, the width direction of the compost production apparatus 1 is referred to as the X direction, the depth direction of the compost production apparatus 1 as the Y direction, and the height direction (vertical direction) of the compost production apparatus 1 as the Z direction. The X direction, Y direction, and Z direction are perpendicular to each other. Note that the X, Y, and Z directions are merely examples, and the present disclosure is not limited to these directions.

[0030] FIG. 1 is a front view of a compost production apparatus 1. FIG. 2 is a partial cross-sectional view of the compost production apparatus 1. The compost production apparatus 1 produces compost by decomposing a raw material M shown in FIG. 2 using microorganisms. The raw material M contains organic matter, which will be described later. The raw material M is made up of, for example, livestock manure and sawdust. The organic matter is contained in the livestock manure and sawdust. It goes without saying that the composition of the raw material M is not limited to livestock manure and sawdust.

[0031] The microorganisms are aerobic microorganisms that are activated by oxygen in the air. The microorganisms may include not only aerobic microorganisms but also anaerobic microorganisms. Aerobic microorganisms decompose raw material M faster than anaerobic microorganisms, and do not produce carboxylic acids that produce a foul odor or methane gas, which has a relatively high greenhouse effect, when decomposing raw material M.

[0032] As shown in FIGS. 1 and 2, the compost production apparatus 1 includes a plurality of tanks 10, a support 20, a tank rotation device 30, and a control device 40.

[0033] As shown in FIG. 2, the tank 10 contains raw materials M for compost. The tank 10 has a hollow cylindrical shape. The tank 10 is arranged with its central axis Lc aligned along the Y direction. The total volume of the raw materials M contained in the tank 10 corresponds to approximately half the capacity of the tank 10. The total weight of the raw materials M contained in the tank 10 is, for example, 1,000 kg.

[0034] A first groove portion 11 and a second groove portion 12, each having a U-shaped cross section, are arranged around the entire outer periphery of the outer surface of the tank 10. The first groove portion 11 is arranged on the -Y side of the center of the tank 10. The second groove portion 12 is arranged on the +Y side of the center of the tank 10.

[0035] Additionally, first side wall 13 on the -Y side of tank 10 has opening 13a for discharging compost. During compost production, a lid member (not shown) that closes opening 13a is attached to opening 13a.

[0036] As shown in Fig. 1, the plurality of tanks 10 are arranged in parallel along the X direction. Although the number of tanks 10 shown in Fig. 1 is four, it goes without saying that the number is not limited to four.

[0037] The support 20 supports the plurality of tanks 10. The support 20 supports the plurality of tanks 10 so that the tank rotation device 30 can move below the plurality of tanks 10. As shown in FIG. 2 , the support 20 supports the outer circumferential surfaces of the tanks 10 on both sides of the first groove portion 11 and the second groove portion 12 in the Y direction. As will be described later, the tank 10 is lifted by the tank rotation device 30 and moves away from the support 20.

[0038] The tank rotation device 30 rotates one of the multiple tanks 10. As shown in FIGS. 1 and 2, the tank rotation device 30 has a movement mechanism 31, a lifting mechanism 32, a rotation mechanism 33, and a tilting mechanism 34.

[0039] The movement mechanism 31 moves the tank rotation device 30. The movement mechanism 31 has a first base 31a, a plurality of wheels 31b, and a first drive device 31c that drives at least one wheel 31b.

[0040] The multiple wheels 31b are attached to the first base 31a and fit into a pair of rails R arranged along the X direction on the installation surface of the compost production apparatus 1. The first drive device 31c is, for example, an electric motor, and is controlled by the control device 40. The power of the first drive device 31c is transmitted to one wheel 31b by, for example, a belt (not shown). When the first drive device 31c is driven, the tank rotation device 30 moves along the X direction.

[0041] The compost production apparatus 1 further includes a position sensor (not shown) that detects the position of the tank rotation device 30. The position sensor is, for example, an infrared sensor, and a plurality of position sensors are arranged, for example, on the support body 20. When the tank rotation device 30 is positioned at a position corresponding to one of the plurality of tanks 10, the position sensor transmits a detection signal to that effect to the control device 40. The position corresponding to one tank 10 is the position at which the tank rotation device 30 rotates one tank 10. The position sensor may also be a limit switch.

[0042] In this way, the control device 40 controls the first driving device 31c based on the detection signal of the position sensor, thereby adjusting the position of the tank rotation device 30. In other words, the control device 40 controls the movement mechanism 31 to move the rotation mechanism 33 to a position corresponding to one tank 10.

[0043] The lifting mechanism 32 is disposed on the first base 31a of the moving mechanism 31, supports the rotation mechanism 33, and raises and lowers the rotation mechanism 33. Specifically, the lifting mechanism 32 raises and lowers the rotation mechanism 33 between a retracted position Po1, where the rotation mechanism 33 is not in contact with the tank 10, and a rotation position Po2, which is located above the retracted position Po1 and where the rotation mechanism 33 comes into contact with the tank 10 and rotates the tank 10 as described below. The position of the rotation mechanism 33 shown in FIGS. 1 and 2 is the retracted position Po1.

[0044] FIG. 3 is a front view of the tank 10 and the tank rotation device 30. The support 20 and the pair of rails R are omitted from FIG. 3. The position of the rotation mechanism 33 shown in FIG. 3 is rotation position Po2. When the rotation mechanism 33 is located at rotation position Po2, the tank 10 is lifted by the rotation mechanism 33, and the tank 10 moves away from the support 20.

[0045] Specifically, the lifting mechanism 32 includes a plurality of first linear actuators 32a that move the rotation mechanism 33 in the Z direction. Upper ends of the plurality of first linear actuators 32a are connected to the rotation mechanism 33. The first linear actuators 32a are, for example, electric screw jacks. Note that the first linear actuators 32a may also be hydraulic cylinders, electric linear actuators, or the like.

[0046] The rotation mechanism 33 rotates one tank 10. As shown in Figures 2 and 3, the rotation mechanism 33 includes a second base 33a, two pairs of rollers 33b, and a second drive device 33c. The second base 33a is supported by the lifting mechanism 32.

[0047] The two pairs of rollers 33b are arranged on the second base 33a, and are spaced apart from the tank 10 when the rotation mechanism 33 is in the retracted position Po1 as shown in FIG. 2, and are in contact with the outer circumferential surface of the tank 10 when the rotation mechanism 33 is in the rotation position Po2 as shown in FIG. 3. Specifically, one pair of rollers 33b shown in FIG. 3 fits into the first groove 11. The other pair of rollers 33b fits into the second groove 12. The bottom surfaces of the first groove 11 and the second groove 12 correspond to part of the outer circumferential surface of the tank 10.

[0048] Each of the two pairs of rollers 33b includes a drive roller 33b1 and a driven roller 33b2. As shown in FIG. 3, when the rotation mechanism 33 is located at a rotation position Po2 and the drive roller 33b1 rotates, the tank 10 rotates around the central axis Lc. The central axis Lc of the tank 10 corresponds to the rotation axis. Specifically, the tank 10 rotates around the central axis Lc due to frictional force generated between the outer circumferential surface of the drive roller 33b1 and the outer circumferential surface of the tank 10.

[0049] The second driving device 33c rotates the driving roller 33b1. The second driving device 33c is, for example, an electric motor, and the power of the second driving device 33c is transmitted to the driving roller 33b1 via a belt 33d.

[0050] Furthermore, when the rotation mechanism 33 is positioned at the rotation position Po2 and the tank rotation device 30 is viewed along the central axis Lc, the first angle θ1 formed by the first virtual line L1 connecting the first contact point Pt1 between the drive roller 33b1 and the outer peripheral surface of the tank 10 and the central axis Lc, and the vertical line Lv passing through the central axis Lc, is smaller than the second angle θ2 formed by the second virtual line L2 connecting the second contact point Pt2 between the driven roller 33b2 and the outer peripheral surface and the central axis Lc, and the vertical line Lv.

[0051] The first angle θ1 and the second angle θ2 are angles at which the tank 10 containing the raw material M can rotate stably without tipping over. When the tank 10 rotates, the raw material M is agitated, and the center of gravity of the tank 10 containing the raw material M moves. Therefore, the first angle θ1 and the second angle θ2 are set to values ​​at which the center of gravity of the tank 10 moves between the first contact point Pt1 and the second contact point Pt2 in the horizontal direction (corresponding to the X direction in this embodiment) when the tank rotation device 30 is viewed along the central axis Lc. The first angle θ1 and the second angle θ2 are determined based on experiments or the like that are performed in advance.

[0052] The tilting mechanism 34 tilts the tank 10 in a direction such that the opening 13a faces downward. The tilting mechanism 34 is disposed on the first base 31a, supports the rotation mechanism 33, and tilts the rotation mechanism 33. An upper end of the tilting mechanism 34 is connected to the tilting mechanism 34 so that the rotation mechanism 33 can be tilted relative to the tilting mechanism 34. The tilting mechanism 34 tilts the rotation mechanism 33 when the rotation mechanism 33 is located at the rotation position Po2.

[0053] Specifically, the tilting mechanism 34 includes a plurality of second linear actuators 34a that move the rotation mechanism 33 in the Z direction. The second linear actuators 34a are, for example, electric screw jacks. The second linear actuators 34a may also be hydraulic cylinders, electric linear actuators, or the like.

[0054] The plurality of second linear actuators 34a include a front actuator 34b that supports the −Y side of the first groove portion 11, and a rear actuator 34c that supports the +Y side of the second groove portion 12.

[0055] 4 is a side view of the tank 10 and the tank rotation device 30, showing a state in which the tank 10 is tilted by the tilting mechanism 34. When the rotation mechanism 33 is located at rotation position Po2, the rear actuator 34c extends, causing the rotation mechanism 33 and the tank 10, which is lifted by the rotation mechanism 33, to tilt in a direction in which the opening 13a faces downward. At this time, two pairs of rollers 33b are fitted into the first groove 11 and the second groove 12.

[0056] The lifting mechanism 32 may tilt the tank 10 together with the tilting mechanism 34 by connecting the rotation mechanism 33 to the upper end of the lifting mechanism 32 so that the rotation mechanism 33 can tilt relative to the lifting mechanism 32. In this case, since the lifting mechanism 32 has a mechanism for tilting the tank 10, the tank rotation device 30 does not need to be equipped with the tilting mechanism 34. Furthermore, when the tank rotation device 30 has the tilting mechanism 34 as described above, the tilting mechanism 34 may raise and lower the rotation mechanism 33 together with the lifting mechanism 32.

[0057] The compost production apparatus 1 also includes an air supply device 50 and an exhaust device 60. Figure 5 is a schematic diagram showing the configuration of the air supply device 50 and the exhaust device 60. Figure 6 is a block diagram of the compost production apparatus 1. The air supply device 50 includes an air blower 51, an air supply pipe 52, an air blowout pipe 53, a flow rate adjustment valve 54, and a flow rate sensor 55.

[0058] Air blower 51 is disposed outside tank 10 and is connected to air blowing pipe 53 via air intake pipe 52. Air blower 51 draws in air (outside air) and supplies the air to air intake pipe 52 and air blowing pipe 53. The driving amount of air blower 51 is adjusted by control device 40.

[0059] The air blowing pipe 53 is disposed inside the tank 10 and has a plurality of blowing ports 53a for blowing out air. When the rotation of the tank 10 is stopped, the air blowing pipe 53 is located at the bottom of the tank 10 and is covered with the raw material M.

[0060] Furthermore, the air blowout pipe 53 and the air supply pipe 52 are connected to the tank 10 via a first joint 10a disposed on the second side wall 14 on the +Y side of the tank 10, so that the air supply pipe 52 can rotate relative to the air blowout pipe 53 and the tank 10. Furthermore, the first joint 10a detachably connects the air blowout pipe 53 and the air supply pipe 52.

[0061] The flow rate adjustment valve 54 adjusts the flow rate of air flowing through the air intake pipe 52. The flow rate adjustment valve 54 is an electrically operated flow rate adjustment valve, and has, for example, a throttle valve (not shown) that adjusts the air flow area and an actuator (not shown) that drives the throttle valve. The flow rate adjustment valve 54 is controlled by the control device 40, and the flow rate of air flowing through the air intake pipe 52 (flow rate per unit time (unit: m 3 / min); same below) is adjusted.

[0062] The flow rate sensor 55 detects the flow rate of air flowing through the air supply pipe 52. The detected value of the flow rate sensor 55 is sent to the control device 40.

[0063] The exhaust device 60 includes an exhaust pipe 61, a dryer 62, a carbon dioxide concentration sensor 63, and a first temperature sensor 64. The dryer 62, the carbon dioxide concentration sensor 63, and the first temperature sensor 64 are arranged in the exhaust pipe 61.

[0064] The exhaust pipe 61 exhausts air from the tank 10. When the rotation of the tank 10 is stopped, a first end of the exhaust pipe 61 is located at the upper part of the tank 10, above the raw material M. The exhaust pipe 61 and the tank 10 are connected to each other by a second joint 10b disposed on the second side wall 14, so that the exhaust pipe 61 can rotate relative to the tank 10. The second joint 10b further detachably connects the tank 10 and the exhaust pipe 61. A second end of the exhaust pipe 61 is located outside the tank 10.

[0065] The dryer 62 removes moisture from the air flowing through the exhaust pipe 61 .

[0066] The carbon dioxide concentration sensor 63 (hereinafter, may be referred to as the CO2 sensor 63) detects the concentration of carbon dioxide discharged from the tank 10. Specifically, the CO2 sensor 63 detects the concentration of carbon dioxide contained in the air flowing through the exhaust pipe 61. The concentration of carbon dioxide is expressed as, for example, a molar concentration (unit: mol / m 3 ) is shown.

[0067] The CO2 sensor 63 is, for example, an NDIR (Non Dispersive Infrared) type sensor including a light source and an infrared sensor. The CO2 sensor 63 may also be an MOX (Metal Oxide) type sensor including a metal oxide in the detection unit. The detection value of the CO2 sensor 63 is transmitted to the control device 40.

[0068] The first temperature sensor 64 detects the temperature of the air flowing through the exhaust pipe 61. The detected value of the first temperature sensor 64 is sent to the control device 40.

[0069] The compost production apparatus 1 further includes a second temperature sensor 70 that is disposed inside the tank 10 and measures the temperature of the raw material M. The detected value of the second temperature sensor 70 is sent to the control device 40.

[0070] The control device 40 shown in Figures 1 and 6 controls the compost production apparatus 1. The control device 40 includes an input unit (not shown; for example, a keyboard) and a display unit (not shown). The control of the compost production apparatus 1 carried out by the control device 40 will be described in detail below.

[0071] Next, we will explain the changes that occur in raw material M during the compost production process. Figure 7 is a diagram showing the relationship between the content of substances contained in raw material M and the compost production time. The organic matter contained in raw material M includes substances such as sugar, starch, protein, and fiber.

[0072] Sugars and starch are decomposition products that can be used as fertilizer when their content in raw material M is equal to or less than a predetermined content. Raw material M with sugar and starch contents greater than the predetermined content inhibits, for example, plant root growth when used as fertilizer. The predetermined content is derived through experiments or the like performed in advance.

[0073] Protein and fiber can be used as fertilizer. When protein is used as fertilizer, it functions as a fertilizer by being decomposed into amino acids, ammonia, and nitrate in that order. However, if the protein and fiber content is relatively low, the protein and fiber do not function effectively as fertilizer.

[0074] As the decomposition of raw material M by microorganisms progresses, the organic substances sugar, starch, protein, and fiber are decomposed by the microorganisms, and the starch, protein, and fiber content gradually decreases. Sugar and starch are decomposed faster by microorganisms than protein. Protein is also decomposed faster by microorganisms than fiber. In other words, of the decomposition rates of sugar, starch, protein, and fiber, fiber decomposes at the slowest rate.

[0075] Raw material M that has not been decomposed to a sufficient extent and has a sugar and starch content greater than a predetermined content cannot be used appropriately as fertilizer and corresponds to what is called immature compost.

[0076] When the decomposition of raw material M progresses and the sugar and starch content is below a specified content, the protein content is such that the protein functions effectively as a fertilizer (approximately 60% or more), and the fiber content is such that the fiber functions effectively as a fertilizer (approximately 80% or more), raw material M can be appropriately used as a fertilizer and corresponds to what is known as semi-mature compost.

[0077] Furthermore, as the decomposition of raw material M progresses, raw material M that has a lower protein content than the content at which protein functions effectively as fertilizer and a fiber content at which fiber functions effectively as fertilizer can be used appropriately as fertilizer and corresponds to so-called fully matured compost.

[0078] Furthermore, carbon dioxide is produced when organic matter (sugars, starch, protein, and fiber) is decomposed. As shown in Figure 7, organic matter is decomposed throughout the entire compost production time. In other words, carbon dioxide is produced throughout the entire compost production time.

[0079] Next, the compost production process will be described. Figure 8 shows the relationship between the flow rate per unit time of carbon dioxide discharged from tank 10 and the compost production time. Note that the relationship between the flow rate per unit time of carbon dioxide and the compost production time in this embodiment is shown by a solid line.

[0080] First, raw material M is charged into tank 10, and with rotation of tank 10 stopped, air is supplied into tank 10 from air outlet pipe 53 (time t0). As a result, the air inside tank 10 is exhausted through exhaust pipe 61. By supplying air into tank 10, microorganisms inside tank 10 are activated, and decomposition of raw material M begins. Decomposition of raw material M progresses in the center of raw material M, which has better heat retention than the peripheral portion of raw material M.

[0081] The flow rate of air supplied to the tank 10 is substantially constant at a rate that prevents oxygen deficiency in the microorganisms and prevents a decrease in the temperature of the raw material M due to the supply of air, and is determined in advance through experiments, etc. The control device 40 may perform feedback control to adjust the drive amount of the air blower 51 and the operation amount of the throttle valve of the flow rate adjustment valve 54 based on the deviation between the target flow rate and the detection value of the flow rate sensor 55, for example.

[0082] As the decomposition of the raw material M progresses, the flow rate of carbon dioxide discharged from the tank 10 (flow rate per unit time (unit: m 3 / min; the same below) begins to increase (time t1). As the decomposition of raw material M progresses, the flow rate of carbon dioxide begins to decrease (time t2).

[0083] The control device 40 also rotates the tank 10 at predetermined first time intervals T from the start of compost production. Specifically, with the rotation mechanism 33 in the retracted position Po1, the control device 40 controls the movement mechanism 31 to move the rotation mechanism 33 to a position corresponding to a desired tank 10. Furthermore, the control device 40 controls the lifting mechanism 32 to move the rotation mechanism 33 to the rotation position Po2. As a result, the two pairs of rollers 33b fit into the first groove 11 and the second groove 12 and come into contact with the outer circumferential surface of the tank 10 (FIG. 3).

[0084] Furthermore, the control device 40 controls the second drive device 33c to rotate the drive roller 33b1, the tank 10, and the driven roller 33b2. This agitates the raw material M in the tank 10, mixing the portions of the raw material M that are relatively decomposed with the portions of the raw material M that are relatively less decomposed. The control device 40 rotates the tank 10 for a second predetermined time T that is shorter than the first predetermined time T. The second predetermined time T is set to a time (e.g., 10 minutes) that allows the degree of decomposition of the raw material M to become uniform.

[0085] While the tank 10 is rotating, the control device 40 may continue or stop the supply of air into the tank 10. When the supply of air into the tank 10 is stopped, the air supply pipe 52 and the exhaust pipe 61 may be removed from the tank 10.

[0086] When the rotation of the tank 10 stops, the progress of decomposition of the raw material M becomes uniform. Then, air is supplied into the tank 10, and the decomposition of the raw material M resumes, increasing the flow rate of carbon dioxide (time t3).

[0087] The first predetermined time T is, for example, 24 hours, and is set to a time longer than the time it takes for the flow rate of carbon dioxide to increase and decrease after several (for example, two) rotations of the tank 10. The first predetermined time T and the second predetermined time are stored in advance in the control device 40.

[0088] In this way, the raw material M is decomposed in the center of the raw material M, and the repeated rotation of the tank 10 progresses the decomposition of the entire raw material M. As the decomposition of the entire raw material M progresses, the flow rate of carbon dioxide gradually decreases while repeatedly increasing and decreasing, and the production of compost is completed (time t4).

[0089] Furthermore, when raw material M is decomposing, the temperature of raw material M rises compared to when raw material M is not decomposed. Furthermore, during the compost production process, the temperature of raw material M increases and decreases at roughly the same time as the increase and decrease in the flow rate of carbon dioxide. From the early to middle stages of the compost production process, when the decomposition of raw material M is progressing efficiently and the flow rate of carbon dioxide is relatively high, the temperature of raw material M is between approximately 60°C and 70°C. As the decomposition of raw material M progresses, the efficiency of decomposition decreases, and at the end of the compost production process, when the flow rate of carbon dioxide decreases, the temperature of raw material M is approximately 50°C.

[0090] Compost may be produced at the same time in multiple tanks 10. Alternatively, compost may be produced at different times in multiple tanks 10. In this case, the multiple tanks 10 are rotated at different times.

[0091] Next, a description will be given of the control executed by the control device 40 in the production of compost. Figure 9 is a flowchart showing the control executed by the control device 40 in the production of compost.

[0092] In step S1, the control device 40 acquires the detection value of the CO2 sensor 63 and the detection value of the flow sensor 55. The detection value of the flow sensor 55 corresponds to the flow rate of air flowing through the exhaust pipe 61.

[0093] Next, in step S2, the control device 40 calculates the amount of carbon dioxide generated (amount generated per unit time (unit: mol / min); the same applies below). Specifically, the control device 40 multiplies the detection value of the CO2 sensor 63 (carbon dioxide concentration) by the detection value of the flow sensor 55 (air flow rate).

[0094] Furthermore, the control device 40 acquires the detection value of the first temperature sensor 64 in step S3, and corrects the amount of carbon dioxide generated in step S4. During the compost production process, the pressure of the air flowing through the exhaust pipe 61 is approximately constant, but the temperature of the air flowing through the exhaust pipe 61 changes in response to changes in the temperature of the raw material M, causing a change in the volume of the air.

[0095] Therefore, in step S4, the control device 40 multiplies the amount of carbon dioxide generated by a correction coefficient corresponding to the detection value (i.e., the air temperature) of the first temperature sensor 64. The correction coefficient is derived based on the gas state equation and is stored in advance in the control device 40. This allows the compost production apparatus 1 to accurately calculate the amount of carbon dioxide generated.

[0096] Next, the control device 40 calculates the total amount of carbon dioxide in step S5. The total amount of carbon dioxide is the total amount of carbon dioxide (unit: mol) from the start of compost production to the present time, and is calculated by integrating the amount of carbon dioxide generated.

[0097] Furthermore, in step S6, the control device 40 determines whether the total amount of carbon dioxide is equal to or greater than a predetermined total amount judgment value. The predetermined total amount judgment value corresponds to the total amount of carbon dioxide corresponding to raw material M having a protein content lower than the protein content that effectively functions as a fertilizer and a fiber content that effectively functions as a fertilizer. The predetermined total amount judgment value is derived from a preliminary test that is performed in advance before compost production. In the preliminary test, a portion of raw material M is used as a sample.

[0098] Fig. 10 is a diagram showing the relationship between the flow rate of carbon dioxide per unit time and the test time in the preliminary test, and Fig. 11 is a diagram showing the relationship between the total amount of carbon dioxide and the test time in the preliminary test.

[0099] As shown in Figure 10, the flow rate of carbon dioxide increases and then decreases as the decomposition of the sample progresses from the start of the test (time t10). Furthermore, by examining the composition of the sample in the preliminary test, it is possible to determine the timing (time t11) at which the protein content falls below the content at which the protein effectively functions as fertilizer.

[0100] Since ammonia is generated when protein is decomposed, the ammonia concentration may be measured in a preliminary test to determine the timing at which the protein content falls below the level at which the protein effectively functions as a fertilizer.

[0101] When the carbon dioxide flow rate is stable at a relatively low value (after time t12), the fiber content is lower than the content at which the fiber effectively functions as a fertilizer. Therefore, it is possible to clarify the range of carbon dioxide flow rates (between time t11 and time t12) corresponding to samples that have a protein content lower than the content at which the protein effectively functions as a fertilizer and a fiber content at which the fiber effectively functions as a fertilizer.

[0102] 11, after time t11 when the carbon dioxide flow rate stabilizes at a relatively low value, the increase in the total amount of carbon dioxide relative to the test time decreases and approaches saturation. This makes it possible to identify the range of the total amount of carbon dioxide (between time t11 and time t12) corresponding to samples that have a protein content lower than the content at which the protein effectively functions as a fertilizer and a fiber content at which the fiber effectively functions as a fertilizer, i.e., samples that can be used as fully matured compost.

[0103] Furthermore, it is possible to determine the range of the total amount of carbon dioxide corresponding to raw material M equivalent to fully matured compost, i.e., raw material M having a protein content lower than the content at which protein effectively functions as fertilizer and a fiber content at which fiber effectively functions as fertilizer, by using the ratio between the total amount of the sample and the total amount of raw material M contained in tank 10. The predetermined total amount judgment value is determined from the range of the total amount of carbon dioxide corresponding to fully matured compost and is stored in advance in control device 40.

[0104] 9, if the total amount of carbon dioxide is equal to or greater than the predetermined total amount judgment value, the raw material M has become fully matured compost. In this case (YES in step S6), the control device 40 determines that the compost (i.e., fully matured compost) is complete, and ends the production of the compost in step S7, terminating the program.

[0105] On the other hand, if the total amount of carbon dioxide is less than the predetermined total amount judgment value (NO in step S6), the raw material M is in the state of immature compost or semi-mature compost, and the control device 40 returns the program to step S1.

[0106] When the program ends, the control device 40 discharges the compost from the tank 10. Specifically, the control device 40 controls the lifting mechanism 32 to position the rotation mechanism 33 at rotation position Po2 and lift the tank 10. Next, the control device 40 controls the tilting mechanism 34 to tilt the tank 10. Furthermore, with the lid member removed from the opening 13a, the control device 40 controls the rotation mechanism 33 to rotate the tank 10. This causes the compost (i.e., fully matured compost) to be discharged from the opening 13a.

[0107] As described above, according to this embodiment, the compost production apparatus 1 includes a plurality of tanks 10 that store raw compost material M, a tank rotation device 30 having a rotation mechanism 33 that rotates one of the plurality of tanks 10, and a control device 40 that controls the tank rotation device 30. The tank rotation device 30 further includes a movement mechanism 31 that moves the rotation mechanism 33. The control device 40 controls the movement mechanism 31 to move the rotation mechanism 33 to a position corresponding to one of the tanks 10. In this way, the rotation mechanism 33 rotates one tank 10 out of the multiple tanks 10. Therefore, the number of parts in the rotation mechanism 33 can be reduced compared to when the rotation mechanism 33 drives multiple tanks 10 simultaneously. This reduces the cost of the compost production apparatus 1. Furthermore, compost can be produced using multiple tanks 10, and the multiple tanks 10 can be rotated at different times. This allows compost to be produced efficiently.

[0108] Each of the multiple tanks 10 has an opening 13a through which compost is discharged. The tank rotation device 30 further has a tilting mechanism 34 that tilts one of the tanks 10 so that the opening 13a faces downward. The control device 40 controls the tilting mechanism 34 to tilt one of the tanks 10, and controls the rotation mechanism 33 to rotate one of the tanks 10, thereby discharging the compost from the opening 13a. In this way, control device 40 tilts and rotates tank 10, causing compost to be discharged from opening 13a of tank 10. Therefore, compost can be efficiently discharged from opening 13a without having a discharge mechanism for discharging compost inside tank 10, and the cost of compost production apparatus 1 can be reduced.

[0109] The rotation mechanism 33 also includes a drive roller 33b1 and a driven roller 33b2 that come into contact with the outer peripheral surface of one tank 10 and rotate the one tank 10 about the central axis Lc of the one tank 10. When the tank rotation device 30 is viewed along the central axis Lc with the drive roller 33b1 and the driven roller 33b2 in contact with the one tank 10, a first angle θ1 formed between a first imaginary line L1 connecting a first contact point Pt1 between the drive roller 33b1 and the outer peripheral surface of the tank 10 and the central axis Lc and a vertical line Lv passing through the central axis Lc is smaller than a second angle θ2 formed between a second imaginary line L2 connecting a second contact point Pt2 between the driven roller 33b2 and the outer peripheral surface and the central axis Lc and the vertical line Lv. According to this, the weight of the tank 10 acting on the drive roller 33b1 is greater than the weight of the tank 10 acting on the driven roller 33b2. Therefore, in this case, the drive roller 33b1 can rotate the tank 10 more efficiently than when the weight of the tank 10 acting on the drive roller 33b1 and the weight of the tank 10 acting on the driven roller 33b2 are equal. Furthermore, when one tank 10 is rotated by the drive roller 33b1 and the driven roller 33b2, the number of parts of the tank rotation device 30 can be reduced compared to when the tank 10 is rotated by two drive rollers 33b1, and the cost of the compost production apparatus 1 can be reduced.

[0110] Furthermore, when the tank rotation device 30 is viewed along the central axis Lc with the drive roller 33b1 and driven roller 33b2 in contact with one tank 10, the first angle θ1 and the second angle θ2 are set to values ​​at which the center of gravity of the one tank 10 moves in the horizontal direction between the first contact point Pt1 and the second contact point Pt2. This causes the center of gravity of the tank 10 to move in the horizontal direction between the first contact point Pt1 and the second contact point Pt2 that support the tank 10. This makes it possible to stabilize the rotation of the tank 10.

[0111] Furthermore, the rotation mechanism 33 rotates one tank 10 by the frictional force generated between the outer circumferential surface of the tank 10 and the drive roller 33b1. According to this, when the weight of the tank 10 acting on the drive roller 33b1 is greater than the weight of the tank 10 acting on the driven roller 33b2, the frictional force is greater than when the weight of the tank 10 acting on the drive roller 33b1 and the weight of the tank 10 acting on the driven roller 33b2 are equal, thereby stabilizing the rotation of the tank 10.

[0112] The compost production apparatus 1 also includes an air supply device 50 that supplies air to one of the tanks 10, and a carbon dioxide concentration sensor 63 that detects the concentration of carbon dioxide discharged from one of the tanks 10. The raw material M contains organic matter. Based on the detection value of the carbon dioxide concentration sensor 63, the control device 40 calculates the total amount of carbon dioxide produced by the decomposition of the organic matter by the microorganisms, and determines that the compost is complete if the total amount of carbon dioxide is equal to or greater than a predetermined total amount judgment value. Conventionally, the determination of whether or not the compost is complete has been made, for example, by the feel of the composted raw material M, and is based on the manufacturer's experience. In contrast, in the present disclosure, the determination of whether or not the compost is complete is made based on the total amount of carbon dioxide produced by the decomposition of organic matter by microorganisms. Therefore, it is possible to appropriately determine whether or not the compost is complete.

[0113] The organic matter also includes fiber that can be used as fertilizer, and protein that can be used as fertilizer and is decomposed by microorganisms more quickly than fiber. The predetermined total amount judgment value corresponds to the total amount of carbon dioxide corresponding to raw material M having a protein content lower than the protein content that effectively functions as fertilizer and a fiber content that effectively functions as fertilizer. This allows for the appropriate production of fully matured compost, which is compost containing fibrous material that can be used as fertilizer.

[0114] Next, the compost production apparatus 1 according to the first modification of this embodiment will be described, focusing mainly on the differences from the above embodiment.

[0115] 12 is a schematic diagram showing the configuration of an exhaust device 60 according to a first modified example of this embodiment. In the first modified example, the exhaust device 60 further includes an ammonia detector 164 that detects the concentration of ammonia contained in the air flowing through the exhaust pipe 61. The ammonia detector 164 is disposed in the exhaust pipe 61 between the tank 10 and the dryer 62.

[0116] The ammonia detection device 164 includes a container 164a in which water W is stored, and an ammonia concentration sensor 164b that detects the concentration of ammonia. The ammonia concentration sensor 164b is, for example, a constant-potential electrolysis type ammonia concentration sensor. The air flowing through the exhaust pipe 61 is discharged into the water W in the container 164a. The ammonia concentration sensor 164b detects the concentration of ammonia dissolved in the water W in the container 164a. The detection value of the ammonia concentration sensor 164b is sent to the control device 40.

[0117] As the decomposition of the protein progresses, the concentration of ammonia dissolved in the water W in the container 164a, that is, the detection value of the ammonia concentration sensor 164b, increases.

[0118] Furthermore, in this case, the control device 40 executes the flowchart shown in Fig. 13. Fig. 13 is a flowchart executed by the control device 40 of the compost production apparatus 1 according to the first modified embodiment of the present disclosure. The flowchart in Fig. 13 adds step S18 to the flowchart in Fig. 10.

[0119] In step S18, the control device 40 determines whether the integrated value of the ammonia concentration is equal to or greater than a predetermined integrated judgment value. In this first modified example, the control device 40 calculates the integrated value of the ammonia concentration by integrating the detection values ​​of the ammonia concentration sensor 164b from the start of compost production to the present time. As protein decomposition progresses, the protein content decreases and the integrated value of the ammonia concentration increases. The predetermined integrated judgment value corresponds to the integrated value of the ammonia concentration corresponding to a protein content lower than the content at which the protein effectively functions as a fertilizer. The predetermined integrated judgment value is derived in advance by measuring the integrated value of the ammonia concentration in a preliminary test and is pre-stored in the control device 40.

[0120] If the protein decomposition is relatively low, the protein content is equal to or higher than the protein content at which the protein effectively functions as fertilizer, and the integrated value of the ammonia concentration is lower than the predetermined integrated judgment value (NO in step S18), the control device 40 returns the program to step S1. On the other hand, if the protein decomposition has progressed, the protein content is lower than the protein content at which the protein effectively functions as fertilizer, and the integrated value of the ammonia concentration is equal to or higher than the predetermined integrated judgment value (YES in step S18), the control device 40 advances the program to step S7.

[0121] This allows the compost production apparatus 1 to accurately determine whether the protein content has fallen below the content at which the protein effectively functions as a fertilizer, and ensures that fully matured compost is produced.

[0122] The ammonia detector 164 may detect the ammonia concentration of the air discharged from a branch pipe (not shown) branching off from the exhaust pipe 61 between the tank 10 and the dryer 62. In this case, the ammonia detector 164 is disposed with the tip of the branch pipe positioned in the water W in the container 164a. The exhaust device 60 may further include a heater (not shown) for heating at least one of the exhaust pipe 61 and the branch pipe. In this case, it is possible to prevent condensation from forming inside the exhaust pipe 61 and the branch pipe, and to prevent ammonia from dissolving in the condensation. Therefore, the ammonia detector 164 can accurately detect the concentration of ammonia contained in the air flowing through the exhaust pipe 61.

[0123] The ammonia concentration sensor 164b may be disposed inside the exhaust pipe 61 to detect the concentration of ammonia in the air flowing through the exhaust pipe 61. In this case, the ammonia concentration sensor 164b may be an infrared absorption type ammonia concentration sensor. Furthermore, in this case, the ammonia detection device 164 does not include the container 164a.

[0124] Next, a compost production apparatus 1 according to a second modification of this embodiment will be described, focusing mainly on the differences from the above embodiment.

[0125] In the second variant, the predetermined total amount judgment value corresponds to the total amount of carbon dioxide corresponding to raw material M (i.e., semi-mature compost) having a protein content and fiber content that function effectively as fertilizer, and in which the content of decomposition products (sugars and starch) that can be used as fertilizer when the content is below a predetermined content, is below a predetermined content.

[0126] In this case, the flow rate and total amount of carbon dioxide corresponding to the sample at the time when the sugar and starch contents are below a predetermined level in the preliminary test are derived, and the flow rate and total amount of carbon dioxide corresponding to the sample whose sugar and starch contents are below the predetermined level and whose protein and fiber contents are sufficient to function effectively as a fertilizer, i.e., the sample usable as semi-mature compost, are determined.

[0127] Furthermore, by using the ratio between the total amount of the sample and the total amount of raw material M contained in the tank 10, it is possible to determine the range of the total amount of carbon dioxide corresponding to raw material M corresponding to semi-mature compost, i.e., raw material M having sugar and starch contents below a predetermined content and protein and fiber contents that function effectively as fertilizer. The predetermined total amount judgment value is determined from the range of the total amount of carbon dioxide corresponding to semi-mature compost.

[0128] In this case, when the total amount of carbon dioxide reaches or exceeds the predetermined total amount judgment value in step S6 of Figure 9, the control device 40 determines that the compost (i.e., semi-mature compost) is complete. In other words, in this case, the compost production apparatus 1 can properly produce semi-mature compost.

[0129] In this case, the flowchart of Figure 13 may be executed, and the predetermined integrated judgment value may be set to the ammonia concentration when the sugar and starch contents are below a predetermined content and the protein content is such that it effectively functions as a fertilizer. In this case, the compost production apparatus 1 can reliably produce semi-mature compost.

[0130] According to this second modification, the organic matter includes fiber usable as fertilizer, protein usable as fertilizer and decomposed by microorganisms at a faster rate than fiber, and decomposition products (sugars and starch) that can be used as fertilizer when their content is below a predetermined content and that are decomposed by microorganisms at a faster rate than protein. The predetermined total amount judgment value corresponds to the total amount of carbon dioxide corresponding to raw material M having a protein content and fiber content that are below a predetermined content and that allow the protein and fiber to function effectively as fertilizer. This allows for the appropriate production of so-called semi-mature compost, which is compost containing protein and fiber that can be used as fertilizer.

[0131] Next, a compost production apparatus 1 according to a third modification of this embodiment will be described, focusing mainly on the differences from the above embodiment.

[0132] In this third modified example, the control device 40 adjusts the amount of air supplied by controlling the air supply device 50 based on the detection value of the CO2 sensor 63. The control device 40 adjusts the amount of air supplied so that the concentration of carbon dioxide flowing through the exhaust pipe 61 reaches a predetermined target value (hereinafter referred to as the CO2 target value).

[0133] The CO2 target value is the carbon dioxide concentration corresponding to when oxygen deficiency in the microorganisms is suppressed and when a decrease in the temperature of the raw material M due to the supply of air is suppressed, and corresponds to the carbon dioxide concentration when the decomposition of the raw material M is stably carried out. In other words, in this third modified example, the amount of air supplied is adjusted according to the state of decomposition of the raw material M. This allows for the efficient decomposition of the raw material M.

[0134] Specifically, the control device 40 calculates the amount of carbon dioxide generated (unit: mol / min) by multiplying the detection value (unit: mol / m) of the CO2 sensor 63 by the detection value (unit: m3 / min) of the flow rate sensor 55. Next, the control device 40 determines the value obtained by dividing the amount of carbon dioxide generated by the CO2 target value (unit: mol / m3) as the target value for the amount of air supplied (hereinafter referred to as the target air supply amount value).

[0135] Furthermore, the control device 40 adjusts the amount of air supply by feedback control, which adjusts at least one of the driving amount of the air blower 51 and the operating amount of the throttle valve of the flow control valve 54, based on the deviation between the detection value of the flow sensor 55 and the target air supply amount.

[0136] For example, when the target air supply amount and the detection value of flow sensor 55 are both at the first flow rate and the detection value of CO2 sensor 63 is at the target CO2 value, if the tank 10 is rotated as shown by the dashed-dotted line in Fig. 8, and the actual amount of carbon dioxide generated increases, the detection value of CO2 sensor 63 becomes higher than the target CO2 value. In response to this, the amount of carbon dioxide generated calculated by control device 40 increases, and when an air supply amount target value greater than the first flow rate is calculated, the amount of air supplied per unit time by air supply device 50 increases. As a result, the detection value of flow sensor 55 approaches the target air supply amount that is greater than the first flow rate, and the detection value of CO2 sensor 63 decreases and approaches the target CO2 value.

[0137] Furthermore, as the decomposition of raw material M progresses and the actual amount of carbon dioxide generated decreases, the detection value of CO2 sensor 63 falls below the CO2 target value. In response to this, the amount of carbon dioxide generated calculated by control device 40 decreases, and when an air supply volume target value smaller than the first flow rate is calculated, the amount of air supplied per unit time by air supply device 50 decreases. As a result, the detection value of flow sensor 55 approaches the air supply volume target value smaller than the first flow rate, and the detection value of CO2 sensor 63 increases and approaches the CO2 target value. In this way, control device 40 controls air supply device 50 to adjust the amount of air supplied so that the detection value of CO2 sensor 63 approaches the CO2 target value. At this time, the concentration of carbon dioxide discharged from tank 10 is approximately 0.1 to 0.2 kg / m 3 (mass percent concentration).

[0138] According to the third modified example, the control device 40 controls the air supply device 50 based on the detected value of the carbon dioxide concentration sensor 63 to adjust the amount of air supplied. The control device 40 controls the amount of air supplied based on the detected value of the carbon dioxide concentration sensor 63, for example, to bring the detected value of the carbon dioxide concentration sensor 63 closer to the target CO2 value. This makes it possible to stabilize and therefore improve the efficiency of the decomposition of the raw material M by the microorganisms.

[0139] In the third modified example, the raw material M is efficiently decomposed as described above, and therefore the decomposition of the raw material M proceeds more quickly than in the above embodiment. Therefore, as shown by the dashed dotted line in Figure 8, the flow rate of carbon dioxide is higher in the third modified example from the beginning to the middle of the production process than in the above embodiment, and the production of compost is completed earlier (time t14).

[0140] Next, a compost production apparatus 1 according to a fourth modification of this embodiment will be described, focusing mainly on the differences from the above embodiment.

[0141] Fig. 14 is a front view of the tank 10 and the tank rotation device 30 according to a fourth modified example of the embodiment of the present disclosure. Note that the support 20 is omitted in Fig. 14. In this fourth modified example, the number of tanks 10 is one.

[0142] The tank rotation device 30 of this fourth modified example does not have a movement mechanism 31, but has a support base 235. The support base 235 is arranged so that it cannot move relative to the installation surface of the compost production apparatus 1 (i.e., it is fixed to the installation surface). In other words, the tank rotation device 30 of this fourth modified example does not move the rotation mechanism 33. In addition, a lifting mechanism 32 and a tilting mechanism 34 are arranged on the support base 235.

[0143] In the fourth modified example, as in the above embodiment, the rotation mechanism 33 rotates one tank 10. When the tank rotation device 30 is viewed along the central axis Lc with the rotation mechanism 33 located at the rotation position Po2, a first angle θ1 formed between a first imaginary line L1 connecting a first contact point Pt1 between the drive roller 33b1 and the outer peripheral surface of the tank 10 and the central axis Lc and a vertical line Lv passing through the central axis Lc is smaller than a second angle θ2 formed between a second imaginary line L2 connecting a second contact point Pt2 between the driven roller 33b2 and the outer peripheral surface and the central axis Lc and the vertical line Lv.

[0144] According to the fourth modified example, the compost production apparatus 1 includes a tank 10 that contains raw compost material M, a tank rotation device 30 having a rotation mechanism 33 that rotates the tank 10, and a control device 40 that controls the tank rotation device 30. The rotation mechanism 33 includes a drive roller 33b1 and a driven roller 33b2 that come into contact with the outer circumferential surface of the tank 10 and rotate the tank 10 about the central axis Lc of the tank 10. When the tank rotation device 30 is viewed along the central axis Lc with the drive roller 33b1 and driven roller 33b2 in contact with one tank 10, the first angle θ1 formed by the first virtual line L1 connecting the first contact point Pt1 between the drive roller 33b1 and the outer peripheral surface of the tank 10 to the central axis Lc and the vertical line Lv passing through the central axis Lc is smaller than the second angle θ2 formed by the second virtual line L2 connecting the second contact point Pt2 between the driven roller 33b2 and the outer peripheral surface to the central axis Lc and the vertical line Lv.

[0145] Therefore, in the fourth modified example as well, the weight of the tank 10 acting on the drive roller 33b1 is greater than the weight of the tank 10 acting on the driven roller 33b2. Therefore, in this case, the drive roller 33b1 can rotate the tank 10 more efficiently than when the weight of the tank 10 acting on the drive roller 33b1 is equal to the weight of the tank 10 acting on the driven roller 33b2. Furthermore, when the tank 10 is rotated by the drive roller 33b1 and the driven roller 33b2, the number of parts of the tank rotation device 30 can be reduced compared to when the tank 10 is rotated by two drive rollers 33b1, and the cost of the compost production apparatus 1 can be reduced.

[0146] In this fourth modified example, the tank rotation device 30 may not have at least one of the lifting mechanism 32 and the tilting mechanism 34. If the tank rotation device 30 does not have the lifting mechanism 32, the compost production apparatus 1 may not have the support 20. If the tank rotation device 30 does not have both the lifting mechanism 32 and the tilting mechanism 34, the support platform 235 supports the second base 33a of the rotation mechanism 33. In this case, the support platform 235 and the second base 33a may be integrated. In this fourth modified example, the compost production apparatus 1 may have multiple tanks 10. In this case, the compost production apparatus 1 may have multiple tank rotation devices 30, and the tank rotation devices 30 are arranged to correspond to the tanks 10.

[0147] Next, a compost production apparatus 1 according to another modification of this embodiment will be described, focusing mainly on the differences from the above embodiment.

[0148] For example, the control device 40 may calculate a degree of maturity indicating the degree of decomposition of the raw material M and display it on the display unit. Specifically, the degree of maturity is the ratio of the total amount of carbon dioxide calculated in step S5 shown in FIG. 10 to the total amount of carbon dioxide corresponding to the predetermined total amount judgment value. This allows the operator to grasp the degree of decomposition of the raw material M. Furthermore, the detection values ​​of the CO2 sensor 63, the flow sensor 55, the first temperature sensor 64, and the second temperature sensor 70 may be displayed on the display unit. In this case, the display unit allows the operator to quickly detect abnormalities in the production of compost. An abnormality in the production of compost may be, for example, the temperature of the raw material M being relatively low and the raw material M not being properly decomposed.

[0149] Furthermore, in the compost production process, the control device 40 may rotate the tank 10 based on the detection value (carbon dioxide concentration) of the CO2 sensor 63. In this case, the control device 40 rotates the tank 10 when the detection value of the CO2 sensor 63 falls below a predetermined predetermined concentration judgment value. The predetermined concentration judgment value corresponds to the carbon dioxide concentration when the decomposition of the raw material M has progressed sufficiently. The predetermined concentration judgment value is derived through the above-mentioned preliminary test or the like and is stored in advance in the control device 40.

[0150] The concentration of carbon dioxide gradually decreases as the decomposition of raw material M progresses. Therefore, when the detection value of CO2 sensor 63 becomes equal to or less than the predetermined concentration judgment value, the decomposition of raw material M has progressed sufficiently. Therefore, the control device 40 can rotate the tank 10 efficiently by rotating the tank 10 when the detection value of CO2 sensor 63 becomes equal to or less than the predetermined concentration judgment value.

[0151] Alternatively, the first angle θ1 and the second angle θ2 may be equal. Furthermore, the pair of rollers 33b may include two drive rollers 33b1 without including a driven roller 33b2. The outer circumferential surfaces of the pair of rollers 33b may be uneven, or the outer circumferential portions of the pair of rollers 33b may be made of a material with relatively high frictional resistance (e.g., urethane resin). This increases the frictional resistance between the outer circumferential surfaces of the pair of rollers 33b and the outer circumferential surface of the tank 10, thereby stabilizing the rotation of the tank 10. The outer circumferential surfaces of the pair of rollers 33b may also have teeth. In this case, the first groove portion 11 and the second groove portion 12 have teeth that fit with the teeth of the pair of rollers 33b.

[0152] The rotation mechanism 33 may further include a mechanism for suppressing movement of the tank 10 in the Y direction relative to the rotation mechanism 33. For example, the mechanism may be such that annular recesses are formed in the peripheries of the first side wall 13 and the second side wall 14 of the tank 10, and the rotation mechanism 33 may further include rollers that fit into the recesses. Note that the support 20 may also include such a mechanism.

[0153] Furthermore, the air supply device 50 may not be provided with the flow rate sensor 55, and the air flow rate may be estimated from the drive amount of the air blower 51 and the operation amount of the throttle valve.

[0154] FIG. 15 is a schematic diagram showing the configurations of a tank 10, an air supply device 50, and an exhaust device 60 according to another modification of the embodiment of the present disclosure. In this modification, the air supply pipe 52 and the exhaust pipe 61 are connected to a rotary joint 310c located in the center of the second side wall 14 of the tank 10. The rotary joint 310c is a so-called rotary joint, and connects the air supply pipe 52 and the exhaust pipe 61 to the tank 10 so that they can rotate relative to the tank 10. This allows the air blowout pipe 53 to be located at the bottom of the tank 10, and the first end of the exhaust pipe 61 to be located at the top of the tank 10, even when the tank 10 is rotating. The air supply device 50 may also have multiple air blowout pipes 53 connected to the rotary joint 310c.

[0155] Furthermore, the opening 13a of the tank 10 may be located on the outer peripheral surface. Furthermore, the first joint 10a and the second joint 10b may be located on the outer peripheral surface of the tank 10. A mesh-like bottom plate (not shown) on which the raw material M is placed may be located inside the tank 10. In this case, an air blow-out pipe 53 may be located below the bottom plate. Furthermore, the shape of the tank 10 may be spherical or prismatic.

[0156] Alternatively, the multiple tanks 10 may be arranged in a matrix along the X and Y directions. In this case, there may be multiple tank rotation devices 30, and the movement mechanism 31 may be configured to allow the rotation mechanism 33 to move along the X and Y directions. Specifically, a pair of rails R may be arranged along the X and Y directions, or the compost production apparatus 1 may not be equipped with a pair of rails R, and the tank rotation device 30 may self-propel, causing the movement mechanism 31 to move the rotation mechanism 33 to a position corresponding to one tank 10.

[0157] Furthermore, an operator may operate the input unit of the control device 40 to individually control the rotation of the tank 10, the movement mechanism unit 31, and the like. [Explanation of symbols]

[0158] 1 Compost production equipment 10 Tank 13a opening 30 Tank Rotation Device 31 Moving mechanism section 32 Lifting mechanism 33 Rotation mechanism 33b1 Drive roller 33b2 Driven roller 34 Tilt mechanism section 40 Control device 50 Air supply device 60 Exhaust system 63 Carbon dioxide concentration sensor L1 First virtual line L2 Second virtual line Lc central axis (rotation axis) Lv plumb line M Raw material Pt1 1st contact point Pt2 2nd contact point θ1 1st angle θ2 2nd angle

Claims

1. a plurality of tanks for containing raw materials for compost; a tank rotation device having a rotation mechanism that rotates one of the plurality of tanks; a control device for controlling the tank rotation device, the tank rotation device further includes a movement mechanism that moves the rotation mechanism, the control device controls the movement mechanism to move the rotation mechanism to a position corresponding to one of the tanks; Compost production equipment.

2. Each of the plurality of tanks has an opening for discharging the compost, the tank rotation device further includes a tilting mechanism that tilts the one tank in a direction in which the opening faces downward, the control device controls the tilting mechanism to tilt the one tank and controls the rotation mechanism to rotate the one tank, thereby discharging the compost from the opening. The composting apparatus according to claim 1.

3. the rotation mechanism includes a drive roller and a driven roller that come into contact with an outer circumferential surface of the one tank and rotate the one tank around a rotation axis of the one tank, When the tank rotation device is viewed along the rotation axis in a state in which the drive roller and the driven roller are in contact with one tank, a first angle formed by a first imaginary line connecting a first contact point between the drive roller and the outer peripheral surface and the rotation axis and a vertical line passing through the rotation axis is smaller than a second angle formed by a second imaginary line connecting a second contact point between the driven roller and the outer peripheral surface and the rotation axis and the vertical line. The composting apparatus according to claim 1.

4. when the tank rotation device is viewed along the rotation axis with the drive roller and the driven roller in contact with the one tank, the first angle and the second angle are determined to be values ​​by which the center of gravity of the one tank moves in the horizontal direction between the first contact point and the second contact point. The composting apparatus according to claim 3.

5. the rotation mechanism rotates the one tank by frictional force generated between the outer circumferential surface and the drive roller; The composting apparatus according to claim 3.

6. an air supply device that supplies air to the one tank; a carbon dioxide concentration sensor that detects the concentration of carbon dioxide discharged from the one tank; The raw material includes an organic substance, The control device calculating a total amount of carbon dioxide produced by the decomposition of the organic matter by microorganisms based on the detected value of the carbon dioxide concentration sensor; If the total amount is equal to or greater than a predetermined total amount judgment value, the compost is judged to be complete. The composting apparatus according to claim 1.

7. The organic matter contains fiber that can be used as a fertilizer, and protein that can be used as a fertilizer and is decomposed by microorganisms at a faster rate than the fiber, the predetermined total amount judgment value corresponds to the total amount corresponding to the raw material having a protein content lower than the content at which the protein effectively functions as a fertilizer and a fiber content at which the fiber effectively functions as a fertilizer; 7. The composting apparatus according to claim 6.

8. The organic matter includes a fiber that can be used as a fertilizer, a protein that can be used as a fertilizer and that is decomposed by microorganisms at a faster rate than the fiber, and a decomposition product that can be used as a fertilizer when its content is equal to or less than a predetermined content and that is decomposed by microorganisms at a faster rate than the protein, The predetermined total amount judgment value corresponds to the total amount corresponding to the raw material having a protein content and a fiber content such that the content of the decomposition product is equal to or less than the predetermined content and the protein and the fiber function effectively as a fertilizer.

7. The composting apparatus according to claim 6.

9. the control device controls the air supply device based on the detected value of the carbon dioxide concentration sensor to adjust the amount of air supplied.

7. The composting apparatus according to claim 6.

10. a tank for storing raw materials for compost; a tank rotation device having a rotation mechanism that rotates the tank; a control device for controlling the tank rotation device, the rotation mechanism includes a drive roller and a driven roller that come into contact with an outer circumferential surface of the tank and rotate the tank around a rotation axis of the tank; When the tank rotation device is viewed along the rotation axis with the drive roller and the driven roller in contact with the tank, a first angle formed by a first imaginary line connecting a first contact point between the drive roller and the outer peripheral surface and the rotation axis and a vertical line passing through the rotation axis is smaller than a second angle formed by a second imaginary line connecting a second contact point between the driven roller and the outer peripheral surface and the rotation axis and the vertical line. Compost production equipment.

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