Manufacturing method for granular material

Abstract

This invention relates to a technology for efficiently and simply producing recycled materials from combustible waste with a high moisture content. [Solution] A method for producing granular material according to one embodiment of the present invention is a method for producing granular material using combustible waste having a moisture content of 80% by mass or more, comprising: a combustible waste containment step of containing combustible waste having a moisture content of 80% by mass or more in a containment section which is the internal space of a treatment tank; and a heating and stirring step of generating granular material by heating and stirring a material to be treated, which includes a granular stirring medium generated by heating waste containing used absorbent articles, and the combustible waste, to a temperature of 180°C to 400°C or lower.

Description

Technical Field

[0001] The present invention relates to a recycling technology for combustible waste with a high water content. relates to.

Background Art

[0002] From the perspective of reducing greenhouse gas emissions, it is desired to recycle waste without incineration. Therefore, a technology for pyrolyzing waste to produce carbide and producing recycled materials is known. For example, in Patent Document 1, a plastic-based waste and an organic waste are each crushed, a processed material obtained by mixing, compressing, and heating them is produced, and the processed material is continuously introduced from the charging section of a furnace body preheated to 300°C or higher and carbonized, and a carbonization method for waste is described.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Combustible waste with a high water content such as food waste requires preliminary treatment such as dehydration and drying before carbonization treatment and addition of a combustion aid in the carbonization treatment in order to prevent a decrease in heating efficiency. Therefore, a technology for efficiently and simply producing recycled materials from combustible waste with a high water content is required.

[0005] The present invention relates to a technology for efficiently and simply producing recycled materials from combustible waste with a high water content.

Means for Solving the Problems

[0006] A method for producing granular material according to one embodiment of the present invention is a method for producing granular material using combustible waste having a water content of 80% by mass or more, The combustible waste containment step involves containing combustible waste having a water content of 80% by mass or more in the containment section, which is the internal space of the treatment tank. The process includes a heating and stirring step in which a granular stirring medium, generated by heating waste including used absorbent articles within the containment section, and the combustible waste to be treated, are stirred while being heated to a temperature of 180°C to 400°C to generate granular material. [Effects of the Invention]

[0007] According to the present invention, it is possible to efficiently and simply produce recycled materials from combustible waste with a high moisture content. [Brief explanation of the drawing]

[0008] [Figure 1] This is a schematic diagram showing a processing apparatus according to the first embodiment of the present invention. [Figure 2] This is a schematic cross-sectional view of the processing tank of the above-mentioned apparatus, and is a diagram showing the cross-section of the processing tank as viewed from the front. [Figure 3] This is a schematic cross-sectional view of the processing tank of the above-mentioned apparatus, and is a diagram showing a cross-section of the processing tank viewed from the side. [Figure 4] This flowchart shows a method for producing granular material using the above-described processing apparatus. [Figure 5] This figure schematically illustrates the effects of the stirring medium containing the superabsorbent polymer used in the above manufacturing method, where (A) shows the state before water absorption by the superabsorbent polymer and (B) shows the state after water absorption by the superabsorbent polymer. [Figure 6] This is a schematic diagram showing a modified apparatus according to the above embodiment. [Figure 7] This is a schematic cross-sectional view of the processing tank of the above-mentioned apparatus, and is a diagram showing the cross-section of the processing tank as viewed from the front. [Figure 8] This is a flowchart showing a method for producing granular material according to a second embodiment of the present invention. [Figure 9]This is a schematic diagram illustrating a method for producing granular material according to the third embodiment of the present invention. [Modes for carrying out the invention]

[0009] <Brief description of embodiments of the present invention> A method for producing granular material according to one embodiment of the present invention is characterized by placing a granular stirring medium derived from used absorbent articles in a treatment tank, placing combustible waste having a moisture content of 80% by mass or more in the treatment tank, and heating and stirring these materials to be treated. By mixing and heating the combustible waste with a high moisture content and the stirring medium, the combustible waste can be heated uniformly and efficiently, and granular material that can be recycled can be produced. As a result, pretreatment such as dewatering and drying, and combustion aids are unnecessary for the combustible waste, and recycled material can be produced from combustible waste efficiently and simply. Therefore, the method for producing granular material according to this embodiment contributes to promoting waste recycling and, in turn, to the realization of a resource-recycling society.

[0010] In one embodiment of the present invention, "granular" refers to the shape of each fragment of the crushed material to be processed. Furthermore, "granular body" refers to an aggregate of multiple fragments that are separated from each other. By forming the product derived from combustible waste into a granular body, it can be made into a form that is easy to handle as a recycled material. The particle size of the granular body is preferably 10 μm or more, more preferably 30 μm or more, preferably 5 cm or less, more preferably 1 cm or less, and even more preferably 0.5 cm or less. The particle size of the granular body refers to the maximum diameter of each fragment constituting the granular body. The detailed composition of the granular body will be described later.

[0011] In one embodiment of the present invention, combustible waste refers to waste mainly containing organic matter classified as combustible waste, and examples include food waste, paper, cloth, resin products, plants, wood products, rubber products, leather products, and mixtures thereof.

[0012] The combustible waste used in one embodiment of the present invention has a moisture content of 80% by mass or more. The moisture content of the combustible waste refers to the ratio of the mass of water in the combustible waste before heating to the total mass of the combustible waste before heating. The mass of water in the combustible waste before heating can be calculated, for example, as the ratio of the difference between the total mass of the combustible waste before heating and the mass of the combustible waste in a completely dried state (absolutely dry state). Examples of combustible waste with a high moisture content include food waste, sludge (organic sludge, inorganic sludge), and mixtures of these with other combustible waste. In one embodiment of the present invention, the above-mentioned combustible waste is preferably food waste that can be widely generated from households and businesses, and includes processing residues generated during the manufacturing and processing of food, processing scraps and unsold food generated during the distribution stage of food, and cooking scraps and leftovers generated during the consumption stage of food. In one embodiment of the present invention, kitchen waste with a high moisture content generated during the cooking process is used as the combustible waste.

[0013] In one embodiment of the present invention, an absorbent article means an article that absorbs excrement. The absorbent article includes, for example, at least one selected from sanitary products (sanitary napkins, tampons, etc.), disposable diapers, incontinence pads, urine pads, and panty liners. Incontinence pads refer to absorbent pads for mild to moderate incontinence that are attached to regular underwear, and urine pads refer to absorbent pads for moderate to severe incontinence that are mainly attached to disposable diapers.

[0014] Absorbent articles may contain superabsorbent polymers from the perspective of enhancing absorbency. A superabsorbent polymer is a resin that has the property of absorbing and holding moisture by having a crosslinked structure, and includes, for example, one or more superabsorbent polymers selected from polyacrylic acid, polyacrylate, partial crosslinked polymers of high molecular weight compounds having carboxyl groups or salts thereof, partial crosslinked polysaccharides, and the like. The partial crosslinked polymers of high molecular weight compounds having carboxyl groups or salts thereof include polyacrylate crosslinked polymers, poly(vinyl alcohol / acrylic acid salt) copolymers (crosslinked polymers), starch-acrylic acid salt graft copolymers (crosslinked polymers), polyvinyl alcohol-poly(maleic anhydride) graft copolymers (crosslinked polymers), and the like. The partial crosslinked polysaccharides include carboxymethyl cellulose salt crosslinked polymers and the like.

[0015] In addition, examples of the "salt" constituting the superabsorbent polymer include one or more salts selected from alkali metal salts (such as sodium salts, potassium salts, lithium salts, etc.), alkaline earth metal salts (such as calcium salts, magnesium salts, barium salts, etc.), ammonium salts (such as quaternary ammonium salts, quaternary alkylammonium salts, etc.).

[0016] In one embodiment of the present invention, the superabsorbent polymer preferably includes one or more superabsorbent polymers selected from polyacrylic acid, sodium polyacrylate, or crosslinked sodium polyacrylate.

[0017] Hereinafter, specific embodiments of the present invention will be described with reference to the drawings.

[0018] <First Embodiment> [Configuration of the Processing Apparatus] First, referring to FIGS. 1 to 3, a processing apparatus 100 that can be used for the method of manufacturing granules according to the first embodiment of the present invention will be described. The processing apparatus 100 includes a processing tank 101, a first heating unit 110, a second heating unit 120, an exhaust processing unit 130, and a control unit 140. The processing apparatus 100 is configured as, for example, a batch-type carbonization apparatus.

[0019] The processing tank 101 has a wall portion 101a and a storage portion 101b. The storage portion 101b is capable of accommodating the material to be processed by the processing device 100 and is configured as the internal space of the processing tank 101 surrounded by the wall portion 101a. Figures 1 to 3 show the interior of the storage portion 101b by displaying a vertical cross-section obtained by vertically cutting the wall portion 101a. In the processing tank 101, a part of the wall portion 101a is configured to be openable and closable as an input and / or output port for the material to be processed.

[0020] The processing tank 101 further includes one or more stirring shafts 102. Each stirring shaft 102 has a shaft portion 102a and a plurality of blade portions 102b. The shaft portion 102a is configured as a rod-shaped member that can rotate around a rotation axis C extending horizontally to the side. Both ends of the shaft portion 102a are supported by the wall portion 101a on the side of the housing portion 101b, and the portion between the ends supported by the wall portion 101a is located inside the housing portion 101b. The plurality of blade portions 102b are provided at intervals along the longitudinal direction. Each blade portion 102b also protrudes from the outer circumferential surface of the shaft portion 102a in various radial directions.

[0021] From the viewpoint of improving stirring efficiency, the processing tank 101 preferably has a plurality of stirring shafts 102. These stirring shafts 102 are preferably arranged such that their shaft portions 102a are substantially parallel to each other, for example, along a horizontal direction perpendicular to the vertical direction. In the example shown in Figure 3, the processing tank 101 has two stirring shafts 102.

[0022] The first heating unit 110 heats the wall portion 101a of the processing tank 101. In other words, the first heating unit 110 has the function of heating the containment portion 101b from the outside. In this embodiment, the first heating unit 110 has a heater 111 that heats the wall portion 101a. The heating method of the heater 111 is not limited, but from the viewpoint of facilitating temperature control, an electric heater is preferred. The various configurations of the heater 111, such as the installation position, can be determined in various ways depending on the configuration of the processing tank 101 and the properties of the material to be processed. For example, in Figure 2, the heater 111 is located at the bottom of the wall portion 101a, but it may also be located to the side or above the wall portion 101a.

[0023] The second heating unit 120 supplies heated gas to the containment section 101b. In other words, the second heating unit 120 has the function of directly heating the inside of the containment section 101b with hot air. In this embodiment, the second heating unit 120 has an air supply section 121, an exhaust section 122, a blower section 123, and a heating section 124. In this embodiment, the second heating unit 120 is a hot air circulating heating unit that heats the gas exhausted from the containment section 101b and supplies it to the containment section 101b by operating the blower section 123. By supplying the circulated gas to the containment section 101b, waste heat can be recovered and energy efficiency can be improved. The gas used in the second heating unit 120 is not particularly limited and may be air or an inert gas such as nitrogen.

[0024] The air supply unit 121 supplies gas to the containment unit 101b. In this embodiment, the air supply unit 121 is configured as a gas passage connecting the containment unit 101b and the blower unit 123 (heating unit 124). The air supply unit 121 is composed of one or more tubular members, including, for example, a tubular member provided to penetrate the wall portion 101a of the processing tank 101.

[0025] The exhaust section 122 exhausts gas from the containment section 101b. In this embodiment, the exhaust section 122 is configured as a gas passage connecting the blower section 123 and the containment section 101b. The exhaust section 122 is composed of one or more tubular members, including, for example, a tubular member provided to penetrate the wall section 101a of the processing tank 101. From the viewpoint of efficiently circulating the gas, it is preferable that the exhaust section 122 is positioned in the wall section 101a so as to face the supply air section 121 with the containment section 101b in between.

[0026] The air blower 123 blows gas to the air supply 121. The air blower 123 is composed of a blower such as a fan, blower, or compressor. The air blower 123 is positioned between the air supply 121 and the exhaust 122.

[0027] The heating unit 124 heats the gas supplied to the containment unit 101b. The heating unit 124 may be located on the exhaust side of the air blower unit 123, as shown in Figure 1, or on the supply side. Also, the heating unit 124 may be connected to the air blower unit 123, as shown in Figure 1, or it may be located at a distance from it. The heating unit 124 consists of a heater that heats the gas, and from the viewpoint of facilitating temperature control, it is preferable that it consists of an electric heater. The heating method and installation position of the heater constituting the heating unit 124 can be determined in various ways depending on the configuration of the processing tank 101 and the properties of the material to be processed.

[0028] Furthermore, in this embodiment, the second heating unit 120 has a flow rate adjustment unit 125 that adjusts the flow rate of gas supplied to the housing unit 101b. The flow rate adjustment unit 125 may be located in the air supply unit 121 or in the exhaust unit 122, as shown in Figure 1. The flow rate adjustment unit 125 is composed of flow rate adjustment members such as a damper or a valve, and is configured to adjust the flow rate of gas in the air supply unit 121. By having the flow rate adjustment unit 125, the second heating unit 120 can adjust the flow rate of gas supplied to the housing unit 101b, thereby contributing to temperature control of the housing unit 101b.

[0029] The exhaust gas processing unit 130 removes harmful substances contained in the gas exhausted from the containment unit 101b and discharges the treated gas to the outside of the processing unit 100. In the illustrated example, the exhaust gas processing unit 130 includes a branch passage 131, a catalyst processing unit 132, and an exhaust passage 133.

[0030] The branch passage 131 connects the second heating unit 120 and the catalyst processing unit 132. The branch passage 131 is composed of a tubular member or the like that branches off from the second heating unit 120 to the exhaust processing unit 130. As shown in Figure 1, the branch passage 131 may be connected to the air supply section 121 of the second heating unit 120, or it may be connected to the exhaust section 122 (see Figure 6). By positioning the branch passage 131 on the exhaust side of the flow rate adjustment unit 125, the gas inflow into the exhaust processing unit 130 can be adjusted by adjusting the gas flow rate of the flow rate adjustment unit 125.

[0031] The catalyst processing unit 132 comprises a heat source and a catalyst, and removes harmful substances contained in the gas by bringing the gas heated by the heat source into contact with the catalyst. The catalyst can be, for example, a solid catalyst containing noble metal nanoparticles (platinum, palladium, rhodium, ruthenium, etc.) on its surface. Such a solid catalyst can remove harmful substances such as carbon monoxide (CO) and hydrocarbons (HC), thereby improving the safety of the gas. The heat source only needs to be able to heat the gas to a temperature at which the catalytic action of the catalyst is exerted, and can be, for example, a heater.

[0032] The discharge passage 133 discharges the gas that has been treated by passing through the catalyst processing unit 132 to the outside of the processing unit 100. The discharge passage 133 is also composed of a tubular member or the like.

[0033] The control unit 140 is configured as a processor that controls each part of the processing unit 100, and specifically includes a CPU (Central Processing Unit) and an MPU (Micro-Processing Unit), etc. Furthermore, the processing unit 100 may have an operation panel connected to the control unit 140 that allows user input operations (not shown).

[0034] The configuration of the processing apparatus 100 is not limited to the example described above and can be modified in various ways. For example, in the processing apparatus 100, it is not essential that the rotation axis C of the shaft portion 102a extends along the horizontal direction; it may be inclined with respect to the horizontal plane. However, in order to effectively obtain the stirring action by gravity in the processing apparatus 100, it is necessary that at least the rotation axis C of the shaft portion 102a is inclined with respect to the vertical direction, and it is preferable that the angle of the rotation axis C of the shaft portion 102a with respect to the horizontal plane is small. Specifically, in the processing apparatus 100, it is preferable that the angle of the rotation axis C of the shaft portion 102a with respect to the horizontal plane is 30° or less. Further modifications of other configurations will be described later.

[0035] [Method for producing granular material] In this embodiment, the method for producing granular material includes, as shown in Figure 4, a step S01 for generating a stirring medium, a step S02 for containing combustible waste, a heating and stirring step S03, and a cooling step S04. The method for producing granular material in this embodiment is carried out using the processing apparatus 100 described above.

[0036] (Step S01: Generation of the stirring medium) In the stirring medium generation step S01, the waste containing used absorbent articles stored in the storage section 101b is heated to a temperature of 180°C to 400°C while being stirred to generate the stirring medium.

[0037] In this embodiment, the waste containing used absorbent articles may also contain other waste in addition to the used absorbent articles. Other waste may include, for example, combustible waste. Combustible waste may include, for example, thermoplastic resins. Combustible waste containing thermoplastic resins may include, in addition to the used absorbent articles mentioned above, used packaging containers (food containers, bottles, etc.), marine debris, etc. The thermoplastic resins contained in the waste are not limited to a specific type, but may include, for example, polyolefins, polyesters, polyacrylic acid, sodium polyacrylate, etc. Furthermore, the waste may contain two or more types of thermoplastic resins.

[0038] Furthermore, the waste in this embodiment may include, for example, non-infectious waste and infectious waste discharged from medical institutions, etc. Examples of medical institutions that discharge waste include hospitals, clinics, hygiene testing laboratories, nursing homes, long-term care medical facilities, and midwifery centers. Infectious waste includes waste containing pathogens that infect or may infect humans, waste to which such pathogens are attached, and waste that may be so. Specifically, examples include used absorbent articles used by patients with infectious gastroenteritis, etc., as well as disposable products such as syringes contaminated with blood or bodily fluids. Non-infectious waste includes waste other than infectious waste (e.g., combustible materials), as well as paper, food waste, non-infectious bandages, cotton wool, gloves, surgical masks, aprons, general used absorbent articles, and other plastic products.

[0039] In this step, the containment section 101b containing the waste is heated to a temperature of 180°C to 400°C by a first heating unit 110 that heats the wall portion 101a of the processing tank 101 and a second heating unit 120 that supplies heated gas to the containment section 101b. This makes it possible to produce a stirring medium in which the waste is slowly carbonized. The heating temperature in this step does not need to be a maximum temperature of 180°C to 400°C, and the maximum temperature may be maintained or may vary within the above temperature range. The time for maintaining a temperature of 180°C to 400°C is not particularly limited as long as granular material can be produced, but as an example, it is 1 hour to 5 hours.

[0040] Furthermore, the heating temperature is preferably between 180°C and 300°C. This suppresses the thermal decomposition of the superabsorbent polymer contained in the used absorbent article. By including the superabsorbent polymer in the stirring medium, the superabsorbent polymer can absorb moisture contained in the combustible waste in the heating stirring step S03 described later, thereby improving the heating efficiency.

[0041] In this step, the material to be processed is stirred by rotating the stirring shaft 102 in the housing section 101b. This crushes the waste to increase heating efficiency and allows the waste to be heated uniformly through stirring. Furthermore, stirring the waste suppresses the binding of waste during the evaporation of water and thermal decomposition processes, and allows for the generation of granular stirring media.

[0042] Furthermore, in this step, after heating to 180°C to 400°C, the housing section 101b may be cooled to 100°C or below if necessary. The cooling process can be carried out in the same manner as in the cooling step S04 described later, so a detailed explanation is omitted. In addition, in this step, the cooling process may be left to cool naturally without active cooling.

[0043] (Combustible waste containment step S02) In the combustible waste containment step S02, combustible waste having a water content of 80% by mass or more is contained in the containment section 101b, which is the internal space of the treatment tank 101. In this step, the agitation medium generated in the agitation medium generation step S01 remains in the containment section 101b.

[0044] (Heating and stirring step S03) In the heating and stirring step S03, a granular stirring medium, generated by heating the waste containing used absorbent materials in the containment section 101b, and the material to be treated, including combustible waste, are stirred while being heated to a temperature between 180°C and 400°C to generate granular material. This stirring medium remains continuously contained in the containment section 101b from the stirring medium generation step S01 until the heating and stirring step S03.

[0045] In this step, the containment section 101b is heated to a temperature of 180°C to 400°C by, for example, a first heating unit 110 that heats the wall portion 101a of the processing tank 101 and a second heating unit 120 that supplies heated gas to the containment section 101b. By heating the temperature to 180°C to 400°C, it is possible to generate recycled material while thermally decomposing the material to be processed and suppressing energy consumption. Another advantage is that it is possible to generate granular material, which is a carbide with a high carbon ratio, by suppressing the volatilization of carbon compounds. In this step, the heating temperature only needs to have a maximum temperature of 180°C to 400°C, and the maximum temperature may be maintained or may vary within the above temperature range. The time for maintaining a temperature of 180°C to 400°C is not particularly limited as long as granular material can be generated, but for example, it is 1 hour to 5 hours.

[0046] Furthermore, the heating temperature is preferably between 180°C and 300°C. This suppresses the thermal decomposition of superabsorbent resins derived from absorbent articles contained in the granular stirring medium. Therefore, when the generated granules are used as a stirring medium in the subsequent heat treatment, the effect of improving heating efficiency due to water absorption can be achieved.

[0047] In this step, the heater 111 of the first heating unit 110 heats the wall portion 101a, thereby heating the housing portion 101b from the outside. Furthermore, in the second heating unit 120, by operating the blower portion 123 and the heating portion 124, gas is exhausted from the housing portion 101b by the exhaust portion 122, the exhausted gas is heated by the heating portion 124, and the heated gas is supplied to the housing portion 101b from the air supply portion 121. As a result, the inside of the housing portion 101b can be directly heated by the heated gas (hot air), allowing the housing portion 101b to be heated efficiently, and as will be described later, the rate of heating can be easily controlled.

[0048] In this step, the material to be processed is stirred by rotating the stirring shaft 102 in the housing section 101b. This crushes the material to be processed, increasing heating efficiency, and allows the material to be heated uniformly through stirring. Furthermore, stirring the material to be processed suppresses the binding of the material during the evaporation of water and thermal decomposition processes, making it easier to generate granular material.

[0049] (Cooling step S04) In the cooling step S04, after the heating and stirring step S03, the containment section 101b is cooled to below 100°C. This cools the generated granular material.

[0050] In this step, for example, cooling gas is supplied from the air supply section 121 of the second heating unit 120 to the containment section 101b by operating the air blower section 123 of the second heating unit 120. The cooling gas can be an inert gas or air, adjusted to a temperature lower than that of the heating and stirring step S03. Specifically, the cooling gas can be obtained by stopping the heating section 124 or by setting the heating section 124 to a temperature lower than that of the heating and stirring step S03 (for example, 100°C or lower). The temperature reached in the containment section 101b in the cooling step S04 is preferably such that the granular material formation status can be checked and the granular material can be collected, and the granular material is in a state of heat storage, for example, preferably between 20°C and 80°C.

[0051] In this step, the material to be processed may also be stirred while cooling by rotating the stirring shaft 102. This makes it possible to suppress viscosity and form finely crushed granular material with small particle size, even if the material to be processed contains a thermoplastic resin that tends to increase in viscosity during the cooling process. Another advantage is that the cooling efficiency can be improved by cooling the material while stirring it.

[0052] (Summary of methods for producing granular materials) The above steps generate granular material. After the cooling step S04, the granular material may be removed from the containment section 101b, or new combustible waste may be placed in the containment section 101b with the granular material remaining, and the generated granular material may be used as a stirring medium to perform the next processing.

[0053] According to the above-described method for producing granular material, combustible waste having a water content of 80% by mass or more is heated and stirred using a granular stirring medium derived from used absorbent articles. As a result, in the heating and stirring step S03, the granular stirring medium penetrates between the wall portion 101a of the treatment tank 101 and the combustible waste, and between the combustible waste particles themselves, preventing the combustible waste from binding to the wall portion 101a and to the combustible waste particles themselves due to moisture. Therefore, since the combustible waste is dispersed and heated uniformly within the containment section 101b, a homogeneous granular material can be produced without performing pretreatment to reduce the water content, such as dehydration. Furthermore, because the stirring medium is granular, it can penetrate into narrow gaps between the combustible waste particles, allowing the aforementioned anti-binding effect to be evenly exerted.

[0054] In addition, the granular agitator can create fine scratches in the combustible waste that serve as starting points for crushing. For example, even when kitchen waste is contained in a thin plastic tare bag, the granular material can break through this thin tare bag and expose the kitchen waste inside. This promotes the crushing of combustible waste and further improves the efficiency of the heat agitation process.

[0055] Furthermore, in this embodiment, the granular stirring medium is produced by a heating and stirring process at a temperature of 180°C to 400°C. At least a portion of this stirring medium is carbonized and can exhibit a heat storage effect. This heat storage effect of the stirring medium can promote the heating of the combustible waste coated on the stirring medium, thereby increasing the heating efficiency. In addition, the increased heating efficiency can reduce the energy consumption of the processing device 100, thereby increasing energy efficiency.

[0056] As described above, the granular material manufacturing method of this embodiment eliminates the need for dewatering and drying processes using separate equipment, even for combustible waste with a moisture content of 80% by mass or more. Recycled material can be produced very easily using a single processing unit 100. Furthermore, as mentioned above, by using a granular stirring medium, efficient heat treatment is possible without the use of combustion aids, further reducing the cost and effort required to produce recycled material.

[0057] Furthermore, in this embodiment, the granular agitation medium is derived from waste containing used absorbent articles, is generated by the same processing device 100 used for processing combustible waste, and is left in the containment section 101b after generation. This minimizes the cost and effort required to prepare the agitation medium, enabling more efficient and simpler processing. It also contributes to the recycling of used absorbent articles.

[0058] In addition, as mentioned above, it is preferable that the stirring medium contains a superabsorbent polymer that has not been thermally decomposed. Figure 5 is a schematic diagram illustrating the effects of a stirring medium containing a superabsorbent polymer. Referring to Figure 5(A), at the start of the process, for example, a stirring medium G1 that does not contain a superabsorbent polymer and a stirring medium G2 that contains a superabsorbent polymer are present around the combustible waste F, and moisture W that has seeped out from the combustible waste F is present over a wide area. Note that in the same figure, for clarity, the stirring medium G1 that does not contain a superabsorbent polymer is shown as a black circle and the stirring medium G2 that contains a superabsorbent polymer is shown as a white circle, but this representation does not reflect the actual appearance. As the process progresses, the stirring medium G2 that contains a superabsorbent polymer absorbs the moisture W that has seeped out around the combustible waste F. Referring to Figure 5(B), this creates a gap around the combustible waste F, allowing heated air to pass through and efficiently heating the combustible waste F. Furthermore, because the moisture W that causes binding is quickly absorbed, binding is effectively suppressed.

[0059] In this way, by including a superabsorbent polymer that has not undergone thermal decomposition in the stirring medium, the heating efficiency of combustible waste with a water content of 80% by mass or more can be further increased, and uniformly heated recycled material can be easily produced without the need for dewatering treatment or the addition of combustion aids.

[0060] [Example of the ratio of the mass of the generated granular material to the mass of the combustible waste] As described above, since the moisture content of the combustible waste to be processed is 80% by mass or more, the mass of the product can be greatly reduced by heating at 180°C to 400°C, which causes the water to evaporate. Specifically, the ratio of the mass of the generated granular material to the mass of the combustible waste before the heating and stirring step S03 is preferably 10% by mass or less, more preferably 8% by mass or less, and even more preferably 5% by mass or less. By setting the ratio of the mass of the generated granular material to the mass of the original combustible waste to 10% by mass or less, the volume of the combustible waste can be greatly reduced, and the storage space required for the generated recycled material can be reduced.

[0061] [Example configuration for granular agitation media] The agitation medium used in the processing is preferably sufficient to accommodate the specifications of the containment section 101b and / or the amount of combustible waste. For example, in the combustible waste containment step S02, it is preferable to contain the combustible waste in the containment section 101b with the agitation medium contained such that its volume exceeds at least a portion of the shaft section 102a. The volume of the agitation medium is determined by referring to Figure 2 and taking the vertical height L of the surface of the agitation medium that has been smoothed along a horizontal plane. The volume of the agitation medium that results in such volume is set according to the position of the agitation shaft 102, but is preferably, for example, 25% or more of the volume of the containment section 101b. By setting the volume of the agitation medium in this way, the effects of the agitation medium, such as promoting crushing, water absorption, and improving heating efficiency, can be more reliably achieved.

[0062] Furthermore, the ratio of the mass of the stirring medium to the mass of the combustible waste before the heating and stirring step S03 is preferably 80% by mass or more. This allows sufficient use of the stirring medium with respect to the combustible waste, and enables the aforementioned effects of the stirring medium, such as promoting crushing, suppressing binding, and absorbing water, to be more reliably exerted. Moreover, from the viewpoint of even more reliably exerting the above-mentioned effects, the ratio of the mass of the stirring medium to the mass of the combustible waste is more preferably 100% by mass or more. The upper limit of the ratio of the mass of the stirring medium to the mass of the combustible waste can be appropriately set in consideration of the processing limit of the containment section 101b, but is preferably 200% by mass or less, and more preferably 180% by mass or less.

[0063] Furthermore, the "covering rate" is defined as the ratio of the area of ​​combustible waste covered by the stirring medium, as viewed from above the containment section 101b 30 seconds after the start of the heating and stirring step S03, to the area of ​​combustible waste as viewed from above the containment section 101b after the containment step S02 and before the start of the heating and stirring step S03. The covering rate is an indicator for evaluating how easily the stirring medium can cover the combustible waste. From the viewpoint of ensuring that the stirring medium can more reliably exert its effects such as promoting crushing, suppressing binding, and absorbing water by quickly covering the combustible waste, the covering rate is preferably 60% or more, more preferably 70% by mass or more. The specific method for calculating the covering rate will be described later in the examples.

[0064] [Example configuration for controlling heating temperature] In the heating and stirring step S03, the heating rate of the containment section 101b can be controlled by the first heating unit 110, the second heating unit 120, and the flow rate adjustment unit 125. By using two heating units, as described above, the temperature inside the containment section 101b can be made uniform, and the number of parameters for controlling the heating temperature can be increased, making it easier to control the heating rate. In the case of a workpiece with a high moisture content, during the process of drying the moisture, the flow rate adjustment unit 125 can be opened by, for example, widening the valve of the flow rate adjustment unit 125 to increase the airflow velocity and accelerate the drying of the workpiece. After the drying of the workpiece has progressed, the airflow velocity can be suppressed, and uniform thermal decomposition can be achieved by coordinating the temperatures of the first heating unit 110, which heats the containment section 101b from the outside, and the second heating unit 120, which heats it from the inside. In this case, the temperature difference between the heating temperatures of the first heating unit 110 and the second heating unit 120 is preferably within plus or minus 20°C, and more preferably within plus or minus 10°C, from the viewpoint of suppressing uneven heating of the workpiece.

[0065] In this embodiment, as a specific method for controlling the heating rate in the heating and stirring step S03, for example, the parameters of the first heating unit 110 and the second heating unit 120 may be kept constant. Alternatively, one parameter of the first heating unit 110 or the second heating unit 120 may be kept constant while the other parameter is changed. Alternatively, the parameters of both the first heating unit 110 and the second heating unit 120 may be changed. Specific parameters for the first heating unit 110 include the set temperature (output) of the heater 111. Specific parameters for the second heating unit 120 include the set temperature (output) of the heating section 124, the output of the blower section 123, and the flow rate of the flow rate adjustment section 125. These controls may be controlled by the control unit 140 based on input operations from an operation panel (not shown), or the control unit 140 may automatically control them based on monitoring results of the temperature of the housing section 101b, etc.

[0066] Furthermore, as a method for monitoring the temperature of the containment section 101b, for example, the temperature of the gas in the exhaust section 122 may be monitored, and the heating rate of the containment section 101b may be controlled based on the monitored temperature. In this example, the second heating unit 120 further includes a temperature sensor such as a thermocouple (not shown) that measures the temperature of the gas placed in the exhaust section 122. Since the gas in the exhaust section 122 is exhausted from the containment section 101b, its temperature reflects the temperature inside the containment section 101b. As a result, even without placing a temperature sensor inside the containment section 101b, the temperature inside the containment section 101b can be measured indirectly by utilizing the configuration of the second heating unit 120. Therefore, even when the object to be processed contains a thermoplastic resin, it is possible to prevent the molten thermoplastic resin from adhering to the temperature sensor, thereby suppressing a decrease in the maintainability of the temperature sensor and a decrease in measurement accuracy.

[0067] Furthermore, from the viewpoint of monitoring the temperature of the containment section 101b with greater accuracy, the temperature of the gas in the supply air section 121 may be monitored in addition to the exhaust air section 122, and the heating rate of the containment section 101b may be controlled based on the temperatures monitored in the exhaust air section 122 and the supply air section 121. In this case, the second heating unit 120 further includes a temperature sensor (not shown) located in the supply air section 121. By calculating the temperature difference between the supply air section 121 and the exhaust air section 122, the temperature rise of the containment section 101b due to the supply of heated gas can be detected. This allows for more accurate control of the heating rate of the containment section 101b.

[0068] [Example configuration for controlling cooling temperature] In the cooling step S04, the temperature of the gas in the exhaust section 122 may also be monitored, and the cooling rate of the containment section 101b may be controlled based on the monitored temperature. This temperature monitoring can be performed by a temperature sensor located in the exhaust section 122 as described above. The cooling rate of the containment section 101b can also be adjusted by the output of the air blower section 123 of the second heating unit 120, etc. For example, from the viewpoint of increasing processing efficiency, the cooling rate is preferably 1°C / min or more, more preferably 5°C / min or more, and to obtain stable granular material, it is preferably 1°C / min or less, more preferably 0.5°C / min or less. In this case as well, the temperature of the gas may also be monitored in the air supply section 121 in addition to the exhaust section 122, and the cooling rate of the containment section 101b may be controlled based on the temperatures monitored in the exhaust section 122 and the air supply section 121.

[0069] [Example configuration for exhaust treatment] In this embodiment, it is preferable to perform exhaust treatment to remove harmful substances contained in the gas exhausted from the containment section 101b. In the example shown in Figure 1, the gas exhausted from the containment section 101b may be the gas exhausted by the exhaust section 122 of the second heating unit 120. The exhaust treatment is performed in at least one step selected from, for example, the stirring medium generation step S01, the heating and stirring step S03, and the cooling step S04. In the exhaust treatment of this embodiment, gas containing water vapor is generated as the material to be treated evaporates or is thermally decomposed, and the excess gas in the exhaust section 122 flows into the branch passage 131, where harmful substances such as carbon monoxide (CO) are removed in the catalyst processing section 132. This makes it possible to increase the safety of the gas discharged to the outside of the processing device 100 from the discharge passage 133 and realize a heat treatment with a low environmental impact.

[0070] [Example of a treatment tank configuration] In this embodiment, as illustrated in Figure 2, it is preferable that the height H2 of the shaft portion 102a in the vertical direction from the bottom surface 101c of the storage portion 101b is 1 / 2 or less of the maximum vertical height H1 of the storage portion 101b. This makes it easier to store the stirring medium so that its volume exceeds at least a portion of the shaft portion 102a, and also makes it easier to store a sufficient amount of new combustible waste in the storage portion 101b. The height H2 of the shaft portion 102a is the height of the rotation axis C of the shaft portion 102a. Furthermore, from the viewpoint of more effectively exhibiting the above effects, the height H2 is preferably 1 / 3 or less of the maximum height H1.

[0071] [Modified version of the first heating unit] The first heating unit 110 is not limited to the configuration described above. As illustrated in Figures 6 and 7, the first heating unit 110 may also be configured to heat the inside of the wall portion 101a with gas.

[0072] The first heating unit 110 shown in Figures 6 and 7 can heat the wall portion 101a by supplying heated gas into the wall portion 101a. In this example, the wall portion 101a has a space portion 101d that diffuses the supplied gas. The space portion 101d is configured to conduct heat to the inner surface of the wall portion 101a, and may be, for example, a space formed inside the wall portion 101a, or a tubular member or the like arranged inside the wall portion 101a. The arrangement of the space portion 101d is not particularly limited, but it is preferable that it be arranged over a wide area of ​​the wall portion 101a, and more preferably that it be arranged over the entire wall portion 101a.

[0073] In the example shown in Figures 6 and 7, the first heating unit 110 includes an in-wall air supply section 112, an in-wall exhaust section 113, a blower section 114, and a heating section 115. In this example, the first heating unit 110 operates the blower section 114 to exhaust gas from the space 101d via the in-wall exhaust section 113, heats the exhausted gas with the heating section 115, and supplies the heated gas from the in-wall air supply section 112 to the space 101d. Thus, the first heating unit 110 constitutes a hot air circulation type heating unit. The gas used in the first heating unit 110 is not particularly limited and may be air, an inert gas such as nitrogen, or the like.

[0074] The wall-mounted air supply unit 112 supplies gas to the space 101d inside the wall 101a. In this embodiment, the wall-mounted air supply unit 112 is configured as a gas passage connecting the space 101d and the heating unit 115. The wall-mounted air supply unit 112 is composed of one or more tubular members, for example, a tubular member connected to the space 101d.

[0075] The wall-mounted exhaust section 113 exhausts gas from the space 101d inside the wall section 101a. In this embodiment, the wall-mounted exhaust section 113 is configured as a gas passage connecting the air blower section 114 and the space 101d. The wall-mounted exhaust section 113 is composed of one or more tubular members, including, for example, a tubular member connected to the space 101d.

[0076] The air blower 114 blows gas into the wall-mounted air supply 112. The air blower 114 is composed of a blower such as a fan, blower, or compressor. In the example shown in Figure 6, the air blower 114 is located on the exhaust side of the heating unit 115, but it may also be located on the air supply side.

[0077] The heating unit 115 heats the supplied gas. The heating unit 115 is composed of a heater, and from the viewpoint of facilitating temperature control, it is preferably composed of an electric heater. The heating method, installation position, and other configurations of the heater constituting the heating unit 115 can be determined in various ways depending on the configuration of the processing tank 101 and the properties of the material to be processed.

[0078] Furthermore, the first heating unit 110 may have other configurations as needed. In the example shown in Figure 6, the first heating unit 110 further includes a first valve member 116 that can take in outside air and a second valve member 117 that can exhaust air. This allows for efficient cooling by the first heating unit 110 in the cooling step S04.

[0079] With the first heating unit 110 configured as described above, the heated gas can heat a wide area of ​​the inner surface of the wall portion 101a, and even if the volume of the storage portion 101b is increased, the storage portion 101b can be heated efficiently. Furthermore, by making the first heating unit 110 a circulating heating unit, waste heat can be recovered and energy efficiency can be increased. Therefore, with this configuration, energy consumption can be reduced and the volume of the storage portion 101b can be increased, further improving the energy efficiency of the process.

[0080] [Modified version of the second heating unit] The arrangement of the heating section 124 and the air blower section 123 in the second heating unit 120 is not limited to the example in Figure 1. As illustrated in Figure 6, the air blower section 123 may be positioned on the exhaust side of the heating section 124.

[0081] [Example of Oxygen Supply Unit Configuration] Furthermore, as illustrated in Figure 6, the processing apparatus 100 may have an oxygen supply unit 150 that supplies oxygen to the gas exhausted from the containment unit 101b. In the example shown in Figure 6, the oxygen supply unit 150 is connected to the branch line 131. The gas exhausted from the containment unit 101b may be the gas exhausted by the exhaust section 122 of the second heating unit 120 and introduced into the branch line 131. By supplying oxygen to the gas exhausted from the containment unit 101b in at least one step selected from the generation step S01, heating and stirring step S03, and cooling step S04 of the second heating unit 120, carbon monoxide (CO) can be oxidized to produce carbon dioxide (CO2), thereby suppressing the emission of harmful carbon monoxide. Note that the oxygen supply unit 150 is not limited to the example where it is connected to the branch line 131, but may also be connected to the exhaust section 122 of the second heating unit 120.

[0082] The specific configuration of the oxygen supply unit 150 includes, for example, a fan for taking in outside air and a valve member such as a valve for adjusting the intake of outside air. This allows outside air containing oxygen to be supplied to the exhaust gas. Alternatively, the oxygen supply unit 150 may include a container for storing oxygen gas instead of a fan for taking in outside air, and supply oxygen gas via the valve member. The amount of oxygen supplied by the oxygen supply unit 150 can be appropriately adjusted to an amount that reduces carbon monoxide without reducing the carbon ratio of the particulate matter.

[0083] [Example of granular material composition] In the method for producing granular material according to the above embodiment, as described above, granular material with a particle size of 10 μm to 5 cm is produced by heat-treating combustible waste. The composition of this granular material will be described below.

[0084] The carbon content of the granular material is preferably 30% by mass or more, more preferably 40% by mass or more, and even more preferably 50% by mass. This allows the granular material to be effectively utilized as a recycled material with the functions of charcoal. Furthermore, by using such granular material as a stirring medium in the heating and stirring treatment of waste, the heat storage effect unique to charcoal can be exhibited, improving heating efficiency and energy efficiency. The carbon content of the granular material can be measured using an organic element analyzer.

[0085] The calorific value of the granular material is preferably 20 MJ / kg or more, more preferably 22.5 MJ / kg or more, and even more preferably 25 MJ / kg. This makes it possible to obtain granular material that is easily combustible and usable as fuel. The calorific value of the granular material can be the total calorific value measured using a calorimeter such as a cylinder calorimeter, in accordance with JIS M8814:2003.

[0086] The moisture content of the granular material is preferably 10% by mass or less, more preferably 3% by mass or less, and even more preferably 1% by mass or less. This allows for the production of granular material that is sufficiently dried and easily combustible. The moisture content is measured according to the measurement procedure for nitrogen-stream drying loss measurement described in JIS M8812:2004.

[0087] The granular material may contain sodium (Na). This makes it possible to obtain granular material containing inorganic components that are desirable for use as fertilizers or soil conditioner compositions. The Na content of the granular material is preferably 1.0% by mass or more, more preferably 1.5% by mass or more, preferably 10.0% by mass or less, and more preferably 8.0% or less. Granular material containing Na can be obtained, for example, by processing waste containing absorbent articles containing superabsorbent polymers containing sodium salts.

[0088] The granular material may contain calcium (Ca). This makes it possible to obtain granular material containing inorganic components that are desirable for use as fertilizers or soil conditioner compositions. The Ca content of the granular material is preferably 1.0% by mass or more, more preferably 1.5% by mass or more, preferably 10.0% by mass or less, and more preferably 8.0% or less. Granular material containing Ca can be obtained, for example, by processing waste containing absorbent articles that contain calcium carbonate.

[0089] The oxygen index of the granular material is preferably less than 29%, more preferably less than 27%. This allows for the production of granular material that is easily combustible and highly useful as a fuel. The oxygen index is the minimum oxygen concentration (%), volume fraction, of a mixed gas of oxygen and nitrogen at 23°C ± 2°C required for the sample to maintain flammable combustion under predetermined conditions. Specifically, it is measured according to the oxygen index measurement procedure described in JIS K7201-2:2007.

[0090] From the viewpoint of increasing the carbon ratio, the hydrogen ratio of the granular material is preferably 15% by mass or less, preferably 12% by mass or less, and more preferably 10% by mass or less. The hydrogen ratio of the granular material can be measured using an organic elemental analyzer.

[0091] From the viewpoint of increasing flammability, the oxygen ratio of the granular material is preferably 15% by mass or more, more preferably 17% by mass or more, and from the viewpoint of increasing the carbon ratio, it is preferably 35% by mass or less, more preferably 33% by mass or less. The oxygen ratio of the granular material can be measured by an organic element analyzer.

[0092] Furthermore, since the granular material is at least partially carbonized, it is preferable that it has a fine uneven surface structure, and more preferably, it has fine pores formed on its surface. This is thought to enable physical adsorption function at the fine unevenness and pores. The fine uneven surface structure and pores should be a structure that can be confirmed from an image of the granular material magnified 1000 to 1500 times.

[0093] Furthermore, it is preferable that the granular material has a deodorizing function, particularly against excretory odors such as ammonia, acetic acid, and indole, by physically adsorbing odor components through its fine irregularities and pores. In this case, the granular material can be used as a deodorant.

[0094] In addition, it is preferable that the granular stirring medium also has a fine uneven surface structure and / or fine pores formed on its surface. In this embodiment, the granular stirring medium is also produced by a heating and stirring treatment at 180°C to 400°C, similar to the granular material, so a fine uneven surface structure and pores can be formed on its surface during the carbonization process. For this reason, it is preferable that the granular stirring medium also has a deodorizing function. This allows for the suppression of odor generation from the combustible waste by the deodorizing function of the granular stirring medium, even when a long time is required from the combustible waste containment step S02 to the heating and stirring step S03.

[0095] Because the granular material contains a large amount of carbon and is easily combustible, it can be used as part of a fuel. As a fuel, for example, it can be used as a substitute material for fossil resources (such as coal). Furthermore, the granular material can be effectively utilized as, for example, a composition for paper, a composition for fibers, a composition for soil improvement, a composition for water treatment, a fuel, a fertilizer, a building material such as an insulating material, an adsorbent, an antidote, a deodorant, etc.

[0096] Furthermore, a molded body can be obtained by forming the granular material of this embodiment into pellets. Such a molded body is commonly used as fuel, fertilizer, etc., and can be suitably used as a substitute for conventionally used materials. The dimensions of the molded body can be set appropriately depending on the application, but for example, the maximum dimensions can be 5 mm or more and 50 mm or less. The molded body can be manufactured, for example, by a molding machine such as a pelletizer.

[0097] <Second Embodiment> In the method for manufacturing granular material according to the first embodiment described above, the stirring medium generated in the stirring medium generation step S01 was left in the containment section 101b while the combustible waste was heated and stirred. However, the method is not limited to this, and the stirring medium may be added from an external source. In the following embodiments, components similar to those in the first embodiment described above are denoted by the same reference numerals and their descriptions are omitted.

[0098] As shown in Figure 8, the method for manufacturing granular material according to the second embodiment of the present invention includes a stirring medium containment step S05, a combustible waste containment step S02, a heating and stirring step S03, and a cooling step S04. In this embodiment, all steps except the stirring medium containment step S05 are the same as those in the first embodiment, so the stirring medium containment step S05 will be described in detail. The method for manufacturing granular material in this embodiment is carried out using the processing apparatus 100 described in the first embodiment.

[0099] In the agitation medium containment step S05, granular agitation medium is contained in the containment section 101b before the combustible waste containment step S02. The agitation medium may be generated by a heating device separate from the processing device 100, or it may be generated in the processing device 100 and then discharged outside the containment section 101b. Furthermore, it is preferable that the agitation medium is generated by agitating waste containing used absorbent articles while heating it to 180°C or higher and 400°C or higher, as described in the agitation medium generation step S01.

[0100] As a result, in the heating and stirring step S03, similar to the first embodiment, the granular stirring medium can prevent the combustible waste from binding to each other and to the wall portion 101a. Furthermore, the granular stirring medium can promote the crushing of the combustible waste, and the heat-retaining stirring medium can improve heating efficiency. These features enable the efficient and simple production of recycled material from combustible waste.

[0101] <Third Embodiment> Next, a third embodiment of the present invention will be described. In this embodiment, descriptions common to the first and second embodiments described above will be omitted as appropriate.

[0102] As described above, the granular material can be used as fuel. Therefore, in this embodiment, as schematically shown in Figure 9, we will describe a method of producing granular material G using food waste discharged from a facility 300 that utilizes the generated energy, as combustible waste, in which energy is generated in an energy generation device 200 using granular material G as fuel.

[0103] The granular material G is used in a form suitable for use as fuel for the energy generation device 200. For example, the fuel derived from the granular material G may be the granular material G itself, or it may be a solid fuel produced by molding the granular material G.

[0104] The solid fuel may be in the pellet form described above, or in any other form such as briquettes or tablets. In addition to the granular material G, the solid fuel may also contain binders for molding, additives, and other materials (RPF or wood chips). However, the content of the granular material G in the solid fuel is preferably 5% by mass or more, and more preferably 10% by mass or more.

[0105] The energy generation device 200 can be any device capable of generating energy that can be supplied to the facility 300 described later, using the fuel derived from the granular material G described above. Examples include boilers, gasifiers, stoves (e.g., pellet stoves), power generation devices, etc. In this embodiment, the "energy generation device 200" is not limited to a single device, but also includes a configuration in which multiple devices cooperate to generate energy.

[0106] Although Figure 9 shows an example where the energy generation device 200 is installed outside the facility 300, it may also be installed inside the facility 300 and supply energy to other devices within the facility 300.

[0107] The energy generated by the energy generation device 200 can include electricity, energy derived from gas fuel, thermal energy, etc. The form of thermal energy supply can be appropriately determined according to the configuration of the energy generation device 200 and the configuration of the devices that utilize energy in the facility 300, and examples include heated gas such as hot air, hot water, etc. As an example, the energy generated by the energy generation device 200 may include thermal energy generated by a boiler, in which case the thermal energy is supplied, for example, as hot water.

[0108] Facility 300 is a facility that utilizes energy generated using fuel derived from granular material G and also generates food waste. Examples of facilities 300 include facilities operated by food-related businesses and facilities operated by agricultural businesses.

[0109] Examples of facilities operated by food-related businesses include food manufacturing and processing plants, stores operated by food wholesalers and retailers, restaurants, and facilities operated by businesses that provide meals. The forms of energy use in these facilities are not particularly limited, but include, for example, the use of electricity and the use of thermal energy in processing involving heating and heating equipment.

[0110] Furthermore, examples of food waste generated from facilities operated by food-related businesses include processing residues from food manufacturing and processing plants, processing scraps and unsold goods from facilities operated by food wholesalers and retailers, and cooking scraps and leftovers from facilities operated by restaurants and businesses that provide meals.

[0111] Furthermore, facilities operated by agricultural businesses include, for example, agricultural production facilities, processing and / or storage facilities, and distribution facilities. Examples of agricultural production facilities include greenhouses, hothouses, and livestock barns. Examples of processing and / or storage facilities include rice milling plants, drying facilities, and refrigeration / freezing facilities. Examples of distribution facilities include sorting plants, collection centers, and direct sales outlets. The forms of energy utilization in these facilities are not particularly limited, but include, for example, the use of electricity and the use of thermal energy in processing involving heating and in heating equipment.

[0112] Furthermore, examples of food waste generated from facilities operated by agricultural businesses include crop scraps, processing waste, rice bran, rice husks, damaged crops, and unsold products.

[0113] The food waste discharged from facility 300 is, as at least a portion of the combustible waste having a moisture content of 80% by mass or more as described in the first embodiment, contained in the containment section 101b of the processing device 100 in containment step S02 and used in the production of granular material G.

[0114] As described above, according to this embodiment, carbon-derived energy fixed as granular material G by the processing device 100 is supplied to the facility 300, and food waste discharged from the facility 300 is used as raw material for the granular material. This reduces the amount of greenhouse gases such as CO2 emitted from the facility 300, and also reduces the amount of greenhouse gases emitted when processing the food waste discharged from the facility 300. Therefore, according to this embodiment, not only is waste recycled, but the amount of greenhouse gases emitted from the facility that is the source of the waste is also reduced, and an even more environmentally friendly recycling process can be achieved. In addition, resources can be circulated in the region to which the processing device 100, energy production device 200, and facility 300 belong, and the effective use of resources can be promoted.

[0115] <Fourth Embodiment> Next, a fourth embodiment of the present invention will be described. In this embodiment, descriptions common to the above embodiments will be omitted as appropriate.

[0116] In the method for manufacturing granular material according to the fourth embodiment of the present invention, from the viewpoint of further reducing greenhouse gas emissions related to the recycling process, the power source of the processing apparatus 100 for manufacturing the granular material includes energy derived from renewable energy. In this case, all or part of the power source of the processing apparatus 100 for manufacturing the granular material may be energy derived from renewable energy.

[0117] Renewable energy sources are energy sources obtained from the natural environment that can be used indefinitely without being depleted, and include, for example, solar, wind, hydro, geothermal, and biomass. Energy derived from renewable sources includes electricity from solar power generation, wind power generation, hydroelectric power generation, geothermal power generation, thermal energy from hot water used in geothermal power generation, and biomass power generation.

[0118] In this embodiment, the renewable energy-derived energy preferably includes electricity generated by solar power. Solar power generation equipment offers a high degree of flexibility in terms of installation location and can be installed at a lower cost compared to other renewable energy-related equipment. In this way, by using electricity generated by solar power, renewable energy-derived energy supply equipment can be introduced relatively easily.

[0119] Furthermore, in this embodiment, it is preferable that the electricity generated by solar power includes stored electricity generated by solar power. For storage, an energy storage system including a battery can be used. This allows, for example, the electricity generated by solar power during the day to be stored and supplied to the processing unit 100 at night to operate the processing unit 100. Alternatively, by using stored electricity, the processing unit 100 can be supplied with power stably regardless of the weather. As a result, the processing unit 100 can stably utilize solar power regardless of the weather or time of day.

[0120] As described above, according to this embodiment, at least a portion of the power source required for the operation of the processing device 100 can be derived from renewable energy sources that do not emit greenhouse gases such as CO2. Therefore, greenhouse gas emissions related to the operation of the processing device 100 can be reduced, and greenhouse gas emissions in the overall waste recycling process can be reduced.

[0121] In addition, this embodiment can be implemented in combination with the third embodiment. This allows for a reduction in greenhouse gas emissions related to the discharge of food waste, as well as a reduction in greenhouse gas emissions related to the operation of the processing device 100. Therefore, greenhouse gas emissions related to the recycling process can be reduced more reliably, further reducing the environmental burden.

[0122] <Additional Note> Although embodiments of the present invention have been described above, the present invention is not limited to the embodiments described above, and various modifications can be made without departing from the spirit of the present invention.

[0123] For example, in the second embodiment described above, an example was described in which the combustible waste containment step S02 is performed after the combustible waste containment step S05. However, the order of these steps is not limited, and the combustible waste containment step S02 may be followed by the combustible waste generation step S01.

[0124] Alternatively, for example, the component concentration of the gas exhausted from the containment section 101b may be monitored in at least one step selected from the stirring medium generation step S01, the heating and stirring step S03, and the cooling step S04. In this example, the processing apparatus 100 has a gas component concentration measuring device located in the exhaust section 122 or the exhaust processing section 130. Examples of gas component concentrations to be measured include oxygen concentration, carbon monoxide concentration, carbon dioxide concentration, and the concentrations of other harmful substances. This allows information about the composition of the exhausted gas to be obtained, which can be used for process control and reduction of harmful substance emissions.

[0125] The cooling step S04, in which the inside of the housing section 101b is cooled by the blower section 123, is not mandatory; for example, the housing section 101b may be cooled naturally.

[0126] The exhaust gas treatment is not limited to the examples described above; for example, it may be performed by a device other than the treatment device 100.

[0127] The configuration of the processing apparatus 100 used for manufacturing granular material is not limited to the above example. For example, the first heating unit may have a heater installed inside the wall portion 101a, or it may have a configuration in which the inside of the wall portion 101a is heated by a heated liquid. The second heating unit may also perform exhaust treatment without circulating the gas exhausted from the containment portion 101b. [Examples]

[0128] Using the apparatus described in Figure 1 in the above-described embodiment, a granular material manufacturing process according to an embodiment of the first embodiment of the present invention was carried out. As shown in Table 1, the first heating unit 110 was an under-hearth heating unit using a heater (heating from the bottom surface 101c), and the second heating unit 120 was an exhaust gas circulation type heating unit.

[0129] [Table 1]

[0130] First, to generate granular agitation media, 5 kg of unused disposable diapers were mixed with 5 kg of water to prepare a 10 kg sample of used disposable diapers. The moisture content of this simulated used diaper was 50% by mass. In addition, 20 kg of previously generated granular agitation media was prepared. These were placed in the containment section of the processing device and subjected to a heating and stirring treatment, reaching a temperature of 225°C. After that, a cooling treatment was performed to generate granular agitation media with a particle size of 10 μm to 5 cm. The energy consumption for the heating and stirring treatment was 9.5 kWh / kg. The ratio of the mass of the generated agitation media to the mass of the sample before heating (indicated as "residue rate" in Table 1) was 24.3% by mass.

[0131] Next, granular material was generated from combustible waste. 16.1 kg of kitchen waste was prepared as combustible waste, and 20 kg of granular agitator derived from disposable diapers was prepared as the agitator. The moisture content of the kitchen waste was approximately 90% by mass. These were placed in the containment section of the processing device and subjected to heating and stirring treatment, reaching a temperature of 225°C. After cooling, granular material with a particle size of 10 μm to 5 cm was generated. The energy consumption for the heating and stirring treatment was 6.0 kWh / kg. The ratio of the mass of the generated granular material to the mass of the combustible waste before the heating and stirring step S03 (residue rate) was 3.7% by mass.

[0132] Furthermore, the ratio of the area of ​​combustible waste covered by the stirring medium, as viewed from above the containment section 30 seconds after the start of the heating and stirring step, to the area of ​​combustible waste viewed from above the containment section after the containment step but before the start of the heating and stirring step (covering rate), was approximately 60%. This indicates that the combustible waste is sufficiently covered by the granular stirring medium immediately after heating and stirring.

[0133] The coverage rate was calculated as follows: After the combustible waste was placed inside the container and before the heating and stirring step began, an image including the entire combustible waste was taken from above the container. Subsequently, 30 seconds after the start of the heating and stirring step, an image was taken from above the container with the same field of view. The coverage rate of the stirring medium in the images taken before the start of the heating and stirring step and 30 seconds later was calculated by image analysis. The coverage rate of the stirring medium was calculated using the following formula. Coverage (%) = Area covered by the stirring medium in the image 30 seconds after the start of the heating and stirring step / Area of ​​the material to be treated (combustible waste) in the image before the start of the heating and stirring step × 100

[0134] As described above, it was found that granular material can be easily produced from kitchen waste with a moisture content of 80% or more by mass using a stirring medium derived from simulated used disposable diapers. Furthermore, compared to processing simulated used disposable diapers with a moisture content of 50% by mass, the energy consumption in processing kitchen waste was lower, indicating high energy efficiency. [Explanation of Symbols]

[0135] 100… Processing equipment 101... Processing tank 101a...Wall part 101b... Containment Unit 102…Agitation shaft 102a...Wing section 102b…Shaft part 110...First heating unit 120...Second heating unit

Claims

1. A device for producing granular material using combustible waste having a water content of 80% by mass or more, The wall section, A containment section, surrounded by a wall, capable of accommodating a material to be processed, which includes a granular agitation medium produced by heating waste containing used absorbent materials, and the aforementioned combustible waste. The aforementioned housing includes a stirring shaft that rotates to agitate the material to be processed, A processing tank having, A first heating unit for heating the wall portion, A second heating unit heats the gas exhausted from the aforementioned storage unit and supplies it to the aforementioned storage unit, Control unit and It is equipped with, The control unit, The first heating unit and the second heating unit heat the housing to 180°C to 400°C, and the stirring shaft is rotated in the housing to stir the material to be processed. A device for manufacturing granular materials.

2. The aforementioned used absorbent article contains a superabsorbent polymer. The apparatus for producing granular material according to claim 1.

3. The stirring medium includes the superabsorbent resin that has not been thermally decomposed. The apparatus for producing granular material according to claim 2.

4. The carbon content of the granular material is 30% by mass or more. The apparatus for producing granular material according to claim 1 or 2.

5. The stirring shaft is It has a shaft portion that can rotate about a rotation axis extending in a direction intersecting the vertical direction, and a plurality of blade portions provided on the outer circumferential surface of the shaft portion at intervals along the rotation axis, The apparatus for producing granular material according to claim 1 or 2.

6. The height of the shaft portion in the vertical direction from the bottom surface of the housing is 1 / 2 or less of the maximum vertical height of the housing. The apparatus for producing granular material according to claim 5.

7. The aforementioned combustible waste includes food waste, The apparatus for producing granular material according to claim 1 or 2.

8. The granular material is used as fuel. The aforementioned food waste includes food waste discharged from facilities that utilize energy generated using fuel derived from the aforementioned granular material. The apparatus for producing granular material according to claim 7.

9. The fuel derived from the granular material includes solid fuel produced by molding the granular material. The apparatus for producing granular material according to claim 8.

10. The energy generated using the fuel derived from the granular material includes the thermal energy generated in the boiler. The apparatus for producing granular material according to claim 8.

11. The power source of the aforementioned manufacturing apparatus includes energy derived from renewable energy sources. The apparatus for producing granular material according to claim 1 or 2.

12. The aforementioned renewable energy sources include electricity generated from solar power, The apparatus for producing granular material according to claim 11.

13. The aforementioned solar power generation includes electricity stored from solar power generation. The apparatus for producing granular material according to claim 12.

14. A method for producing granular material using combustible waste having a water content of 80% by mass or more, The combustible waste containment step involves containing combustible waste having a water content of 80% by mass or more in the containment section, which is the internal space of the treatment tank. The process includes a heating and stirring step in which a granular stirring medium is generated by heating waste containing used absorbent articles within the aforementioned containment section, and a material to be treated, including the combustible waste, is heated to a temperature of 180°C to 400°C while stirring to generate granular material. In the aforementioned heating and stirring step, The first heating unit heats the wall portion of the processing tank, and the second heating unit heats the gas exhausted from the containment and supplies it to the containment, thereby heating the containment to 180°C to 400°C, and, The material to be processed is stirred by rotating the stirring shaft, which has a shaft portion that can rotate about a rotation axis extending in a direction intersecting the vertical direction, and a plurality of blade portions provided at intervals along the rotation axis on the outer surface of the shaft portion, within the housing. In the step of containing the combustible waste, the combustible waste is contained in the containment section with the stirring medium contained such that the volume of the stirring medium exceeds at least a portion of the shaft portion. A method for producing granular material.

15. The ratio of the mass of the generated granular material to the mass of the combustible waste before the heating and stirring step is 10% by mass or less. A method for producing granular material according to claim 14.

16. The ratio of the mass of the stirring medium to the mass of the combustible waste before the heating and stirring step is 80% by mass or more. A method for producing granular material according to claim 14 or 15.

17. The further step of generating the stirring medium by heating the waste, including the used absorbent article contained in the containment section, to 180°C or more and 400°C or less, prior to the step of containing the combustible waste, A method for producing granular material according to claim 14 or 15.

18. In the step of generating the stirring medium, the generated stirring medium is continuously contained in the containment unit until the heating and stirring step, A method for producing granular material according to claim 17.

19. The further step includes, before the heating and stirring step, a step of containing the stirring medium in the containing section. A method for producing granular material according to claim 14 or 15.

20. The ratio of the area of ​​the combustible waste covered by the stirring medium, as viewed from above the containment section 30 seconds after the start of the heating and stirring step, to the area of ​​the combustible waste as viewed from above the containment section 30 seconds after the start of the heating and stirring step, is 60% or more. A method for producing granular material according to claim 14 or 15.

Images