Waste treatment system

Abstract

To provide a waste treatment system that can reduce a treatment cost of wastes with low water content.SOLUTION: A waste treatment system include a reformer for hydrolysis of a waste in a condition of suppression of melanoidin formation, a microorganism reactor for converting a reformate including at least a solid among the waste hydrolyzed by the reformer to lower molecular weight by microorganisms, and a separation unit provided between the reformer and the microorganism reactor for separation of reaction inappropriate matters that are inappropriate to lower molecular weight conversion by the microorganism in the microorganism reactor from the reformate.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to waste treatment systems. [Background technology]

[0002] Patent Document 1 describes an organic waste treatment device that treats organic waste, including organic wastewater and solid waste, such as excess sludge from sewage treatment plants, food waste such as kitchen garbage, livestock waste, etc. In this treatment device, the organic waste is decomposed into soluble low-molecular-weight organic matter, followed by solid-liquid separation, and the separated liquid is subjected to methane fermentation to produce biogas, and the separated solid is composted to produce fertilizer, thereby treating the organic waste. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 4864339 Summary of the Invention [Problem to be solved by the invention]

[0004] However, when treating waste with a lower moisture content than the organic waste shown in Patent Document 1, such as municipal waste, even if the waste is hydrolyzed, most of the treated product remains solid, resulting in a low amount of biogas produced by the treatment device of Patent Document 1. Furthermore, although not only fertilizer but also fuel can be produced from the separated solid, producing biogas brings in greater profits than producing fertilizer or fuel, so there was a risk that the cost of treating waste using the treatment device of Patent Document 1 would be high.

[0005] In view of the above circumstances, an object of at least one embodiment of the present disclosure is to provide a waste treatment system that can reduce the cost of treating waste with a low moisture content. [Means for solving the problem]

[0006] In order to achieve the above-mentioned objectives, the waste treatment system of the present disclosure comprises a modification device that hydrolyzes waste under conditions that suppress the production of melanoidins, a microbial reaction device that uses microorganisms to reduce the molecular weight of the modified material, which contains at least solids from the waste hydrolyzed in the modification device, and a separation device between the modification device and the microbial reaction device that separates unsuitable materials for reduction in molecular weight by the microorganisms from the modified material.

[0007] The waste treatment system according to the present disclosure also includes a first reforming device and a second reforming device, and is equipped with a reforming device that hydrolyzes waste, a solid-liquid separation device that separates the waste material hydrolyzed in the first reforming device into solid and liquid, a microbial reaction device that uses microorganisms to reduce the molecular weight of the reformed material containing at least solids from the waste hydrolyzed in the reforming device, and a separation device between the second reforming device and the microbial reaction device that separates unsuitable materials for reduction to molecular weight by the microorganisms from the reformed material, and the second reforming device hydrolyzes only the solids separated in the solid-liquid separation device. [Effects of the Invention]

[0008] According to the waste treatment system of the present disclosure, hydrolyzed waste can be broken down into smaller molecules by microorganisms to produce valuable materials without solid-liquid separation, so even waste with a low moisture content can be treated at low cost. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a schematic diagram illustrating the configuration of a waste treatment system according to a first embodiment of the present disclosure. [Figure 2] 1 is a schematic diagram showing an example of the configuration of a reforming device in a waste treatment system according to a first embodiment of the present disclosure. [Figure 3] FIG. 3 is a schematic diagram showing another example of the configuration of the reforming device of the waste treatment system according to the first embodiment of the present disclosure. [Figure 4]FIG. 10 is a schematic diagram showing a part of yet another example of the configuration of the reforming device of the waste treatment system according to the first embodiment of the present disclosure. [Figure 5] FIG. 10 is a schematic diagram illustrating the configuration of a waste treatment system according to a second embodiment of the present disclosure. [Figure 6] FIG. 10 is a schematic diagram illustrating a configuration of a modified example of the waste treatment system according to the second embodiment of the present disclosure. [Figure 7] FIG. 10 is a schematic diagram illustrating the configuration of a waste treatment system according to a third embodiment of the present disclosure. [Figure 8] FIG. 10 is a diagram showing an example of spectrum data acquired by a near-infrared sensor in a waste treatment system according to a third embodiment of the present disclosure. [Figure 9] FIG. 10 is a diagram showing spectral data of a plurality of modified products with different contents of unsuitable substances for reaction in a waste treatment system according to a third embodiment of the present disclosure. [Figure 10] FIG. 10 is a diagram showing spectral data of several modified products with different concentrations of unsuitable substances for reaction in a waste treatment system according to a third embodiment of the present disclosure. [Figure 11] 10 is a calibration curve of the concentration of unsuitable substances for reaction in the modified product, used in the waste treatment system according to the third embodiment of the present disclosure. [Figure 12] FIG. 10 is a schematic diagram illustrating the configuration of a waste treatment system according to a fourth embodiment of the present disclosure. [Figure 13] FIG. 10 is a schematic diagram illustrating a configuration of a portion of a modified example of a waste treatment system according to a fourth embodiment of the present disclosure. [Figure 14] FIG. 10 is a schematic diagram illustrating the configuration of a waste treatment system according to a fifth embodiment of the present disclosure. [Figure 15] FIG. 10 is a schematic diagram illustrating the configuration of a waste treatment system according to a sixth embodiment of the present disclosure. [Figure 16] FIG. 10 is a schematic diagram illustrating a configuration of a modified example of a waste treatment system according to the sixth embodiment of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0010] A waste treatment system according to an embodiment of the present disclosure will be described below with reference to the drawings. The embodiment shows one aspect of the present disclosure, and is not intended to limit the present disclosure. Any modification can be made within the scope of the technical concept of the present disclosure.

[0011] (Embodiment 1) <Configuration of waste treatment system according to embodiment 1 of the present disclosure> As shown in Figure 1, a waste treatment system 1 according to a first embodiment of the present disclosure includes a reformer 2 that hydrolyzes waste, such as municipal waste, in the presence of water or steam, and a microbial reaction device 3 that uses microorganisms to convert the reformed product hydrolyzed in the reformer 2 into smaller molecules. Municipal waste, cited as an example of waste, is characterized by being primarily composed of food waste, paper waste, and plastic waste, containing small amounts of metals and having a relatively low moisture content. The waste treated by the waste treatment system 1 is not limited to municipal waste; waste with a higher moisture content than municipal waste, such as sludge generated by treating wastewater from factories and agricultural waste, can also be treated by the waste treatment system 1.

[0012] The reformer 2 receives waste directly from, for example, a waste collection vehicle or a plant, and batchwise hydrolyzes the waste using steam. Specifically, it is a batch-type reformer equipped with a housing 10 including an inlet 11 through which the waste is introduced and an outlet 12 through which the reformed product is discharged. The inlet 11 and the outlet 12 are provided with on-off valves 18 and 19, respectively, and the housing 10 can be sealed by closing the on-off valves 18 and 19. The hydrolysis of the waste in the reformer 2 may be wet hydrolysis, in which steam contacts the waste to heat it, or dry hydrolysis, in which steam does not contact the waste but indirectly heats it. In the case of dry hydrolysis, the water in the waste within the housing 10 evaporates to form steam, and the waste within the housing 10 is uniformly heated by the steam. Furthermore, moisture is required for hydrolysis, and this moisture is supplied by the steam adhering to the surface of the waste. Although FIG. 1 shows one reformer 2, it may be configured such that multiple reformers 2 are connected in series, multiple reformers 2 are connected in parallel, or a combination of a serially connected configuration and a parallel connected configuration.

[0013] When the reformer 2 performs wet hydrolysis, as shown in FIG. 2, the reformer 2 can be configured, for example, with at least one steam inlet 13 for allowing steam to flow into the housing 10 and at least one purge nozzle 14 for purging gas from the housing 10. When the reformer 2 performs dry hydrolysis, as shown in FIG. 3, the reformer 2 can be configured, for example, with a jacket 15 provided on the housing 10 so as to at least partially cover the outer surface of the housing 10. The jacket 15 forms a steam flow path through which steam flows. The flow path through which steam passes can also be located inside the reactor or on the agitator shaft. In the configuration shown in FIG. 3, the jacket 15 forms a heating unit that heats the moisture contained in the waste in the housing 10 with the heat of the steam without coming into contact with the waste, thereby hydrolyzing the waste. The heating unit is not limited to a steam flow path through which steam flows, but may be a flow path through which any heating medium such as combustion exhaust gas flows, or an electric heater or the like that can indirectly heat the waste (especially the moisture in the waste) without directly contacting the waste. In either form of the reformer 2, an agitator 16 for agitating the waste within the housing 10 is provided within the housing 10. The agitator 16 is driven by a motor 17.

[0014] As shown in FIG. 1, the configuration of the microbial reaction device 3 is not particularly limited, but any configuration is acceptable as long as it uses the modified product obtained by hydrolyzing waste in the modification device 2 as a raw material and produces valuable materials by utilizing the biological action of microorganisms. For example, it may be a biogas fermenter that produces valuable biogas such as methane, a saccharification tank that produces valuable sugar from carbohydrates such as starch and cellulose, or a composting device that produces compost by composting.

[0015] <Operation of the waste treatment system according to the first embodiment of the present disclosure> Next, the operation of the waste treatment system 1 according to the first embodiment of the present disclosure will be described. As shown in Fig. 1, waste received into the housing 10 through the inlet 11 is heated by steam while being agitated by the agitator 16 (see Fig. 2 or 3). This causes a hydrolysis reaction in the waste. The conditions for this hydrolysis are not particularly limited, but can be set, for example, so that cell fluid flows out from cells contained in the food waste. Such conditions can be a temperature of from room temperature to about 250°C and a pressure of from atmospheric pressure to about 40 atmospheres.

[0016] Food waste in waste mainly contains proteins, carbohydrates, and fats. When food waste is hydrolyzed, pinholes form in the cell membranes and walls or the cell membranes and walls dissolve, causing the cell fluid to leak out. This causes the food waste to be broken down into smaller particles, and the high molecular weight components are broken down into smaller molecules. Furthermore, the amount of volatile fatty acids (VFAs) such as acetic acid increases.

[0017] The hydrophobic lignin and hemicellulose that make up the wood-like plant matter in the waste are converted into hydrophilic substances through hydrolysis and dissolved, exposing the cellulose. Paper waste in the waste becomes hydrophilic as chemicals on its surface dissolve. It is also finely crushed, softened, and reduced in size by being stirred by the mixer 16. Plastic waste in the waste is heated and softened, and then sheared and reduced in size by being stirred by the mixer 16.

[0018] The modified material, which is waste hydrolyzed in the modifying device 2, contains the components generated as described above from food waste, paper waste (including wood, etc.), and plastic waste, as well as a small amount of metal that is hardly affected by hydrolysis. Because the water content of waste with the above-described composition is relatively low, the modified material is composed mostly of solid components with only a small amount of liquid. This modified material is discharged from the housing 10 via the outlet 12 and transferred to the microbial reactor 3. When the waste has a high water content, such as sludge, the modified material also contains a large amount of liquid, resulting in a slurry-like modified material. Even in such cases, the entire amount of the modified material is transferred to the microbial reactor 3 without solid-liquid separation. In the microbial reactor 3, the modified material is subjected to the biological action of microorganisms, resulting in low molecular weight components, and valuable resources are produced.

[0019] By pulverizing food waste in the waste stream through hydrolysis, the surface area of ​​the food waste-derived components increases, increasing the area exposed to biological action by microorganisms, thereby accelerating the breakdown into smaller molecules. If the uneven distribution of food waste-derived components is suppressed and uniformed through pulverization, the activity of biological action can be uniformed and the breakdown into smaller molecules becomes stable. In addition, the increase in VFAs promotes the breakdown into smaller molecules. Furthermore, by pulverizing food waste-derived components into smaller molecules, fat foaming within the microbial reaction device 3 is suppressed. If such foaming occurs, problems such as clogging of the overflow port (not shown) of the microbial reaction device 3 can occur, but this method can suppress the occurrence of such problems.

[0020] When paper waste and plants in the waste are hydrolyzed, the cellulose is exposed, making it easier for microorganisms to access the cellulose, accelerating the breakdown into smaller molecules. In addition, when hydrolysis makes the materials hydrophilic and reduces their diameter, these components no longer float within the microbial reactor 3, reducing the risk of them hindering the breakdown into smaller molecules. When plastic waste in the waste is hydrolyzed and its diameter reduced, the risk of it hindering the breakdown into smaller molecules can also be reduced.

[0021] In this way, the modified material obtained by hydrolyzing waste in the modifying device 2 can be broken down into smaller molecules in the microbial reaction device 3 to generate valuable materials without solid-liquid separation, making it possible to generate valuable materials even from waste with a low moisture content. Furthermore, this waste treatment system 1 does not require a device for solid-liquid separation of the modified material, and only generates valuable materials with a high unit price, such as biogas, so it can treat waste at a lower cost than systems that separate the modified material into solids and liquids, generate biogas from the separated liquid, and produce fuel, fertilizer, etc. from the separated solid.

[0022] As shown in FIG. 4, in the first embodiment, when two serially connected reformers 2 (first reformer 2a and second reformer 2b) are provided, a solid-liquid separator 70 may be provided between the first reformer 2a and the second reformer 2b. The reformed product from the first reformer 2a may be subjected to solid-liquid separation, and only the separated solid may be transferred to the second reformer 2b. Solid-liquid separation allows nitrogen compounds, such as proteins that cause melanoidin production, to be separated into the liquid, thereby suppressing the production of melanoidin during hydrolysis in the second reformer. If melanoidin flows into a methane fermentation tank serving as a microbial reactor 3, it inhibits methane fermentation. Therefore, by performing solid-liquid separation of the reformed product from the first reformer and transferring only the separated solid to the second reformer, the risk of inhibiting methane fermentation in the methane fermentation tank can be reduced. Since the separated liquid contains nitrogen compounds, this liquid may be supplied to the methane fermentation tank by bypassing the second reformer 2b. This allows nitrogen components to be replenished in the methane fermentation tank.

[0023] In the first embodiment, the steam used to heat the waste in the reformer 2 may be supplied to the microbial reaction device 3 and used as a heat source for keeping the temperature during the microbial reaction in the microbial reaction device 3. This reduces the operating cost compared to when a heat source required for operating the microbial reaction device 3 is separately prepared.

[0024] (Embodiment 2) Next, a waste treatment system according to embodiment 2 will be described. The waste treatment system according to embodiment 2 is different from embodiment 1 in that it adds a separation device that separates unsuitable reactants that do not contribute to the degradation of molecules by microorganisms, i.e., that are unsuitable for degradation, from modified materials in the microbial reaction device 3. In embodiment 2, the same components as those in embodiment 1 are given the same reference numerals, and detailed descriptions thereof will be omitted.

[0025] <Configuration of waste treatment system according to embodiment 2 of the present disclosure> As shown in Figure 5, a waste treatment system 1 according to a second embodiment of the present disclosure includes a separator 4 disposed between a reformer 2 and a microbial reactor 3. The separator 4 separates the reformed material into large particle size components and small particle size components smaller than the large particle size components, and is, for example, a screen with a given mesh size, the mesh size corresponding to the particle size at the boundary between the large particle size components and the small particle size components. The other configurations are the same as those of the first embodiment.

[0026] <Operation of the waste treatment system according to the second embodiment of the present disclosure> In the waste treatment system 1 according to the second embodiment of the present disclosure, the reformed material is separated into large particle size components and small particle size components in the separator 4, and only the small particle size components are supplied to the microbial reactor 3, where only the small particle size components are degraded to produce valuable materials. The main components of the large particle size components are those that have relatively large particle sizes even after hydrolysis in the reformer 2, and cannot be degraded to small molecules in the microbial reactor 3, such as those derived from plastic waste or metals. In other words, the large particle size components and the small particle size components are unsuitable and suitable for microbial reaction, respectively.

[0027] In the second embodiment, such large particle size components are separated from the modified product by the separator 4, and only small particle size components are supplied to the microbial reaction device 3, thereby reducing the amount of unsuitable reaction materials supplied to the microbial reaction device 3. As a result, the risk of inhibiting the depolymerization in the microbial reaction device 3 is reduced, and the depolymerization can be carried out efficiently.

[0028] Regarding a screen as an example of the separator 4, waste with a total solids concentration (TS) of 53% was hydrolyzed (heated to a predetermined temperature between room temperature and 240°C while stirring in a sealed container and held for a certain period of time), and the resulting modified product was then passed through a mesh screen. As a result, the recovery rate of small-particle compatible materials (organic matter such as paper and kitchen waste) was 40 wt% when the waste was crushed and separated using a screen as in the conventional method. By using the method of the present invention, a recovery rate of 80 wt% was achieved, and the proportion of unsuitable materials (e.g., plastic waste) mixed into the suitable materials was reduced to less than 10 wt%. Thus, it was found that the use of a screen can remove unsuitable materials from the hydrolyzed modified product to a certain extent. Therefore, it can be inferred that installing the separator 4 between the reformer 2 and the microbial reactor 3 reduces the risk of impeding the depolymerization in the microbial reactor 3 and enables efficient depolymerization. While this example illustrates separation based on particle size, other separation methods, such as gravity separation, winnowing, and wet separation, can also be used. Therefore, the separator 4 can be a device using gravity separation, winnowing, wet separation, or a combination of these. If the microbial reactor 3 is a methane fermentation tank, it needs to be replenished with water, so wet separation is suitable. If the microbial reactor 3 is a composting device, it needs to have a low moisture content, so winnowing or separation by screen is suitable. An air jet spray or the like can be used to improve the recovery rate of small particle size components.

[0029] In the second embodiment, when treating a material such as sludge with a relatively high water content, the TS of the reformed product flowing out of the reforming apparatus 2 is low, which may prevent successful separation of unsuitable materials in the separator 4. In such a case, after hydrolysis in the reforming apparatus 2, the purge nozzle 14 (see FIG. 2) can be opened for a certain period of time to perform an operation similar to vacuum drying, thereby reducing the water content of the reformed product and adjusting the TS of the reformed product. In this case, the purge nozzle 14 serves as a moisture adjuster for adjusting the water content of the reformed product. In this embodiment, as shown in FIG. 6, a drying device 71 of any configuration may be provided in the reformed product transfer line 5 connecting the reforming apparatus 2 and the separator 4 as a moisture adjuster capable of adjusting the water content of the reformed product. In this case, a dehydrator may be provided as the moisture adjuster. Conversely, the moisture adjuster may adjust the TS of the hydrolyzed reformed product by adding water to the hydrolyzed reformed product to increase its water content and improve its fluidity. In this case, a water spray may be provided as the moisture adjuster. Furthermore, if the moisture adjustment device is configured to add moisture to the small particle size components separated in the separation device 4 and remove excess moisture, this moisture adjustment device can also function as a washing device to wash the reaction-compatible material adhering to the reaction-compatible material. This allows the reaction-compatible material to be supplied to the microbial reactor 3 after reducing the content of fermentation inhibitors such as melanoidins in the reaction-compatible material, thereby reducing the risk of reaction inhibition in the microbial reactor 3. Furthermore, if the moisture adjustment device is used as a washing device to wash the reaction-unsuitable material, which is the large particle size component separated in the separation device 4, the small particle size components adhering to the reaction-unsuitable material can be recovered as reaction-compatible material, thereby improving the recovery rate of the reaction-compatible material. The moisture adjustment device can also be installed inside the separation device 4. The modified product transfer line 5 may be a pipe if the modified product is in a slurry state, or a conveyor or the like if the modified product is solid. Even if the modified product is solid, the modified product transfer line 5 may be a pipe if it can be pumped by air or the like.

[0030] (Embodiment 3) Next, a waste treatment system according to embodiment 3 will be described. The waste treatment system according to embodiment 3 is different from embodiment 2 in that it is configured to estimate the content of unsuitable substances for reaction in the modified product. In embodiment 3, the same components as those in embodiment 2 are given the same reference numerals, and detailed descriptions thereof will be omitted.

[0031] <Configuration of waste treatment system according to embodiment 3 of the present disclosure> As shown in Figure 7, in the third embodiment, near-infrared sensors 61, 62 such as hyperspectral cameras are provided on the modified material transfer line 5 and the modified material transfer line 7 that connects the separation device 4 and the microbial reaction device 3. The near-infrared sensors 61, 62 are each electrically connected to the control device 36. The specific configuration of the modified material transfer line 7 is the same as that of the modified material transfer line 5. The other configurations are the same as those in the second embodiment.

[0032] <Operation of the waste treatment system according to the third embodiment of the present disclosure> The operation of embodiment 3 is basically the same as embodiment 2. In embodiment 3, near-infrared sensors 61 and 62 acquire spectral data of the modified material while the modified material is being transported from the reformer 2 to the microbial reaction device 3, and the acquired spectral data is transmitted to the control device 36, which then performs an operation of estimating the content of unsuitable substances for reaction in the modified material based on the spectral data. The following describes the operations that differ from embodiment 2.

[0033] An example of the spectral data acquired by the near-infrared sensors 61, 62 is shown in Fig. 8. The control device 36 stores in advance, as a database, spectral data of modified products with different contents of unsuitable reaction substances, as shown as a, b, and c (not limited to three, but may be four or more) in Fig. 9. The control device 36 identifies the acquired spectral data (Fig. 8) by combining multiple spectral data stored in the database using a means such as the weighted average method or the kernel method, and can estimate the concentration of the unsuitable reaction substance based on the weighted value.

[0034] As another example, as shown in Fig. 10, spectral data of several modified products with different concentrations of the unsuitable reaction substance (10%, 50%, and 100% are shown in Fig. 10, but these are merely examples) are acquired, and the change in intensity between two different specific wavelengths (e.g., 1500 nm and 1700 nm) in each spectral data is read, and a relationship (calibration curve) between the concentration of the unsuitable reaction substance and the change in intensity between the two different specific wavelengths is created in advance and stored in the control device 36, as shown in Fig. 11. The control device 36 reads the absorbance at a specific wavelength of the spectral data acquired by the near-infrared sensors 61 and 62, and can estimate the concentration of the unsuitable reaction substance in the modified product based on this calibration curve.

[0035] As yet another example, a piezoelectric sensor or the like is provided in addition to the near-infrared sensors 61 and 62 to measure the weight of the modified product during transportation. The type of unsuitable reaction substance can also be estimated from the spectrum data acquired using the near-infrared sensors 61 and 62, so the weight ratio of unsuitable reaction substances to suitable reaction substances in the modified product being transported can also be estimated from the type of unsuitable reaction substance and the weight of the modified product.

[0036] Based on the content of unsuitable reaction substances in the reformed product estimated in this way, abnormalities in the reformer 2 and the separator 4, and abnormalities in the waste material fed into the reformer 2 can be detected.

[0037] In the third embodiment, the near-infrared sensors 61 and 62 are used to estimate the content of unsuitable reaction substances in the reformed product, but this is not limiting. The near-infrared sensors can also be used to predict the properties of waste fed into the reformer 2. For example, the near-infrared sensors acquire spectral data of the waste, and the proportions of moisture, protein, carbohydrates, fat, plastic components, etc. can be determined from the acquired spectral data. Based on the properties of the waste thus obtained, the hydrolysis conditions (temperature, pressure, time, agitation speed, etc.) in the reformer 2 can be set. Furthermore, the separation conditions (mesh size, moisture content, vibration frequency, etc.) for the separator 4 can also be set. Note that a digital camera may be used instead of the near-infrared sensors 61 and 62, and the properties of the waste may be predicted based on images taken by the digital camera.

[0038] If the properties of the waste are known in advance because the waste receiving route is clear, for example, the hydrolysis conditions in the reformer 2 and the separation conditions in the separator 4 can be set based on those properties. Alternatively, the properties of the waste can be estimated using AI predictions that use information on the properties of the waste, such as waste collection dates, event calendars (information on the type of waste), past waste analysis results, or local purchasing information. That is, the control device 36 may function as a detection device and detect information on the properties of the waste as an indicator of the hydrolysis status of the waste in the reformer 2, and then the control device 36 may estimate the hydrolysis status based on this indicator.

[0039] (Embodiment 4) Next, a waste treatment system according to embodiment 4 will be described. The waste treatment system according to embodiment 4 is different from any of embodiments 1 to 3 in that the hydrolysis conditions are adjusted based on the hydrolysis status of the waste in the reformer 2. Hereinafter, embodiment 4 will be described as a configuration in which the hydrolysis conditions are adjusted compared to embodiment 2, but embodiment 4 may also be configured by adjusting the hydrolysis conditions compared to embodiment 1 or 3. In embodiment 4, the same components as those in embodiment 2 are designated by the same reference numerals, and detailed description thereof will be omitted.

[0040] <Configuration of waste treatment system according to embodiment 4 of the present disclosure> In the fourth embodiment, the microbial reaction device 3 will be described as a biogas fermenter 3a that produces biogas such as methane. As shown in Fig. 12, the waste treatment system 1 according to the fourth embodiment of the present disclosure includes a gas holder 31 that stores the biogas produced in the biogas fermenter 3a, a combustion boiler 32 that generates steam using the biogas stored in the gas holder 31 as fuel, a gas engine 33 that is driven by the biogas stored in the gas holder 31 as fuel, an exhaust gas boiler 34 that generates steam using the heat of the exhaust gas from the gas engine 33, and a dehydrator 35 that dehydrates the fermentation residue in the biogas fermenter 3a. Although not an essential component, a water injection pipe 37 that connects the dehydrator 35 to the reformate transfer line 5 may be provided.

[0041] The combustion boiler 32 and the exhaust gas boiler 34 are each connected to the steam inlet 13 (see FIG. 2) or jacket 15 (see FIG. 3) of the reformer 2 via a steam supply pipe 38, so that steam generated in the combustion boiler 32 and the exhaust gas boiler 34 is supplied to the reformer 2. The steam supply pipe 38 is provided with steam supply amount adjustment valves 39a, 39b for adjusting the amount of steam supplied from the combustion boiler 32 and the exhaust gas boiler 34 to the reformer 2. The waste treatment system 1 is equipped with a combustion boiler control device 32a that controls the temperature and amount of steam generated in the combustion boiler 32, and an exhaust gas boiler control device 34a that controls the temperature and amount of steam generated in the exhaust gas boiler 34. The waste treatment system 1 further includes a control device 36, which is electrically connected to the motor 17 that drives the agitator 16 of the reformer 2, the combustion boiler control device 32a, the exhaust gas boiler control device 34a, and the steam supply amount adjustment valves 39a, 39b. Although not shown in Fig. 12, the control device 36 is configured to be able to acquire the hydrolysis status (temperature, pressure, etc.) in the reformer 2.

[0042] The combustion boiler control device 32a and the exhaust gas boiler control device 34a control the temperature and amount of steam generated in the combustion boiler 32 and the exhaust gas boiler 34, respectively, and the steam supply amount adjustment valves 39a and 39b adjust the amount of steam supplied to the reformer 2. These devices adjust the conditions (temperature and pressure) for hydrolysis of the waste in the reformer 2, and therefore constitute an adjustment device for adjusting the conditions for hydrolysis of the waste in the reformer 2. The other configurations are the same as those of the second embodiment.

[0043] <Operation of the waste treatment system according to the fourth embodiment of the present disclosure> The operations from hydrolyzing the waste in the reformer 2 to generating biogas as a valuable resource in the microbial reaction device 3, i.e., the biogas fermenter 3a, are the same as those in the second embodiment. The biogas generated in the biogas fermenter 3a is stored in the gas holder 31. Depending on the operating conditions of the combustion boiler 32 and the gas engine 33, the biogas is supplied from the gas holder 31 to each of the combustion boiler 32 and the gas engine 33. The combustion boiler 32 generates steam using the biogas as fuel. The exhaust gas boiler 34 generates steam using the heat of the exhaust gas from the gas engine. The steam generated in the combustion boiler 32 and the exhaust gas boiler 34 is supplied to the reformer 2 and used for hydrolysis of the waste.

[0044] Although the operation methods of the combustion boiler 32 and the exhaust gas boiler 34 are not particularly limited, an example of an operation method will be described below. The exhaust gas boiler 34 is always operated while the waste is being hydrolyzed in the reformer 2. The combustion boiler 32 is not operated while the hydrolysis conditions in the reformer 2 can be adjusted using only the steam generated in the exhaust gas boiler 34. When adjusting the hydrolysis conditions in accordance with the amount of waste input to the reformer 2 and the composition of the waste components, if the steam generated in the exhaust gas boiler 34 alone is insufficient, the combustion boiler 32 is operated to supply not only the steam generated in the exhaust gas boiler 34 but also the steam generated in the combustion boiler 32 to the reformer 2. In this way, the adjustment range of the hydrolysis conditions in the reformer 2 can be wider than when only the exhaust gas boiler 34 is provided. Note that by providing two or more gas engines 33 and operating the number of gas engines 33 according to the amount of steam generated in the exhaust gas boiler 34, the adjustment range of the hydrolysis conditions in the reformer 2 can be further widened.

[0045] In order to adjust the hydrolysis conditions in the reformer 2, it is necessary to detect the hydrolysis status in the reformer 2. There are no particular limitations on the method for detecting the hydrolysis status, but one example of such a method will be described below. The control device 36 detects the torque of the motor 17 as an indicator of the hydrolysis status of the waste in the reformer 2. Hydrolysis begins after the waste is fed into the reformer 2, and the torque of the motor 17 fluctuates according to the progress of the hydrolysis. It is possible to detect the hydrolysis status from fluctuations in the torque of the motor 17. In addition, it is possible to detect the hydrolysis status from an indicator that takes into account various measurement values ​​such as the hydrolysis temperature, pressure, time, and amount of steam supplied.

[0046] The change in the torque of the motor 17 over time may vary depending on the composition of the waste, etc. However, if there is no significant difference in the composition of the waste hydrolyzed each time in the reformer 2, it is possible to detect such a change in the torque of the motor 17 over time in advance and compare it with the previously detected change over time to estimate the hydrolysis status in the reformer 2. For this reason, the control device 36 that detects the torque of the motor 17 constitutes a detection device that detects an indicator of the hydrolysis status of the waste in the reformer 2. Note that a detection device for detecting the torque of the motor 17 may be provided separately from the control device 36, and the control device 36 may be configured to receive a signal related to the torque of the motor 17 from this detection device.

[0047] The detection result of the hydrolysis status based on the torque of the motor 17 may indicate, for example, that the waste has not been atomized sufficiently, or that the waste has been atomized so much that the plastic waste has been atomized to particle sizes that would normally be impossible to achieve. In the former case, for example, it may be necessary to increase the temperature of hydrolysis, so it may be possible to increase the amount of steam supplied to the reformer 2. In the latter case, for example, it may be acceptable to lower the temperature of hydrolysis from the viewpoint of the operating costs of the waste treatment system 1, so it may be possible to decrease the amount of steam supplied to the reformer 2.

[0048] In this way, the control device 36 estimates the hydrolysis status in the reformer 2 based on the torque of the motor 17, and controls at least one of the adjusting devices, i.e., the combustion boiler control device 32a, the exhaust gas boiler control device 34a, and the steam supply amount adjusting valves 39a, 39b, based on the estimated hydrolysis status to adjust the temperature (pressure) and supply amount of steam supplied to the reformer 2. As a result, the hydrolysis status in the reformer 2 changes. In this way, the control device 36 adjusts the hydrolysis conditions in the reformer 2 based on the hydrolysis status in the reformer 2. Furthermore, since the hydrolysis status can also indicate whether hydrolysis is complete or not, it becomes possible to adjust the hydrolysis time.

[0049] In this way, in the fourth embodiment, the modified material in a condition suitable for the microbial reaction can be supplied to the biogas fermenter 3a, so that biogas can be efficiently produced by the microbial reaction.

[0050] In the second embodiment, it was explained that the TS of the hydrolyzed modified product may be adjusted by adding water to the modified product to increase its water content in order to increase its fluidity. In the fourth embodiment, to adjust the TS of the modified product in this manner, water dehydrated from the fermentation residue in the biogas fermenter 3a in the dehydration device 35 or boiler blow water may be supplied to the modified product in the modified product transfer line 5 via the water injection pipe 37. Therefore, the water injection pipe 37 constitutes a moisture adjustment device. Because the dehydrated water and boiler blow water contain ammonia, nitrogen-containing substances can also be replenished to the modified product when the nitrogen content of the waste is low. From the perspective of replenishment of nitrogen-containing substances, the dehydrated water and boiler blow water are not limited to being supplied to the modified product in the modified product transfer line 5, but may also be supplied to the biogas fermenter 3a or the reformer 2. In this case, the water injection pipe 37 may be connected to the biogas fermenter 3a or the reformer 2. In addition, in the third embodiment, the control device 36 estimates the hydrolysis conditions based on the torque of the motor 17, but the hydrolysis conditions may be estimated based on the current value of the motor 17. That is, the current value of the motor 17 may be used as an index of the hydrolysis status of the waste in the reforming device 2.

[0051] <Modification of the waste treatment system according to the fourth embodiment of the present disclosure> In the fourth embodiment, the hydrolysis conditions in the reformer 2 are adjusted based on the hydrolysis status in the reformer 2, but the present invention is not limited to this. For example, as shown in FIG. 13, the separator 4 may be two separators 4a and 4b with different mesh sizes arranged in parallel with the flow of the reformate. In this case, the mesh size of the separator 4a is smaller than that of the separator 4b. The reformate transfer line 5 is provided with a switching device 6 for supplying the reformate to either the separator 4a or 4b. The motor 17 and the switching device 6 are electrically connected to the control device 36.

[0052] If the torque of motor 17 does not fluctuate periodically even after hydrolysis has begun, but instead fluctuates irregularly, indicating that the waste is not being broken down into smaller particles, control device 36 operates switching device 6 to supply the reformed material to separator 4b. If the waste is not being broken down into smaller particles, the size of unsuitable materials for reaction, especially plastic waste, will remain large. Therefore, separator 4b with a larger mesh size is selected to remove the unsuitable materials for reaction while still allowing the supply of large suitable materials to biogas fermenter 3a. On the other hand, if the cyclical increase and decrease is small and the waste is being broken down into smaller particles, control device 36 operates switching device 6 to supply the reformed material to separator 4a. This makes it possible to remove unsuitable materials that have become too fine.

[0053] 13, two separators 4a and 4b with different mesh sizes are provided, but the number is not limited to two, and three or more separators with different mesh sizes may be provided. This allows the selection of three or more separators with different mesh sizes depending on the hydrolysis conditions in the reformer 2.

[0054] (Embodiment 5) Next, a waste treatment system according to embodiment 5 will be described. The waste treatment system according to embodiment 5 is a modification of any of embodiments 1 to 4, in that the hydrolysis status of the waste in the reformer 2 is estimated based on the reaction conditions in the microbial reaction device 3, and the hydrolysis conditions for the next batch of waste in the reformer 2 are adjusted based on the hydrolysis status. The following description will be given of a configuration in which the above-mentioned modifications are made to embodiment 4, but embodiment 5 may also be configured by making the above-mentioned modifications to any of embodiments 1 to 3. In embodiment 5, the same components as those in embodiment 4 are given the same reference numerals, and detailed description thereof will be omitted.

[0055] <Configuration of waste treatment system according to embodiment 5 of the present disclosure> 14, a waste treatment system 1 according to a fifth embodiment of the present disclosure is provided with at least one of a volatile fatty acid sensor (VFA sensor) 41 that detects the VFA concentration in the reformate transported through the reformate transport line 5, or a VFA sensor 42 that detects the VFA concentration in the biogas fermenter 3a. A control device 36 receives the detection value of at least one of the VFA sensors 41 or 42. The other configurations are the same as those of the fourth embodiment.

[0056] <Operation of the waste treatment system according to the fifth embodiment of the present disclosure> The operation of embodiment 5 is basically the same as that of embodiment 4. However, the difference is that the reaction conditions in the biogas fermenter 3a are detected based on the detection values ​​of the VFA sensors 41, 42 as indicators of the hydrolysis status of the waste in the reformer 2, the hydrolysis status in the reformer 2 is estimated from the reaction conditions, and the hydrolysis conditions for the next batch of waste in the reformer 2 are adjusted based on the estimated hydrolysis status. Therefore, the VFA sensors 41, 42 constitute a detection device that detects an indicator of the hydrolysis status of the waste in the reformer 2. The operation of estimating the hydrolysis status of the waste in the reformer 2 will be described below. Note that the following description assumes that both VFA sensors 41 and 42 are provided.

[0057] During operation of the waste treatment system 1, the VFA sensor 41 detects the VFA concentration in the reformed product flowing out from the reformer 2. The VFA sensor 42 detects the VFA concentration in the content of the biogas fermenter 3a. The configuration of the VFA sensors 41 and 42 is not particularly limited, and any known sensor can be used to detect the VFA concentration. However, as an example, the configuration of a sensor that can be used as the VFA sensor 42 will be described. The biogas fermenter 3a is equipped with a content circulation line that extracts a portion of the content and returns it to the biogas fermenter 3a, an extraction line that extracts a portion of the content from the circulation line, and a dilution water supply line that supplies dilution water to the extraction line. A probe is provided for measuring the content diluted with dilution water, and the VFA concentration in the content of the biogas fermenter 3a is detected by irradiating infrared light from the probe onto the content diluted with dilution water and receiving the transmitted light. The VFA sensor 41, which detects the VFA concentration in the reformed product flowing out from the reformer 2, can detect the VFA concentration using infrared light.

[0058] Signals related to the VFA concentrations detected by the VFA sensors 41, 42 are transmitted from the VFA sensors 41, 42 to the control device 36. Upper and lower limit values ​​for the VFA concentration are preset in the control device 36, and the control device 36 determines whether the transmitted VFA concentration is between the upper and lower limit values. If the VFA concentration is below the lower limit value, the methane fermentation reaction slows down, and the VFA concentration must be increased. Specifically, for example, the temperature or amount of steam supplied to the reformer 2 for hydrolysis of the next batch of waste may be increased, the hydrolysis time may be extended, or the amount of methane fermentation raw material supplied per cycle or the number of times it is supplied may be increased, thereby increasing the total amount of VFAs input to the biogas fermenter 3a. Conversely, if the VFA concentration is too high, VFAs will accumulate in the biogas fermenter 3a, causing rancidity. Therefore, if the detected VFA concentration exceeds the upper limit, the temperature or amount of steam supplied to the reformer 2 for hydrolysis of the next batch of waste may be reduced, the hydrolysis time may be shortened, or the amount or number of times the methane fermentation raw material is supplied may be adjusted.

[0059] In this way, the hydrolysis status of the waste in the reformer 2 is estimated based on the VFA concentration in the reformed product obtained by hydrolyzing the waste and the VFA concentration in the contents of the biogas fermenter 3a, and the hydrolysis conditions for the next batch of waste in the reformer 2 are adjusted based on this hydrolysis status.This makes it possible to maintain the VFA concentration in the contents of the next batch of biogas fermenter 3a at a condition suitable for methane fermentation, thereby enabling efficient production of biogas through microbial reaction.

[0060] In the fifth embodiment, the VFA sensors 41 and 42 are permanently installed, but it is also possible to sample the modified material and the contents of the biogas fermenter 3a, analyze the VFA concentration contained therein, and calculate the hydrolysis status from the data of the analysis results.

[0061] (Embodiment 6) Next, a waste treatment system according to embodiment 6 will be described. The waste treatment system according to embodiment 6 is a system in which the operation of detecting reaction conditions in the microbial reaction device 3 is changed from that of embodiments 1 to 5. In the following, a configuration in which the operation of detecting reaction conditions in the microbial reaction device 3 is changed from that of embodiment 5 will be described, but embodiment 6 may also be configured by changing the operation of detecting reaction conditions in the microbial reaction device 3 from any of embodiments 1 to 4. In embodiment 6, the same components as those of embodiment 5 are given the same reference numerals, and detailed description thereof will be omitted.

[0062] <Configuration of waste treatment system according to embodiment 6 of the present disclosure> As shown in Figure 15, the waste treatment system 1 according to the sixth embodiment of the present disclosure is provided with a fermentation inhibitor sensor 51 that detects the concentrations of fermentation inhibitors such as melanoidin, furoral, and phenol in the biogas fermenter 3a as an indicator of the state of hydrolysis of the waste in the reformer 2. The control device 36 receives the detected value of the fermentation inhibitor sensor 51. The other configurations are the same as those of the fifth embodiment except that the VFA sensors 41, 42 (see Figure 14) are not provided.

[0063] <Operation of the waste treatment system according to the sixth embodiment of the present disclosure> The operation of the sixth embodiment is basically the same as that of the fifth embodiment, except for the operation of detecting the reaction conditions in the biogas fermenter 3a. The operation of detecting the reaction conditions in the biogas fermenter 3a will be described below.

[0064] During operation of the waste treatment system 1, the fermentation inhibitor sensor 51 detects the concentration of a fermentation inhibitor in the contents of the biogas fermenter 3a. The configuration of the fermentation inhibitor sensor 51 is not particularly limited, and any known sensor can be used to detect the concentration of a fermentation inhibitor. As an example, however, the configuration of a sensor that can be used as the fermentation inhibitor sensor 51 will be described. The biogas fermenter 3a is provided with a contents circulation line that extracts a portion of the contents and returns it to the biogas fermenter 3a, an extraction line that extracts a portion of the contents from the circulation line, and a dilution water supply line that supplies dilution water to the extraction line. A probe is provided for measuring the contents diluted with dilution water, and the probe irradiates ultraviolet light onto the contents diluted with dilution water and receives the transmitted light, thereby detecting the concentration of a fermentation inhibitor in the contents of the biogas fermenter 3a.

[0065] A signal indicating the concentration of the fermentation inhibitor detected by the fermentation inhibitor sensor 51 is transmitted from the fermentation inhibitor sensor 51 to the control device 36. An upper limit for the concentration of the fermentation inhibitor is preset in the control device 36, and the control device 36 determines whether the transmitted concentration of the fermentation inhibitor is equal to or lower than the upper limit. If the concentration of the fermentation inhibitor exceeds the upper limit, methane fermentation is inhibited and the reaction slows down, so the concentration of the fermentation inhibitor must be reduced. Specifically, the temperature and amount of steam supplied to the reformer 2 for hydrolysis of the next batch of waste are reduced.

[0066] In embodiment 6, the hydrolysis status of the waste in the reforming device 2 is estimated based on the concentration of the fermentation inhibitor detected by the fermentation inhibitor sensor 51, and therefore the fermentation inhibitor sensor 51 constitutes a detection device that detects the hydrolysis status of the waste in the reforming device 2.

[0067] In this way, the hydrolysis status of the waste in the reforming device 2 is estimated based on the concentration of fermentation inhibitors in the contents of the biogas fermenter 3a, and the hydrolysis conditions for the next batch of waste in the reforming device 2 are adjusted based on this hydrolysis status. This reduces the concentration of fermentation inhibitors in the contents of the next batch of biogas fermenter 3a, thereby enabling efficient production of biogas through microbial reaction.

[0068] <Modification of the waste treatment system according to the sixth embodiment of the present disclosure> In the sixth embodiment, the hydrolysis conditions for the next batch in the reformer 2 are adjusted based on the concentration of the fermentation inhibitor in the content of the biogas fermenter 3a, but the present invention is not limited to this. For example, if the composition of the waste to be hydrolyzed in the reformer 2 varies significantly for each batch, it may be difficult to adjust the hydrolysis conditions for the next batch to appropriate reaction conditions even if they are adjusted based on the reaction conditions in the biogas fermenter 3a for the previous batch.

[0069] 16, a fermentation inhibitor sensor 51 may be provided on the reformed material transfer line 5 so as to detect the concentration of fermentation inhibitors in the reformed material flowing out from the reformer 2, and a detour line 8 may be provided that branches off from the reformed material transfer line 7 that connects the separator 4 and the biogas fermenter 3a and rejoins the reformed material transfer line 7 downstream of the branching point, with at least one avoidance tank 52 provided on the detour line 8. A switching device 9 may be provided at the upstream end of the detour line 8 to supply the reformed material flowing out from the separator 4 to either the avoidance tank 52 or the biogas fermenter 3a.

[0070] In this modification, when the detection value by the fermentation inhibitor sensor 51 exceeds the upper limit, the control device 36 switches the switching device 9 so that the reformed material is not supplied to the biogas fermenter 3a but is instead stored in the avoidance tank 52. When the concentration of fermentation inhibitors in the reformed material from the next batch of hydrolysis falls below the upper limit, the reformed material is gradually mixed with the reformed material with a higher concentration of fermentation inhibitors stored in the avoidance tank 52 and supplied to the biogas fermenter 3a. In this way, the concentration of fermentation inhibitors in the content of the biogas fermenter 3a can be kept below the upper limit, allowing for efficient biogas production by microbial reaction.

[0071] In the sixth embodiment, the fermentation inhibitor sensor 51 is permanently installed, but it is also possible to sample the modified material and the contents of the biogas fermenter 3a, analyze the concentration of the fermentation inhibitors contained therein, and calculate the hydrolysis status from the data of the analysis results.

[0072] In embodiment 6, the control device 36 may learn the correspondence between the properties of the waste, the hydrolysis conditions, and the water decomposition status, and adjust the hydrolysis conditions based on a trained model constructed as a result of the learning.

[0073] In the fifth and sixth embodiments, the VFA sensors 41, 42 and the fermentation inhibitor sensor 51 have been described as examples of detection devices, but the present invention is not limited to these. Sensors that detect the amount of gas generated in the microbial reaction device 3, the VFA concentration in the gas, the pH, electrical conductivity, alkalinity, ammonia concentration, bacterial cell concentration, etc. of the contents in the microbial reaction device 3 may also be used. Sensors that detect the pH, electrical conductivity, color, inhibitor concentration, VFA concentration, ammonia concentration, particle size distribution, etc. during hydrolysis may also be used. The hydrolysis status of the waste in the reformer 2 can be estimated by calculating an index using a function that uses these detected values.

[0074] In the first to sixth embodiments, the reformer 2 hydrolyzes the waste in a batchwise manner, but it may also hydrolyze the waste in a flow-through manner. However, in a reformer using flow-through hydrolysis, a method of making the waste fluid to supply the waste to the reformer, for example, by reducing the size of the waste and supplying it as a slurry in a large amount of water, is conceivable. In this case, extra energy is required, such as energy to reduce the size of the waste and energy to heat the water in the slurry during hydrolysis. In contrast, in a reformer using batch-wise hydrolysis, there is no need to reduce the size of the waste, and the waste can be supplied to the reformer in its original state, thereby eliminating the extra energy required in a reformer using flow-through hydrolysis.

[0075] The contents described in each of the above embodiments can be understood, for example, as follows.

[0076] [1] A waste treatment system according to one aspect includes: at least one reformer (2) for hydrolyzing the waste material; a microbial reaction device (3) for converting the modified waste, which contains at least solids and which has been hydrolyzed in the at least one reforming device (2), into lower molecular weight substances using microorganisms; Equipped with.

[0077] According to the waste treatment system of the present disclosure, waste hydrolyzed in a reforming device can be broken down into smaller molecules in a microbial reactor to produce valuable materials without solid-liquid separation, so even waste with a low moisture content (preferably 70% or less) can be treated at low cost.

[0078] [2] A waste treatment system according to another aspect is the waste treatment system according to [1], The at least one reformer (2) a housing (10) for receiving the waste; an inlet (11) for inserting the waste into the housing (10); an outlet (12) for discharging the reformed product from the housing (10); on-off valves (18, 19) for opening and closing the inlet (11) and the outlet (12), respectively; Equipped with The on-off valves (18, 19) are closed to seal the housing (10), and the waste within the housing (10) is hydrolyzed in a batchwise manner.

[0079] In a reformer that uses flow-through hydrolysis, the waste must be made fluid in order to be supplied to the reformer. For example, the waste must be reduced in size and supplied as a slurry in a large amount of water. In this case, extra energy is required, such as the energy required to reduce the size of the waste and the energy required to heat the water in the slurry during hydrolysis. In contrast, with the configuration [2] above, since hydrolysis is performed batchwise, there is no need to reduce the size of the waste and it can be supplied to the reformer in its original state, eliminating the extra energy required in a reformer that uses flow-through hydrolysis.

[0080] [3] A waste treatment system according to another embodiment is the waste treatment system according to [1] or [2], The at least one reformer (2) comprises a housing (10) for receiving the waste; The at least one reformer (2) is configured to supply steam into the housing (10) and to use the steam to heat and hydrolyze the waste material in the housing (10).

[0081] According to this configuration, the hydrolysis conditions can be easily adjusted by adjusting the temperature, pressure, supply amount, etc. of the steam.

[0082] [4] A waste treatment system according to another embodiment is the waste treatment system according to [1] or [2], The at least one reformer (2) comprises a housing (10) for receiving the waste; The housing (10) is provided with a heating section (jacket 15) that heats the moisture contained in the waste within the housing (10) without contacting the waste, thereby hydrolyzing the waste.

[0083] According to this configuration, the hydrolysis conditions can be easily adjusted by adjusting the temperature, pressure, supply amount, etc. of the steam.

[0084] [5] A waste treatment system according to another embodiment is the waste treatment system according to [1] to [4], In said at least one reformer (2), hydrolysis is carried out at a temperature between ambient temperature and 250° C. and at a pressure between atmospheric pressure and 40 atmospheres.

[0085] This configuration allows the cells contained in the food waste to release cell fluid, which breaks down the food waste into smaller particles and reduces the molecular weight of the high molecular weight components. Furthermore, volatile fatty acids (VFAs) such as acetic acid are increased.

[0086] [6] A waste treatment system according to another embodiment is the waste treatment system according to any one of [1] to [5], the at least one reformer (2) including a first reformer (2a) and a second reformer (2b); a solid-liquid separator (70) for separating the waste material hydrolyzed in the first reforming device (2a) into solid and liquid; Equipped with In the second reformer (2b), only the solid separated in the solid-liquid separator (70) is hydrolyzed.

[0087] With this configuration, nitrogen compounds such as proteins that cause melanoidin production can be separated into the liquid side by solid-liquid separation, thereby suppressing the production of melanoidin during hydrolysis in the second reforming device. If melanoidin flows into a methane fermentation tank serving as a microbial reactor, it will inhibit methane fermentation. Therefore, by performing solid-liquid separation of the reformed product in the first reforming device and transferring only the separated solid to the second reforming device, the risk of inhibiting methane fermentation in the methane fermentation tank can be reduced.

[0088] [7] A waste treatment system according to another embodiment is the waste treatment system according to any one of [1] to [6], The microbial reaction device (3) a biogas fermenter (3a) for producing biogas; a saccharification tank for producing sugar from carbohydrates; A composting device that produces compost; It includes at least one of the following:

[0089] According to this configuration, one or more desired valuable materials can be produced.

[0090] [8] A waste treatment system according to another embodiment is the waste treatment system according to any one of [1] to [7], A separation device (4) is further provided between the at least one reforming device (2) and the microbial reaction device (3) for separating unsuitable reaction materials that are unsuitable for degradation to lower molecules by the microorganisms in the microbial reaction device (3) from the reformed material.

[0091] With this configuration, the unsuitable reaction materials are separated from the reformate in the separator, thereby reducing the amount of unsuitable reaction materials supplied to the microbial reactor, thereby reducing the risk of inhibiting the microbial reaction in the microbial reactor and enabling the efficient production of valuable materials through the microbial reaction.

[0092] [9] A waste treatment system according to another aspect is the waste treatment system according to [8], A moisture adjusting device is provided to adjust the moisture content of the modified product.

[0093] According to this configuration, the TS of the reformate flowing out from the reforming device can be adjusted, so that the separation device can effectively separate out unsuitable reactants.

[0094]

[10] A waste treatment system according to another aspect is the waste treatment system according to [9], The moisture adjusting device is a drying device (71) that reduces the moisture content of the modified product.

[0095] With this configuration, when treating a material such as sludge with a relatively high water content, the TS of the reformed product flowing out of the reforming device will be low, which may prevent the separation of unsuitable reactants in the separator. In contrast, with the configuration of

[10] above, the moisture content of the reformed product can be reduced by the dryer, and the TS of the reformed product can be adjusted, allowing the separation of unsuitable reactants in the separator to be performed effectively.

[0096]

[11] A waste treatment system according to another aspect is the waste treatment system according to [9], The moisture adjusting device is a washing device that washes the reaction compatible material adhering to the reaction unsuitable material.

[0097] According to this configuration, the content of fermentation inhibitors in the reaction-compatible material can be reduced before the reaction-compatible material is supplied to the microbial reactor, thereby reducing the risk of reaction inhibition in the microbial reactor. Furthermore, by using the moisture adjustment device as a washing device for washing the reaction-unsuitable material, which is the large particle size component separated in the separation device, the small particle size component adhering to the reaction-unsuitable material can be recovered as reaction-compatible material, thereby improving the recovery rate of reaction-compatible material.

[0098]

[12] A waste treatment system according to another embodiment is the waste treatment system according to any one of [1] to

[10] , a dehydration device for dehydrating the residue of the microbial reaction device (3); a water injection pipe for supplying the water dehydrated in the dehydration device to at least one of the reformate before flowing into the separation device (4), the reformer (2), or the microbial reaction device (3); Equipped with.

[0099] With this configuration, the water obtained by dehydrating the residue of the microbial reactor contains ammonia, so if the nitrogen content in the waste in the reforming device or the contents in the microbial reactor is low, nitrogen-containing substances can also be replenished.

[0100]

[13] A waste treatment system according to another embodiment is the waste treatment system according to [8] to

[12] , The separator (4) is a screen that separates the modified product into large particle size components and small particle size components having particle sizes smaller than the large particle size components, and the large particle size components are the unsuitable for reaction.

[0101] If the microbial reactor is a composting device, it needs to have a low moisture content, so separation by a screen, as in the configuration of

[12] above, is suitable.

[0102]

[14] A waste treatment system according to yet another embodiment is any one of the waste treatment systems [1] to

[13] , a detector (controller 36) for detecting an indicator of the hydrolysis status of the waste material in the at least one reformer (2); an adjusting device (combustion boiler control device 32a / exhaust gas boiler control device 34a / steam supply amount adjusting valves 39a, 39b) for adjusting the hydrolysis conditions of the waste in the at least one reformer (2); A control device (36) and Furthermore, The control device (36) estimates the hydrolysis status of the waste based on the indicators detected by the detection device (control device 36), and operates the adjustment device (32a / 34a / 39a, 39b) to adjust the hydrolysis conditions of the waste based on the estimated hydrolysis status.

[0103] According to this configuration, a modified substance that meets the conditions suitable for the microbial reaction can be supplied to the microbial reaction device, so that valuable materials can be efficiently produced by the microbial reaction.

[0104]

[15] A waste treatment system according to another aspect is the waste treatment system according to

[14] , The at least one reformer (2) an agitator (16) for agitating the waste; a motor (17) for driving the agitator (16); Equipped with The detection device (36) detects the torque of the motor (17) as the indicator, The control device (36) estimates the hydrolysis status based on the torque of the motor (17).

[0105] According to this configuration, a modified substance that meets the conditions suitable for the microbial reaction can be supplied to the microbial reaction device, so that valuable materials can be efficiently produced by the microbial reaction.

[0106]

[16] A waste treatment system according to another aspect is the waste treatment system according to

[14] , The at least one reformer (2) an agitator (16) for agitating the waste; a motor (17) for driving the agitator (16); Equipped with The detection device (36) detects the current value of the motor (17) as the index, The control device (36) estimates the hydrolysis state based on the current value of the motor (17).

[0107] According to this configuration, a modified substance that meets the conditions suitable for the microbial reaction can be supplied to the microbial reaction device, so that valuable materials can be efficiently produced by the microbial reaction.

[0108]

[17] A waste treatment system according to another aspect is the waste treatment system according to

[14] , the detection device detects information about the properties of the waste as the indicator; The control device estimates the hydrolysis state based on the properties of the waste.

[0109] According to this configuration, a modified substance that meets the conditions suitable for the microbial reaction can be supplied to the microbial reaction device, so that valuable materials can be efficiently produced by the microbial reaction.

[0110]

[18] A waste treatment system according to another aspect is the waste treatment system according to

[17] , The control device learns the correspondence between the properties of the waste, the hydrolysis conditions, and the water decomposition state, and adjusts the hydrolysis conditions based on a trained model constructed as a result of the learning.

[0111] According to this configuration, valuable materials can be produced more efficiently through microbial reactions than in the above

[18] .

[0112]

[19] A waste treatment system according to another embodiment is the waste treatment system according to any one of

[14] to

[18] , the waste material is heated and hydrolyzed by steam supplied to the at least one reformer; The adjusting device adjusts at least one of the temperature, pressure, and supply amount of the steam.

[0113] According to this configuration, the hydrolysis conditions can be easily adjusted.

[0114]

[20] A waste treatment method according to one embodiment includes: hydrolyzing the waste material; a step of converting the hydrolyzed waste containing at least solids into smaller molecules using microorganisms; Includes.

[0115] According to the waste treatment method of the present disclosure, hydrolyzed waste can be broken down into smaller molecules by microorganisms to produce valuable materials without solid-liquid separation, so even waste with a low moisture content can be treated at low cost. [Explanation of symbols]

[0116] 1. Waste treatment system 2. Reformer 2a 1st reformer 2b Second reformer 3 Microbial reactor 4 Separation device 10. Cabinet 11 Inlet 12 Outlet 15 Jacket (heating part) 16 Mixer 17 Motor 18 On-off valve 19 On-off valve 36 Control device (detection device) 32a Combustion boiler control device (adjustment device) 34a Exhaust gas boiler control device (adjustment device) 35 Dehydration equipment 37 Water injection pipe (moisture adjustment device) 39a Steam supply volume adjustment valve (adjusting device) 39b Steam supply amount adjustment valve (adjusting device) 41 VFA sensor (detection device) 42 VFA sensor (detection device) 51 Fermentation inhibitor sensor (detection device) 70 Solid-liquid separator 71 Drying equipment (moisture adjustment equipment)

Claims

1. a reforming device for hydrolyzing the waste under conditions that inhibit the production of melanoidins; a microbial reaction device that uses microorganisms to reduce molecules of the modified product containing at least solids from the waste hydrolyzed in the reforming device; a separation device between the reforming device and the microbial reaction device, which separates unsuitable substances for reaction that are not suitable for degradation by the microorganisms in the microbial reaction device from the reformed substance; A waste treatment system comprising:

2. a reformer for hydrolyzing the waste material, the reformer including a first reformer and a second reformer; a solid-liquid separator for separating the waste material hydrolyzed in the first reforming device into solid and liquid; a microbial reaction device that uses microorganisms to reduce molecules of the modified product containing at least solids from the waste hydrolyzed in the reforming device; a separation device between the second reforming device and the microbial reaction device, which separates unsuitable reaction materials that are unsuitable for degradation by the microorganisms in the microbial reaction device from the reformed material; Equipped with In the second reforming device, only the solid separated in the solid-liquid separator is hydrolyzed.

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