Waste treatment system and method for operating said waste treatment system

Abstract

This waste treatment system is provided with: a hydrolysis device for hydrolyzing waste; a composting device for producing compost by fermenting a reactant that is waste that has been hydrolyzed in the hydrolysis device; and a moisture adjustment material supply device for supplying a moisture adjustment material to the waste, a reactant discharged from the hydrolysis device, or a reactant during fermentation in the composting device.

Description

Waste treatment system and method for operating this waste treatment system

[0001] This disclosure relates to a waste treatment system and a method for operating the waste treatment system. This application claims priority to Japanese Patent Application No. 2023-102123, filed with the Japan Patent Office on June 22, 2023, the contents of which are incorporated herein by reference.

[0002] Patent Document 1 describes a waste treatment system that hydrolyzes waste materials such as palm oil expeller effluent (POME) residue and palm empty fruit bunches (EFB) and produces organic fertilizer from the reaction product of the hydrolysis of the waste materials.

[0003] Japanese Patent Application Laid-Open No. 2020-163280

[0004] Generally, the production of organic fertilizer, i.e., composting, requires large-scale facilities and a long processing time. This is due to the slow reaction rate of composting, which is caused by the fact that the optimal reaction conditions are unknown, the method for adjusting the reaction conditions is unknown, and it is difficult to grasp the reaction conditions.

[0005] In view of the above circumstances, at least one embodiment of the present disclosure aims to provide a waste treatment system and an operating method for the waste treatment system that can improve the reaction rate of composting of reactants obtained by hydrolyzing waste.

[0006] In order to achieve the above object, the waste treatment system according to the present disclosure includes a hydrolysis device that hydrolyzes waste, a composting device that ferments the waste reactants hydrolyzed in the hydrolysis device to produce compost, and a moisture adjusting material supplying device that supplies a moisture adjusting material to the waste, the reactants discharged from the hydrolysis device, or the reactants being fermented in the composting device.

[0007] According to the waste treatment system of the present disclosure, the moisture content of the reactants fermented in the composting apparatus can be adjusted, thereby improving the composting reaction rate.

[0008] FIG. 1 is a schematic configuration diagram of a waste treatment system according to embodiment 1 of the present disclosure. FIG. 2 is a schematic configuration diagram of a waste treatment system according to embodiment 2 of the present disclosure. FIG. 3 is a schematic configuration diagram of a waste treatment system according to embodiment 4 of the present disclosure. FIG. 4 is a schematic configuration diagram of a waste treatment system according to embodiment 5 of the present disclosure. FIG. 5 is a schematic configuration diagram of a waste treatment system according to embodiment 6 of the present disclosure. FIG. 6 is a schematic configuration diagram of a waste treatment system according to embodiment 7 of the present disclosure. FIG. 7 is a schematic configuration diagram of a waste treatment system according to embodiment 8 of the present disclosure. FIG. 8 is a schematic configuration diagram of a waste treatment system according to embodiment 9 of the present disclosure.

[0009] A waste treatment system according to an embodiment of the present disclosure will be described below with reference to the drawings. The embodiment described below shows one aspect of the present disclosure, and is not intended to limit the present disclosure. Modifications can be made as desired within the scope of the technical concept of the present disclosure.

[0010] (Embodiment 1) <Configuration of a Waste Treatment System According to Embodiment 1 of the Present Disclosure> As shown in FIG. 1 , a waste treatment system 1 according to Embodiment 1 of the present disclosure includes a hydrolysis apparatus 2 that hydrolyzes waste, a composting apparatus 3 that ferments the reactants, which are the waste hydrolyzed in the hydrolysis apparatus 2, to produce compost, and a moisture-adjusting material supplying apparatus 4 that supplies a moisture-adjusting material to the reactants. The hydrolysis apparatus 2 may be configured with a single reactor, or may be configured with at least two reactors connected in series or parallel, or may be configured with at least two groups, each of which includes at least two reactors connected in series, connected in parallel. The configuration of the composting apparatus 3 is not particularly limited, and may be, for example, an area in which the reactants can be arranged as multiple ridges 3a on soil of any size. This example of the composting apparatus 3 employs a method known as the "windrow" method. However, the composting apparatus 3 may also be configured with a rotary kiln fermenter, a multi-stage fermenter, a silo fermenter, an auger fermenter, a bin fermenter, or the like.

[0011] The configuration of the moisture adjuster supplying device 4 is not particularly limited, and may be, for example, a configuration including a supply path 4a that supplies a moisture adjuster to a transfer path 5 that transports the reaction product discharged from the hydrolysis device 2 to the composting device 3, or a configuration including, in addition to the supply path 4a, a mixer 4b that is provided on the transfer path 5 downstream of the position where the supply path 4a connects to the transfer path 5. Alternatively, the moisture adjuster supplying device 4 may be provided with a branch path 4c branching off from the supply path 4a so that the moisture adjuster can be directly supplied to the ridges 3a of the composting device 3, and a supplying device capable of supplying the moisture adjuster to the ridges 3a may be provided or located at the downstream end of the branch path 4c. For example, such a supplying device may be a sprayer such as a shower if the moisture adjuster is a liquid or slurry, or may be a conveyor or heavy machinery that can move along the ridges 3a if the moisture adjuster is a solid. In addition, although Figure 1 shows the moisture-regulating material being supplied to only one ridge 3a via the branch path 4c, multiple branch paths 4c may be provided so that the moisture-regulating material can be supplied to all or some of the ridges 3a, or one branch path 4c may be configured to be able to move to each of multiple ridges 3a.

[0012] In the present disclosure, a "path" refers to a configuration for transporting reactants, waste materials, etc., and can be, for example, a pipe if the material being transported has fluidity, or a conveyor, heavy machinery, etc. if the material being transported is a solid material with no fluidity. In the former case where the "path" is a pipe, the "path" may include a device for fluidizing the material being transported, such as a pump or blower, depending on the material being transported.

[0013] The moisture adjuster is not particularly limited, and water, a solid or slurry containing moisture, or the like can be used. In the case where the waste is, for example, EFB, fresh fruit bunches (FFB) of oil palm are sterilized in a sterilization tank 101 in a palm oil mill 100, and then palm oil is extracted from the FFB, thereby discharging EFB and POME. The EFB is supplied as waste to the hydrolysis device 2 of the waste treatment system 1, and POME can be supplied as a moisture adjuster to the reactants by a moisture adjuster supply device 4. Water and POME are liquids or slurries that can be considered almost liquids, and therefore can be used as moisture adjusters to increase the moisture content of the reactants.

[0014] The waste treatment system 1 of Embodiment 8, which will be described later, includes a methane fermentation apparatus 13 that performs methane fermentation on a portion of the reactants discharged from the hydrolysis apparatus 2 (the methane fermentation apparatus 13 is not an essential component in Embodiment 1). The residue from methane fermentation in the methane fermentation apparatus 13 can also be supplied to the reactants as a moisture adjuster by the moisture adjuster supply device 4. The methane fermentation apparatus 13 can also perform methane fermentation on POME discharged from the palm oil mill 100, and can also supply POME anaerobic sludge, which is the residue from methane fermentation of POME, as a moisture adjuster to the reactants by the moisture adjuster supply device 4. Furthermore, when POME is treated as lagoon wastewater, the POME is separated into a solid phase and a liquid phase in the lagoon. In such a case, the liquid phase from the lagoon can be supplied to the methane fermentation apparatus 13 for methane fermentation, or the solid phase from the lagoon can be pumped out and supplied to the reactants as a moisture adjuster by the moisture adjuster supply device 4. Solid moisture conditioners such as methane fermentation residues or lagoon solid phase can be used as moisture conditioners to reduce the moisture content of the reactants, depending on their moisture content.

[0015] <Operation of the Waste Treatment System According to Embodiment 1 of the Present Disclosure> Next, the operation of the waste treatment system 1 according to Embodiment 1 of the present disclosure will be described. When waste (EFB, for example) is supplied to the reactor of the hydrolysis device 2, the waste is hydrolyzed by mixing the waste with the steam supplied to the reactor, or by heat exchange between the steam and the waste without mixing. When the reactant, which is the waste hydrolyzed in the hydrolysis device 2, is transferred to the composting device 3 via the transfer path 5, a moisture adjuster is supplied to the reactant from the moisture adjuster supply device 4. When the moisture content of the reactant is low, a moisture adjuster with a high moisture content, such as water or POME, is supplied. When the moisture content of the reactant is high, a moisture adjuster with a low moisture content, such as POME anaerobic sludge or lagoon solid phase, is supplied.

[0016] The reactants supplied with the moisture adjusting agent are transferred to the composting apparatus 3 via the transfer path 5. If a mixer 4b is provided on the transfer path 5, the reactants and moisture adjusting agent are thoroughly mixed in the mixer 4b before being transferred to the composting apparatus 3. The reactants transferred to the composting apparatus 3 are arranged in the form of ridges 3a and fermented to produce fertilizer. During fermentation, the ridges 3a are turned over as appropriate to maintain continuous contact with air. If the moisture adjusting agent supplying device 4 is equipped with a branch path 4c, the moisture adjusting agent is supplied to the ridges 3a even during fermentation, so that the moisture content of the ridges 3a can be maintained at a level suitable for fermentation.

[0017] It should be noted that the moisture content suitable for fermentation is not necessarily a range that can be determined universally for all waste treatment systems of any configuration, but rather varies depending on various factors such as the configuration and operating conditions of the waste treatment system 1, the environment of the location where the waste treatment system 1 is installed, the type of waste, etc. Generally, if the moisture content of the reactants is lower than the appropriate range, the growth of the fermenting microorganisms tends to be poor, which slows the composting reaction rate, while if the moisture content of the reactants is higher than the appropriate range, the reactants are less likely to come into contact with air, which tends to slow the composting reaction rate. For this reason, an appropriate range for the moisture content is set taking the above factors into consideration, and the moisture content of the ridges 3a is set to be within the appropriate range.

[0018] In this way, in the waste treatment system 1 according to the first embodiment of the present disclosure, the moisture content of the reactants fermented in the composting device 3 can be adjusted, thereby improving the composting reaction rate.

[0019] <Modification of the Waste Treatment System According to Embodiment 1 of the Present Disclosure> In Embodiment 1, a moisture adjuster is supplied to the reactants discharged from the hydrolysis apparatus 2 or to the reactants (ridges 3a) undergoing fermentation in the composting apparatus 3, but the present invention is not limited to this configuration. A moisture adjuster may also be supplied to the waste supplied to the hydrolysis apparatus 2 or to the waste before hydrolysis in the hydrolysis apparatus 2. For this purpose, the moisture adjuster supply apparatus 4 may be provided with a waste supply path 8 branching off from the supply path 4a and for supplying waste to the hydrolysis apparatus 2, or a branch path 4d communicating with the hydrolysis apparatus 2 or both. This modification is particularly effective when the hydrolysis apparatus 2 is configured so that waste is stored in a container (wire basket, etc.) without being mixed.

[0020] (Embodiment 2) Next, a waste treatment system according to embodiment 2 will be described. The waste treatment system according to embodiment 2 differs from embodiment 1 in that it is possible to supply an alkaline substance to the reactants being fermented in the composting apparatus 3. In embodiment 2, the same components as those in embodiment 1 are designated by the same reference numerals, and detailed description thereof will be omitted.

[0021] <Configuration of a Waste Treatment System According to Embodiment 2 of the Present Disclosure> As shown in Figure 2, a waste treatment system 1 according to Embodiment 2 of the present disclosure includes an alkaline substance supply device 6 for supplying an alkaline substance to the waste or the reactants in order to increase the pH of the reactants. The alkaline substance is not particularly limited, and examples that can be used include ammonium salts such as ammonium chloride and ammonium sulfate, slaked lime, quicklime, magnesia lime, calcium salts such as calcium carbonate, and sodium salts. The alkaline substance can be used in the form of a solution dissolved in a solvent such as water, a slurry dispersed in a solvent, or in the form of a powder or particles.

[0022] The configuration of the alkaline substance supply device 6 is not particularly limited, but when the alkaline substance is in the form of a solution or slurry, the alkaline substance supply device 6 may be configured to include a tank for storing the alkaline substance and a pump. When the alkaline substance is in the form of a powder or particles, the alkaline substance supply device 6 may be configured to include a tank for storing the alkaline substance and a blower for blowing the powder or particles or a feeder for intermittently discharging the powder or particles from the tank.

[0023] In order to supply an alkaline substance to the waste supplied to the hydrolysis apparatus 2, the alkaline substance supply device 6 may be configured to communicate with the waste supply path 8, which supplies the waste to the hydrolysis apparatus 2, via an alkaline substance supply line 7a. Furthermore, in order to supply an alkaline substance to the reactants discharged from the hydrolysis apparatus 2, the alkaline substance supply device 6 may be configured to communicate with the transfer path 5 via an alkaline substance supply line 7b. Furthermore, in order to supply an alkaline substance to the furrows 3a of the composting apparatus 3, the alkaline substance supply device 6 may be configured to include an alkaline substance supply line 7c having a sprayer attached to its downstream end capable of spraying an alkaline substance. Any two or all of the alkaline substance supply lines 7a, 7b, and 7c may be provided. Other configurations are the same as those of the first embodiment.

[0024] In this disclosure, the term "line" basically refers to a pipe or something similar to a pipe. Depending on the substance being transported, the term "line" may also include a device for moving the substance, such as a pump or a blower.

[0025] <Operation of Waste Treatment System According to Embodiment 2 of the Present Disclosure> Next, the operation of the waste treatment system 1 according to Embodiment 2 of the present disclosure will be described. When waste is hydrolyzed in the hydrolysis apparatus 2 using the same operation as in Embodiment 1, organic acids may be generated during hydrolysis, resulting in a decrease in the pH of the reactants. A decrease in the pH of the reactants slows down the composting reaction rate in the composting apparatus 3. In such cases, an alkaline substance is supplied from the alkaline substance supply apparatus 6 via alkaline substance supply lines 7a, 7b, and 7c to at least one of the waste supplied to the hydrolysis apparatus 2, the reactants transferred from the hydrolysis apparatus 2 to the composting apparatus 3, and the reactants (ridges 3a) undergoing fermentation in the composting apparatus 3. Other operations are the same as those in Embodiment 1.

[0026] During waste hydrolysis, organic acids can lower the pH of the reactants, potentially slowing the composting reaction rate. However, in the waste treatment system 1 according to the second embodiment of the present disclosure, supplying an alkaline substance to the reactants increases the pH of the reactants, thereby reducing the risk of a slowdown in the composting reaction rate. Furthermore, supplying an alkaline substance to the waste promotes the breakdown of organic matter into smaller molecules through hydrolysis, thereby increasing the amount of decomposition during composting and, as a result, improving the composting reaction rate. When an alkaline substance is supplied to the waste, the waste and alkaline substance are mixed within the hydrolysis device 2, eliminating the need for a separate device for mixing the two.

[0027] <Modification of the Waste Treatment System According to Embodiment 2 of the Present Disclosure> In Embodiment 2, an alkaline substance is supplied to the waste supplied to the hydrolysis apparatus 2, the reactant discharged from the hydrolysis apparatus 2, or the reactant (ridges 3a) undergoing fermentation in the composting apparatus 3, but the present invention is not limited to this configuration. For this purpose, an alkaline substance supply line 7d may be provided that connects the alkaline substance supply device 6 to the supply path 4a. The alkaline substance supply line 7d may be connected to the supply path 4a at a position upstream or downstream of the position where the branch path 4c branches off from the supply path 4a, or may be connected to the supply path 4a at both of these positions.

[0028] (Embodiment 3) Next, a waste treatment system according to embodiment 3 will be described. The waste treatment system according to embodiment 3 differs from embodiment 1 or 2 in that it is possible to supply a nitrogen-containing substance, which is a compound containing nitrogen, to the reactant being fermented in the composting apparatus 3. Hereinafter, embodiment 3 will be described as being configured to be able to supply a nitrogen-containing substance to embodiment 1, but embodiment 3 may also be configured to be able to supply a nitrogen-containing substance to embodiment 2. In embodiment 3, the same components as those in embodiment 1 are given the same reference numerals, and detailed description thereof will be omitted.

[0029] <Configuration of a Waste Treatment System According to Embodiment 3 of the Present Disclosure> As shown in Fig. 3 , a waste treatment system 1 according to Embodiment 3 of the present disclosure includes a nitrogen-containing substance supply device 9 for supplying nitrogen-containing compounds, which are compounds containing nitrogen, to waste or reactants in order to reduce the C / N ratio (ratio of carbon to nitrogen), which is an indicator of the composition of organic fertilizer produced in the composting device 3. The nitrogen-containing substance may be any substance having a C / N ratio lower than that of the waste to be hydrolyzed in the hydrolysis device 2. For example, ammonium salts such as ammonium chloride and ammonium sulfate, urea, and secondary materials such as cow dung can be used as the nitrogen-containing substance. The nitrogen-containing substance can be used in the form of a solution dissolved in a solvent such as water, a slurry dispersed in a solvent, or in the form of a powder or particles.

[0030] Although the configuration of the nitrogen-containing substance supplying device 9 is not particularly limited, when the nitrogen-containing substance is in the form of a solution or slurry, the nitrogen-containing substance supplying device 9 may be configured to include a tank for storing the nitrogen-containing substance and a pump. When the nitrogen-containing substance is in the form of a powder or particles, the nitrogen-containing substance supplying device 9 may be configured to include a tank for storing the nitrogen-containing substance and a blower for blowing the powder or particles or a feeder for intermittently discharging the powder or particles from the tank.

[0031] In order to supply a nitrogen-containing substance to the waste supplied to the hydrolysis apparatus 2, the nitrogen-containing substance supplying apparatus 9 may be configured to communicate with the waste supply path 8, which supplies the waste to the hydrolysis apparatus 2, via a nitrogen-containing substance supply line 9a. Furthermore, in order to supply a nitrogen-containing substance to the reactants discharged from the hydrolysis apparatus 2, the nitrogen-containing substance supplying apparatus 9 may be configured to communicate with the transfer path 5 via a nitrogen-containing substance supply line 9b. Furthermore, in order to supply a nitrogen-containing substance to the furrows 3a of the composting apparatus 3, the nitrogen-containing substance supplying apparatus 9 may be configured to include a nitrogen-containing substance supply line 9c having a sprayer attached to its downstream end capable of spraying the nitrogen-containing substance. Any two or all of the nitrogen-containing substance supply lines 9a, 9b, and 9c may be provided. Other configurations are the same as those of the first embodiment.

[0032] <Operation of Waste Treatment System According to Embodiment 3 of the Present Disclosure> Next, the operation of the waste treatment system 1 according to Embodiment 3 of the present disclosure will be described. Nitrogen-containing substances are supplied from the nitrogen-containing substance supply device 9 via nitrogen-containing substance supply lines 9a, 9b, and 9c to at least one of the waste supplied to the hydrolysis device 2, the reactants transferred from the hydrolysis device 2 to the composting device 3, and the reactants (ridges 3a) undergoing fermentation in the composting device 3. Other operations are the same as those of Embodiment 1.

[0033] The waste treatment system 1 according to the third embodiment of the present disclosure can reduce the C / N ratio of the organic fertilizer produced in the composting apparatus 3. When a nitrogen-containing substance is supplied to the waste, the waste and the nitrogen-containing substance are mixed in the hydrolysis apparatus 2, eliminating the need to provide a separate device for mixing the two.

[0034] (Embodiment 4) Next, a waste treatment system according to embodiment 4 will be described. The waste treatment system according to embodiment 4 is configured such that seed compost can be supplied to the reactants fermented in the composting apparatus 3, in contrast to any of embodiments 1 to 3. Hereinafter, embodiment 4 will be described as being configured such that seed compost can be supplied to embodiment 1, but embodiment 4 may also be configured such that seed compost can be supplied to embodiment 2 or 3. In embodiment 4, the same components as those in embodiment 1 are designated by the same reference numerals, and detailed description thereof will be omitted.

[0035] 4, the waste treatment system 1 according to the fourth embodiment of the present disclosure includes a seed compost supplying device 10 for supplying seed compost, specifically, a portion of the organic fertilizer produced by fermenting the reactants in the composting device 3, to the reactants. The configuration of the seed compost supplying device 10 is not particularly limited, but the seed compost supplying device 10 may include a tank for storing the seed compost, and a blower for blowing the seed compost or a feeder for intermittently discharging the seed compost from the tank.

[0036] In order to supply seed compost to the reactants in the hydrolysis apparatus 2 after completion of hydrolysis, the seed compost supplying device 10 may be configured to communicate with the waste supply path 8 for supplying waste to the hydrolysis apparatus 2 via a seed compost supply line 10a. Furthermore, in order to supply seed compost to the reactants discharged from the hydrolysis apparatus 2, the seed compost supplying device 10 may be configured to communicate with the transfer path 5 via a seed compost supply line 10b. Furthermore, in order to supply seed compost to the ridges 3a of the composting apparatus 3, the seed compost supplying device 10 may be configured to include a seed compost supply line 10c at the downstream end of which is attached or positioned a device capable of supplying seed compost to the ridges 3a (e.g., a conveyor or heavy machinery movable along the ridges 3a). Any two or all of the seed compost supply lines 10a, 10b, and 10c may be provided. Other configurations are the same as those of the first embodiment.

[0037] <Operation of Waste Treatment System According to Embodiment 4 of the Present Disclosure> Next, the operation of the waste treatment system 1 according to Embodiment 4 of the present disclosure will be described. Seed compost is supplied from the seed compost supply device 10 via seed compost supply lines 10a, 10b, and 10c to at least one of the reactants in the hydrolysis apparatus 2 after hydrolysis, the reactants being transferred from the hydrolysis apparatus 2 to the composting apparatus 3, and the reactants (ridges 3a) undergoing fermentation in the composting apparatus 3. Other operations are the same as those of Embodiment 1.

[0038] In the waste treatment system 1 according to the fourth embodiment of the present disclosure, supplying seed compost to the reactants can increase the composting reaction rate in the composting apparatus 3, thereby shortening the fermentation period of the reactants. When seed compost is supplied to the reactants in the hydrolysis apparatus 2 after hydrolysis, the reactants and seed compost are mixed within the hydrolysis apparatus 2, eliminating the need for a separate device for mixing the two. Furthermore, when seed compost is supplied to the reactants in the hydrolysis apparatus 2, if the temperature of the reactants is high, the heat will kill the microorganisms in the seed compost, preventing the effect of increasing the composting reaction rate. Therefore, it is necessary to wait until the temperature within the hydrolysis apparatus 2 has sufficiently decreased (to a temperature that will not kill the microorganisms in the seed compost) after hydrolysis is completed before supplying the seed compost to the reactants in the hydrolysis apparatus 2.

[0039] (Embodiment 5) Next, a waste treatment system according to Embodiment 5 will be described. The waste treatment system according to Embodiment 5 is configured by adding a temperature adjustment device to any of Embodiments 1 to 4, which adjusts the temperature of the reactants discharged from the hydrolysis apparatus 2 or the reactants undergoing fermentation in the composting apparatus 3. In the following, Embodiment 5 will be described as a configuration in which a temperature adjustment device is added to Embodiment 1, but it is also possible to configure Embodiment 5 by adding a temperature adjustment device to any of Embodiments 2 to 4. In Embodiment 5, the same components as those in Embodiment 1 are designated by the same reference numerals, and detailed description thereof will be omitted.

[0040] 5, the waste treatment system 1 according to the fifth embodiment of the present disclosure includes a temperature adjustment device 11 that adjusts the temperature of the reactants. The temperature adjustment device 11 may adjust the temperature of the reactants discharged from the hydrolysis device 2, or may adjust the temperature of the reactants (ridges 3a) undergoing fermentation in the composting device 3. In the former case, the temperature adjustment device 11 may include, for example, a heat source supply source 11a that is a storage or generation device that stores or generates a heat source such as steam, hot water, or biomass boiler exhaust gas, and a heat source supply line 11b that connects the heat source supply source 11a to the transfer path 5. In the latter case, the temperature adjustment device 11 may be configured to include, for example, a heat source flow line 11d through which the heat source flows under the ridges 3a, a heat source supply source 11a, a heat source supply line 11c connecting the heat source supply source 11a and the heat source flow line 11d, and a heat source outlet line 11e through which the heat source that has flowed through the heat source flow line 11d flows out of the composting device 3. While FIG. 5 shows the heat source flow line 11d as being provided only under one ridge 3a, the heat source flow line 11d may be provided under all or some of the ridges 3a. The temperature adjustment device 11 may also be configured to include both the former and latter configurations. Other configurations are the same as those in embodiment 1.

[0041] <Operation of Waste Treatment System According to Embodiment 5 of the Present Disclosure> Next, the operation of the waste treatment system 1 according to Embodiment 5 of the present disclosure will be described. The temperature adjustment device 11 adjusts the temperature of the reactants being transported along the transport path 5 or the reactants being fermented in the composting device 3. The preferred temperature range of the reactants depends on the state of the microorganisms in the composting device 3, but it is generally preferable to adjust the temperature so that the ridges 3a in the composting device 3 are approximately 60°C to 80°C. Other operations are the same as those in Embodiment 1.

[0042] When the temperature adjustment device 11 includes the heat source supply source 11a and the heat source supply line 11b, the reactants and the heat source are mixed during transport through the transport path 5, and the reactants are supplied to the composting apparatus 3 in a state adjusted to a preferred temperature range, allowing fermentation of the reactants within the preferred temperature range. On the other hand, when the temperature adjustment device 11 includes the heat source supply source 11a, the heat source supply line 11c, the heat source flow line 11d, and the heat source outlet line 11e, even if the reactants supplied to the composting apparatus 3 are not within the preferred temperature range, heat exchange between the heat source flowing through the heat source flow line 11d and the ridges 3a adjusts the temperature of the ridges 3a to a preferred range, allowing fermentation of the reactants within the preferred temperature range. This maintains an environment in which microorganisms that ferment the reactants can grow appropriately, thereby improving the composting reaction rate.

[0043] (Embodiment 6) Next, a waste treatment system according to Embodiment 6 will be described. The waste treatment system according to Embodiment 6 is configured by adding a crusher to crush a portion of the waste supplied to the hydrolysis apparatus 2 to any of Embodiments 1 to 5. In the following, Embodiment 6 will be described as a configuration in which a crusher is added to Embodiment 1, but it is also possible to configure Embodiment 6 by adding a crusher to any of Embodiments 2 to 5. In Embodiment 6, the same components as those in Embodiment 1 are designated by the same reference numerals, and detailed description thereof will be omitted.

[0044] <Configuration of a Waste Treatment System According to Embodiment 6 of the Present Disclosure> As shown in FIG. 6 , a waste treatment system 1 according to Embodiment 6 of the present disclosure includes a crusher 12 that crushes a portion of the waste supplied to the hydrolysis apparatus 2. The configuration of the crusher 12 is not particularly limited, and for example, a device that rotates multiple blades capable of cutting the waste into smaller chunks than the original size can be used. The crusher 12 is connected to the waste supply path 8 via a waste branch path 12a. A crushed waste supply path 12b is also connected to the crusher 12 so that the crushed waste can be supplied to the ridges 3a in the composting apparatus 3. A device (e.g., a conveyor or heavy machinery that can move along the ridges 3a) that can supply the crushed waste to the ridges 3a may be attached or located at the downstream end of the crushed waste supply path 12b. The remaining configuration is the same as that of Embodiment 1.

[0045] <Operation of Waste Treatment System According to Embodiment 6 of the Present Disclosure> Next, the operation of the waste treatment system 1 according to Embodiment 6 of the present disclosure will be described. A portion of the waste transported along the waste supply path 8 is supplied to the crusher 12 via the waste branch path 12a. The waste crushed by the crusher 12 is transported along the crushed waste supply path 12b and supplied to the ridges 3a in the composting device 3. Other operations are the same as those of Embodiment 1.

[0046] In the waste treatment system 1 according to the sixth embodiment of the present disclosure, the reactants (ridges 3a) and the crushed waste are mixed together and composted in the composting apparatus 3, which increases the contact between the reactants and air and improves the composting reaction rate. In addition, part of the waste is not supplied to the hydrolysis apparatus 2, which reduces the load on the hydrolysis apparatus 2.

[0047] (Embodiment 7) Next, a waste treatment system according to Embodiment 7 will be described. The waste treatment system according to Embodiment 7 is configured by adding a crusher to crush all of the waste supplied to the hydrolysis apparatus 2 to any of Embodiments 1 to 5. In the following, Embodiment 7 will be described as a configuration in which a crusher is added to Embodiment 1, but it is also possible to configure Embodiment 7 by adding a crusher to any of Embodiments 2 to 5. In Embodiment 7, the same components as those in Embodiment 1 are designated by the same reference numerals, and detailed description thereof will be omitted.

[0048] <Configuration of a waste treatment system according to embodiment 7 of the present disclosure> As shown in Fig. 7, in a waste treatment system 1 according to embodiment 7 of the present disclosure, a shredder 12 is provided in the waste supply path 8 to shred the waste to be supplied to the hydrolysis apparatus 2. The configuration of the shredder 12 in embodiment 7 is not particularly limited, and a shredder with the configuration exemplified in embodiment 6 can be used. A shredded waste supply path 12c branches off from the waste supply path 8 between the shredder 12 and the hydrolysis apparatus 2. A device capable of supplying shredded waste to the ridges 3a (e.g., a conveyor or heavy machinery movable along the ridges 3a) may be attached or located at the downstream end of the shredded waste supply path 12c. The other configurations are the same as those in embodiment 1.

[0049] <Operation of Waste Treatment System According to Embodiment 7 of the Present Disclosure> Next, the operation of the waste treatment system 1 according to Embodiment 7 of the present disclosure will be described. Waste transported along the waste supply path 8 is crushed in the crusher 12. A portion of the crushed waste is transported along the crushed waste supply path 12c and supplied to the ridges 3a in the composting device 3. A portion of the crushed waste is supplied to the hydrolysis device 2 and hydrolyzed. Other operations are the same as those of Embodiment 1.

[0050] In the waste treatment system 1 according to the seventh embodiment of the present disclosure, similarly to the sixth embodiment, the reactants (ridges 3a) and the crushed waste are mixed together in the composting apparatus 3 and composted, thereby increasing the contact between the reactants and air and improving the composting reaction rate. In addition, part of the waste is not supplied to the hydrolysis apparatus 2, thereby reducing the load on the hydrolysis apparatus 2.

[0051] (Embodiment 8) Next, a waste treatment system according to embodiment 8 will be described. The waste treatment system according to embodiment 8 is obtained by adding a methane fermentation apparatus that performs methane fermentation on a portion of the reaction product discharged from the hydrolysis apparatus to any of embodiments 1 to 7. In the following, embodiment 8 will be described as a configuration in which a methane fermentation apparatus is added to embodiment 1, but embodiment 8 may also be configured by adding a methane fermentation apparatus to any of embodiments 2 to 7. In embodiment 8, the same components as those in embodiment 1 are designated by the same reference numerals, and detailed description thereof will be omitted.

[0052] <Configuration of a waste treatment system according to embodiment 8 of the present disclosure> As shown in Fig. 8, a waste treatment system 1 according to embodiment 8 of the present disclosure includes a methane fermentation apparatus 13 that performs methane fermentation on a portion of the reactants discharged from the hydrolysis apparatus 2. The methane fermentation apparatus 13 is connected to the transfer path 5 via a reactant supply path 13a so that the reactants can be supplied to the methane fermentation apparatus 13. As described in embodiment 1, a branch line 103 branching from a POME supply line 102 extending from the palm oil mill 100 may be configured to communicate with the reactant supply path 13a so that the methane fermentation apparatus 13 can also perform methane fermentation on the POME discharged from the palm oil mill 100. The POME supply line 102 may also be configured to communicate with the supply path 4a. Furthermore, as described in embodiment 1, when POME is treated as lagoon wastewater, the branch line 103 may be a line for supplying the liquid phase of POME in the lagoon to the methane fermentation apparatus 13. In order to discharge the residue of methane fermentation from the methane fermentation device 13, a residue discharge path 13b is connected to the methane fermentation device 13, and the residue discharge path 13b may be configured to communicate with the supply path 4a.

[0053] The biogas produced by methane fermentation in the methane fermentation apparatus 13 may be used within the waste treatment system 1, may be used in a facility external to the waste treatment system 1, or may be stored in a storage facility for use in the waste treatment system 1 or in a facility external to the waste treatment system 1. When biogas is used in the waste treatment system 1, the waste treatment system 1 is equipped with a biogas utilization apparatus 14. When biogas is used in the waste treatment system 1 to generate steam to be used in the hydrolysis apparatus 2, the biogas utilization apparatus 14 is a steam generation apparatus, and the biogas utilization apparatus 14 and the methane fermentation apparatus 13 are connected via a biogas line 14a, and the biogas utilization apparatus 14 and the hydrolysis apparatus 2 are connected via a steam line 14b. In the waste treatment system 1, when biogas is used to generate steam or hot water to be used in the temperature adjustment device 11 of embodiment 5, the biogas utilization device 14 is a steam generation device or a hot water generation device, and the biogas utilization device 14 and the methane fermentation device 13 are connected via a biogas line 14a, and the biogas utilization device 14 and the heat source supply source 11a of the temperature adjustment device 11 are connected via a heat source supply line 14c. In this case, the biogas utilization device 14 may be configured to also serve as the heat source supply source 11a of the temperature adjustment device 11. When the biogas utilization device 14 is configured to also serve as the heat source supply source 11a of the temperature adjustment device 11, the heat source supply line 14c will constitute the heat source supply line 11b or 11c. The other configurations are the same as those of embodiment 1.

[0054] <Operation of Waste Treatment System According to Embodiment 8 of the Present Disclosure> Next, the operation of the waste treatment system 1 according to Embodiment 8 of the present disclosure will be described. A portion of the reactants discharged from the hydrolysis apparatus 2 is transferred to the methane fermentation apparatus 13 via the reactant supply path 13a and undergoes methane fermentation. In the methane fermentation apparatus 13, POME that has circulated from the palm oil mill 100 through the POME supply line 102 and branch line 103 may also be subjected to methane fermentation together with the reactants. After completion of methane fermentation, the residue within the methane fermentation apparatus 13 is discharged from the methane fermentation apparatus 13 via the residue discharge path 13b, and may be supplied to the reactants via the supply path 4a as a moisture adjusting material by the operation described in Embodiment 1.

[0055] In the waste treatment system 1 according to the eighth embodiment of the present disclosure, a methane fermentation apparatus 13 is provided in addition to the composting apparatus 3 as a device that uses reactants. Therefore, even if a malfunction occurs in the composting apparatus 3, the methane fermentation apparatus 13 can back up waste treatment, thereby preventing the waste treatment system 1 from being shut down or its treatment capacity from being reduced. Furthermore, when the waste is, for example, POME residue, POME anaerobic sludge is obtained as the residue from the methane fermentation. POME anaerobic sludge has a lower C / N ratio than POME, and therefore can reduce the C / N ratio of organic fertilizer.

[0056] When the biogas generated in the methane fermentation apparatus 13 is to be used or stored in equipment external to the waste treatment system 1, the biogas is supplied to a biogas utilization or storage facility via a biogas line (not shown). When the biogas generated in the methane fermentation apparatus 13 is to be used within the waste treatment system 1, the biogas is supplied to the biogas utilization apparatus 14 via the biogas line 14a. In the biogas utilization apparatus 14, for example, heat (energy) generated by burning the biogas is used to heat water to generate steam or hot water. By supplying the generated steam to the hydrolysis apparatus 2, it can be used as a heat source for hydrolysis of waste in the hydrolysis apparatus 2. By supplying the generated steam or hot water to the temperature adjustment device 11, it can be used as a heat source for adjusting the temperature of the reactants being transported along the transfer path 5 or the reactants being fermented in the composting apparatus 3. Other operations are the same as those in the first embodiment.

[0057] In this way, by using the steam generated in the biogas utilization device 14 as a heat source for hydrolysis of the waste in the hydrolysis device 2, the operating costs of the entire waste treatment system 1 can be reduced, and by using the steam or hot water generated in the biogas utilization device 14 as a heat source for adjusting the temperature of the reactants, the operating costs of the entire waste treatment system 1 can be reduced and the composting reaction rate can be improved.

[0058] (Embodiment 9) Next, a waste treatment system according to Embodiment 9 will be described. The waste treatment system according to Embodiment 9 is obtained by adding a solid-liquid separation device that separates the reaction product discharged from the hydrolysis apparatus into solid and liquid components to any of Embodiments 1 to 8. Hereinafter, Embodiment 9 will be described as a configuration in which a solid-liquid separation device is added to Embodiment 1, but Embodiment 9 may also be configured by adding a solid-liquid separation device to any of Embodiments 2 to 8. In Embodiment 9, the same components as those in Embodiment 1 are designated by the same reference numerals, and detailed description thereof will be omitted.

[0059] <Configuration of Waste Treatment System According to Embodiment 9 of the Present Disclosure> As shown in Fig. 9, the waste treatment system 1 according to Embodiment 9 of the present disclosure includes a solid-liquid separator 15 that separates the reaction product discharged from the hydrolysis apparatus 2 into solid and liquid. The configuration of the solid-liquid separator 15 is not particularly limited, and may be, for example, a filter or a centrifuge. In Embodiment 9, the transfer path 5 is configured to transfer the solid phase separated by the solid-liquid separator 15 to the composting apparatus 3. A storage device 16 may be provided that communicates with the solid-liquid separator 15 via a liquid phase line 18 to store the liquid phase separated by the solid-liquid separator 15. The storage device 16 may be connected to the supply path 4a via a line 17 so that the liquid phase stored in the storage device 16 can be used as a moisture adjusting material. When a methane fermentation apparatus 13 is provided, the entire amount of the liquid phase separated in the solid-liquid separation apparatus 15 is not stored in the storage apparatus 16, but a liquid phase branch line 18a branched from the liquid phase line 18 may be connected to the methane fermentation apparatus 13 so that part of the liquid phase can be supplied to the methane fermentation apparatus 13. The other configurations are the same as those of the first embodiment.

[0060] <Operation of Waste Treatment System According to Embodiment 9 of the Present Disclosure> Next, the operation of the waste treatment system 1 according to Embodiment 9 of the present disclosure will be described. The reaction product discharged from the hydrolysis apparatus 2 is separated into solid and liquid in the solid-liquid separator 15. The solid phase resulting from the solid-liquid separation is transferred to the composting apparatus 3 via the transfer path 5, and the moisture adjuster supply device 4 adjusts the moisture content of the transferred solid phase as needed, using the operation described in Embodiment 1. Meanwhile, the liquid phase resulting from the solid-liquid separation is stored in the storage device 16 and, as needed, is used as a moisture adjuster for adjusting the moisture content of the transferred solid phase. If a methane fermentation apparatus 13 is provided, a portion of the liquid phase is supplied to the methane fermentation apparatus 13 via the liquid phase branch line 18a and undergoes methane fermentation. The other operations are the same as those of Embodiment 1.

[0061] In the waste treatment system 1 according to the ninth embodiment of the present disclosure, only the solid phase separated by the solid-liquid separator 15 is supplied to the composting apparatus 3, which facilitates the transport of reactants to the composting apparatus 3. Furthermore, by using the liquid phase separated by the solid-liquid separator 15 as a moisture adjusting material, the transport of reactants to the composting apparatus 3 is facilitated and the composting reaction rate can be improved.

[0062] (Variations on the operation method of the waste treatment system according to each embodiment of the present disclosure) In embodiment 1, the operation of adjusting the moisture content of the reactants was described, in embodiment 2 the operation of increasing the pH of the reactants was described, in embodiment 3 the operation of decreasing the C / N ratio of the organic fertilizer produced in the composting apparatus 3 was described, and in embodiment 5 the operation of adjusting the temperature of the reactants was described, but these operations are not limited to being performed at the beginning of operation of the waste treatment system 1. The moisture, pH, C / N ratio, and temperature of the ridges 3 a in the composting apparatus 3 change over time during the operation of the waste treatment system 1, so these adjustments may be made continuously or intermittently during the operation of the waste treatment system 1. In order to continuously adjust these values ​​during operation, for example, a measuring device such as a sensor for measuring the moisture, pH, C / N ratio, and temperature of the ridges 3a in the composting apparatus 3 may be provided, or the reactants during fermentation may be continuously sampled from the ridges 3a at appropriate intervals and measured, and the moisture, pH, C / N ratio, and temperature of the ridges 3a in the composting apparatus 3 may be adjusted by the operations described in embodiments 1 to 3 and 5 so that the measured values ​​fall within a predetermined range.

[0063] Immediately after the start of fermentation of the reactants in the composting apparatus 3, the amount of reactants being fermented is large, and therefore the composting reaction rate is high. Therefore, oxygen shortages are likely to occur as the composting reaction progresses. To detect such oxygen shortages early, it is preferable to continuously detect the oxygen concentration within the ridges 3a. For example, a measuring device such as a sensor for measuring the oxygen concentration within the ridges 3a may be provided, or the reactants undergoing fermentation may be continuously sampled from the ridges 3a at appropriate intervals to measure the oxygen concentration within the reactants. If a risk of oxygen shortage is detected, the number of times the ridges 3a are turned over may be increased, or, if a device for supplying air to the ridges 3a is provided, the amount of air supplied to the ridges 3a may be increased.

[0064] On the other hand, as the fermentation of the reactants progresses, the amount of fermented reactants decreases, making oxygen shortages less likely to occur. Conversely, heat dissipation due to the supply of air to the ridges 3a occurs, lowering the temperature of the reactants and potentially slowing the composting reaction rate. For this reason, once the fermentation of the reactants progresses, it is preferable to reduce the number of times the ridges 3a are turned over, or to reduce or stop the amount of air supplied to the ridges 3a. Furthermore, as the fermentation of the reactants progresses, it becomes more difficult for the temperature of the reactants to rise, so it is effective to heat the ridges 3a using the operation of embodiment 5 or to take measures to dissipate heat from the ridges 3a. One measure to dissipate heat from the ridges 3a is, for example, to surround both sides of the ridges 3a with walls containing insulating material.

[0065] The pH, temperature, and oxygen concentration of the ridges 3a in the composting apparatus 3 are preferably adjusted by adjusting the alkaline material supply rate, heat source supply rate (corresponding to the rate of change in temperature of the ridges 3a), and air supply rate based on differences from preset conditions. To achieve this, the composting reaction is simulated based on a simulation model that conforms to a physical model established based on biological reaction kinetics, heat balance, material balance, and prior experimental results. This simulation model can then be used to make adjustments based on differences from preset conditions. Using the simulation model allows for quantitative determination of the adjustment range and effect of the operating conditions of the waste treatment system 1, thereby maintaining a higher composting reaction rate than methods relying on trial and error. Note that the model coefficients in the physical model may be optimized using statistical techniques or machine learning.

[0066] The contents described in each of the above embodiments can be understood, for example, as follows.

[0067] [1] A waste treatment system according to one embodiment includes a hydrolysis apparatus (2) for hydrolyzing waste, a composting apparatus (3) for fermenting the waste product, which is a reactant hydrolyzed in the hydrolysis apparatus (2), to produce compost, and a moisture adjusting material supplying apparatus (4) for supplying a moisture adjusting material to the waste product, the reactant discharged from the hydrolysis apparatus (2), or the reactant being fermented in the composting apparatus (3).

[0068] According to the waste treatment system of the present disclosure, the moisture content of the reactants fermented in the composting apparatus can be adjusted, thereby improving the composting reaction rate.

[0069] [2] A waste treatment system according to another aspect is the waste treatment system of [1], further comprising an alkaline substance supplying device (6) that supplies an alkaline substance to the waste, the reactants discharged from the hydrolysis device (2), the reactants undergoing fermentation in the composting device (3), or the moisture adjusting material.

[0070] With this configuration, during waste hydrolysis, organic acids can lower the pH of the reactants, potentially slowing the composting reaction rate. However, by supplying an alkaline substance to the reactants, the pH of the reactants increases, thereby preventing a decrease in the composting reaction rate. Furthermore, supplying an alkaline substance to the waste promotes the breakdown of organic matter into smaller molecules through hydrolysis, thereby increasing the amount of decomposition during composting and, as a result, improving the composting reaction rate. When an alkaline substance is supplied to the waste, the waste and alkaline substance are mixed within the hydrolysis apparatus, eliminating the need for a separate device for mixing the two.

[0071] [3] A waste treatment system according to yet another embodiment is the waste treatment system of [1] or [2], further comprising a nitrogen-containing substance supplying device (9) that supplies a nitrogen-containing substance, which is a compound containing nitrogen, to the waste, the reactant discharged from the hydrolysis device (2), or the reactant being fermented in the composting device (3).

[0072] This configuration can reduce the C / N ratio (ratio of carbon to nitrogen), which is an index of the composition of the organic fertilizer produced in the composting system. When nitrogen-containing substances are added to the waste, the waste and the nitrogen-containing substances are mixed in the hydrolysis system, eliminating the need for a separate device for mixing the two.

[0073] [4] A waste treatment system according to yet another embodiment is the waste treatment system according to any one of [1] to [3], further comprising a seed compost supplying device (10) that supplies seed compost to the reactants in the hydrolysis device (2), the reactants discharged from the hydrolysis device (2), or the reactants undergoing fermentation in the composting device (3).

[0074] According to this configuration, by supplying seed compost to the reactants, the composting reaction rate in the composting apparatus can be increased, thereby shortening the fermentation period of the reactants. When seed compost is supplied to the reactants in the hydrolysis apparatus after hydrolysis, the reactants and seed compost are mixed within the hydrolysis apparatus, eliminating the need for a separate device for mixing the two.

[0075] [5] A waste treatment system according to yet another embodiment is the waste treatment system according to any one of [1] to [4], further comprising a temperature adjustment device (11) for adjusting the temperature of the reactants discharged from the hydrolysis device (2) or the reactants undergoing fermentation in the composting device (3).

[0076] According to this configuration, by adjusting the temperature of the reactants, an environment can be maintained in which the microorganisms that ferment the reactants can grow appropriately, thereby improving the composting reaction rate.

[0077] [6] A waste treatment system according to yet another embodiment is the waste treatment system of any one of [1] to [5], further comprising a crusher (12) for crushing a portion of the waste to be supplied to the hydrolysis device (2), and the waste crushed by the crusher (12) is supplied to the composting device (3).

[0078] With this configuration, the reactants and the crushed waste are mixed together in the composting apparatus and composted, increasing the contact between the reactants and air and improving the composting reaction rate. Also, since part of the waste is not supplied to the hydrolysis apparatus, the load on the hydrolysis apparatus can be reduced.

[0079] [7] A waste treatment system according to yet another embodiment is the waste treatment system of any one of [1] to [5], further comprising a crusher (12) for crushing the waste to be supplied to the hydrolysis device (2), and is configured such that a portion of the waste crushed by the crusher (12) is supplied to the composting device (3) and a portion is supplied to the hydrolysis device (2).

[0080] With this configuration, the reactants and the crushed waste are mixed together in the composting apparatus and composted, increasing the contact between the reactants and air and improving the composting reaction rate. Also, since part of the waste is not supplied to the hydrolysis apparatus, the load on the hydrolysis apparatus can be reduced.

[0081] [8] A waste treatment system according to yet another embodiment is the waste treatment system according to any one of [1] to [7], further comprising a methane fermentation apparatus (13) for methane fermenting a portion of the reaction product discharged from the hydrolysis apparatus (2).

[0082] With this configuration, even if the composting apparatus breaks down, the methane fermentation apparatus can back up waste treatment, preventing the waste treatment system from being shut down or its treatment capacity from being reduced.

[0083] [9] A waste treatment system according to yet another embodiment is the waste treatment system of [8], wherein the moisture adjusting material supply device (4) supplies a residue from methane fermentation in the methane fermentation device (13) as the moisture adjusting material to the reactant.

[0084] According to this configuration, when the waste is, for example, POME residue, POME anaerobic sludge is obtained as the residue of methane fermentation. POME anaerobic sludge has a lower C / N ratio than POME, so the C / N ratio of the organic fertilizer can be reduced.

[0085]

[10] A waste treatment system according to yet another embodiment is the waste treatment system of [8] or [9], further comprising a biogas utilization device (14) that generates energy by utilizing biogas produced by methane fermentation in the methane fermentation device (13), and at least a part of the energy is used as a heat source for hydrolysis of the waste in the hydrolysis device (2).

[0086] With this configuration, the operating costs of the entire waste treatment system can be reduced.

[0087]

[11] A waste treatment system according to yet another embodiment is the waste treatment system of [8] or [9], comprising: a temperature control device (11) that controls the temperature of the reactants discharged from the hydrolysis device (2) or the reactants undergoing fermentation in the composting device (3); and a biogas utilization device (14) that generates energy by utilizing biogas produced by methane fermentation in the methane fermentation device (13), and at least a part of the energy is used as a heat source for the temperature control device (11).

[0088] With this configuration, the operating costs of the entire waste treatment system can be reduced and the composting reaction rate can be improved.

[0089]

[12] A waste treatment system according to yet another embodiment is the waste treatment system of [1], further comprising a solid-liquid separator (15) for separating the reaction product discharged from the hydrolysis apparatus (2) into solid and liquid phases, and the solid phase separated by the solid-liquid separator (15) is supplied to the composting apparatus (13).

[0090] According to this configuration, only the solid phase separated by the solid-liquid separator is supplied to the composting apparatus, which makes it easier to transport the reactants to the composting apparatus.

[0091]

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

[12] , wherein the liquid phase separated in the solid-liquid separator (15) is used as at least a part of the moisture adjusting material.

[0092] This configuration makes it easier to transport the reactants to the composting device and improves the composting reaction rate.

[0093]

[14] A method for operating a waste treatment system according to one aspect is a method for operating a waste treatment system (1) according to any one of [1] to

[13] , comprising the steps of measuring the moisture content of the reactants undergoing fermentation in the composting device (3), and supplying the moisture adjusting material so that the moisture content of the reactants undergoing fermentation in the composting device (3) is within a preset range.

[0094] According to the method for operating a waste treatment system of the present disclosure, the moisture content of the reactants fermented in the composting apparatus can be adjusted, thereby improving the composting reaction rate.

[0095]

[15] A method for operating a waste treatment system according to one aspect is a method for operating the waste treatment system (1) of [2], comprising the steps of measuring the pH of the reactants during fermentation in the composting device (3), and supplying the alkaline substance so that the pH of the reactants during fermentation in the composting device (3) falls within a predetermined range.

[0096] According to this operating method, there is a risk that the pH of the reactants will decrease due to organic acids during the hydrolysis of waste, which could result in a slower composting reaction rate. However, by supplying an alkaline substance to the reactants, the pH of the reactants will increase, thereby preventing a slowdown in the composting reaction rate.

[0097]

[16] A method for operating a waste treatment system according to one aspect is a method for operating the waste treatment system (1) of [3], comprising the steps of measuring the C / N ratio of the reactants during fermentation in the composting device (3), and supplying the nitrogen-containing substance so that the C / N ratio of the reactants during fermentation in the composting device (3) is within a predetermined range.

[0098] According to this operating method, it is possible to reduce the C / N ratio (ratio of carbon to nitrogen), which is an index of the composition of the organic fertilizer produced in the composting apparatus.

[0099]

[17] A method for operating a waste treatment system according to one aspect is a method for operating the waste treatment system (1) of [5], comprising the steps of: measuring the temperature of the reactants undergoing fermentation in the composting device (3); and adjusting the temperature of the reactants undergoing fermentation in the composting device (3) so that the temperature of the reactants falls within a preset range.

[0100] According to this operating method, by adjusting the temperature of the reactants, an environment can be maintained in which the microorganisms that ferment the reactants can grow appropriately, thereby improving the composting reaction rate.

[0101]

[18] A method for operating a waste treatment system according to one aspect is a method for operating the waste treatment system (1) of [2], comprising the steps of: measuring the pH of the reactants undergoing fermentation in the composting device (3); and adjusting the supply rate of the alkaline substance based on the difference between the pH of the reactants undergoing fermentation in the composting device (3) and a preset condition.

[0102] According to this operating method, the supply rate of the alkaline substance can be adjusted more smoothly than in the operating method

[15] .

[0103]

[19] A method for operating a waste treatment system according to one aspect is a method for operating the waste treatment system (1) of [5], comprising the steps of: measuring the temperature of the reactants during fermentation in the composting device (3); and adjusting the rate of change in the temperature of the reactants based on a difference between the temperature of the reactants during fermentation in the composting device (3) and a preset condition.

[0104] According to this operating method, the rate of change in the temperature of the reactants can be adjusted more smoothly than in the operating method

[17] .

[0105]

[20] A method for operating a waste treatment system according to one aspect is a method for operating the waste treatment system (1) according to any one of [1] to

[13] , comprising the steps of: measuring the oxygen concentration in the reactants undergoing fermentation in the composting device (3); and adjusting the rate at which air is supplied to the reactants based on the difference between the oxygen concentration in the reactants undergoing fermentation in the composting device (3) and a preset condition.

[0106] According to this operating method, the rate at which air is supplied to the reactants can be adjusted more smoothly than in the operating method

[14] .

[0107]

[21] Another aspect of the method for operating a waste treatment system is the method for operating a waste treatment system according to any one of

[18] to

[20] , further comprising a step of setting the conditions, wherein the step of setting the conditions includes simulating the composting reaction based on a simulation model that conforms to a physical model set based on biological reaction kinetics, heat balance, material balance, and previous experimental results, and utilizing the simulation model.

[0108] This operating method allows the temperature and pH of the reactants during fermentation in the composting apparatus, as well as the adjustment range and effect of the oxygen concentration in the reactants, to be quantitatively determined, thereby making it possible to maintain a higher composting reaction rate than methods that rely on trial and error.

[0109] REFERENCE SIGNS LIST 1 Waste treatment system 2 Hydrolysis device 3 Composting device 4 Moisture adjusting material supply device 6 Alkaline substance supply device 9 Nitrogen-containing substance supply device 10 Seed compost supply device 11 Temperature control device 12 Crusher 13 Methane fermentation device 14 Biogas utilization device 15 Solid-liquid separation device

Claims

1. A waste treatment system comprising: a hydrolysis apparatus for hydrolyzing waste; a composting apparatus for fermenting a reactant, which is the waste hydrolyzed in the hydrolysis apparatus, to produce compost; and a moisture adjusting material supplying apparatus for supplying a moisture adjusting material to the waste, the reactant discharged from the hydrolysis apparatus, or the reactant being fermented in the composting apparatus.

2. The waste treatment system according to claim 1, further comprising an alkaline substance supplying device that supplies an alkaline substance to the waste, the reactants discharged from the hydrolysis device, the reactants being fermented in the composting device, or the moisture adjusting material.

3. The waste treatment system according to claim 1, further comprising a nitrogen-containing substance supplying device that supplies a nitrogen-containing substance, which is a compound containing nitrogen, to the waste, the reactants discharged from the hydrolysis device, or the reactants being fermented in the composting device.

4. The waste treatment system of claim 1, further comprising a seed compost supplying device that supplies seed compost to the reactants in the hydrolysis device, the reactants discharged from the hydrolysis device, or the reactants being fermented in the composting device.

5. The waste treatment system according to claim 1, further comprising a temperature adjusting device for adjusting the temperature of the reactants discharged from the hydrolysis device or the reactants undergoing fermentation in the composting device.

6. The waste treatment system according to claim 1, further comprising a crusher for crushing a portion of the waste to be supplied to the hydrolysis apparatus, and the waste crushed by the crusher is configured to be supplied to the composting apparatus.

7. The waste treatment system according to claim 1, further comprising a crusher for crushing the waste to be supplied to the hydrolysis apparatus, and wherein a portion of the waste crushed by the crusher is supplied to the composting apparatus and a portion of the waste is supplied to the hydrolysis apparatus.

8. The waste treatment system according to any one of claims 1 to 7, further comprising a methane fermentation device for performing methane fermentation on a part of the reactants discharged from the hydrolysis device.

9. The waste treatment system according to claim 8, wherein the moisture adjusting material supplying device is configured to supply a residue of methane fermentation in the methane fermentation device as the moisture adjusting material to the reactants.

10. The waste treatment system according to claim 8, further comprising a biogas utilization device that generates energy by utilizing the biogas produced by methane fermentation in the methane fermentation device, and at least a portion of the energy is used as a heat source for hydrolysis of the waste in the hydrolysis device.

11. The waste treatment system according to claim 8, comprising: a temperature adjustment device that adjusts the temperature of the reactants discharged from the hydrolysis device or the reactants being fermented in the composting device; and a biogas utilization device that generates energy by utilizing the biogas produced by methane fermentation in the methane fermentation device, wherein at least a part of the energy is used as a heat source for the temperature adjustment device.

12. The waste treatment system according to claim 1, further comprising a solid-liquid separation device for separating the reactants discharged from the hydrolysis device into solid and liquid, and the solid phase separated by the solid-liquid separation device is supplied to the composting device.

13. The waste treatment system according to claim 12, wherein the liquid phase separated in the solid-liquid separation device is used as at least a part of the moisture adjusting material.

14. A method for operating a waste treatment system as claimed in any one of claims 1 to 7, 12 and 13, comprising the steps of: measuring the moisture content of the reactants undergoing fermentation in the composting apparatus; and supplying the moisture adjusting material so that the moisture content of the reactants undergoing fermentation in the composting apparatus falls within a preset range.

15. A method for operating a waste treatment system as described in claim 2, comprising the steps of: measuring the pH of the reactants undergoing fermentation in the composting apparatus; and supplying the alkaline substance so that the pH of the reactants undergoing fermentation in the composting apparatus is within a preset range.

16. A method for operating a waste treatment system as described in claim 3, comprising the steps of: measuring the C / N ratio of the reactant undergoing fermentation in the composting apparatus; and supplying the nitrogen-containing material so that the C / N ratio of the reactant undergoing fermentation in the composting apparatus is within a preset range.

17. A method for operating a waste treatment system as described in claim 5, comprising the steps of: measuring the temperature of the reactants undergoing fermentation in the composting apparatus; and adjusting the temperature of the reactants undergoing fermentation in the composting apparatus so that the temperature of the reactants undergoing fermentation is within a preset range.

18. A method for operating a waste treatment system as described in claim 2, comprising the steps of: measuring a pH of the reactant being fermented in the composting apparatus; and adjusting a supply rate of the alkaline substance based on a difference between the pH of the reactant being fermented in the composting apparatus and a preset condition.

19. A method for operating a waste treatment system as described in claim 5, comprising the steps of: measuring the temperature of the reactants undergoing fermentation in the composting apparatus; and adjusting a rate of change of the temperature of the reactants based on a difference between the temperature of the reactants undergoing fermentation in the composting apparatus and a preset condition.

20. A method for operating a waste treatment system as described in claim 1, comprising the steps of: measuring an oxygen concentration within the reactants undergoing fermentation in the composting device; and adjusting a rate of air supply to the reactants based on a difference between the oxygen concentration within the reactants undergoing fermentation in the composting device and a preset condition.

21. An operating method according to any one of claims 18 to 20, comprising a step of setting the conditions, the step of setting the conditions including simulating a composting reaction based on a simulation model conforming to a physical model set based on biological reaction kinetics, heat balance, material balance, and results of previous experiments, and utilizing the simulation model.

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