Waste treatment system and waste treatment method

Abstract

To provide a waste treatment system and a waste treatment method that can quickly meet a request for vapor from a reforming device.SOLUTION: This waste treatment system is provided with: at least one reforming device that hydrolyzes waste with vapor; a microbial reaction device that reduces, using microorganisms, the molecular weight of a reformed substance including at least a solid matter from the waste hydrolyzed by the at least one reforming device; and at least one vapor generation device that generates vapor using only the combustion energy of the gas generated in the microbial reaction device.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a waste treatment system and a waste treatment method. [Background technology]

[0002] There is a demand for effective utilization of unused biomass, such as urban waste discharged from households and food factories, agricultural waste such as rice straw, wheat straw, palm residue, livestock manure, sewage sludge, etc. For example, in the technology described in Patent Document 1, waste is hydrothermally treated (hydrolyzed) with steam in a reforming device, and solid fuel is produced from the solid phase of the reaction product obtained by this hydrolysis. Then, steam is generated using the combustion energy generated by burning the solid fuel, and the above hydrolysis is carried out using the generated steam. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Special Publication No. 2013-511386 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the technology described in Patent Document 1, steam is generated using combustion energy produced by burning solid fuel, so the steam demand from the reformer cannot be met quickly, and there is a risk that the reformer will go into standby mode.

[0005] The present disclosure has been made in consideration of the above-mentioned problems, and aims to provide a waste treatment system and a waste treatment method that can quickly satisfy the demand for steam from a reformer. [Means for solving the problem]

[0006] In order to achieve the above-mentioned objective, the waste treatment system according to the present disclosure comprises at least one reforming device that hydrolyzes waste with steam, a microbial reaction device that uses microorganisms to convert the reformate containing at least solids from the waste hydrolyzed in the at least one reforming device into smaller molecules, and at least one steam generation device that generates the steam using only the combustion energy of gas produced in the microbial reaction device.

[0007] In order to achieve the above-mentioned objective, the waste treatment method disclosed herein comprises the steps of hydrolyzing waste with steam, converting a modified product of the hydrolyzed waste, which contains at least solids, into smaller molecules using microorganisms, and generating the steam using only the combustion energy of the gas produced in the step of converting the modified product into smaller molecules using microorganisms. Effect of the Invention

[0008] According to the waste treatment system and waste treatment method of the present disclosure, the demand for steam from the reformer can be quickly met. [Brief description 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. [Diagram 2] FIG. 11 is a schematic diagram showing the configuration of a waste treatment system according to a second embodiment of the present disclosure. [Diagram 3] FIG. 11 is a schematic diagram showing the configuration of a waste treatment system according to a third embodiment of the present disclosure. [Figure 4] FIG. 11 is a schematic diagram showing the configuration of a waste treatment system according to a fourth embodiment of the present disclosure. [Diagram 5] FIG. 11 is a schematic diagram showing the configuration of a waste treatment system according to a fifth embodiment of the present disclosure. [Figure 6] 1 is a schematic diagram showing part of a configuration of a waste treatment system according to an embodiment of the present disclosure, illustrating the peripheral configuration of a reforming device. [Figure 7A]4 is a graph showing the relationship between the amount of steam supplied to a first reformer and time according to an embodiment of the present disclosure. [Figure 7B] 4 is a graph showing the relationship between the amount of steam supplied to the second reformer and time according to an embodiment of the present disclosure. [Figure 8] 1 is a flow chart of a waste treatment method according to an embodiment of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, a waste treatment system and a waste treatment method according to an embodiment of the present disclosure will be described with reference to the drawings. The embodiment shows one aspect of the present disclosure, and does not limit the present disclosure. The embodiment can be arbitrarily modified within the scope of the technical idea of ​​the present disclosure.

[0011] (Embodiment 1) <Configuration of waste treatment system according to embodiment 1> Fig. 1 is a schematic diagram of a waste treatment system 1 according to the first embodiment of the present disclosure. As shown in Fig. 1, the waste treatment system 1 according to the first embodiment of the present disclosure includes a reformer 2, a microbial reaction device 3, and a steam generator 4.

[0012] The reformer 2 hydrolyzes the waste with steam S1. The reformer 2 receives waste as is from a vehicle or a plant that collects waste such as urban waste, and hydrolyzes the waste in a batchwise manner with steam S1. Specifically, the reformer 2 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 hydrolyzed waste is discharged. The inlet 11 and the outlet 12 are each provided with an on-off valve (not shown), and the housing 10 can be sealed by closing each of the on-off valves. The hydrolysis of the waste in the reformer 2 may be wet hydrolysis in which the steam S1 comes into contact with the waste and heats it, or dry hydrolysis in which the steam S1 does not come into contact with the waste and indirectly heats it. In the case of dry hydrolysis, the moisture in the waste in the housing 10 evaporates to become water vapor, and the waste in the housing 10 is uniformly heated by the water vapor. In addition, moisture is necessary for hydrolysis, and the moisture is supplied by the water vapor adhering to the surface of the waste. Although FIG. 1 shows one reformer 2, the configuration may be such that a plurality of reformers 2 are connected in series, a plurality of reformers 2 are connected in parallel, or a configuration in which the series-connected configuration and the parallel-connected configuration are combined.

[0013] Municipal waste, given as an example of waste, is mainly composed of food waste, paper waste, and plastic waste, and also contains small amounts of metal. The waste treated by the waste treatment system 1 is not limited to municipal waste, and waste with a higher water content than municipal waste, such as sludge generated by treating wastewater from factories, etc., and agricultural waste, can also be treated by the waste treatment system 1.

[0014] The microbial reaction device 3 uses microorganisms to break down the reformed material X1, which is at least a solid, from the waste hydrolyzed in the reformer 2 into smaller molecules. At this time, the microbial reaction device 3 generates a biogas G1. The microbial reaction device 3 may have any configuration as long as it uses the reformed material X1 as a raw material and generates a biogas G1 by utilizing the biological action of microorganisms. For example, the microbial reaction device 3 is a biogas fermenter that generates a biogas G1 such as methane as a valuable resource. However, the microbial reaction device 3 is not limited to a biogas fermenter. For example, the microbial reaction device 3 may be a saccharification tank that produces sugar as a valuable resource from carbohydrates such as starch and cellulose, or a composting device that produces compost by composting. Note that, according to the configuration illustrated in FIG. 1, the waste hydrolyzed in the reformer 2 can be broken down into smaller molecules in the microbial reaction device 3 without solid-liquid separation to generate valuable resources, so that the waste treatment system 1 can treat even waste with a low moisture content at low cost.

[0015] The steam generator 4 generates steam S1 using only the combustion energy of the biogas G1 generated in the microbial reaction device 3. In other words, the steam generator 4 does not generate steam S1 using the combustion energy of fuel other than the biogas G1 generated in the microbial reaction device 3. The reformer 2 hydrolyzes waste with the steam S1 generated in the steam generator 4. Such a steam generator 4 includes, for example, an exhaust gas boiler. The exhaust gas boiler generates steam S1 using the heat of exhaust gas generated by the combustion of the biogas G1. The steam generator 4 is not limited to the exhaust gas boiler. Instead of the exhaust gas boiler, the steam generator 4 may include a combustion boiler that generates steam S1 using the biogas G1 as fuel. The steam generator 4 may also include both an exhaust gas boiler and a combustion boiler.

[0016] <Actions and Effects of the Waste Treatment System According to the First Embodiment> The action and effect of the waste treatment system 1 according to the first embodiment of the present disclosure will be described. Gaseous fuel burns faster than solid or liquid fuel. According to the first embodiment, the reformer 2 performs hydrolysis with steam generated using only the combustion energy of the biogas G1 generated in the microbial reaction device 3. Therefore, the demand for steam S1 from the reformer 2 can be quickly met.

[0017] When the reformer 2 hydrolyzes waste with a low moisture content (e.g., municipal waste) to produce a reformed product X1, the amount of biogas G1 produced may be greater when the solids contained in the reformed product X1 are converted into smaller molecules by microorganisms than when only the liquid contained in the reformed product X1 is converted into smaller molecules by microorganisms. According to the first embodiment, the microbial reaction device 3 converts the reformed product X1, which contains at least solids among the waste hydrolyzed in the reformer 2, into smaller molecules by microorganisms. This makes it possible to increase the amount of biogas G1 produced.

[0018] (Embodiment 2) Next, a waste treatment system 1 according to embodiment 2 will be described. The waste treatment system 1 according to embodiment 2 is obtained by adding a heat-retaining steam pipe 8 to embodiment 1. In embodiment 2, the same components as those in embodiment 1 are given the same reference symbols, and detailed descriptions thereof will be omitted.

[0019] <Configuration of waste treatment system according to embodiment 2> 2 is a schematic diagram of a waste treatment system 1 according to a second embodiment of the present disclosure. As shown in FIG. 2, the waste treatment system 1 further includes a heat-retaining steam pipe 8 that connects the reformer 2 and the microbial reaction device 3.

[0020] Exhaust steam S2 exhausted from the reformer 2 after the waste material is hydrolyzed in the reformer 2 flows through the heat-retention steam pipe 8. The reformer 2 supplies the exhaust steam S2 to the microbial reaction device 3 through this heat-retention steam pipe 8. The microbial reaction device 3 is kept warm by the heat of the exhaust steam S2 supplied from the reformer 2 so that the temperature is within a predetermined temperature range, for example, between 30°C and 50°C.

[0021] <Actions and Effects of the Waste Treatment System According to the Second Embodiment> It is desirable that the microbial reaction device 3 is kept warm within a predetermined temperature range in order to promote the decomposition of the reformate X1 by the microorganisms into smaller molecules. According to the second embodiment, the exhaust steam S2 is used as a heat source for keeping the microbial reaction device 3 warm. This makes it possible to suppress the amount of fuel prepared for keeping the microbial reaction device 3 warm, thereby reducing operating costs.

[0022] (Embodiment 3) Next, a waste treatment system 1 according to a third embodiment will be described. The waste treatment system 1 according to the third embodiment is obtained by adding a drying device 13 and a drying steam pipe 15 to the first embodiment. In the third embodiment, the same components as those in the first embodiment are given the same reference numerals, and detailed descriptions thereof will be omitted. The waste treatment system 1 according to another embodiment may be obtained by adding a drying device 13 and a drying steam pipe 15 to the second embodiment.

[0023] <Configuration of waste treatment system according to embodiment 3> Fig. 3 is a schematic diagram of a waste treatment system 1 according to a third embodiment of the present disclosure. As shown in Fig. 3, the waste treatment system 1 further includes a drying device 13 for drying a residue X2 obtained after the microbial reaction device 3 converts the reformed material X1 into smaller molecules using microorganisms, and a drying steam pipe 15 for connecting the reforming device 2 and the drying device 13.

[0024] 3, the waste treatment system 1 includes a dehydrator 14 that dehydrates a residue X2 (fermentation residue) that remains after the modified material X1 is decomposed into smaller molecules by the microorganisms in the microbial reaction device 3. The residue X2 dehydrated in the dehydrator 14 is supplied to the drying device 13.

[0025] Exhaust steam S2 exhausted from the reformer 2 after the waste material is hydrolyzed in the reformer 2 flows through the drying steam pipe 15. The reformer 2 supplies the exhaust steam S2 to the drying device 13 through the drying steam pipe 15. The drying device 13 dries the residue X2 dehydrated in the dehydrator 14 by using heat contained in the exhaust steam S2 supplied from the reformer 2.

[0026] <Actions and Effects of the Waste Treatment System According to the Third Embodiment> As illustrated in Fig. 3, the waste treatment system 1 including the microbial reaction device 3 may include a drying device 13 that dries the residue X2 obtained from the microbial reaction device 3. According to the third embodiment, the exhaust steam S2 is used as a heat source for the drying device 13 to dry the residue X2. Therefore, the amount of fuel prepared for drying the residue X2 in the drying device 13 can be suppressed, and the operating cost can be reduced.

[0027] (Embodiment 4) <Configuration of waste treatment system according to embodiment 4> Next, a waste treatment system 1 according to embodiment 4 will be described. The waste treatment system 1 according to embodiment 4 is obtained by adding a separation device 16 to embodiment 1. In embodiment 4, the same components as those in embodiment 1 are given the same reference symbols, and detailed descriptions thereof will be omitted. The waste treatment system 1 according to another embodiment may be obtained by adding a separation device 16 to embodiment 2 or 3.

[0028] 4 is a schematic diagram of a waste treatment system 1 according to a fourth embodiment of the present disclosure. As shown in FIG. 4, the waste treatment system 1 further includes a separation device 16 provided between the reformer 2 and the microbial reaction device 3.

[0029] The separator 16 separates unsuitable materials that are not suitable for generating biogas G1 in the microbial reaction device 3 from the reformed material X1, which is waste hydrolyzed in the reformer 2. Such a separator 16 separates the reformed material X1 into large particle components and small particle components smaller in particle size than the large particle components, and is, for example, a screen having an arbitrary mesh size, and the mesh size corresponds to the particle size of the boundary between the large particle components and the small particle components. The small particle components are depolymerized in the microbial reaction device 3 to generate valuable materials. The large particle components are separated from the reformed material X1 and are not supplied to the microbial reaction device 3. This is because the main components of the large particle components are components that have a relatively large particle size even after hydrolysis in the reformer 2, and cannot be depolymerized in the microbial reaction device 3, such as those derived from plastic waste and metals. In other words, the large particle components and the small particle components are unsuitable and suitable for reaction, respectively, for microbial reaction.

[0030] In the embodiment illustrated in FIG. 4, the waste treatment system 1 includes the above-mentioned dehydration device 14, a reformate transfer line 22 connecting the reformer 2 and the separation device 16, and a water injection pipe 24 connecting the dehydration device 14 and the reformate transfer line 22.

[0031] The reformed material transfer line 22 may be a pipe when the reformed material X1 is in a slurry state, or may be a conveyor or the like when the reformed material X1 is solid. Even if the reformed material X1 is solid, the reformed material transfer line 22 may be a pipe if it can be pumped by air or the like. The dehydrator 14 supplies water dehydrated from the residue X2 of the microbial reaction device 3 and boiler blow water to the reformed material X1 in the reformed material transfer line 22 through the water injection pipe 24. That is, the water injection pipe 24 is configured as a moisture adjustment device that adjusts the moisture content of the reformed material X1 between the reformer 2 and the microbial reaction device 3. In the embodiment illustrated in FIG. 5, the water injection pipe 24 adjusts the moisture content of the reformed material X1 upstream of the separation device 16, but the present disclosure is not limited to this embodiment. In another embodiment, the water injection pipe 24 adjusts the moisture content of the reformed material X1 downstream of the separation device 16.

[0032] 4, the waste treatment system 1 further includes a moisture amount acquisition device 30 that acquires the amount of moisture contained in the reformer 2. The moisture amount acquisition device 30 acquires the amount of moisture contained in the reformer 2 based on statistical data (including waste properties estimated by machine learning, AI, etc. based on an image) of the raw material supplied to the reformer 2, weight, compaction torque, reformer temperature (inside, surface), the amount of steam S1 supplied to the reformer 2, the duration of the state in which the steam S1 is supplied to the reformer 2, and the amount of temperature change in the reformer 2. That is, the moisture amount acquisition device 30 includes a flowmeter 30A that acquires the amount of steam S1 supplied to the reformer 2, a thermometer 30B that acquires the temperature in the reformer 2, a timer 30C, and a control device 30D. The control device 30D is electrically connected to each of the flow meter 30A, the thermometer 30B, and the timer 30C, and calculates (acquires) the amount of moisture contained in the reformer 2 based on the data acquired by each of the flow meter 30A, the thermometer 30B, and the timer 30C.

[0033] 4, as long as the moisture amount acquisition device 30 acquires the amount of moisture contained in the reformer 2. For example, the moisture amount acquisition device 30 may be a near-infrared type, a microwave type, or a capacitance type moisture meter.

[0034] The water injection pipe 24 (moisture adjustment device) adjusts the moisture content of the reformed product X1 based on the moisture content acquired by the moisture content acquisition device 30. In the embodiment illustrated in Fig. 4, the water injection pipe 24 is provided with an adjustment valve 32 for adjusting the amount of water (water dehydrated from the residue X2 in the microbial reaction device 3 and boiler blow water) supplied from the dehydration device 14 to the reformed product transfer line 22. The adjustment valve 32 is electrically connected to the control device 30D, and the opening degree is adjusted according to an instruction transmitted from the control device 30D.

[0035] In the embodiment illustrated in FIG. 4, the waste treatment system 1 includes a gas holder 18 that stores the biogas G1 generated in the microbial reaction device 3, a gas engine 20 that is driven using the biogas G1 stored in the gas holder 18 as fuel, an exhaust gas boiler 4A(4) that generates steam S1 using the heat of the exhaust gas G4 from the gas engine 20, and a combustion boiler 4B(4) that generates steam S1 using the biogas G1 stored in the gas holder 18 as fuel.

[0036] The biogas G1 stored in the gas holder 18 is supplied to the gas engine 20. The gas engine 20 is connected to a generator main body (power generation device) (not shown). The generator main body generates power using combustion energy generated by burning the biogas G1. At this time, the gas engine 20 emits exhaust gas G4.

[0037] Exhaust gas G4 discharged from the gas engine 20 is supplied to an exhaust gas boiler 4A. The exhaust gas boiler 4A (first steam generator) is for generating steam S1 to be supplied to the reformer 2. The exhaust gas boiler 4A generates steam S1 using only the combustion energy of the biogas G1, i.e., only the heat contained in the exhaust gas G4.

[0038] The biogas G1 stored in the gas holder 18 is also supplied to a combustion boiler 4B (second steam generating device). The combustion boiler 4B is for generating steam S1 to be supplied to the reformer 2. The combustion boiler 4B uses the biogas G1 as fuel and generates steam S1 using only the combustion energy of the biogas G1.

[0039] <Actions and Effects of the Waste Treatment System According to the Fourth Embodiment> According to the fourth embodiment, the separation device 16 is provided between the reformer 2 and the microbial reaction device 3, so that it is possible to reduce the amount of impurities supplied to the microbial reaction device 3. As a result, it is possible to reduce the risk that the production of the biogas G1 in the microbial reaction device 3 is inhibited, and the microbial reaction device 3 can efficiently produce the biogas G1.

[0040] Furthermore, according to the fourth embodiment, a water injection pipe 24 functioning as a moisture regulator is provided between the reformer 2 and the separator 16, so that the total solids concentration (TS) of the reformed material X1 hydrolyzed in the reformer 2 can be adjusted, and the efficiency of generating the biogas G1 by the microbial reaction device 3 can be improved. In addition, since the water obtained by dehydrating the residue X2 in the microbial reaction device 3 contains ammonia, when the nitrogen content in the reformed material X1 is low, a nitrogen-containing substance can be replenished to the reformed material X1.

[0041] According to the findings of the present inventors, it has been found that the amount of moisture contained in the reformer 2 can be obtained with high accuracy from the amount of steam S1 supplied to the reformer 2, the time during which the state in which the steam S1 is supplied to the reformer 2 continues, and the amount of temperature change in the reformer 2. According to the fourth embodiment, the waste treatment system 1 further includes a moisture amount acquiring device 30 that acquires the amount of moisture contained in the reformer 2, so that the amount of moisture contained in the reformer 2 can be acquired with high accuracy, and the efficiency of production of biogas G1 by the microbial reaction device 3 can be further improved.

[0042] According to the fourth embodiment, the total solid concentration (TS) of the reformed material X1 is adjusted based on the amount of moisture contained in the reformer 2 acquired by the moisture amount acquisition device 30 (calculated by the control device 30D), so that the efficiency of the production of biogas G1 by the microbial reaction device 3 can be further improved.

[0043] The exhaust gas boiler 4A and the combustion boiler 4B do not necessarily have to have the same capacity for generating steam S1. At least one of the exhaust gas boiler 4A and the combustion boiler 4B is configured to generate steam S1 according to the steam requirement of the reformer 2. The steam requirement of the reformer 2 is calculated based on, for example, the amount of waste input to the reformer 2 and the moisture content of the waste.

[0044] When the steam requirement of the reformer 2 can be met with the supply amount of steam S1 generated from one of the exhaust gas boiler 4A and the combustion boiler 4B, the other of the exhaust gas boiler 4A and the combustion boiler 4B can be put into a standby state or can generate steam other than that supplied to the reformer 2. Furthermore, when it is difficult to meet the steam requirement of the reformer 2 with only the supply amount of steam S1 generated from one of the exhaust gas boiler 4A and the combustion boiler 4B, the shortage can be made up for by the steam S1 generated by the other of the exhaust gas boiler 4A and the combustion boiler 4B. This allows for efficient operation of the waste treatment system 1.

[0045] Although the method of operating the exhaust gas boiler 4A and the combustion boiler 4B is not particularly limited, an example of the operating method will be described. The exhaust gas boiler 4A is always operated while the waste is hydrolyzed in the reformer 2. The combustion boiler 4B is not operated while the hydrolysis conditions in the reformer 2 can be adjusted only with the steam S1 generated in the exhaust gas boiler 4A. When adjusting the hydrolysis conditions according to the amount of waste input to the reformer 2 and the composition of the waste components, if the steam S1 generated in the exhaust gas boiler 4A alone is not enough, the combustion boiler 4B is operated to supply not only the steam S1 generated in the exhaust gas boiler 4A but also the steam S1 generated in the combustion boiler 4B to the reformer 2. In this way, the adjustment range of the hydrolysis conditions in the reformer 2 can be expanded compared to the case where only the exhaust gas boiler 4A is provided. Furthermore, by providing two or more gas engines 20 and operating the number of gas engines 20 according to the amount of steam S1 generated in the exhaust gas boiler 4A, the range of adjustment of the hydrolysis conditions in the reformer 2 can be further expanded.

[0046] (Embodiment 5) <Configuration of waste treatment system according to embodiment 5> Next, a waste treatment system 1 according to embodiment 5 will be described. The waste treatment system 1 according to embodiment 5 is limited to a case where a plurality of reforming devices 2 are provided, and in this respect it differs from the above-mentioned embodiments 1 to 4. In embodiment 5, the same components as those in embodiments 1 to 4 are given the same reference symbols, and detailed descriptions thereof will be omitted.

[0047] FIG. 5 is a schematic diagram of a waste treatment system 1 according to a fifth embodiment of the present disclosure. As shown in FIG. 5, the waste treatment system 1 includes a first reformer 2A(2) and a second reformer 2B(2). In the embodiment illustrated in FIG. 5, the first reformer 2A(2) and the second reformer 2B(2) are connected in parallel to each other, so that the input destination of the waste can be selected. The waste hydrolyzed in the first reformer 2A and the waste hydrolyzed in the second reformer 2B are supplied to the separator 16 through a common reformed product transfer line 22.

[0048] The first reformer 2A and the second reformer 2B hydrolyze the waste material with the steam S1 at different timings. For example, the timing at which the steam S1 is supplied to the first reformer 2A and the timing at which the steam S1 is supplied to the second reformer 2B are shifted from each other.

[0049] The number of reformers 2 provided in the waste treatment system 1 is not particularly limited, but when the reformer 2 is a batch-type reformer 2, the number of reformers 2 may be determined based on the batch time, which is the time from when waste is charged until the next waste is charged, and the temperature rise time, which is the time it takes to raise the temperature inside the reformer 2 to a preset temperature using steam S1. Specifically, the number of reformers 2 is determined by a natural number among values ​​obtained by dividing the batch time by the temperature rise time. With this configuration, changes in the amount of steam required from the reformer 2 can be efficiently suppressed.

[0050] <Actions and Effects of the Waste Treatment System According to the Fifth Embodiment> According to the fifth embodiment, the total steam requirement of the exhaust gas boiler 4A and the combustion boiler 4B can be reduced, and the amount of steam S1 supplied to the first reformer 2A and the second reformer 2B can be prevented from becoming insufficient, compared to the case where the first reformer 2A and the second reformer 2B perform hydrolysis at overlapping timings. In addition, since the total steam requirement of the exhaust gas boiler 4A and the combustion boiler 4B is reduced, the amount of biogas G1 used for generating steam S1 can be reduced. Therefore, the reduced amount of biogas G1 can be used for power generation in the gas engine 20, thereby increasing the amount of power generation.

[0051] Fig. 6 is a part of a schematic configuration diagram of a waste treatment system 1 according to an embodiment of the present disclosure, illustrating the peripheral configuration of the reformer 2. In one embodiment, as shown in Fig. 6, the waste treatment system 1 further includes an exhaust steam distribution pipe 26 that connects the first reformer 2A and the second reformer 2B.

[0052] In the embodiment illustrated in Fig. 6, the exhaust steam circulation pipe 26 includes a first exhaust steam circulation pipe 26A and a second exhaust steam circulation pipe 26B. The first exhaust steam circulation pipe 26A carries exhaust steam S21 (S2) exhausted from the first reformer 2A after the waste material is hydrolyzed in the first reformer 2A. The first reformer 2A supplies the exhaust steam S21 to the second reformer 2B via the first exhaust steam circulation pipe 26A. The second reformer 2B is heated by the heat of the exhaust steam S21 supplied from the first reformer 2A.

[0053] Similarly, the second exhaust steam distribution pipe 26B carries exhaust steam S22 (S2) exhausted from the second reformer 2B after the waste material is hydrolyzed in the second reformer 2B. The second reformer 2B supplies the exhaust steam S22 to the first reformer 2A via the second exhaust steam distribution pipe 26B. The first reformer 2A is heated by the heat of the exhaust steam S22 supplied from the second reformer 2B.

[0054] According to the configuration illustrated in FIG. 6, exhaust steam S2 generated after one reformer 2 hydrolyzes waste is used as a heat source for raising the temperature of the other reformer 2. This makes it possible to suppress the amount of fuel prepared for raising the temperature of the other reformer 2, thereby reducing operation costs. In the embodiment illustrated in FIG. 6, the exhaust steam circulation pipe 26 includes the first exhaust steam circulation pipe 26A and the second exhaust steam circulation pipe 26B, but the present disclosure is not limited to this embodiment. The exhaust steam circulation pipe 26 may be configured to allow both the exhaust steam S21 and the exhaust steam S22 to flow through it. In other words, the first reformer 2A and the second reformer 2B may be configured to be able to supply the exhaust steam S2 to each other through the common exhaust steam circulation pipe 26.

[0055] In one embodiment, assuming that the heating time required to heat the inside of the reformer 2 with the steam S1 to a preset temperature is Tr and the maintenance time required to maintain the temperature inside the reformer 2 at the preset temperature with the steam S1 is Tk, the relationship satisfies Tr / Tk≧0.3.

[0056] If the temperature rise time Tr is short, the temperature inside the reformer 2 is quickly raised to the set temperature, so the amount of steam required by the reformer 2 increases temporarily, which may make it difficult for the steam generator 4 to meet the requirements of the reformer 2. In contrast, since Tr / Tk≧0.3 is satisfied, the amount of steam required by the reformer 2 is prevented from increasing temporarily, and the steam generator 4 can meet the requirements of the reformer 2.

[0057] In another embodiment, Tr / Tk≧1.0 may be satisfied. According to this configuration, by making the temperature rise time Tr longer than the maintenance time Tk, it is possible to further suppress a temporary increase in the amount of steam required by the reformer 2, and to satisfy the requirement of the reformer 2.

[0058] Fig. 7A is a graph showing the relationship between time and the amount of steam S1 supplied to the first reformer 2A according to one embodiment. Fig. 7B is a graph showing the relationship between time and the amount of steam S1 supplied to the second reformer 2B according to one embodiment. In Figs. 7A and 7B, the horizontal axis shows time, and the vertical axis shows the amount of steam.

[0059] FIG. 7A will be described. t1 is the timing at which waste material starts being fed into the first reformer 2A. t2 is the timing at which steam S1 starts being fed into the first reformer 2A in order to raise the temperature inside the first reformer 2A to the set temperature. At the timing of t2, the feeding of waste material into the first reformer 2A is completed. t3 is the timing at which the feed of steam S1 into the first reformer 2A starts (the amount of feed is reduced) in order to maintain the temperature inside the first reformer 2A at the set temperature. t4 is the timing at which the steam S1 inside the first reformer 2A starts being exhausted to the outside. The hydrolysis of waste material in the first reformer 2A is mainly carried out between t2 and t4. t5 is the timing at which the exhaust of steam S1 inside the first reformer 2A ends. When the exhaust of steam S1 ends, the first reformer 2A goes into a standby state until the start of the next feeding of waste material (the second t1).

[0060] FIG. 7B will be described. t6 is the timing at which waste material starts being fed into the second reformer 2B. t7 is the timing at which steam S1 starts being fed into the second reformer 2B in order to raise the temperature inside the second reformer 2B to the set temperature. At the timing of t7, the feeding of waste material into the second reformer 2B is completed. t8 is the timing at which the feed of steam S1 starts (the amount of feed is reduced) into the second reformer 2B in order to maintain the temperature inside the second reformer 2B at the set temperature. t9 is the timing at which the steam S1 inside the second reformer 2B starts being exhausted to the outside. The hydrolysis of waste material in the second reformer 2B is mainly carried out between t7 and t9. t10 is the timing at which the exhaust of steam S1 inside the second reformer 2B ends. When the exhaust of steam S1 ends, the second reformer 2B is in a standby state until the start of the next feeding of waste material (the second t6).

[0061] From t2 to t3, the amount of steam supplied to the first reformer 2A gradually increases. This is to prevent the first reformer 2A from dissipating heat and to prevent a drop in the temperature inside the first reformer 2A by the amount of this heat dissipation. Similarly, from t7 to t8, the amount of steam supplied to the second reformer 2B gradually increases.

[0062] With reference to both FIG. 7A and FIG. 7B, steam operation of the waste treatment system 1 according to one embodiment will be described.

[0063] A1 is a first period during which the temperature in the first reformer 2A is increased to a preset temperature by the steam S1, and A2 is a second period during which the temperature in the second reformer 2B is increased to a preset temperature by the steam S1. That is, the first period A1 and the second period A2 correspond to the above-mentioned temperature increase time Tr. In one embodiment, as shown in FIG. 7A and FIG. 7B, the first reformer 2A is increased to a temperature by the steam S1, and the second reformer 2B is increased to a temperature by the steam S1 so that the first period A1 and the second period A2 do not overlap each other. With this configuration, the total steam requirement required for the exhaust gas boiler 4A and the combustion boiler 4B can be reduced compared to the case where the first period A1 and the second period A2 overlap each other.

[0064] Also, the third period during which the temperature in the first reformer 2A is maintained at the set temperature by the steam S1 is designated as A3, and the fourth period during which the temperature in the second reformer 2B is maintained at the set temperature by the steam S1 is designated as A4. That is, the third period A3 and the fourth period A4 correspond to the above-mentioned maintenance time Tk. In one embodiment, the first reformer 2A is maintained at the set temperature by the steam S1, and the second reformer 2B is heated by the steam S1 so that the third period A3 is included in the second period A2. The amount of steam S1 for maintaining the reformer 2 at the set temperature is much smaller than the amount of steam S1 for heating the reformer 2 to the set temperature. That is, even if steam operation is performed to maintain the first reformer 2A at the set temperature while the second reformer 2B is being heated, there is little possibility that the steam S1 supplied to the second reformer 2B will be insufficient. For this reason, the operation time of the first reformer 2A and the second reformer 2B can be increased. In addition, in another embodiment, the first reformer 2A may be heated with steam S1 and the second reformer 2B may be maintained at a set temperature with steam S1 so that the fourth period A4 is included within the next first period A1.

[0065] Fig. 8 is a flow chart of a waste treatment method 50 according to an embodiment of the present disclosure. As shown in Fig. 8, the waste treatment method 50 includes a step 52 of hydrolyzing waste with steam S1, a step 54 of converting a reformate X1 containing at least solids from the waste hydrolyzed with the steam S1 into smaller molecules using microorganisms, and a step 56 of generating steam S1 using only the combustion energy of the biogas G1 generated in the step 54 of converting the reformate X1 into smaller molecules using microorganisms. According to this method, the demand for steam S1 for hydrolyzing the waste can be quickly met.

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

[0067] [1] A waste treatment system (1) according to the present disclosure includes at least one reformer (2) that hydrolyzes waste with steam (S1), a microbial reactor (3) that converts the reformate (X1) containing at least solids from the waste hydrolyzed in the at least one reformer into smaller molecules using microorganisms, and at least one steam generator (4) that generates the steam using only the combustion energy of gas produced in the microbial reactor.

[0068] Gaseous fuels burn faster than solid or liquid fuels. According to the configuration described in [1] above, the reformer hydrolyzes the gas produced in the microbial reactor using only the combustion energy of the gas. This allows the reformer to quickly meet the demand for steam.

[0069] [2] In some embodiments, the configuration described in [1] above further includes an insulation steam pipe (8) connecting the reformer and the microbial reaction device, and the reformer supplies exhaust steam (S2) obtained after hydrolysis of the waste to the microbial reaction device via the insulation steam pipe, and the microbial reaction device is kept warm by the heat of the exhaust steam supplied from the reformer so that it is within a predetermined temperature range.

[0070] It is desirable that the microbial reactor is kept warm within a predetermined temperature range in order to promote the breakdown of the reformed material by the microorganisms into smaller molecules. According to the configuration described in [2] above, the exhaust steam after the reformer hydrolyzes the waste is used as a heat source for keeping the microbial reactor warm. This makes it possible to reduce the amount of fuel prepared for keeping the microbial reactor warm, thereby reducing operating costs.

[0071] [3] In some embodiments, the configuration described in [1] or [2] above further includes a drying device (13) that dries a residue (X2) obtained after the microbial reaction device converts the reformed material into smaller molecules by microorganisms, and a drying steam pipe (15) that connects the reformer and the drying device, and the reformer supplies exhaust steam after hydrolysis of the waste to the drying device via the drying steam pipe, and the drying device dries the residue with heat contained in the exhaust steam supplied from the reformer.

[0072] The waste treatment system may include a drying device that dries the residue obtained from the microbial reaction device. According to the configuration described in [4] above, the exhaust steam after the reformer hydrolyzes the waste is used as a heat source for the drying device to dry the residue. This reduces the amount of fuel that the drying device needs to prepare to dry the residue, thereby reducing operating costs.

[0073] [4] In some embodiments, the configuration according to any one of [1] to [3] above further comprises a separator (16) disposed between the at least one reformer and the microbial reactor, the separator separating unsuitable materials from the waste hydrolyzed in the at least one reformer that are not suitable for producing the gas in the microbial reactor.

[0074] According to the configuration described in [4] above, the amount of impurities supplied to the microbial reaction device can be reduced. As a result, the risk of gas production being inhibited in the microbial reaction device is reduced, and the microbial reaction device can efficiently produce gas.

[0075] [5] In some embodiments, in the configuration described in any one of [1] to [4] above, the at least one steam generating device includes a first steam generating device (4A) and a second steam generating device (4B), and is configured to generate the steam from at least one of the first steam generating device and the second steam generating device in response to a steam requirement of the reformer.

[0076] According to the configuration described in [5] above, when one of the first steam generating device and the second steam generating device can satisfy the steam requirement of the reformer, the other steam generating device can be put into a standby state or can generate steam other than that supplied to the reformer. Also, when it is difficult to satisfy the steam requirement of the reformer with only one steam generating device, the shortage can be made up for by the steam generated by the other steam generating device. This makes it possible to realize an efficient operation of the waste treatment system.

[0077] [6] In some embodiments, in the configuration described in any one of [1] to [5] above, the at least one reformer includes a plurality of reformers, and at least two of the plurality of reformers are configured to perform hydrolysis at different times from each other.

[0078] According to the configuration described in [6] above, the total amount of steam required from the steam generator can be reduced, and the amount of steam supplied to the reformers can be prevented from being insufficient, compared to when at least two of the multiple reformers perform hydrolysis at overlapping times. In addition, each of the multiple reformers is supplied with steam generated using only the combustion energy of gas, not steam obtained by burning solid or liquid fuel. Therefore, the steam request from the reformers can be met quickly.

[0079] [7] In some embodiments, in the configuration described in [6] above, the plurality of reformers include a first reformer (2A) and a second reformer (2B), and further include an exhaust steam circulation pipe (26) connecting the first reformer and the second reformer, and exhaust steam after hydrolysis of the waste is supplied from the first reformer to the second reformer via the exhaust steam circulation pipe, and the second reformer is heated by heat of the exhaust steam supplied from the first reformer.

[0080] According to the configuration described in [7] above, the exhaust steam from one reformer after hydrolyzing the waste is used as a heat source to heat the other reformer, which reduces the amount of fuel required to heat the other reformer and reduces operating costs.

[0081] [8] In some embodiments, in the configuration described in any one of [1] to [7] above, when a heating time for raising the temperature in the reformer to a preset temperature using the steam is Tr and a maintenance time for maintaining the temperature in the reformer at the preset temperature using the steam is Tk, Tr / Tk≧0.3 is satisfied.

[0082] If the temperature rise time is short, the temperature inside the reformer is quickly raised to the set temperature, so the amount of steam required by the reformer increases temporarily, which may make it difficult to meet the requirements of the reformer. In contrast, the configuration described in [8] above satisfies Tr / Tk≧0.3, so that the amount of steam required by the reformer is suppressed from increasing temporarily, and the requirements of the reformer can be met.

[0083] [9] In some embodiments, in the configuration described in [8] above, Tr / Tk≧1.0 is satisfied.

[0084] According to the configuration described in [9] above, by making the temperature rise time Tr longer than the maintenance time Tk, it is possible to further suppress a temporary increase in the amount of steam required by the reformer, and to meet the requirements of the reformer.

[0085]

[10] In some embodiments, the configuration according to any one of [1] to [9] above further comprises a moisture adjustment device (24) between the at least one reformer and the microbial reactor for adjusting the moisture content of the waste hydrolyzed in the at least one reformer.

[0086] According to the configuration described in

[10] above, the total solids concentration (TS) of the waste hydrolyzed in the reformer can be adjusted, so that the efficiency of gas production by the microbial reactor can be improved.

[0087]

[11] In some embodiments, the configuration described in

[10] above further includes a moisture content acquisition device (30) that acquires the amount of moisture contained in the reformer, and the moisture adjustment device adjusts the moisture content of the waste hydrolyzed in the at least one reformer based on the moisture content acquired by the moisture content acquisition device.

[0088] According to the configuration described in

[11] above, the total solids concentration (TS) of the waste hydrolyzed in the reformer is adjusted based on the amount of moisture contained in the reformer, thereby further improving the efficiency of gas production by the microbial reactor.

[0089]

[12] In some embodiments, in the configuration described in

[11] above, the moisture content acquisition device acquires the amount of moisture contained in the reformer based on the amount of steam supplied to the reformer, the time during which the steam is supplied to the reformer, and the amount of temperature change within the reformer.

[0090] According to the findings of the present inventors, it has been found that the amount of moisture contained in the reformer can be obtained with high accuracy from the amount of steam supplied to the reformer, the time during which the state in which steam is supplied to the reformer continues, and the amount of temperature change in the reformer. According to the configuration described in

[12] above, the amount of moisture contained in the reformer can be obtained with high accuracy, and the efficiency of gas production by the microbial reaction device can be further improved.

[0091]

[13] A waste treatment method (50) according to the present disclosure includes a step (52) of hydrolyzing waste with steam, a step (54) of converting the hydrolyzed waste, which contains at least solids, into smaller molecules using microorganisms, and a step (56) of generating the steam using only the combustion energy of the gas produced in the step of converting the hydrolyzed waste into smaller molecules using microorganisms.

[0092] The method described in

[13] above allows the steam demand for waste hydrolysis to be met quickly. [Explanation of symbols]

[0093] 1 Waste treatment system 2. Reformer 2A 1st reformer 2B Second reformer 3. Microbial Reactor 4. Steam Generator 4A Exhaust gas boiler (first steam generator) 4B Combustion boiler (second steam generator) 8. Steam piping for heat retention 13 Drying equipment 15 Drying steam piping 16 Separation device 24 Water injection pipe (moisture adjustment device) 26 Exhaust steam distribution piping 30 Moisture content acquisition device 50 Waste disposal methods A1 1st Period A2 2nd period A3 3rd Period A4 4th Period S1 Steam S2 Exhaust steam X1 modified product X2 residue

Claims

1. at least one reformer for hydrolyzing the waste material with steam; a microbial reaction device that uses microorganisms to convert the modified product containing at least solids from the waste hydrolyzed in the at least one reforming device into smaller molecules; a moisture amount acquiring device for acquiring the amount of moisture contained in the reformer; At least one steam generating device that generates the steam using only the combustion energy of the gas generated in the microbial reaction device, the at least one steam generating device being configured to generate the steam in response to a steam requirement of the at least one reformer calculated based on the moisture content acquired by the moisture content acquisition device; and a moisture adjusting device provided between the at least one reforming device and the microbial reaction device, for adjusting the moisture content of the waste hydrolyzed in the at least one reforming device based on the moisture content acquired by the moisture content acquiring device. Waste disposal system.

2. Further comprising a heat-insulating steam pipe connecting the reformer and the microbial reaction device; Exhaust steam after hydrolysis of the waste is supplied from the reformer to the microbial reaction device via the heat-retaining steam piping; The microbial reaction device is kept warm by the heat of the exhaust steam supplied from the reformer so that it is within a predetermined temperature range.

2. The waste treatment system according to claim 1.

3. a drying device that dries a residue obtained after the microbial reaction device converts the modified substance into smaller molecules by microorganisms; A drying steam pipe connecting the reformer and the drying device, The exhaust steam after hydrolysis of the waste is supplied from the reformer to the dryer through the drying steam pipe; The drying device dries the residue by heat of the exhaust steam supplied from the reformer.

3. A waste treatment system according to claim 1 or 2.

4. The method further comprises a separation device disposed between the at least one reformer and the microbial reactor; The separator separates unsuitable materials from the waste hydrolyzed in the at least one reformer that are unsuitable for producing the gas in the microbial reactor. A waste treatment system according to any one of claims 1 to 3.

5. the at least one steam generating unit includes a first steam generating unit and a second steam generating unit; configured to generate the steam from at least one of the first steam generating device and the second steam generating device in response to a steam demand of the reformer. A waste treatment system according to any one of claims 1 to 4.

6. the at least one reformer comprises a plurality of reformers; At least two of the plurality of reformers are configured to perform hydrolysis at different times from each other. A waste treatment system according to any one of claims 1 to 5.

7. the plurality of reformers includes a first reformer and a second reformer, further comprising an exhaust steam distribution pipe connecting the first reformer and the second reformer; The exhaust steam obtained after hydrolyzing the waste material is supplied from the first reformer to the second reformer via the exhaust steam distribution pipe; The second reformer is heated by the heat of the exhaust steam supplied from the first reformer.

7. A waste treatment system according to claim 6.

8. where Tr is a temperature rise time during which the temperature in the reformer is raised to a preset temperature by the steam, and Tk is a maintenance time during which the temperature in the reformer is maintained at the preset temperature by the steam, and Tr / Tk≧0.3 is satisfied. A waste treatment system according to any one of claims 1 to 7.

9. Tr / Tk≧1.0 is satisfied; 9. The waste treatment system according to claim 8.

10. the moisture amount acquisition device acquires the amount of moisture contained in the reformer based on the amount of the steam supplied to the reformer, the time during which the state in which the steam is supplied to the reformer continues, and the amount of change in the state in the reformer.

2. The waste treatment system according to claim 1.

11. hydrolyzing the waste material in a reformer with steam; Obtaining the amount of water contained in the reformer; A step of converting the hydrolyzed waste into smaller molecules using microorganisms. generating the steam according to a steam requirement of the reformer calculated based on the amount of water contained in the reformer, using only combustion energy of the gas generated in the step of converting the reformate into smaller molecules by microorganisms; and adjusting the moisture content of the waste hydrolyzed in the reforming device based on the obtained moisture content. Waste disposal methods.

12. at least one reformer for hydrolyzing the waste material with steam; a microbial reaction device that uses microorganisms to convert the modified product containing at least solids from the waste hydrolyzed in the at least one reforming device into smaller molecules; At least one steam generating device that generates the steam using only the combustion energy of the gas produced in the microbial reactor; a moisture amount acquiring device for acquiring the amount of moisture contained in the reformer; a moisture adjusting device provided between the at least one reforming device and the microbial reaction device, which adjusts the moisture content of the waste hydrolyzed in the at least one reforming device based on the moisture content acquired by the moisture content acquiring device; a dehydration device that dehydrates the residue remaining after the microbial reaction device decomposes the modified substance into smaller molecules by microorganisms; A reformed product line communicating with the reformer and the microbial reaction device, the reformed product line having a flow path formed therein through which the reformed product flows; The moisture adjustment device includes a water injection pipe communicating between the dehydration device and the reformate line. Waste disposal system.

13. The moisture adjusting device further includes a regulating valve provided in the water injection pipe, The regulating valve is configured to adjust an opening degree based on the moisture content acquired by the moisture content acquisition device.

13. A waste treatment system according to claim 12.

14. the moisture amount acquisition device acquires the amount of moisture contained in the reformer based on the amount of the steam supplied to the reformer, the time during which the state in which the steam is supplied to the reformer continues, and the amount of change in the state in the reformer.

14. A waste treatment system according to claim 12 or 13.

15. hydrolyzing the waste material in a reformer with steam; A step of converting the hydrolyzed waste into smaller molecules by microorganisms in a microbial reactor, the modified product including at least solids being hydrolyzed; Obtaining the amount of water contained in the reformer; adjusting the moisture content of the waste hydrolyzed in the reformer based on the obtained moisture content in the reformer; A step of dehydrating the residue remaining after the modified material is decomposed into smaller molecules by microorganisms; and generating the steam using only the combustion energy of the gas generated in the step of decomposing the reformed product into smaller molecules by microorganisms; The moisture content of the waste is adjusted by supplying water generated by dehydrating the residue to the modified material in a modified material line that communicates with the modified device and the microbial reaction device. Waste disposal methods.

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