JP2019042692A - Biological treatment device and methane gas manufacturing method - Google Patents

Abstract

To miniaturize a device.SOLUTION: A biological treatment device 100 comprises a crushing part 110 for crushing organic solid waste so as to become 0.5 mm-10 mm, a first reaction tank 310 forming a solid introduction port 320a and a first treatment liquid discharge port 312 provided above the solid introduction port 320a and storing a suspension of including an anaerobic microorganism group of including any one or a plurality of hydrolysis fungi, acid fermentation fungi and methane fermentation fungi and the crushed solid waste and a soluble reactor 130 having a plurality of first inclined plates 332 inclined to a horizontal surface, provided between the solid introduction port 320a and the first treatment liquid discharge port 312 in the first reaction tank 310 and limiting the movement to the first treatment liquid discharge port 312 of the solid waste.SELECTED DRAWING: Figure 1

Description

  The present disclosure relates to a biological treatment apparatus and a method for producing methane gas.

  Conventionally, organic solid wastes (hereinafter simply referred to as “solid wastes”) such as sewage sludge, agricultural wastes, livestock wastes, fishery wastes, food wastes and raw garbage discarded from home are dried Were disposed of by landfill after being reduced in volume by being incinerated. However, dioxin may be generated when incinerating solid waste. For this reason, volume reduction techniques to replace incineration, such as methane fermentation treatment, have been developed. The methane fermentation treatment includes a reaction of solubilizing solid waste, a reaction of acid-fermenting the solubilized treated liquid, and a reaction of methane-fermenting the acid-fermented liquid to be treated. There are cases where these reactions are carried out in one tank, and cases in which each reaction is carried out in separate tanks and carried out in series.

  When each reaction is carried out in one tank (for example, Patent Document 1), the microbial reaction is carried out in the presence of solid waste, and the remaining solid waste is discharged at a certain rate, but the microorganism is also discharged at the same time. Therefore, the concentration of microorganisms in the tank can not be increased, and the processing speed per volume does not increase, resulting in an increase in the size of the apparatus.

  On the other hand, as technology to perform the above-mentioned methane fermentation processing by the method of dividing each reaction into another tank and performing it in series, an apparatus equipped with a raw garbage dissolution tank, an acid generation tank, a precipitation tank and a methane fermentation tank was developed (For example, Non-Patent Document 1). The garbage disposal tank stirs the garbage (solid waste) with water to solubilize it with aerobic microorganisms. The acid generation tank stirs and acid-ferrates the solubilization solution in which raw garbage with a particle size of less than 1 mm is suspended, which is generated in the raw garbage dissolution tank. The settling vessel settles solids from the suspension produced by the acid generation vessel. The methane fermenter is a reactor of EGSB (Expanded Granular Sludge Bed) type, in which granules of methane fermentation bacteria are accommodated. The methane fermenter decomposes the organic matter in the liquid to be treated from which the solid matter has been removed by the settling tank into methane gas by granules. In this case, since solid waste does not flow into the methane fermentation tank, the methane fermentation tank can be miniaturized.

Patent No. 3135284 gazette

Sakamoto, K. et al., Two-phase methane fermentation characteristics of garbage using aerobic solubilization process Journal of the Waste Society Society, Vol. 16, No. 5, pp. 369-377 (2005)

  However, the methane fermentation processing technology as described in Non-Patent Document 1 requires a raw garbage dissolving tank dedicated to solubilization, an acid generating tank dedicated to acid fermentation, and a settling tank, resulting in an increase in the overall size of the apparatus. There is.

  Then, this indication aims at provision of the biological treatment apparatus which can miniaturize an apparatus in view of such a subject, and a methane gas manufacturing method.

  In order to solve the above problems, a biological treatment apparatus according to an aspect of the present disclosure includes a crushing unit that crushes organic solid waste into 0.5 mm or more and 10 mm or less, a solid inlet, and A first treatment liquid outlet provided above the solid substance inlet is formed, and an anaerobic microorganism group comprising any one or more of a hydrolyzing bacterium, an acid-fermenting bacterium, and a methane-fermenting bacterium, A first reaction tank containing a suspension containing the crushed solid waste, and a first reaction liquid outlet provided between the solid substance inlet and the first processing liquid outlet in the first reaction tank, And D. a solubilization reactor having a plurality of first inclined plates inclined with respect to a horizontal surface, which restricts the movement of solid waste to the first treatment liquid outlet.

  Moreover, it may be provided in the downward direction of the said solid substance inlet in the said 1st reaction tank, and you may provide the aeration part which supplies gas in a said 1st reaction tank.

  The aeration unit may supply the biogas exhausted from the first reaction tank.

  Also, a storage tank for storing a first processing liquid discharged from the first processing liquid outlet, and a circulation pump for circulating the first processing liquid stored in the storage tank to the first reaction tank, You may have.

  Moreover, you may provide the pH adjustment part which adjusts pH of the suspension accommodated in a said 1st reaction tank to predetermined value of 5 or more and less than 7.

  In addition, a nutrient salt supply unit may be provided to supply a nutrient salt of the anaerobic microorganism group to the first reaction tank.

  Further, a treatment liquid inlet through which the first treatment liquid discharged from the first treatment liquid outlet is introduced, and a second treatment liquid outlet provided above the treatment liquid inlet are formed. An anaerobic microorganism group, and a second reaction tank containing the first treatment liquid, and the treatment liquid inlet and the second treatment liquid outlet in the second reaction tank, the anaerobic A methane fermentation reactor having a plurality of second inclined plates inclined with respect to a horizontal surface, which restricts the movement of the anaerobic microorganism group to the second treatment liquid outlet, and the anaerobic microorganism group from the second reaction tank And a delivery unit for taking out and delivering to the first reaction vessel.

  In order to solve the above-mentioned subject, the methane gas manufacturing method concerning one mode of this indication is a process of crushing organic solid waste so that it may be 0.5 mm or more and 10 mm or less, a solid inlet, and A first treatment liquid outlet provided above the solid substance inlet, and an anaerobic microorganism group comprising any one or more of a hydrolyzing bacterium, an acid-fermenting bacterium, and a methane-fermenting bacterium; A first reaction vessel containing a suspension containing the crushed solid waste, and the solid treatment inlet and the first treatment liquid outlet in the first reaction vessel, the solid The solid reaction inlet of the solubilization reactor having a plurality of first inclined plates inclined with respect to a horizontal surface, which restricts the movement of waste to the first treatment liquid outlet, into the first reaction tank through the solid substance inlet. Work to introduce crushed solid waste And, including the.

  According to the present disclosure, it is possible to miniaturize the device.

It is a figure explaining a biological treatment apparatus. It is a flow chart explaining a flow of processing of a methane gas production method.

  Hereinafter, an embodiment of the present disclosure will be described in detail with reference to the attached drawings. The dimensions, materials, and other specific numerical values and the like shown in this embodiment are merely examples for facilitating understanding and do not limit the present disclosure unless otherwise specified. In the specification and the drawings, elements having substantially the same functions and configurations will be denoted by the same reference numerals to omit repeated descriptions, and elements not directly related to the present disclosure will not be illustrated. Do.

(Biological treatment apparatus 100)
FIG. 1 is a diagram for explaining a biological treatment apparatus 100. In FIG. 1, the flow of substances such as solid waste, liquid, gas and the like is indicated by solid arrows, and the flow of signals is indicated by dashed arrows.

  As shown in FIG. 1, the biological treatment apparatus 100 includes a crushing unit 110, a solid introduction unit 120, a solubilization reactor 130, an aeration unit 140, a storage tank 150, a circulation pump 160, and a pH adjustment unit. 170, a nutrient salt supply unit 180, a first processing solution introduction unit 190, a methane fermentation reactor 200, and a delivery unit 210.

  The crushing unit 110 crushes the organic solid waste into 0.5 mm or more and 10 mm or less (the length and the major diameter of the largest portion). Solid wastes are wastes derived from organisms (animals and plants and microorganisms). The solid wastes are, for example, sewage sludge, agricultural wastes, livestock wastes, fish wastes, food wastes, raw wastes discarded from homes, and the like. The solid waste may be attached with anaerobic microorganisms including hydrolysing bacteria and acid-fermenting bacteria.

  The solid introduction unit 120 introduces the solid waste crushed by the crushing unit 110 into the solubilization reactor 130 (first reaction tank 310) described later. The solid introduction unit 120 includes, for example, a hopper 122 and a screw feeder 124. The hopper 122 is formed in a substantially conical shape whose internal space gradually decreases from the upper side to the lower side, and stores the solid waste crushed by the crushing unit 110. The screw feeder 124 delivers the solid waste stored in the hopper 122 to the solubilization reactor 130. The solid introduction unit 120 delivers solid waste in an amount such that most of the solid waste is solubilized and acid-fermented in the solubilization reactor 130. The solid introduction unit 120, for example, intermittently introduces solid waste into the solubilization reactor 130.

  The solubilization reactor 130 is a so-called UASB (Upflow Anaerobic Sludge Blanket) type device. As shown in FIG. 1, the solubilization reactor 130 includes a first reaction vessel 310, an introduction pipe 320, a settler 330, and a first gas discharge pipe 340.

  The first reaction vessel 310 is a hollow container (for example, a square cylinder). The first reaction vessel 310 contains a suspension containing solid waste and anaerobic microorganisms. In the first reaction tank 310, the solubilization reactor 130 adheres to solid waste, or propagates in the first reaction tank 310, or solid waste is discarded by anaerobic microorganisms delivered from the methane fermentation reactor 200 described later. Solubilize and acidify. Specifically, among the anaerobic microorganisms, hydrolyzing bacteria hydrolyze and solubilize the organic matter in the solid waste. In addition, among anaerobic microorganisms, acid-fermenting bacteria acid-ferment the solubilized organic matter. Therefore, in the first reaction tank 310, a liquid (first processing liquid) containing an organic substance (organic acid) and a biogas mainly containing carbon dioxide are generated.

  The introduction pipe 320 is a pipe in which a part is disposed in the first reaction tank 310 and the other part is connected to the outlet of the screw feeder 124. A plurality of solid material inlets 320 a are formed in a part of the introduction pipe 320. The solid inlet 320a faces upward. The other end of the introduction pipe 320 is connected to the screw feeder 124. Therefore, solid waste and the first treatment liquid are introduced into the first reaction tank 310 from the screw feeder 124 through the introduction pipe 320 (solids inlet 320 a). The first treatment liquid is introduced from the storage tank 150 described later to the screw feeder 124 via the circulation pipe 162 and the hopper 122.

  As described above, when organic matter in the solid waste is solubilized and acid-fermented by the hydrolyzing bacteria and the acid-fermenting bacteria in the first reaction tank 310, biogas is produced. Also, biogas is introduced from the aeration tube 146 described later. These biogases may rise up as they are or may adhere to solid waste and rise up with the solid waste.

  The settler 330 is installed inside the first reaction vessel 310. The settler 330 is disposed above the introduction pipe 320 (solids inlet 320 a) and below the first treatment liquid outlet 312 of the first reaction tank 310. The settler 330 is composed of a plurality of first inclined plates 332 having a structure capable of collecting floating gas. The first inclined plate 332 has an open lower surface and a closed upper surface (inverted funnel shape, hemispherical shape, gable roof shape, etc.).

  The gas (biogas) collected by the settler 330 is sent to the biogas tank 142 through the first gas discharge pipe 340.

  By providing the settler 330, the biogas adheres, and the floated solid waste can collide with the first inclined plate 332 to separate the biogas from the solid waste. Among the solid wastes from which the biogas has been removed, those which do not rise by the movement of the first treatment liquid (hereinafter referred to as "large solid wastes") fall under their own weight. That is, the settler 330 (the first inclined plate 332) restricts the movement of the solid waste to the first treatment liquid outlet 312. Therefore, it can be avoided that large solid waste is discharged out of the first reaction tank 310 together with the first treatment liquid.

  A plurality of first inclined plates 332 may be provided and arranged in a row at a predetermined interval horizontally. In addition, when the first inclined plate 332 is formed in multiple stages in the vertical direction and viewed from above, the first inclined plate 332 of the upper inclined plate row covers the gap between the first inclined plates 332 of the lower inclined plate row. You may Thereby, the solid waste surfaced with the gas can be made to collide with any one of the first inclined plates 332.

  On the other hand, the solid waste may become so small as to be solubilized and continue to be acid-fermented, and may become so small as to rise with the movement of the first treatment liquid. Solid waste (hereinafter referred to as “small solid waste”) small enough to rise with the movement of the first treatment liquid is a fraction (estimated about 5%) of the solid waste introduced. is there. For this reason, even if small solid waste is introduced into the methane fermentation reactor 200 of the latter UASB method, the problem is extremely reduced compared to the case where the solid waste crushed by the crushing unit 110 is directly introduced. Furthermore, as will be described later, a part of the small solid waste can settle in the storage tank 150 and can be discharged from the drain pipe 156.

  The liquid from which the biogas has been collected and removed by the settler 330 overflows through the first processing liquid outlet 312 formed at the top of the first reaction tank 310 as the first processing liquid.

  The aeration unit 140 includes a biogas tank 142, a blower 144, and an air diffuser 146. The biogas tank 142 stores the biogas exhausted from the first reaction tank 310. The blower 144 feeds the biogas stored in the biogas tank 142 to the aeration pipe 146. The aeration tube 146 is provided in the first reaction vessel 310 to supply the biogas to the first reaction vessel 310.

  The storage tank 150 stores the first treatment liquid discharged from the first reaction tank 310. A partition plate 152 is provided in the storage tank 150. The partition plate 152 is connected to one side surface of the storage tank 150 and the side surface opposite to the side surface, and extends from above the liquid surface to below the liquid surface. The lower end of the partition plate 152 is separated from the bottom surface of the storage tank 150. Moreover, the stirrer 154 is provided in one area | region divided by the partition plate 152 in the storage tank 150. As shown in FIG.

  The circulation pump 160 circulates the first treatment liquid to the first reaction tank 310. Circulation pump 160 is provided in circulation pipe 162. The circulation pipe 162 connects one region of the storage tank 150 (a region provided with the stirrer 154) and the hopper 122. The circulation pipe 162 delivers the first treatment liquid stored in the storage tank 150 to the first reaction tank 310. As described above, the storage tank 150 stores the first processing liquid discharged from the first reaction tank 310. Therefore, the circulation pump 160 circulates the first treatment liquid to the first reaction tank 310 through the hopper 122 and the screw feeder 124. Thereby, the solid waste adhering to the hopper 122 can be washed away with the first treatment liquid.

  In the first reaction tank 310, residues of solid wastes that could not be solubilized in the long run accumulate. For this reason, the residue is suspended in the first treatment liquid and flows out. Since the stirrer 154 is not provided in the other region of the storage tank 150, part of the solid waste that has flowed out of the first reaction tank 310 may be precipitated in the other region. The precipitate is drained and disposed appropriately by opening the drain valve 158.

  The pH adjusting unit 170 adjusts the pH of the suspension contained in the first reaction tank 310 to a predetermined value (e.g., 6) of 5 or more and less than 7. The pH adjustment unit 170 includes, for example, a pH meter 172, an alkali tank 174, and a pump 176. The pH meter 172 measures the pH of one region of the reservoir 150. The alkali tank 174 stores an alkali solution. The pump 176 supplies the alkaline solution stored in the alkaline tank 174 to one area of the reservoir 150 so that the pH measured by the pH meter 172 becomes a predetermined value of 5 or more and less than 7. For example, the pump 176 starts supply of the alkaline solution when the pH measured by the pH meter 172 reaches 5.5. Thus, the pH of the first treatment liquid stored in the storage tank 150 can be maintained at 5 or more and less than 7. Therefore, the pH of the first treatment liquid delivered to the first reaction tank 310 by the circulation pump 160 is also 5 or more and less than 7, and the pH of the suspension contained in the first reaction tank 310 is 5 or more and less than 7 It will be maintained at the value of

  In the first reaction tank 310, when the acid fermentation of the solid waste proceeds by the acid-fermenting bacteria, the pH of the suspension decreases. Then, the activities of the hydrolyzing bacteria and the acid-fermenting bacteria are reduced. Therefore, as described above, the pH adjusting unit 170 adjusts the pH of the suspension contained in the first reaction tank 310 to a predetermined value of 5 or more and less than 7. Thereby, in the first reaction tank 310, the situation in which the activities of the hydrolyzing bacteria and the acid-fermenting bacteria decrease can be avoided. Therefore, it becomes possible to efficiently perform solubilization and acid fermentation of solid waste in the first reaction tank 310. In addition, when the pH of the suspension contained in the first reaction tank 310 is adjusted to less than 6, the activity of methane fermentation bacteria can be suppressed.

  The nutrient salt supply unit 180 supplies the nutrient salt to the first reaction tank 310. The nutrient salt supply unit 180 includes, for example, a nutrient salt tank 182 and a pump 184. The nutrient salt tank 182 stores nutrients of hydrolyzing bacteria and acid fermenting bacteria among the anaerobic microorganisms. The pump 184 supplies the nutrient stored in the nutrient tank 182 to one area of the reservoir 150. Then, nutrient salts are supplied to the first reaction tank 310 by the circulation pump 160. By the structure provided with the nutrient salt supply part 180, in the 1st reaction tank 310, it becomes possible to maintain the activity of a hydrolysing microbe and an acid fermenting microbe.

  The first treatment liquid introducing unit 190 introduces the first treatment liquid stored in the storage tank 150 into the methane fermentation reactor 200. The first treatment liquid introducing unit 190 includes, for example, an introducing pipe 192 and an introducing pump 194. The introduction pipe 192 connects the other region of the storage tank 150 (the region where the stirrer 154 is not provided) and the second reaction tank 410 (treatment liquid inlet 412) of the methane fermentation reactor 200. The introduction pump 194 is provided in the introduction pipe 192.

  The methane fermentation reactor 200 is a so-called UASB (Upflow Anaerobic Sludge Blanket) type device. The methane fermentation reactor 200 has substantially the same configuration as the solubilization reactor 130 except that it has no aeration part. Specifically, the methane fermentation reactor 200 includes a second reaction tank 410, a settler 430, and a second gas discharge pipe 440.

  The second reaction vessel 410 is a hollow vessel (for example, a square cylinder). The 2nd reaction tank 410 accommodates the 1st processing liquid and methane fermentation bacteria. The methane fermentation reactor 200 converts the organic substance contained in the first treatment liquid into methane gas in the second reaction tank 410 by methane fermentation bacteria. Then, a liquid (second processing liquid) from which the organic matter is decomposed and removed is generated, and a biogas mainly composed of methane gas is generated. The generated biogas is stored in a methane gas tank 202. The generated second treatment liquid is discharged to the latter treatment equipment.

  Before starting the operation of the biological treatment apparatus 100, the second reaction tank 410 contains granules of methane-fermenting bacteria. Granules are massive particles mainly composed of methane-fermenting bacteria. Since the granules have a size and mass density which do not rise by the movement of the culture solution (the first treatment solution, the second treatment solution), they settle in the lower part of the second reaction tank 410. For this reason, in the lower part of the second reaction vessel 410, a granular layer composed of granules is formed.

  The first treatment liquid is introduced into the second reaction tank 410 through the introduction pipe 192 and the treatment liquid inlet 412 formed in the second reaction tank 410.

  The first treatment solution introduced from the treatment solution inlet 412 rises through the granular layer, and finally, the second treatment solution discharged above the treatment solution inlet 412 in the second reaction tank 410 is discharged. The exit 414 is reached. As described above, the methane fermenting bacteria convert the organic matter in the first treatment liquid into methane gas. Therefore, in the process in which the first treatment solution introduced from the treatment solution inlet 412 passes through the granular layer, the organic matter in the first treatment solution is converted to methane gas.

  Thus, the second treatment liquid from which the organic matter is decomposed into methane gas and removed is discharged from the second treatment liquid outlet 414.

  The settler 430 is installed inside the second reaction vessel 410. The settler 430 is disposed above the treatment liquid inlet 412 and below the second treatment liquid outlet 414. The settler 430 is composed of a plurality of second inclined plates 432 having a structure capable of collecting the rising biogas (methane gas). Similar to the first inclined plate 332, the second inclined plate 432 has a shape (inverted funnel shape, hemispherical shape, gable roof shape, etc.) with the upper surface closed by opening the lower surface.

  The gas collected by the settler 430 is sent to the methane gas tank 202 through the second gas discharge pipe 440.

  By providing the settler 430, the biogas adheres, and the floated granules can collide with the second inclined plate 432 to separate the biogas from the granules. The granules from which the biogas has been removed fall to the granule layer by their own weight. That is, the settler 430 (second inclined plate 432) restricts the movement of the granule to the second treatment liquid outlet 414. Therefore, it can be avoided that the granules are discharged out of the second reaction tank 410 together with the second treatment liquid.

  A plurality of second inclined plates 432 may be provided and arranged in a row at a predetermined interval horizontally. In addition, when the second inclined plate 432 is formed in multiple stages in the vertical direction and viewed from above, the second inclined plate 432 of the upper inclined plate row covers the gap between the second inclined plates 432 of the lower inclined plate row. You may This allows the granules that have surfaced with the gas to collide with any of the second inclined plates 432.

  The second processing liquid discharged from the second processing liquid discharge port 414 is returned to the other region of the storage tank 150 (a region not provided with a stirrer). A part of the second treatment liquid returned to the storage tank 150 may overflow from the other region (effluent). In addition, the other second treatment liquid returned to the other region of the storage tank 150 is introduced together with the first treatment liquid flowing in through the gap between the lower end of the partition plate 152 and the bottom surface of the storage tank 150. It may be introduced into the second reaction tank 410 through the pipe 192.

  The delivery unit 210 takes out the second treatment liquid containing the anaerobic microorganism group from the second reaction tank 410 and delivers it to the first reaction tank 310. The delivery unit 210 includes, for example, a delivery pipe 212 and a pump 214. One end of the delivery pipe 212 is connected to the second reaction tank 410, and the opening at the other end faces the hopper 122. The pump 214 is provided on the delivery pipe 212. Therefore, when the pump 214 is driven, the second treatment liquid containing the anaerobic microorganisms stored in the second reaction tank 410 is delivered to the hopper 122. Thereby, the anaerobic microorganisms are delivered to the first reaction tank 310. Thereby, the concentration of the anaerobic microorganism group in the first reaction tank 310 (in particular, the concentration of the hydrolyzing bacteria and the acid-fermenting bacteria) can be increased. Therefore, it becomes possible to promote the solubilization and acid fermentation of the solid waste in the first reaction tank 310.

  As described above, solid waste of 0.5 mm or more and 10 mm or less is introduced into the solubilization reactor 130 of the present embodiment. The solid waste of 0.5 mm or more and 10 mm or less exhibits the same behavior as granules in the first reaction vessel 310. That is, solid waste does not accompany the first treatment liquid flowing upward as it does not adhere to the gas. Therefore, the residence time of the solid waste in the first reaction tank 310 can be extended. This makes it possible to sufficiently perform solubilization and acid fermentation of solid waste.

  In addition, since the solubilization and the acid fermentation can be performed only by the solubilization reactor 130, the biological treatment apparatus 100 can be downsized as compared with the conventional technology provided with an apparatus dedicated to solubilization and an apparatus dedicated to acid fermentation. It is possible to

(Methane gas production method)
Then, the methane gas manufacturing method using the biological treatment apparatus 100 is demonstrated. FIG. 2 is a flowchart for explaining the process flow of the methane gas production method. As shown in FIG. 2, the methane gas production method includes a crushing step S510, a first introduction step S520, a solubilization / acid fermentation step S530, a second introduction step S540, and a methane fermentation step S550.

(Crushing process S510)
The crushing step S510 is a step of crushing the solid waste into 0.5 mm or more and 10 mm or less.

(First introduction step S520)
The first introduction step S520 is a step of introducing the solid waste, in which the solid introduction portion 120 is crushed, into the solubilization reactor 130.

(Solubilization / acid fermentation process S530)
In the solubilization / acid fermentation step S530, in the solubilization reactor 130, the step of solubilizing the organic matter of the solid waste with hydrolyzing bacteria, and acid-ferring the solubilized organic matter with acid fermentation bacteria to produce a first treatment liquid It is.

(2nd introduction process S540)
The second introduction step S540 is a step in which the first treatment liquid introduction unit 190 introduces the first treatment liquid into the methane fermentation reactor 200.

(Methane fermentation process S550)
The methane fermentation step S550 is a step of the methane fermentation bacteria in the methane fermentation reactor 200 decomposing the organic substance in the first treatment liquid into methane gas to produce methane gas.

  As described above, according to the methane production method of the present embodiment, solubilization and acid fermentation can be performed in parallel, and therefore, the conventional technology provided with a device dedicated to solubilization and a device dedicated to acid fermentation In comparison to the above, the biological treatment apparatus 100 can be miniaturized.

  As mentioned above, although one embodiment was described, referring to an accompanying drawing, it goes without saying that this indication is not limited to the above-mentioned embodiment. It is apparent that those skilled in the art can conceive of various modifications and alterations within the scope of the claims, and it is understood that they are naturally within the technical scope of the present disclosure. Be done.

  For example, in the embodiment described above, the case where the methane fermentation reactor 200 is a UASB reactor has been described as an example. However, the methane fermentation reactor 200 may be a reactor such as a CSTR (stirred tank), a fixed bed, a fluidized bed, or a method similar to the UASB method. Also, the solubilization reactor 130 has been described by way of example of a configuration in which one settler 330 is provided. However, the solubilization reactor 130 may be provided with two settlers in the vertical direction.

  Moreover, in the said embodiment, the structure which crushes solid waste into 0.5 mm or more and 10 mm or less is mentioned as an example, and the crushing part 110 mentioned and demonstrated it. However, the crushing unit 110 may crush the solid waste so as not to rise in size as the first processing liquid moves.

  In the above embodiment, the configuration in which the aeration unit 140 reintroduces the biogas exhausted from the first reaction tank 310 into the first reaction tank 310 has been described as an example. This configuration makes it possible to rock the solid waste at low cost. However, as long as the aeration unit 140 can swing the solid waste in the first reaction tank 310 and the oxygen content is low to such an extent that the activity of the anaerobic microorganism group is not reduced, the type of gas is not limited. The aeration unit 140 may supply, for example, a combustion exhaust gas or a gas requiring deodorization to the first reaction tank 310.

  Moreover, in the said embodiment, the biological treatment apparatus 100 provided the storage tank 150 and the circulation pump 160, and mentioned as an example the structure which circulates a 1st process liquid to the 1st reaction tank 310, and demonstrated it. However, the storage tank 150 and the circulation pump 160 are not essential components. For example, fresh culture fluid may be continuously supplied to the first reaction tank 310. In this case, as long as the pH of the first treatment liquid (culture fluid) in the first reaction tank 310 is constantly maintained at 5 or more and less than 7, the pH adjustment unit 170 may be omitted.

  Moreover, in the said embodiment, the biological treatment apparatus 100 mentioned and demonstrated the structure provided with the nutrient salt supply part 180 to an example. However, when the solid waste contains a nutrient salt of an anaerobic microorganism, the nutrient salt supply unit 180 may be omitted.

  Moreover, in the said embodiment, the structure which the pH adjustment part 170 supplies the alkaline solution to the storage tank 150 was mentioned as the example, and was demonstrated. However, as long as the pH adjustment unit 170 can maintain the pH in the first reaction tank 310 at 5 or more and less than 7, the supply position of the alkaline solution is not limited. For example, the pH adjusting unit 170 may supply the alkaline solution to the hopper 122 or the first reaction tank 310.

  Moreover, in the said embodiment, the structure which supplies the nutrient salt to the storage tank 150 was mentioned as an example, and the nutrient salt supply part 180 demonstrated it. However, the nutrient salt supply unit 180 may supply nutrient salts to the first reaction tank 310. For example, the nutrient salt supply unit 180 may supply the nutrient salt to the hopper 122 or the first reaction tank 310.

  Moreover, in the said embodiment, the biological treatment apparatus 100 mentioned and demonstrated the structure provided with the sending part 210 to an example. However, the sending unit 210 is not an essential component.

  The present disclosure can be applied to a biological treatment apparatus and a methane gas production method.

DESCRIPTION OF SYMBOLS 100 Biological treatment apparatus 110 Crushing part 130 Solubilization reactor 140 Aeration part 150 Storage tank 160 Circulation pump 170 pH adjustment part 180 Nutrient supply part 200 Methane fermentation reactor 210 Delivery part 310 1st reaction tank 312 1st processing liquid outlet 320a Solids inlet 332 first inclined plate 410 second reaction tank 412 treatment liquid inlet 414 second treatment liquid outlet 432 second inclined plate

Claims (8)

Crusher that crushes organic solid waste into 0.5 mm or more and 10 mm or less,
A solid inlet and a first treatment liquid outlet provided above the solid inlet are formed, and any one or more of a hydrolytic bacterium, an acid fermenter, and a methane fermenter are formed. And a first reaction tank containing a suspension containing the crushed solid waste, the solid material inlet in the first reaction tank, and the first treatment liquid outlet. A solubilization reactor having a plurality of first inclined plates inclined with respect to a horizontal surface, provided between the plurality of first plates for limiting movement of the solid waste to the first treatment solution outlet;
A biological treatment apparatus comprising:   The biological treatment apparatus according to claim 1, further comprising: an aeration unit provided below the solid substance inlet in the first reaction tank and supplying a gas into the first reaction tank.   The biological treatment apparatus according to claim 2, wherein the aeration unit supplies the biogas exhausted from the first reaction tank. A storage tank storing the first processing liquid discharged from the first processing liquid outlet;
A circulation pump for circulating the first treatment liquid stored in the storage tank to the first reaction tank;
The biological treatment apparatus according to any one of claims 1 to 3, comprising:   The biological treatment apparatus according to any one of claims 1 to 4, further comprising a pH adjustment unit configured to adjust the pH of the suspension contained in the first reaction tank to a predetermined value of 5 or more and less than 7.   The biological treatment apparatus according to any one of claims 1 to 5, further comprising a nutrient salt supply unit configured to supply a nutrient salt of the anaerobic microorganism group to the first reaction tank. A treatment liquid inlet through which the first treatment liquid discharged from the first treatment liquid outlet is introduced, and a second treatment liquid outlet provided above the treatment liquid inlet are formed, and the anaerobic A microorganism group and a second reaction vessel containing the first treatment solution, and the anaerobic microorganism provided between the treatment solution inlet and the second treatment solution outlet in the second reaction vessel A methane fermentation reactor having a plurality of second inclined plates inclined with respect to a horizontal surface, which restricts movement of the group to the second treatment liquid outlet;
A delivery unit for taking out the anaerobic microorganism group from the second reaction vessel and delivering it to the first reaction vessel;
The biological treatment apparatus according to any one of claims 1 to 6, comprising Crushing organic solid waste into 0.5 mm or more and 10 mm or less,
A solid inlet and a first treatment liquid outlet provided above the solid inlet are formed, and any one or more of a hydrolytic bacterium, an acid fermenter, and a methane fermenter are formed. And a first reaction tank containing a suspension containing the crushed solid waste, the solid material inlet in the first reaction tank, and the first treatment liquid outlet. Through the solids inlet of the solubilization reactor having a plurality of first inclined plates inclined with respect to the horizontal plane, which are disposed between the first and second treatment stages to limit the movement of the solid waste to the first treatment solution outlet. Introducing the crushed solid waste into the first reaction vessel;
A method for producing methane gas comprising

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