JP7453855B2 - Fermentation equipment, method for using fermentation equipment, and method for producing methane gas - Google Patents

Description

TECHNICAL FIELD The present invention relates to a fermentation apparatus and a method for producing methane gas using food waste or the like as a fermentation raw material.

As one of the measures to effectively utilize food waste, it has been proposed to generate methane gas by anaerobic digestion (methane gas fermentation) and collect and use the methane gas.
That is, raw materials such as garbage are fermented by anaerobic bacteria to generate methane gas, which is used for power generation, etc.
Food waste, etc. is crushed into small pieces beforehand and then put into the fermentation tank. Wet crushing equipment is often used to crush food waste and the like.

Japanese Patent Application Publication No. 2018-26301

Wet type crushing equipment is a device that crushes objects in liquid, and can crush objects more finely than dry type crushing equipment.
In the conventional technology, clean water such as tap water or underground water is injected into a wet crushing device along with food waste, etc., and the rotary blades etc. are driven while the chamber of the wet crushing device is filled with water. Crush food waste, etc.

In the conventional fermentation apparatus, as described above, clean water and the like were injected into the wet crushing apparatus. Therefore, there was a problem that the consumption of clean water and the like was large.
The present invention focuses on the above-mentioned problems of the prior art and aims to propose a fermentation apparatus and a method for producing methane gas that can suppress the consumption of clean water such as tap water.

A mode for solving the above-mentioned problems includes a crushing process section for crushing fermentation raw materials and a fermentation tank, the fermentation raw materials crushed in the crushing process section are introduced into the fermentation tank, and the fermentation raw materials are fermented in the fermentation tank. The fermentation apparatus for fermenting raw materials is characterized in that it has a reflux conveyance path for returning moisture in the fermenter to the crushing process section.

Here, "moisture" means "containing water". What is returned to the crushing process section via the reflux conveyance path contains digestive fluid. In this embodiment, water required during crushing is supplemented by using water from digestive juices. In many cases, what is returned to the crushing process section through the reflux conveyance path is a slurry in which solids and water are mixed.
The "conveyance path" may be a conduit made of steel pipes, hoses, etc., or may be a conveyor capable of conveying objects containing moisture, such as a screw conveyor or a bucket conveyor.
According to this aspect, the water in the fermenter is supplied to the crushing process section, so the usage fees for clean water and the like can be reduced.
In some cases, the chamber of the crusher can be filled with liquid without using clean water or the like.

In the above aspect, the temperature-controlled circulation conveyance path has a heat exchange section in the middle thereof, and the temperature-controlled circulation conveyance path takes out moisture in the fermenter and removes moisture from the heat exchange section. The pump is equipped with a pump, the suction side of which is connected to the fermenter, the discharge side of the pump is branched, and one of the branches is connected to the heat exchanger. It is preferable that the temperature-controlled circulation conveyance path is configured by connecting to one of the branches, and the reflux conveyance path is configured by another one of the branches.

The fermentation apparatus of this embodiment has a temperature-controlled circulation conveyance path. The temperature-controlled circulation conveyance path circulates the contents of the fermenter via a heat exchanger.
In the fermentation apparatus of this embodiment, the temperature of the contents can be adjusted by the heat exchanger in the temperature-controlled circulation conveyance path, so that the fermentation raw material in the fermenter can be maintained at a temperature suitable for fermentation.
Further, in the fermentation apparatus of this embodiment, the pump for the temperature-controlled circulation conveyance path and the pump for the reflux conveyance path are shared, so the number of parts is small.

In each of the above embodiments, it is desirable to have a human waste storage tank for storing animal excrement and urine, and a human waste supply conveyance path for sending the human waste stored in the human waste storage tank to the crushing process section.

"Animals" include cows, horses, pigs, sheep and other mammals, and birds such as chickens. The term "animal" also includes humans.
Human waste contains a lot of water.
In the fermentation apparatus of this embodiment, the human waste is supplied to the crushing process section, and the moisture in the human waste is used to slurry the fermentation raw material, so that the amount of clean water and the like used can be reduced.

In each of the above aspects, the crushing process section has a rough crushing device and a wet crushing device, and the wet crushing device is arranged downstream of the rough crushing device, and It is desirable that the fermentation raw material is further crushed in the wet crushing device.

According to this aspect, food waste and the like are crushed by the coarse crusher, and further finely crushed by the wet crusher.
In the fermentation device of this embodiment, the fermentation raw material crushed in the rough crushing device is sent to the wet crushing device. Therefore, fermentation raw materials are likely to be caught in the wet crushing equipment.
That is, if the fermented raw material is large, it may float in the wet crushing device and be difficult to get caught up in the blades of the wet crushing device.
In the fermentation apparatus of this embodiment, the fermentation raw material crushed by the coarse crusher is sent to the wet crusher, so the fermentation raw material is easily caught in the wet crusher and is finely crushed by the wet crusher.
According to this aspect, the fermentation raw material is transported to the fermentation tank in a finely pulverized state, so that fermentation can easily proceed.

In the above aspect, the crushing process section includes the rough crushing device and the wet crushing device arranged above and below each other, and the two are connected directly or through a pipe, It is desirable that a water level sensor is provided between a rough crushing device-side breaking section where the fermentation raw material is broken in the crushing device and a wet-side breaking section where the fermentation material is broken in the wet crushing device.

In the fermentation apparatus of this embodiment, since the water level sensor is provided between the wet-side breaking section where the fermentation raw material is broken, it is possible to accurately detect whether there is enough liquid in the wet-side breaking section. can.

In each of the above embodiments, a storage tank for temporarily storing fermentation raw materials is provided, a first input conveyance path connecting the crushing process section and the fermenter, and a stockpiling conveyance connecting the crushing process section and the storage tank. It is desirable to have a second input conveyance path connecting the storage tank and the fermentation tank.

Here, the "storage tank" may be a tank with an open upper space, such as a pool, or a closed tank, such as a tank.
The fermentation apparatus of this embodiment includes a storage tank for temporarily storing fermentation raw materials. Therefore, when there is a large amount of fermentation raw material transported from the outside to the fermentation apparatus, the fermentation raw material can be crushed and stored in the storage tank via the stockpiling conveyance path.
Further, if necessary, it can be transported from the storage tank to the fermentation tank via the second input conveyance path.

In the above aspect, the conveyance path switching means is provided, and a total amount of the fermentation raw material crushed in the crushing process section is transported into the fermentation tank, and a part of the fermentation raw material crushed in the crushing process part is transferred to the fermentation tank. A partial charge of carrying the fermentation raw material into the fermentation tank and the remaining part into the storage tank, and an addition of carrying the fermentation raw material in the storage tank into the fermentation tank at the same time in addition to the entire amount of the fermentation raw material crushed in the crushing process section. It is desirable that it be possible to implement the input.

According to this aspect, even if there are variations in the amount of fermentation raw materials introduced into the fermentation apparatus and the amount of collected garbage, etc., the amount of fermentation raw materials input into the fermentation tank can be equalized.

An aspect of the method using the fermentation apparatus of the above aspect is that the amount of crushed fermentation raw materials per a certain time being crushed in the crushing process section is larger than the scheduled amount of fermentation raw materials to be input into the fermenter per a certain time. If the fermentation raw material is crushed in the crushing process section, a part of the fermentation raw material crushed in the crushing process section is carried into the fermentation tank, and the rest is carried into the storage tank. If the amount of crushed per certain period of time is less than the scheduled amount of fermentation raw materials input per certain time into the fermenter, the total amount of fermented raw materials crushed in the crushing process section, plus the amount of fermentation raw material in the storage tank The method is characterized in that additional input is carried out in which raw materials are simultaneously carried into the fermenter.

A "certain period of time" is a relatively long span, such as one hour, three hours, or half a day.
According to this aspect, even if there is variation in the amount of fermentation raw materials introduced into the fermentation apparatus, the amount of fermentation raw materials introduced into the fermenter can be equalized.

Another aspect for solving the same problem is to include a slurry-forming process in which fermentation raw materials containing food waste are crushed and made into a slurry, and a fermentation raw material slurried in the slurry-forming process to be introduced into a fermentation tank. A method for producing methane gas comprising a fermentation step of fermenting methane to obtain methane gas and digestive fluid, characterized in that during the slurrying step, the digestive fluid obtained in the fermenter is added to the fermentation raw material and crushed. It is.

The fermentation apparatus and methane gas production method of the present invention have the effect of suppressing consumption of clean water and the like.

FIG. 1 is a system diagram of a fermentation apparatus according to an embodiment of the present invention. FIG. 2 is an enlarged view of the vicinity of the crushing process section of the fermentation apparatus of FIG. 1. FIG. 2 is an enlarged view of the vicinity of the human waste tank of the fermentation apparatus of FIG. 1. FIG. FIG. 2 is an enlarged view of the vicinity of the storage tank of the fermentation apparatus shown in FIG. 1. FIG. FIG. 2 is a system diagram of the fermentation apparatus of FIG. 1, showing the flow of fermentation raw materials and digestive fluid when the entire amount of fermentation raw materials is introduced into a fermenter. FIG. 2 is a system diagram of the fermentation apparatus of FIG. 1, showing the flow of fermentation raw materials when a portion of the fermentation raw materials are introduced into a fermentation tank. FIG. 2 is a system diagram of the fermentation apparatus of FIG. 1, showing the flow of fermentation raw materials when the entire amount of crushed fermentation raw materials is carried into a storage tank. FIG. 2 is a system diagram of the fermentation apparatus of FIG. 1, showing the flow of fermentation raw materials when additionally charging the fermentation raw materials to the fermenter. FIG. 2 is a system diagram of the fermentation apparatus of FIG. 1, showing the flow of fermentation raw materials when controlling the temperature of the fermentation raw materials in the fermenter. FIG. 2 is a block diagram of a control device of the fermentation apparatus of FIG. 1. FIG.

Embodiments of the present invention will be further described below.
The fermentation apparatus 1 of this embodiment uses food waste or human waste as a fermentation raw material, crushes the raw material, charges it into a fermenter 2, and performs methane fermentation to obtain methane gas.
The fermentation apparatus 1 of this embodiment can be divided into a fermentation tank 2 and a fermentation fuel supply section 3, as shown in FIG.
The fermentation fuel supply section 3 includes a crushing process section 10, a human waste storage tank 11, and a storage tank 12.

Each part will be explained below.
Fermenter 2 is a closed tank. Inside the fermenter 2, there is a stirring device 17.
The fermenter 2 is equipped with a liquid level gauge, a temperature sensor, a pressure sensor, etc. (none of which are shown), similar to known devices.
Furthermore, the fermentation tank 2 has a large number of openings (not shown), which function as an input port for fermentation raw materials and a take-out port for taking out fermentation raw materials.

The fermenter 2 is provided with a temperature-controlled circulation conveyance path 20 as shown in FIGS. 1 and 9.
The temperature-controlled circulation conveyance path 20 is a pipe that connects a raw material extraction hole 21 provided in the fermenter 2 and a raw material return hole 22, and a circulation pump 25 and a secondary side of a heat exchanger 26 are interposed in the intermediate portion. has been done.
The primary side of the heat exchanger 26 is connected to a water heater (not shown).
Further, a flow path adjustment valve 23 is interposed in the temperature control circulation conveyance path 20 . The opening degree of the flow path regulating valve 23 can be adjusted by a motor, and can also be completely closed.

The fermentation tank 2 is a tank in which food waste and human waste are put into the fermentation tank 2, and are subjected to methane fermentation by the action of anaerobic bacteria to generate methane gas (anaerobic digestion method).
Digestive juices are also produced as a byproduct of fermentation.

Next, the crushing process section 10 will be explained.
As shown in FIG. 2, the crushing process section 10 has a crushing section 15 comprised of two crushing devices.
In this embodiment, the crushing section 15 includes a dry crushing device 30 and a wet crushing device 31.
Although the type and blade structure of the dry crushing device 30 are not limited, a two-shaft dry crushing device is employed in this embodiment. Moreover, the dry crushing device 30 functions as a rough crushing device.
The wet crushing device 31 is also not limited in its type or blade structure, but in this embodiment, one in which a rotary blade is provided in a chamber is used.
The wet crushing device 31 is arranged downstream of the dry crushing device 30.

As shown in FIG. 2, the crushing process section 10 of this embodiment has a dry crushing device 30 and a wet crushing device 31 stacked one above the other in a vertically stacked positional relationship, and both are directly connected.
That is, the dry crushing device 30 has an input port and a discharge port, and the discharge port of the dry crushing device 30 is directly connected to the input port of the wet crushing device 31. Note that the two may be connected by a tubular member.
The dry crushing device 30 and the wet crushing device 31 are connected to prevent water from leaking.

In this embodiment, a water level sensor 33 is provided between the dry crushing device 30 and the wet crushing device 31.
The water level sensor 33 is located between the rough crushing device side breaking section 27 of the dry crushing device 30 where the fermentation raw material is broken and the wet side breaking section 28 of the wet crushing device 31 where the fermentation raw material is broken.
The part where the fermentation raw material is broken is, for example, a part where the blades and the liner come into contact with each other in a single-shaft crusher, and a part where the blades engage with each other in the case of a two-shaft crusher.

Other members constituting the crushing process section 10 include an input conveyor 35, a discharge conveyor 36, and a first pressure pump 37.
The input conveyor 35 is a known bucket conveyor or belt conveyor, and is used to convey food waste brought in by a truck or the like to the input port of the dry crushing device 30.
The discharge conveyor 36 is, for example, a screw conveyor, and feeds the fermentation raw material in the form of slurry to the first pressure pump 37 .
The first pressure pump 37 is a mixing pump.

Next, the human waste storage tank 11 will be explained.
The human waste storage tank 11 is a hermetically sealed tank, and has a human waste inlet 38 and human waste discharge parts 72 and 73.

Next, the storage tank 12 will be explained.
The storage tank 12 includes an introduction tank 40 and a main storage section 41. The introduction tank 40 is a small tank.
The main storage section 41 is a large tank. The introduction tank 40 and the main storage section 41 are both pool-like tanks with open tops.
A pull-up conveyor 42 is provided between the introduction tank 40 and the main storage section 41.
Further, a screen 43 is provided at the most downstream portion of the pull-up conveyor 42.
The main storage section 41 is provided with a stirrer 45 .

A garbage crusher 47 and an introduction conveyor 46 are installed in the storage tank 12 as accessory members. The introduction conveyor 46 is a screw conveyor.

Next, the connection between each member will be explained with reference to FIG. 1.
In addition to the illustrated piping members, each pipe is provided with a strainer, an on-off valve, a check valve, etc. (not illustrated).
First, we will explain the line that transports food waste (more precisely, a slurry made by crushing food waste and mixing it with water).
In the fermentation apparatus 1 of this embodiment, the crushing process section 10 and the fermenter 2 are connected by a first input conveyance path 50.
Specifically, the first input conveyance path 50 is a conduit that connects the discharge side of the first pressure pump 37 of the crushing process section 10 and the upper side of the fermenter 2 with piping.

The first input conveyance path 50 has a branch part 76 in the middle, and a branch pipe 75 is connected thereto. The branch pipe 75 is open above the storage tank 12 .
In this implementation, a part of the first input conveyance path 50 and the branch pipe 75 constitute a stockpiling conveyance path 78 that connects the crushing process section 10 and the storage tank 12, as shown in FIG.
The branch pipe 75, which is a part of the stockpiling conveyance path 78, may be connected to the side surface or bottom of the storage tank 12. The stockpiling conveyance path 78 may be independent from the first input conveyance path 50.

An on-off valve 51 is provided on the downstream side (fermentation tank 2 side) of the branch portion 76 of the first input conveyance path 50. Further, the branch pipe 75 is also provided with an on-off valve 53. The two on-off valves 51 and 53 function as a conveyance path switching means 57.
The on-off valves 51 and 53 are used to switch the destination of the fermentation raw material and change the division ratio of the slurry.

The storage tank 12 and the fermentation tank 2 are connected by a second input conveyance path 55. A second pressure pump 56 is provided in the second input conveyance path 55 .

Next, the reflux conveyance path 60 that returns the fermentation raw material containing moisture from the fermenter 2 side to the crushing process section 10 side will be explained. The fermentation apparatus 1 of this embodiment uses the digestive fluid in the fermenter 2, and the "fermented raw materials containing moisture" returned from the fermenter 2 to the crushing process section 10 also includes undigested fermented raw materials. Although it contains a large amount of water, for the sake of simplicity, the "fermented raw material containing water" returned from the fermenter 2 to the crushing process section 10 will be referred to as "digestive fluid."

The fermentation apparatus 1 of this embodiment has the temperature-controlled circulation conveyance path 20 as described above. The downstream side of the circulation pump 25 of the temperature-controlled circulation conveyance path 20 is branched to form a reflux conveyance path 60 that reaches the crushing process section 10 side. In this embodiment, the reflux conveyance path 60 partially overlaps with the temperature-controlled circulation conveyance path 20, and the same circulation pump 25 sends the digestive fluid.
In the fermentation apparatus 1 of this embodiment, the number of parts is small because the pipes and the pump are shared.
A flow path adjustment valve 67 is interposed in the reflux conveyance path 60 . The opening degree of the flow path regulating valve 67 can be adjusted by a motor, and it can also be completely closed.

The end of the reflux conveyance path 60 is branched into branch pipes 60c and 60d, as shown in FIGS. 1 and 2, and connected to the crushing section 15 and the first pressure pump 37. An on-off valve 87 is provided in the branch pipe 60d leading to the first pressure pump 37.
The branch pipe 60c is further branched into branch paths 60a and 60b, and connected to the dry crushing device 30 and wet crushing device 31 of the crushing section 15. An on-off valve 86 is provided in the branch pipe 60a leading to the dry crushing device 30.
As described above, the crushing section 15 is one in which the dry crushing device 30 and the wet crushing device 31 are connected, and the end of the reflux conveyance path 60 is connected to the dry crushing device 30 and the wet crushing device 31 as shown in FIGS. It is connected to both sides of the device 31 (branch paths 60a, 60b).

By opening the on-off valve 86 and branching a part of the digestive fluid sent through the circulation conveyance path 60 to the branch path 60a, the digestive fluid is introduced into the dry crushing device 30, and the hopper and blades of the dry crushing device 30 are The remaining food waste can be flushed away.

Next, piping related to the human waste storage tank 11 will be explained.
In this embodiment, one human waste discharge section 72 is connected to the confluence section 71 of the reflux conveyance path 60 by the human waste introduction path 62.
In this embodiment, the human waste storage tank 11 is connected to the crushing process section 10 by a human waste introduction path 62 and a reflux conveyance path 60. In this embodiment, the human waste introduction path 62 and the reflux transport path 60 constitute a human waste supply and transport path 68 .
The human waste supply conveyance path 68 may be a flow path independent from the reflux conveyance path 60.
A human waste feed pump 63 is provided in the human waste introduction path 62. An on-off valve 65 is provided at a junction 71 with the reflux conveyance path 60 and at a position on the fermenter 2 side. Further, an on-off valve 66 is also provided in the human waste introduction path 62. The on-off valves 65 and 66 function as a switching means 81.
Further, a communication pipe 77 is connected to the other human waste discharge part 73 of the human waste storage tank 11, and the communication pipe 77 is open to the upper part of the introduction tank 40 of the storage tank 12. The communication pipe 77 is provided with an on-off valve 83. The connecting pipe 77 may be connected to the side or bottom of the storage tank 12.

Next, the water supply circuit 85 will be explained.
In the fermentation apparatus 1 of this embodiment, clean water can be supplied to the introduction tank 40 and main storage section 41 of the storage tank.
Moreover, clean water can also be supplied to the crushing section 15.

The fermentation apparatus 1 of this embodiment has a control device 70 that controls the entire fermentation apparatus.
As shown in FIG. 10, the control device 70 has a temperature control section and a return flow rate control section.
The temperature control unit detects the temperature inside the fermenter 2 with a temperature sensor (not shown), and controls the temperature inside the fermenter 2 by feeding it back to the water heater (not shown) and the flow path adjustment valve 23. It fulfills the function of
The return flow rate control section controls the amount of digestive fluid returned from the fermenter 2 based on the signal from the water level sensor 33.

Next, the flow of fermentation raw materials and the like in the fermentation apparatus 1 will be explained.
The fermentation apparatus 1 of this embodiment uses food waste and livestock human waste as fermentation raw materials to ferment methane gas in a fermentation tank 2 to obtain methane gas.
Food waste, which serves as a raw material, is collected in urban areas and transported to the fermentation device 1 by trucks A and B.
Livestock human waste is provided by farmers, transported by a vacuum car C, and collected in a human waste storage tank 11. Human excrement and urine may also be used.

Food waste is normally collected on the crushing process section 10 side, and is input to the crushing section 15 by the input conveyor 35 and crushed (crushed process).
At this time, the circulation pump 25 is driven, and all the on-off valves (65, 67) provided between the fermenter 2 and the crushing process section 10 in the reflux conveyance path 60 are opened.
As a result, as shown by the thick line in FIG. 5, the digestive fluid in the fermenter 2 is supplied to the crushing process section 10 side.

In the crushing section 15, the digestive fluid returned from the fermenter 2 and the newly introduced garbage are crushed and mixed.
That is, the newly input garbage is roughly crushed by the dry crushing device 30 in the upper part, and sent to the wet crushing device 31 on the downstream side together with the digestive fluid returned from the fermenter 2.
The chamber of the wet crushing device 31 is filled with digestive fluid and food waste, and the food waste is crushed into small pieces in the liquid. Furthermore, the garbage stirred by a rotary blade or the like is mixed with digestive fluid and turned into a slurry.
Clean water is supplied to the crushing unit 15 as needed, but in the fermentation apparatus 1 of the present embodiment, digestive fluid is returned from the fermenter 2 to the crushing unit 15, so even if clean water is supplied, However, a small amount of tap water is sufficient.

Further, if there is human waste in the human waste storage tank 11, the human waste is also supplied to the crushing process section 10.
That is, in the present embodiment, the human waste storage tank 11 is connected to the crushing process section 10 via a human waste supply passage 68 that includes a human waste introduction passage 62 and a reflux conveyance passage 60 .
When supplying human waste to the crushing process section 10, the on-off valve 66 of the human waste introduction path 62 is opened, and a series of human waste supply and transport paths 68 from the human waste introduction path 62 to the reflux transport path 60 is opened. Then, the human waste pump 63 is driven.
As a result, the human waste in the human waste storage tank 11 is supplied to the crushing process section 10 together with the digestive fluid supplied from the fermenter 2, as shown by the bold line in FIG.
Since human waste also contains a large amount of water, the chamber of the wet crushing device 31 is filled with liquid, and the garbage is crushed into small pieces in the liquid.
In addition, the solid content in human waste can be crushed and made into a slurry.
The food waste mixed with the digestive fluid and human waste that is finely crushed in the crushing section 15 and returned from the fermenter 2 is sent to the first pressure pump 37 by the discharge conveyor 36 as shown by the arrow in FIG. It is pressurized by the first pressure pump 37 and charged into the fermentation tank 2 through the first feeding conveyance path 50. Digestive fluid is also mixed into the first pressure pump 37 if necessary.

In this embodiment, while the crushing work is being performed in the crushing process section 10, the water level sensor 33 attached to the crushing section 15 monitors the water level within the crushing section 15.
If the water level in the crushing section 15 falls below the position of the water level sensor 33, the flow path adjustment valve 67 provided in the reflux conveyance path 60 is opened to supply more digestive fluid to the crushing section 15.
Conversely, when the water level in the crushing section 15 exceeds the position of the water level sensor 33, the opening degree of the flow path regulating valve 67 provided in the reflux conveyance path 60 is reduced, and the amount of digestive fluid supplied to the crushing section 15 is reduced. decrease.
As a result, the wet type crushing device 31 (wet type side breaking section 28) is filled with liquid, but the dry type crushing device 30 (rough crushing device side breaking section 27) is not filled with liquid, so food waste floating on the water does not float in the dry crushing device 30, and the garbage can be crushed by the dry crushing device 30 to form a slurry.

The above is the flow of fermentation materials in a normal case, but the amount of garbage collected varies.
For example, during the day, workers who collect food waste are working, and the amount of food waste that can be collected is large.
On the other hand, at night, there are fewer workers working and less garbage is collected.
Further, the amount of food waste and human waste to be input into the fermenter 2 also varies.
That is, both the demand for food waste, etc. required for the fermenter 2 and the supply, which is the amount of food waste, etc. to be collected, vary.

In this embodiment, as a measure to equalize the relationship between demand and supply, the entire amount of the fermentation raw material crushed in the crushing process section 10 is carried into the fermenter 2, and the entire amount of the fermentation raw material crushed in the crushing process section 10 is introduced. A part of the raw material for fermentation is transported into the fermenter 2 and the rest is transported into the storage tank 12, and the entire amount of the raw material for fermentation crushed in the crushing process section 10 and the raw material for fermentation in the storage tank 12 are simultaneously charged. Additional input to be carried into the fermenter 2 can be switched.
Further, the entire amount of fermentation raw materials crushed in the crushing process section 10 can be carried into the storage tank 12 to store the entire amount.

As a preferable method of use, the amount of fermentation raw materials crushed in the crushing process section 10 per a certain period of time is larger than the scheduled amount of fermentation raw materials input into the fermenter 2 per certain period of time. Decide where to go.
For example, 3 hours or half a day is set as a fixed time, and the amount of crushed fermentation raw materials crushed in the crushing process section 10 and the amount of fermented raw materials to be input into the fermenter 2 are compared during this period.
When the amount of crushed fermentation raw materials crushed in the crushing process section 10 per given time is larger than the scheduled amount of fermented raw materials input per given time into the fermenter 2, a part of the crushed fermentation raw materials are fermented. A partial charge is carried out in which the liquid is carried into tank 2 and the remaining part is carried into storage tank 12.
When the amount of fermentation raw materials crushed in the crushing process section 10 per certain period of time is less than the scheduled input amount of fermentation raw materials, the fermentation raw materials in the storage tank 12 are added to the total amount of crushed fermentation raw materials. At the same time, additional input is carried out into the fermenter 2.
The destination of the fermented raw material may be changed automatically or manually.

For example, if the amount of collected food waste is larger than the amount of food waste to be supplied to the fermenter 2, a portion of the food waste crushed in the crushing process section 10 will be is sent to the storage tank 12 via the stockpiling conveyance path 78 (partially charged).
That is, the on-off valve 53 provided in the branch pipe 75 is opened to open a series of stockpiling conveyance paths 78 that flow from the first pressure pump 37 of the crushing process section 10 to the branch pipe 75.
As a result, a portion of the garbage passing through the first feeding conveyance path 50 enters the branch pipe 75 and is introduced into the storage tank 12, as indicated by the arrow in FIG.

When the fermenter 2 is full (when there is a large amount of undigested material) and there is no need to newly supply food waste, etc., the on-off valve 51 of the first feeding conveyance path 50 is closed and the thick line in FIG. As shown in the figure, the entire amount of raw garbage crushed in the crushing process section 10 is introduced into the storage tank 12 via the stockpiling conveyance path 78 (total amount storage).

If the amount of garbage collected is even larger, truck B is parked on the storage tank 12 side and put into the storage tank 12.
The food waste discharged from the truck B is finely crushed by the food waste crushing device 47. At this time, clean water is supplied from the clean water circuit 85 to the garbage crushing device 47, and the garbage is mixed with the clean water to form a slurry. The slurry-like garbage is then introduced into the introduction tank 40 of the storage tank 12 by the introduction conveyor 46.
Then, the slurry-like garbage in the introduction tank 40 is conveyed to a screen 43 by a pull-up conveyor 42, large and coarse garbage is removed by the screen 43, and only the finely crushed garbage is transferred to the storage tank 12. stored.

On the other hand, when the stock of food waste decreases, the crushed food waste and human waste stored in the storage tank 12 are supplied to the fermentation tank 2, as shown by the thick line in FIG.
That is, as shown by the thick line in FIG. 8, the entire amount of food waste crushed in the crushing process section 10 is supplied to the fermentation tank 2, and in addition, the food waste in the storage tank 12 is also supplied to the fermentation tank 2. (additional input).
Note that if the stock of food waste is completely exhausted, only the crushed food waste and human waste stored in the storage tank 12 are supplied to the fermentation tank 2.

The temperature of the fermentation raw material in the fermentation tank 2 is controlled by the temperature-controlled circulation conveyance path 20 to carry out methane fermentation (fermentation process). That is, as shown by the thick line in FIG. 9, the fermentation raw material in the fermenter 2 is always taken out to the outside via the temperature-controlled circulation conveyance path 20, and its temperature is controlled by the heat exchanger 26.
The temperature of the hot water on the temporary side of the heat exchanger 26 and the opening degree of the flow path regulating valve 23 are determined by feeding back the temperature detected by the temperature sensor attached to the fermenter 2, and the temperature inside the fermenter 2 is controlled to be constant. Ru.

The fermentation apparatus 1 of the embodiment described above temporarily stores crushed fermentation raw materials in view of the variation in the demand for food waste, etc. required for the fermenter 2, and the supply, which is the amount of food waste, etc. to be collected. A storage tank was installed. This technology can also be applied to fermentation apparatuses with other configurations.
That is, the fermentation apparatus 1 of this embodiment includes a crushing process section 10 for crushing fermentation raw materials and a fermentation tank 2, and introduces the fermentation raw materials crushed in the crushing process section 10 into the fermentation tank 2, and A fermentation device 1 that ferments fermentation raw materials in a fermentation tank 2 includes a storage tank 12 for temporarily storing fermentation raw materials, and a first input conveyance path 50 that connects the crushing process section 10 and the fermentation tank 2; This fermentation apparatus is characterized by having a stockpiling conveyance path 78 that connects the crushing process section 10 and the storage tank 12, and a second input conveyance path 55 that connects the storage tank 12 and the fermentation tank 2.

A preferred method of using this embodiment is as follows.
That is, when a large amount of garbage or human waste is received, such as during the day, a portion of the crushed fermentation raw material is stored in the storage tank 12.
At night, when the amount of garbage etc. received decreases, the fermentation raw material stored in the storage tank 12 is taken out and put into the fermentation tank 2.
If a configuration is adopted in which all the received fermentation raw materials are stored in the storage tank 12 and then put into the fermentation tank 2, it will be necessary to receive extra food waste even if the necessary amount is secured at night. Therefore, the storage tank 12 needs to be quite large.
On the other hand, according to the strategy of the present embodiment, when the fermentation raw material is put into the fermentation tank 2 during the daytime, if the required amount is exceeded, the fermentation raw material is sent to the storage tank 12 side.
According to the configuration of this embodiment, there is no need to increase the volume of the storage tank 12 excessively.

1 Fermentation device 2 Fermentation tank 10 Crushing process section 11 Human waste storage tank 12 Storage tank 15 Crushing section 20 Temperature-controlled circulation conveyance path 25 Circulation pump 26 Heat exchanger 30 Dry crushing device (rough crushing device)
31 Wet crushing device 33 Water level sensor 50 First input conveyance path 55 Second input conveyance path 57 Conveyance path switching means 60 Reflux conveyance path 68 Human waste supply conveyance path 78 Stockpiling conveyance path

Claims (6)

It has a crushing process section for crushing fermentation raw materials, a fermentation tank , and a storage tank for temporarily storing the fermentation raw materials, and the fermentation raw materials crushed in the crushing process section are introduced into the fermentation tank, and the fermentation tank In a fermentation device that ferments fermentation raw materials in
It has a reflux conveyance path for returning moisture in the fermenter to the crushing process section, and
It has a storage tank to temporarily store fermentation raw materials,
a first input conveyance path connecting the crushing process section and the fermenter;
a stockpiling conveyance path connecting the crushing process section and the storage tank;
a second input conveyance path connecting the storage tank and the fermentation tank;
has, and furthermore,
It has a conveyance path switching means,
Injecting the entire amount of the fermentation raw material crushed in the crushing process section into the fermenter;
Partial input of a part of the fermentation raw material crushed in the crushing process section into the fermentation tank and the remaining part into the storage tank;
In addition to the entire amount of fermentation raw materials crushed in the crushing process section, additionally introducing the fermentation raw materials in the storage tank into the fermentation tank at the same time;
A fermentation apparatus characterized by being capable of carrying out . It has a temperature-controlled circulation conveyance path, and the temperature-controlled circulation conveyance path has a heat exchange section in the middle, and the temperature-controlled circulation conveyance path takes out moisture in the fermenter and guides it to the heat exchange section to adjust the temperature. and return it to the fermenter.
It has a pump, the suction side of the pump is connected to the fermenter, the discharge side of the pump is branched, one of the branches is connected to the heat exchange part, and the temperature-controlled circulation conveyance path is configured. The fermentation apparatus according to claim 1, wherein the reflux conveyance path is constituted by another one of the branches. Fermentation according to claim 1 or 2, characterized in that it has a human waste storage tank for storing animal excrement and urine, and a human waste supply conveyance path that sends the human waste stored in the human waste storage tank to the crushing process section. Device. The crushing process section has a rough crushing device and a wet crushing device, and the wet crushing device is disposed downstream of the rough crushing device, and the fermentation raw material crushed by the rough crushing device is further 4. The fermentation device according to claim 1, wherein the fermentation device is crushed using a wet crushing device. In the crushing process section, the rough crushing device and the wet crushing device are arranged above and below each other, and the two are connected directly or through a pipe,
A water level sensor is provided between a breaking section on the coarse crushing device side where the fermentation raw material is broken in the rough crushing device and a breaking section on the wet side where the fermentation raw material is broken in the wet crushing device. The fermentation apparatus according to claim 4. When the amount of fermentation raw materials crushed in the crushing process section per certain period of time is larger than the scheduled amount of fermentation raw materials to be input into the fermenter per constant time, the fermentation raw materials crushed in the crushing process section. Partial input is carried out in which a part of the fermentation tank is carried into the fermentation tank and the remainder is carried into the storage tank,
When the amount of fermentation raw materials crushed in the crushing process section per certain period of time is smaller than the scheduled amount of fermentation raw materials to be input into the fermenter per certain time, the fermentation raw materials crushed in the crushing process section. 2. The method of using a fermentation apparatus according to claim 1, further comprising the step of simultaneously carrying the fermentation raw material in the storage tank into the fermentation tank in addition to the total amount of the fermentation tank.

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