JP2002018398A - Device and method for reducing volume of garbage by using fermenter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently subject garbage to anaerobic treatment by finely crushing the garbage and fermenting the same and by efficiently diffusing the occurred sludge and scum within a fermenter to reduce the volume thereof to stable dischargable matter consisting of gaseous methane, etc., and water. SOLUTION: This device has a tank for feeding organic wastes, the fermenter, a draft tube containing a screw type agitating machine of a vertical type at its center, a feeding pipe connected to the side part of the draft tube through the side wall of the fermenter and a force feed pump. As a more adequate embodiment, a bypass circuit from the side wall of the fermenter to the bottom of the fermenter is annexed to the ferementer and the portions of the contents are blown off into the fermenter from its bottom, by which the sludge accumulated on the bottom of the feremen is agitated by blowing the sludge. The top end of the fermenter is provided with an overflow mechanism for preventing the formation of the scum.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for performing anaerobic treatment by finely crushing and fermenting garbage, decomposing it into methane gas and other water, and reducing the volume, and reducing the volume using the apparatus. About how to convert.

[0002]

2. Description of the Related Art Generally, organic wastes such as garbage are incinerated and landfilled together with other general wastes. However, shortage of landfills requires reduction of the volume of garbage. It has become. A system for fermenting organic matter by anaerobic bacteria and converting it to methane has been used and put into practical use for a long time. In particular, it is still used for the treatment of human waste and for the treatment of excess sludge generated from activated sludge in terminal sewage treatment plants, and methane is used as a heat source and the volume is reduced.

Japanese Patent Application Laid-Open Nos. 60-78698 and 78699 disclose "2" for fermenting biomass such as sewage sludge.
Phase two-tank methane fermentation apparatus ". Japanese Patent Application Laid-Open No. 11-77005, "Methane fermentation method of organic waste", discloses a method of anaerobic treatment of organic waste using an acid fermentation tank and a methane fermentation tank to remove and separate impurities. ing. However, in these prior arts, as shown in FIG. 10 of the accompanying drawings, organic waste and sludge having a large specific gravity settle at the bottom of the fermenter 1, and the chance of contact between the acid fermentation bacteria and the organic waste decreases. There are drawbacks such as a decrease in the rate of solubilization of organic waste and a decrease in the rate of gasification of the organic acid due to a reduced chance of contact between the methane fermentation bacterium and the organic acid. Further, as shown in FIG. 11, sludge floats together with gas and scum is generated at the upper part of the fermenter 1, so that the rate of solubilization of organic waste decreases, the rate of gasification of organic acid decreases, and However, there is a drawback that the scum prevents the liquid from flowing out of the liquid into the air, and the rotary scum scraping mechanism 90 and the like are provided.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to carry out anaerobic treatment by finely crushing and fermenting garbage, and to effectively diffuse sediment sludge and scum in a fermentation tank to produce methane gas and the like. And to reduce the volume to a stable discharge consisting of water and water.

[0005]

An apparatus according to the present invention is an apparatus for reducing the volume of organic waste after removing contaminants from garbage and crushing the same by using a fermenter. Is realized by: In a first aspect, the device comprises:
A tank for charging organic waste, a fermenter, a draft tube extending vertically in the fermenter and incorporating a vertical screw-type agitator in the center, and penetrating the side wall of the fermenter. An input pipe connected to the side of the draft tube is provided, and a pump for pumping organic waste from the tank to the input pipe is provided.

[0006] In a second aspect, the apparatus comprises a fermenter, a draft tube extending vertically in the fermenter and having a vertical screw-type agitator built in the center, and a side wall of the fermenter. A bypass outlet, an outlet provided at the bottom of the fermenter, a connection circuit from the bypass outlet to the outlet, and a pump provided in the connection circuit. The method is characterized in that a part of the material flows out and is blown out from the outlet into the tank to blow off and mix the sludge accumulated at the bottom of the fermenter.

In a third embodiment, the apparatus comprises a fermenter, a draft tube extending vertically in the fermenter and having a vertical screw-type stirrer built in the center, and a draft tube formed at the upper end of the fermenter. And a scum generation preventing overflow mechanism installed so as to cover the constricted portion. The scum generation preventing overflow mechanism prevents scum generation by overflowing contents from the upper end of the fermenter. It is characterized by:

[0008] In a fourth aspect, the apparatus comprises a tank for charging organic waste, a fermenter, a charging pipe connected to a side wall of the fermenter, and the organic waste from the tank. A pump for pumping to a pipe, and an activated carbon charging circuit for charging powdered activated carbon into the tank or the fermenter or a system thereof are provided, and the aggregation of sludge is promoted by charging the powdered activated carbon. .

[0009]

The operation according to the first aspect of the present invention is as follows. In the conventional fermenter, organic waste was injected from an input port provided on a side wall of the fermenter, so that the waste immediately after the input was difficult to diffuse. In the present invention, since the organic waste is pressure-fed from the input pipe connected to the side of the draft tube incorporating the screw agitator, it is immediately transferred upward (or downward) by the screw, The stirring speed is improved and the processing efficiency is increased.

The operation according to the second aspect of the present invention is as follows. As described above, in the conventional fermentation tank, organic waste and sludge having a large specific gravity are precipitated at the bottom, and the chance of contact between the acid fermentation bacteria and the organic waste is reduced, and the solubilization rate of the waste is reduced, There are drawbacks such as a reduced chance of contact between the methane fermentation bacterium and the organic acid and a reduction in the gasification rate of the organic acid. According to the present invention, a part of the contents of the fermenter is flowed out from the bypass outlet and blown out from the blowout port into the tank, and the sludge accumulated at the bottom of the fermenter is blown off and stirred. The sludge is prevented from settling, and various defects associated with the settling can be removed.

The operation according to the third aspect of the present invention is as follows. As mentioned above, in conventional fermenters, sludge floats together with gas and forms scum (floating bubbles) at the upper part of the fermenter, so the rate of solubilization of organic waste decreases and gasification of organic acids occurs. There are drawbacks such as a decrease in the speed and the scum preventing the gas from flowing out of the liquid into the air. According to the present invention, the scum generation prevention overflow mechanism is provided at the upper part of the fermenter, and the content flows out so as to overflow from the upper part. Therefore, the generation of scum itself is prevented, and the scum is removed. There is no need to provide a scraping mechanism or the like.

The operation according to the fourth aspect of the present invention is as follows. According to the present invention, an activated carbon charging circuit for charging powdered activated carbon into a tank, a fermenter, or a system thereof is provided, so that powdered activated carbon serves as a nucleus to promote the aggregation of sludge.

According to a fifth aspect of the present invention, an organic waste after removing contaminants from garbage and crushing is converted into an organic acid using an acid fermentation tank and is anaerobic using a methane fermentation tank. A method of treating and reducing the volume, in which organic waste is pumped into an acid fermentation tank by a pump, and the organic waste in the tank is bottomed by a screw type agitator having a vertical axis provided inside the acid fermentation tank. From the top to the top, overflow the organic waste from the scum formation prevention overflow mechanism provided at the top of the acid fermentation tank, and transfer a portion of the overflowed organic waste to the methane fermentation tank, The remaining part is blown into the tank from the outlet provided at the bottom of the acid fermentation tank, and the sludge accumulated at the bottom of the acid fermentation tank is blown off and stirred, and the acid fermentation tank is turned into the tank of the methane fermentation tank. Pumping the organic waste sent,
The organic waste in the tank is transported upward from the bottom to the top by a screw stirrer with a vertical axis installed inside the methane fermentation tank, and the organic waste is discharged from the scum formation prevention overflow mechanism installed at the top of the methane fermentation tank. The spilled material and a part of the overflowed organic waste were transferred to the outside of the system, and the remaining part was blown out of the methane fermentation tank through an outlet provided at the bottom of the methane fermentation tank to form a bottom of the methane fermentation tank. A method for reducing the volume of garbage, characterized by blowing and stirring the sludge accumulated in the garbage.

The method according to the present invention comprises an acid fermenter for solubilizing garbage and converting it to an organic acid in the process of anaerobically decomposing garbage and treating it with methane gas and water to reduce its volume. This is a two-tank system having a methane fermentation tank that converts an acid into methane gas or the like, and has the following features.

[0015] The high-molecular organic matter in the garbage is directly introduced into a draft tube installed in the acid fermentation tank for the purpose of improving the stirring efficiency, and the sludge containing microorganisms is removed by a screw-type stirrer. Stir well. Some sludge containing organic substances and microorganisms in the fermenter settles at the bottom of the tank. In order to prevent this, a sludge blowing mechanism is provided in the tank. By this mechanism, the settled sludge is diffused and homogenized by a screw type stirrer.

The sludge that has floated together with the gas in the fermenter to form scum is unevenly distributed in the upper part of the fermenter. For the purpose of removing this, a scum generation prevention overflow mechanism is provided in the tank, the scum is discharged from the tank, heated in the heating tank, and then blown out from the bottom of the tank by the pump. It is homogenized and returned to the tank. Thereby, scum uneven distribution is prevented in the tank.

In order to activate the microorganisms in the acid fermentation tank, it is necessary to promptly discharge the generated organic acid, which is a metabolite, from the acid fermentation tank. Therefore, for the purpose of pushing out the organic acid from the acid fermentation tank, a mechanism is provided for feeding the desorbed liquid taken out from the methane fermentation tank using a solid-liquid separator or the like to the acid fermentation tank. The desorbed liquid is sent at a flow rate such that the organic acid concentration is within a certain range, and is directly charged into a draft tube installed in the acid fermentation tank. And is efficiently stirred. This makes it possible to discharge the organic acid from the acid fermenter.

In the present invention, various specific techniques can be added to obtain more preferable results. For example, the desorbed liquid flowing out of the methane fermentation tank may be sent to a draft tube of the acid fermentation tank to push out the organic acid from the acid fermentation tank. In addition, powdered activated carbon can be charged into an acid fermentation tank and / or a methane fermentation tank or a system to serve as a nucleus of microorganisms and promote flocculation of sludge.

Using the method having the characteristics described above, the method for reducing the volume of garbage according to the present invention performs the following processing. First, garbage from which contaminants have been removed in advance is mechanically pulverized finely and subjected to anaerobic treatment with a digested sludge that has been acclimated in an acid fermentation tank and a methane fermentation tank in a two-tank digestion method. Is adjusted to 5.0 to 7.0, and the pH is adjusted to 7.0 to 8.0 in the methane fermentation tank. The temperature in both tanks is, for example, 30 to 35 ° C or 50 to 55 ° C.
The pH of the acid fermentation tank is adjusted by adding an alkali agent and returning the liquid desorbed from the methane fermentation tank containing an alkali component. The organic acid that causes the pH in the acid fermentation tank to decrease is rapidly discharged. In the methane fermentation tank, the organic acid from the acid fermentation tank is a substance that lowers the pH in the tank, but is rapidly removed as a gas outside the system because it is decomposed by methane bacteria. Thus, in the system of the present invention, the volume of garbage can be easily reduced by easy pH control.

[0020]

FIG. 1 corresponds to a first embodiment of the present invention. This apparatus uses a fermenter to reduce organic waste after removing contaminants from garbage and crushing the same. A tank 5 for charging organic waste, a fermenter 1, and a draft tube 2 extending vertically in the fermenter 1 and incorporating a vertical screw-type agitator 3 in the center.
A feed pipe 8 penetrating the side wall of the fermenter 1 and connected to the side of the draft tube 2; and a pump 7 for pumping organic waste from the tank 5 to the feed pipe 8.

Air is pressure-fed from a stirring blower 6 to the tank 5, and a predetermined stirring operation is performed in the tank. The screw type agitator 3 is driven by a motor 4. A well-known temperature sensor T is installed in the fermentation tank, and the inside of the tank is maintained at a predetermined temperature. Scum S is generated on the liquid surface in the tank. The processed contents are sent to the outside through the outlet 9. Thus, the organic waste is pumped from the input pipe 8 connected to the side of the draft tube 2 containing the screw type agitator 3, so that the waste immediately after the input is sucked by the negative pressure and immediately upward by the screw. And the stirring speed is improved, thereby improving the processing efficiency.

FIG. 2 corresponds to a second embodiment of the present invention. This apparatus incorporates a fermenter 1 and a vertical screw-type agitator 3 which extends vertically in the fermenter 1 and is centrally provided. Draft tube 2, bypass outlet 10 provided on the side wall of fermenter 1, outlet 14 provided on the bottom of fermenter, connection circuit (bypass circuit) 11 from bypass outlet 10 to outlet 14, connection circuit And a pump 13 provided therein. In the illustrated example, the heating tank 12 is provided in the connection circuit.
Are arranged, but may be omitted.

FIG. 3 shows that a liquid containing sludge is blown out from an outlet 14 provided at the bottom of the fermenter 1 to stir the inside of the tank, so that sludge and scum settle or remain in the tank. This indicates a state in which is prevented. This allows
Sludge containing garbage and microorganisms having a large specific gravity can be soared from the bottom of the fermenter. In addition, there are advantages that the opportunity for contact between acid fermentation bacteria and garbage increases, so that the rate of solubilization of garbage increases, and the opportunity for contact between methane bacteria and organic acids increases, and the gasification rate of organic acids increases. can get.

FIG. 4 corresponds to a third embodiment of the present invention. This apparatus comprises a fermentation tank (acid fermentation tank or methane fermentation tank) 15, which extends vertically in the fermentation tank 15 and has a vertical center. Tube 2 containing a screw-type stirrer 3 of the mold type, and a constricted portion 17 formed at the upper end of the fermenter 15.
And a scum generation prevention overflow mechanism 18 installed to cover the constricted portion 17. The scum generation prevention overflow mechanism 18 prevents the generation of scum by overflowing the contents from the upper end of the fermenter 15.

FIG. 5 shows a state in which the sludge and the contents which have been stirred and pushed upward from the scum formation preventing overflow mechanism 18 provided at the upper part of the fermenter 15 are transferred to the downstream side by overflowing. ing. Based on such a configuration, the scum is prevented from being unevenly distributed on the fermenter 15. As a result, the chance of contact between microorganisms and garbage increases, solubilizing rate of organic matter increases, and the chance of contact between microorganisms and organic acid increases, and the gasification rate of organic acid increases. In addition, there is an advantage that the gas can easily escape from the liquid to the air.

FIG. 6 corresponds to a fourth embodiment of the present invention, in which the apparatus comprises a fermenter 1, a conventional input pipe 8 a connected to the side wall of the fermenter 1, and organic waste from the tank 5. The pump 7 is provided with a pump 7 for pressure-feeding the material to the charging pipe 8a, and an activated carbon charging circuit 24 for charging powdered activated carbon into the tank 5 or the fermenter 1 or a system thereof. Thus, there is an effect that the flocculation of the sludge is promoted by the introduction of the powdered activated carbon.

FIG. 7 shows a system for reducing the volume of garbage according to a fifth embodiment of the present invention. This system removes contaminants from garbage and crushes the organic waste to remove acid. It is a device for reducing the volume by anaerobic treatment using the fermenter 16 and the methane fermenter 50, and a draft tube that extends vertically in each fermenter and has a vertical screw-type agitator 3 built in the center. 2 are provided.

In the upper part of each fermenter, scum generation preventing overflow mechanisms 18 and 58 are provided for overflowing the contents from the upper end while preventing scum generation. Solid-liquid separators 34 and 74 are provided downstream of each fermenter, and blowout ports 14 and 60 are provided at the bottom of each fermenter.

Further, a heating tank 12, a heating circulation pump 13 and a coagulation adjusting tank 26 are provided downstream of the acid fermentation tank 16, and a sludge return pump 36 is connected to the bottom of the solid-liquid separation tank 34. Have been. Similarly, on the downstream side of the methane fermentation tank 50, a heating tank 62, a heating circulation pump 64, a coagulation adjusting tank 6
6 is provided, and a sludge return pump 76 is connected to the bottom of the solid-liquid separation tank 74. A part of the liquid withdrawn from the middle of the solid-liquid separation tank 74 is discharged to the outside of the system.
Will be re-introduced. Coagulants are supplied to the coagulation adjusting tanks 26 and 66 from a coagulant dissolving device 37 and a coagulant charging pump 38 (FIGS. 8 and 9).

Thus, in this system, a part of the organic waste overflowing from the scum overflow mechanisms 18 and 58 is transferred to the solid-liquid separators 34 and 74, and the remaining part is disposed at the bottom of each fermenter. The sludge accumulated at the bottom of each fermentation tank is blown out from the provided outlets 14 and 60 to blow off and stir.

[0031]

8 and 9 show a whole volume reduction system according to a further preferred embodiment of the present invention, which is separated into right and left sides in relation to the drawing size. An example of the processing steps in the present invention based on this system is as follows. (1) Remove contaminants such as packs, trays, wraps, and metals from garbage. (2) The garbage is pulverized, charged into the raw material storage tank 5, and supplied to the acid fermentation tank 16 by the raw material charging pump 7.

(3) Carbohydrates, proteins,
High molecular organic matter such as lipids is fed under pressure to a feed pipe 8 provided at the side of the acid fermentation tank, and is directly sent into a draft tube 2 having a screw type agitator 3 having a vertical axis and containing microorganisms. It is efficiently stirred with sludge containing. Thereby, the organic matter in the acid fermenter is rapidly solubilized. (4) The solubilized organic substances are finally decomposed by a microbial reaction into volatile lower fatty acids (mainly acetic acid, butyric acid, propionic acid, etc.), carbon dioxide gas, hydrogen sulfide, and the like. Released outside the system. On the other hand, the settled sludge containing organic matter and microorganisms is stirred by the pump 13 and the blow-out port 14 acting as a sludge blow-off mechanism at the bottom of the tank, and is homogenized by the screw type stirrer 3.

(5) The sludge which tends to float with the gas in the acid fermentation tank and generate scum is overflowed by a scum generation prevention overflow mechanism 18 provided above the acid fermentation tank, and a part of the sludge is methane fermentation tank. After being mostly heated in the heating tank 12, it is returned to the tank by the pump 13 so as to be blown out from the outlet 14 at the bottom of the tank. This makes the sludge uniform. (6) As a result, organic acids are generated and accumulated in the acid fermentation tank, so that the pH is lowered. On the other hand, the optimal microbial environment in the acid fermenter is pH = 5.0-7.0. Therefore, it is necessary to adjust the pH. In the apparatus of the present invention, an alkali as a pH adjuster is fed into the acid fermenter in batches by using the dissolving device 30 and the charging pump 32. The pH adjuster is directly charged into the draft tube 2 provided in the acid fermentation tank, and is efficiently stirred with the sludge containing microorganisms by the upward flow of the screw agitator 3.

(7) On the other hand, in order to activate the microorganisms, it is necessary to promptly discharge the generated organic acid which is a metabolite from the acid fermenter. Therefore, in the apparatus of the present invention, for the purpose of pushing out the organic acid from the acid fermentation tank,
A pump 70 is provided as a device for sending the desorbed liquid taken out of the methane fermentation tank using a solid-liquid separation device or the like to the acid fermentation tank. The desorbed liquid is sent at a flow rate such that the concentration of the organic acid in the acid fermenter is within a certain range. The pH in the acid fermenter is kept at 5.0 to 7.0. The desorbed liquid is directly charged into the draft tube 2 provided in the acid fermenter, and is efficiently stirred with the sludge containing microorganisms by the upward flow of the screw type agitator 3. This makes it possible to quickly discharge organic acids from the acid fermentation tank as a whole system. (8) The sludge, water, and undecomposed organic matter in the acid fermentation tank are injected into the solid-liquid separation tank 34 by a difference in head due to the input organic waste, pH adjuster, and desorbed liquid. A polymer coagulant is added to the sludge and the undecomposed organic matter in the coagulation adjusting tank 26, and the efficiency of solid-liquid separation of the sludge and the undecomposed organic matter is increased. The sludge settled in the solid-liquid separation tank 34 and the undecomposed organic matter are directly fed together with the organic waste into the draft tube 2 in the acid fermentation tank by the sludge return pump 36, and the upward flow of the screw type agitator 3 is performed. Thereby, it is efficiently stirred with the sludge containing microorganisms.

(9) The sludge that has floated together with the gas to form scum is discharged from the upper part of the tank by a rotary or other well-known scum removing mechanism 40 provided in the solid-liquid separation tank 34, and the water and organic matter are removed. The scum is stored in the scum storage tank 42 together with the acid, organic acid salt, undecomposed soluble and insoluble organic matter. Here, after degassing, the scum return pump 44 directly feeds the organic waste into the draft tube 2 in the acid fermentation tank together with the organic waste, and efficiently mixes the sludge containing microorganisms with the upward flow of the screw agitator 3. Is done. On the other hand, the separated water withdrawn from the middle part of the solid-liquid separation tank 34 is
After being temporarily stored in the separated liquid storage tank 43 through 1, it is immediately charged directly into the draft tube 52 provided in the methane fermentation tank by a head difference or a pump,
By the upward flow of the screw type agitator 3, the sludge containing microorganisms is efficiently agitated. (10) On the other hand, in order to improve the solid-liquid separation capacity in the solid-liquid separation tank 74,
The powdered activated carbon can be introduced into the system or the fermenter via 4 to be used as the core of microorganisms. Thereby, the solid-liquid separation efficiency is improved.

(11) The separated water flowing out of the acid fermentation tank 16 and separated by the solid-liquid separation tank 34 is a volatile lower fatty acid (acetic acid, butyric acid, propionic acid, etc.) corresponding to the amount of garbage.
, Organic acid salts, and soluble and insoluble undecomposed organic substances. PH in the methane fermentation tank 50 is set as a microbial environment.
= 7.0 to 8.0, the temperature is, for example, 30 to 35 ° C. or 50 to 55 ° C., ORP = −400 mV (generally) or less, and the pH conditions are different from those of the acid fermentation tank. The organic acid salted by the alkali and the separated water containing the organic acid are directly charged into the draft tube 2 provided in the methane fermentation tank, and the microorganisms are contained by the upward flow of the screw agitator 3. It is efficiently stirred with sludge. As a result, the organic acids and undecomposed organic substances are gasified by a microbial reaction, converted into carbon dioxide gas, hydrogen sulfide, methane gas and the like, and discharged out of the system. (12) Methane gas and the like discharged out of the system
8 removes hydrogen sulfide. After that, the methane gas and the like are stored in the gas holder 79, and are effectively used as a heat source of the boiler. Finally, the methane gas and the like are discharged to the outside by the exhaust blower 77. In this embodiment, an electric heater (EH) is used for heating the fermenter, but the generated methane gas may be used as a heat source for heating.

(13) On the other hand, the settled sludge containing the organic matter and the microorganisms is stirred by the pump 64 and the outlet 60 which function as a sludge blowing mechanism at the bottom of the tank.
It is homogenized by the screw type stirrer 3. (14) Sludge that tends to float with the gas and become scum is removed from the inside of the methane fermentation tank by the scum generation prevention overflow mechanism 58 provided above the methane fermentation tank and heated in the heating tank 62. The water is blown out from the outlet 60 at the bottom of the tank by the pump 64 to make the tank uniform and returned to the inside of the tank.

(15) The sludge, water and undecomposed organic matter in the methane fermentation tank are introduced into the solid-liquid separation tank 74 by a difference in head due to the inputted organic waste, pH adjuster and desorbed liquid.
A polymer flocculant is added in advance to the sludge and the undecomposed organic matter in the coagulation adjusting tank 66 to improve the efficiency of solid-liquid separation of the sludge and the undecomposed organic matter. In the solid-liquid separation tank 74,
The sedimented sludge and the undecomposed organic matter are directly fed into the draft tube 52 in the methane fermentation tank together with the separated water containing the organic acid, the organic acid salt, and the undecomposed organic matter by a sludge return pump 76, and a screw By the stirrer 3, the sludge containing microorganisms is efficiently stirred. (16) Further, the sludge that floats with the gas to form scum is discharged from the upper part of the tank by a scum removal mechanism 80 such as a rotary type provided in the solid-liquid separation tank 74, and the water, organic acid, and organic acid salt are removed. Is stored in the scum storage tank 82 together with undecomposed soluble and insoluble organic matter. After being degassed here, the scum return pump 84 is directly charged into the draft tube 52 in the methane fermentation tank, and is efficiently stirred with the sludge containing microorganisms by the upward flow of the screw type agitator 3.

(17) On the other hand, the separated water withdrawn from the intermediate portion of the solid-liquid separation tank 74 is temporarily stored in the separated liquid storage tank 83 via the water level adjustment tank 81, and then a part of the separated water is removed. It is returned to the acid fermentation tank 10 by the system return pump 70, and is effectively used for pushing out the organic acid in the acid fermentation tank and adjusting the pH. A part of the separated water is treated by a post-treatment facility 86 to a water quality satisfying a discharge standard, and then discharged by a sewer.

[0040]

As described above in detail, according to the apparatus and method for reducing the volume of garbage according to the present invention, when performing anaerobic treatment by finely crushing and fermenting garbage, the garbage remains in the fermentation tank. The generated sludge and scum can be effectively treated and reduced in volume to a uniform effluent composed of methane gas or the like and water. The technical effects are extremely remarkable.

[Brief description of the drawings]

FIG. 1 is a schematic view of a garbage volume reducing apparatus according to a first embodiment of the present invention.

FIG. 2 is a schematic diagram of a garbage volume reducing device according to a second embodiment of the present invention.

FIG. 3 is a plan view and a sectional view showing a sludge outlet.

FIG. 4 is a schematic view of a garbage volume reducing device according to a third embodiment of the present invention.

5A and 5B are a plan view and a cross-sectional view illustrating a scum generation prevention overflow mechanism.

FIG. 6 is a schematic diagram of a garbage volume reducing device according to a fourth embodiment of the present invention.

FIG. 7 is a schematic diagram of a garbage volume reducing system according to a fifth aspect of the present invention.

FIG. 8 is a circuit diagram illustrating a left half of a garbage reduction system according to an embodiment of the present invention.

FIG. 9 is a circuit diagram illustrating a right half of a garbage reduction system according to an embodiment of the present invention.

FIG. 10 is a plan view and a sectional view showing a sludge sedimentation state of a conventional fermenter.

FIG. 11 is a side sectional view showing a scum accumulation state of a conventional fermenter.

[Explanation of symbols]

 1,15 Fermentation tank 2 Draft tube 3 Stirrer 5 Raw material storage tank 7 Raw material input pump 8,52 Input pipe 10 Bypass outlet 11 Bypass circuit 13,64 Pump 14,60 Outlet 16 Acid fermentation tank 18,58 Scum generation prevention overflow mechanism 22 Activated carbon input section 24 Activated carbon input circuit 50 Methane fermentation tank 70 Desorbed liquid return pump

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[Procedure amendment]

[Submission date] August 8, 2000 (200.8.8)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0021

[Correction method] Change

[Correction contents]

Air is pressure-fed from a stirring blower 6 to the tank 5, and a predetermined stirring operation is performed in the tank. The screw type agitator 3 is driven by a motor 4. A well-known temperature sensor T is installed in the fermentation tank, and the inside of the tank is maintained at a predetermined temperature. Scum S is generated on the liquid surface in the tank. The processed contents are sent to the outside through the outlet 9. Thus, the organic waste is pressure-fed from the input pipe 8 connected to the side of the draft tube 2 containing the screw-type agitator 3, so that the organic waste is immediately transferred upward by the screw, and the stirring speed is improved. As a result, the processing efficiency is improved.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Shoji Koyama 2-4 Yotsuya Shinjuku-ku, Tokyo Shinryo Corporation Industrial Co., Ltd. (72) Inventor Masaro Tsukamoto 2-4 Yotsuya Shinjuku-ku Tokyo 4D004 AA03 BA03 CA04 CA12 CA18 CA35 CA48 CB27 CB32 CB44 CB45 CC11 DA02 DA06 4D059 AA07 BA12 BA14 BA15 BA17 BA51 BA56 BF02 BF13 BJ02 BK01 CA16 CC03 EA05 EA06 EB05 EB06

Claims (7)

[Claims] An apparatus for reducing the volume of organic waste after removing impurities from garbage and crushing the same by using a fermenter, comprising: a tank for charging the organic waste; a fermenter; A draft tube that extends vertically in the fermenter and has a built-in vertical screw stirrer in the center, and a feed tube that penetrates the side wall of the fermenter and is connected to the side of the draft tube. And a pump for pumping organic waste from the tank to the charging pipe. 2. An apparatus for reducing the volume of organic waste after removing contaminants from garbage and crushing using a fermenter, comprising: a fermenter; and extending vertically in the fermenter. And a draft tube incorporating a vertical screw stirrer in the center, a bypass outlet provided on the side wall of the fermenter, an outlet provided at the bottom of the fermenter, and a outlet from the bypass outlet to the outlet. A connection circuit, and a pump provided in the connection circuit, wherein a part of the contents of the fermentation tank flows out from the bypass outlet and is blown out into the tank from the blowout port to accumulate sludge at the bottom of the fermentation tank. A garbage reduction device characterized by blowing and stirring. 3. An apparatus for reducing the volume of organic waste after removing impurities and crushing from garbage using a fermenter, comprising: a fermenter; and a vertically extending fermenter. And a draft tube having a vertical screw-type stirrer built-in at the center, a constricted portion formed at the upper end of the fermenter, and a scum generation preventing overflow mechanism installed to cover the constricted portion. A garbage reduction device characterized in that the prevention overflow mechanism prevents the generation of scum by overflowing the contents from the upper end of the fermenter. 4. An apparatus for reducing the volume of organic waste after removing contaminants from garbage and crushing the same by using a fermenter, comprising: a tank into which the organic waste is charged; An input pipe connected to a side wall of the fermenter, a pump for pumping organic waste from the tank to the input pipe, and inputting powdered activated carbon into the tank or the fermenter or a system thereof. A garbage reduction device, comprising: an activated carbon charging circuit, wherein powder activated carbon is charged to promote sludge aggregation. 5. A method in which organic waste after removing contaminants from garbage and crushing is converted into an organic acid using an acid fermentation tank, and is subjected to anaerobic treatment using a methane fermentation tank to reduce the volume. The organic waste is pumped into the acid fermentation tank by a pump, and the organic waste in the tank is transferred upward from the bottom to the top by a screw agitator having a vertical axis provided in the acid fermentation tank. The organic waste is spilled out of the scum formation prevention overflow mechanism provided at the top of the acid fermentation tank, a part of the overflowed organic waste is transferred to the methane fermentation tank, and the remaining part is transferred to the acid fermentation tank. The organic waste sent from the acid fermentation tank into the methane fermentation tank by blowing and stirring the sludge accumulated at the bottom of the acid fermentation tank through the outlet provided at the bottom of the tank With a vertical axis set inside the methane fermentation tank. The organic waste in the tank is transferred upward from the bottom to the top by a clew-type stirrer, and the organic waste is overflowed from the scum formation prevention overflow mechanism provided at the top of the methane fermentation tank, and the organic waste that has overflowed Part of the methane fermentation tank is blown out of the system, and the remaining part is blown out of the methane fermentation tank through an outlet provided at the bottom of the methane fermentation tank to blow off and mix the sludge accumulated at the bottom of the methane fermentation tank. A method for reducing the volume of garbage. 6. The method according to claim 5, wherein the effluent discharged from the methane fermentation tank is fed into the acid fermentation tank to push out organic acids from the acid fermentation tank. 7. The method according to claim 5, wherein powdered activated carbon is charged into an acid fermentation tank and / or a methane fermentation tank or into a system to make the core of microorganisms.