JPH07241542A - Method and apparatus for fermentation of organic material - Google Patents

Abstract

PURPOSE:To uniformly and efficiently subject to an org. material to fermentation treatment. CONSTITUTION:An org. material is frequently stirred while the water content thereof is kept under air supply environment regulated in temp. to be subjected to aerobic fermentation. A fermentation treatment apparatus is constituted of a hermetically closed fermentation tank 1, the stirring device 20 installed in the fermentation tank 1, an air supply device 9b capable of regulating temp. and air quantity, a deodorizing and exhaust device 10a for the gas from the interior of the fermentation tank and a water sprinkler 12 capable of regulating temp. and a flow rate. Therefore, the org. material can be held under environment suitable for fermentation and can be subjected to uniform fermentation treatment at high speed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to municipal waste, livestock manure,
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fermentation treatment method and treatment device for high-speed fermentation treatment of organic materials such as wastes from agriculture, forestry and fisheries and food processing industries and sludge.

[0002]

2. Description of the Related Art Conventionally, organic wastes such as municipal solid wastes, agricultural, forestry, water and livestock and food processing industry wastes are mainly incinerated, used for landfill, or disposed at a final disposal site. In addition, it has been put into practical use that animal manure and some municipal solid waste are aerobically fermented to be composted and directly used for agricultural products. By the way, in the above-mentioned incineration of organic waste, a large amount of carbon dioxide, nitrogen oxides (NOx),
Sulfur oxides (SOx) are released into the atmosphere, causing global warming, acid rain, air pollution, etc. These are beginning to adversely affect the food chain and even the biological ecosystem. . For this reason, it is considered that the organic waste is also subjected to fermentation treatment to reduce its volume as in the case of the above-mentioned composting, and this method can be said to be an environmentally friendly treatment method compared to landfill or incineration. In any case, fermenting organic waste, which is an organic material, for composting or volume reduction is an effective method for reducing the amount of waste.

Various types of composting devices have been proposed in the past, and one of them has been proposed, for example, in Japanese Examined Patent Publication No. 64-1.
There is a scoop type composting device as shown in Japanese Patent No. 435. The scoop-type composting device transfers the processing material to be put into the fermentation tank while stirring it with a stirring transfer device (scoop type), and at the same time, it lowers the air below the tank consisting of a punching plate against the accumulated processing material. By constantly ventilating the room, aerobically fermenting it to compost. In addition to the scoop type composting device, there are Dano type and paddle type composting devices. In both methods, air is supplied from the lower side of the processing material, and at the same time, the processing material is supplied by each agitator. Stir it.

[0004]

However, in the conventional composting apparatus as described above, as the composting apparatus is operated for a long period of time, one of the treated materials and the wood chips on the bottom surface of the fermenter is The parts stick to each other, and these are piled up to be compressed and hardened into a plate shape. This phenomenon is particularly remarkable in the part where the excess water on the raw material feeding part side is not yet sufficiently discharged, and the plate-shaped hardening part is formed over the half of the length of the fermentation tank from the processing material feeding part side. However, it has the disadvantage that it becomes difficult for water and air to pass through, hinders air diffusion from the bottom of the tank, and significantly impairs the uniformity of ventilation. For this reason, dehydration of the input processing material and blowing of air into the processing material become insufficient, causing an anaerobic fermentation state and causing a bad odor, or delaying composting and increasing the capacity of the composting device. It was the cause of the decrease.

On the other hand, there is also a method in which the ventilation air is forcibly sent from the entire bottom surface of the tank. However, in this method, the air easily flows along the wall of the tank where the resistance is low, the air flows more toward the processing material near the wall, and only a small amount flows into the processing material in the middle part apart from the tank wall. The phenomenon occurs.
Therefore, since the air required for the activity of aerobic microorganisms in the treated material cannot be uniformly supplied to the entire deposited treated material in the same tank, there is a disadvantage that good aerobic fermentation is not performed in some parts. In particular, since the treatment material is usually deposited and allowed to stand for at least a certain period of time, it is considered that the oxygen concentration in the aerated air greatly differs depending on the position inside the treatment material due to the above phenomenon, and the reaction rate is considerably different. To be For this reason, a stirring operation called "cut back" is regularly performed, but it is difficult to ensure the uniformity of the air concentration by normal stirring, and it can be said that the reaction state inside the fermenter is extremely uneven. . A method of increasing the number of times of stirring or aeration with a large amount to promote the reaction can be considered, but there is a problem that the temperature of the treatment material is lowered and the reaction is rather hindered. It is an object of the present invention to improve such conventional non-uniform aeration and make it uniform as much as possible to perform good aerobic fermentation of the entire treated material in the fermenter.

[0006]

[Means for Solving the Problems] A composting device is a device for putting a treatment material in a fermenter and fermenting the processed material to form a compost. The composting reaction is a kind of fermentation reaction involving microorganisms and is an oxidation reaction. Oxygen supplied to the processing material is consumed and microorganisms grow, and in parallel with this, decomposition of the processing material proceeds. Microorganisms involved in the reaction are diverse and control many elementary reactions. Expressed as a general reaction, it can be said that the composting reaction is organic material + oxygen = compost + carbon dioxide gas + water + ammonia. In addition to oxygen, environmental factors such as water content, temperature, and pH of the treatment material greatly affect the growth and physiological activity of microorganisms, and as a result of the fermentation reaction, these factors are affected in various ways. The present inventors have returned to the origin of this composting, and as a result of diligent research, have completed the present invention capable of high-speed fermentation treatment including composting and volume reduction.

That is, according to the method for fermenting an organic material of the present invention, the aerobic fermentation is performed by frequently stirring the organic material while maintaining the water content of the organic material in an appropriate range under a temperature-controlled air supply environment. It is characterized by

Further, the temperature of the air supply environment can be adjusted by supplying heated air whose temperature is adjusted as shown in the second aspect of the invention, and as shown in the third aspect of the invention, the organic material is It is also possible to do this by heating the contained fermenter. These may be performed alone or in combination. The temperature of the air supply environment is, as shown in the fourth invention,
It is desirable to adjust the temperature to 35 to 80 ° C. The air supply is
It is also possible to perform from the bottom of the fermenter as in the past,
Alternatively, the air may be blown directly into the atmosphere. When the air is blown directly into the atmosphere, it is possible to combine it with air diffusion or air supply from the bottom, in addition to performing it alone. The water content in the proper range of the organic treatment material is the fifth
As stated in the above invention, 30 to 60% is desirable. Maintaining the water content is achieved by sprinkling (preferably spraying) the organic material, but it can also be done by a humidified air supply in addition to or in combination with sprinkling.

Further, the fermentation treatment apparatus of the present invention comprises a closed type fermenter, an agitator provided in the fermenter, and an air supply device for adjusting the temperature and air volume of the air supplied to the fermenter. The apparatus is characterized by having an apparatus, an exhaust apparatus equipped with a deodorizing apparatus for exhausting gas from the inside of the fermentation tank, and a water sprinkling apparatus equipped with an apparatus for adjusting the temperature and flow rate of water sprayed into the fermentation tank. The closed type fermenter preferably has a good heat retaining property, and is preferably made of a material having a good heat retaining property or attached with a heat insulating material. As the stirring device,
Although a scoop type stirring device can be exemplified, the scoop type stirring device is not limited to this, and any paddle type, drum type, rotary kiln type or the like can be used. Further, the air supply device can be connected to the bottom surface of the fermenter by piping, and in addition, the air supply device can be provided so as to directly blow air into the space of the fermenter. In this case, it is possible to connect an air diffuser or an air supply device to the bottom surface of the fermenter together, and it is also possible to equip the bottom air supply device with a device for adjusting the temperature and the air volume. . As the sprinkler, it is desirable to spray water.

[0010]

In other words, according to the fermentation treatment method of the present invention, by frequently agitating the organic material,
The contact between the organic material and air is made efficiently. Furthermore, since the organic material is placed in a temperature-controlled air supply environment, the temperature drop of the organic material is prevented, the organic material is kept at an appropriate temperature, and the water content is maintained in an appropriate range. Fermentation can be carried out while maintaining the maximum speed, and fermentation processing can be performed at high speed.

Further, according to the fermentation treatment apparatus of the present invention,
It is possible to supply air to the fermenter at an appropriate temperature and air volume.
Moreover, since the fermenter has a closed structure, the fermenter can be stably maintained at a desired temperature and the influence of fluctuations due to seasons and weather can be reduced. Then, since the water can be sprinkled while adjusting the flow rate by the sprinkler, the organic material can be easily maintained at an appropriate water content. In addition, the temperature of the water sprinkling can be controlled, and it is possible to prevent the temperature of the organic material from fluctuating and adversely affecting the fermentation.

The present invention is not limited to high speed composting and volume reduction. Odorless fermentation is one of the strongest demands in the world as well as high-speed fermentation. The generation of odor during fermentation becomes remarkable when the temperature of the treated material is 60 ° C. or higher, and thus it is necessary to ferment at a temperature lower than this. Since the fermentation environment can be controlled in the present invention, low odor fermentation is possible. The operation of aeration and agitation is called primary fermentation in the fermentation process, and it is usually left to stand at room temperature for a similar period of time to perform a so-called aging process. In the process called secondary fermentation, the hardly decomposable organic matter remaining in the primary fermentation is fermented over time. Therefore, the material fermented in the present invention can be further secondarily fermented.

Next, the fermentation conditions and the like will be described more specifically. (1) Fermentation proceeds most efficiently by controlling the temperature of the air supply environment to 35 to 80 ° C. Then, by maintaining the temperature of the treated material at 35 to 80 ° C., preferably 45 to 70 ° C. until the reaction rate of fermentation is 80%, the fermentation reaction can be carried out while maintaining the fermentation reaction rate at the maximum. (2) The reason why the water content of the treated material is maintained at 30 to 60% is to allow the fermentation to proceed satisfactorily as in the case of adjusting the temperature. Suitably, the water content of the treated material is maintained at 30 to 60%, preferably 50 to 60% until the reaction rate of fermentation is 80%, and then gradually decreased to reduce the water content of the treated material at the end of the reaction. It is desirable to maintain 30 to 50%. (3) The stirring can efficiently bring the organic material into contact with air by stirring at intervals of 10 minutes to 12 hours. If the interval exceeds 12 hours, the action is not sufficient, and even if the mixture is stirred for less than 10 minutes, the effect is saturated and the work becomes troublesome. Therefore, the above range is preferable. (4) Furthermore, it is preferable that the organic material of the present invention is preferably pulverized by pretreatment so as to have an average particle size or average length of 1 to 20 mm. Further, it is desirable that the water content of the organic material at the start of treatment is 55 to 70%.

[0014]

EXAMPLE First, the fermentation treatment apparatus of the present invention will be described with reference to FIG. The horizontal linear groove type fermenter 1 is installed horizontally, and on the side wall of the fermenter 1, a scoop-type turning device 20 in which a scoop device 20a is hung is arranged, and the scoop-type turning device 20 is It is configured to reciprocate in the lengthwise direction of the fermenter 1 by a drive device (not shown). Further, the scoop device 20a is configured so that the inclination direction and the rotation direction of the scoop can be switched. Further, a cover 2 composed of both side walls, a top plate and a bottom plate is arranged around the fermentation tank 1 so as to cover the entire fermentation tank 1, and the fermentation tank 1 is of a hermetic type. The cover 2
A charging port 5 for charging the organic material 4 carried by the conveyor 3 is provided at the upper part of the rear end (left side of FIG. 1), while the processing part is provided at the bottom part of the front end side (right side of FIG. 1) of the cover 2. A discharge port 6 for discharging the used organic material is formed, and a discharge screw feeder 7 is installed below the discharge port 6.

The cover 2 has an air supply port 9 formed on the rear side wall and an exhaust port 10 formed on the front end side top plate. The air supply port 9 is provided with a temperature and an air volume through a valve 9a. An air supply device 9b capable of adjusting is connected. On the other hand, exhaust port 1
A deodorization / exhaust device 10a is connected to 0. Further, a plurality of spray nozzles 11 are attached to the top plate of the cover 2 so as to spray downward, and each spray nozzle 1
1 ... 11 are piping and valves 12a ... 12a, 12b
The spraying device is configured by being connected to the spraying device 12 capable of adjusting the temperature and the flow rate via. Also, fermenter 1
The bottom part of is formed of a perforated plate, and an air chamber 13 is provided below it, and this air chamber 13 is connected to a ventilation device 13b via a valve 13a. Although not shown, it is also possible to drain water from the bottom of the fermenter 1, and this discharged water (dirty water) can be used in the spraying device 12.

Next, the processing method of the present invention will be described according to the operation of the above apparatus. The organic material 4 whose water content and particle size have been adjusted is carried into the fermenter 1 from the charging port 5 by the conveyor 3. In the fermentation tank 1, heated air whose temperature is adjusted is continuously or intermittently supplied from the air supply device 9b through the air supply port 9 at a predetermined air volume, and the temperature in the fermentation tank 1 is within a predetermined range. It is maintained at (35 to 80 ° C).
Further, in conjunction with this, the ventilation device 13b can be operated to ventilate the bottom of the fermenter 1 through the air chamber 13. Furthermore, when the temperature in the fermenter 1 is sufficiently high or when it is desired to lower the temperature, the air supply device 9b is stopped,
It is also possible to operate only the ventilation device 13b.

The organic material 4 charged in the fermenter 1
In contrast, while moving the scoop type turning device 20, the inclined scoop device 20a is agitated and transferred.
During this stirring, the inclination of the scoop device 20a and the rotating direction of the scoop are appropriately switched, whereby the movement of the organic material 4 can be suppressed and the stirring can be frequently performed 10 to 15 times a day. is there. Further, the water content of the organic material 4 in the fermenter 1 is appropriately examined at different positions (with respect to the longitudinal direction), and the valves 12a ... 12a of the spray nozzles 11 ... 11 are adjusted based on the results, respectively. Water content of organic material 4 at each position is 30 to 60%
Adjust so that The water used for sprinkling is heated to 60 ° C. by the spray device 12. Further, during the fermentation process, the inside of the fermenter 1 is almost sealed, and the air inside is sucked from the exhaust port 10 and processed by the deodorizing / exhausting device 10a, so that the odor leaks to the surroundings of the device. Is reliably prevented. By repeating the above-mentioned operation, the organic material which has been stored for 20 days in the fermenter is discharged from the discharge port 6. The resulting treated material is secondary fermented (fermentation progress 80%
Above). In the conventional example in which the treatment is performed for the same number of days, the primary fermentation is performed (about 40%), and the treated material of the present invention undergoes fermentation twice or more as compared with the conventional material. Further, in the present invention, fermentation is progressing uniformly throughout the material.

Next, in order to confirm the effect of the present invention, a test for comparison with the conventional example was conducted. Fermentation treatment was carried out by using the kitchen waste, municipal solid waste, cattle manure and pig manure shown in Table 1 as organic raw materials according to the method of the present invention using the apparatus of the above-mentioned example and the conventional method using the conventional scoop type fermenter. The progress of fermentation after 20 days was compared and examined. The degree of progress of fermentation was determined by a method of determining the amount of the treated material by fermentation as a standard, and determining that the progress of fermentation was 100% when the reduction was almost stopped. Weight changes exclude changes in water content. The test results are shown in Table 1. It was confirmed that the organic material treated by the method of the present invention has progressed in fermentation and improved fermentation efficiency as compared with that of the comparative method. In addition, the organic material produced by the method of the present invention was fermented substantially uniformly, but the organic material produced by the comparative method had large variations.

[0019]

[Table 1]

[0020]

As described above, according to the fermentation processing method and apparatus of the present invention, the organic material is allowed to proceed with the reaction in a uniform and optimal environment while maintaining the maximum fermentation reaction rate. Therefore, composting and volume reduction can be performed at high speed.

[Brief description of drawings]

FIG. 1 is a schematic front view of an embodiment of the present invention.

[Explanation of symbols]

1 Fermenter 2 Cover 4 Organic material 5 Input port 6 Discharge port 9 Air supply port 10 Exhaust port 9b Air supply device 10a Deodorization / exhaust device 11 Spray nozzle 12 Spray device 20 Scoop type turning device 20a Scoop device

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Reference number within the agency FI Technical display location C05F 7/00 9/02 H 7537-4H (72) Inventor Yuichi Yoshino 1-chome, Takanodai, Yotsukaido-shi, Chiba No. 3 Stock Company Japan Steel Works (72) Inventor Masakazu Yokota 1-1-6 Funakoshi Minami, Aki-ku, Hiroshima City, Hiroshima Prefecture Hiroshima Steel Works (72) Inventor Koji Yoshimoto 1 Funakoshi-minami, Aki-ku, Hiroshima City, Hiroshima Prefecture 6th-1st Japan Steel Works, Ltd.

Claims (6)

[Claims] 1. A fermentation treatment of an organic material, which is characterized by frequently agitating the organic material to aerobically ferment it while maintaining the water content of the organic material in an appropriate range in a temperature-controlled air supply environment. Method 2. The temperature control of the air supply environment is performed by air supply of heated air whose temperature is adjusted.
Fermentation treatment method of the described organic material 3. The method for fermenting an organic material according to claim 1, wherein the temperature of the air supply environment is adjusted by heating a fermenter containing the organic material. 4. The method for fermenting an organic material according to claim 1, wherein the temperature of the air supply environment is adjusted to 35 to 80 ° C. 5. The method for fermenting an organic material according to claim 1, wherein the water content of the organic material is maintained at 30 to 60%. 6. A hermetically sealed fermenter, an agitator provided in the fermenter, an air supply device equipped with a device for adjusting the temperature and the amount of air supplied to the fermenter, and from the inside of the fermenter. A fermentation treatment apparatus comprising: an exhaust device equipped with a deodorizing device for exhausting gas, and a water sprinkling device equipped with a device for adjusting the temperature and flow rate of water sprayed in the fermentation tank.