JPH09100188A - Compost-making treatment of organic solid waste - Google Patents

Abstract

PROBLEM TO BE SOLVED: To carry out a fermentation treatment in a speedy and efficient manner by combining a storing treatment, a dehydration treatment, a storing process for separated sewage and a fermentation process, and spraying the sewage separated by the dehydration process on solid material during fermentation to lower the water content of the sewage nearly to a level suitable for fermentation in advance. SOLUTION: This treatment comprises a storing treatment process (A) receiving organic solid wastes (J) represented by garbage after crushed or as it is and storing them under facultative anaerobic conditions, a dehydration process (B) removing water from the organic solid wastes (J) to the water content of <=70% and separating them into a solid material (H) and separated sewage, a separated sewage-storing process (C) storing the sewage separated by the dehydration, and a fermentation treatment process (D) subjecting the solid material (H) prepared by dehydration to a fermentation treatment under aerobic conditions. In the fermentation process (D), the separated sewage stored in the separated sewage-storing process (C) is sprayed on the solid material (H) in order to keep the water content of the solid material (H) during fermentation at a level suitable for fermentation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composting method for aerobically fermenting an organic solid waste typified by raw garbage and recovering it as a soil conditioner or an organic fertilizer.

[0002]

2. Description of the Related Art In the composting process of organic solid waste with high water content (75 to 90%) such as raw garbage, it is usually crushed and then fermented as it is, sawdust, chips and the like are added and adjusted. Various methods such as fermentation treatment, drying, reduction of water content to perform fermentation treatment, product compost being returned and added to raw materials for adjustment and fermentation treatment are applied.

However, such conventional composting treatment methods generally have the following technical problems and are not in widespread use. (1) When raw garbage is crushed and subjected to fermentation treatment as it is, mudification, thickening, consolidation and the like occur at the early stage of fermentation. Therefore, air permeability becomes poor, aerobic fermentation processing becomes difficult, and fermentation processing requires a long period of 40 days or more. Further, since the anaerobic fermentation proceeds, the generated odor becomes strong, and the odor treatment becomes troublesome. Furthermore, a large amount of sewage is generated during the fermentation treatment process and the like, and a separate treatment facility is required, resulting in a large amount of cost.

(2) When adjusting the water content of raw garbage by adding an adjusting material such as sawdust and chips, in order to maintain the water content of raw garbage at an appropriate value for fermentation, a large amount of the adjusting material is used. Therefore, it is difficult to secure the required amount, the amount of treatment increases, the fermentation tank becomes large in size, and high cost is required. In addition, these conditioning materials require a long period of several months for fermentation and decomposition, and may also contain components that cause crop damage, so they are not effective treatment methods.

(3) When the water content is reduced by subjecting raw garbage to a drying treatment, equipment and energy for drying are required, resulting in a high cost. (4) When the product compost is returned and mixed with raw garbage and the water content of raw garbage is adjusted for fermentation treatment, the water content of raw garbage is greatly affected, and the water content is at most 75%. It is applicable in some cases, and beyond that, it is practically difficult to adjust. Further, the amount of the returned product used becomes too large, the equipment required for fermentation and the like becomes large and expensive.

Therefore, there is a method in which raw garbage is dehydrated in advance and fermented in a state where the water content is lowered, in Japanese Patent Publication No. 64-1.
No. 438. This is because organic solid waste (raw garbage) is cut into a size of about 5 to 20 mm, the cut piece is subjected to anaerobic fermentation, and the bound water is dissociated from the inside of the cut piece. This is a method for dehydrating organic solid waste by mechanically dehydrating it. Then, the dehydrated organic solid waste is put into a fermenter and aerobically fermented to be composted.

However, according to the method of performing the fermentation treatment in such a state that the organic solid waste is dehydrated and the water content is reduced, the water content is reduced to about 70% or less, which is close to an appropriate value for fermentation. However, it does not suggest performing a highly efficient and highly degradable fermentation treatment on the solid material in the fermentation treatment step after the dehydration treatment. In addition, a large amount of muddy separated sewage accompanying dewatering is difficult to handle, and is separately treated, which requires extra equipment and cost.

The present invention does not use raw materials having a high water content such as sawdust and chips, does not use complicated and expensive equipment for drying treatment, and does not use a large amount of energy. No return products,
Satisfying conditions such as not requiring separate treatment of wastewater generated in the dehydration treatment step, and prior to the fermentation treatment, the water content is stably reduced to about 70% or less, which is close to an appropriate value for fermentation, and then at a high speed. It is intended to be highly fermented.

[0009]

SUMMARY OF THE INVENTION The present invention has been made in view of such a conventional technical problem.
It is as follows. According to the invention of claim 1, a storage treatment step A in which an organic solid waste J typified by raw garbage is received in a crushed state or as it is and stored under a facultatively anaerobic condition, and then an organic solid waste is stored. Dehydration treatment of substance J to a water content of 70% or less to separate into solid material H and separated wastewater, dehydration treatment step B, separated wastewater storage step C for storing separated wastewater accompanying dehydration, and solid material after dehydration A fermentation treatment step D for fermenting H under aerobic conditions, wherein in the fermentation treatment step D, the water content of the solid material H during fermentation is maintained at an appropriate value for fermentation. In the method for composting organic solid waste, the separated sewage stored in the separated sewage storage step C is sprinkled on the solid material H during fermentation. According to claim 2, in the fermentation treatment step D, the total amount of the separated wastewater stored in the separated wastewater storage step C so that the water content of the solid material H during fermentation is maintained near the upper limit value for proper fermentation. 2. The method for composting organic solid waste according to claim 1, wherein the solid material H being fermented is appropriately watered.

[0010]

According to the invention of claim 1, after the organic solid waste J typified by raw garbage is crushed or left as it is, it is stored under facultative anaerobic conditions (1 to 3 days). , A dehydration process is performed, and the solid material H and separated wastewater are separated. According to this, even if the raw material has a high water content (about 80%),
Since the cells constituting the organism in the solid material H are decomposed and destroyed by the storage treatment step A, the water content of the solid material H separated by the subsequent dehydration treatment step B is appropriate for fermentation. It decreases to a value close to the value (70% or less). On the other hand, by this dehydration treatment step B, highly concentrated separated sewage containing 3 to 8% of organic suspended solids is obtained as separated sewage in an amount substantially equal to that of the solid material H after dehydration.

The solid material H whose water content has been reduced to a value close to an appropriate value for fermentation by the dehydration treatment step B is subjected to fermentation treatment. The solid material H in the fermentation treatment step D is an organic substance contained in a few days, which is heated to 50 to 60 ° C. in one day by aeration and intermittent or continuous mechanical stirring operation. Fermentative decomposition is accelerated, and the heat of fermentation and aeration as a medium promote evaporation and dissipation of water, and the water content of the solid material H is greatly reduced. When the water content of the solid material H decreases to 40 to 50%, the decomposition rate of organic substances in the fermentation process becomes slow. Therefore, when the water content is appropriately reduced, the high-concentration separated wastewater obtained in the dehydration treatment step B is sprinkled on the solid material H and mixed and homogenized by a stirring operation, and the water content is adjusted to an appropriate value for fermentation. Adjust to maintain. Thereby, the fermentation treatment of the solid material H
Fast and sophisticated. The high-concentration separated sewage obtained in the above dehydration treatment step B generally contains 3 to 3 organic suspended solids.
Although it contains 8%, most of the organic matter is fermented during the fermentation process.

According to the second aspect of the invention, the total amount of the separated wastewater stored in the separated wastewater storage step is maintained so that the water content of the solid material H during fermentation is maintained near the upper limit value for proper fermentation. The organic solid waste can be fermented at high speed without generating any sewage by appropriately sprinkling water on the solid material H during fermentation.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an apparatus used in a method for composting organic solid waste according to an embodiment of the present invention. The organic solid waste J typified by raw garbage is crushed by the crusher 1 to a particle size of 5 to 20 mm, if necessary. This organic solid waste J is supplied to the pretreatment storage tank 2 via the conveyor 10 and is aerated in the pretreatment storage tank 2 under aeration and gentle agitation for 1 to 3 days under a facultatively anaerobic condition. The storage process below is performed. This is,
This is the storage processing step A.

Next, the organic solid waste J is sent to a screw press type dehydrator 3 and separated into a solid material H and a muddy wastewater. This is the dehydration treatment step B, and the organic solid waste J having a high water content (75 to 90%) is dehydrated to the solid material H having a water content of 70% or less.
In addition to the screw press, a dehydrator such as a filter press, a belt press, a centrifuge, a vacuum filter, or the like can be applied to the dehydration treatment step B. However, the organic solid waste J has a muddy shape and shape. When qualitative variations are large, it is preferable to use a screw press from the viewpoint of ensuring continuous and stable processing performance and low cost.

According to the method in which the organic solid waste J is stored for 1 to 3 days under a permeable anaerobic condition and then dehydrated, vegetables, fruits and fish contained in the organic solid waste J are treated. The cells constituting the organism such as meat are decomposed and destroyed by the facultative anaerobic fermentation treatment, and the internal bound water is dissociated and easily flows out to the surface, and the solid material H is produced by the dehydration treatment. The water content of 65 is close to 90%
It can be reduced to ~ 70%.

In the above dehydration treatment step B, the solid material H and the sludge-like wastewater are separated so that highly concentrated separated wastewater containing 3 to 8% of organic suspended solids is dehydrated solid material H. It occurs in the same amount as. For example, a predetermined amount of organic solid waste J is 288 kg of solid material having a water content of about 69%.
Per day and 212 kg / day of mud-like sewage containing 5% of organic suspension (including 11 kg / day of organic suspension). This separated sewage is caused to flow out from the sewage outlet 3b of the dehydrator 3 and stored in the sewage receiving tank 5. This is the separated sewage storage step C for storing the separated sewage.

On the other hand, the solid material H after dehydration is sent to the fermenter 4. That is, the outlet 3a of the dehydrator 3
A discharge feeder (not shown) is attached in the vicinity, and the solid material H is quantitatively discharged from the discharge port 3a by this discharge feeder. Solid material H discharged from the discharge port 3a
Is sent to the fermenter 4 via the conveyor 11 and fermented in the fermenter 4 under aerobic conditions. This is a fermentation treatment step D in which the dehydrated solid material H is subjected to fermentation treatment.

Here, the fermenter 4 will be described. The fermentation device 4 has a scoop-type stirring device 15 inside the hermetically-sealed fermenter 4a, and the solid material H charged from the charging port 4e to one end of the fermenter 4a is in the longitudinal direction. Intermittent (or continuous) stirring and mixing by the movable stirring device 15 is repeated, and the mixture is gradually transferred to the discharge part 4c at the other end while undergoing fermentation treatment under aerobic conditions. During that time, a predetermined amount of aeration and water sprinkling are performed on the solid material H.

[0019] That is, the placing porous plate 4b by partitioning the air passage 4d (4d ₁ ~4d ₅₎ between the bottom of the fermenter 4a, Yotsute the air passage 4d into a plurality of Sakaikabe 4f Dividing in the longitudinal direction, the first to fifth ventilation paths 4d _{1 to} 4d
_{There is as 5} . The first to fifth ventilation passages 4d _{1 to} 4d ₅ are connected to one supply line 4g via branch lines respectively interposing the flow meter 13 and the flow rate adjusting valve 21, and ventilation is provided at the end of the supply line 4g. The blower 8 is connected. Then, the air sent from the ventilation blower 8 to the supply line 4g is heated to a predetermined temperature by the ventilation heater 17 and then adjusted to a predetermined opening degree based on the detection value of each flow meter 13. through connexion the flow control valve 21, fed to the individual to the first to fifth air passage 4d ₁ ~4d _5, is appropriately vented perforated plate 4b on through connexion above the solid material H. The heating temperature by the ventilation heater 17 is set to a temperature suitable for fermentation based on the temperature of the solid material H measured by the measuring instrument 16 which measures the temperature and the water content, respectively.
In this way, a predetermined amount of aeration is provided for each zone in the fermentation tank 4a in the longitudinal direction, and fermentation processing is performed under aerobic conditions. The ventilation blower 8, the supply line 4g, the ventilation heater 17, each flow rate adjusting valve 21, each flow meter 13, and the ventilation path 4d.
A ventilation device is constituted by the above.

Further, in the space above the solid material H in the fermenter 4a, a nozzle 14 (in the illustrated example, a discharge part in the example shown) equipped with a flow rate adjusting valve 22 is provided for each predetermined area in the longitudinal direction of the fermenter 4a. (3 in total) is provided for each predetermined area near 4c. Then, the separated sewage stored in the sewage receiving tank 5 is driven by the sewage pump 25 installed in the sewage receiving tank 5 to adjust the flow rate adjusting valve 23 to a predetermined opening degree.
Through the nozzles 14, and the water is sprayed from each nozzle 14 in a predetermined amount set by each flow rate adjusting valve 22. The total flow rate of the separated sewage flowing out of the sewage receiving tank 5 is detected by the flow rate integrator 20. The waste water receiving tank 5, the waste water pump 25, the flow rate integrator 20, the flow rate adjusting valve 23, each flow rate adjusting valve 22, and each nozzle 14 constitute a sprinkler.

[0021] Generally, in the case of organic solid waste J which is a well-sorted domestic garbage containing a large amount of vegetables and having a water content of about 80%, the solid material after dehydration through the dehydration treatment step B is carried out. Since the water content of H is 70% or less, normally, without being crushed by the crusher 1, the solid material H after dehydration through the separation wastewater storage step C is directly fed to the fermentation tank 4a for fermentation. To process. Fermenter 4a solid material H which has been put into from first to fifth air passage 4d ₁ ~4d ₅ of the venting device, proper temperature and proper amount (e.g., material 1t per 100
Aeration of up to 500 l / min) and stirring device 1
By intermittent (or continuous) mechanical stirring operation by 5,
After one day, the temperature is raised to 50 to 60 ° C., and the fermentation decomposition of the organic matter contained in the solution is accelerated in a few days. Due to this fermentation heat and aeration as a medium, water vaporization proceeds and the water content of the solid material H increases. The rate will drop significantly.

It is known that when the water content of the solid material H decreases to 40 to 50%, the decomposition rate of organic substances in the fermentation process becomes slow. To avoid this, the temperature and solid state in the fermenter 4a should be reduced. The water content of the material H and the water content of the material H are tracked by the measuring device 16. Then, when the water content falls to about 50%, the high-concentration separated sewage obtained in the dehydration treatment step B is sprinkled by the sprinkler, and the solid material H is stirred by the stirrer 15. And separated sewage are mixed and homogenized, and the water content is appropriate for fermentation (about 55-60%)
Adjust so that The stirrer 15 uses the solid material H
It also has the function of improving the efficiency of contact between the and aeration, and promotes and stabilizes fermentation decomposition.

According to the actual measurement, the high-concentration separated sewage obtained in the above-mentioned dehydration treatment step B contains 3 to 8% of organic suspended matter, and the BOD is also tens of thousands of pp.
m is included, and when this is purified by an activated sludge treatment method or the like, not only a treatment device is required but also a great treatment cost is required. If the separated sewage accompanying this dehydration is sprinkled on the fermentation material (solid material H) in the fermentation processing step D, most of the organic suspended matter contained in a considerable amount is fermented as organic matter. Therefore, not only the separated wastewater is treated, but also fermentation is promoted, which is convenient. Then, the separated sewage stored in the separated sewage storage step C is appropriately sprinkled onto the solid material H being fermented so that the water content of the solid material H being fermented is appropriate. It is desirable to keep the amount of the separated sewage in the vicinity of the upper limit value for the purpose and to appropriately sprinkle the entire amount of the separated wastewater on the solid material H during fermentation.

The solid material H which has undergone the fermentation process is discharged from the discharge section 4c of the fermentation tank 4a, transferred through the conveyor 12 and stored in the product storage tank 6 for recovery and utilization as product compost. The odor generated in the fermenter 4a is
It is sucked and collected by the deodorizing blower 9, deodorized and purified by the microbial decomposition type deodorizing device 7 to a value not more than the legally regulated value, and then released to the atmosphere.

The points of the method for composting the organic solid waste are as follows. That is, by starting the dewatering process of raw garbage having a high water content to an appropriate water content, the start-up of fermentation for the solid material H is early, and a good fermentation process is started early.
The fermentation decomposition is activated, and the temperature rising state is maintained. And
When the water content decreases, the separated wastewater is appropriately sprinkled, and the complete fermentation treatment is performed while adjusting the water content to an appropriate range. Then, in the fermentation treatment step D, a mechanical agitation system by the agitation device 15 is applied to separate separated wastewater and solid material H
And homogenization of the mixture, and the efficiency of contact between the solid material H and aeration are promoted to promote and stabilize the fermentation decomposition. The air from the blower 18 shown in FIG. 1 is heated by the ventilation heater 19 to a predetermined temperature in consideration of the outside air temperature, and the ventilation passage 4
By aeration from the h on the surface of the solid material H in the fermenter, condensation of evaporated water from the solid material H is prevented and the evaporation effect of water is enhanced.

[0026]

Example: Actually, 500 kg of garbage having a water content of 80%
/ Day was fermented. First, the organic solid waste J is crushed by the crusher 1 to a particle size of 5 to 20 mm and supplied to the pretreatment storage tank 2, and the pretreatment storage tank 2 is aerated without aeration and under a gentle stirring operation. Storage treatment was performed under facultative and anaerobic conditions for about 3 days. Then, this organic solid waste J
To a screw press type dehydrator 3, and the water content is about 69.
% Solid material 288 kg / day and organic suspended matter 5% mud-like wastewater 212 kg / day (of which organic suspended matter 11 kg
/ Day) and separated. The separated sewage was stored in the sewage receiving tank 5.

On the other hand, the solid material H after dehydration is the fermenter 4
sent to a. Then, the process proceeds to the fermentation process step D, the condition of the fermentation temperature is confirmed by the measuring meter 16, and accordingly, the flow rate of the aeration blower 8 through the supply line 4 g and each flow meter 13 is 100 to 500 l / min per 1 t of the material. Aeration was performed in a controlled range, and fermentation was performed for 20 days. The situation in this fermentation process is shown in FIGS. The solid material H (indicated by S in FIG. 2) charged to the fermenter 4a is heated to about 60 ° C. as shown in FIG. 4 in 1 to 2 days after charging, and is charged at the time of about 5 days. As shown in FIG. 2, the organic matter (loss on ignition) contained in the solid material H is decomposed by α _a : about 28% (ratio to the total organic matter in raw raw garbage), and the bottom surface of the fermenter 4a is decomposed by the heat of decomposition. The moisture in the solid material H was volatilized by 132 kg in the last 5 days through the ventilation from
It decreased to 0% (point a in FIG. 2). In this case, in order to enhance the volatilization effect of water, it is possible to increase the amount of aeration supplied from the blower 18 onto the surface of the solid material H in the fermenter 4a.

At this time, the separated sewage in the sewage receiving tank 5 is pumped up by the sewage pump 25, the supply amount of the separated sewage is confirmed by the flow rate integrator 20, and the water content of the solid material H is measured by the meter 16
While checking the above, water is added to the solid material H via each nozzle 14 and mixed by stirring with a stirring device 15, and as a result, 38 kg / day of separated sewage is added, and the solid material H is hydrated. The rate was adjusted to about 60% (a 'in Fig. 2
point). The stirrer 15 has a structure that can be moved forward and backward, and the solid material H and separated wastewater are mixed and homogenized by a stirring operation.

Further, after about 2 days, as shown in FIG. 2, the organic matter is decomposed by α _b : about 8.5%, and the heat of decomposition and aeration vaporize 41 kg / day of water in the solid material H. ,
The water content decreased to about 50% (point b in FIG. 2). At this point, the separated sewage in the sewage receiving tank 5 was sprinkled again at a rate of about 35 kg / day in the same manner as described above to adjust the water content to about 60% (point b'shown in FIG. 2), and continuously fermented. . Sequentially, cc ', dd', ee ', f- shown in FIG.
f ', g-g', h-h 'and reduction of evaporation of water in the solid material H by fermentation decomposition and adjustment of sprinkling of separated separated waste water are repeated, and total separated separated waste water obtained in the dehydration treatment step B as a whole. About 221 kg / day of the separated sewage, which is almost equivalent to the amount, was sprinkled. Therefore, the total amount of the total amount of separated wastewater (212 kg / day) obtained in the dehydration treatment step B can be appropriately sprayed on the solid material H during fermentation.

In this manner, the fermentation operation was carried out for about 20 days, and the decomposition of organic matter (individually indicated by α _{a to} α _h and α _E in FIG. 2) was better than the conventional one. As shown in 3, cumulatively about 80% of organic matter is decomposed, and
With the final water content of about 40% ((indicated by E in FIG. 2), a compost applicable to ordinary crops was obtained. Also, the temperature and pH of the solid material H in the fermenter 4a in this fermentation treatment were high. In any of the above, as can be seen from FIG. 4, the method of the present invention indicated by black circles and black triangles has a better start-up than the conventional methods indicated by white circles and white triangles, and thereafter,
It was confirmed that the fermentation process was performed at high speed and with good efficiency.

By the way, in the above embodiment, in order to make the water content of the solid material H during fermentation close to the upper limit value for proper fermentation, the water content of the solid material H is about 60%. When the water content decreased to about 50%, the separated wastewater in the wastewater receiving tank 5 was sprinkled, but when the water content slightly decreased, the separated wastewater was sprinkled in a timely manner to constantly It is also possible to maintain the water content of the solid material H near the upper limit value for proper fermentation. Even in that case, the entire amount of the separated wastewater stored in the separated wastewater storage step C is appropriately sprinkled on the solid material H during fermentation.

[0032]

As will be understood from the above description,
According to the method for composting organic solid waste according to the present invention, the following effects can be achieved. (1) Organic solid waste consisting of garbage with a high water content (80% or more), which conventionally required 40 days or more for fermentation treatment, is a stable, homogeneous, and high-quality product within 20 days of treatment. It becomes possible to use it as compost. Therefore, in the composting process of organic solid waste typified by raw garbage, it is possible to subject the solid material to highly efficient and highly decomposable fermentation treatment and recover it as a soil conditioner or organic fertilizer. Become.

(2) Conventionally, in the composting treatment of organic solid waste typified by raw garbage, it is difficult to treat high-concentration wastewater generated in the dehydration process, fermentation process, etc. Although it was separately processed by incineration or the like, which required a high cost, it is possible to perform a batch process by the fermentation process, and thus a low cost process is possible. That is, according to the method of the present invention, with the dehydration treatment, a large amount of separated sewage generated in a mud state is effectively utilized for adjusting the water content,
The cumbersome handling is saved, and the separate equipment and cost for treating the separated wastewater are reduced.

(3) In the fermentation treatment step, by appropriately spraying the separated sewage on the solid material, a favorable aerobic fermentation operation can always be performed, so that the generation of offensive odors such as organic acids and amines is suppressed. . As a result, the conventional combustion treatment method,
Compared with the chemical cleaning activated carbon method, ozone oxidation method, etc., it is possible to apply microbial decomposition type deodorization processing, which is generally considered to be cheap in terms of equipment costs, operating costs, etc.

(4) Since high-speed fermentation treatment of organic solid waste is possible, the fermentation apparatus is downsized, and separate treatment of separated wastewater is not required. Therefore, the overall structure is simple and the cost is low. Processing becomes possible. In particular, since the processing period of the fermenter is halved, when treating the same amount of organic solid waste, the fermenter is significantly downsized. In addition, the deodorizing device is also halved in scale. Thus, according to the method for composting organic solid waste according to the present invention, the pretreatment storage step for facultative anaerobic treatment and the subsequent dehydration treatment step are increased as compared with the conventional example. However, as a whole, the above-mentioned great practical effect is brought about.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing an apparatus for composting organic solid waste according to an embodiment of the present invention.

FIG. 2 is a diagram showing a water content-elapsed fermentation days characteristic.

FIG. 3 is a diagram similarly showing the organic matter decomposition rate-fermentation elapsed days characteristic.

FIG. 4 is a diagram showing fermentation temperature and pH-elapsed fermentation days characteristics.

[Explanation of symbols]

1: Crusher, 2: Pretreatment storage tank, 3: Dehydration device, 4: Fermentation device, 4a: Fermentation tank, 4d: Ventilation path, 6: Product storage tank, 7: Deodorization device, 8: Ventilation blower, 13: Flow meter, 1
4: Nozzle, 15: Stirrer, 16: Measuring meter, 17: Ventilation heating heater, 20: Flow rate integrating meter, 21: Flow rate adjusting valve,
22: Flow control valve, 25: Sewage pump, A: Storage treatment process, B: Dewatering treatment process, C: Separation wastewater storage process, D: Fermentation treatment process, H: Solid material, J: Organic solid waste.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Masakazu Yokota 1-6-1, Funakoshi-minami, Aki-ku, Hiroshima-shi, Hiroshima Prefecture Japan Steel Works, Ltd. (72) Takashi Otani 1-chome, Funakoshi-minami, Aki-ku, Hiroshima-shi, Hiroshima 6-1 Japan Steel Works, Ltd. (72) Inventor Kenji Fukushima 1-6-1, Funakoshi-minami, Aki-ku, Hiroshima-shi, Hiroshima Prefecture Japan Steel Works Co., Ltd. (72) Tatsuo Nagai Funakoshi-minami, Aki-ku, Hiroshima-shi, Hiroshima Prefecture 1-6-1, Japan Steel Works, Ltd. (72) Inventor, Koji Hattori 1-6-1, Funakoshi Minami, Aki-ku, Hiroshima City, Hiroshima Prefecture Hiroshima Prefecture (72) Inventor Akio Ohno, Aki-ku, Hiroshima City, Hiroshima Prefecture 1-6-1, Funakoshi Minami Inside Japan Steel Works, Ltd.

Claims (2)

[Claims] 1. A storage treatment step (A) in which an organic solid waste (J) typified by raw waste is crushed or received as it is and stored under facultative anaerobic conditions, and then an organic treatment. Dewatering treatment of solid waste (J) to a water content of 70% or less, separating into solid material (H) and separated wastewater (B), separated wastewater storage step of storing separated wastewater accompanying dehydration ( C) and a fermentation treatment step (D) of fermenting the dehydrated solid material (H) under aerobic conditions, wherein in the fermentation treatment step (D), the solid material (H during fermentation is )
The organic matter characterized in that the separated wastewater stored in the separated wastewater storage step (C) is sprinkled onto the solid material (H) during fermentation so that the water content of the separated wastewater maintains an appropriate value for fermentation. Method for composting solid waste. 2. The fermentation treatment step (D), in the separation wastewater storage step (C), so that the water content of the solid material (H) during fermentation is maintained near the upper limit value for proper fermentation. The method for composting organic solid waste according to claim 1, wherein the entire amount of the separated separated wastewater is appropriately sprinkled on the solid material (H) during fermentation.