JP7634266B2 - Waste treatment plant and waste treatment method - Google Patents

Description

The present invention relates to a waste treatment plant and a waste treatment method for utilizing waste generated in homes, restaurants, traditional Japanese restaurants, hotels, supermarkets, etc., which is a mixture of food waste, paper, plastic, etc., as a biomass resource, and in particular to a waste treatment plant and a waste treatment method that can reduce energy costs.

Most household waste generated by households, restaurants, hotels, supermarkets and other food and beverage service industries, schools and other business establishments is separated into several types and collected using methods designated by local governments. Organic waste such as raw vegetables, fruit, meat and other food waste is incinerated as combustible material together with other combustible waste at incineration sites.
However, in recent years, from the perspective of environmental load, efforts have been made to reduce the amount of food waste incinerated by reusing it as a resource. For example, methods such as fermenting and maturing food waste in an aerobic environment to turn it into compost and recycling it as organic fertilizer, and methane gasification (biogasification) by subjecting slurry-like food waste to methane fermentation in an anaerobic environment are known.

For example, Patent Document 1 proposes a food waste recycling method in which dried food waste such as food waste brought to a treatment facility is dissolved in dissolution water in a re-dissolution process to return it to liquid organic waste, and the liquid organic waste is then fermented into methane in a methane fermentation process to recover biogas.

JP 2003-245631 A

However, when converting waste into methane gas (biogasification), liquid organic waste is fermented into methane, which results in a large economic burden for the treatment of the large amount of slurry or liquid fermentation residue (also called digestate) that is generated.
For example, Patent Document 1 describes that the fermentation residue after methane fermentation is used as liquid fertilizer or composted and returned to agricultural land. However, when the plant is not close to a site environment such as a vast pasture or field where the liquid fertilizer can be spread and the liquid fertilizer is spread on land far away, a large energy cost and other expenses are incurred for transporting the fermentation residue, which has a high moisture content. In addition, in the case of a land environment where a large amount of fermentation residue cannot be applied, a large tank facility for storing the fermentation residue is also required. Furthermore, it is costly to take measures against odors when transporting or storing the fermentation residue. In addition, since such fermentation residue contains a large amount of phosphorus and nitrogen, it is also necessary to control and manage the amount of fertilizer to prevent soil and groundwater pollution.

On the other hand, in cases where there is no farmland in the vicinity where the fermentation residue can be used as liquid fertilizer, the fermentation residue may be separated into solids and liquids, and the dehydrated solids may be composted or incinerated. However, the liquid fraction of the fermentation residue and the liquid after dehydration contain a lot of organic matter, phosphorus, and nitrogen, so they cannot be directly discharged into sewers or rivers. This requires the installation of large-scale purification facilities (wastewater treatment facilities) for the wastewater, which results in high energy costs for purification.

The present invention aims to provide a waste treatment plant and method that can reduce energy costs and effectively use waste to produce biogas and resources.

The waste treatment plant of the invention of claim 1 is equipped with a pretreatment facility that separates waste into a high-moisture methane fermentation target material to be subjected to methane fermentation and a low-moisture selection residue, and prepares the methane fermentation target material into a slurry, a methane fermentation facility that performs methane fermentation on the slurry-like methane fermentation target material to produce biogas, a mixing section that mixes the slurry-like methane fermentation residue after the methane fermentation of the methane fermentation target material with the separated selection residue, and further adds a bulk density adjusting material and a microbial attachment body having aerobic microorganisms attached thereto to create an aerobically fermented target material to be subjected to aerobic fermentation, an aerobic fermentation drying facility that aerobically ferments and dries the aerobically fermented target material, and a posttreatment facility that selects solid fuel material and/or compost material from the aerobically fermented and dried target material after the aerobically fermented and dried target material.

The above pretreatment equipment breaks the bags that usually contain food waste, paper scraps, etc., from the collected waste, separates the waste to be subjected to methane fermentation treatment from the remaining residue, and prepares the waste to be subjected to methane fermentation treatment into a slurry. It is composed of, for example, a crusher, a sorting machine such as a crusher and sorter, a mixing/agitation tank, etc.

Here, the above separation can be performed based on, for example, particle size or weight (buoyancy), with a predetermined fraction of undersized heavy items being treated as high-moisture materials to be subjected to methane fermentation treatment, including a large amount of easily decomposable organic matter such as food waste, and a predetermined fraction of oversized light items being treated as low-moisture residues. Here, it is sufficient to separate mainly high-moisture materials such as food waste from the collected waste as materials to be subjected to methane fermentation treatment.
The above-mentioned humidity adjustment means that the material to be subjected to methane fermentation treatment is finely divided and homogenized by stirring or the like, and the material to be subjected to methane fermentation treatment is adjusted to a slurry state having a predetermined solid content suitable for methane fermentation.
The above-mentioned separation and conditioning are usually carried out by separate machines, but separation and conditioning may be carried out simultaneously.
The above waste materials include general household waste, which is burnable garbage such as food waste and paper scraps generated from homes and businesses, office waste, industrial waste such as food waste, animal and food residues, etc.

The methane fermentation equipment performs methane fermentation on the slurry-like methane fermentation target material to generate biogas, and is composed of, for example, a vertical or horizontal methane fermentation device (methane fermentation tank) with an airtight structure and equipped with stirring means, heating means, temperature control means, pumps, etc.

The mixing section mixes the slurry-like methane fermentation residue after the methane fermentation of the methane fermentation target with the separated selected residue, and further adds a bulk density adjusting material to increase the volume and a microbial attachment body to which aerobic microorganisms are attached to create an aerobic fermentation target to be subjected to aerobic fermentation. The raw materials may be mixed in a mixer, or it may be a work area where the raw materials are mixed uniformly using a wheel loader, shovel, etc.

The bulk density adjusting material may be anything capable of increasing the volume of the aerobically fermented material so that a certain amount of void space for ventilation can be formed in the pile of the aerobically fermented material. Preferably, a material having water absorption and hygroscopic properties and capable of supporting microorganisms, such as wood chips or a solid fuel obtained by converting a solid fuel raw material selected from aerobically fermented and dried material, can be used.
Furthermore, the microbial-attached material may be any material having aerobic microorganisms attached thereto that function as seed bacteria and promote aerobic fermentation of the aerobic fermentation-treated material; for example, a portion of the aerobic fermented and dried material after aerobic fermentation and drying may be used.
However, even if the bulk density adjuster is a wood chip or solid fuel, aerobic bacteria will adhere to it after aerobic fermentation and drying, so it also functions as a microbial adhesion body. Therefore, the addition of the bulk density adjuster and the microbial adhesion body does not necessarily need to be distinguished from each other, and they may be used together.

The aerobic fermentation and drying equipment aerobically ferments the aerobically fermented material and dries it using the heat of fermentation. Preferably, the progress of aerobic fermentation and drying of the aerobically fermented material is promoted by blowing air onto the aerobically fermented material. For example, the aerobic fermentation and drying equipment is configured with an airtight structure that is equipped with a fan (blower) and controls the introduction and exhaust of air.

The above-mentioned post-treatment equipment is used to remove non-combustible materials, for example, by magnetic sorting, and vinyl chloride, for example, by near-infrared sorting, from the aerobic fermentation and drying processed material, and to separate solid fuel raw materials or compost raw materials. It is composed of, for example, a magnetic sorting device, a near-infrared device, a particle size/weight sorting device, etc.

The waste treatment plant of the invention of claim 2 further includes a first circulating water facility that collects wastewater from the aerobic fermentation and drying facility where the aerobically fermented material is aerobically fermented, passes the wastewater through a filter that removes foreign matter mixed in the wastewater, and then sprays the aerobically fermented material in the aerobic fermentation and drying facility.

The first circulating water equipment collects wastewater from the aerobic fermentation and drying equipment, i.e., leachate seeping out from the aerobically fermented material undergoing aerobically fermenting in the aerobic fermentation and drying equipment and excess water from sprinkling, removes foreign matter contained therein using a filter, and then sprinkles the aerobically fermented material undergoing aerobically fermenting in the aerobic fermentation and drying equipment. For example, the equipment is composed of a circulation path that outputs wastewater from the aerobic fermentation equipment and returns it to the aerobic fermentation equipment, a filtration filter, a pump, a sprinkling device, etc.

The waste treatment plant of the invention of claim 3 further comprises a deodorizing system that biologically deodorizes the air discharged from the aerobic fermentation and drying system in which the aerobic fermentation material is aerobically fermented using a biofilter containing aerobic microorganisms and exhausts the air to the outside, and a second circulating water system that supplies moisture to the biofilter of the deodorizing system by sprinkling water, collects excess water from the sprinkling, and reuses it for sprinkling.

The deodorizing equipment is a device that decomposes and deodorizes the aerobic microorganisms contained in the biofilter by ventilating the air discharged from the fermentation and drying equipment in which the aerobically fermented material is aerobically fermented through a biofilter made of a carrier such as wood chips to which aerobic microorganisms are attached, or soil containing aerobic microorganisms, and is composed of, for example, a biological deodorizing device filled with a carrier such as wood chips to which aerobic microorganisms are attached, or soil.
In addition, the second circulating water equipment supplies moisture to the biofilter of the deodorizing equipment by sprinkling water, and collects excess water from the sprinkling and reuses it for the sprinkling, and is composed of, for example, a circulation path, a pump, a sprinkling device, etc. that outputs excess water from the deodorizing equipment and returns it to the deodorizing equipment.

The waste treatment plant of the invention of claim 4 further comprises an air plenum chamber into which air discharged from the aerobic fermentation drying equipment in which the aerobic fermentation treatment material is aerobically fermented is input, and which reduces the humidity of the air and outputs the air to the biological deodorization equipment.

The system includes an air plenum chamber into which air discharged from the aerobic fermentation and drying equipment in which the aerobically fermented material is aerobically fermented and air having a lower relative humidity than the air discharged from the aerobic fermentation and drying equipment are input and mixed, and the mixed air is output to the biological deodorization equipment.

The air plenum chamber has a predetermined volume, and receives the air discharged from the aerobic fermentation drying equipment, as well as air with a lower relative humidity than the air discharged from the aerobic fermentation drying equipment. The air discharged from the aerobic fermentation drying equipment and the air with a lower relative humidity than the air discharged from the aerobic fermentation drying equipment are mixed and conditioned to reduce the humidity of the air discharged from the aerobic fermentation drying equipment, and air with a lower relative humidity than the air discharged from the aerobic fermentation drying equipment is output to the biological deodorization equipment. Note that air with a lower relative humidity than the air discharged from the aerobic fermentation drying equipment does not necessarily have to always have a lower humidity than the air discharged from the aerobic fermentation drying equipment, but rather it is sufficient that the humidity of the highly humid air discharged from the aerobic fermentation drying equipment can be reduced in the air plenum chamber.

The waste treatment plant according to the present invention further comprises a cogeneration facility which refines the biogas and uses it as fuel to supply heat and electricity.
The cogeneration facility is, for example, composed of a gas engine generator, a steam boiler, a heat exchanger, etc., and generates electricity and heat by using the refined biogas as fuel. For example, the biogas may be used as fuel to generate electricity with a gas engine generator, and the waste heat generated at that time may be extracted as hot water or steam with a steam boiler or a heat exchanger, etc., and the hot water or steam may be used to heat or keep warm the methane fermentation facility.

The waste treatment method of the invention of claim 6 separates waste into a high-moisture methane fermentation-treated material to be subjected to methane fermentation and a low-moisture selection residue in a pretreatment process, prepares the methane fermentation-treated material into a slurry, and in a methane fermentation process, methane fermentation of the slurry methane fermentation-treated material is performed to generate biogas. In a mixing process, the slurry methane fermentation residue after the methane fermentation of the methane fermentation-treated material is mixed with the selected selection residue, and a bulk density adjusting material and a microbial attachment body having aerobic microorganisms attached thereto are added to prepare an aerobically fermented material to be subjected to aerobic fermentation. In an aerobic fermentation drying process, the aerobically fermented material is aerobically fermented and dried, and in a posttreatment process, a solid fuel material and/or compost material is selected from the aerobically fermented and dried aerobically fermented material after the aerobically fermented and dried aerobically fermented material.

The above pretreatment process involves breaking open the dust bags that typically contain food waste, paper scraps, etc., from the collected waste, separating the waste into methane fermentation material to be subjected to methane fermentation and the remaining sorting residue, and conditioning the methane fermentation material into a slurry-like material.

Here, the above separation can be performed based on, for example, particle size or weight (buoyancy), with a predetermined fraction of undersized heavy items being treated as high-moisture materials to be subjected to methane fermentation treatment, including a large amount of easily decomposable organic matter such as food waste, and a predetermined fraction of oversized light items being treated as low-moisture residues. Here, it is sufficient to separate mainly high-moisture materials such as food waste from the collected waste as materials to be subjected to methane fermentation treatment.
The above-mentioned humidity adjustment means that the material to be subjected to methane fermentation treatment is finely divided and homogenized by stirring or the like, and the material to be subjected to methane fermentation treatment is adjusted to a slurry state having a predetermined solid content suitable for methane fermentation.
The above-mentioned separation and conditioning are usually carried out by separate machines, but separation and conditioning may be carried out simultaneously.
The above waste materials include general household waste, which is burnable garbage such as food waste and paper scraps generated from homes and businesses, office waste, industrial waste such as food waste, animal and food residues, etc.

The methane fermentation process is a process in which the slurry-like methane fermentation target material is fermented to produce biogas.

The mixing process is a process in which the slurry-like methane fermentation residue after the methane fermentation of the methane fermentation target material is mixed with the separated selected residue, and a bulk density adjusting material for increasing the volume and a microbial attachment body having aerobic microorganisms attached thereto are added to prepare an aerobic fermentation target material to be subjected to aerobic fermentation.

The bulk density adjusting material may be anything capable of increasing the volume of the aerobically fermented material so that a certain amount of void space for ventilation can be formed in the pile of the aerobically fermented material. Preferably, a material having water absorption and hygroscopic properties and capable of supporting microorganisms, such as wood chips or a solid fuel obtained by converting a solid fuel raw material selected from aerobically fermented and dried material, can be used.
Furthermore, the microbial-attached material may be any material having aerobic microorganisms attached thereto that function as seed bacteria and promote aerobic fermentation of the aerobic fermentation-treated material; for example, a portion of the aerobic fermented and dried material after aerobic fermentation and drying may be used.
However, even if the bulk density adjuster is a wood chip or solid fuel, aerobic bacteria will adhere to it after aerobic fermentation and drying, so it also functions as a microbial adhesion body. Therefore, the addition of the bulk density adjuster and the microbial adhesion body does not necessarily need to be distinguished from each other, and they may be used together.

The aerobic fermentation and drying process involves aerobically fermenting the aerobically fermented material and drying it using the heat of fermentation. Preferably, the progress of aerobic fermentation and drying of the aerobically fermented material is promoted by blowing air onto the aerobically fermented material.

The post-processing process is, for example, a process of removing non-combustible materials by magnetic sorting, and vinyl chloride by near-infrared sorting, and separating the solid fuel raw materials and/or compost raw materials.

In the aerobic fermentation and drying process of the waste treatment method of the invention of claim 7, wastewater (leachate) seeping out from the aerobically fermented material undergoing aerobic fermentation is collected, filtered, and then sprayed onto the aerobically fermented material. In other words, the leachate seeping out from the aerobically fermented material undergoing aerobically fermentation and excess water from the spraying are collected, foreign matter contained therein is removed with a filter, and then the water is sprayed onto the aerobically fermented material undergoing aerobically fermentation.

The waste treatment method of the invention of claim 8 further includes a deodorization process in which the indoor air in which the aerobically fermented material is aerobically fermented is biologically deodorized by a biofilter containing aerobic microorganisms and exhausted to the outside, and in the deodorization process, water is sprayed onto the biofilter to supply moisture, and excess water from the spraying is collected and reused for the spraying.

The deodorizing process is a process in which the aerobically fermented material is decomposed and deodorized by the aerobic microorganisms contained in the biofilter by ventilating the indoor air in which the aerobically fermented material is being aerobically fermented through a biofilter made of a carrier such as wood chips to which aerobic microorganisms are attached, or soil containing aerobic microorganisms. In this deodorizing process, moisture is supplied to the biofilter by watering, and excess water from the watering is collected and reused for watering.

The waste treatment method of the invention of claim 9 has an exhaust adjustment process between the fermentation and drying process and the deodorization process, which reduces the humidity of the air exhausted from the room where the aerobically fermented material is being aerobically fermented, and in the deodorization process, the air whose humidity has been adjusted in the exhaust adjustment process is subjected to the biological deodorization and exhausted to the outside.

The exhaust adjustment process is a process for adjusting the humidity of the air discharged from the room where the aerobically fermented material is being aerobically fermented by mixing the air discharged from the room where the aerobically fermented material is being aerobically fermented with air having a lower relative humidity than the air discharged from the room, thereby reducing the humidity of the air discharged from the room where the aerobically fermented material is being aerobically fermented, and the mixed conditioned air is then supplied to the biological deodorization process.

The waste treatment method according to the present invention further comprises a biogas utilization step of refining the biogas and using it as fuel to supply heat and electricity.
The biogas utilization process is a process in which the biogas is refined and then used as fuel to generate electricity and heat. For example, the biogas is used as fuel in a gas engine generator and a steam boiler, a heat exchanger, or the like to generate electricity, and the waste heat generated at that time can be extracted as hot water or steam using a steam boiler, a heat exchanger, or the like, and the hot water or steam can be used to heat or keep warm during methane fermentation. Of course, the refined biogas can also be used as natural gas.

According to the waste treatment plant of the invention of claim 1, the plant comprises a pretreatment facility for separating waste into a high-water content methane fermentation target material to be subjected to methane fermentation and a low-water content selection residue, and preparing the methane fermentation target material into a slurry-like state; a methane fermentation facility for producing biogas by methane fermenting the slurry-like methane fermentation target material; and a mixing operation unit for mixing the slurry-like methane fermentation residue after the methane fermentation of the methane fermentation target material with the selection residue, and further adding a bulk density adjusting material for increasing the volume and a microbial attachment body having aerobic microorganisms attached thereto, to prepare an aerobic fermentation target material to be subjected to aerobic fermentation. The system is equipped with an aerobic fermentation and drying facility that aerobically ferments and dries the aerobically fermented material, and a post-treatment facility that selects solid fuel raw materials and/or compost raw materials from the aerobically fermented and dried material after the aerobically fermented and dried material, so that part of the waste is subjected to methane fermentation to produce biogas that can be converted into energy such as heat or electricity or used as natural gas, and the methane fermentation residue from the methane fermentation process is mixed with the remaining waste, bulk density adjusting material, and microbial adhesion material, and then aerobically fermented and dried to produce solid fuel raw materials and/or compost raw materials.

In particular, by mixing the slurry-like methane fermentation residue after methane fermentation with the remaining sorting residue of the waste and further adding a bulk density adjusting material and microbial adhesion bodies to increase the volume and create an aerobically fermented product, the aerobically fermented product has an appropriate amount of moisture and easily decomposable organic matter for the growth and activation of aerobic microorganisms, and the incorporation of the bulk density adjusting material ensures a certain amount of void space and good ventilation, so that the aerobic microorganisms attached to the microbial adhesion bodies predominate and work actively, and aerobic fermentation progresses. The fermentation heat can then be used to evaporate and remove the large amount of moisture contained in the slurry-like methane fermentation residue. Therefore, moisture can be dried and removed without the need for thermal energy for heating and drying, and no drainage equipment is required, so energy costs can be reduced and waste can be effectively recycled.

The waste treatment plant according to the invention of claim 2 further includes a first circulating water facility that collects wastewater from the aerobic fermentation and drying facility that aerobically ferments the aerobic fermentation material, filters it, and then sprays the aerobic fermentation material being aerobically fermented in the aerobic fermentation and drying facility. This allows the wastewater that seeps out from the aerobic fermentation material to be collected without being discharged as exhaust water, and after removing foreign matter with a filter, it is used to spray the aerobic fermentation material, thereby uniformly rehydrating the aerobic fermentation material being aerobically fermented in the aerobic fermentation and drying facility. Therefore, in addition to the effect of claim 1, the processing efficiency of aerobic fermentation and drying can be improved.

According to the waste treatment plant of the invention of claim 3, there is further provided a deodorization facility which biologically deodorizes the air discharged from the fermentation and drying equipment in which the aerobically fermented material is aerobically fermented, using a biofilter containing aerobic microorganisms, and exhausts the air to the outside. Therefore, in addition to the effects of claim 1 or 2, odorous air discharged from the aerobic fermentation and drying equipment in which the aerobically fermented material is aerobically fermented is deodorized in the biological deodorization device and then exhausted to the outside.
In addition, by providing a second circulating water facility that supplies moisture to the biofilter of the deodorizing equipment by sprinkling water and collects the surplus water to be used again for sprinkling, the moisture required for the activation of the aerobic microorganisms in the biofilter can be replenished and the moisture supply can be made uniform, and furthermore, by reusing the surplus water from sprinkling, the aerobic microorganisms in the biofilter can be moved and the distribution of the aerobic microorganisms can be made uniform, thereby obtaining a stable deodorizing efficiency of odor components. Furthermore, by repeatedly reusing the surplus water from sprinkling, it is possible to minimize the replenishment of moisture from outside, and low costs can be achieved.

According to the waste treatment plant of the invention of claim 4, the air discharged from the aerobic fermentation drying equipment in which the aerobic fermentation treatment material is aerobically fermented is mixed with air having a lower relative humidity than the air discharged from the aerobic fermentation drying equipment, and the mixed air is output to the deodorization equipment. In the air plenum chamber, the air discharged from the aerobic fermentation drying equipment is mixed with dry air having a lower relative humidity than the air discharged from the aerobic fermentation drying equipment to adjust the humidity to a low level, and then the air is biologically deodorized in the deodorization equipment and exhausted to the outside.

That is, the humid air discharged from the aerobic fermentation and drying equipment, which aerobically ferments and dries the aerobically fermented material, is mixed with low humidity air in the air plenum chamber, thereby lowering the relative humidity before being input to the deodorization equipment. Therefore, in addition to the effect described in claim 3, the water vapor exhausted from the aerobic fermentation and drying equipment is discharged as exhaust water within the deodorization equipment, making it difficult for it to accumulate in excess, and allowing a larger amount of moisture to be exhausted to the outside.

According to the waste treatment plant of the invention of claim 5, the plant further includes a cogeneration facility that refines the biogas and supplies heat and electricity by using the refined biogas as fuel. In addition to the effects of any one of claims 1 to 4, the biogas can be used more efficiently as an energy source. In particular, waste heat can be extracted as hot water or steam and used to heat or keep the methane fermentation equipment warm, reducing the costs of heating or keeping the methane fermentation equipment warm.

According to the waste treatment method of the invention of claim 6, in the pretreatment process, the waste is separated into a high-water content methane fermentation target material to be subjected to methane fermentation and a low-water content selection residue other than the methane fermentation target material, the methane fermentation target material is conditioned into a slurry, the slurry-like methane fermentation target material is methane fermented in the methane fermentation process to generate biogas, the slurry-like methane fermentation residue after the methane fermentation of the methane fermentation target material is mixed with the selection residue in the mixing process, and a bulk density adjusting material for increasing the volume and a microbial attachment body having aerobic microorganisms attached thereto are added to prepare an aerobic fermentation target material to be subjected to aerobic fermentation. In the aerobic fermentation and drying process, the aerobically fermented material is aerobically fermented and dried, and in the post-treatment process, solid fuel raw materials and/or compost raw materials are selected from the aerobically fermented and dried material after the aerobically fermented and dried material. A portion of the waste is subjected to methane fermentation to produce biogas that can be converted into energy such as heat or electricity or used as natural gas, and the methane fermentation residue from the methane fermentation process is mixed with the remaining waste, bulk density adjusting material, and microbial adhesion material, and these are aerobically fermented and dried to produce solid fuel raw materials and/or compost raw materials.

In particular, by mixing the slurry-like methane fermentation residue after methane fermentation with the remaining sorting residue of the waste and further adding a bulk density adjusting material and microbial adhesion bodies to increase the volume and create an aerobically fermented product, the aerobically fermented product has an appropriate amount of moisture and easily decomposable organic matter for the growth and activation of aerobic microorganisms, and the incorporation of the bulk density adjusting material ensures a certain amount of void space and good ventilation, so that the aerobic microorganisms attached to the microbial adhesion bodies predominate and work actively, and aerobic fermentation progresses. The fermentation heat can then be used to evaporate and remove the large amount of moisture contained in the slurry-like methane fermentation residue. Therefore, moisture can be dried and removed without the need for thermal energy for heating and drying, and no drainage equipment is required, so energy costs can be reduced and waste can be effectively recycled.

According to the waste treatment method of the invention of claim 7, in the aerobic fermentation and drying process, wastewater seeping out from the aerobically fermented material is collected, filtered, and then sprayed onto the aerobically fermented material. That is, the wastewater seeping out from the aerobically fermented material is collected without being discharged as exhaust water, and after removing foreign matter with a filter, it is used to spray onto the aerobically fermented material, thereby uniformly rehydrating the aerobically fermented material. Therefore, in addition to the effect of claim 6, the processing efficiency of aerobic fermentation and drying can be improved.

According to the waste treatment method of the invention of claim 8, there is further provided a deodorization step in which the air inside the room where the aerobically fermented material is being aerobically fermented is biologically deodorized by a biofilter containing aerobic microorganisms and then exhausted to the outside. Therefore, in addition to the effects of claim 6 or 7, odorous air exhausted from the room where the aerobically fermented material is being aerobically fermented is deodorized and then exhausted to the outside. Therefore, odors are not exhausted to the outside.
In the deodorizing process, water is sprayed onto the biofilter to supply moisture, and the excess water is collected and reused for spraying, replenishing the moisture required for the activation of the aerobic microorganisms in the biofilter and equalizing the moisture supply.Furthermore, the reuse of the excess water from spraying can move the aerobic microorganisms in the biofilter and equalize their distribution, thereby providing stable deodorizing efficiency of odorous components.In addition, because the excess water from spraying is repeatedly reused, it is possible to minimize the need to replenish moisture from outside, resulting in low costs.

According to the waste treatment plant of the invention of claim 9, between the aerobic fermentation drying process and the deodorization process, there is an exhaust adjustment process for mixing the air discharged from the room where the aerobically fermented material is aerobically fermenting with air having a lower relative humidity than the exhausted air, and in the deodorization process, the air mixed in the exhaust adjustment process is biologically deodorized and exhausted to the outside, so that the air discharged from the room where the aerobically fermented material is aerobically fermenting is mixed with dry air having a lower relative humidity than the air discharged from the room, and then the air is biologically deodorized and exhausted to the outside.

That is, the high humidity air discharged from the room where the aerobically fermented material is aerobically fermented and dried is mixed with low humidity air to relatively reduce the humidity before being used for deodorization. Therefore, in addition to the effect described in claim 8, the water vapor discharged from the room where the aerobically fermented material is aerobically fermented and dried is less likely to be discharged as exhaust water within the deodorization equipment of the deodorization process, and the amount of moisture discharged to the outside can be increased.

According to the waste treatment method of the invention of claim 10, the method further includes a biogas utilization process in which the biogas is refined and then used as fuel to supply heat and electricity. In addition to the effects of any one of claims 6 to 9, the biogas can be used more efficiently as an energy source. In particular, the waste heat can be extracted as hot water or steam and used to heat or insulate the methane fermentation equipment that performs methane fermentation, thereby reducing the costs of heating or insulating the equipment during methane fermentation.

FIG. 1 is a flow chart of a waste treatment process in a waste treatment plant according to an embodiment of the present invention. FIG. 2 is a conceptual diagram of a pretreatment process and a methane fermentation process in a waste treatment plant according to an embodiment of the present invention. FIG. 3 is a conceptual diagram of the mixing process, the aerobic fermentation drying process, the exhaust gas adjustment process, and the deodorization process of a waste treatment plant according to an embodiment of the present invention. FIG. 4 is a conceptual diagram of a post-treatment process in a waste treatment plant according to an embodiment of the present invention.

The following describes an embodiment of the present invention with reference to the drawings. Note that in the embodiments, the same symbols and reference characters shown in the drawings indicate the same or corresponding functional parts, and therefore, redundant explanations thereof will be omitted here.

First, an outline of the overall flow of waste treatment in a waste treatment plant according to an embodiment of the present invention will be described mainly with reference to the flow chart of FIG.
Waste 1A, such as household or business general waste, is discharged as burnable garbage such as food waste and paper scraps at homes or businesses and collected and transported by a waste collection truck 11. When the waste is received at a receiving yard Y1 in a building 110, the waste 1A is first crushed by a crusher 14 in a pre-processing process in step S11, where the dust bags containing the food waste, paper, plastics, etc. of the waste 1A are broken, and the waste is reduced in volume by rough crushing, crushing, etc.

In the subsequent sorting process of step S12, the broken waste 1A is sorted by particle size and weight (wind force) using a sorting machine 18, and the oversized fraction that is lighter than the specified particle size is sorted as sorting residue 10A, and the remaining undersized fraction that is less than the specified particle size is sorted as methane fermentation target material 10B to be subjected to methane fermentation. In this particle size and weight sorting, high moisture content materials such as food waste containing a large amount of organic matter suitable for decomposition by methane fermentation and small moist paper scraps are sorted into an undersized fraction and sorted as high moisture content methane fermentation target material 10B to be subjected to methane fermentation, and large size food waste, large size dry paper scraps, plastics including plastic bags, cloth, etc. are sorted into an oversized fraction and included in the low moisture content sorting residue 10A.

The sorted residue 10A sorted in the sorting process of step S12 is transported to a waste stockyard Y2 in building 110 to await the next processing, while the methane fermentation treatment target material 10B sorted in the sorting process of step S12 is dumped into a sorted waste pit P1 in building 110.
Here, the waste 1B such as food waste and animal and plant residues as industrial waste received at the receiving yard Y1 contains little polythene bags, plastics, etc., so it is possible to dump it into the sorted waste pit P1 without the above-mentioned crushing or sorting and collect it there. Hereinafter, the waste 1B such as animal and plant residues dumped into the sorted waste pit P1 will be collectively referred to as the material to be subjected to methane fermentation treatment 10B.
The high-water content methane fermentation treatment material 10B that was dumped into the sorted waste pit P1 is dumped into a mixing adjustment tank 19 in the moisture adjustment process of step S13, where the solids are broken down by stirring using a mixer (agitator) or the like, and the material is conditioned into a slurry-like methane fermentation treatment material 10B with a predetermined solids concentration.

The slurry-like methane fermentation target material 10B is fed into the methane fermentation tank 21 of the methane fermentation equipment in the next step S20, the methane fermentation process, where it is fermented by anaerobic microorganisms to produce biogas G containing methane gas.

The biogas G produced in the methane fermentation tank 21 is refined by a refining device 31 such as a desulfurization device in the refining process of step S31 as a biogas supply process, and is then temporarily stored in a gas holder 32, from which it is sent to a gas engine generator or the like of a cogeneration facility as a biogas utilization facility, and is used as fuel in the biogas utilization process of step S32 and converted into electricity and heat.

On the other hand, the methane fermentation residue 150 in the form of a slurry after the methane fermentation treatment target 10B is subjected to methane fermentation in the methane fermentation tank 21 is collected from the methane fermentation tank 21 and transported to a mixing yard Y3 serving as a mixing work section in the building 110. The sorting residue 10A transported from the waste stockyard Y2 in the building 110 described above is also collected in this mixing yard Y3, where the methane fermentation residue 150 and the sorting residue 10A, as well as a bulk density adjusting material 2 such as wood chips that increases the volume in order to form many voids for ventilation in the pile of the methane fermentation residue 150 and the sorting residue 10A, and a microbial-attached material 3 such as fine aerobic fermentation residue particles to which many aerobic microorganisms are attached are mixed to produce the aerobic fermentation treatment target 100 to be subjected to aerobic fermentation.
That is, in the mixing process of step S40, the slurry-like methane fermentation residue 150 remaining after anaerobic fermentation of the methane fermentation treatment material 10B, the sorting residue 10A, the bulk density adjustment material 2, and the microbial attachment material 3 are mixed to produce the aerobic fermentation treatment material 100 to be subjected to aerobic fermentation.

Next, the aerobically fermented material 100 is loaded into the concrete housing 121 of the aerobic fermentation drying apparatus 120 in the aerobic fermentation and drying facility, which is stored in whole or in part within the building 110, where it is aerobically fermented and dried for a specified number of days as the aerobic fermentation and drying process of step S50.
At this time, in the aerobic fermentation drying apparatus 120, water is sprinkled (sprayed) on the aerobically fermented material 100 in the housing 121. In particular, in this embodiment, wastewater discharged into the building 110 and the housing 121, i.e., wastewater seeping out from the waste materials 1A and 1B, the sorting residue 10A, the material to be methane fermented 10B, and the methane fermentation residue 150, is collected and filtered by a filter 172, and the filtered water is used for sprinkling (spraying) into the housing 121. Furthermore, in the housing 121 of the aerobic fermentation drying apparatus 120, oxygen is replenished by replacing the exhaust of air (odor) with the intake of fresh air (introduced air) from the building 110, and the inside of the housing 121 is controlled to a predetermined temperature and negative pressure.

In this embodiment, the humid air (odor) discharged from the housing 121 is introduced into the air plenum chamber 130 as an exhaust adjustment process in step S60, where it is mixed with the introduced air taken in from inside the building 110 outside the housing 121, and then sent to the biological deodorization device 140 of the deodorization equipment installed outside the building 110.
Then, in the biological deodorization process of step S70, the mixed air from the air plenum chamber 130 passes through a biofilter 142 in the biological deodorization device 140, which is made of a carrier such as wood chips to which aerobic microorganisms are attached, and the odorous components contained therein are decomposed and deodorized by the aerobic microorganisms in the biofilter 172, and the odorous components are exhausted (released) to the outside, i.e., into the outdoor atmosphere.
At this time, in the biological deodorization device 140, water is sprayed onto the bio-filter 172, and the surplus water is collected and reused as water spray.

Meanwhile, the aerobic fermentation and drying treatment product 200 that has completed aerobic fermentation and drying in the aerobic fermentation and drying device 120 is sorted in step S81 as a post-processing step to remove non-combustibles 230 by magnetic sorting or the like and vinyl chloride 240 by infrared sorting or the like, and is also separated into solid fuel raw material 210 and/or compost raw material 220, bulk density adjusting material 2 such as wood chips mixed in the mixing step of step S40 described above, and fine aerobic fermentation residue to be used as microbial adhesion material 3 to which aerobic microorganisms are attached, for example, based on criteria such as size and gravity (specific gravity).

In this way, the waste treatment plant of this embodiment separates waste 1A, such as general household and office waste containing a mixture of food waste, plastic, paper, cloth, etc., based on criteria such as particle size, into waste to be fermented by methane fermentation, i.e., high-water content methane fermentation target material 10B containing a large amount of easily decomposable organic matter such as food waste, and the rest of the waste, selected residue 10A, and generates biogas G by methane fermenting the selected methane fermentation target material 10B, which may also include waste 1B such as industrial waste food waste and animal and plant residues.
Furthermore, the methane fermentation residue 150 remaining after the methane fermentation treatment material 10B has been subjected to methane fermentation is combined with the selection residue 10A remaining after the methane fermentation treatment material 10B has been selected from the waste 1A, and is further mixed with the bulk density adjusting material 2 and the microbial adhesion body 3 to form the aerobically fermented material 100, which is aerobically fermented and dried to produce a solid fuel material 210, a compost material 220, etc. In other words, biogas G is produced from the wastes 1A and 1B, which contain a mixture of plastic, paper, cloth, etc., and the wastes are recycled into solid fuel material 21, compost material 22, etc.

In particular, in the waste treatment plant of this embodiment, the methane fermentation residue 150 after methane fermentation of the methane fermentation target material 10B is combined with the remaining selection residue 10A obtained by selecting the methane fermentation target material 10B from the waste 1A, and then mixed with the bulk density adjusting material 2 and the microbial attachment material 3 to create the aerobically fermented target material 100. In the aerobically fermented target material 100, ventilation is ensured through appropriate gaps within the pile, suppressing the occurrence of excess moisture or oxygen-deficient parts, suppressing anaerobic fermentation, and allowing aerobic fermentation and drying to proceed, releasing moisture into the outside air as water vapor. Therefore, the moisture in the wastewater can be treated at low energy costs without the need for special equipment for solid-liquid separation, wastewater treatment, heating treatment, etc.

Next, the overall configuration of the waste treatment plant of this embodiment and the overall flow of waste treatment will be described in detail mainly with reference to FIGS.
Among the wastes 1A and 1B that are lowered to the receiving yard Y1 in the building 110 of the waste treatment plant of this embodiment and received in the building 110, the waste 1A, such as household or business general waste, collected as burnable waste (combustible waste) by the dust collection truck 11 is relayed by a wheel loader 12 or the like and fed into the hopper of the crusher 14 via a belt conveyor 13 or the like. The crusher 14 breaks bags by applying an external force, and also crushes and fragments large solid objects, or reduces the volume by crushing them. That is, the crusher 14, which rotates at a low speed, has a bag breaking function, a crushing function, and a crushing function for performing multi-stage volume reduction, homogenization, and bag breaking on the received waste 1A, and breaks and roughly crushes the dust bags containing plastic, paper, cloth, etc. Therefore, the waste 1A that is the result of processing by this crusher 14 is the received waste 1A that has been broken into bags and reduced in volume. In carrying out the present invention, the crusher 14 is only required to have at least a bag breaking function, and the crushing method may be any of impact, shear force, rotational force, compression force, and the like.

Next, the waste 1A that has been broken into bags and roughly crushed in the crusher 14 is sorted by size (particle size) and weight (wind force) in the sorting machine 18 into materials to be subjected to methane fermentation treatment 10B that are smaller than a specified particle size, i.e., the undersized fraction, and materials that are larger than the specified particle size or are lightweight, i.e., the oversized fraction, sorting residue 10A.
The undersized fraction of methane fermentation treated material 10B contains a large amount of small-sized food waste, wet paper, etc., from the waste 1A, has a higher moisture content than the sorting residue 10A, and contains a large amount of easily decomposable organic matter. On the other hand, the oversized fraction of sorting residue 10A contains a large amount of dry paper, plants, cloth, plastic (resin) including plastic bags, etc., in addition to the large-sized food waste from the waste 1A.
In carrying out the present invention, crushing, fractionation, and conditioning may each be performed as separate steps, or crushing and fractionation may be performed simultaneously, fractionation and conditioning may be performed simultaneously, or crushing, fractionation, and conditioning may be performed simultaneously.

Then, the sorted residue 10A separated from the waste 1A is transported and collected in the waste stockyard Y2 in the building 110 to await the next processing.
On the other hand, material to be subjected to methane fermentation treatment 10B that has been separated from waste 1A is dumped into a separated waste pit P1 in a building 110.

When the present invention is implemented, the waste 1B, such as industrial food waste, animal and plant residues, paper scraps, wood chips, and fiber scraps, may be directly thrown into the sorted waste pit P1 among the wastes 1A and 1B transported by the dust collection vehicle 11 or the arm roll vehicle and dropped into the receiving yard Y1 in the building 110. If the waste 1B is industrial food waste, animal and plant residues, paper scraps, wood chips, fiber scraps, etc., which are collected and separated, it may be thrown into the sorted waste pit P1 without being crushed or sorted, or it may be thrown into the sorted waste pit P1 without being sorted after the dust bag is broken or crushed by the crusher 14. Of course, even if the waste 1B is industrial food waste, animal and plant residues, paper scraps, wood chips, fiber scraps, etc., it may be thrown into the sorted waste pit P1 after being crushed and sorted in the same way as the waste 1A of household or business general waste.
Hereinafter, waste 1B such as animal and plant residues placed in the sorting waste pit P1 will be collectively referred to as material to be subjected to methane fermentation treatment 10B.

The high-water content methane fermentation target material 10B collected in the sorting waste pit P1 is then transferred to the mixing and adjustment tank 19 using a pump or the like and poured into the mixing and adjustment tank 19, where the solids are broken down by stirring using a mixer (agitator) or the like, and adjusted to a slurry-like methane fermentation target material 10B with a predetermined solids concentration according to the fermentation method, whether wet or dry. If the methane fermentation method is a dry method, the solids concentration is adjusted to 15 to 40% by mass, and if it is a wet method, the solids concentration is adjusted to around 10% by mass.

Normally, methane fermentation treatment material 10B, which contains a large amount of food waste, can be made into a slurry with a solids concentration of about 10 to 30% by mass without adding water from the outside, but water can be added from the outside if necessary. In this case, water in water storage tanks 173A, 173B or water storage tank 183, which will be described later, can be used. Alternatively, liquid waste such as livestock manure, organic sludge, waste beverages, and animal and vegetable oils can be received and the water therefrom can be used to adjust the solids concentration to a predetermined level.

The slurry-like methane fermentation target material 10B homogenized in the mixing adjustment tank 19 is then quantitatively supplied to a methane fermentation tank 21 using a pump or the like.
The slurry-like methane fermentation target material 10B homogenized in the mixing adjustment tank 19 may be supplied directly to the methane fermentation tank 21 in a quantitative manner, or may be stored in a slurry supply adjustment tank (not shown) and then supplied to the methane fermentation tank 21 in a quantitative manner.
That is, the waste treatment plant of this embodiment has pretreatment facilities including a crusher 14, a sorted waste pit P1, a mixing adjustment tank 19, etc., and also has a methane fermentation tank 21 as a methane fermentation facility.

In the methane fermentation tank 21 containing the slurry-like material to be subjected to methane fermentation treatment 10B, the interior is set to predetermined anaerobic conditions and temperature, and methane fermentation of the material to be subjected to methane fermentation treatment 10B is carried out by anaerobic microorganisms (methane-producing bacteria).
The methane fermentation tank 21 has an airtight structure formed, for example, with a housing made of reinforced concrete or steel plate, but the structure inside the tank is not particularly important here and is designed according to the wet or dry fermentation method, fermentation temperature, etc.
The methane fermentation treatment method of the methane fermentation treated product 10B in the methane fermenter 21 may be a dry method or a wet method, and in the case of a wet method, for example, a one-tank type in which acid production and methane production are combined, a two-tank type provided with a solubilization tank, or a fermenter such as a multi-layer type or a fixed bed is used, and medium temperature fermentation is performed at about 35° C. or high temperature fermentation is performed at about 55° C. On the other hand, in the case of a dry method, for example, a fermenter such as a continuous type of the Dranko method or a combo gas method, or a batch type of the Bioferm method is used, and high temperature fermentation is performed at about 55° C. Among them, the Dranko method is preferable for odor countermeasures because it is a continuous treatment in a closed system.

Preferably, for example, a dry method is used in which the solid content concentration of the slurry-like methane fermentation target material 10B to be fed into the methane fermentation tank 21 is set to about 15 to 30 mass %, and methane fermentation is performed under high temperature conditions of about 55° C. In such a dry method under high temperature conditions, the amount of water added from the outside to the mixing adjustment tank 19 is minimized, the water content of the methane fermentation residue 150 is reduced, that is, the water content of the methane fermentation residue 150 is reduced, the load of the subsequent drying process in the aerobic fermentation drying device 120 is reduced, and the amount of wastewater discharged from the methane fermentation residue 150 can be reduced. In addition, in the dry methane fermentation method, the slurry-like methane fermentation target material 10B with a high solid content concentration is treated under a high load without a complicated solubilization process, so that the processing efficiency of the solid content can be increased, and the high solid content concentration maintains the bacterial cell concentration high, and the rate of biogasification of organic matter per unit volume of the fermentation tank can be increased. Even taking into consideration the mechanical operating conditions such as the subsequent transportation of the methane fermentation residue 150 by the screw conveyor 41, the solid content concentration of the slurry-like methane fermentation target material 10B to be fed into the methane fermenter 21 is preferably about 15 to 30 mass %.
In particular, in this embodiment, the methane fermentation target material 10B, which is a mixture of food waste, paper waste, etc., is subjected to methane fermentation. Therefore, a high organic matter load is applied, and it is possible to suppress the accumulation of ammonia nitrogen, which inhibits methane fermentation, and increase the efficiency of biogas G generation.

In the methane fermentation of the slurry-like methane fermentation target material 10B in the methane fermentation tank 21, first, in the solubilization/hydrolysis process, facultative anaerobic bacteria or obligate anaerobic bacteria hydrolyze the biodegradable high molecular organic matter in the methane fermentation target material 10B, such as hydrocarbons, proteins, lipids (fats), and fibers, into monosaccharides, peptides, amino acids, glycerin, fatty acids, etc., and reduce them to low molecular weight substances. Next, in the acid fermentation process, the hydrolyzed low molecular weight organic matter is decomposed by acid fermentation bacteria into alcohol, volatile fatty acids (VFAs) such as butyric acid and propionic acid, carbon dioxide, hydrogen sulfide, and ammonia. Next, in the hydrogen and acetic acid production process, acetic acid bacteria decompose fatty acids with three or more carbon atoms, such as butyric acid and propionic acid, into acetic acid, or carbon dioxide and hydrogen or formic acid. Finally, in the methane production process, methanogens generate biogas G (methane and carbon dioxide) and water from acetic acid or hydrogen.

In the waste treatment plant of this embodiment, the biogas G of methane and carbon dioxide generated in the methane fermentation tank 21 is purified by removing impurities in a purification device 31 that purifies the biogas G, such as a desulfurization device that removes hydrogen sulfide and sulfur oxides from the biogas G, a separation device equipped with a carbon dioxide selective permeable membrane that separates carbon dioxide, and a moisture removal device, and is then temporarily stored in a gas holder 32. The desulfurization method in the desulfurization device is not particularly limited, and for example, dry desulfurization, wet desulfurization, biological desulfurization, etc. can be used. In addition, the moisture removal device can use, for example, an inertial collision method or an adsorption method. Furthermore, the storage method for storing the biogas G in the gas holder 32 is also not particularly limited, and for example, a wet method, a two-membrane method, a steel-coated membrane type, an adsorption storage type, etc. can be used.

Furthermore, the waste treatment plant of this embodiment is provided with a gas flare (surplus gas combustion device) (not shown), and when excess biogas G is generated, the excess biogas G is safely burned and released by the gas flare (not shown).

In the waste treatment plant of this embodiment, the biogas is sent from the gas holder 32 to a gas cogeneration facility 33 as a gas utilization facility, where it is converted into electricity and heat. For example, the gas cogeneration facility 33 is equipped with a generator such as a gas engine generator, and the refined biogas G is combusted in the generator to run an engine, which in turn runs the generator to generate electricity, which can be used to obtain power to supply electricity, and the waste heat generated simultaneously with the power generation can be extracted as hot water or steam using a heat exchanger, steam boiler, etc.

That is, in the waste treatment plant of this embodiment, a supply means is provided for supplying hot water and steam from the waste heat generated in the gas cogeneration facility 33 to the methane fermentation tank 21 of the methane fermentation facility, and the hot water and steam from the waste heat generated by the power generation in the gas cogeneration facility 33 are used as a heat source for heating and keeping warm the methane fermentation tank 21. That is, the gas cogeneration facility 33 as a gas utilization facility is composed of a gas engine generator, a heat exchanger, a steam boiler, etc.
The electric power generated by the gas cogeneration facility 33 can be supplied to the outside or used within the plant. Of course, the hot water and steam generated by the surplus waste heat generated by the gas cogeneration facility 33 can also be supplied to the outside.

In particular, in the waste plant of this embodiment, as described below, the methane fermentation residue 150 is combined with the sorted residue 10A and further mixed with the bulk density adjusting material 2 and the microbial adhesion material 3 to create the aerobically fermented material 100, which is then aerobically fermented and the moisture is dried using the fermentation heat and airflow, thereby reducing energy costs and treating the moisture. Since there is no need to use the energy of the biogas G for heating, drying, or purification to treat the moisture, the biogas G can be used more efficiently.

When implementing the present invention, a boiler may be installed as a gas utilization facility and the refined biogas G may be used as fuel for the boiler, or the refined biogas G may be supplied from the gas holder 32 to a city gas facility and used as a city gas raw material. In addition, the refined biogas G may be used as fuel for fuel cells or as fuel for gas-powered automobiles. In other words, the refined biogas G may be used as natural gas.

On the other hand, the slurry-like methane fermentation residue (digestion liquid) 110 obtained after methane fermentation of the material to be methane fermented 10B in the methane fermentation tank 21 is discharged and recovered from the methane fermentation tank 21, and is transferred to a metered supply device 42 installed in a mixing yard Y3 serving as a mixing work section within the building 110 via a screw conveyor 41 without solid-liquid separation. During this time, a storage tank may be provided to temporarily store the methane fermentation residue 150. In addition, since the methane fermentation residue 150 contains anaerobic microorganisms, it is also possible to recover a portion of the methane fermentation residue 150, return it to the mixing adjustment tank 19, and use it as a seed bacteria for methane fermentation of the material to be methane fermented 10B.

The sorted residue 10A is transferred from the waste stockyard Y2 in the building 110 where it was collected and is dropped off at the mixing yard Y3. Also, methane fermentation residue 150 is supplied from a measuring device 42, and the sorted residue 10A and methane fermentation residue 150 are mixed and consolidated. In addition, bulk density adjusting material 2 such as wood chips to increase the bulk and microbial-attached material 3 such as fine fermentation residue with aerobic microorganisms attached are also added to the mixture, which is then mixed uniformly by a wheel loader or the like to form the aerobically fermented material 100 to be subjected to aerobic fermentation.

Here, the bulk density adjusting material 2 to be mixed with the sorting residue 10A and the methane fermentation residue 150 may be an organic material of a predetermined size that can increase the volume of the aerobically fermented material 100 to be aerobically fermented and form ventilation gaps within the material, and preferably, an organic material that is water-absorbent and hygroscopic and can support microorganisms, such as wood materials such as wood chips, or solid fuels such as RDF (Refuse Derived Fuel) and RPF (Refuse Paper & Plastic Fuel) made by converting the solid fuel raw material 210 sorted from the aerobically fermented and dried material 200 into a solid fuel, can be used.
Wood chips and solid fuel are low cost and can easily support aerobic microorganisms, allowing for repeated reuse and promoting efficient aerobic fermentation. This allows for promotion of aerobic fermentation at low cost. In particular, RDF, which uses solid fuel, contains a large amount of decomposed food waste, so heat (fermentation heat) can be expected to be generated by aerobic fermentation by aerobic microorganisms, and the effect of promoting the progress of aerobic fermentation and drying of the aerobic fermentation treatment material 100 can be expected.

The bulk density adjusting material 2, such as wood chips or solid fuel, for forming a predetermined gap in the pile of the aerobic fermentation treatment material 100 is preferably, for example, in a diameter of 20 mm or more and less than 50 mm, more preferably, 20 mm or more and 48 mm or less, and even more preferably, 22 mm or more and 48 mm or less, and in a length of 20 mm or more and 250 mm or less, more preferably, 50 mm or more and 230 mm or less, and even more preferably, 80 mm or more and 200 mm or less. If the dimensions are too large, the amount of sorting residue 10A and methane fermentation residue 150 processed will be reduced, resulting in uneconomical operation, while if the dimensions are too small, the predetermined gap cannot be secured at the bottom of the pile, which tends to cause insufficient ventilation, slowing down the processing speed and reducing the efficiency of fermentation and drying. If the dimensions are within this range, the predetermined gap can be secured even at the bottom of the pile, preventing oxygen deficiency, allowing efficient fermentation and drying processing, and economical operation. Thus, efficient processing is possible.

In addition, the efficiency of the aerobic fermentation process is improved by mixing in the microbial adhesion body 3 with aerobic microorganisms attached. Since the aerobic fermentation dried product 200 that has been aerobically fermented has many aerobic microorganisms attached, the microbial adhesion body 3 can be the bulk density adjustment material 2 such as fine aerobic fermentation residue particles or wood chips that remain when the solid fuel material 210 or compost material 220 is selected from the aerobic fermentation dried product 200. Therefore, the bulk density adjustment material 2 such as wood chips after aerobic fermentation also functions as the microbial adhesion body 3. Of course, a separate carrier with aerobic microorganisms attached may also be used.

The aerobically fermented material 100, which is a mixture of the methane fermentation residue 150, the sorting residue 10A, the bulk density adjusting material 2, and the microbial adhering material 3 produced in the mixing yard Y3 in the building 110, is then transported by a wheel loader or the like into the housing 121 of the fermentation and drying device 120, which has an entrance/exit within the building 110 and is installed in continuity with the building 110, where it is subjected to aerobically fermentation and drying treatment.

Here, the housing 121 of the aerobic fermentation drying apparatus 120 may be made, for example, of concrete, and may be configured to maintain a sealed state sufficient to effectively block the air flows between the indoor and outdoor areas, and to freely control the indoor temperature so that it does not match the outdoor temperature.
The housing 121 usually has a loading/unloading opening that can be opened and closed with a door that can block the air flow between the inside and outside of the room. Even if there is a gap between the loading/unloading opening and the door, the air flow from the inside to the outside of the room is prevented by the negative pressure on the inside of the room, and the air flow from the outside to the inside of the room is permitted. The door is opened only when the aerobically fermented material 100 is loaded and the aerobically fermented and dried material 200 is unloaded, and is always closed during the treatment process.
The number of housings 121 of the fermentation and drying apparatus 120 is preferably multiple, but may be one. In the case of multiple housings, they are operated by batch processing, and the capacity and number of housings can be determined based on the number of operating days and the processing amount. The overall shape of the housing 121 is not particularly limited, and may be a cylinder with a square cross section that forms the bottom, both sides, and the ceiling, or a dome-shaped cylinder.

In the fermentation and drying apparatus 120 of this embodiment, indoor air is drawn in from the top of the housing 121 by a fan (blower) 165, and the air is compressed and ejected from the underside of the housing 121 to form an air circulation section 163 that circulates the air within the housing 121, and air is supplied by blowing air to the aerobic fermentation treatment material 100 loaded into the housing 121.
In addition, an air exhaust section 162 is provided to exhaust the indoor air of the housing 121, and an air intake section 161 is provided to introduce air from within the building 110 outside the housing 121 into the interior of the housing 121, providing ventilation to constantly maintain the interior of the housing 121 at negative pressure.

In the fermentation and drying apparatus 120 of this embodiment, the input into the housing 121 room of the air introduction section 161, which takes in air from the building 110 outside the housing 121 room, and the input into the housing 121 room of the air circulation section 163, which circulates air sucked in from the top of the housing 121 by spraying it out from the bottom, are combined, and a fan (blower) 165 is disposed in the path where the air introduction section 161 and the air circulation section 163 join together, and the air output from the top of the housing 121 by the suction of the fan 165 and the air taken in from the building 110 outside the housing 121 are combined and sprayed out from the bottom of the housing 121.

In particular, in the fermentation and drying apparatus 120 of this embodiment, a damper (flow rate control valve) 166a is provided on the input side (intake side) of the fan 165, in the path before the air introduction section 161 and the air circulation section 163 join, to adjust the amount of air introduced from inside the building 110 outside the housing 121 in the air introduction section 161. Also, in the path before the air introduction section 161 joins, a damper 166b is provided in the air circulation section 163 to adjust the amount of air taken in from the top of the housing 121. This makes it possible to adjust the temperature, oxygen amount, and pressure to maintain a negative pressure inside the housing 121 by individually adjusting the input amounts of both using the dampers 166a and 166b, without switching between the input of fresh air through the air introduction section 161 and the input of circulated air through the air circulation section 163.

Therefore, in the fermentation drying apparatus 120 of this embodiment, by driving the fan 165 arranged in the joining path of the air introduction section 161 and the air circulation section 163, indoor air is drawn in from the top of the housing 121 in the air circulation section 163, and air is also drawn in from inside the building 110 outside the housing 121 in the air introduction section 161, and the air output from the housing 125 and the introduced air taken in from inside the building 110 outside the housing 121 are mixed in the joining path of the air introduction section 161 and the air circulation section 163, and this is blown out from the fan 165 and ejected from the underside of the housing 121 as compressed air.
In other words, the compressed air that is sprayed from the underside of the housing 121 and input into the housing 121 is a mixture of air sucked in from the top of the housing 121 in the air circulation section 163 and air taken in from inside the building 110 outside the housing 121 in the air introduction section 161.
In this way, fresh air (introduced air) taken in from within the building 110 outside the housing 12 at the air inlet portion 161 is supplied to the housing 121 from the underside of the housing 121 , thereby replenishing oxygen within the housing 121 .

In this embodiment, the mixed air, which is the air sucked in from the top of the housing 121 in the air circulation section 163 and the air introduced in the air introduction section 161 from inside the building 110 outside the housing 121, is blown and supplied to the aerobic fermentation treatment material 100 from the bottom inside the housing 121. Since the mixed air has a relatively lower humidity than the air sucked in from the top of the housing 121, it is easier to evaporate the moisture in the aerobic fermentation treatment material 100 as it passes from top to bottom inside the aerobic fermentation treatment material 100.

In other words, the air sucked in from the top of the housing 121 in the air circulation section 163 contains a lot of moisture from the aerobically fermented material 100 and the moisture evaporated from watering, while the air taken in from inside the building 110 outside the housing 121 usually has relatively low humidity, so the air that is mixed with the two and sprayed out from the bottom of the housing 121 and aerated into the aerobically fermented material 100 has a relatively lower humidity than the air output from the top of the housing 121. Therefore, it is possible to increase the drying efficiency of drying the moisture in the aerobically fermented material 100 by the air that is aerated into the aerobically fermented material 100.

Furthermore, the building 110 is usually designed with poor ventilation to prevent odors, so it is less susceptible to the effects of outside air temperatures even in winter. However, the air inlet section 161 takes in air from inside the building 110 instead of outside air, so that the temperature drop in the air introduced from the air inlet section 161 is suppressed even in winter, the load on the aerobic microorganisms is reduced, and the decrease in the processing efficiency of aerobic fermentation and drying can be suppressed. In other words, by suppressing the change in temperature of the air introduced from the air inlet section 161 without being significantly affected by changes in outside air temperature, the load on the aerobic microorganisms is reduced, and the processing efficiency of aerobic fermentation and drying can be maintained.

In addition, in this embodiment, when the fan 165 is operating, the airflow of the air circulation section 163 and the air introduction section 161 does not stop, and oxygen is constantly supplied to the aerobic fermentation treatment material 100 by the air introduction section 161, thereby increasing the processing efficiency of the aerobic fermentation and drying of the aerobic fermentation treatment material 100 by aerobic microorganisms. In addition, by constantly operating the fan 165, including when the aerobic fermentation treatment material 100 is carried in and when the aerobic fermentation drying treatment material 200 is carried out, clogging of the suction and exhaust ports in the housing 121 can be prevented. If necessary, the air volume may be adjusted by controlling the speed of the fan 165 by inverter control, and it is also possible to perform energy-saving operation by reducing the rotation speed. When multiple housings 121 for batch processing are provided, it is preferable to provide a fan 165 for each housing 121.
Furthermore, in the fermentation drying apparatus 120 of this embodiment, the input into the housing 121 of the air circulation section 163, which circulates the air within the housing 121, and the input into the housing 121 of the air introduction section 161, which introduces air from within the building 110, are combined together, so that the number of parts can be reduced and the apparatus can be constructed at low cost.

In the fermentation drying apparatus 120 of this embodiment, an air discharge section 162 is formed to discharge the indoor air of the housing 121 to the outside, and a damper 163c is disposed therein to adjust the amount of air discharged from inside the housing 121. Therefore, by controlling the amount of air ( ^m3 /min) discharged to the outside of the air discharge section 162 and the amount of air ( ^m3 /min) introduced from inside the building 110 to the air introduction section 161 by the dampers 166a, 166b, 166c, it is possible to maintain a negative pressure inside the housing 121 to prevent odors inside the housing 121 from leaking outside, and also to adjust the temperature, amount of oxygen, etc. inside the housing 121.

That is, in the fermentation drying apparatus 120 of this embodiment, the amount of air introduced into the housing 121 from inside the building 110 outside the housing 121, the amount of circulating air drawn in from the top of the housing 121 and returned to the bottom of the housing 121, and the amount of air exhausted from the housing 121 to the outside can each be individually adjusted by dampers 166a, 166b, and 166c, so that the inside of the housing 121 does not become positive pressure; in other words, the inside of the housing 121 is at negative pressure to prevent air from flowing from the inside to the outside, preventing odors from inside the housing 121 from escaping outside the housing 121, and the temperature and oxygen environment inside the housing 121 is controlled to be suitable for the growth of aerobic microorganisms and the ventilation volume is controlled to promote drying.
As described below, the air exhaust section 162 that exhausts the air inside the housing 121 is connected to the air plenum chamber 130, where the air is mixed with the air introduced from inside the building 110 outside the housing 121, and then deodorized by the biological deodorizing device 140 and exhausted into the outside air (atmosphere).

In addition, in the fermentation and drying apparatus 120 of this embodiment, water is sprayed into the housing 121 from the top of the housing 121. This allows the moisture necessary for the activity and growth of the aerobic microorganisms that aerobically ferment the aerobic fermentation treatment material 100 to be uniformly added, thereby improving the processing efficiency of the aerobic fermentation.

In particular, in this embodiment, wastewater discharged within the housing 121, i.e., leachate seeping out from the aerobically fermented material 100 loaded into the housing 121 and excess water from sprinkling, and further, wastewater discharged (generated) in places other than the housing 121, such as waste materials 1A, 1B, the material to be subjected to methane fermentation treatment 10B, the methane fermentation residue 150, the sorting residue 10A, leachate seeping out from the material to be subjected to aerobically fermentation treatment 100 and equipment cleaning water, are collected and used to spray water inside the housing 121 after filtering out foreign matter with the filter 172.

That is, in this embodiment, a first circulating water system 171 is formed that collects wastewater discharged from the housing 121, and furthermore, wastewater discharged from within the building 110 other than the housing 121, and sprays it onto the aerobic fermentation treatment material 100 loaded inside the housing 121.

Housing 121 has a drainage groove formed at its bottom, through which the water contained in the aerobic fermentation treatment material 100 and the sprayed excess water are discharged outside the housing 121 and collected. After foreign matter and the like contained in the wastewater is removed by filter 172, the filtered water is returned to the housing 121 chamber and sprayed from the top of the chamber as watering to humidify the inside of housing 121.
In addition, a water collection structure for collecting wastewater is also provided within building 110 outside housing 121, and, similar to the wastewater collected from housing 121, foreign matter and the like is removed from the collected wastewater using filter 172, and the filtered water is then sprayed from the upper part of the interior of housing 121 as watering to humidify the interior of housing 121.
In other words, in the first circulating water system 171 of this embodiment, wastewater discharged from the housing 121 and wastewater discharged from a location separate from the housing 121 are collected, filtered by a filter 172, and then sprayed as water droplets inside the housing 121 using a watering nozzle provided on the ceiling side of the housing 121.

This first circulating water system 171 is provided with a water storage tank 173A for collecting wastewater discharged from the housing 121 and wastewater discharged from places other than the housing 121, a filter 172 for filtering water pressurized by a pump or the like and discharged from the water storage tank 173A, and a water storage tank 173B for storing purified water that has passed through the filter 172. The water collected in the water storage tank 173B is pressurized by a pump or the like and pumped to a spray nozzle provided inside the housing 121, and sprayed from the spray nozzle. The filter 172 may be any filter that removes dirt, sand, fine particles, etc. contained in the wastewater, but may pass aerobic microorganisms.
In this embodiment, a supply line 174 is provided so that water from a second circulating water system 181, which recovers and reuses water sprayed on a biological deodorizing device 140 (described later), can also be introduced into the water storage tank 173A of the first circulating water system 171 via a valve or the like. Furthermore, water from the outside, such as industrial water or drinking water, can also be introduced into the water storage tank 173B via a valve or the like.

Therefore, water discharged from the housing 121 and water generated in places other than the housing 121, such as inside the building 110, are collected in the water storage tank 173A. The water collected in the water storage tank 173A is then pumped by a pump or the like to the filter 172, where foreign objects are removed, and the water is then input into the water storage tank 173B. The water collected in the water storage tank 173B is then pressurized by a pump or the like and pumped to a spray nozzle installed inside the housing 121, where it is sprayed from the spray nozzle.

In this way, in the waste treatment plant of this embodiment, the wastewater discharged into the housing 121, including the moisture contained in the aerobic fermentation treatment material 100 and the excess water sprayed into the housing 121, is discharged outside the housing 121 through a drain formed at the bottom of the housing 121 and used as water spraying via the water storage tank 173A, filter 172, and water storage tank 173B, and is not discharged to the outside. Furthermore, wastewater generated in places other than the housing 121 is also collected and used to spray the aerobic fermentation treatment material 100, and is not discharged to the outside.

In addition, in the first circulating water system 171 of this embodiment, by providing water storage tanks 173A and 173B, it is possible to respond to fluctuations in the amount of moisture, and when there is a shortage of water in the water storage tanks 173A and 173B, water can be replenished from the second circulating water system 181 or from outside, thereby preventing excess moisture from being stored and reducing costs.

In this way, the first circulating water equipment 171 collects wastewater from within the housing 121, and also collects wastewater generated within the buildings 110 other than the housing 121, and sprays it into the housing 121. This makes it possible to equalize the supply of water and replenish moisture to the aerobically fermented material 100 undergoing aerobically fermentation within the housing 121 of the aerobic fermentation drying device 120. This prevents uneven distribution of aerobic fermentation and drying, enables uniform aerobic fermentation throughout the aerobically fermented material 100, and enables efficient aerobic fermentation and drying.

In particular, in the aerobic fermentation drying device 120, wastewater that seeps out from the aerobically fermented material 100 inside the housing 121 is sprayed onto the aerobically fermented material 100 after removing foreign matter with a filter 172 without being discharged to the outside, and the wastewater, including the surplus water from the spraying, is collected and used for repeated spraying. Since the wastewater generated inside the housing 121 contains aerobic microorganisms, the water that is sprayed as droplets also contains aerobic microorganisms, which allows the aerobic microorganisms to be uniformly distributed over the aerobically fermented material 100, improving the efficiency of the treatment by aerobic fermentation. In other words, the spraying of droplets also moves the aerobic microorganisms from top to bottom, enabling efficient aerobic fermentation treatment.

Furthermore, wastewater from within the housing 121 and wastewater generated within buildings 110 other than the housing 121 is collected and used for watering, so the moisture required by aerobic microorganisms for efficient aerobic fermentation treatment can be provided at low cost, and since wastewater is not discharged to the outside, purification for drainage is unnecessary.

The water that falls into the drain of the housing 121 may be sucked up by a pump or the like when a predetermined amount is collected and collected in the water storage tank 173A, or may flow to the water storage tank 173A side when a predetermined amount of water is collected. The drain component of the housing 121 may also be used as a component that inputs air into the housing 121 room. That is, the first circulating water equipment 171 may have a drain pipe that flows the water discharged from the drain provided at the bottom of the housing 121 to the water storage tank side, and the air to be introduced into the housing 121 of the air introduction section 161 and the air circulation section 163 may be introduced from the drain side through the above pipe. In this case, when the drained water is flowed to the water storage tank 173A side by a suction pump or the like, it is only necessary to switch the software to stop the introduction of air, so the number of parts can be reduced. Of course, it is also possible to configure it separately.

In this manner, in the aerobic fermentation drying apparatus 120 of this embodiment, water droplets are sprayed by the first circulating water equipment 171 into the housing 121 room in which the aerobically fermented material 100 is loaded, and oxygen is constantly replenished by the introduction of air from the building 110 outside the housing 121 room by the air inlet section 161, activating the aerobic microorganisms in the aerobically fermented material 100 containing the microbial attachment body 3, and the aerobic fermentation of the aerobically fermented material 100 by the aerobic microorganisms progresses.

In particular, in the aerobic fermentation drying apparatus 120 of this embodiment, the temperature, pressure, and oxygen amount are controlled by adjusting the amount of air exhausted from inside the housing 121 by the air exhaust unit 162, the amount of air introduced from outside the housing 121 by the air introduction unit 161, and the amount of air circulated inside the housing 121 by the air circulation unit 163, thereby enabling efficient aerobic fermentation treatment by maintaining an environment suitable for the activation and growth of aerobic microorganisms. In this embodiment, information on the aerobic fermentation drying apparatus 120 is managed and controlled by a computer. For example, information on at least the indoor temperature and indoor pressure of the housing 121, information on the temperature inside the building 110 outside the housing 121, information on the temperature of the air exhausted from inside the housing 121 by the air exhaust unit 162, information on the temperature of the water sprayed into the housing 121 by the first circulating water equipment 171, etc. are detected by sensors and input to the computer COMP. The information input to the computer COMP is used to control the damper 166a of the air intake section 161, the damper 166b of the air circulation section 163, the damper 166c of the air exhaust section 162, the fan 165, and the like.
This computer control allows automatic control of each process; for example, aeration control is possible in the aerobic fermentation and drying device 120, and sensors can be used to monitor temperature, humidity, oxygen concentration, or carbon dioxide concentration. This makes it possible to guarantee the quality of the final product. Not only is the control of moisture content, oxygen concentration, and process variables automated and highly efficient, but it also ensures safe, uniform processing, and records of processing for each lot are kept, making it possible to prove compliance with various local government regulations.

Here, in the fermentation process by microorganisms in the aerobic fermentation drying apparatus 120 of this embodiment, first, during the first few days, bacteria, filamentous fungi, etc. actively decompose easily decomposable organic substances in the aerobic fermentation treatment material 100, such as proteins, amino acids, and carbohydrates, raising the temperature of the aerobic fermentation treatment material 100 and, by extension, the temperature inside the housing 121. When the easily decomposable substances are consumed and the temperature becomes high, thermophilic aerobic actinomycetes, etc., become involved in the decomposition of the organic matter, and the decomposition of hemicellulose and cellulose begins, and the temperature reaches a maximum of 60°C to 80°C. This high-temperature environment kills various bacteria, thereby sanitizing the treatment material. Preferably, pathogenic bacteria are sterilized at 65°C or higher for 48 hours or more. Next, a medium temperature range of 30°C to 50°C is maintained to further promote the decomposition of the organic matter. After that, the amount of air taken in from outside the housing 121 through the air introduction section 161 is increased to promote cooling and drying.

In this way, in the aerobic fermentation drying apparatus 120 of this embodiment, decomposition and aerobic fermentation of the aerobically fermented material 100 by the aerobic microorganisms proceeds, and drying proceeds due to fermentation heat and aeration. That is, in this aerobic fermentation drying process (step S50), oxygen and the organic matter of the aerobically fermented material 100 are consumed by aerobic microorganisms such as bacteria and filamentous fungi to produce carbon dioxide and energy (heat), and the heat generated here increases the temperature of the aerobically fermented material 100, drying it.

In particular, in this embodiment, the air introduction section 161 that takes in fresh air into the housing 121 of the aerobic fermentation drying apparatus 120 takes in air from the building 110 outside the housing 121 rather than from the outside, and introduces it into the housing 121. In this embodiment, the air introduction section 161 and the air circulation section 163 are joined together to mix the air output from the upper part of the housing 121 of the air circulation section 163 with the air from the building 110 outside the housing 121, and input from the lower part of the housing 121, and the mixed air is blown and ventilated into the aerobically fermented material 100. Therefore, oxygen is evenly replenished inside the aerobically fermented material 100, and aerobic fermentation and drying proceed efficiently.

Here, the interior of the housing 121 is humidified by water spraying, and as the temperature rises due to aerobic fermentation, the air output from the upper part of the housing 121 interior through the air circulation section 163 becomes humid and hot, while the air taken in from inside the building 110 outside the housing 121 through the air introduction section 161 is relatively dry with low humidity and temperature.
Therefore, in this embodiment, the air output from the upper part of the housing 121 of the air circulation section 163 is mixed with the introduced air taken from inside the building 110 outside the housing 121, and the air is input from the lower part of the housing 121, so that the air ventilated from below to above the aerobic fermentation treatment material 100 has a relatively lower humidity than the air output from above inside the housing 121 of the air circulation section 163. Therefore, the air ventilating the aerobic fermentation treatment material 100 allows the moisture in the aerobic fermentation treatment material 100 to evaporate, i.e., promotes drying. And the amount of moisture discharged from the air discharge section 162 can be increased.

In particular, the air intake section 161 takes in air from inside the building 110 outside the housing 121, rather than outside air, so it is less susceptible to the effects of outside air temperature compared to outside air. That is, inside the highly airtight building 110, which is maintained at negative pressure to prevent odor leakage, it is possible to maintain a higher temperature than the outside air even in winter, and it is also possible to control the temperature to be less variable throughout the year compared to the outside air temperature. Therefore, even in winter, it is possible to take in relatively warm air from inside the building 110 into the housing 121 without taking in cold outside air, and even if the outside air temperature changes, the efficiency of the aerobic fermentation and drying process of the aerobic fermentation treatment material 100 loaded into the housing 121 can be maintained. That is, even in winter, the temperature difference between the open space of the air inlet 161 and the air in the air circulation section 163 can be reduced, and when the air in the air inlet 161 mixes with the air output from inside the housing 121, condensation of moisture is unlikely to occur, and evaporation of moisture in the aerobic fermentation treatment material 100, i.e., drying, can be promoted. Also, when air from inside the building 110 is taken into the housing 121 through the air inlet 161, cold outside air is not introduced, so there is little burden on the microorganisms, temperature control inside the housing 121 is easy, microbial activity is less likely to decrease, and fermentation and drying can proceed efficiently.

In the aerobic fermentation and drying apparatus 120, the aerobically fermented and dried material 200 is aerobically fermented by aerobic microorganisms and then dried by the fermentation heat and aeration (air blowing). The aerobically fermented and dried material is then relayed by a wheel loader 12 or the like and transported to the post-treatment equipment in the building 110 for the next sorting process (step S81).
As shown in Figure 4, in the post-treatment equipment of this embodiment, non-combustible material 230 and vinyl chloride 240 are removed by magnetic sorting, near-infrared sorting, etc., and the material is separated by particle size and weight into, for example, bulk density adjusting material 2 which is selected as a specified oversized heavy material, solid fuel raw material 210 which is selected as a specified oversized light material, and compost raw material 220 which is selected as a specified undersized fine material or fermentation residue fine material as microbial attached body 3.

For example, in the post-treatment equipment of this embodiment, the particles are first sorted by buoyancy caused by a predetermined air flow in a particle size and weight sorter 151 and by specific gravity, weight and particle size using a sieve with a predetermined mesh size. The air flow introduced into the sorter 151 at this time is led to a cyclone 152, where the dust is removed by dropping it downwards using a vortex, and the air from which the dust has been removed is discharged from the top of the cyclone 152. It is also effective to use a fan to suck in the output side of the cyclone 152.

This sorting machine 151 separates the waste into heavy materials of a certain size and above a certain weight, which mainly contain bulk density adjusting materials 2 such as large wood chips (wooden pieces), light materials of a certain size and below a certain weight, which mainly contain paper, plastic, etc., and fine materials under a certain size, which mainly contain decomposed food waste.

The heavy objects that are over a certain size and above a certain weight selected by the sorting machine 151 mainly contain bulk density adjusting materials 2 such as large wood chips, so after removing non-combustible materials 230 such as iron, magnetism, etc. by magnetic sorting using a magnetic sorting machine 153 or by manual sorting, the objects are returned to the mixing yard Y3 and reused as bulk density adjusting materials 2.
Furthermore, the fine granules of a certain size below the specified size selected by the sorter 151 are subjected to magnetic sorting by the magnetic sorter 153 to remove incombustible materials 230 such as iron and magnetism, and are then used as the compost raw material 220 and/or the fermentation residue fine granules, which are microorganism-attached material 3. That is, they may be used as the compost raw material 220, or, since the fermentation residue fine granules have many aerobic microorganisms attached thereto, they may be returned to the mixing yard Y3 and used as the microbial-attached material 3 for seed culture.
Furthermore, since the lightweight objects sorted by the sorter 151, which are of a specified size but less than a specified weight, contain paper, plastic, etc., the vinyl chloride 240 is removed by infrared sorting using the infrared sorter 154, and then the objects are turned into solid fuel production raw material 210.

In the solid fuel production process, the solid fuel raw material 210 is mixed with a calorific value adjusting material such as dry plastic, wood, paper, cloth, etc., crushed in a crusher, and non-combustible materials 230 such as iron and stone are removed. The solid fuel is then molded in a molding machine to produce solid fuel 211. In the molding process, additives such as anti-corrosion agents are added as necessary. The odors, water vapor, etc. generated in the solid fuel production process, especially in the molding process, are sent to a biological deodorizing device 140, where they are deodorized and then exhausted to the outside.
The solid fuel 211 thus formed has excellent transportability and storability, is easy to handle as a fuel, and can be used for multiple purposes (heating, power generation, etc.).
The solid fuel source 210 can be compressed and packed using a baler (compression packing machine) to facilitate transportation to the solid fuel production process.
In addition, the compost raw material 220 is matured in a separate maturation bed for several days to several weeks while being watered and aerated, as in the aerobic fermentation and drying described above, and then it is sifted according to the purpose and conditions of use, and further matured if necessary, to obtain high-quality compost 221.

In the waste treatment plant of this embodiment, the amount of air discharged from the housing 121 chamber of the air discharge section 162 is set to be greater than the amount of air input into the housing 121 chamber of the air introduction section 161 and the air circulation section 163 in the fermentation drying device 120, and the housing 121 chamber is maintained at negative pressure, eliminating the possibility of odors escaping outside the housing 121 chamber. However, the air (odor) discharged from the housing 121 chamber of the air discharge section 162 is deodorized by the biological deodorization device 140 before being exhausted to the outside.

In particular, in the waste treatment plant of this embodiment, the air exhaust section 162 that forms an air passage for the air exhausted from within the housing 121 is connected to the air plenum chamber 130, and the air from within the building 110 outside the housing 121 is also introduced into the air plenum chamber 130, where the air exhausted from within the housing 121 is mixed with the air from within the building 110 outside the housing 121. The indoor air from the air plenum chamber 130 is then sent to the biological deodorization device 140.

In the waste treatment plant of this embodiment, a damper 136A and a fan (not shown) are provided in the path for introducing air from inside the building 110 outside the housing 121 into the air plenum chamber 130, so that the amount of air from inside the building 110 that enters the air plenum chamber 130 can be adjusted. Also, the amount of air discharged from inside the housing 121 that enters the air plenum chamber 130 can be adjusted by the damper 166c. By adjusting both of these, the humidity in the air plenum chamber 130 can be controlled to be below a predetermined level.
A fan 135 and a damper 136B are provided in the air path from the air plenum chamber 130 to the biological deodorizer 140, and the air from the air plenum chamber 130 is pressurized by the fan (blower) 135 and fed to the biological deodorizer 140, and the amount of air fed from the air plenum chamber 130 to the biological deodorizer 140 can be adjusted by the damper 136C. The fan that guides air from inside the building 110 to the air plenum chamber 130 and the fan 135 that guides air from the air plenum chamber 130 to the biological deodorizer 140 may be inverter-controlled to control the rotation speed so that the rotation speed can be reduced as necessary for energy-saving operation.

When implementing the present invention, if necessary, a scrubber device 137 may be provided midway along the path from the air plenum chamber 130 to the biological deodorizer 140 to remove harmful substances and the like contained in the air from the air plenum chamber 130 before supplying the air to the biological deodorizer 140. Furthermore, a chemical deodorizer may also be provided. In the chemical deodorizer, the gas is forced to pass through a filter medium, where water-soluble compounds contained in the gas are dissolved and absorbed by the moist biofilm covering the filter medium. The biofilm is a thin layer composed of water, polysaccharides, substances resulting from the bacterial ecosystem, and substances derived from microorganisms. When the gas in the airflow enters the biofilm, the pollutants come into contact with the microorganisms and the compounds are decomposed.

The biological deodorizing device (biofilter device) 140 constituting the deodorizing equipment into which air is introduced from the air plenum chamber 130 is usually installed outside the building 110, and is configured by stacking and housing a biofilter 142 made of a carrier having aerobic microorganisms attached thereto or on which aerobic microorganisms exist in a natural state, such as wood chips, a compost bed, soil, or beets, in a housing tank 141 with an open top. The biofilter 142 is preferably made of wood chips, which have hygroscopic and moisture-regulating properties and can ensure ventilation by being packed in a predetermined size and shape.
Specifically, in the biological deodorizing device 140, a floor material 143 having ventilation holes is installed at a position at a predetermined height from the bottom of the storage tank 141 to divide the space into upper and lower parts, and carriers such as wood chips are piled up on the floor material 143 to form a biofilter 142. Air from the air plenum chamber 130 is introduced into the lower space divided by the floor material 143 below the storage tank 141, passes through the ventilation holes in the floor material 143, flows from bottom to top through the biofilter 142 on which carriers such as wood chips are piled up, and is released into the atmosphere from above the storage tank 141.

As the air input from below the storage tank 141 passes through the biofilter 142 from bottom to top, the odorous components contained in the air are consumed (decomposed and digested) through aerobic fermentation by aerobic microorganisms attached to the carriers, such as wood chips, of the biofilter 142.

In this way, the odor-laden air exhausted from the aerobic fermentation drying apparatus 120 is mixed with the intake air taken in from inside the building 110 in the air plenum chamber 130, and then input into the biological deodorization apparatus (biofilter apparatus) 140, where it is biologically deodorized by the biofilter 172, and then released into the atmosphere.
In addition, in the biological deodorization device 140, which performs deodorization through digestion by biological treatment by such aerobic microorganisms, the foul-smelling gas exhausted from the aerobic fermentation drying device 120 is decomposed into harmless substances such as _CO2 and _H2O , and inorganic ions such as _SO4- ^and _NO3- ^, and then released.At this time, no residue that requires post-treatment is generated, and the gas is not incinerated, so emissions of _CO2 and _NOx are kept to a minimum.

At this time, in the biological deodorizing device (biofilter device) 140, water is sprayed from above the storage tank 141 onto the biofilter 142, which is made up of an accumulation of carriers such as wood chips. This allows the moisture necessary for the activity and growth of aerobic microorganisms attached to carriers such as wood chips that decompose and consume the odors input from below the storage tank 141 to be uniformly added and replenished, resulting in stable deodorizing efficiency.

In particular, in this embodiment, excess water from watering is collected and reused for watering again. That is, in this embodiment, a second circulating water system 181 is formed that collects excess water that is sprayed from above the storage tank 141 and falls to the bottom, and sprays it again from above the storage tank 141.

Within the storage tank 141, excess water from watering flows down through the passage holes in the floor material 143 into the space below the floor material, from there it is discharged outside the storage tank 141 and collected in the water storage tank 183, and is pressurized from the water storage tank 183 by a pump or the like to a spray nozzle installed on the upper side of the storage tank 141, and is sprayed as water droplets from the spray nozzle onto the biofilter 142.
In addition, the second circulating water system 181 is designed so that water from the outside, such as industrial water or drinking water, can be replenished into the water storage tank 183 via a valve or the like.
In this embodiment, in cases where the amount of water supplied to be sprayed into the housing 121 chamber in the first circulating water equipment 171 is insufficient, water collected in the water storage tank 183 of the second circulating water equipment 181 can be supplied to the water storage tank 173A of the first circulating water equipment 171 via a supply path 174 equipped with a valve or the like.

In this way, the second circulating water equipment 181 supplies water to the biofilter 172 by sprinkling, and the surplus water from the sprinkling is discharged, collected and reused for sprinkling on the biofilter 172, thereby making it possible to replenish the moisture necessary for the fermentation and growth of aerobic microorganisms in the biofilter 172 and to equalize the moisture supply, thereby obtaining stable deodorization treatment efficiency. In particular, since the surplus water from the sprinkling that has passed through the biofilter 172 and been collected contains aerobic microorganisms, the water that is sprayed as water droplets also contains aerobic microorganisms, thereby distributing the aerobic microorganisms uniformly on the biofilter 172 and improving the digestion efficiency by aerobic fermentation. In other words, the spraying of water droplets also moves the aerobic microorganisms from top to bottom, enabling efficient odor treatment.
Furthermore, since excess water from sprinkling is collected and reused, the moisture required by aerobic microorganisms for stable deodorizing efficiency can be provided at low cost, and since excess water from sprinkling is not discharged to the outside, purification for drainage can be eliminated.

In addition, the water that falls into the space between the floor material 143 and the bottom surface in the storage tank 141 may be discharged by sucking it up with a pump or the like when a predetermined amount is collected and collected in the water storage tank 183, or it may be made to flow to the water storage tank 183 side when a predetermined amount of wastewater is accumulated. In addition, here, the number of parts can be reduced by providing a path for air that is input into the space between the floor material 143 and the bottom surface in the storage tank 141 and enters the biofilter 172 through the air vents in the floor material 143, and a path for water that is sprayed on the biofilter 172 and falls into the space between the floor material 143 and the bottom surface through the air vents in the floor material 143, but it is also possible to configure it separately.

In particular, in this embodiment, as described above, the air discharged from inside the housing 121 of the aerobic fermentation drying device 120 by the air discharge section 162 is mixed with the air outside the housing 121 in the air plenum chamber 130 and then input into the biological deodorization device 140, from where it is exhausted to the outside air.

Here, the interior of the housing 121 of the aerobic fermentation drying device 120 is humidified by water spraying, and the temperature rises due to aerobic fermentation, so the air in the air exhaust section 163 that is discharged from the top of the interior of the housing 121 and input into the air plenum chamber 130 becomes hot and humid, while the air in the building 110 outside the housing 121 that is separately input into the air plenum chamber 130 is relatively dry with low humidity and temperature.

Therefore, in the waste treatment plant of this embodiment, the air discharged from the air exhaust section 162 from the upper part of the housing 121 room is mixed with the air inside the building 110 outside the housing 121 room in the air plenum chamber 130, so that the air supplied from the air plenum chamber 130 to the biological deodorization device 140 can be made to have a relatively lower humidity and temperature than the air discharged from the air exhaust section 162 from the upper part of the housing 121.

As a result, in the mixed air in which the humidity has been reduced in the air plenum chamber 130, the humidity in the air is less likely to condense in the biological deodorizer 140 to which it is input, and the moisture from the humidity discharged from inside the housing 121 is less likely to be generated as exhaust water in the biological deodorizer 140 and remain as moisture in the second circulating water equipment 181, making it easier for the amount of moisture from the humidity discharged from inside the housing 121 to be released into the atmosphere. In other words, the amount of moisture released into the atmosphere can be increased.

Therefore, in the waste treatment plant of this embodiment, the first circulating water equipment 171 and the second circulating water equipment 172 are configured to prevent moisture from accumulating, and the moisture from the wastes 1A and 1B can be released into the atmosphere and consumed without the need for special wastewater purification equipment, making it possible to reduce the energy costs of wastewater treatment.

Furthermore, the building 110 is usually constructed with poor ventilation to prevent odors, so it is less susceptible to the effects of outside air temperatures even in winter. However, the air plenum chamber 130 takes in air from inside the building 110 instead of outside air, which prevents the temperature of the air introduced into the air plenum chamber 130 from dropping even in winter. This reduces the load on the aerobic microorganisms contained in the biofilter 142 of the biological deodorizer 140 to which the mixed air from the air plenum chamber 130 is supplied, and prevents a decrease in deodorizing efficiency. In other words, by suppressing temperature changes in the mixed air from the air plenum chamber 130 without being significantly affected by changes in outside air temperature, the load on the aerobic microorganisms in the biofilter 142 is reduced, and deodorizing efficiency can be stabilized.

In this way, in the waste treatment plant of this embodiment, the high-water content methane fermentation target material 10B, which is a part of the wastes 1A and 1B and mainly contains food waste, is subjected to methane fermentation to generate biogas G, and the slurry-like methane fermentation residue 150 obtained after methane fermentation of the methane fermentation target material 10B is combined with the remaining sorting residue 10A of the wastes 1A and 1B without solid-liquid separation, and a bulk density adjusting material 2 and a microbial attachment body 3 are added to form an aerobic fermentation target material 100, which is aerobically fermented and dried by the fermentation heat and ventilation to generate solid fuel material 210 and/or compost material 210, and the moisture is exhausted as steam.

In a system in which the slurry-like methane fermentation residue 150 is collected together with the remaining wastes 1A and 1B, i.e., the low-water content solid sorting residue 10A, and then bulk density adjusting material 2 and microbial attachment material 3 are added to perform aerobic fermentation, there is an abundance of organic matter in the sorting residue 10A and residual organic matter in the methane fermentation residue 150, and there is also moisture from the slurry-like methane fermentation residue 150. Furthermore, the addition of bulk density adjusting material 2 ensures ventilation even when the material is piled up, preventing oxygen deficiency due to insufficient ventilation in the aerobically fermented material 100 and suppressing the movement of anaerobic bacteria, so that the aerobic microorganisms in the microbial attachment material 3 are activated and become dominant and active, and aerobic fermentation progresses. Therefore, the moisture in the aerobically fermented material 100 can be evaporated by the fermentation heat without the need for external heating energy.

In addition, in the aerobic fermentation drying apparatus 120 that aerobically ferments the aerobically fermented material 100, an air circulation section 163 is formed that draws in air from above inside the housing 121 room and expels it as compressed air from below, and the air drawn in from above inside the housing 121 room is blown to the aerobically fermented material 100 together with the introduced air taken in from inside the building 110 outside the housing 121 room by the air introduction section 161, and the progress of aerobic fermentation and drying is promoted by the ventilation that pressurizes the air to the aerobically fermented material 100. In particular, the air circulation section 163 creates an air passage through which air flows from the bottom to the top in the aerobically fermented material 100 piled up inside the housing 121 of the aerobic fermentation drying device 120, and prevents uneven distribution of aerobic fermentation by equalizing the supply of air and oxygen to the aerobically fermented material 100 without stirring the aerobically fermented material 100, improving the processing efficiency of the aerobic fermentation and drying of the entire aerobically fermented material 100.

In this way, according to the waste treatment plant of this embodiment, the slurry-like methane fermentation residue 150 is mixed with the remaining selected residue 10A obtained by selecting the methane fermentation treatment target 10B from the wastes 1A and 1B without dehydrating it, and by further adding the bulk density adjusting material 2 and the microbial adhesion material 3, it is possible to ferment it aerobically, evaporate the water with the fermentation heat, and release it into the atmosphere via the deodorizing device 140. Since there is no need for purification equipment to purify the water in the methane fermentation residue 150 and drain it (discharge it), or heating equipment to heat and dry it, the facility operating costs and energy costs can be reduced, and the wastes 1A and 1B can be recycled (reused) with low energy and low cost.

Furthermore, in the waste treatment plant of this embodiment, the first circulating water equipment 171 collects wastewater that seeps out from the aerobically fermented material 100 in the aerobic fermentation drying apparatus 120 where the aerobically fermented material 100 is aerobically fermented, and after filtering with a filter 172 to remove foreign matter, the water is sprayed onto the aerobically fermented material 100 being aerobically fermented in the aerobic fermentation drying apparatus 120. This makes it possible to uniformly supply moisture required by the aerobic microorganisms in the aerobically fermented material 100, prevents uneven distribution of aerobic fermentation, and improves the processing efficiency of aerobic fermentation and drying.
In addition, the wastewater from the aerobic fermentation drying apparatus 120 is not discharged to the outside, and no purification is provided for the discharged water. That is, the first circulating water equipment 171 has first water storage tanks 173A, 173B in which water recovered from the aerobic fermentation drying apparatus 120 is stored and which can be replenished with water from the outside, and the first circulating water equipment 171 and the second circulating water equipment 181 are provided with a supply path 175 which can freely supply water from the second water storage tank 183 to the first water storage tanks 173A, 173B, and when the water in the first water storage tanks 173A, 173B is insufficient or becomes small, it is sufficient to replenish it from the second water storage tank 183 or from the outside, so that the supply of water from the outside is minimized, excess water storage is prevented, costs are reduced, and purification for the discharged water is not required.

In particular, in the waste treatment plant of this embodiment, the air circulation section 163, which sucks in air from above inside the housing 121 room of the aerobic fermentation drying device 120 and blows it from below inside the housing 121 room to circulate it, and the air introduction section 161, which takes in air from inside the building 110 into the housing 121 room, join together, and the mixed air of the air sucked in from above inside the housing 121 room by the air circulation section 163 and the introduced air taken in from inside the building 110 outside the housing 121 room by the air introduction section 161 is blown from below inside the housing 121 room to the aerobic fermentation treatment material 100.

Therefore, according to the waste treatment plant of this embodiment, the high humidity air sucked in from above inside the housing 121 and circulated by the air circulation section 163 is mixed with the introduced air taken in from inside the building 110 outside the housing 121 by the air introduction section 161 to relatively reduce the humidity, and the mixed air with reduced humidity is supplied to the aerobically fermented material 100 from below inside the housing 121 and passes from the bottom to the top of the aerobically fermented material 100. Therefore, the air passed through the aerobically fermented material 100 is more likely to vaporize the moisture in the aerobically fermented material 100. Therefore, the processing efficiency of drying the aerobically fermented material 100 can be improved.

Furthermore, in the waste treatment plant of this embodiment, the air introduced into the housing 121 of the aerobic drying, fermenting, and drying apparatus 120 through the air introduction section 161 is not outside air, but air from inside the building 110, which is kept at negative pressure to increase airtightness and prevent odor leakage. Therefore, even when the outside temperature is low, such as in winter, relatively high temperature air is maintained without cold air being introduced into the housing 121 through the air introduction section 161, preventing condensation from occurring due to mixing with the air from the air circulation section 163, and maintaining the efficiency of moisture evaporation, i.e., the drying efficiency.

Therefore, according to the waste treatment plant of this embodiment, high processing efficiency is maintained for drying the aerobic fermentation treatment material 100, and even if the amount of waste 1A, 1B being treated is large, the configuration makes it easy to evaporate the water, preventing excess water from accumulating in the first circulating water equipment 171, and eliminating the need for purification for drainage.

In addition, in the waste treatment plant of this embodiment, the second circulating water equipment 181 collects excess water sprayed on the biofilter 142 containing aerobic microorganisms of the deodorizing device 140 and reuses it for spraying, so the water sprayed on the deodorizing device 140 is not discharged to the outside, minimizing the need to replenish water from the outside, preventing excess water from accumulating, and eliminating the need for purification for drainage. That is, the second circulating water equipment 181 has a second water storage tank 183 that contains the water collected from the deodorizing device 140 and can also replenish water from the outside, and when the water in the second water storage tank 183 is low or running low, it can be replenished from the outside, minimizing the need to replenish water from the outside, preventing excess water from accumulating, reducing costs, and eliminating the need for purification for drainage.

In particular, in the waste treatment plant of this embodiment, the air discharged from inside the housing 121 of the aerobic fermentation drying apparatus 120 is mixed with the introduced air taken in from inside the building 110 in the air plenum chamber 130, and then supplied to the biological deodorization apparatus 140, where it is biologically deodorized and exhausted to the outside.
Here, the air discharged from the upper part of the housing 121 of the air discharge part 162 inputted into the air plenum chamber 130 becomes humid air as the inside of the housing 121 is humidified by water spraying and the temperature becomes high. On the other hand, the air inside the building 110 outside the housing 121 inputted separately into the air plenum chamber 130 is relatively low humidity and dry air.
Therefore, in this embodiment, the air discharged from inside the housing 121 of the air discharge section 162 and the air outside the housing 121 within the building 110 are mixed in the air plenum chamber 130, so that the air pressurized from the air plenum chamber 130 to the biological deodorization device 140 has a relatively lower humidity than the air discharged from inside the housing 121 of the air discharge section 162.

That is, according to the waste treatment plant of this embodiment, the high humidity air discharged from inside the housing 121 is mixed with the introduced air taken from inside the building 110 outside the housing 121 in the air plenum chamber 130 to relatively reduce the humidity, and the mixed air with reduced humidity is supplied to the biological deodorization device 140 and passed from bottom to top of the biofilter 142 to be exhausted to the outside. This prevents the humidity of the air discharged from inside the housing 121 from being discharged as condensed water (exhaust water) inside the biological deodorization device 140, and increases the amount of moisture released to the outside air. This prevents excessive moisture from accumulating in the second circulating water facility 181 which handles the moisture in the biological deodorization device 140.
That is, according to the waste treatment plant of this embodiment, even if the amount of waste 1A, 1B being treated is large, the configuration makes it easy to exhaust moisture into the atmosphere, preventing excess moisture from being accumulated in the second circulating water equipment 181 and eliminating the need for purification for drainage.

In this embodiment, the moisture is dried by the fermentation heat and ventilation due to aerobic fermentation, and the moisture is prevented from being discharged as exhaust water in the biological deodorization device 141 and the second circulating water equipment 181, and the amount of moisture released into the atmosphere is increased, so that the moisture from the wastes 1A and 1B can be dried and removed, and wastewater is less likely to accumulate. Therefore, by easily releasing the moisture from the wastes 1A and 1B into the atmosphere, even when a large amount of wastes 1A and 1B is treated, moisture is less likely to accumulate within the plant, making it possible to eliminate the need for drainage equipment to discharge the moisture from the wastes 1A and 1B to the outside, and the wastes 1A and 1B can be effectively used to produce biogas G and recycled materials (solid fuel 211 and/or compost 221) at low energy costs.

As explained above, the waste treatment plant of this embodiment separates waste 1A into high-water content methane fermentation target material 10B to be subjected to methane fermentation and the remaining low-water content selected residue 10A, and also includes a pretreatment facility consisting of a crusher 14 and a mixing adjustment tank 19, etc., which prepares the methane fermentation target material 10B into a slurry-like state, a methane fermentation facility consisting of a methane fermentation tank 21, etc., which ferments the slurry-like methane fermentation target material 10B into methane to produce biogas G, and a methane fermentation residue 150 in the form of a slurry after methane fermentation of the methane fermentation target material 10B is mixed with the selected residue 10A separated in the pretreatment facility, and further bulked up. The system is equipped with a mixing section Y3 that adds bulk density adjusting material 2 such as wood chips and microbial-attached material 3 such as fine aerobic fermentation residue particles with aerobic microorganisms attached thereto to prepare aerobically fermented material 100 to be subjected to aerobic fermentation, an aerobic fermentation drying equipment that includes an aerobic fermentation drying device 120 that aerobically ferments and dries the aerobic fermentation treated material 100, and a post-processing equipment that includes a particle size and weight sorter 151, a magnetic sorter 153, an infrared sorter 154, etc. that removes non-combustible material 230 and vinyl chloride 240 from the aerobic fermentation dried material 200 after aerobic fermentation and drying of the aerobic fermentation treated material 100, and sorts the solid fuel material 210 and/or compost material 220.

Therefore, in the waste treatment plant of this embodiment, a part of the waste 1A, i.e., the high-water content methane fermentation target material 10B, is subjected to methane fermentation to produce biogas G that can be converted into energy such as heat and electricity, and the methane fermentation residue 110 after methane fermentation is mixed with the rest of the waste 1A, i.e., the low-water content solid sorting residue 10A, the bulk density adjusting material 2, and the microbial attachment material 3 to produce the aerobically fermented target material 100, which is then aerobically fermented and dried to produce the solid fuel material 210 and/or compost material 220.

In particular, according to the waste treatment plant of this embodiment, after the methane fermentation of the slurry-like methane fermentation target material 10B that has been selected and conditioned from the waste 1A, the slurry-like methane fermentation residue 110 is mixed with the low-water content selection residue 10A remaining after the selection of the methane fermentation target material 10B from the waste 1A, and is aerobically fermented with the addition of bulk density adjusting material 2 and microbial attachment material 3 to increase the volume. That is, the slurry-like methane fermentation residue 110 is mixed with the selection residue 10A, bulk density adjusting material 2 and microbial attachment material 3 to form the aerobically fermented target material 100, which is then aerobically fermented.

In this way, in the aerobically fermented material 100, which is a mixture of slurry-like methane fermentation residue 110 with the remaining sorted residue 10A from the waste 1A, bulk density adjuster 2, and microbial adhesion body 3, the residual organic matter in the methane fermentation residue 110 and the organic matter in the sorted residue 10A provide the amount of decomposable organic matter and appropriate moisture required for the proliferation of aerobic microorganisms. In addition, the mixing of bulk density adjuster 2, which increases the bulk, ensures a certain amount of voids within the pile of the aerobically fermented material 100, providing good ventilation and an even supply of oxygen. Therefore, the activity of anaerobic microorganisms is suppressed, and the aerobic microorganisms attached to the microbial attachment material 3 mixed with the aerobically fermented material 100 predominate and operate actively, progressing the aerobic fermentation, and the fermentation heat from the aerobic fermentation can evaporate the water content of the aerobically fermented material 100 containing the slurry-like methane fermentation material 10B and dry it without adding heating energy from the outside. In addition, in this embodiment, the aerobic fermentation and drying progress at a high rate by blowing air through the aerobically fermented material 100, and the aerobic fermentation and drying progress efficiently.

Thus, according to the waste treatment plant of this embodiment, the slurry-like methane fermentation residue 110 is mixed with the sorting residue 10A, the bulk density adjusting material 2, and the microbial adhering material 3 to create the aerobic fermentation treatment material 100, which is then aerobically fermented, and the moisture in the slurry-like methane fermentation residue 110 can be dried (evaporated) by the fermentation heat and aeration (air blowing) of the aerobic fermentation. Therefore, the moisture in the slurry-like methane fermentation residue 110 can be dried and removed without adding heating energy, making it possible to recycle the wastes 1A and 1B through fermentation treatment without having a purification device for purifying wastewater and a heating and drying device. In other words, the wastes 1A and 1B can be effectively used as biogas G and resources (solid fuel material 210 and/or compost material 220) while reducing energy costs.

Furthermore, the waste treatment plant of this embodiment is equipped with a first circulating water facility 171 that collects wastewater discharged from the aerobic fermentation drying device 120 in which the aerobically fermented material 100 is aerobically fermented, filters it with a filter 172 to remove foreign matter, and then sprays the aerobically fermented material 100 being aerobically fermented in the aerobic fermentation drying device 120.

That is, according to the waste treatment plant of this embodiment, the wastewater seeping out from the aerobically fermented material 100 in the aerobic fermentation drying device 120 is not discharged as exhaust water, but rather foreign matter is removed by the filter 142 and then sprayed onto the aerobically fermented material 100. In addition, the wastewater discharged from the aerobic fermentation drying device 120, including the surplus water from the spraying, is collected and reused for spraying. This makes it possible to equalize the supply of water to the aerobically fermented material 100 being aerobically fermented in the aerobic fermentation drying device 120, thereby preventing uneven distribution of aerobic fermentation and improving the processing efficiency of aerobic fermentation and drying. Furthermore, the wastewater from the aerobic fermentation drying device 120 is not discharged to the outside, and purification for drainage is not required.

The waste treatment plant of this embodiment further includes a biological deodorizing device 140 as a deodorizing facility that biologically deodorizes the air discharged from the aerobic fermentation drying device 120 in which the aerobic fermentation treatment material 100 is aerobically fermented and exhausts it to the outside, and a second circulating water facility 181 that sprays water on a biofilter 142 made of a pile of carriers such as wood chips containing aerobic microorganisms in the biological deodorizing device 140, collects excess water from the spraying, and reuses it for spraying the biofilter 142 again.

Therefore, according to the waste treatment plant of this embodiment, the odor-containing air discharged from the aerobic fermentation drying apparatus 120, which aerobically ferments the aerobic fermentation treatment material 100, is deodorized by the biological deodorization apparatus 140 and then exhausted to the outside, so that odors are not discharged to the outside.
In particular, the second circulating water equipment 181 supplies moisture by spraying water onto the biofilter 142, which is made up of an accumulation of wood chips and the like to which aerobic microorganisms are attached, of the biological deodorizing device 140, which biologically deodorizes the odorous air discharged from the aerobic fermentation drying device 120, so that the moisture supply to the biofilter 142 can be made uniform. Furthermore, by recovering excess water from the spraying without discharging it as exhaust water and repeatedly reusing it for spraying, the aerobic microorganisms in the biofilter 142 can be moved and the distribution of the aerobic microorganisms can be made uniform, thereby obtaining a stable deodorizing efficiency of odorous components.
In addition, since surplus water from watering is not discharged as exhaust water, purification for drainage is not required, and low costs can be achieved.

The waste treatment plant of this embodiment further includes an air plenum chamber 130 in which air discharged from an aerobic fermentation drying device 120 serving as an aerobic fermentation drying equipment that aerobically ferments the aerobic fermentation treatment material 100 and air having a lower relative humidity than the air discharged from the aerobic fermentation drying device 120 are input and mixed, and the mixed air is output to a biological deodorization device 140 serving as a deodorization equipment.

Therefore, according to the waste treatment plant of this embodiment, the air discharged from the aerobic fermentation drying device 120 is mixed with dry air with a lower relative humidity in the air plenum chamber 130 to reduce the humidity, and then biologically deodorized in the biological deodorization device 140 and exhausted to the outside. Therefore, the water vapor exhausted from the aerobic fermentation drying device 120 is less likely to be exhausted as exhaust water within the biological deodorization device 140, and the amount of moisture exhausted to the outside can be increased. Therefore, excessive moisture is less likely to accumulate in the biological deodorization device 140 and the second circulating water equipment 181, making it possible to eliminate the need for a drainage facility.

The waste treatment plant of this embodiment further includes a cogeneration facility 33 that refines the biogas G and then uses it as fuel to supply heat and electricity, so that the biogas G can be used more efficiently as an energy source. In particular, the waste heat can be extracted as hot water or steam and used to heat or keep warm the methane fermentation tank 21, which serves as a methane fermentation facility, so that the costs of heating or keeping warm the methane fermentation tank 21 can be reduced.

In addition, in the above embodiment, waste 1A is separated into a high-water content methane fermentation target material 10B to be subjected to methane fermentation and a low-water content selection residue 10A. The methane fermentation target material 10B is prepared into a slurry-like form in a pretreatment process consisting of a crushing process (step S11), a separation process (step S12) and a moisture adjustment process (step S13). The slurry-like methane fermentation target material 10B is subjected to methane fermentation to generate biogas G in a methane fermentation process (step 20). The slurry-like methane fermentation residue 150 after methane fermentation of the methane fermentation target material 10B is mixed with the selection residue 10A separated in the separation process (step S12). It can also be considered as an invention of a waste treatment method that includes a mixing step (step S40) in which a bulk density adjusting material 2 such as wood chips for bulking and a microbial-attached material 3 such as fine aerobic fermentation residue particles with aerobic microorganisms attached thereto are added to prepare an aerobically fermented material 100 to be subjected to aerobic fermentation, an aerobic fermentation drying step (step S50) in which the aerobically fermented material 100 is aerobically fermented and dried, and a post-treatment step (step S81) in which non-combustible material 230 and vinyl chloride 240 are removed from the aerobically fermented and dried aerobically fermented and dried material 200 of the aerobically fermented material 100, and the solid fuel material 210 and/or compost material 220 are selected.

In the waste treatment method of this embodiment, a part of the waste 1A, i.e., the high-water content methane fermentation target material 10B, is subjected to methane fermentation to produce biogas G that can be converted into energy such as heat and electricity, and the methane fermentation residue 110 after methane fermentation is mixed with the rest of the waste 1A, i.e., the low-water content solid sorting residue 10A, the bulk density adjusting material 2, and the microbial attachment material 3 to produce the aerobically fermented target material 100, which is then aerobically fermented and dried to produce the solid fuel material 210 and/or compost material 220.

In particular, according to the waste treatment method of this embodiment, after the methane fermentation of the slurry-like methane fermentation target material 10B that has been selected and conditioned from the waste 1A, the slurry-like methane fermentation residue 110 is mixed with the low-water content selection residue 10A remaining after the selection of the methane fermentation target material 10B from the waste 1A, and is aerobically fermented with the addition of bulk density adjusting material 2 and microbial attachment material 3 to increase the volume. That is, the slurry-like methane fermentation residue 110 is mixed with the selection residue 10A, bulk density adjusting material 2 and microbial attachment material 3 to form the aerobically fermented target material 100, which is then aerobically fermented.

In this way, in the aerobically fermented material 100, which is a mixture of slurry-like methane fermentation residue 110 with the remaining sorted residue 10A from the waste 1A, bulk density adjuster 2, and microbial adhesion body 3, the residual organic matter in the methane fermentation residue 110 and the organic matter in the sorted residue 10A provide the amount of decomposable organic matter and appropriate moisture required for the proliferation of aerobic microorganisms. In addition, the mixing of bulk density adjuster 2, which increases the bulk, ensures a certain amount of voids within the pile of the aerobically fermented material 100, providing good ventilation and an even supply of oxygen. Therefore, the activity of anaerobic microorganisms is suppressed, and the aerobic microorganisms attached to the microbial attachment material 3 mixed with the aerobically fermented material 100 predominate and operate actively, progressing the aerobic fermentation, and the fermentation heat from the aerobic fermentation can evaporate the water content of the aerobically fermented material 100 containing the slurry-like methane fermentation material 10B and dry it without adding heating energy from the outside. In addition, in this embodiment, the aerobic fermentation and drying progress at a high rate by blowing air through the aerobically fermented material 100, and the aerobic fermentation and drying progress efficiently.

Thus, according to the waste treatment method of this embodiment, the slurry-like methane fermentation residue 110 is mixed with the sorting residue 10A, the bulk density adjusting material 2, and the microbial adhering material 3 to create the aerobic fermentation treatment material 100, which is then aerobically fermented, and the moisture in the slurry-like methane fermentation residue 110 can be dried (evaporated) by the fermentation heat of the aerobic fermentation and aeration (air blowing). Therefore, the moisture in the slurry-like methane fermentation residue 110 can be dried and removed without adding heating energy, making it possible to recycle the wastes 1a and 1b through fermentation treatment without having a purification device for purifying wastewater and a heating and drying device. In other words, the wastes 1a and 1b can be effectively used as biogas G and resources (solid fuel material 210 and/or compost material 220) while reducing energy costs.

Furthermore, in the waste treatment method of this embodiment, wastewater (leachate) seeping out from the aerobically fermented material 100 undergoing aerobic fermentation in the aerobic fermentation drying process (step S50) is collected, filtered with a filter 172 to remove foreign matter, and then sprayed onto the aerobically fermented material 100.

According to the waste treatment method of this embodiment, the wastewater that seeps out from the aerobically fermented material 100 in the aerobic fermentation drying device 120 is not discharged as exhaust water, but is sprayed on the aerobically fermented material 100 after removing foreign matter with a filter 142, and the wastewater discharged from the aerobic fermentation drying device 120, including the surplus water from the spraying, is collected and reused for spraying. Therefore, it is possible to equalize the supply of water to the aerobically fermented material 100 that is being aerobically fermented in the aerobic fermentation drying device 120, preventing uneven distribution of aerobic fermentation and improving the processing efficiency of aerobic fermentation and drying. Furthermore, the wastewater that seeps out from the aerobically fermented material 100 is not discharged to the outside, and purification for drainage is not required.

The waste treatment method of this embodiment further includes a deodorization process (step S70) in which the air discharged from inside the housing 121 of the aerobic fermentation drying device 120 that aerobically ferments the aerobic fermentation treatment material 100 in the aerobic fermentation drying process (step S50) is biologically deodorized and exhausted to the outside. In the deodorization process (step S70), water is sprayed onto the biofilter 142 that performs biological deodorization, and the excess water is collected and reused for spraying the biofilter 142 again.

Therefore, according to the waste disposal method of this embodiment, the odor-containing air discharged from within the housing 121 of the aerobic fermentation drying apparatus 120, which aerobically ferments the aerobically fermented material 100, is deodorized by the biological deodorization apparatus 140 and then exhausted to the outside, so that odors are not discharged to the outside.
In particular, in the deodorization process (step S70), moisture is supplied by spraying water onto the biofilter 142, which is made up of an accumulation of wood chips and the like to which aerobic microorganisms are attached, of the biological deodorization device 140, which biologically deodorizes the odorous air discharged from within the housing 121 of the aerobic fermentation drying apparatus 120. This makes it possible to uniformly supply moisture to the biofilter 142. Furthermore, by recovering excess water from the spraying without discharging it as exhaust water and repeatedly reusing it for spraying, the aerobic microorganisms in the biofilter 142 can be moved and the distribution of the aerobic microorganisms can be uniformed, thereby obtaining a stable deodorization efficiency of odorous components.
In addition, since surplus water from watering is not discharged as exhaust water, purification for drainage is not required, and low costs can be achieved.

Furthermore, the waste treatment method of this embodiment has an exhaust adjustment process (step S60) between the aerobic fermentation drying process (step S50) and the deodorization process (step S70) in which the air exhausted from the housing 121 room where the aerobically fermented material is being aerobically fermented is mixed with air having a lower relative humidity than the exhausted air, and in the deodorization process (step S70), the air mixed in the exhaust adjustment process (step S60) is biologically deodorized and exhausted to the outside.

Therefore, according to the waste treatment method of this embodiment, the humid air discharged from the housing 121 of the aerobic fermentation drying device 120, which aerobically ferments and dries the aerobic fermentation treatment material 100, is mixed with low humidity air, thereby relatively reducing the humidity and providing deodorization, so that the water vapor exhausted from the housing 121 is less likely to be discharged as exhaust water in the biological deodorization device 140, which performs biological deodorization, and the amount of moisture exhausted to the outside can be increased. Therefore, excessive moisture is less likely to accumulate in the biological deodorization device 140 and the second circulating water equipment 181, making it possible to eliminate the need for a drainage facility.

In addition, according to the waste treatment method of this embodiment, a biogas utilization process (step S32) is further provided in which the biogas G is refined and then used as fuel to supply heat and electricity, so that the biogas G can be utilized more efficiently as an energy source. In particular, the waste heat can be extracted as hot water or steam and used to heat or keep warm the methane fermentation tank 21 as a methane fermentation facility, so that the costs of heating or keeping warm the methane fermentation tank 21 can be reduced.

In the above aerobic fermentation, the explanation has been given on the assumption that aerobic microorganisms are used. However, this does not mean that there is no adhesion of anaerobic microorganisms, but rather that an environment in which aerobic microorganisms can work is created.
In carrying out the present invention, the configuration, ingredients, blending, manufacturing method, etc. of the waste treatment plant and the waste treatment method are not limited to those in the above examples. In addition, the numerical values given in the embodiments and examples of the present invention do not all indicate critical values, and some numerical values indicate suitable values for carrying out the invention, so that even if the numerical values are slightly changed within the allowable values, the implementation of the invention is not denied.

Reference Signs List 1A, 1B Waste 2 Bulk density adjusting material 3 Microorganism-attached material 21 Methane fermentation tank 10A Sorting residue 10B Material to be subjected to methane fermentation treatment 33 Cogeneration facility 100 Material to be subjected to aerobic fermentation treatment 110 Building 120 Aerobic fermentation drying device 130 Air plenum room 140 Biological deodorization device 142 Biofilter 150 Methane fermentation residue 171 First circulating water facility 181 Second circulating water facility 200 Material to be subjected to aerobic fermentation and drying treatment 210 Solid fuel material 220 Compost material Y3 Mixing yard (mixing work area)
G. Biogas

Claims (10)

A pretreatment facility that separates waste into a high-water content methane fermentation target material to be subjected to methane fermentation and a low-water content selection residue other than the high-water content methane fermentation target material, and conditions the methane fermentation target material into a slurry having a solid content of 15 to 30% by mass ;
a methane fermentation facility for producing biogas by methane fermentation of the slurry-like methane fermentation target material;
A mixing operation section that mixes the slurry-like methane fermentation residue after the methane fermentation of the methane fermentation target with the selection residue, and further adds a bulk density adjusting material for forming voids in the deposits to increase the volume and a microbial attachment material having aerobic microorganisms attached thereto, to prepare an aerobic fermentation target to be subjected to aerobic fermentation;
An aerobic fermentation and drying facility for aerobically fermenting and drying the aerobic fermentation treatment product;
a post-treatment facility for separating solid fuel material and/or compost material from the aerobically fermented and dried product obtained after the aerobically fermented and dried product is aerobically fermented and dried. The waste treatment plant according to claim 1 further comprises a first circulating water facility that collects wastewater from the aerobic fermentation and drying facility where the aerobic fermentation material is aerobically fermented, filters the wastewater, and then sprays the aerobic fermentation material that is aerobically fermented in the aerobic fermentation and drying facility. Further, a deodorizing system that biologically deodorizes the air discharged from the aerobic fermentation and drying system in which the aerobic fermentation treatment product is aerobically fermented using a biofilter containing aerobic microorganisms and exhausts the air to the outside;
3. The waste treatment plant according to claim 1, further comprising: a second circulating water facility for sprinkling water on the biofilter of the deodorizing facility, recovering surplus water from the sprinkling, and reusing the surplus water for sprinkling the biofilter. The waste treatment plant according to claim 3 further comprises an air plenum chamber into which air discharged from the aerobic fermentation and drying equipment in which the aerobic fermentation treatment material is aerobically fermented is input, the humidity of the air is reduced, and the air is output to the deodorization equipment. The waste treatment plant according to any one of claims 1 to 4, further comprising a cogeneration facility that uses the biogas as fuel after refining it to supply heat and electricity. A pretreatment process in which waste is separated into a high-water content methane fermentation target product to be subjected to methane fermentation and a low-water content selection residue other than the high-water content methane fermentation target product, and the methane fermentation target product is refined into a slurry having a solid content concentration of 15 to 30% by mass ;
a methane fermentation step of producing biogas by methane fermentation of the slurry-like methane fermentation target material;
A mixing process in which a slurry-like methane fermentation residue after the methane fermentation of the methane fermentation target material is mixed with the selection residue, and a bulk density adjusting material for forming voids in the sediment to increase the volume and a microbial attachment material having aerobic microorganisms attached thereto are added to prepare an aerobic fermentation target material to be subjected to aerobic fermentation;
an aerobic fermentation and drying step of aerobically fermenting the aerobic fermentation treatment product and drying it;
a post-treatment step of separating solid fuel material and/or compost material from the aerobically fermented and dried product obtained after the aerobically fermented and dried product is aerobically fermented and dried. The waste treatment method according to claim 6, characterized in that in the aerobic fermentation drying process, wastewater seeping out from the aerobically fermented material undergoing the aerobic fermentation treatment is collected, filtered, and then sprayed onto the aerobically fermented material. The method further includes a deodorizing step in which the air discharged from the room where the aerobically fermented material is aerobically fermented in the aerobic fermentation and drying step is biologically deodorized by a biofilter containing aerobic microorganisms and then discharged to the outside.
8. The waste treatment method according to claim 6, wherein in the deodorizing step, water is sprayed onto the biofilter, and excess water from the spraying is collected and reused for spraying onto the biofilter. Between the aerobic fermentation drying step and the deodorization step, there is provided an exhaust adjustment step of reducing the relative humidity of the air discharged from the room where the aerobic fermentation treatment material is aerobically fermented,
9. The waste treatment method according to claim 8, wherein in the deodorizing step, the air conditioned in the exhaust gas adjusting step is subjected to the biological deodorization and exhausted to the outside. The waste treatment method according to any one of claims 6 to 9, further comprising a biogas utilization process in which the biogas is purified and then used as fuel to supply heat and electricity.

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