JP2008259972A - Deodorization apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a deodorization apparatus suppressing diffused gas from reaching in the distance by preventing the gas from rising high, reducing malodor components diffused to the outside for deodorizing. <P>SOLUTION: The deodorization apparatus deodorizes a malodor component generated when composting compost raw materials. A deodorizing part including at least aged compost layer 15 is provided in a deodorization apparatus vessel 11, an aeration part 13 introducing gas containing the malodor component into the deodorization apparatus is disposed near the bottom face in the deodorization apparatus vessel 11. The gas containing the malodor component is introduced from the aeration part 13 into the deodorization apparatus vessel 11, and is diffused into the atmosphere passing through the deodorization part while being reduced in temperature. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a deodorizing apparatus, and in particular, provides a deodorizing apparatus for treating odor components generated in fermentation composting of sewage sludge, animal and vegetable residues, and waste wood.

  There are many proposals for using fertilized compost as an effective microorganism group (useful bacteria) as a raw material to produce organic fertilizer.

First, there is Patent Document 1 as an example of a primitive one. A continuous manufacturing process for compost that is fermented based on wood fragments obtained by processing waste materials and mixing them with domestic waste such as animal manure, activated sludge, sludge, sludge, and sugar beet waste has been proposed. .
This is primitive and valuable information, but it is not practical as it is, and many improved technologies are being proposed one after another.

  For example, in Patent Document 2, high-speed composting is performed by contacting ozone-containing gas in a fermentation process in order to shorten the time for complete ripe composting when the content of biological waste such as lipids and fibers increases. It has been shown that it can.

  Further, Patent Document 3 proposes a method for eliminating the off-flavors and odors from organic industrial waste and making the processed compost easily absorbed by plants in composting treatment of organic industrial waste. A compound containing Ca and a compound containing Mg are added to the treated waste at a predetermined weight ratio of 0.1 to 1.5%.

  These prior arts describe the term organic fertilizer, but the purpose is to reduce the volume and volume by treating the waste, and the social needs at that time were also there. It was far from organic fertilizer, but it was completely different in dimension.

  Therefore, the inventors of the present application have developed a technique for composting harmless organic matter and using it as an organic fertilizer, and filed a patent application first, and disclosed a specific practical technique as Patent Document 4.

  That is, after mixing sludge and approximately 1 to 3 cm square wood chips and spraying fermented bacteria mainly consisting of lactobacilli and yeast, the primary fermentation process for approximately 2 weeks, approximately 2 to 3 weeks The processing method of the sludge which performs the fermentation process which consists of the secondary fermentation process of this and a final fermentation process of about one week is disclosed, and the organic fertilizer of a specific component ratio is also shown.

  The inventors of the present application disclose detailed technical matters in Non-Patent Document 1. The composting technique of this paper is the prior application of the inventors of the present application disclosed in Patent Document 4.

  Patent Document 4 and Non-Patent Document 1 disclosed the most excellent sludge composting technology at that time. Currently, many compost plants are operating according to these disclosed techniques.

However, in the method of fermenting composting raw materials such as sludge as described above into organic fertilizers, it cannot be said that sufficient measures are taken against the odorous components that are generated, and the technology that enhances the effect of the deodorizing device Was demanded.
In particular, there has been a demand for a technique for preventing the scattering of odor components from a compost facility, for example, odor may be confirmed even at a location several km away from a fermentation composting facility.
JP 54-75363 A JP 7-126092 A JP-A-10-95687 JP 2000-169270 A "Sludge reduction and recycling by composting using wood chips and humus soil extracted microorganisms" Kokushikan University Institute of Science and Engineering Report No. 15 (2003) pages 34-49 "Small encyclopedia of wood," Wood Science Institute Kiso Association, Kodansha, pp. 37-38, 2001 “Organization of Organic Waste Resource Encyclopedia”, Organic Resources Recycling Promotion Conference, Agricultural Welfare Association, p.187, 1997 "Microbiology for environmental purification" Ryuichi Sudo, Kodansha, p.4, 1992 “Microbiology for environmental purification”, Ryuichi Sudo, Kodansha, p. 7, 1992 "Introduction to Water Treatment Biotechnology" by Ryuichi Sudo and Kohei Inamori, Industrial Water Research Committee, p.94, 1994 “Microbial engineering” Kazuo Nagai, Shigeru Nakamori, Tetsuo Toraya, Hiroaki Horikoshi, Kodansha, p.40, 1996 “Iwanami Biology Encyclopedia” Iwanami Shoten, p.34, 1974

  The problem to be solved is that it is difficult to deodorize odor components generated in the method of fermenting compost sludge into organic fertilizer.

  The deodorizing apparatus of the present invention is a deodorizing apparatus for deodorizing odor components generated when composting raw material is composted, and is provided in the deodorizing apparatus container and the deodorizing apparatus container, and includes at least an aging compost layer. And an aeration part disposed near the bottom surface in the deodorizing device container and guiding the gas containing the odorous component into the deodorizing device, and the gas containing the odorous component from the aeration unit to the deodorizing device container It is guided into the interior and passes through the deodorizing part while being lowered in temperature, and is diffused to the outside air.

  The deodorizing apparatus of the present invention is a deodorizing apparatus that deodorizes odor components generated when composting raw material is composted. A deodorizing unit including at least an aged compost layer is provided in the deodorizing device container, and an aeration unit that introduces a gas containing an odorous component into the deodorizing device in the vicinity of the bottom surface in the deodorizing device container is provided. Is guided from the aeration section into the deodorizing device container, and is dissipated to the outside air through the deodorizing section while the temperature is lowered.

  In the deodorizing apparatus according to the present invention, preferably, the difference between the temperature of the gas that passes through the deodorizing part and is diffused to the outside air and the outside air temperature is within 4 ° C.

  In the deodorizing apparatus of the present invention, the temperature is preferably lowered by 2 ° C. or more when the gas containing the odor component passes through the deodorizing part.

  In the deodorizing apparatus of the present invention, preferably, a wood chip layer is provided in a lower layer of the aging compost layer in the deodorizing unit.

  In the deodorizing apparatus of the present invention, preferably, in the deodorizing part, a bark layer is provided as an upper layer of the aging compost layer.

  In the deodorizing apparatus of the present invention, preferably, a drainage groove is provided on the bottom surface of the deodorization apparatus container, and the aeration part is disposed in the drainage groove.

  In the deodorizing apparatus of the present invention, preferably, the aging compost layer includes aging compost obtained by composting the compost raw material.

  The deodorizing apparatus of the present invention preferably includes a wood chip in which the aging compost layer is mixed with the compost raw material in composting of the compost raw material.

  In the deodorizing apparatus of the present invention, since the temperature of the gas containing the odor component is lowered in the deodorizing apparatus, the emitted gas is difficult to rise high, and is prevented from reaching far, and the temperature of the gas decreases. At this time, the odor component is taken into the deodorization part, decomposed by microorganisms in the aging compost layer, and the odor component released to the outside is reduced, so that deodorization can be realized.

Below, embodiment of the deodorizing apparatus concerning this embodiment is described with reference to drawings.
The deodorizing apparatus according to this embodiment is an apparatus for deodorizing odor components generated when a compost raw material is fermented by microorganisms to be composted.

A composting facility for composting materials in which an odor component that is a processing target of the deodorizing apparatus according to the present embodiment will be described.
FIG. 1 is a schematic configuration diagram of the composting facility.
The processing capacity of this composting facility is, for example, 165 t / day.
This compost facility has, for example, a mixing yard 20, a primary fermenter 30, a secondary fermenter 40, a finishing fermenter (tertiary fermenter) 50, and a sieving and micro-level fermenter 60.

  The mixing yard 20 is provided with an unused chip storage area 21 adjacent thereto, and a return chip storage area 22 in which a return chip returned by circulating the fermentation process is placed in the mixing yard. In the yard 20, the organic fertilizer raw material used for the composting and the wood chips including the return chips are mixed.

The primary fermenter 30 is composed of, for example, eight-room fermenters 31 to 38 across the passage, and the primary fermentation of the mixture of the compost raw material, the wood chip and the microorganism is performed.
For example, the compost material is aerated in the fermenter only in the daytime, and is processed under conditions that do not aerate at night (from 4:30 in the evening to 8 am) and on holidays.

  The secondary fermentation tank 40 is composed of, for example, four-room fermentation tanks 41 to 44 across the passage, and the secondary fermentation is performed in the same manner as the primary fermentation described above.

The finishing fermenter 50 performs a turnover process necessary for the fermentation state up to the secondary fermentation. Thus, macro-level fermentation is performed.
After the secondary fermentation is completed, the sieving and transported to the micro-level fermenter 60.

In the sieving and micro level fermenter 60, the returned chips are sorted out by sieving from the mixture in which the macro level fermentation has been performed, and the fermentation check process is performed as described above for the obtained sieve passage part. Fermented with.
When the fermentation process at the micro level is completed, the product is packed into a product.

  In the composting facility configured as described above, in order to process odor components generated from the primary fermenter 30, the secondary fermenter 40, and the finish fermenter 50, the first deodorizer 10a and the second deodorizer. 10b and a third deodorizing device 10c are provided.

FIG. 2 is a schematic configuration diagram of the deodorizing apparatus 10 according to the present embodiment. Each of the first to third deodorizing apparatuses (10a to 10c) has a configuration similar to that of the deodorizing apparatus 10.
For example, a drainage groove 12 is provided on the bottom surface of the deodorizing device container 11 made of concrete or the like, and an aeration portion 13 is disposed in the drainage groove 12.
The aeration unit 13 is composed of, for example, a pipe having a diameter of about several tens of millimeters formed with an opening, and is connected to the primary fermentation tank 30, the secondary fermentation tank 40, and the finishing fermentation tank 50 through a pump. The gas containing the odor component generated in each fermenter is introduced into the deodorization apparatus with a predetermined intake amount.
Moreover, said drainage groove | channel 12 is formed in the width | variety from which the space | interval of the wall surface of a groove | channel when the aeration part 13 is arrange | positioned, and the aeration part 13 becomes about 10 mm. The drainage groove 12 is configured to drain the water stored at the bottom of the deodorizing device container 11 to the outside of the device.

  In the deodorizing device container 11 described above, the drainage groove 12 and the aeration portion 13 disposed in the drainage groove 12 are covered to form a wood chip layer 14 having a thickness of, for example, about 500 mm, and the upper layer thereof has, for example, about 1200 mm. Aged compost layer 15 is formed, and a bark layer 16 of about 500 mm, for example, is formed thereon. As described above, the deodorizing part is composed of the wood chip layer 14, the aging compost layer 15, and the bark layer 16.

The deodorizing part including the aging compost layer 15 serves as a “filter medium” contributing to deodorization. In the present embodiment, as the aging compost layer 15, the aging compost generated in the composting facility of the compost raw material in which the odor components to be processed by the deodorization apparatus are generated, that is, the fermentation in the finishing fermenter 50 is finished. It is preferable to use what was done.
In composting of the above compost raw material, fermentation aging is performed in a state where wood chips are mixed as described below, and wood chips are also mixed in the aged compost, In the aging compost layer of the deodorizing apparatus of this embodiment, it is preferable to use the wood chips in a mixed state, thereby ensuring air permeability in the aging compost.

The wood chip layer 14 can use the wood chips used in the composting of the above compost raw material as they are, and uses unused wood chips, return chips returned by circulating the fermentation process, a mixture thereof, and the like. be able to. Air permeability can be secured and the gas guided from the aeration section can be guided to the aged compost.
The bark constituting the bark layer 16 is a bark of wood and contains a large amount of lignin, so it is not suitable for the composting process, but here it is a layer provided for the purpose of preventing the aging compost layer 15 from scattering, and is breathable. And the gas that has passed through the aging compost layer 15 can be quickly diffused to the outside air.

Here, in said deodorizing apparatus, the gas containing an odor component is led into the deodorizing apparatus container from the aeration part, and is passed through the deodorizing part while being reduced in temperature while being diffused to the outside air.
For example, the difference between the temperature of the gas that passes through the deodorizing part and is diffused to the outside air and the outside air temperature is within 4 ° C.
Alternatively, for example, the temperature can be lowered by 2 ° C. or more when a gas containing an odor component passes through the deodorization part.

In the prior art, for example, odor was sometimes confirmed even at a location several km away from the fermentation composting facility. This is because the air mass containing the odor component is diffused to the outside air at a high temperature, and the temperature with the outside air A mechanism can be considered in which the air mass rises high due to the difference, cools while moving to a place several kilometers away with the wind, gradually descends, and descends to the ground.
In the deodorization apparatus of this embodiment, since the temperature of the gas containing an odor component is lowered in the deodorization apparatus, the emitted gas is difficult to rise and is prevented from reaching far.
Furthermore, when the gas passes through the deodorization part, the expected temperature is lowered, the odor component is dissolved and taken in the moisture of the deodorization part, decomposed by microorganisms in the aging compost layer, and the odor component released to the outside decreases. Deodorization can be realized.

The first to third fermenters in the above compost facility take in outside air and perform aeration, but the amount of intake air from the first to third fermenters by aeration of the deodorizing device is from the first to the outside air. It is preferable to set more than the amount taken into the tertiary fermenter.
Since the first to third fermenters are not sealed, the odor component may be directly diffused to the outside air. By increasing the amount of intake air taken from the third fermentor to the deodorizer, it is possible to make it difficult for odor components to be directly diffused from the first to third fermenters to the outside air.

  In addition, the “filter floor area” of the deodorization apparatus is designed so that intake air does not become excessive in consideration of the deodorization efficiency and the intake amount taken in from the first to third fermenters. For example, in order for the deodorization efficiency to function sufficiently, the speed (superficial speed) at which the gas containing the odor component passes through the deodorization part that is a filter medium is estimated as 0.8 m / min, and the first to third deodorization apparatuses are estimated. Necessary filter floor area is calculated and set.

Hereinafter, the composting method of the compost raw material which generates the odor component which the deodorizing apparatus which concerns on this embodiment makes the object of deodorizing is demonstrated.
FIG. 3 is a flowchart showing the steps of the composting method for composting material.
Step S10 for mixing the wood chip including the return chip and the organic fertilizer raw material, Step S20 for fermenting the mixture of the organic fertilizer raw material and the wood chip at a macro level, and sieving the mixture to separate it into the return chip and the sieve passage portion. It has process S30, process S40 which judges the progress of fermentation by observing the section of the deposit of a passage part of a sieve, and fermenting and ripening a sieve part by a micro level, and making it an organic fertilizer.

  Preferably, the step S20 for fermenting at the macro level includes a primary fermentation step S21, a secondary fermentation step S22, and a finish fermentation step S23, and the mixture is aerated and turned over to perform fermentation at the macro level. To do.

Preferably, in step S50 of fermenting at a micro level, the contact between the sieve passage and the atmosphere is promoted to promote the growth activity of microorganisms remaining in the sieve passage.
Specifically, in the step of fermenting at the micro level, the sieve is expanded by spreading the sieve passage part on the sheet, and / or by putting the sieve passage part in a container and stirring, the sieve part and the atmosphere are mixed. Promote contact.

In the composting method of the compost raw material described above, as step S40 for determining the progress of fermentation by observing the cross section of the mixture or the deposit passing through the sieve, for example, a white portion is formed inside the mountain. The progress of the fermentation is determined by confirming that it exists.
Or, for example, as a process of confirming the progress of fermentation, a part of the mixture during the final fermentation is extracted and separated into a return chip and a sieve passing part by a sieving process, and a pile of deposits of the obtained sieve passing part is formed. Then, it is possible to determine the progress of fermentation based on the fact that a white portion is formed inside the mountain and the amount of heat generated from the mountain is observed by cutting the mountain and observing the cross section (S24).

In the composting method of the compost raw material, preferably, the fertilizer raw material contains sewage sludge and / or animal and plant residues.
As the main raw material sewage sludge, sludge from a combined treatment tank that is widely installed in large-scale sewage treatment plants and households, that is, sewage sludge derived from humans is used. Sewage sludge derived from the excrement of humans (humans and humans) is currently the best from the viewpoint of safety, security, environmental impact, etc. as a fertilizer raw material, and its nutritional value is high, so as a fertilizer raw material Is optimal. In addition, effective use and recycling of increasing sewage sludge has become a major social issue, and it is a biomass raw material that cannot be overlooked from that viewpoint.

  Do not use sludge derived from animals other than humans unless safety has been confirmed. This is because sewage sludge derived from cattle, pigs, horses, and other animals has a high risk of containing antibiotics, heavy metals, agricultural chemicals, etc. contained in feeds or drugs. On the other hand, human excreta has few harmful substances such as hormones, antibiotics and heavy metals, and is rich in nutritional components and is highly safe overall. It becomes an effective fertilizer that is safe and secure.

  Animal and vegetable residues are also essential raw materials from the viewpoint of organic waste that is to be effectively processed and discharged in large quantities, and nutritional component adjustment. Also in this respect, from the viewpoint of safety, security, and environment, a residue generated in the processing place of what is eaten or drunk by humans is preferable. Specifically, it includes residues associated with food processing such as wastewater treatment sludge and meat in food processing factories such as ham factories, and tea leaf residues of green tea for PET bottles. In other words, it is the residue of what human beings eat and drink, the residue in the process of manufacturing it, and the residue of its raw materials. In the course of the biological cycle, there is a concern that accumulation and concentration will increase even with trace amounts of components, so those that have been administered pesticides, antibiotics, hormones, etc. should be thoroughly eliminated.

  The wood chips (wood chips) used in the composting method of the above compost raw materials are not wood chips cut with a cutter or saw, but are wood chips made by physically crushing with a crusher or the like. It is important that the fine pores (honeycomb tube-like pores described later) are not blocked, and this is the first requirement for wood chips.

The second requirement for wood chips is that the lignin component is as low as possible. For this reason, waste wood such as old wood or pillars accompanying the dismantling of a house, which is more than 5 years after logging, preferably 20 years or more, is optimal. Of course, such timber can be used if lignin is not included or reduced significantly by any means.
Since the size and shape of the wood chip are not essential conditions, they may be appropriately selected from the relationship with the machine to be used and the processing space. As will be described in detail later, the role of the wood chip in the present invention is as follows: (1) where microorganisms reside, (2) ensuring air permeability in the fermentation process, (3) reducing the amount of water contained in the raw material, (4 4) The material of the return tip.

  As the last part of the raw material, the return chip (planted wood chips) will be described. Wood chips containing various types of microorganisms are sieved after the compost fermentation finishing stage, and chips that do not pass through the sieve are returned to the initial raw material mixing section. This is the return chip. A large number of bacteria suitable for compost survive on this return chip, and bacteria suitable for the newly introduced compost material will be seeded. Further, the return chip sequentially passes through the fermentation process in an extruded flow together with the compost material, and bacteria suitable for the fermentation state are activated at each stage. For this reason, not only fermentation starts up smoothly, but also the generation of malodor is reduced during the process.

  Since the above composting method of composting raw material is composting by microbial fermentation, considerations specific to microbial fermentation are important. That is, an excellent fermented product cannot be made until the many microbial environments involved in the fermentation process are stabilized. In other words, as many operations are repeated, the walls and ceilings of processing spaces such as factories and even mechanical devices such as excavator loaders and agitation devices are optimized to ensure a stable microbial environment. Only then has an excellent product been made. It can be thought of in the same way as the effects of microorganisms living in sake breweries in sake brewing. The return chip is a chip that contributes to excellent composting by being repeatedly circulated through many operations.

  Although it is customary to differ for every plant, it is preferable to use the return chip of the plant implemented by the method of the present application for another new plant because time is shortened. However, since different aspects such as temperature, humidity, and indigenous microbial species can be different, it is best to use a return chip made in that plant.

  As is clear from the above description, in the composting method of the compost raw material, no special microorganism is sprayed or administered from the raw material stage. Rather, it is not preferable because there is even a concern that a stable microbial environment suitable for the situation is prepared.

Next, the above process will be described.
Regarding the blending / mixing ratio of raw materials, the mixing step S10, the macro-level fermentation step S20, and the sieving step S30, the contents described in our earlier patent (Patent Document 4) and paper (Non-Patent Document 1) Therefore, detailed description is omitted here.

  In the composting method of the compost raw material described above, the fermentation process at the macro level corresponds to what is described as the fermentation or fermentation process in Patent Document 4 and Non-Patent Document 1. That is, it is a step of fermenting a sludge mixture containing coarse and irregularly shaped wood chips extending to several tens of centimeters. In this embodiment, in order to distinguish from the below-mentioned micro level fermentation process, it describes with this name.

  The macro-level fermentation process S20 requires aeration (fan) and turn-over (stirring, replacing), which is necessary for the gradual fermentation specific to the microbial reaction. In this embodiment, it is preferable to divide into three stages (namely, primary fermentation process S21, secondary fermentation process S22, and finish fermentation process S23).

Here, primary fermentation process S21 is a process aiming at proliferation of fermentation bacteria, elimination of sludge odor, reduction of water content of sludge, and decomposition of relatively large solid matter in sludge.
In the secondary fermentation step S22, the water content is reduced to 40% to 50% in the primary fermentation step S21, and the sludge refined compared to before the fermentation step is further advanced in fermentation to the carbon component in the sludge. This is a step of improving the degree of decomposition and reducing the water content to 35% to 45%.
Finishing fermentation process S23 completes decomposition | disassembly of the carbon component in the sludge by fermentation about the sludge from which moisture content fell to about 35%-45% in secondary fermentation process S22, and the moisture content of sludge is 30%- It is a process aimed at reducing to 40%.

In the sieving step S30, the material is separated into a coarse product that does not pass through the sieve (return chip) and a granular material part that passes through the sieve (fluid passing part). The sieve passage part may contain a powdery substance in addition to the granular part.
Normally, the granular material passing through the sieve accumulates and rises like a mountain. It may be placed directly in the container to facilitate later handling and transport operations. In any case, it has a certain thickness (depth).
Here, in each fermentation process, a part of the wood chip is chipped or collapsed to become a small piece of wood, but by adjusting the size of the eyes of the sieve used in the sieving step S30, The mixing ratio can be adjusted. Increasing the size of the sieve will increase the mixing rate of the pieces of wood, and decreasing the size of the opening will reduce the rate of mixing of the pieces of wood.
When mixed with organic fertilizers, the above-mentioned pieces of wood have a function of helping the plants to grow greatly by assisting the independence of the plants when the roots are stretched for some plants. In addition, as an organic fertilizer for growing green on a golf course, it is preferable that wood chips are excluded.
For this reason, depending on what kind of plant is used, the size of the eyes of the sieve can be changed to change the mixing rate of the pieces of wood.

  In the composting method of the compost raw material described above, the fermentation state is confirmed by exposing the cross section in the thickness direction in the mountain-shaped deposit of the granular material portion (fluid passage portion) formed as described above (S40). . For example, it is a proof that excellent composting has been performed if the mountain-shaped deposit is broken in the depth direction to expose the cross section and the inner layer portion appears white. If the inner layer portion is the same as the surface layer portion and does not look white, a defective product will be made, so it will not be a true organic fertilizer as used herein. This is what we have found as a result of repeated operations. Until this confirmation process was adopted, there was a random variation in the final product, which was unlikely to be a constant product, but this problem was resolved after obtaining this knowledge.

Although the case where the fermentation confirmation process S40 is performed after the sieving process S30 has been described above, it is also preferable to perform the fermentation confirmation process S24 before the sieving process.
That is, a part of the fermented product is extracted from the third stage fermentation process S23 of the macro-level fermentation process S20, sieved and sorted into a return chip and a sieve passage part, and the resulting sieve part is deposited. Form a mountain of objects, cut the mountain, observe the cross-section, and due to the formation of a white part inside the mountain and the amount of heat generated from the mountain, it is not the surface layer of the pile of deposits but the inner layer part After confirming that the fermentation is performed, the whole amount may be transferred after the sieving step.

In the above composting method of compost raw materials, it is presumed that actinomycetes and nitrifying bacteria play a major role in the fermentation process.
Actinomycetes have a fast growth rate, and vigorously grow from the initial stage of fermentation, and white filamentous cells can be visually observed from the inside to the surface of the compost material throughout the entire fermentation process.
On the other hand, nitrifying bacteria having a slow growth rate have never been confirmed so far to confirm that they have sufficiently grown and contributed to fermentation. Nitrifying bacteria are small in number compared to actinomycetes, and it is impossible at the stage where actinomycetes are active. Granules that have passed through the sieve obtained in the sieving process after the role of actinomycetes is almost over (fluid passing part) It is optimal to make a determination in).

In this granule, the number of actinomycetes is reduced, and the nitrifying bacteria having a slow growth rate still have the ability to grow and still exist as main microorganisms. The white state visible in the cross-sectional layer of the granular deposit is the presence of residual nitrifying bacteria, in other words, in the previous fermentation process, not only fast-growing actinomycetes but also slow-growing nitrifying bacteria worked well. I think it is a barometer to show things. It also confirms that the nitrifying bacteria have been firmly picked up on the return tip.
Detailed discussion on the action effect of nitrifying bacteria will be described later.

In the manufacturing method of the organic fertilizer of this embodiment, fermentation process S50 in a micro level is performed after said process.
As described above, since at least nitrifying bacteria having a slow growth rate are still capable of growing in the granules passing through the sieve, the fermentation is not completely completed. It is considered that microorganisms other than nitrifying bacteria still remain. Above all, since the powder or granules passing through the sieve are homogeneous and free of coarse products, microorganisms, fine wood chips, degraded sludge particles, etc. are intimately mixed, so fermentation at the micro level is performed. It is in the environment to be called.

Therefore, this process is important as a final finishing step for producing a fermented product. In the present embodiment, the action of microorganisms in this environment is equivalent to ripening without stopping in the atmosphere, that is, allowing the proliferation activity of nitrifying bacteria to be sufficiently performed.
Specifically, the process is completed in a state where no heat is generated by performing a method such as a method of sometimes stirring in a predetermined container in the atmosphere or a method of depositing on a sheet with a certain thickness. Since fever is a sign that microorganisms are actively proliferating, this process cannot be continued until the fever ceases.
In the step of fermenting at the micro level, it is also possible to adjust the water content by evaporating water in the atmosphere.

  The above composting method of compost raw material provides an organic fertilizer effective for assisting the original ability of a plant that self-grows by skillfully utilizing the soil environment and the atmospheric environment. Ideally, all the constituent elements of the applied fertilizer are absorbed by the growing plant and do not remain in the soil or in the ground water (environmental water). On top of that, delicious crops have yields equal to or better than those using chemical fertilizers. Furthermore, the safe and secure method at the atomic level for both people and the global environment will be the fermentation method, but it is important to take care not to cause species disruption or disturbance in the microbial world.

The deodorizing apparatus according to the present embodiment deodorizes odor components generated in the composting method for compost raw materials.
A deodorizing unit including at least an aging compost layer is provided in the deodorizing device container, and an aeration unit for introducing a gas containing an odorous component into the deodorizing device is disposed in the vicinity of the bottom surface in the deodorizing device container, including the odorous component. The gas is guided from the aeration unit into the deodorization device container, and passes through the deodorization unit while being reduced in temperature while being diffused to the outside air.
Since the temperature of the gas containing the odor component is lowered in the deodorization device, the emitted gas is difficult to rise high and is prevented from reaching far, and when the gas temperature decreases, the odor component is deodorized. Deodorizing can be realized by reducing the odor components that are taken in and decomposed by microorganisms in the aged compost and released to the outside.

  Hereinafter, the knowledge by the present inventors regarding the composting method of the compost raw material will be described.

1. The role of wood chips The structure of wood chips consists of honeycomb tube-shaped pores that are long, and in conifers such as cedar and pine, the temporary conduit is a fibrous cell with a diameter of several tens of micrometers and a length of several centimeters. It is known (see Non-Patent Document 2). Moreover, it has been clarified that the cedar chip has a honeycomb structure and thus is suitable as a microorganism's house and is an excellent carrier in high-temperature aerobic treatment (see Non-Patent Document 3).
Wood chips have fine honeycomb-shaped tubes that are not preyed by large protozoa that cannot enter here, and bacteria that have a slow growth rate using nutrients soaked around the tube as an activity source It is thought that the species can survive. FIG. 4 shows an electron micrograph of a cut surface of a new wood chip.

1.1 The role of wood chips as a microorganism entrepreneur As described above, wood chips are considered suitable as a microorganism entrepreneur. This is thought to be largely related to the size of the microorganisms in the compost sludge.
The large ones of bacteria reach 30 μm, while the small ones are 0.2 μm. Sulfur and iron bacteria are the largest bacteria. For cocci, there are many diameters of 0.5 to 1.0 [mu] m, and for bacilli, (0.5 to 1.0) * (1.0 to 2.0) [mu] m. Actinomycetes are bacteria that have a filamentous form and have been morphologically differentiated like a filamentous fungus. The width of the mycelium is about 0.3 to 1 μm (see Non-Patent Document 4).

The size of the protozoa is about 5 μm at the minimum and some reaches 3 mm at the maximum. In general, most of them are around 50 to 100 μm (see Non-Patent Document 4).
Protozoa are divided into the following four classes (see Non-Patent Document 5).
(1) Flagellates: move with one or more flagella (2) Carnivores: move with pseudopods (3) Spores: have no motility, make spores and are parasitic (4 ) Ciliates: Exercise by cilia

Since the compost deposit is a mass of solid matter, it is expected that protozoa of the carnivorous worms survive in the compost.
Table 1 shows the size and length of protozoan cells generated by sewage treatment.

2. Nitrogen Circulation and Nitrification Bacteria 2.1 Nitrogen Circulation and Nitrification Nitrogen contained in organic substances changes through the following pathways as organic substances are decomposed by microorganisms.

Organic substance (organic nitrogen) → Ammonia → Nitrous acid → Nitric acid → Nitrogen gas
General bacteria Nitrite bacteria Nitric acid bacteria General bacteria

  The above reaction is represented by the chemical formula as follows.

[Chemical 1]
NH ₄ ⁺ + 3 / 2O ₂ → NO ₂ ⁻ + H ₂ O + 2H ⁺
NO ₂ ⁻ + 1 / 2O ₂ → NO ₃ ⁻

  Here, nitrite bacteria (genus Nitorosomonas) are bacteria that change ammonia into nitrite. On the other hand, nitric acid bacteria (genus Nitrobacter) are bacteria that change nitrous acid to nitric acid, and these two genera are collectively called nitrifying bacteria. Furthermore, the reaction (denitrification) in which nitrous acid and nitric acid are converted to nitrogen gas has the ability even in general bacteria, but among the denitrification bacteria, Pseudomomas denitrificans is said to have a high denitrification ability.

The specific growth rate of nitrifying bacteria is 0.21-1.08 day ^{−1 for} the genus Nitorosomonas and 0.28-1.44 day ⁻¹ for the genus Nitrobacter.
It is extremely small compared to 40-60 day ^-1 such as facultative anaerobes such as Escherichia coli and Proteus sp. (See Non-Patent Document 6). This indicates that the growth rate of nitrifying bacteria is extremely slow.
FIG. 5 shows an electron micrograph of bacteria attached to the return chip.

2.2 Wood chips and nitrifying bacteria Since nitrifying bacteria have a slow growth rate as described above, the nitrifying bacteria that were present in the imported material grow somewhat during compost fermentation, but the materials being fermented are extruded. Since it flows in a flow pattern, it will be discharged out of the system together with the finished product. For this reason, in the compost of the system in which the material to be carried is not seeded, the ammonia generated by the decomposition of organic nitrogen is diffused into the atmosphere with almost no nitrification.
In this composting method, chips that are physically crushed are used, not wood chips that have been cut with a cutter over 20 years after logging. As a result, as shown in FIG. 4, the opening of the honeycomb tube of the chip is not crushed, and bacteria can easily enter the tube. Bacteria that have entered the tube are not preyed because the protozoan body that eats them is large and cannot enter the tube. Considering this, nitrifying bacteria with a low specific growth rate (low growth rate) grow in the tube using ammonia that has soaked into the honeycomb tube as a growth substrate and actively oxidize ammonia to nitric acid. Can be considered.
FIG. 6 shows an electron micrograph of bacteria in the obtained organic fertilizer (finished product). This is the deposit after sieving.

3. Oxidizing organic substances in the circulation and sulfur bacteria 3.1 circulation sulfide sulfur of sulfur, particularly sulfur contained in the protein and fat, with the the decomposition of organic matter by microorganisms, S ^2-(sulfite, H ₂ S, etc.). This S ²⁻ changes to sulfate SO ₄ ²⁻ via SO ₃ ²⁻ by aerobic bacteria. When this change is expressed by a chemical formula, the following formula is obtained (see Non-Patent Document 7). In this reaction, sulfite (H ₂ S or the like) is changed to sulfate ion. In this reaction, hydrogen sulfide H ₂ S, mercaptan R-SH, and the like are changed to sulfuric acid, and the generation of malodor is reduced.

[Chemical 2]
S ²⁻ + 2O ₂ → SO ₄ ²⁻

3.2 Chips and sulfur bacteria Sulfur oxidizing bacteria include Thiobacillus, Thiomicrospira, Sulfolobus, and Thiotrix. Data on the specific growth rate of these bacteria has not been published. These bacteria are also estimated to have a slow growth rate. Thiotrix is a large filament, which forms sulfur particles in the cells due to the presence of hydrogen sulfide and acts as an energy source when there is no food supplement. The reaction at that time is probably the following formula (see Non-Patent Document 8). As described above, sulfur bacteria are large and are estimated to be about 30 μm.

[Chemical 3]
H ₂ S + 1 / 2O ₂ → H ₂ O + S
S + 3 / 2O ₂ + H ₂ O → H ₂ SO ₄

  It is presumed that sulfur bacteria also enter the honeycomb tube of the chip, are not preyed by protozoa, and change sulfides to sulfuric acid.

4). The effect of wood chips Wood chips with various types of microorganisms are put into a sieve after fermentation in the compost finishing stage, and chips that do not pass through the sieve are returned to the first mixing tank (return chips) and newly added. Mixed with the compost material carried in. A large number of bacteria suitable for compost survive on the return chip, and bacteria suitable for the newly introduced compost material will be seeded. Further, the return chip moves along with the compost material in the form of an extruded flow in the fermenter, and bacteria suitable for the fermentation state are activated at each stage. For this reason, not only fermentation starts up smoothly, but also the generation of malodor is reduced during the process.

  In addition, the wood chips can be stacked in a pyramid shape, and sludge enters the gaps between the chips, so that the sludge is not compacted and air permeability is improved. Further, it is considered that the chip has honeycomb-shaped pores, and air is released from the holes, improving air permeability. In addition, it helps to reduce the moisture content of the imported material.

Based on the above considerations, it seems that the important role and effect of the fermentation growth confirmation process described above will be highlighted.
In other words, it was a very coarse mixture of wood chips and sludge until the fermentation process, but in the sieving process, it became a “powdered or granular material” and a coarse product (the portion that did not pass through the sieve). To be separated. This “powder or granule” is made up of three main components: micro-sized microorganisms, fermentation objects (composts), and finely crushed wood chips. Since the various microorganisms involved in fermentation and their food (fermentation object) are rearranged in close proximity, it is thought that “fermentation at a microscopic level” will proceed again. At that time, nitrifying bacteria and sulfur bacteria having a slow growth rate are considered to be relatively active. In addition, it is considered that the growth of nitrifying bacteria and the like is not observed in the surface layer portion of the powdery or granular pile passing through the sieve because ammonia and the like easily escape into the atmosphere.

From the above consideration, it can be understood that the fermentation process at the micro level is important in the above-mentioned composting method of compost raw materials.
After the sieving process, it can be said to be an essential process for performing “fermentation in a micro dimension”. In macro-level fermentation, micro-sized bacteria and protozoa are actively working on a mixture of coarse and irregularly shaped wood chips and wet sludge. This is because, from the viewpoint of microorganisms, the presence of wood chips that are huge in size is a distance obstacle to movement, and is considered to be an obstacle to the completion of homogeneous fermentation as a whole. It is necessary to remove this distance obstacle, achieve a homogeneous fermentation state, and use up the remaining growth potential of the microorganisms. It is understood that fermentation at the micro level is important in producing excellent fermented products.

Example As an organic fertilizer raw material, 9 tons of sewage sludge (dehydrated) generated at a sewage treatment plant in Tochigi Prefecture and 1 ton of dehydrated sludge generated at a wastewater treatment facility of a food processing plant, 1 The wood chip and the return chip, which are about 5 times larger, were mixed with a shovel loader. This mixing process was carried out in a large concrete container (width 5 m, depth 5 m, height 2 m, no ceiling, building with roof with exit open).

  The wood chip used here is obtained by cutting old wood that has been discarded from house demolition into a size of several centimeters to several tens of centimeters using a crusher. The return chip is a coarse product (wood is a main component) that has not passed through the sieving step in the processing step of the plant operated by the method of the present invention. As for the ratio of the return chip to the wood chip, 80% was the return chip and the remaining 20% was the wood chip.

  The macro-level fermentation process was performed in three stages for convenience. The space is the same size as the mixing step, but is configured to be aerated from a large number on the concrete floor.

First, in the primary fermenter, the mixture was piled up in a mountain shape for 2 weeks as a primary fermentation step. During this time, aeration (air blowing) was performed every day for 7 hours. Stirring with the shovel loader and pile-up work were performed only once on the 7th day.
In the final stage of the primary fermentation, the temperature of the fermented processed product piled up in a mountain shape was 68 ° C., the pH was 7, and the water content was 55%.
On the 14th day, which is the final day of the primary fermentation, the entire fermented product was transferred to a secondary fermentor with a shovel loader and stacked in a mountain shape.

The structure and size of the secondary fermentor were the same as the primary fermentor. Here, the treatment for 3 weeks was performed as a secondary fermentation process. As a general rule, aeration (air blowing) was carried out every day for 7 hours in the daytime, and turning-over and re-loading with an excavator loader were performed twice on the 7th and 14th days.
In the final stage of the secondary fermentation, the temperature of the fermented product was 74.3 ° C. inside the sediment and 23.5 ° C. on the surface. Moreover, PH was 7.5 and the water content was 40%.
On the 21st day, which is the final day of the second fermentation, the entire fermented product was transferred to a third fermenter where final fermentation was performed with a shovel loader.

  The third fermenter is almost the same as the first fermenter in both container and structure size, but is equipped with a self-propelled automatic turning device. The turn-over was performed while aeration for 7 hours in the day of the week. Stopped at night.

The amount of intake air taken into for aeration from the atmosphere to the fermentor above, 56m 3 ^/ min primary fermentation tank, 26.4m 3 ^/ min second fermenter, tertiary fermenter with 9. 1 m ³ / min. Since the intake air amount from each fermenter to the deodorizing device is larger than the intake air amount to each fermenter, the intake air amount from the primary fermenter is 60 m ³ / min, and the intake air amount from the secondary fermenter is 30 m. ³ / min, the amount of intake air from the third fermenter was 10 m ³ / min.
Here, as shown in FIG. 1, the first deodorizing apparatus 10a is connected to the primary fermenter and the intake air amount is 20 m ³ / min. Are connected to the primary fermentor and the secondary fermentor, the intake air amount from the primary fermentor is 40 m ³ / min, the intake air amount from the secondary fermentor is 30 m ³ / min, 70 m ³ in total. / Min. As a result, a total of 60 m ³ / min is drawn into the deodorizer from the primary fermentor, and 30 m ³ / min is drawn from the secondary fermenter.
The 3rd deodorizing apparatus 10c was connected to the 3rd fermenter, and the intake air amount was 10 m < ³ > / min.

If the superficial velocity is set at 0.8 m / min, the filter bed area required for the first deodorizer that sucks air at 20 m ³ / min is 25 m ² , and the filter bed area required for the second deodorizer that sucks air at 70 m ³ / min is The filter floor area required for the first deodorizer that sucks air at 87.5 m ² and 10 m ³ / min is calculated as 12.5 m ² . Actually, the filter bed area of the first deodorizer is 30 m ² , the filter bed area of the second deodorizer is 90 m ^2, and there is room in the site for the third deodorizer, so it is possible to inhale at 30 m ³ / min. It was 37.5 m ² .

As described above, the deodorization was performed in the first to third deodorizers for treating the odor components generated in the fermentation processes in the first to third fermenters in the compost facility and in each fermentation process.
In the first deodorizing apparatus 10a, the temperature t ₂ of the gas sucked into the deodorizing apparatus, the temperature t _{3 of} the gas diffused from the first deodorizing apparatus, and the outside air temperature t ₁ are changed in various weather conditions. Measured below.
The results are shown in Table 2 below.

The temperature of the gas containing the odor component sucked into the deodorizing device was lowered when passing through the deodorizing device.
The temperature of the gas diffused from the first deodorizing device is within 4 ° C with respect to the outside air temperature, that is, t ₃ -t ₁ is 4 ° C or less, or the odor component sucked into the deodorizing device When the gas containing gas passes through the deodorizer, the temperature is lowered by 2 ° C. or more, that is, t ₂ -t ₃ is 2 ° C. or more.

  Moreover, in the measurement of the odor component using the detector tube manufactured by Gastec, ammonia is about 2.0 to 2.5 ppm and amine is about 7.0 ppm in the vicinity of the fermentation deposits of the first to third fermenters. However, in the gas emitted from each deodorizing device, the concentrations of ammonia and amine were lowered and were below the detection limit of the detector tube (ammonia was 1.0 ppm, amine was 5.0 ppm).

The present invention is not limited to the above description.
For example, the aged compost used in the deodorizing apparatus is not limited to that obtained from the composting facility to be deodorized, but may be used from other facilities. Wood chips are not necessarily mixed in the aging compost.
In the above embodiment of the present invention, the wood chip layer and the bark layer constituting the deodorizing part may be replaced with other materials having the same function.
In addition, various modifications can be made without departing from the scope of the present invention.

  The deodorizing apparatus of the present invention can be applied to an apparatus for deodorizing odor components generated in a composting method for compost raw materials.

FIG. 1 is a schematic configuration diagram of a composting facility that implements a composting method for composting raw materials that generates odor components to be processed by a deodorizing apparatus according to an embodiment of the present invention. FIG. 2 is a schematic configuration diagram of a deodorizing apparatus according to an embodiment of the present invention. FIG. 3 is a flowchart showing the steps of a composting method for composting raw materials for generating odor components to be processed by the deodorizing apparatus according to the embodiment of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10, 10a, 10b, 10c ... Deodorizing device 11 ... Deodorizing device container 12 ... Drainage channel 13 ... Aeration pipe 14 ... Wood chip layer 15 ... Aging compost layer 16 ... Bark layer 20 ... Mixing yard 21 ... Unused chip storage place 22 ... Circulation Chip storage area 30 ... primary fermenter 31-38 ... fermenter 40 ... secondary fermenter 41-44 ... fermenter 50 ... finishing fermenter 60 ... sieving and micro level fermenter

Claims (8)

A deodorizing device for deodorizing odor components generated when composting raw material is composted,
A deodorization device container;
A deodorizing part provided in the deodorizing device container and including at least an aging compost layer;
An aeration unit disposed near the bottom surface in the deodorizing device container and guiding the gas containing the odorous component into the deodorizing device,
A gas containing the odor component is guided from the aeration unit into the deodorization device container and is diffused to the outside air through the deodorization unit while the temperature is lowered. The deodorizing apparatus according to claim 1, wherein a difference between a temperature of a gas that passes through the deodorizing unit and is diffused to the outside air and an outside air temperature is within 4 ° C. The deodorization apparatus according to claim 1, wherein the temperature of the gas containing the odor component can be lowered by 2 ° C. or more when passing through the deodorization unit. The deodorization apparatus according to claim 1, wherein a wood chip layer is provided in a lower layer of the aging compost layer in the deodorization unit. The deodorization apparatus according to claim 1, wherein a bark layer is provided on the aging compost layer in the deodorization unit. A drainage groove is provided on the bottom surface of the deodorizing device container,
The deodorization apparatus according to claim 1, wherein the aeration unit is disposed in the drainage groove. The deodorization apparatus according to claim 1, wherein the aging compost layer includes aging compost obtained in composting of the compost raw material. The deodorizing apparatus according to claim 1, wherein the aging compost layer includes wood chips mixed with the compost raw material in composting of the compost raw material.

Images