JP2005041738A - Composting processing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for processing a composting treatment that effectively utilizes wooden chips manufactured from scrap wood as a secondary material or a material such as vegetable debris and the like as a compost raw material in the composting treatment processing. <P>SOLUTION: In carrying out the composting treatment to proceed full maturity composting, the primary fermentation and the secondary fermentation of livestock excrements, and animal and plant debris combined at a predetermined mixing ratio are continuously performed using the secondary material containing wooden chips manufactured by processing a thinning material, a pruned tree, wooden building scraps into the size of 8-12 mm in diameter or side and 10-50 mm in length. At the end of the primary fermentation and the secondary fermentation, the wooden chips are separated from the compost by sieving the compost. It is also possible that the wooden chips removed from the compost by the sieving is dried and recycled as a recycled secondary material. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a composting method, and in particular, from the viewpoint of recycling organic resources, composting that makes it possible to effectively use wooden chips manufactured from waste materials as secondary materials and materials such as vegetable residues as compost raw materials. It relates to the processing method.

  Various developments and improvements have been made to facilities, devices, and composting methods for "composting" processing technology that uses livestock excreta such as livestock manure.

  Materials used in the composting process include compost raw materials and auxiliary materials. The composting material is livestock excrement such as cow dung, pork dung, chicken dung, etc., and the auxiliary material is mixed with the livestock excrement to increase the porosity and improve the air permeability. There is compost.

  Moreover, the composting process is generally a combination of a primary process in a primary fermenter and a secondary process (secondary fermentation) as the next process. Primary treatment is an aerobic microbial activity for the purpose of decomposing readily degradable organic matter that causes growth failure when compost material is applied to crops, and the treatment period is expected to be about 15-25 days. It is. Further, the compost is stabilized by further ripening in the secondary treatment (see Patent Document 1).

  By the way, the appropriate environmental conditions to activate the activity of aerobic microorganisms are (1) nutrient sources, (2) moisture, (3) air, (4) microorganisms, (5) temperature, and (6) composting period. It is important to proceed with primary fermentation under conditions where these are well balanced (see Non-Patent Document 1). Of these conditions, adjusting the moisture (about 65% as the original compost) is an improvement in air permeability and at the same time adjusting the specific gravity (specific gravity). It has been found that the temperature rise during the composting process is faster when the specific gravity is smaller even at the same moisture ratio. In terms of temperature, keeping the initial fermentation temperature at 60 ° C. or more for 2 days or more is required to eradicate various germs and harmful microorganisms. For example, rice bran is used in many composting plants as a moisture regulator and as a secondary material effective in securing the gas phase.

JP 2000-7475 A Central Livestock Society, “Composting Facility Design Manual”, 3rd edition, Central Livestock Society, March 2003, p.1

  However, when viewed from the supply side, Japanese rice buds are difficult to obtain in areas such as mountainous areas and fields, because the collection period is only once a year once a year. Even in such a case, since the collection time is only once a year, a storage place that can store the total amount of use for one year is required. In addition, when piled up, there are problems such as spontaneous ignition, and storage needs attention. As other auxiliary materials, woody materials such as sawdust, bark (bark) and chips generated during wood processing are used from the viewpoint of recycling. Sawdust is used as an auxiliary material along with the rice bran. However, when fine, the formation of the gas phase is not sufficiently achieved, and there is a problem that the air permeability cannot be sufficiently improved. Furthermore, in general, the presence of substance components that inhibit the growth of crops in woody materials has been pointed out, and their full use has not been achieved. Among them, a wood chip which is a dry material processed into a fine fiber shape or a thin rod shape by a crusher such as a chipper can form a sufficient gas phase by being dispersed in a compost raw material. For this reason, if it mixes well in a composting process process and can improve the permeability of compost and can be removed before it becomes fully matured compost, it becomes an effective auxiliary material.

  Further, as described above, livestock excrement has been used as a compost raw material, but there is also a demand for recycling uncooked residues such as raw garbage and food residues for composting in the suburbs of cities. Livestock excreta contains a large amount of nitrogen, so it has a low C / N (carbon ratio) and good degradability, while it is used as a fibrous material for uncooked residues including vegetables such as crop harvest residues and garbage. Plant residue has a high C / N ratio, promotes microbial nitrogenization, and may lead to nitrogen starvation. For this reason, when using the residue which consists of fibrous materials for a compost raw material, sufficient care was required. Moreover, the treatment of animal uncooked residues of meat and seafood discharged as garbage from ordinary households also has the same problem.

  Therefore, the object of the present invention is to solve the above-mentioned problems of the prior art, effectively use wood chips in the composting process, and various animal and plant residues discharged as raw garbage as compost raw materials. It is to provide an effective composting method from the viewpoint of recycling organic resources.

  In order to achieve the above object, the present invention continuously performs primary fermentation and secondary fermentation using livestock excrement and animal and vegetable residues mixed at a predetermined mixing ratio using auxiliary materials including wood chips, and complete ripe compost. A composting method for promoting composting, characterized in that, at the end of the primary fermentation or secondary fermentation, compost is sieved to remove the wood chips from the compost.

  The wood chip is preferably processed from thinned wood, pruned tree, and wooden building waste, and specifically, processed into a diameter or a side of 8 to 12 mm and a length of 10 to 50 mm.

  It is preferable from the viewpoint of material recycling that the wooden chips removed from the compost by sieving are dried and reused as recycled secondary materials.

  In the above composting method, the livestock excrement and the animal and vegetable residue are mixed at a livestock excrement weight of 1.3 or less with respect to the animal and plant residue weight, and the moisture content is 58 to 62% with the auxiliary material including the wood chip. It is preferable to adjust to.

  In addition, the primary fermentation is continuously performed for 18 to 20 days, and the secondary fermentation is continuously performed for 18 to 22 days. The primary fermentation is matched with the fermentation rate of the aerobic microorganism, and the initial fermentation is once / day. In the middle period, it is preferable to stir compost at a rate of once every 2 days.

  As a specific number of days, the initial stage of fermentation is preferably from the first day to the seventh day, and the middle stage of fermentation is preferably from the eighth day to the 20th day.

  As mentioned above, organic resources recycling is efficient by mixing livestock excrement and vegetables, meat residues, etc. as compost materials in an appropriate ratio, and processing wood as waste material into secondary materials. It can be realized well and can promote a resource recycling society.

Hereinafter, an embodiment of the composting method of the present invention will be described.
[Material formulation]
(Compost raw material)
In the present invention, the ratio of the weight of uncooked residues (hereinafter referred to as animal and plant residues) including crop harvest residues, vegetables such as garbage, meat, seafood and the like to the weight of livestock excrement as the compost raw material is 1. 3 or less was used as a compost raw material. Here, livestock excrement is a general term for manure excreted from livestock, and may be cow dung, pork dung, chicken dung, etc. In addition, animal and vegetable residues include the above-mentioned crop harvest residues discarded at harvest, vegetable grounds generated during cooking, meat, seafood uncooked residues, food residues, etc., fiber materials such as vegetables and meat, It shall be a generic term for residues containing a large amount of fish and shellfish proteins and lipids. When the weight ratio exceeds 1.3, the effective components (nitrogen, phosphoric acid, potassium) of the finished compost become low (each tends to be lower than the standard value of 1%). In addition, since the residue varies greatly depending on the type, the higher the weight ratio, the worse the quality of compost.

(Combination of secondary materials)
The composition of the auxiliary material is determined according to the result of moisture measurement of the compost raw material to be used, but when using compost material containing rice straw from the beginning, such as cow dung, for example, its weight. It is preferable to internally convert. It is preferable that vegetable residues and the like used as compost raw materials are passed through a squeezing machine or the like in advance to adjust the water content and then measure the water content to determine the auxiliary material composition. In addition, since vegetable fermentation etc. may interfere with fermentation promotion when forced dehydration or drying is performed, it is preferable to use the vegetable residue etc. in the pressing state of a draining grade. In addition, it is preferable to adjust the moisture content of the compost material at the time of an auxiliary material mixing | blending to 58 to 62%.

[Use of wood chips]
In the present invention, a wood chip is used as an auxiliary material and is collected and removed at the end of the fermentation process of either primary fermentation or secondary fermentation as described later.
(Chip material)
As a raw material of the wood chip, any of those obtained by converting pruned trees such as thinned wood and roadside trees into chips, and those obtained by converting waste materials generated at the time of demolition of wooden buildings into chips can be used. In the case of a chip manufactured from a pruned tree, it is preferable that the chip is dried by being left in the air after the chip is processed so that the chip is sufficiently dried.
(Wood chip dimensions)
A wood chip is a thin bar material chipped by a known chipper device, and there is variation in the crushed state, but the thickness (diameter or one side) in the fiber direction of the wood is about 8 to 12 mm, and the length is 10 to 10 mm. It is a thin bar shape cut to 50 mm. Regardless of the material, a material in a sufficiently dry state is used, and the compost after the secondary fermentation is sieved with a 10 mm sieve as will be described later to recover the unfermented wood chips. The C / N ratio of the fully matured compost obtained in this way is set to around 20, and a good and safe compost can be obtained. In addition, the wood chips remaining on the sieve can be recycled as a secondary material in a dry state, and carbonized and ashed using a known carbonization device. The carbonized material is used as a deodorizer in the deodorization tank. It is possible to use soil improver etc. by mixing with

[Composting process]
Prior to composting, a mixing tank is provided, and livestock excrement, vegetable residues, etc. as compost raw materials and wood chips as auxiliary materials are added to the mixing tank in a predetermined composition, and the stirring mechanism provided in the tank is sufficient. Agitation is performed so that the wood chips are sufficiently dispersed in the compost raw material, and the compost raw material is transferred to a fermenter in which the composting process of the next step is performed. The composting process is performed by a processing process including a primary process (primary fermentation) and a secondary process (secondary fermentation). In the composting treatment of the present invention, primary treatment with aerobic microorganisms (primary fermentation) is continuously performed in the primary fermentor, and secondary treatment (secondary fermentation) by post-ripening fermentation is continuously performed in the secondary fermentor. It passes through the primary fermentor in 18 to 20 days, then completes the secondary fermentation in 18 to 22 days, and completes the ripe composting in about 40 days in total. As a more detailed treatment process, the primary fermentation matches the fermentation rate of the aerobic microorganism, the initial stage of fermentation (from the first day to the seventh day) is stirred once / day, and the middle stage of fermentation (from the eighth day to the 20th day). = The final stage of primary fermentation) is stirred once every two days. Thereby, the fall of the fermentation temperature by stirring can be minimized. In accordance with each treatment (fermentation) stage, temperature, humidity (water content), pH, etc. are automatically measured, and hydration and ventilation are controlled based on the measurement results.

  In the secondary fermentation, for example, a plurality of secondary fermenters having a container structure corresponding to the amount to be processed per day are prepared, and compost at the completion of the primary fermentation is accommodated in each container every day. The container is placed in a light-shielded state at a predetermined humidity, promotes post-ripening fermentation, and sifts the container at the end of fermentation while performing a predetermined number of compost reversals as the secondary fermentation progresses (days) It is preferable to transfer sequentially to the device position.

  In the final stage of either of the above primary fermentation and secondary fermentation processes, the 10mm sieve residue is returned to compost by sieving the compost with the sieving device provided at the compost discharge point from the fermenter. Remove wood chips completely. At this stage, the amount of compost is set to about 10% by weight of the amount of material input, and a complete ripe compost is achieved. Further, the wood chips removed by sieving can be removed by a known drying apparatus and reused as a recycled material as a secondary material.

  The finally composted material is handled as a bulk, and is packed with a known bagging device or formed into a pellet to produce a product. On the other hand, it is also preferable to produce a soil improving material or the like by blending compost and ash obtained by a carbonization apparatus.

As an example for confirming the effect of the above embodiment, the following experiment method and experiment conducted by blending will be described.
[Determination of sub-material mix ratio]
(Purpose) To confirm the effectiveness of proper mixing ranges such as vegetable residues as part of compost materials and wood chips as secondary materials.
(experimental method)
Initial adjusted moisture content (compost material + secondary material): 60%
Wood chip: processed building waste (φ10mm, length 50mm)
Composting period: 20 days of primary fermentation (1 stir / day → 1 stir / 2 days)
Secondary fermentation 20 days (1 stir / day)
Fermenter: φ1500 corrugated pipe container (composted with compost material)
Table 1 is a list of experimental formulations in this example. In the same table, wood chips and rice straw are used except for the amount of rice straw contained in cow dung as a secondary material. As a breakdown of the wood chips, the above-mentioned recycled material is used at a ratio of new material: recycled material = 1: 2 (weight ratio).

  Tables 2 and 3 show component tables and property tables obtained as a result of analyzing the compost obtained through the composting period.

(Experimental result)
FIG. 1 is a graph showing changes in temperature, water content, specific gravity, and pH during the composting process under the above conditions. As is apparent from the analysis results of FIG. 1 and Tables 2 and 3, compost having reached a sufficient degree of ripening (completely composted) could be obtained through the composting period described above. In this fully matured compost, the C / N ratio can be lowered sufficiently under appropriate changes in temperature (70 → 45 ° C) and water content (62 → 41.7%), and fertilizer components, pH, and germination index It was confirmed that the compost showed good results.

Change graph of compost properties during composting process (experiment).

Claims (7)

  A composting method that continuously performs primary fermentation and secondary fermentation using sub-materials including wood chips, with livestock excrement and animal and vegetable residues mixed at a predetermined mixing ratio, to promote complete ripe composting, A composting method comprising sieving compost and removing the wood chips from the compost at the final stage of the primary fermentation or the secondary fermentation.   The composting method according to claim 1, wherein the wooden chip is manufactured by processing thinned wood, pruned trees, and wooden building waste.   The composting method according to claim 2, wherein the wood chip is processed to have a diameter or side of 8 to 12 mm and a length of 10 to 50 mm.   The composting method according to claim 1, wherein the wood chips removed from the compost by sieving are dried and reused as recycled secondary materials.   The livestock excrement and the animal and vegetable residue are mixed with the animal excrement weight in an amount of 1.3 or less with respect to the animal and plant residue weight, and the water content is adjusted to 58 to 62% with the auxiliary material including the wood chip. The composting method according to claim 1.   The primary fermentation is continuously performed for 18 to 20 days, and the secondary fermentation is continuously performed for 18 to 22 days. The primary fermentation is adjusted to the fermentation rate of the aerobic microorganisms. The composting method according to claim 1, wherein the compost is stirred at a rate of once every two days.   The composting method according to claim 6, wherein the initial stage of fermentation is from the first day to the seventh day, and the middle stage of fermentation is from the eighth day to the 20th day.

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