JP2003160390A - Method for composting woody material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for converting woody materials such as trimmed root chips into a fully ripened compost in a short period of time. <P>SOLUTION: This method for composting woody materials comprises adding high temperature bacteria and cellulose-decomposing bacteria and/or lignin- decomposing bacteria to a ridge with piled woody materials. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for composting woody materials such as root cuts, bark and branches and leaves. More specifically, it uses microorganisms to make woody materials such as rooted chips into fully matured compost in a short period of time. Regarding the method.

[0002]

2. Description of the Related Art Conventionally, wood-based wastes such as debris, bark, and branches are everywhere, from the cutting business associated with large-scale construction such as road construction and dam construction to pruning work such as street trees. Has been discharged. These wood-based wastes are used as livestock materials or raw materials for wood-based compost after incineration, landfill, or crushing. The incineration of these wood materials has environmental problems due to the generation of carbon dioxide and dioxins, and the landfill disposal of wood materials makes it difficult to secure the final disposal site and the land for disposal sites. Have a problem.

In recent years, with the formation of a recycling society, wood materials have also been actively recycled for composting. Compost has been used for a long time to promote the growth of plants such as agricultural crops and to control diseases.
Woody materials are often used as the carbon source for this compost.

[0004]

However, when fertilizing unsaturated compost of woody material as described above to soil, it causes toxic substances such as ammonia due to anaerobic fermentation of woody material and nitrogen starvation of soil, and It will endanger the plants.

Conventionally, when composting a woody material, it is necessary to deposit it for a long time of several years due to the constituent components of the wood, and it is very difficult to compost a felled tree compared with bark and branches. Has been done. It is considered that the composting of wood materials is a phenomenon in which the main constituent components of wood materials, such as cellulose, hemicellulose, and lignin, are decomposed by microorganisms such as bacteria, actinomycetes, and fungi.

Normally, in the composting of wood materials, natural fermentation by natural deposition is common, and microorganisms also depend on contamination from the natural environment. Generally, the fermentation process of wood can be divided into three stages (sugar decomposition period, cellulose decomposition period, lignin decomposition period), and the rate-determining step is the lignin decomposition period. The decomposition of lignin is mainly performed by white rot fungi and brown rot fungi belonging to a group of fungi, but in the early stage of the fermentation process, most of the rotten fungi die off at the early stage of composting because it changes to a fairly high temperature due to exothermic fermentation. As a result, it takes years to decompose lignin. As described above, since it takes a considerable amount of time to make a wooden material into a fully-ripened compost, a rapid and efficient composting method has been demanded.

Therefore, it is an object of the present invention to provide a method for converting a woody material such as felled root chips into a fully-ripened compost in a short period of time.

[0008]

The above object can be achieved by the present invention described below. That is, the present invention provides a method for composting a wood material, which comprises adding a thermophilic bacterium and a cellulose-decomposing bacterium and / or a lignin-decomposing bacterium to a ridge having a wood-based material deposited thereon.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in more detail with reference to the following preferred embodiments. In the present invention, when composting a wood material, the wood material is deposited on a ridge, and a thermophilic bacterium and a cellulolytic bacterium and / or a lignin degrading bacterium are added to the deposit to perform composting in a short time. Is characterized by.

Conventionally, a period of several years is required until the woody material is made into a fully-ripened compost, but as in the method of the present invention, thermophilic bacteria and cellulolytic and / or lignin degrading bacteria are used. As a result, the hardly decomposable cellulose, hemicellulose, and lignin can be effectively decomposed, so that the composting time can be greatly shortened, for example, to about 3 to 6 months.

Further, the temperature of the ridges is relatively high during the sugar-decomposing period and the cellulose-decomposing period of the composting process, and the temperature increase during this period is very important for killing the pathogenic bacteria and weed seeds. Therefore, it is also possible to inoculate the ridge with a thermophilic bacterium and maintain the ridge temperature at a high temperature (70-80 ° C)
It is of great significance in producing high-quality compost, as in the case of inoculating cellulose-decomposing bacteria or lignin-decomposing bacteria later.

In the present invention, as the woody material, felled wood, bark, trunks, branches and leaves, construction waste materials, etc. can be used, and if possible, it is desirable to use them by crushing them into chips. The crushed size may be several inches, but preferably 0.1 to 5 inc for the growth of microorganisms.
A crush size chip of about h is good. Wood chips such as sawdust can also be used.

In the present invention, it is particularly preferable to use an appropriate amount of mushroom waste bed in consideration of the balance of carbon source and nitrogen source. The crushed chips of wood material and an appropriate amount of mushroom waste bacterial bed are mixed well, and the water content is adjusted to about 50 to 60% by weight, and ridge construction is performed.

Next, various useful bacteria are inoculated. First, the method for culturing the bacterium to be inoculated can be the same as that for culturing a normal bacterium, and either a liquid culture method or a solid culture method may be used. As a medium to be used, usually, a medium suitable for growing bacteria or fungi can be used.

It is also possible to directly inoculate the fermented ridges to be composted with the culture that has been liquid-cultured or solid-cultured. However, a small amount of crushed chips of about 1 to 10% by weight of the ridges to be composted is used as a fungus. It is also possible to inoculate and preculture. Although it is the time of inoculation of each useful bacterium, the thermophilic bacterium is inoculated at the time of ridge building or at the early stage of fermentation immediately after ridge building. It is preferable to inoculate the cellulolytic bacterium after the middle stage of the exothermic fermentation, specifically, when the peak of the maximum temperature of the ridges has passed.

The lignin-degrading bacterium has a ridge temperature of 50 to 60.
Inoculate when the temperature drops to ℃. It is also possible to simultaneously add the cellulolytic bacterium and the lignin degrading bacterium. Furthermore, it is not always necessary to use all thermophilic bacteria, cellulose-decomposing bacteria and lignin-decomposing bacteria, and they can be appropriately selected and used according to the progress of composting. Thermophilic bacteria that can be used include Bacillus and Geobacillus, and cellulolytic bacteria include Penicillium and Gliocladium. Microorganisms exhibiting lignin degrading activity include fungi contained in the genus Ketomium.

In carrying out the method of the present invention, it is necessary to cut back in order to adjust the oxygen content and water content of the ridge.
The turning back can be performed manually or by using a stirrer such as a compost turner, which is a commonly used method.
The frequency depends on the temperature change of the fermentation ridge, but usually 1-2 months a month.
About once is desirable. Also, when turning back, remove water from the ridges by 5
It is preferable to adjust the content to be 0 to 60% by weight.

[0018]

EXAMPLES Next, the present invention will be described more specifically with reference to Examples and Comparative Examples. The root cuts were crushed by a crusher called a tab grinder to produce 0.1 to ³ inch size chips of about 100 m ³ . This root cut chip is divided into 4 ridges at a rate of 25 m ³ per ridge, and the first ridge is rice bran (1
0 kg / m ³ ) only, rice bran (10 kg / m 2) in the second ridge
m ³⁾ and added lime nitrogen (4.8kg / m ^3), the third ridges added bran (10kg / m ^3), the fourth ridges added to rice bran (10 kg / m ³⁾ Further, a bacterium of the genus Geobacillus, which is a thermophilic bacterium, was inoculated, and the water content of each ridge was adjusted to 60% by weight before ridge construction.

For the purpose of oxygen supply and water content adjustment, cutting was performed once a month. Hydration was also performed when necessary when turning back. The fourth ridge was inoculated with a cellulolytic bacterium 3 months after the ridge construction and a lignin degrading bacterium 5 months after the ridge. In such a situation, 4 ridges were deposited for 6 months. At the same time, the temperature of the ridges (the temperature inside the ridges about 50 cm from the top of the ridges) was measured once or twice a week for the purpose of roughly understanding the condition of the ridges.

The comparison of the four ridges was first carried out with respect to the ridge temperature. As shown in FIG. 1, the first ridge not inoculated with the thermophilic bacterium was used.
The maximum temperature of the ridges from No. 3 to No. 3 remained in the range of 60 ° C, but only the maximum temperature of the fourth ridge inoculated with the thermophilic bacterium was 81.
It rose to 5 ° C. In order to kill pathogenic bacteria and weed seeds, maintaining a high temperature condition (70-80 ° C) with good reproducibility and stability is essential for producing high-quality compost, so inoculation of thermophilic bacteria is effective. Considered a technique. In addition, from the results of compost analysis (shown in Table 1), it is generally said that the bark compost standard is that the pH is around neutral, the carbon content is large, and the C / N ratio is 35 or less. It can be seen that the ridge has a significantly higher degree of maturity in composting than the other ridges. Therefore, it was shown that inoculation of cellulose-decomposing bacteria and lignin-decomposing bacteria is also a useful method for compost production. Further, although not shown, good results were also obtained when the waste beech spore bed was further added to the fourth ridge.

Further, as shown in Table 2, a germination test of Komatsuna seeds was carried out, and it was confirmed that the compost had no quality problem. The germination test method will be described below. Raw sample 1 of each of the above-mentioned first to fourth ridge composts
0 g of each was placed in a 200 ml Erlenmeyer flask, 100 ml of boiling water was added, and the flask was covered with an aluminum foil. After standing for 1 hour, 2 pieces of gauze were stacked and filtered, and 10 ml of this filtrate
Was dispensed into a petri dish on which two pieces of filter paper had been laid in advance. On the other hand, as a control, water 10 once boiled
Dispense into a petri dish in the same manner as above using ml. 30 seeds of komatsuna seeds were sown in each of these 5 petri dishes, each petri dish was covered with the lid and kept at room temperature, and after 3 days, the germination rate and the state of the roots were observed.

[0022]

[0023]

[0024]

As described above, according to the present invention, the composting of the woody material can be performed in a short period of time.

[Brief description of drawings]

FIG. 1 is a diagram showing a temperature change in a composting process.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Ei Teranishi             4-2-7 Shinkaimachi, Tomakomai City, Hokkaido             In ceremony company Hokuhai F-term (reference) 4B065 AA57X AC02 AC15 AC20                       BB26 BC32 BC33 BC34 BC35                       BC42 BC50 CA55                 4D004 AA12 BA04 CA04 CA18 CB13                       CC03 CC07 CC15 DA02 DA09                 4H061 AA02 CC47 CC60 EE66 GG48

Claims (2)

[Claims] 1. A ridge in which a wood-based material is deposited, and a thermophilic bacterium,
A method for composting a wood material, comprising adding a cellulolytic bacterium and / or a lignin degrading bacterium. 2. The method for composting a wood material according to claim 1, further comprising a mushroom fungus bed.