JP3064221B2 - Aerobic bacteria and sludge treatment using the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for fermenting raw sludge, animal dung, and the like, particularly sludge obtained from municipal wastewater, by allowing a cell culture grown at a temperature of 85.degree. The present invention also relates to an aerobic bacterium or a mixed bacterium thereof suitable for use in this treatment method. The fermented sludge treated by the method of the present invention is usefully used as an organic fertilizer.

[0002]

2. Description of the Related Art Conventionally, livestock dung, human waste, sludge, municipal waste, etc.
Of fertilizer production from organic waste is well known
I have. For example, by treating these wastes with thermophilic microorganisms
This is fermented aerobically, deodorized, dried and transformed into compost
There is a way to make it happen. And with such thermophilic microorganisms
And Thermoactinomyces or Thermomonospora
A method using a thermophilic bacterium belonging to the group (JP-A-55-121992)
Publication), thermophilic aerobic spores such as Bacillus bacteria and lactic acid producing bacteria
Method using a mixture of forming bacteria (JP-A-51-129759)
 , A genus of thermus actix with lignin solubilizing ability
(Thermusaguaticusbiovar) (JP-A-6-105
No. 679) or aerobic fibrinolytic bacteria clost
Rhidium Thermoselm(Clostridium thermocellu
m) (JP-A-6-191977) and the like are known.
ing. In addition, the organic waste as described above is
Fermentation, and the raw material of shellfish, insects and mollusks
Mix body, crust, processing residue, etc.
Fermentation process while blowing air with the action of soil bacteria of the genus
Organic fermented fertilizer rich in chitosan
There is also known a method for producing a raw material (see JP-A-3-228888).
See). However, these methods use fermentation heat during fermentation.
Although the fermentation temperature rises to 70 ° C or higher,
It stays at 80 ° C at most and kills bacteria, especially spore-forming bacteria
It could not be destroyed. In the obtained fertilizer
The number of useful cells is at most 100 g / g (dry fertilizer)
When used as a fertilizer
Could not be done. Also, animal dung such as cow dung
When grass is used as a fermentation material, grass seeds mixed in it
Can not completely kill children, etc., used as fertilizer
Had caused weeds.

[0003]

The present inventors have paid attention to these problems in sludge treatment, and killed various bacteria and grass seeds by fermenting sludge at a high temperature of 85 ° C. or higher, preferably 95 ° C. or higher. Then, the sludge was sterilized and purified, and a study was conducted to obtain a fermented product containing many useful viable cells. In particular, microbial sources were searched to ferment sludge at such a high temperature of 85 ° C. or higher and find useful microorganisms in fertilizers. As a result, such bacteria were found from the soil of the Kirishima volcanic belt and the soil of the paddy field in the vicinity, and fermentation was performed by adding this to sludge. The present inventors have found that it can be converted to high organic fermentation fertilizer, and have completed the present invention. That is, the present invention decomposes sludge by fermenting sludge at a temperature of 85 ° C. or higher using a culture of a specific thermophilic bacterium, and kills and sterilizes germs, seeds, and the like growing therein. It is another object of the present invention to provide a sludge treatment method capable of growing a number of useful bacteria. Further, another object of the present invention is to provide a method of using clean sludge containing a large number of useful microbial cells fermented by such a method as an organic fertilizer. Further, an object of the present invention is to provide a useful microbial cell involved in such fermentation.

[0004]

SUMMARY OF THE INVENTION The present invention was made to solve such a problem, the raw sludge,
Obtained from the volcanic zone of the soil, a particular belonging to the server Chirusu the genus
Mix with a cell culture containing an aerobic bacterial mixture,
Fermentation under aerobic conditions at above temperature to convert raw sludge into organic fertilizer
To a sludge treatment method . Further, the present invention relates to a feature belonging to the genus Bacillus used for such processing.
A defined aerobic bacterium or a mixture thereof . Of the present invention
Specific aerobic bacteria belonging to the genus Bacillus include industrial technology
Accession No. F deposited at the Institute of Biotechnology and Industrial Technology
ERM P-15085, FERM P-15086 and / or FERM P-15086
Can be mentioned . The aerobic bacterial culture belonging to the genus Bacillus in the present invention and growing at a temperature of 85 ° C. or higher is a soil in the sulfur zone at 37 to 40 ° C. in the Kirishima volcanic belt in Makion-cho, Aira-gun, Kagoshima Prefecture, and the growth of blue moss in the same county. Sucrose aqueous solution was added to the mixture, and the mixture was added at 40 to 60 ° C for 3 to 1
Ferment for 5 days. Next, the fermented in this manner is mixed with raw sludge and fermented aerobically. And 85 ° C
It can be obtained by selectively collecting cultures fermented at the above temperatures. The sludge in the present invention includes not only sludge of so-called municipal wastewater (sewage) but also livestock dung, poultry dung, night soil, municipal waste and the like. In the present invention, these are called sludge.

[0005] A large number of mesophilic aerobic spores, thermophilic aerobic spores and thermophiles are isolated from the Bacillus cell culture thus obtained, and these separate the raw sludge of the present invention into high temperature. It is considered that the fermentation produces an effect of fermentation by exothermic fermentation. That is, the main microorganisms interposed in the sludge fermentation product in the present invention were searched. First, the viable cell count of the specimen was measured using various media. Table 1 shows the results.

[0006]

[Table 1] Number of viable bacteria per g of sludge fermented product ─────────────────────────────────── agar Number of viable bacteria per gram of culture medium cultivated ──────────────────────────────────── Resistance Fungicide-added SCD 30 ° C for 3 days Aerobic Aerobic bacteria 9.9 × 10 ⁸ Antifungal-added SCD 55 ° C for 3 days Aerobic Thermophilic bacteria 8.4 × 10 ⁷ Antifungal-added SCD 30 ° C for 3 days Aerobic Heat-resistant spores ^* 2.8 × 10 ⁷ DHL 35 ° C 1 day Aerobic Intestinal bacteria 100 or less CVT 30 ° C with antifungal agent 3 days aerobic Gram-negative bacteria 100 or less Columbia CNA 30 ° C with antifungal agent 3 days Aerobic Gram-positive bacteria 2.8 × 10 ⁶ Antifungal agent added MRS 30 ° C 3 days Anaerobic Lactic acid bacteria 100 or less Antifungal agent added Gentamicin added GAM 35 ° C 3 days Anaerobic Anaerobic bacteria 100 or less Antifungal agent added Albumin 30 ° C 14 days Aerobic Mesophilic radioactive bacteria 1.1 × 10 ³ antifungal agent addition albumin 55 Aerobic 14 days Thermophilic actinomycetes 6.0 × 10 ² thread-like fungi 100 or less Kuroramu 25 ° C. 7 days aerobically ───────────── fenicol pressure PD yeast than 100 ───── ─────────────────────────────── * However, the test was performed after heat treatment at 80 ° C. for 10 minutes.

[0007] As shown in Table 1, the sludge fermentation product contained about 1 billion bacteria per gram sludge fermentation product, mainly aerobic bacteria, thermophilic bacteria and heat-resistant spores. next,
In the above culture, colonies predominantly grown on the culture plate were hooked to obtain isolated bacteria, and the isolated bacteria were observed for morphology and the like. Intermediate microorganisms were determined from their properties. Table 2 shows the results.

[0008]

[Table 2] Major intervening microorganisms in sludge fermentation products Approximately ────────────────────────────── polymorphic, spore-free gram-positive bacilli 7 × 10 ⁸ aerobic spores mesophilic 3 × 10 ⁸ High temperature 8 × 10 ⁷ Catalase-positive gram-positive cocci 1 × 10 ⁷ Actinomycetes Medium temperature 1 × 10 ³ High temperature 6 × 10 ² ──────────────── ──────────────

[0009] As shown in this table, it was found that polymorphism, spore-free gram-positive bacilli, and aerobic spores (medium- and hyperthermic) were mainly involved. On the other hand, R & D planning issued by Kazuhide Yamazato and three others, "Microbial isolation method"
The thermophilic bacterium was measured with reference to the description of the above. Table 3 shows the results. The dominant thermophilic bacterium was aerobic spore bacterium (thermophilic).

[0010]

[Table 3] Measurement results of thermophilic bacteria ───────────────────────── Cultivation results of liquid medium ─────────培 地 A medium 70 ° C, 3 days positive / 0.1g B medium 70 ° C, 3 days positive / 0.01g ──────────── ─────────────

The medium A is a medium adjusted to pH 7.5 by adding 0.1% of peptone and 0.1% of yeast extract to a basal salt solution, and the medium B is 0.8% of peptone, 0.4% of yeast extract and 0.4% of basal salt solution. This medium is adjusted to pH 7.5 by adding 0.3% NaCl.

Furthermore, mesophilic aerobic spores (isolated bacteria a) (see Table 2), thermophilic aerobic spores (isolated b) (see Table 2), and phytophilic aerobic spores which were predominantly isolated in the search for the microorganisms described above. With respect to the thermophilic bacterium (isolated bacterium c) (see Table 3), morphological observation, physiological property test, and measurement of GC content of DNA in the bacterium were performed. The results are shown in Tables 4 and 5.

[0013]

[Table 4]

[0014]

[Table 5]

[0015] Based on this result, "Bergey's Manual of
Systematic Bacteriology "Volume 2 (1986) and US
Published by Department of Agriculture RE Gordon et al. "T
heGenus Bacillus "(1973). The isolated bacterium a did not match the properties of any of the species described in the above literature, and the species was not determined. Showed good growth in a slightly alkaline medium (pH 8.0-8.5) and did not grow at pH 7.0, but it was considered to be a species close to Bacillus badius and B. brevis from other properties. The properties of B. badius and B. brevis described in the above Bergey's Manual are shown in Table 5 together with the atypical properties of both, and the isolate c. , Bacillus stearothermophilus and ( Bacillus stearothermophilus ) were identified as having the same mycological properties and being homologous.These isolates have been deposited with the National Institute of Biotechnology, Is YM-01 accession number FERM P-15085, isolate b is YM-02 accession number FERM P-15086, The isolate c has YM-03 accession number FERM P-15087 and accession number respectively.

In the sludge treatment method of the present invention, first, raw sludge as described above is mixed with a cell culture.
The cell culture is preferably 30 to 20 parts by weight per 80 to 100 polymerization parts.
The mixture is put into a fermentation yard and left while blowing air to perform aerobic fermentation. In this way, the mixture, which was initially at room temperature, will reach a temperature of 85 ° C. or more after one to several days. The fermentation is carried out by leaving the mixture at this temperature for about 2 to 5 days, and switching is performed. This operation of leaving fermentation and turning over is performed 3 to 5 times, and fermentation is performed for about 20 to 50 days, and the sludge becomes a dry and dry state. The dried product is optionally sieved and packaged. This is useful as an organic fertilizer. Further, in the dried product obtained as described above, the isolated bacteria a, b and c belonging to the genus Bacillus described above.
Can be recycled as a cell culture.

[0017]

Next, the present invention will be specifically described with reference to examples.

[Example 1] (1) Preparation of bacterial cell culture 37-40 in the sulfur zone of the Kirishima volcanic belt in Makion-cho, Aira-gun, Kagoshima Prefecture
℃ soil and the soil where the green moss growing in the paddy field near it is mixed, and 3-4 L of an aqueous sucrose solution in which sucrose is dissolved in 500-1000 times the amount of water is added per 1 m ³ of the soil mixture. 60
Incubate at 30 ° C for 30-50 days. The culture was divided into several lots, mixed with raw sludge, and fermented under aerobic conditions while blowing air into the lot. A lot having a fermentation temperature of 85 ° C. or higher was obtained as a cell culture.

(2) Treatment of raw sludge Deodorizing treatment is carried out by adding slaked lime to a mixture of animal feces, sewage sludge, starch scum and garbage, and 80 parts by weight of the cell culture obtained in (1) above. Then, 20 parts by weight of the mixture are mixed and fermentation is performed in a fermenter under aeration conditions. In this way, the fermented product rises from room temperature to 85 ° C. to 95 ° C. in about one day. The fermentation is maintained at this temperature for three days, and the fermentation is repeated (stirring) on the fifth day after the start of fermentation. By switching, the temperature of the fermented product drops to around 60 ° C, but rises to 85-95 ° C in about one day.
Fermentation is carried out at this temperature for 5 days. When this operation of fermentation and switching is repeated several times, the temperature at the time of switching and the fermentation temperature gradually decrease. This operation is repeated four times, and the time when the temperature of the fermented material at the time of cutting back falls to about 35 ° C. is defined as the final fermentation date. The obtained fermented product is dried to form brown granules, and this is used as it is as an organic fertilizer. The thus obtained product contains about 1 billion isolates a, b and c belonging to the genus Bacillus, and can be used repeatedly in the present invention as a cell culture.

[0019]

Example 2 About 6 tons of the cell culture obtained in Example 1 (2) was mixed with 30 tons of cow dung, and this mixture was placed in a fermenter.
Air was blown from the bottom. Fermentation initial temperature is 30 ~
The temperature was 35 ° C, but rose to 75 to 80 ° C for 2 days after the start of fermentation and to 85 to 90 ° C for 3 days. When the temperature was maintained at this temperature for 2 days and the fermentation temperature showed a tendency to decrease, the fermentation was repeated, fermentation was similarly performed for 4 days, repetition was repeated, and fermentation was performed in the same manner to obtain a black-brown dry powder. This dry powder,
It was suitable as an organic fertilizer.

[0020]

[Example 3] The public sewer sludge of Kagoshima City is squeezed and dewatered,
Example 1 (2) for 80 parts by weight of raw sludge with a water content of 68%
Was mixed into a fermentation yard, and fermentation was performed while blowing air from below. Seven days after the start of fermentation, the temperature reached 98 ° C. Fermentation was performed for 10 days, and when the fermentation temperature began to decrease from 98 ° C., the fermentation was repeated and fermentation was performed again. After reaching a temperature of up to 99 ° C, ie 10 days after turning back, the temperature rapidly rises to 60-70 ° C
Has dropped. At this point, the fermentation product was spread in the fermentation yard, and the temperature was rapidly lowered to room temperature to obtain brown sludge fermentation powder. Temperature measurement during the fermentation period was performed at three points as shown in FIG. 4 in the fermentation yard. The result is shown in FIG. Table 6 shows the analysis results of the raw sludge and the sludge fermentation powder.

[0021]

[Table 6] 1) Measurement conditions: temperature, 100 ° C; time, 5 hours 2) According to “Analytical Methods for Fertilizers”, Agricultural and Environmental Technology Research Institute, Ministry of Agriculture, Forestry and Fisheries. However, the value is for dry sample. 3) Measurement conditions: temperature, 550 ° C; constant weight 4) Measuring equipment: CHN Coder-MT-5 [manufactured by Yanagimoto Seisakusho Co., Ltd.]. However, those dried at 70 ° C. for 15 hours were tested. 5) Values for dry samples. As can be seen from this table, the raw sludge fermented powder has a general bacteria count of 1.6 billion / g despite being treated at a fermentation temperature close to 100 ° C. Is determined to be used.

[0022]

According to the method of the present invention, sludge is fermented at a temperature of 85 ° C. or higher using specific thermophilic cells, so that the ferment is fermented so as to be suitable as a fertilizer component. In addition, various bacteria, seeds, and the like are killed by such high temperature, and only a large number of bacteria useful as fertilizers are present, which makes them suitable as fertilizers.

[Brief description of the drawings]

FIG. 1 shows a micrograph of the isolated bacteria a.

FIG. 2 shows a micrograph of the isolated bacterium b.

FIG. 3 shows a micrograph of the isolated bacterium c. All were stained with spores and the magnification was 2,000 times.

FIG. 4 shows temperature measurement points (, and) of a sludge fermentation product in the fermentation yard of Example 3. 1 is a sludge fermentation product.

FIG. 5 shows a temperature measurement result of Example 3.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) C05F 1/00-17/02 B09B 3/00 C02F 11/18 C12N 1/20

Claims (2)

(57) [Claims] Claims: 1. A biotechnological laboratory belonging to the genus Bacillus.
Science and Technology Research Institute accession number FERM P-15085, FERM P-150
86 and at least one selected from the group consisting of FERM P-15087
And at least one aerobic bacterium or a mixture thereof . 2. Raw sludge obtained from soil in a volcanic zone,
The aerobic bacteria mixture according to claim 1, which belongs to the genus Bacillus.
Aerobic conditions at temperatures above 85 ° C
The raw sludge is turned into organic fertilizer by fermentation under
Sludge treatment method .