JP3436859B2 - Microorganism and sludge treatment method using the same - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a thermophilic bacterium, a thermophilic aerobic spore bacterium or a mesophilic aerobic spore bacterium used for treating raw sludge, animal feces, etc., particularly sludge obtained from municipal wastewater, or these. Of mixed cells of. Further, the present invention is
The present invention relates to a sludge treatment method of reacting raw sludge, animal feces, etc., particularly sludge obtained from municipal wastewater, with the above-mentioned cell culture that grows at high temperature to perform fermentation treatment at high temperature to convert sludge into organic fertilizer.

[0002]

2. Description of the Related Art Conventionally, livestock manure, human waste, sludge, municipal waste, etc.
To make fertilizer from organic waste in the world is well known
There is. For example, let these thermophiles act on these wastes
Aerobically fermented it, deodorized and dried to convert it into compost
There is a way to do it. And with such thermophilic microorganisms
Then Thermoactinomyces or Thermomonospora
Using thermophilic bacterium belonging to
Gazette), thermophilic aerobic spores of Bacillus, lactic acid producing bacteria, etc.
Method using mixture of forming bacteria (JP-A-51-129759)
 , Lactin Solubilizing Thermus Actix
(Thermusaguaticusbiovar) Is used (Japanese Patent Laid-Open No. 6-105
No. 679) or aerobic fiber-degrading bacterium closto
Rejumum Thermoselm(Clostridium  thermocellu
m) Is used (Japanese Patent Laid-Open No. 6-191977) and the like are known.
ing. In addition, the organic waste as described above can be treated with thermophilic bacteria.
Fermented to give raw crustaceans, insects and molluscs.
Heterotroph is mixed with the body, skin, and processing residue.
Fermentation process by blowing on air by acting on soil bacteria of the genus
Organic fermented manure rich in chitosan
There is also known a method for producing a material (Japanese Patent Laid-Open No. 3-228888).

However, in these methods, although the fermentation temperature rises to 70 ° C. or higher due to the heat of fermentation during fermentation, the temperature remains at most 80 ° C., and it is impossible to kill various bacteria, especially spore-forming bacteria. In addition, the number of useful cells in the obtained fertilizer was at most about 100 million per 1 g (fertilizer dry matter), and the fertilizing effect could not be sufficiently exhibited when used as a fertilizer. In addition, when animal dung such as cow dung is used as a fermentation raw material, grass seeds mixed therein cannot be completely killed, and when it is used as a fertilizer, weeds are caused. The present inventors have paid attention to these problems in sludge treatment,
℃ or more, preferably, to ferment sludge at a high temperature of 95 ℃ or more to kill miscellaneous bacteria and grass seeds, sterilize sludge to clean it, and study to obtain a fermented product containing many useful viable cells Was done.

In particular, the sources of microorganisms were searched for in order to find the microorganisms which ferment sludge at such a high temperature of 85 ° C. or higher and which are useful in fertilizers. As a result, when we found such bacteria in the soil of the Kirishima volcanic zone and the soil of the paddy field in the vicinity of the soil and added it to sludge and fermented it, it could be fermented at a high temperature of 85 ° C or higher, and A patent application was filed (patent application No. 7-234690) (hereinafter referred to as a prior application), finding that it can be converted to high organic fermented fertilizer. Also,
When the strains involved in this fermentation were searched, an aerobic bacterium belonging to the genus Batisul was found.

[0005]

Therefore, when further searching for this strain, sludge is fermented by these bacteria and reaches a high temperature of 85 ° C. or higher under aerobic conditions. We came to think that the thermophilic or mesophilic aerobic bacteria that form spores were largely involved in sludge fermentation, and when the sludge fermented product was still under high temperature, a sample was directly collected from the sludge fermented product. , The cells were separated. As a result, the thermophilic bacterium, thermophilic aerobic spore bacterium, and mesophilic aerobic spore bacterium involved in high temperature fermentation could be separated and identified. Further, when fermentation was carried out using this cell culture, the sludge could be fermented at high temperature and used as an organic fertilizer.

That is, the object of the present invention is to provide a novel thermophilic bacterium, thermophilic aerobic spore bacterium, mesophilic aerobic spore bacterium, or a mixed cell thereof which is capable of fermenting sludge at high temperature. To do. Another object of the present invention is to provide a method for treating sludge, which comprises fermenting sludge at a high temperature under aerobic conditions using these fungus bodies or a culture thereof to convert sludge into an organic fertilizer. The present invention collects this sludge fermented product as a sample when the sludge fermented product is under high temperature, and isolates and identifies thermophilic bacteria, spore-forming bacteria, etc. in which the high temperature is involved in fermentation.

[0007]

The present invention has been made in order to solve such a problem, and in the same manner as in the previous application, the raw sludge containing 85 ° C or more obtained from the soil of a volcanic area is used. A bacterial culture belonging to the genus Bacillus that grows at temperature is added at high temperature, mixed, and aerated to a fermentation temperature of 85 ° C.
I raised it above. Belongs to the genus Bacillus in the present invention, 85 ℃
The aerobic culture that grows at the above temperature is a mixture of the soil in the sulfur zone of 37-40 ° C in the Kirishima volcanic zone of Makizono-cho, Aira-gun, Kagoshima prefecture, and the soil of the paddy field in which the green moss grows. Then, a sucrose aqueous solution is added to this mixture and the mixture is fermented at 40 to 60 ° C. for 3 to 15 days. Next, the thus fermented product is mixed with raw sludge and aerobically fermented. It was obtained by selectively collecting sludge that fermented at a temperature of 85 ° C or higher while it was hot. The sludge in the present invention includes not only sludge of so-called municipal wastewater (sewage) but also livestock manure, poultry manure, human waste, municipal waste, and the like. In the present invention, these are called sludge.

In the present invention, when the raw sludge fermented product is at a high temperature, the sludge fermented product is collected as a sample, and thermophilic bacteria, high temperature to mesophilic bacteria, etc. are searched for. That is, after measuring the viable cell count of the sample using various media, the colonies that grew predominantly on the culture plate were picked up as isolated cells,
Morphological observation and the like were performed for each isolate. In addition, thermophilic bacteria were measured with reference to the method for separating microorganisms (“Method for separating microorganisms” edited by Kazuhide Yamazato, published by R & D Planning in 1986). As a result, 1g of sample measured using various media
The viable cell count per unit is shown in Table 1.

[0009]

[Table 1]

Table 2 shows the main intervening microorganisms in the sample, based on the results of measuring the viable cell count of the sample and the properties of the isolates obtained by fishing the colonies that predominantly grew on each culture plate. It was

[0011]

[Table 2] Main intervening microorganisms in the sample ──────────────────────── Approximate number of isolated bacteria per 1g ─────── ───────────────── Aerobic spore bacterium Mesophilic 1 × 10 ⁸ High temperature 1 × 10 ⁸ Actinomycete Mesophilic 7 × 10 ² High temperature 2 × 10 ² ── ──────────────────────

Table 3 shows the measurement results of thermophilic bacteria among them. The thermophilic bacterium was aerobic spore bacterium (thermophilic).

[0013]

[Table 3] Thermophilic bacterium measurement results ───────────────────────── Liquid medium culture results ────────── ──────────────── A 70 ℃, 3 days Negative / 0.1g B 70 ℃, 3 days Positive / 0.001g ────────────── ─────────── * Tested with reference to the method for separating microorganisms. Liquid medium A is a medium adjusted to pH 7.5 by adding 0.1% peptone and 0.1% yeast extract to the basal salt solution, and liquid medium B is 0.8% peptone, 0.4% yeast extract and NaCl to the basal salt solution. The medium is adjusted to pH 7.5 with the addition of 0.3%.

Further, thermophilic bacteria (isolated bacteria a and b), thermophilic aerobic spores (isolated bacteria c and d) and mesophilic aerobic spores (isolated bacteria e) which were predominantly isolated in the search for the above microorganisms. , F and d) were subjected to morphological observation, physiological property test, and GC content of DNA in cells was measured. The results are shown in Tables 4-8.

[0015]

[Table 4]

[0016]

[Table 5]

[0017]

[Table 6]

[0018]

[Table 7]

[0019]

[Table 8]

Based on this result, "Bergey's Manual of
Systematic Bacteriology "Volume 2 (1986), US De
Published by part of Agriculture RE Gordon et al. "The G
The identification was performed with reference to "enus Bacillus" (1973) and the like.

It was found that the isolates a and b are gram-positive thermophilic bacilli that form thermostable spores and belong to Bacillus schlagelii . Isolate b is slightly alkaline (pH
It shows good growth in the medium of 8.0 to 8.5) and does not grow at pH 7.0, but other properties test results indicate that Bacillus badius and
It seems to be a species close to B. brevis . However, both of them had atypical properties and could not be classified into these species. Described in the Bergey's Manual above
The properties of B. badius and B. brevis are also shown in Table 5.

Moreover, isolates c is, Bacillus BAdI etc. that VP reaction does not produce an acid from glucose negative
It seemed to be a species close to us and B. brevis , but the characteristics were not completely in agreement with any of the bacterial species. Characterization test result of isolate c and literature of B. badius and B. brevis (above Bergey's Ma
Table 5 shows the description of "Nual of Systematic Bacteriology vol.2 (1986)", and Table 6 shows the result of the property test of the isolated microorganism d.

All of the isolates e, f and g were identified as bacteria belonging to Bacillus . However, the isolate e is B. badiu
Although it showed a property very close to s , the GC content of intracellular DNA was different. Isolated bacterium f was considered to be a species close to B. circulans and B. lentus because it had a negative VP reaction and did not grow at 50 ° C, but the characteristics were not completely in agreement with any of the bacterial species. In addition, the isolated bacterium g also showed properties similar to B. badius, but they differed in that the GC content of intracellular DNA was as low as 38% and that it did not grow at 50 ° C. Test results of isolates e and g and B. badius reference (above-mentioned Bergey's Manual of Systemat
ic Bacteriology vol.2 (1986)), and Table 8 shows the test results of the isolated fungus f and the references of B. circulans and B. lentus (the same magazine). Since the isolated bacteria did not grow in some of the property test media, these tests were performed by adding a sample leachate to the media.

These isolates a to g have been deposited at the Institute of Biotechnology, Institute of Industrial Science and Technology. Isolate a is YM
-04 Accession number FERM P-15536, isolate b is YM-05 Accession number FERM P-15537, isolate c is YM-06 Accession number FERM P-1
5538, isolate d is YM-07 accession number FERM P-15539, isolate e is YM-08 accession number FERM P-15540, isolate f is YM
-09 The accession number FERM P-15541 and the isolated strain g are assigned with the accession numbers YM-10 accession number FERM P-15542, respectively.

In the sludge treatment method of the present invention, first, the above-mentioned raw sludge is mixed with the bacterial cell culture at a high temperature. The mixing ratio is
30 to 20 parts by weight of cell culture is preferable to 70 to 80 parts of raw sludge. This mixture is put into a fermentation yard and left to stand while blowing air to perform aerobic fermentation. In this way, the mixture, which was initially at room temperature, will be 85 ℃ after 1 to several days.
It becomes the above temperature. It is left to stand at this temperature for about 2 to 5 days to ferment it and cut into pieces. If this fermentation and leaving operation are carried out 3 to 5 times and fermentation is carried out for about 20 to 50 days, the sludge will be in a dry and dry state. The dried product is optionally screened and packaged. This is useful as an organic fertilizer. In addition, in the dried product obtained as described above, the isolates a to
Since g is grown, it can be circulated as a cell culture while hot.

[0026]

BEST MODE FOR CARRYING OUT THE INVENTION 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 area of the Kirishima Volcanic Zone, Makizono-cho, Aira-gun, Kagoshima Prefecture
℃ soil is mixed with the green moss growing in the rice paddies in the vicinity, and sucrose aqueous solution prepared by dissolving sucrose in 500 to 1000 times amount of water is added to the soil mixture in an amount of ^{3 to 4} L per 1 m ³ of soil mixture, and 40 to 40 60
Incubate for 30-50 days at ℃. This culture was divided into several lots, mixed with raw sludge, and fermented under aerobic conditions while blowing air, and a lot from which a fermentation temperature of 85 ° C or higher was obtained was used as a cell culture.

(2) Treatment of raw sludge Deodorizing treatment was performed by adding slaked lime to a mixture of animal feces, sewage sludge, starch dregs and raw garbage, and 80 parts by weight of the microbial cell culture obtained in the above (1) 20 parts by weight of the product is mixed with a product having a fermentation temperature of 80 ° C or higher, and fermentation is carried out in a fermenter under aeration conditions. In this way, the fermented material will be heated from room temperature to 85 ℃ ～ 95 in about 1 day.
Rise to ℃. Fermentation is maintained at this temperature for 3 days, and turning back (stirring) is performed 5 days after the start of fermentation. By turning back, the temperature of the fermented material decreases to around 60 ° C, but rises to a temperature of 85 to 95 ° C in about one day. Fermentation is carried out at this temperature for 5 days. When this operation of fermentation and turning back is repeated several times, the temperature at the time of turning back and the fermentation temperature gradually decrease. This operation is repeated four times, and when the temperature of the fermented product at the time of turning back drops to about 35 ° C, the final fermentation day is set.
The obtained fermented product is dried into brown granules, which are used as they are as organic fertilizers. The thus-obtained product contains about 1 billion cells of the Bacillus genus described above, and can be repeatedly used in the present invention as a cell culture.

[0028]

Example 2 About 6 tons of the bacterial cell culture in the hot state obtained in Example 1 (2) was mixed with 30 tons of cow dung, the mixture was put into a fermenter, and air was blown from the bottom thereof. The temperature at the beginning of fermentation was 30-35 ℃, but for 2 days after the start of fermentation,
The temperature rose to 75 to 80 ° C and 85 to 90 ° C for 3 days. 2 at this temperature
When it was maintained for a day and when the fermentation temperature tended to decrease, it was cut back, fermented for 4 days in the same manner, cut back again and fermented in the same manner to obtain a black-brown dry powder. This dry powder was suitable as an organic fertilizer.

[0029]

[Example 3] The public sewer sludge of Kagoshima City was squeezed and dehydrated,
Example 1 (2) against 80 parts by weight of raw sludge having a water content of 68%
20 parts by weight of the microbial cell culture in a hot state obtained in step 2 were mixed, placed in a fermentation yard, and fermented while blowing air from below. The temperature reached 98 ° C 7 days after the start of fermentation. Ten
Fermentation was carried out for a day, and when the fermentation temperature began to drop from 98 ° C., it was cut back and fermented again. Up to 99 ° C
The temperature rapidly dropped to 60-70 ° C after reaching the temperature of 10 ° C, that is, 10 days after turning back. 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.

[0030]

According to the method of the present invention, sludge is fermented using specific thermophilic cells at a temperature of 85 ° C. or higher, so that the fermented product is fermented so as to be suitable as a fertilizer component. Further, such high temperature kills various bacteria, seeds and the like, and there are only many bacteria useful as fertilizers, which makes them suitable as fertilizers.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI C05F 7/00 C05F 7/00 // (C12N 1/20 C12N 1/20 C12R 1:07) C12R 1:07 (58) Survey Areas (Int.Cl. ⁷ , DB name) C12N 1/20 C02F 11/02 C05F 3/00 C05F 7/00 BIOSIS / WPI (DIALOG)

Claims (3)

(57) [Claims] 1. The Institute of Life and Industrial Technology, Institute of Industrial Science and Technology, which belongs to the genus Bacillus and is capable of aerobically fermenting raw sludge at a temperature of 85 ° C. or higher to produce dried granular or powdery organic fertilizer. Consignment number FERM P-15536, FERM P-15537, FERM
P-15538, FERM P-15539, FERM P-15540, FERM P-15541
And a mixed aerobic bacteria represented by FERM P-15542. 2. Granules obtained by mixing raw sludge with the culture of the mixed bacterial cells according to claim 1 while the culture is hot and fermenting the mixture at 85 ° C. or higher under aerobic conditions to dry the raw sludge. To a powdered organic fertilizer, which is a sludge treatment method. 3. The sludge treatment method according to claim 2, wherein the raw sludge is sludge obtained from municipal wastewater or animal dung.