JP2000186272A - Injurious compound decomposer, method of treating polluted material and apparatus for treating polluted material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a decomposer for injurious compounds (e.g. dioxin), a method of treating polluted materials, and an apparatus for treating polluted materials. SOLUTION: A decomposer for injurious compounds comprises a microorganism having decomposability of injurious compounds and an activation substance for the microorganism (e.g. a ligneous substance, a surface active agent, veratric alcohol, a metallic ion or a nutrient material having pH adjustability). A method of treating polluted materials comprises treating materials polluted with injurious compounds in the presence of microorganisms having the decomposability for injurious compounds and an activating substance for the microorganisms. A treating apparatus comprises a reactor, a means to agitate materials polluted with injurious compounds in the reactor, a means to introduce air into the reactor, a temperature controlling means, a pH controlling means, and a water content controlling means.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a harmful compound decomposing agent, a method for treating contaminated materials, and an apparatus for treating contaminated materials. ADVANTAGE OF THE INVENTION According to this invention, the harmful compound (especially dioxin) which exists in incineration ash and soil contaminated by harmful compounds (especially dioxin) is effectively decomposed and / or
Or it can be reduced.

[0002]

2. Description of the Related Art In recent years, dioxins generated in waste incineration facilities have become a problem. This dioxin is present in the incineration main ash, which is the residue of incineration, and in the incineration fly ash discharged together with the exhaust gas. If this incineration fly ash is not properly treated with a bag filter or the like in the incineration flue, dioxin will be released into the environment, and this problem is particularly noticeable in small incineration facilities. . Also, as for incineration main ash and incineration fly ash collected in the incineration facility and buried in the final disposal site, leaching of rainwater or the like results in release of dioxin in the ash to the environment. Dioxin released into the environment in this way is accumulated in the human body through the food chain and the like, and there is a concern that the carcinogenic and teratogenic effects may occur.

[0003] Dioxin decomposition treatment methods include a complete combustion method (melt solidification method), a thermal decomposition method (heat dechlorination method), a pelletizing firing method, a photolysis method, and various chemical decomposition methods. And supercritical water treatment methods and the like have been reported. Techniques for decomposing dioxins using microorganisms have also been reported. For example, Pseudomonas (Pse
(Klekka, G. et al., Decomposition of dibenzoparadioxin using bacteria belonging to the genus Udomonas). M.
And Gibson, D.A. T. , Biochem. J. ,
180, 639-645 (1979)] and white-rot fungi (Fanelocate chrysosporium: Phanero).
Example in which 2,3,7,8-tetrachlorodibenzoparadioxin was decomposed using chaete chrysosporium [Bumpus, J. et al. A. Et al., Sci
ence, 228, 1434-1436].

Among them, white-rot fungi have a wide substrate specificity of enzymes involved in the decomposition and secrete enzymes involved in the decomposition such as lignin peroxidase and manganese peroxidase out of the cells, so that many of them are hardly soluble in water. It can be applied to harmful compounds related to environmental pollution. Also,
White rot fungi actively secrete these enzymes in environments with low nitrogen concentrations, so there is no need to add many nitrogen sources during culture [Barr, D .; P. And Aust, S .;
D. , Environ. Sci. Technol. 28
(2), 78A-87A (1994)].

[0005] Dioxin decomposition technology using such microorganisms does not require expensive treatment equipment as in the prior art such as the above-described complete combustion method, and can carry out treatment in accordance with the amount of contaminated materials, resulting in cost reduction. In addition to being considered to be excellent in terms of operability and operability, it is very difficult to treat harmful compounds such as dioxin released widely into the environment according to the above-mentioned conventional technology, while using microorganisms. In recent years, attention has been paid to the fact that it can be implemented without such difficulties by using the conventional processing technology.

[0006]

However, most of the conventional biodegradation methods are applied to dioxins in a solution, and detoxify dioxins in contaminated materials such as contaminated incinerated ash and contaminated soil. Could not. Also,
Because there were unclear points about various conditions when applying the microbial decomposition method to dioxin in contaminated materials such as contaminated incinerated ash and contaminated soil, and factors that improve the efficiency of dioxin decomposition by microorganisms, There has been no report on a dioxin decomposing agent, a dioxin decomposing method, a dioxin decomposing device, and the like.

Accordingly, the present inventors have developed a harmful compound decomposer which can be used to detoxify harmful compounds in contaminated materials such as contaminated incinerated ash and contaminated soil, and a method for detoxifying harmful compounds. As a result of intensive research on a method for treating contaminated materials and a device for treating contaminated materials, the following findings were obtained. That is, the present inventors carry microorganisms such as white rot fungi on a substrate such as wood flour and add them to contaminated materials, or enzymes secreted outside the cells from the microorganisms carried on the substrate. When a solution containing a group (for example, a culture solution) is added to the contaminated material, or when microorganisms such as white rot fungi are added to the contaminated material together with a substrate such as wood flour,
The present inventors have found that the activity of decomposing harmful compounds can be improved as compared with the case where a microorganism such as white rot fungus is used alone, and the above problem can be solved at low cost and easily. Dioxins contained in contaminated materials such as contaminated incineration fly ash and contaminated soil are oxidatively decomposed by enzymes generated from microorganisms such as white rot fungi. In addition, we have:
It has also been found that the use of the above method makes it possible to improve the decomposition activity and to secure a sufficient space for the growth of microorganisms.

[0008] A culture solution obtained by culturing the microorganism in a medium enriched with a specific metal element may be added to the contaminated material.
Alternatively, by adding a culture solution obtained by culturing the microorganism by adding veratryl alcohol or a surfactant to the contaminated material, the decomposition activity of the harmful compound is similarly improved as compared with the case of using the microorganism such as white rot fungus alone. It is possible,
It has been found that the above problem can be easily and cheaply solved.

Further, incinerated ash is generally basic, and the inside of the incinerated ash is subjected to severe conditions for the growth of microorganisms. The present inventors have found that even when the contaminated material to be detoxified is incineration ash, the pH of soil or compost (obtained by composting kitchen garbage or the like) having a pH buffering capacity is obtained.
By adding a control material at the time of treatment, it becomes possible to provide appropriate pH conditions and nutrients necessary for growth of microorganisms such as white rot fungi, and in terms of the growth environment of microorganisms, a wider range of contaminated materials can be provided. Can be processed.

[0010] Furthermore, the present inventors have found that when dealing with a large amount of contaminated materials, it is necessary to ensure optimal growth conditions for microorganisms and / or
Alternatively, the present inventors have also found a novel device that enables maintenance and maximizes the effectiveness of adding microorganisms or soil (or compost) supported on the substrate.

Further, since dioxin released into the environment exists in a relatively wide range at a low concentration, it is difficult to carry out conventional techniques such as the above-mentioned complete combustion method. The present inventor has found a method capable of decomposing dioxin relatively inexpensively, easily, and effectively even in such a case. The present invention is based on such findings.

[0012]

Accordingly, the present invention relates to a harmful compound decomposing agent comprising a microorganism having a capability of degrading harmful compounds and an activator of the microorganism. The present invention also provides a method for treating a harmful compound-contaminated material, which comprises treating the material contaminated with the harmful compound in the presence of a microorganism having the ability to degrade harmful compounds and an activator of the microorganism. Related. Further, the present invention provides
A reactor, means for stirring harmful compound contaminated materials in the reactor, means for introducing air into the reactor, temperature control means, pH control means, and water content control means. The present invention also relates to an apparatus for treating harmful compound contaminated materials.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, "harmful compounds"
Means a compound contained in incineration ash or soil and causing environmental pollution, for example, dioxin (ie,
Environmental hormones such as polychlorodibenzo-p-dioxin and polychlorodibenzofuran) and polychlorobiphenyl or biphenyl can be mentioned. In the present specification, “dioxin” refers to polychlorodibenzo-p-dioxin, which is a tricyclic compound having a structure in which two benzene rings are condensed via two oxygens, as described above. -Di
oxin), and polychlorodibenzofuran, which is a tricyclic compound having a structure in which two benzene rings are fused via one oxygen.

The microorganism used in the present invention is not particularly limited as long as it is a microorganism capable of decomposing (particularly oxidatively decomposing) the harmful compound (particularly dioxin).
For example, it is a microorganism capable of producing a harmful compound decomposing substance (especially an enzyme), and preferably a microorganism that produces a harmful compound decomposing substance (especially an enzyme) and releases it out of the cells. Specifically, microorganisms having the ability to decay wood (wood decay fungi), for example, Fanelocate chrysosporium (Ph
anerochaete chrysosporiu
m: hereinafter referred to as PC bacterium: IFO31249), or V2 bacterium obtained by screening from nature [Tachibana et al., Paper and Pulp Technical Journal, 50 (12), 122-131 (199)
6)] and the like. In addition, a microorganism that secretes an enzyme capable of oxidatively decomposing dioxin (eg, lignin peroxidase, manganese peroxidase, or laccase) can be used.

In the present invention, an activator of the microorganism (ie, an activator of the microorganism) is used. The microorganism activating substance is a substance that promotes the growth of the harmful compound-degrading microorganism, and in particular, promotes the growth of the harmful compound-degrading microorganism to enhance the ability to produce harmful compound-decomposing substances (for example, enzymes). It is a substance that improves the activity of decomposing harmful compounds. As the microorganism activating substance, for example, a woody substance can be used. As the woody substance, various shapes of wood (for example, wood flour or wood chips) or woody waste (for example, straw or wood chips), preferably wood flour can be used. By adding these woody substances, the decomposition activity of harmful compound-degrading microorganisms is improved, and a space for growing harmful compound-degrading microorganisms in the contaminated material to be treated is provided. In the present invention, the harmful compound-degrading microorganisms may be used together with the harmful compound-degrading microorganisms carried on the woody material, or the harmful compound-degrading microorganisms and the woody material may be used separately.

As a method of supporting harmful compound-degrading microorganisms on woody substances, for example, the method of Hiroi et al. [Biomass Conversion Planning Report, No. 1, 23-41 (198
6)] and the method of Yum et al. [Water. Enviro
n. Res. 70 (2), 205-213 (199
8)], harmful compound-degrading microorganisms (for example, microorganisms having dioxin decomposability) are cultured together with wood flour or wood chips in a suitable medium, and the harmful compound-degrading microorganisms are cultivated with the wood flour or wood. After being carried on a chip or the like, it can be added as a harmful compound decomposing agent to contaminated incineration fly ash or contaminated soil in the form of a culture solution containing the wood flour or wood chip or the like.

In addition, as the microorganism activating substance, other certain organic compounds and metal ions (iron ions, magnesium ions, copper ions, zinc ions, etc.) can also be used. Examples of the organic compound that can be used as a microorganism activating substance include veratryl alcohol and a surfactant. Examples of the surfactant include a nonionic surfactant, for example, polyoxyethylene sorbitan fatty acid ester. As the polyoxyethylene sorbitan fatty acid ester, those commercially available as Tween-based surfactants can be used, and Tween 80 is preferable. The specific organic compound or metal ion similarly enhances the ability to produce harmful compound-decomposing substances (for example, enzymes) derived from the microorganism, and improves the activity of decomposing harmful compounds. In the present invention, at the time of culturing the microorganism, by maintaining these compounds in a medium at an appropriate concentration, a culture solution having enhanced activity for decomposing harmful compounds can be prepared and used as a decomposing agent.

Alternatively, in the above-mentioned culture, a nutrient material capable of adjusting pH (to be described in detail later), for example, an appropriate p
By culturing with the addition of soil or compost for H buffer, a culture solution having a pH buffering ability can be used as the harmful compound decomposing agent of the present invention. As will be described later, in the above-mentioned culture, without adding a woody substance, only a nutrient material having a pH adjusting ability is added to the medium for culturing, and the present invention is performed in the form of a culture solution having a buffering ability. Harmful compound decomposers can also be prepared.

Microorganisms having the ability to decompose dioxins, such as white rot fungi, secrete enzymes outside the body of the sonozoa [Barr,
D. P. And Aust, S .; D. , Environ. S
ci. Technol. 28 (2), 78A-87A
(1994)], the liquid phase portion of the culture solution is rich in enzymes involved in the degradation of dioxins such as lignin peroxidase and manganese peroxidase. Therefore, the liquid phase portion immediately after the harmful compound decomposing agent is applied to the contaminated material to be treated, that is, when the harmful compound decomposing microorganisms are not widely dispersed and proliferated throughout the system of the contaminated material to be treated. Plays a role in promoting the decomposition of harmful compounds. Also, only this liquid phase portion can be used as a harmful compound decomposing agent.

In the present invention, for example, Morg
[Morgan, P. et al. Et al., Soil. Bi
ol. Biochem. , 25 (2), 279-287.
(1993)], the harmful compound-degrading microorganisms are cultured on an agar medium, and the agar is cut into an appropriate size while the harmful compound-degrading microorganisms are still supported, and the harmful compound-degrading microorganism-carrying agar fragments are obtained. In addition, an activating substance such as a wood substance can be separately added.

Wood flour and straw are known as substances that induce the decomposition of chemical substances by microorganisms. For example, PC bacterium, which is a kind of white rot fungus, and Becandera adasta (Bj
In the decomposition of styrene by Ekandera adusta), it has been reported that the addition of spruce wood powder significantly improved the decomposition activity [Braun-
Lulemann, A .; Et al., Appl. Micro
biol. Biotechnol. , 47 (2), 15
0-155 (1997)]. In addition, 3,4 by PC bacteria
It has been reported that the addition of straw and wood chips similarly improved the decomposition of dichloroaniline [Morgan, P. et al. Et al., Soil. Bio
l. Biochem. , 25 (2), 279-287.
(1993)].

Veratryl alcohol, Tween 80 as a surfactant, iron ion, magnesium ion, copper ion, zinc ion and the like preferentially enhance the production ability of lignin peroxidase and the like secreted by the microorganism. Is known to improve its activity [Nakamura et al. , J. et al. Chem
ical Engineer. Jpn. , 30 (1),
1-6 (1997), Haapala et al. ,
Appl. Microbiol. Biotechno
l. , 40, 494-498 (1993)]. And
It has been suggested that lignin peroxidase and the like are deeply involved in the decomposition of compounds such as dioxins [Tachibana et al., Pulp and Paper Technical Association, 51 (11), 1759-176].
8 (1997)]. However, it is not clear from these documents whether the addition of the substance promotes the decomposition of compounds such as dioxins.

As described above, the addition of wood flour or straw improves the decomposability of white rot fungi to compounds such as styrene and 3,4-dichloroaniline, and the addition of certain substances. It is known that the lignin peroxidase activity of the microorganism is improved. On the other hand, the present inventors have developed a substance that improves the dioxin decomposition activity of microorganisms having dioxin decomposability such as white rot fungi and the like, that is, the white rot fungi and the like are carried on a woody substance that is a microorganism activating substance. The prepared harmful compound decomposing agent according to the present invention was used, or the liquid phase portion containing the enzyme group secreted out of the cells from the harmful compound degrading microorganisms carried on the woody material was carried on the woody material. Using a harmful compound decomposer containing the harmful compound decomposing microorganism, or using a decomposer having enhanced harmful compound decomposing activity by adding the activating substance, or using the harmful compound degrading microorganism together with the microbial activity Of harmful compounds in solids, which have been rarely applied in the past, ie, contaminated incinerated ash and contaminated soil, by adding Also, it was found that it is possible to reliably improve the degradability than using hazardous compounds decomposable microorganism alone.

As described above, the pH of the leachate from incinerated ash or the like is generally high, and the environment is often unsuitable for the growth of harmful compound-decomposing microorganisms. When treating such incinerated ash, not only water but also a nutrient material having a pH adjusting ability (for example, soil or compost having a pH adjusting ability) is added to the incinerated ash to be treated in an appropriate amount and mixed. System suitable for the growth of harmful compound-degrading microorganisms
H state. Examples of the pH-adjusting nutrient include soil for buffering, compost obtained by composting kitchen waste, and the like, and these can be used alone or in combination. In general, soil has a large amount of carboxyl groups and phenol groups in its humus, and has a pH-dependent negative charge (weak acid group) such as the destruction valency of clay minerals. That is, the buffer capacity is shown [Yasuo Takai, Hiroshi Miyoshi, "Soil Communication", Asakura Shoten (1977)].

Compost is similar to humus in the soil and has a large amount of carboxyl groups and phenol groups, so that it also has a buffering capacity. Therefore, by adding soil or compost to the reaction system,
The growth environment of the harmful compound-degrading microorganism can be maintained at an appropriate pH condition. Specifically, the treatment is performed while maintaining the pH of the contaminated material to be treated in the reactor at 5 to 10. The addition of the buffer soil also has an effect of supplying nutrients necessary for the growth of harmful compound-degrading microorganisms.

As the buffer soil that can be used in the present invention, the incineration ash and the like mixed together are often highly alkaline, so that the pH conditions under which harmful compound-degrading microorganisms grow (weakly alkaline or more) are used. Use of a soil having an effect of pulling back, specifically, volcanic ash soil or the like which is acidic in a natural state is preferable, but is not limited to this as long as it shows an appropriate buffering capacity. Alkaline soil may be used, or it may be present in the natural state, or may be soil which is present in the natural state artificially modified with an agent or the like, and is not limited to its existing state. . In addition, as for the compost that can be used in the present invention, the raw materials are kitchen garbage, urine sludge,
Sewage sludge, feces storage, etc. may be used alone or in a mixture thereof. The material is not limited by the composition of the raw material or the composition of the compost as long as it has an appropriate buffer capacity.

When the method of the present invention is carried out, that is, the harmful compound decomposing agent according to the present invention is added to the contaminated material to be treated, or the harmful compound degrading microorganism and the microorganism activating substance are separately treated and contaminated. When adding to the material, the environment of the material to be treated is set to the growth condition of the harmful compound-degrading microorganism to be used, preferably the optimum growth condition. That is, an appropriate amount of water is added to contaminated materials such as incineration ash to be treated, and the treatment system is brought into a water state suitable for growth of harmful compound-decomposing microorganisms. Specifically, the water content is 25 to 70% by weight, preferably 45 to 60% by weight, based on the entire processing system. The treatment system is appropriately ventilated to supply oxygen necessary for the growth of harmful compound-degrading microorganisms. Specifically, the treatment is performed while maintaining the oxygen concentration at 15 to 21 mol%, preferably 18 to 20 mol%, based on the entire processing system. The oxygen concentration can be adjusted, for example, by monitoring the oxygen concentration in the exhaust gas with a concentration meter. The temperature in the treatment system during the culture treatment is 10
C. to 40.degree. C., but is not limited to this, and is usually around room temperature (i.e., around 25.degree. C.).

The method of the present invention can be carried out using any reaction vessel. For example, when the contaminated material to be treated is a small amount such as incineration ash, the incineration ash to be treated can be treated in a plastic case or the like with a lid. Also, when treating a large amount of contaminated materials, such as a large amount of incineration ash generated in a relatively large incineration facility,
It is possible to use a fermenter of a compost production system or a treatment tank obtained by improving the fermenter. When a relatively wide range of soil is contaminated with a harmful compound (particularly dioxin), the harmful compound decomposing agent according to the present invention is directly applied to the surface or surface portion of the contaminated soil (for example, spraying). Alternatively, the harmful compound-degrading microorganism and the activating substance are separately applied (eg, sprayed),
Harmful compounds can be degraded.

The inventor has found an apparatus suitable for carrying out the method of the present invention. That is, the harmful compound contaminant processing apparatus is a reactor, a means for stirring the harmful compound contaminant in the reactor, a means for introducing air into the reactor, a temperature control means, a pH control means, Water content control means. The reactor can be any shape as long as it can store the contaminated material to be treated. Although an open system or a closed system may be used, it is preferable to have a lid capable of sealing the inside, since it is easy to maintain the temperature, the amount of water, and the like constant. The means for agitating the contaminated material in the reactor may be any means capable of agitating the contaminated material in the reactor, such as any power (eg, electric motor, fire engine, or manual) Can be a rotatable stirring blade or the like. The means for introducing air into the reactor can be a conventional device used for introducing air into a closed space, for example, a blower. The temperature control means is means for heating (or cooling) the contaminated material in the reactor, and may be, for example, an electric heating device. The temperature control means is used in combination with a temperature measuring means for monitoring the temperature of the contaminated material to be treated. The pH control means is used in combination with a pH measuring means for monitoring the pH of the contaminated material to be treated, and supplies a pH adjusting material when necessary. The water content control means is used in combination with a water content measurement means for monitoring the water content of the contaminated material to be treated, and supplies water when necessary.

[0030] In a preferred embodiment of the apparatus of the present invention, the reactor is a closed type, and an insertion port (and an insertion lid) for the material to be treated and an outlet (and an outlet lid) for the processed material are horizontally arranged. It is a horizontal type. In addition, when mixing contaminated materials such as incinerated fly ash and harmful compound decomposers, or when water is added to adjust the amount of water, stirring is performed so that the state of the system to be treated is uniform. A rotating shaft having stirring blades for horizontal rotation is disposed across the entire inside of the reactor, and is powered by a motor. Then, the air sent from the blower is supplied into the system through one or a plurality of vents provided in the lower part of the reactor, and the oxygen concentration required for the growth of the harmful compound-decomposing microorganism is maintained. Ventilation into the system is performed about once a day. At this time, the stirring blade is rotated at an appropriate speed so that oxygen is uniformly distributed to the contaminated material system to be treated. A heating means (for example, a heater) for heating by supplying electricity is installed around the reactor, and when the activity of the harmful compound-decomposing microorganisms decreases due to low temperature such as in winter. Is appropriately heated in the reactor. And means for supplying water when the water content falls below the appropriate range, and when the pH is out of the appropriate range, add soil or compost to restore it, or Means for adding neutralizing agents and means for monitoring these growth conditions are also provided.

In the present specification, “incineration ash” includes incineration fly ash, incineration main ash, etc., and includes incineration facilities (for example, small incinerators, holes dug in soil for incineration, waste incineration facilities, etc.). ) And ash generated in the incineration facility and transported to the final disposal site.

[0032]

EXAMPLES The present invention will be described below in more detail with reference to examples, but these examples do not limit the scope of the present invention.

Example 1 (1) Preparation of Degrading Agent for Harmful Compounds Basal solution of Kirk et al. [Arch. Microb
iol. , 117, 277 (1978)], and a medium whose pH was adjusted to 4.5 after addition of 20 mM ammonium tartrate was used as a liquid medium for culture. After the liquid medium was sterilized in an autoclave, 100 ml of the liquid medium was dispensed into a 300 ml Erlenmeyer flask, 50 g of beech wood flour was added to the dispensed medium, and the V2 strain cultured on malt-agar medium was added. [Tachibana et al., Pulp and Paper Technical Association Magazine, 50 (1
2), 122-131 (1996)].
The cells were cultured at 5 ° C. for 7 days. During this stationary culture,
Oxygen was bubbled into the reaction once a day. The wood flour-containing liquid culture solution thus obtained is referred to as a harmful compound decomposer (A). Also, instead of the beech wood flour, Tw
een80 (0.5%), veratryl alcohol (1m
M), iron sulfate (5 mM), magnesium sulfate (5 m
M), copper sulfate (5 mM), or zinc sulfate (5 mM) was separately added to the medium, and the liquid cultures obtained by culturing in the same manner were sequentially added to the harmful compound decomposing agent (B) and the harmful compound decomposing agent (B). A compound decomposer (C), a harmful compound decomposer (D), a harmful compound decomposer (E), a harmful compound decomposer (F), and a harmful compound decomposer (G). Each of these harmful compound decomposing agents (A) to (G) was subjected to a dioxin decomposition treatment.

(2) Decomposition of 2,7-dibenzo-para-dioxin in incineration fly ash 100 g of incineration fly ash in a waste incineration facility and volcanic ash surface soil [surface layer of volcanic ash soil in Kagoshima Prefecture (0 to 15 c
m)] in a plastic lidded container and mixed, and then 1% Tween 80
2,7-dibenzo-para-dioxin (hereinafter, referred to as
30 ml of a mixed solution of N, N-dimethylformamide / water (concentration: 1 ppm) of 2,7-DCDD) was added and mixed. The 2,7-D used in this experiment
CDD is published in the literature [Tachibana et al., Paper and Pulp Technical Journal, 50 (12),
122-131 (1996)]. Distilled water was added to the mixture so that the total water content was 70%, and then the above Example 1 (1) was used.
Of the harmful compound decomposer (A) (containing 20 g of beech wood flour) prepared in the above, stirred, and cultured at 25 ° C. for 30 days.

(3) Control Test and Reference Experiment In the control experiment, the harmful compound decomposing agent (A) prepared in Example 1 (1) by the operation of Example 1 (2) was used.
Instead of using a cell, a V2 strain cultured on a malt-agar medium in a commercially available plastic petri dish (diameter: 10 cm) and cut into about 5 mm square while being supported on the agar medium is used. Otherwise, the operation of Example 1 (2) was repeated. Further, as a reference experiment, an experiment in which incineration fly ash is treated with the decomposing agent (A) prepared in Example 1 (1) without mixing the volcanic ash surface soil in the operation of Example 1 (2). I also went.

(4) Evaluation Periodically, a sample is taken out from the material to be treated during the culture treatment, 2,7-DCDD and metabolites are soxhlet extracted with toluene from the sample, and the extract is cleaned up with an alumina column. After that, the metabolite was trimethylsilylated with N, O-bis-trimethylsilylamide, and then analyzed by gas chromatography. Table 1 shows that 2,7-
The change over time (days) of the residual ratio (%) of DCDD is shown.

<< Table 1 >> 2,7-DCDD Residual Rate (%) The present invention control test Reference test treatment days Fly ash + soil + decomposer fly ash + soil + bacteria only fly ash + decomposer 0 100 100 100 15 48 82 97 30 39 61 96

As is clear from Table 1, on the 30th day of the culture treatment, the residual ratio of 2,7-DCDD of the system (control test) to which only the bacterium was added without using the decomposing agent of the present invention was 61.
% Of the system in which soil was not mixed (reference test), and the harmful compound decomposing agent (A) according to the present invention (A) despite the fact that the 2,7-DCDD residual ratio was 96% and decomposition did not proceed so much. In the system to which was added, the 2,7-DCDD residual ratio was 39%, indicating that the decomposition was well advanced.
Therefore, in the biodegradation of 2,7-DCDD, the addition of the harmful compound decomposer according to the present invention is more effective than the use of the microorganism alone. In addition, it was shown that mixing of soil with incinerated fly ash was effective for improving the growth environment of harmful compound-degrading microorganisms, and promoted the growth of degrading microorganisms.

[0038]

Example 2 (1) 2,7-dibenzo-para- in soil
Decomposition of dioxin Natural soil collected from Ehime University experimental forest (water content 70
%) 4 kg in a container with a plastic lid (dimensions: 40 × 3
0 × 15 cm) and 2,7-DCDD in DMF / water-solution containing 1% Tween 80 (concentration 1 ppm)
300 ml was evenly sprayed on the surface of the soil. 200 ml of the harmful compound decomposers (A) to (G) prepared in Example 1 (1) were separately added to the surface of the contaminated soil thus prepared, and the mixture was gently mixed with the surface of the soil.
Culture treatment was performed at 25 ° C. for 30 days.

(2) Control test In the control experiment, a commercially available plastic petri dish was used instead of the harmful compound decomposing agent prepared in Example 1 (1) by the operation of Example 2 (1). (Diameter 1
0 cm) was used. The V2 strain cultured on a malt-agar medium at 0 cm) was cut into pieces of about 5 mm square while being supported on the agar medium. Operation was repeated. (3) Evaluation The analysis of 2,7-DCDD in the soil was performed in the same manner as in Example 1 (4). Table 2 shows the change over time (days) of the residual ratio (%) of 2,7-DCDD in soil when the initial concentration is 100%.

<< Table 2 >> 2,7-DCDD Residual Rate (%) Decomposing Agent of the Present Invention Control Test Treatment Days ABCDEFG Bacteria Only 0 100 100 100 100 100 100 100 100 15 51 65 53 62 70 71 68 74 30 35 48 38 50 52 49 53 57

As can be seen from Table 2, in the system to which the harmful compound decomposing agent (A) according to the present invention was added, the 2,7-DCDD residual ratio was reduced to 51% on the 15th day of culture, and finally, On the other hand, the 2,7-DCDD residual ratio was reduced to 35% in the day, whereas the control test to which only the bacterium was added showed that the 2,7-DCDD residual ratio was 74% on the 15th day of culture, and even after 30 days in the culture. 2,7-DC
The DD residual rate has decreased only to 57%. Similarly, the decomposition agents (B) to (G) were 2,7 more than the control test.
-The DCDD residual rate has decreased. Therefore, it was shown that the use of the harmful compound-decomposing agent of the present invention was more effective in decomposing 2,7-DCDD in contaminated soil than the harmful compound-degrading microorganism alone.

[0042]

Example 3 (1) Apparatus for treating harmful compound contaminated materials In Example 3, the following apparatus was manufactured and used. The reactor is a closed horizontal type, and a rotating shaft having stirring blades is horizontally arranged in the reactor, and the rotating shaft is supplied with power by a motor. A vent is provided at the bottom of the reactor, and air is sent from the blower. Having a heater around the reactor,
Moisture content measurement unit and water supply unit linked to it, pH
It has a measuring section and a pH adjusting material supply section associated therewith.

(2) Decomposition of 2,7-dibenzo-para-dioxin in incineration fly ash 5 kg of incineration fly ash in a waste treatment facility and volcanic ash surface soil [surface layer of volcanic ash soil in Kagoshima Prefecture (0 to 15 c
m)] 5 kg (dry weight) and Tween 80
1.5 liters of a mixed solution (concentration 1 ppm) of 2,7-DCDD containing N, N-dimethylformamide / water (1%) containing 1.5% (1%) was placed in the reactor of the processing apparatus manufactured in Example 3 (1). And mixed. Thereafter, distilled water was added so that the entire water content of the material system to be treated was 70%, and then 2 liters of the harmful compound decomposer (A) prepared by the method of Example 1 (1) (beech wood flour) (Containing 1 kg), and the mixture was stirred and cultured for 30 days. Reactor temperature 2
The temperature was adjusted to 5 ° C., the air was ventilated once a day, and the operation was performed under such conditions that the pH of the treatment system in the reactor was maintained at around 6.0. Analysis of 2,7-DCDD in the treatment system was performed in the same manner as in Example 1 (4). Table 3 shows the initial concentration of 10
The change with time of the residual ratio of 2,7-DCDD in the mixture when 0% is set is shown.

[0044]

As can be seen from Table 3, the number of culture treatment days was 1
In 5 days, 2,7-DCDD residual rate decreased to 58%,
In a day, the residual ratio of 2,7-DCDD was reduced to 31%, and the degradation by harmful compound-degrading microorganisms was successfully advanced. Therefore, it was shown that the use of the apparatus of the present invention enables the decomposition treatment of dioxin in incineration fly ash while maintaining a favorable growth environment for harmful compound-degrading microorganisms.

[0046]

As described above, the use of the harmful compound decomposing agent of the present invention containing a harmful compound decomposing microorganism and a microbial activator enables the decomposition of dioxin in incinerated fly ash and the like by a complete combustion method. It does not require expensive treatment equipment such as conventional techniques, can be performed easily and inexpensively, and can reduce harmful compounds more effectively than when harmful compound-degrading microorganisms are used alone. is there. Also,
Due to the presence of incineration ash, the pH is high, and even under severe environmental conditions for the growth of harmful compound-degrading microorganisms,
By using a nutrient material having a regulating ability (for example, soil or compost) simultaneously with or separately from a woody substance, it is possible to treat the microorganism under the conditions suitable for degrading harmful compounds, making it easy, inexpensive, and effective. Harmful compounds can be decomposed and / or reduced.

Further, by performing treatment using the apparatus of the present invention, it is possible to secure and / or maintain optimal growth conditions for harmful compound-degrading microorganisms even when handling a large amount of contaminated materials, It is possible to maximize the effectiveness of adding an agent, soil or compost. And even when the harmful compound is distributed in a relatively wide range at a relatively low concentration, such as soil contaminated with the harmful compound, together with the harmful compound decomposing agent of the present invention, or a harmful compound decomposing microorganism such as white rot fungus. By using the method of separately adding woody substances, it is possible to effectively detoxify harmful compounds by harmful compound-degrading microorganisms.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Sachiro Tachibana 3-5-7 Tarumi, Matsuyama-shi, Ehime Pref. 1-2 1-2 Nihon Kokan Co., Ltd. (72) Inventor Kazuyoshi Suzuki 1-2-1, Marunouchi Chiyoda-ku, Tokyo 1-2-2 Nihon Kokan Co., Ltd. (72) Kunio Miyazawa 1-chome Marunouchi, Chiyoda-ku, Tokyo No. 1-2 Nippon Kokan Co., Ltd. (72) Inventor Takaaki Kondo 1-2-1, Marunouchi, Chiyoda-ku, Tokyo F-term (in reference) 4B065 BB06 BB09 BB26 BB34 BB38 BC42 CA56 4D004 AA36 AA41 AB07 CA18 CC05 CC08 CC11 CC15 CC20 DA02 DA03 DA06 DA09 DA20

Claims (8)

[Claims] 1. A harmful compound decomposing agent comprising: a microorganism having the ability to degrade harmful compounds; and an activator of the microorganism. 2. The harmful compound decomposer according to claim 1, wherein the harmful compound is dioxin. 3. The harmful compound decomposer according to claim 1, wherein the activating substance is a woody substance. 4. The harmful compound decomposer according to claim 1, wherein the activating substance is a surfactant, veratryl alcohol, or a metal ion. 5. The harmful compound decomposer according to claim 4, wherein the metal ion is an iron ion, a magnesium ion, a copper ion, or a zinc ion. 6. The harmful compound decomposer according to claim 1, wherein the activating substance is a nutritional material having a pH adjusting ability. 7. A method for treating a harmful compound-contaminated material, comprising treating a material contaminated with a harmful compound in the presence of a microorganism having the ability to degrade harmful compounds and an activator of the microorganism. 8. A reactor, means for stirring harmful compound contaminated materials in the reactor, means for introducing air into the reactor, temperature control means, pH control means, water content control means, An apparatus for treating harmful compound contaminated materials, comprising: