WO2011148509A1 - Agent and method for purifying medium contaminated with organic chlorine compound - Google Patents

Abstract

An agent and a method for purifying a medium contaminated with an organic chlorine compound are provided with which a medium, e.g., soil, groundwater, or bottom sediment, that has been contaminated with an organic chlorine compound can be purified in a short period and rapidly restored to the original environment, and which impose little burden on the environment. An anaerobic ingredient system to be used under anaerobic conditions which comprises solid milk, an acetic acid salt, Casamino acid, soybean oil, a yeast extract, cyanocobalamin, or a magnesium salt and an aerobic ingredient system to be used under aerobic conditions which comprises a phosphoric acid salt, an ammonium salt, a nitric acid salt, or a potassium, sodium, calcium, or iron compound are used, and the conditions are changed from anaerobic conditions to aerobic conditions. Thus, mono- and dichloro compounds are rapidly decomposed.

Description

Purification agent and purification method for organic chlorine compound contaminated media

The present invention relates to a purification agent and a purification method for an organic chlorine compound-contaminated medium for purifying a medium contaminated with an organic chlorine compound.

Organochlorine compounds typified by tetrachloroethylene and trichlorethylene are hydrocarbons or substances obtained by adding chlorine to carbon. This organochlorine compound has been artificially produced and used in the past as a solvent in many industrial fields for degreasing and cleaning. However, its harmfulness to living organisms, environmental degradability, and accumulation are problematic and are now recognized as harmful substances worldwide.

In Japan, environmental standards for soil and groundwater are set for 10 substances such as tetrachlorethylene and trichlorethylene. These cause underground soil and groundwater contamination due to inappropriate use and storage methods.

As a means for purifying an environment polluted by harmful chemical substances, a method of purifying using microorganisms (bioremediation) has attracted attention. This method has great advantages in that power and equipment are low in cost and easy in-situ purification as compared with conventional physical and chemical treatment methods.

This bioremediation can be purified by adding foreign microorganisms with high ability to decompose pollutants and by supplying nutrients to the microorganisms for growth or by increasing metabolism to pollutants. It is roughly divided into biostimulation.

Regarding bioaugmentation using foreign microorganisms, practical application is currently under consideration, taking into account mutation of microorganisms, diffusion outside the region, and the like. Biostimulation, on the other hand, can be used in in-situ purification work at many contaminated sites because it can utilize native microorganisms and only add nutrients and other materials to the target environment. It has become like this.

By the way, it is known that tetrachlorethylene (PCE), trichlorethylene (TCE) and the like having a large number of chlorine among organic chlorine compounds are sequentially decomposed by reductive dechlorination by anaerobic microorganisms. For the bioremediation of conventional organochlorine compounds, the method using anaerobic microorganisms is the mainstream.

In order to solve the problem of the conventional bioremediation agent for organic chlorine compounds, the present inventors have made soil, groundwater or sediment soil contaminated in Patent Document 1 and Patent Document 2 regarding purification of organic chlorine compounds by anaerobic microorganisms. Additives for use in repairing the skin are disclosed. These additives have high water-solubility of materials that serve as nutrients and energy sources, and are highly biodegradable, so that they easily diffuse in the soil, and dissolved oxygen (DO: Dissolved Oxygen) also binds oxygen ( The process of creating an anaerobic state in which NO) of NOX- does not exist and decomposing and purifying the organochlorine compound proceeds rapidly.

As a result, the interval between the wells for injecting the purifying agent can be widened, and the effect can be exerted over a wide range by injecting from a small number of points. In addition, since the contaminated medium quickly forms and maintains an anaerobic state after the injection of the cleaning agent, it is possible to decompose and purify organochlorine compounds before they are affected by interfering substances, thereby reducing the amount of work in purification. It became possible to achieve a shortening of the purification period. Furthermore, since it is selected from components having high biodegradability in the environment, the purification agent becomes carbon dioxide and water after the purification is completed, and does not remain on the site.

JP 2005-185870 A JP 2005-288276 A

In conventional bioremediation of organochlorine compounds, for example, when biostimulation is applied to in-situ purification, low chlorine, especially organochlorine compounds of 2 chlorines or less are obtained by dechlorination of anaerobic microorganisms. When purifying by detoxification alone, new problems have arisen especially when the concentration of contamination is high or when there are time restrictions on the construction.

That is, as described above, dechlorination proceeds when an organic chlorine compound is rendered harmless by an anaerobic microorganism. On the way, organic chlorine compounds with low chlorine, especially 2 chlorines or less, for example, substances for which environmental standards are specified such as cis-1,2-dichloroethylene, 1,2-dichloroethane, dichloromethane, and others, 1,1-dichloroethane 1,2-dichloropropane and the like are produced.

These generated organic chlorine compounds of 2 chlorines or less tend to be dechlorinated by anaerobic microorganisms more slowly than organic chlorine compounds of 3 chlorines or more.
In addition, in places where these low chlorine organochlorine compounds are industrially used, they themselves may become a pollutant and contaminate the geology. Furthermore, especially in places where the concentration of the organic chlorine compound is high, accumulation of the organic chlorine compound of 2 chlorine or less generated by dechlorination by an anaerobic microorganism may proceed.

On the other hand, it is known that contamination with organochlorine compounds of 2 chlorines or less is rendered harmless in bioremediation using aerobic microorganisms.

The object of the present invention is to clean up organic media such as soil, groundwater and sediments contaminated with organochlorine compounds in a short period of time in a short period of time. An object of the present invention is to provide a purification agent and a purification method for a chlorine compound contamination medium.

The purifying agent of the present invention is characterized by decomposing a compound in which two or less chlorines are bonded while maintaining an aerobic state by injecting an aerobic component system into a medium with water in which a specific component gas is dissolved. And

In addition, the purifying agent of the present invention decomposes a compound in which three or more chlorines are bonded by injecting the medium into an anaerobic state by injecting into a medium contaminated with chlorine or a compound having a nitro group bonded thereto, so that two or less chlorines are present. It is characterized by comprising an anaerobic component system which is a compound to which is bonded and an aerobic component system which decomposes a compound to which two or less chlorines are bonded under an aerobic condition.

By injecting the aerobic component system into the medium with water in which a specific component gas is dissolved, it is possible to maintain the aerobic state and decompose a compound in which two or less chlorines are bonded.
The specific component gas may be one or more of methane, ethane, propane, and butane and oxygen.

It is preferable that the anaerobic component system is composed of one or more of carbon component, organic acid, organic acid salt, protein, vegetable oil, surfactant, vitamin and mineral.

The carbon component can be one or more of whey, lactose, sucrose, glucose, molasses, starch, soy milk, polylactic acid, and xanthan gum.

Organic acids and their salts can be one or more of acetic acid, propionic acid, lactic acid, butyric acid and their salts.

The protein can be one or more of yeast extract, peptone, casamino acid, malt extract, beef extract, meat extract, chicken extract, polypeptone, and gelatin.

The vegetable oil may be one or more of peanut oil, palm oil, safflower oil, sunflower oil, rice bran oil, soybean oil, corn oil, rapeseed oil, linseed oil, cottonseed oil, olive oil, tung oil, and grape oil.

As the surfactant, stearoyl lactic acid, sucrose fatty acid ester, dihexyl sulfo succinic acid, alkyldiphenyl oxide disulfonic acid, polyethylene glycol dodecyl ether, lauroyl lactic acid, nonylphenol ethoxylate, polyoxyethylene sorbitan monooleate, dioctyl sodium sulfosuccinate, It can be one or more of polyoxylene-para-isooctylphenone and salts thereof.

The vitamins may be three or more of cyanocobalamin, hydroxycobalamin, methylcobalamin, biotin, folic acid, thiamine, riboflavin, ascorbic acid, pantothenic acid, ergocalciferol, phenoquinone, and β-glucan.

The mineral can be one or more of magnesium, iron, cobalt, zinc and their salts.

The aerobic component system may be one or more of phosphate, ammonium salt, nitrate, potassium, sodium, calcium, and iron compound.

The medium purification method of the present invention is characterized by comprising the steps of maintaining an anaerobic state by an anaerobic component system using the purifier of the present invention, and then switching to an aerobic state by an aerobic component system. To do. *

An anaerobic component system is dissolved 10 to 500 times in water and injected naturally into the target medium, or in a formation with a low water permeability, it is injected by pressure injection to obtain a pH of 6.5 to 8.5 and an ORP value. It is possible to maintain 0 mV or less, DO value of 0.5 mg / L or less, and TOC value of 50 mg / L or more.

One or more of phosphate, ammonium salt, nitrate, potassium, sodium, calcium, iron compound to be 10-500 times in water in which one or more of methane, ethane, propane, butane and oxygen are dissolved Naturally injected into the target medium by dissolving the gas component system, or in the formation with a low water permeability coefficient, by injection by pressure injection, pH 6.5 to 8.5, ORP value of 0 mV or more, DO value The electric conductivity can be maintained at 2 mg / L or more and 50 μs / cm or more.

Further, the medium purification method of the present invention comprises a step of dropping the purification agent of the present invention to maintain an anaerobic state by an anaerobic component system and decomposing three or more chlorine-bonded compounds, and methane, ethane after a predetermined period of time. And a step of injecting water in which a specific component gas composed of one or more of propane and butane and oxygen is injected into the medium to switch to an aerobic state. *

A target medium in which the purifying agent is dropped and the anaerobic component system is maintained in an anaerobic state to decompose three or more chlorine-bonded compounds by dissolving the purifying agent in water 10 to 500 times. In natural formation or in formations with low hydraulic conductivity, by applying pressure injection, the target medium has a pH of 6.5 to 8.5, an ORP value of 0 mV or less, and a DO value of 0.5 mg / L or less. , TOC value can be managed to 50 mg / L or more.

Naturally injected water containing a specific component gas consisting of one or more of methane, ethane, propane, and butane and oxygen into the medium, or in the formation with low hydraulic conductivity, it is aerobic by injecting by pressurized injection The step of switching may be controlled to pH 6.5 to 8.5, the ORP value is 0 mV or more, the DO value is 2 mg / L or more, and the electrical conductivity is 50 μs / cm or more.
Moreover, about a poorly water permeable layer (low water permeability layer), purification efficiency can be improved by pressure-injecting at least one of an anaerobic component system and an aerobic component system.

[Action]
Using the above-described purification agent of the present invention, contaminants can be quickly purified by microorganisms. In particular, by supplying the medium with water in which at least one of oxygen and methane, ethane, ethylene, propane, and butane is dissolved, the microorganism is brought into contact with microorganisms present in the medium, and the microorganisms supply these substances as nutrients. Alternatively, it can be used as a respiration source to proliferate and activate to quickly detoxify organochlorine compounds having 2 or less chlorine atoms. As a result, it is possible to quickly and inexpensively purify a medium contaminated with an organic chlorine compound having a chlorine number of 2 or less, which has taken a long time.

Further, by supplying water, in which at least one of oxygen and methane, ethane, ethylene, propane, and butane is dissolved, the dissolved oxygen concentration in the aqueous phase in the target medium is 2 mg / L or more, Concentration and type of target pollution by adding one or more substances of methane, ethylene, ethane, propane, or butane to an aerobic state with an oxidation-reduction potential (ORP) value of 0 mV or more Depending on the conditions, various application modes are possible, and the application range can be widened.

In the purification agent and purification method of the present invention described above, when the pollutant is an organochlorine compound of 3 chlorines or more, the dechlorination proceeds by anaerobic microorganisms in an anaerobic state until the substance becomes 2 chlorines or less. By supplying oxygen, detoxification of contamination can be rapidly advanced by an aerobic microorganism as an aerobic state.
In this way, by taking into account the action of the various microorganisms that make up the group of microorganisms involved in the process of decomposing compounds bound with chlorine or nitro groups, multiple types of substances with different properties can be supplied as purification agents. Thus, it is possible to achieve a bioremediation method that is efficient and does not easily leave harmful substances.

In addition, after supplying the cleaning medium comprising an anaerobic component system and an aerobic component system to the target medium, oxygen or even one or more of methane, ethane, ethylene, propane, and butane was dissolved at the required time. Water can be supplied to the target medium.
In addition, after supplying the anaerobic component system to the target medium, oxygen and even water in which at least one of methane, ethane, ethylene, propane, butane is dissolved and the aerobic component system are targeted. You may supply to a medium simultaneously.
Furthermore, after supplying a purifying agent comprising an anaerobic component system and an aerobic component system to the target medium, oxygen or even one or more of methane, ethane, ethylene, propane and butane was dissolved at the required time. Water and the aerobic component system to be replenished may be simultaneously supplied to the target medium.

According to the purification agent and the purification method of the present invention, when organic chlorine compounds in a medium contaminated with organic chlorine compounds such as soil, groundwater, and sediment are purified in situ, the load on the environment is reduced by indigenous microorganisms. This makes it possible to quickly restore the environment before use in a short period of time.

It is a graph which shows the 1st test result performed by adding tetrachloroethylene so that it might become 1 mg / L in Example 2 of this invention. It is a graph which shows the 1st test result performed by adding tetrachloroethylene so that it might be set to 100 mg / L in Example 2 of this invention. It is a graph which shows the 2nd test result performed by adding tetrachlorethylene so that it might become 1 mg / L in Example 2 of this invention. It is a graph which shows the 2nd test result performed by adding tetrachlorethylene so that it might be set to 100 mg / L in Example 2 of this invention. It is a graph which shows the 2nd test result performed by adding trichloroethane so that it might become 1 mg / L in Example 2 of this invention. It is a graph which shows the 2nd test result performed by adding trichloroethane so that it might be set to 50 mg / L in Example 2 of this invention. It is a graph which shows the 3rd test result performed by adding tetrachlorethylene so that it might become 1 mg / L in Example 2 of this invention. It is a graph which shows the 3rd test result performed by adding tetrachloroethylene so that it might be set to 100 mg / L in Example 2 of this invention. It is a graph which shows the 3rd test result performed by adding trichloroethane so that it might become 1 mg / L in Example 2 of this invention. It is a graph which shows the 3rd test result performed by adding trichloroethane so that it might be set to 50 mg / L in Example 2 of this invention. It is a graph which shows the 4th test result performed by adding tetrachloroethylene so that it might become 1 mg / L in Example 2 of this invention. It is a graph which shows the 4th test result performed by adding tetrachloroethylene so that it might be set to 100 mg / L in Example 2 of this invention. It is a graph which shows the 4th test result performed by adding trichloroethane so that it might become 1 mg / L in Example 2 of this invention. It is a graph which shows the 4th test result performed by adding trichloroethane so that it might be set to 50 mg / L in Example 2 of this invention. It is a graph which shows the 5th test result performed by adding tetrachloroethylene so that it might become 1 mg / L in Example 2 of this invention. It is a graph which shows the 5th test result performed by adding tetrachloroethylene so that it might be set to 100 mg / L in Example 2 of this invention. It is a graph which shows the 5th test result done by adding trichloroethane so that it might become 1 mg / L in Example 2 of this invention. It is a graph which shows the 5th test result conducted by adding trichloroethane so that it might be set to 50 mg / L in Example 2 of this invention. It is a graph which shows the 5th test result performed by adding carbon tetrachloride so that it might become 1 mg / L in Example 2 of this invention. It is a graph which shows the result of the switching test which added the tetrachlorethylene in Example 3 of this invention so that it might be set to 100 mg / L, and performed the VOC decomposition | disassembly test by switching from anaerobic conditions to aerobic conditions. It is a graph which shows the result of the switching test which added the trichloroethane in Example 3 of this invention so that it might be set to 50 mg / L, and performed the VOC decomposition | disassembly test by switching from anaerobic conditions to aerobic conditions. In Example 3 of the present invention, tetrachlorethylene was added to 100 mg / L, and VOC decomposition was performed by switching from anaerobic to aerobic conditions when anaerobic and aerobic components were added to groundwater from the start of the test. It is a graph which shows the result of the switching test which performed the test. It is a graph which shows the result of the switching test which added the carbon tetrachloride so that it might be set to 1 mg / L in Example 3 of this invention, and performed the VOC decomposition | disassembly test by switching from anaerobic conditions to aerobic conditions. It is a graph which shows the result of having confirmed the decomposition effect about an aromatic nitro compound and an aromatic chlorine compound in Example 4 of this invention. It is a graph which shows the result of having done the effect test of the gas addition in the switching from anaerobic to aerobic about 50 mg / L trichloroethane in Example 5 of this invention. It is a graph which shows the result of having conducted the column test in Example 6 of this invention and performing the effect test of the anaerobic component type | system | group. It is a graph which shows the result of having conducted the effect test at the time of adding sucrose fatty acid ester to the anaerobic component type | system | group in the column test shown in FIG. It is a graph which shows the result of having examined the appropriate range of pH in Example 7 of this invention. It is a graph which shows the result of having examined the appropriate range of TOC density | concentration in Example 8 of this invention. It is a graph which shows progress of the VOC contamination density | concentration in the observation well 1 in Example 9 of this invention. It is a graph which shows progress of the VOC contamination density | concentration in the observation well 2 in Example 9 of this invention. It is a graph which shows progress of the VOC contamination density | concentration in the observation well 3 in Example 9 of this invention. It is a graph which shows progress of the TOC density | concentration in each well in Example 9 of this invention. It is a graph which shows progress of DO concentration in each well in Example 9 of this invention.

Embodiments of the present invention will be described below.
The medium targeted by the present invention is, for example, soil, groundwater or sediment in which indigenous microorganisms are generally present, but if the medium is an environment where microorganisms can inhabit, the method of adding microorganisms from the outside can also be used. The same effect can be obtained.
The purification agent of the present invention is added to a medium such as soil in contaminated areas, groundwater or sediment.

The effect of the restoration can be enhanced by setting the blending ratio of each substance constituting the purifying agent of the present invention in accordance with the soil to be restored.
Further, the form of the purifier is solid, liquid, slurry, etc., and is determined based on the geological state of the stratum in the contaminated area and the contamination status of the contaminated area. As a supply method, for example, a method in which the solution is dissolved in water and supplied to the medium is generally used, but the same effect can be obtained by a method of mixing with the medium by a machine.

The organochlorine compound having 3 or more chlorine atoms to be detoxified by the present invention is, for example, tetrachloroethylene, trichloroethylene, 1,1,1-trichloroethane, 1,1,2-trichloroethane, carbon tetrachloride, or A substance such as chloroform, and a nitro compound is, for example, a substance such as trifluralin, 4-nitroaniline, nitenpyram, 4-nitrophenol, nitrophene, nitrobenzene, nitromethane, parathion, pentachloronitrobenzene, furyl flamide, methyl parathion, or chloropicrin. Although there is, it is not limited to these.

Examples of the organic compound having 2 or less chlorine atoms include dichloromethane, 1,1-dichloroethane, 1,2-dichloroethane, 1,1-dichloroethylene, cis-1,2-dichloroethylene, and trans-1,2-dichloroethylene. 1,2-dichloropropane, 1,3-dichloropropene and dichlorobenzene, but are not limited to these as long as they are organic compounds having 2 or less chlorine atoms.

The microorganisms used for detoxification with the purifying agent of the present invention are microorganisms that are present in contaminated soil and can be grown in the same manner as general microorganisms, and include inorganic salts, nitrogen sources, and other nutrient sources. It is a microorganism that can grow in an inorganic nutrient medium, an organic nutrient medium, and the like, and can detoxify an organic chlorine compound. The contaminant detoxifying agent and detoxifying method of the present invention can also be applied to cases where foreign microorganisms are mixed, recombinant microorganisms prepared from genes extracted from microorganisms are used, or microorganisms are immobilized on a carrier.

The aerobic component system composed of one or more of phosphate, ammonium salt, nitrate, potassium, sodium, calcium, and iron compound contained in the cleaning agent of the present invention is the growth of microorganisms that decompose pollutants, Effective as a nutrient source for activation. The type and amount of the substance to be used are selected according to the type and concentration of the target pollutant, the type of medium, the type of microorganism used, and the like.

When supplying oxygen, the supply method is not limited, either by air supply or by kneading peroxide such as hydrogen peroxide, sodium percarbonate, magnesium peroxide, calcium peroxide or the like into the soil. A method of dissolving in water and supplying to the medium in the form of dissolved oxygen is preferable from the viewpoint of diffusion in the medium and spreading of the effect. The most suitable method is to inject aerobic microorganisms that decompose the target pollutants by injecting high-concentration oxygen water into an aerobic state with a dissolved oxygen concentration of 2 mg / L or more and an ORP value of 0 mV or more. From the viewpoint of activation, it is preferable.

Methane, ethane, ethylene, propane, or butane is selected according to the type and concentration of the pollutant from the viewpoint of supplying a carbon source to the aerobic microorganism that decomposes the target pollutant. It is desirable that Since the form to be used is a gas body at a standard temperature, there are a method of directly blowing into a medium and a method of dissolving and supplying water. A method of supplying to the medium in a form dissolved in water is preferable from the viewpoint of diffusion in the medium and spreading of the effect.

Depending on the pollution situation, the main pollution may be organochlorine compounds with 2 chlorines or less. In that case, the anaerobic component system, high-concentration oxygen water or this can be used directly without anaerobic treatment with the anaerobic component system. In addition, water in which at least one of methane, ethane, ethylene, propane, and butane is dissolved can be injected into the medium for purification.

Further, the dechlorination by anaerobic microorganisms is promoted by other anaerobic bioremediation purification agents to obtain an organic chlorine compound of 2 or less chlorination, and in combination with this, the organochlorine compound contamination medium of the present invention is then used. A method of promoting detoxification by aerobic microorganisms using a purification agent and a purification method can also be employed.
In the present invention, in order to quickly detoxify organochlorine compounds by using microorganisms, it is generally necessary to apply in an environment where microorganisms can live suitably or to form and manage the environment.

One or more of whey, lactose, sucrose, glucose, molasses, starch, soy milk, polylactic acid, xanthan gum and acetic acid, propionic acid, lactic acid, butyric acid and salts thereof that may be contained in the cleaning agent of the present invention One or more yeast extract, peptone, casamino acid, malt extract, beef extract, meat extract, chicken extract, polypeptone, gelatin and peanut oil, palm oil, benbag oil, sunflower oil, rice bran oil, soybean oil , Corn oil, rapeseed oil, linseed oil, cottonseed oil, olive oil, tung oil, grape oil and cyanocobalamin, hydroxycobalamin, methylcobalamin, biotin, folic acid, thiamine, riboflavin, ascorbic acid, pantothenic acid, ergocalciferol, phenoquinone, Three or more β-glucans and magnesium, iron, Barth, zinc and anaerobic component composed of one or more of these salts, growth of microorganisms degrade pollutants, are effective as Sekiru nutrient source activated. The type and amount of the substance to be used are selected according to the type and concentration of the target pollutant, the type of medium, the type of microorganism used, and the like.

Stearoyl lactic acid, sucrose fatty acid ester, dihexyl sulfosuccinic acid, alkyldiphenyl oxide disulfonic acid, polyethylene glycol dodecyl ether, lauroyl lactic acid, nonylphenol ethoxylate, polyoxyethylene sorbitan monooleate, dioctylsodium sulfosuccinate, polyoxylene-para -Isooctylphenone is a substance that has the effect of increasing the mobility of pollutants from soil to water.
It is effective for enhancing the usability (bioavailability) when microorganisms detoxify the target substance, and is a low-hazardous substance used as a food additive in the food industry field.

Under the above conditions, the present invention can quickly detoxify organochlorine compounds, particularly dichlorinated or less organochlorine compounds. Therefore, it is a purification method that can reduce the burden on the environment, the short construction period, and the cost in a contaminated medium that has been difficult or time-consuming by conventional bioremediation by anaerobic microorganisms and can be made harmless.
Hereinafter, this method will be described in more detail with reference to examples. However, the technical scope of the present invention is not limited to these examples.

In order to decompose an organic chlorine compound whose pollutant is 3 chlorine or more into an organic chlorine compound of 2 chlorine or less, it is necessary to form an anaerobic state and promote the growth and activation of anaerobic microorganisms. Then, the component which forms and maintains an anaerobic state and promotes the growth of anaerobic microorganisms was examined.
500ml glass bottle with whey, lactose, sucrose, glucose, molasses, starch, soy milk, polylactic acid, xanthan gum and acetic acid, propionic acid, lactic acid, butyric acid and yeast extract, peptone, casamino acid, malt extract, beef extract , Meat extract, chicken extract, polypeptone, gelatin and peanut oil, palm oil, bean oil, sunflower oil, rice bran oil, soybean oil, corn oil, rapeseed oil, linseed oil, cottonseed oil, olive oil, tung oil, grape One kind was selected from oil, and a 500 ml glass bottle was filled with activated sludge and water as a microorganism source. The 500 ml glass vial was allowed to stand at 35 ° C.

The anaerobic degree was determined by measuring the ORP value, and measuring changes in the concentration of hydrogen used as a respiration source of anaerobic microorganisms, the number of bacteria, and the organic carbon concentration (TOC) value important for maintaining an anaerobic state.
The hydrogen concentration was confirmed by gas chromatography using a TCD detector (hereinafter referred to as GC-TCD), and the number of bacteria was measured after applying test water to a plate medium and culturing at 30 ° C. for 2 days. The number of colonies was counted. The ORP value was measured with an ORP meter, and the TOC value was measured with a TOC meter. As a result, it became as shown in Table 1.

By using solid milk (component I), acetate salt (component II), casamino acid (component III), soybean oil (component IV) (No. 5 combination in Table 1), ORP value drop, TOC value It has been confirmed that maintenance and anaerobic can be formed and maintained.
No. No. 1 whey (component I) only. No. 2 solid milk (component I) and acetate (component II), or When 3 sucrose (component I), acetate (component II), and peptone (component III) were used, the ORP value was greatly reduced from the 7th day, and an anaerobic state was formed. However, on the 30th day, it was confirmed that the TOC value is rapidly decreasing, and that the number of bacteria is also decreasing, which is not suitable for maintaining an anaerobic state. . No. 16 propionate (component II) and peptone (component III) and linseed oil (component IV); When 17 yeast extracts (component III) and cottonseed oil (component IV) were used, the ORP value did not decrease significantly on the 7th day, and it took time to decrease the ORP value, and an anaerobic state was quickly formed. could not.

As Example 2, a VOC decomposition test under anaerobic conditions was performed.
Confirmed decomposition of pollutants under anaerobic conditions with solid milk (component I), acetate (component II), casamino acid (component III), and soybean oil (component IV) selected based on the results of Example 1 It was.

The first test 5L glass bottle is filled with groundwater so that it becomes full, and solid milk (component I), acetate (component II), casamino acid (component III), soybean oil (component IV), and tetrachloroethylene become 1 mg / L. And stored at room temperature. Periodic measurements were made on tetrachloroethylene, trichloroethylene, cis-1,2-dichloroethylene, vinyl chloride, and ethylene.

In addition, yeast extract (component III) was added to this nutrient source in the same manner as in the first test except for the second test .
In the third test and others, yeast extract (component III) and magnesium salt were added in the same manner as in the first test.
In the fourth test and others, the yeast extract (component III) and cyanocobalamin were added in the same manner as in the first test.
In the fifth test and the like, yeast extract (component III), magnesium salt and cyanocobalamin were added in the same manner as in the first test.

Similarly, instead of 1 mg / L tetrachloroethylene, 100 mg / L tetrachloroethylene, or 50 mg / L, 1 mg / L trichloroethane, and 1 mg / L carbon tetrachloride were added for the test. The results are shown in FIGS.

In each of the above tests, each chlorine compound to be detoxified is decomposed by microorganisms in the following order and detoxified.
(I) Tetrachloroethylene Tetrachloroethylene is decomposed in the order of trichlorethylene, cis-1,2-dichloroethylene, vinyl chloride, and ethylene to render it harmless.
(Ii) Trichloroethane Trichloroethane is decomposed in the order of dichloroethane, chloroethane, and ethane to make it harmless.
(Iii) Carbon tetrachloride Carbon tetrachloride is decomposed and rendered harmless in the order of trichloromethane, dichloromethane, chloromethane, and methane.

As shown in FIGS. 1 and 2, in the first test, it was confirmed that only 1 mg / L tetrachlorethylene was decomposed.
As shown in FIGS. 3 to 18, in the second to fifth tests, the decomposition of trichloroethane and cis-1,2-dichloroethylene was also confirmed. Moreover, as shown in FIG. 19, about the 5th test, it was able to confirm also about decomposition | disassembly of carbon tetrachloride and chloroform. However, the decomposition of dichloromethane could not be confirmed.

A VOC decomposition test was performed by switching from anaerobic conditions to aerobic conditions.
Phosphate and ammonium salt used under anaerobic conditions and anaerobic conditions comprising solid milk, acetate, casamino acid, soybean oil, yeast extract, cyanocobalamin, and magnesium salt components that were most effective in Example 2. By switching from anaerobic conditions to aerobic conditions using an aerobic component system consisting of nitrate, potassium, sodium, calcium, and iron compounds, it was confirmed whether compounds of 2 chlorine or less were rapidly decomposed.

An anaerobic component system consisting of solid milk, acetate salt, casamino acid, soybean oil, yeast extract, cyanocobalamin, and magnesium salt and groundwater are filled in a 5 L glass bottle, and tetrachlorethylene is added to a concentration of 100 mg / L. And stored at room temperature. After adding the anaerobic component system, when the decomposition of the compound with 3 or more chlorine has been confirmed, an aerobic component system composed of phosphate, ammonium salt, nitrate, potassium, sodium, calcium, iron compound is added, and oxygen gas The test was continued by injection so that the OPR value was 0 mV or more.

During the test period, measurements were made periodically for tetrachlorethylene, trichloroethylene, cis-1,2-dichloroethylene, vinyl chloride, and ethylene.
Similarly, instead of 100 mg / L tetrachloroethylene, 50 mg / L trichloroethane and 1 mg / L carbon tetrachloride were added for the test.
Also, anaerobic components consisting of solid milk, acetate, casamino acid, soybean oil, yeast extract, cyanocobalamin, magnesium salt and aerobic consisting of phosphate, ammonium salt, nitrate, potassium, sodium, calcium, iron compound The component system and groundwater were added to full water, tetrachloroethylene was added to 100 mg / L, and the mixture was stored at room temperature. On the 60th day from the start of the test, it was possible to confirm the decomposition of the compound of 3 chlorines or more. Thereafter, until 90 days, since the decomposition of vinyl chloride was slow, on the 90th day, oxygen gas was injected to test the OPR value to be 0 mV or more.

Fifth test results under anaerobic conditions based on an anaerobic component system comprising the components of solid milk, acetate salt, casamino acid, soybean oil, yeast extract, cyanocobalamin, and magnesium salt shown in Example 2 (FIGS. 16, 18, and 19) And anaerobic conditions consisting of solid milk, acetate, casamino acid, soybean oil, yeast extract, cyanocobalamin, magnesium salt components, and then phosphate, ammonium salt, nitrate, potassium, sodium Comparison of test results (shown in FIG. 20 to FIG. 23) in which an aerobic component system composed of calcium, iron compounds is added and switched to aerobic conditions shows that the tetrachlorethylene test switched to aerobic conditions on the 90th day and 120th day. The degradation of vinyl chloride is progressing rapidly in the eyes, and in the trichloroethane test, switching is made on the 30th day, and on the 60th day. Is, dichloroethane decomposition was observed. In addition, the carbon tetrachloride test was switched to the 90th day, and the decomposition of dichloromethane was confirmed on the 120th day.
Even when an anaerobic component system and an aerobic component system are added to the groundwater from the start of the test, it can be confirmed that the decomposition of vinyl chloride proceeds rapidly as in FIG. 21 by switching to the aerobic condition on the 90th day. (FIG. 22).
From this, it was confirmed that by switching to aerobic conditions, organochlorine compounds of 2 chlorines or less were rapidly decomposed.

We confirmed the detoxification effect on aromatic chlorine compounds and aromatic nitro compounds by switching from anaerobic conditions to aerobic conditions.
An anaerobic component system consisting of solid milk, acetate, casamino acid, soybean oil, yeast extract, cyanocobalamin, and magnesium salt and groundwater are placed in a 5 L glass bottle to make it full, and 1 mg / dichlorobenzene (aromatic chlorine compound) is added. It added so that it might become L, and it stored at room temperature. On the 30th day from the start of the test, an aerobic component system consisting of phosphate, ammonium salt, nitrate, potassium, sodium, calcium, and iron compounds was added, and the OPR value was set to 0 mV or more by oxygen gas injection. Continued.
Similarly, 1 mg / L nitrobenzene (aromatic nitro compound) was also tested. The results are shown in FIG.

After forming anaerobic conditions in the anaerobic component system consisting of components of solid milk, acetate, casamino acid, soybean oil, yeast extract, cyanocobalamin, magnesium salt, phosphate, ammonium salt, nitrate, potassium, sodium, calcium, In a test where an aerobic component system composed of an iron compound was added and switched to aerobic conditions, rapid decomposition of dichlorobenzene and nitrobenzene was confirmed.

An effect test of gas addition in switching from anaerobic to aerobic was performed.
Specifically, it was examined whether methane gas, ethane gas, and propane gas could serve as nutrient sources for microorganisms and accelerate the decomposition rate.

An anaerobic component system consisting of solid milk, acetate, casamino acid, soybean oil, yeast extract, cyanocobalamin, magnesium salt and groundwater are placed in a 5 L glass bottle so as to be filled with water, and added to 50 mg / L trichloroethane. Stored at room temperature. On the 30th day from the start of the test, we were able to confirm the decomposition of compounds with 3 or more chlorine, so we added an aerobic component system consisting of phosphate, ammonium salt, nitrate, potassium, sodium, calcium and iron compounds, and oxygen gas and propane The test was continued by injecting gas so that the OPR value was 0 mV or more.
During the test period, dichloroethane and ethane were measured periodically. The results are shown in FIG.

After forming anaerobic conditions in the anaerobic component system consisting of components of solid milk, acetate, casamino acid, soybean oil, yeast extract, cyanocobalamin, magnesium salt, phosphate, ammonium salt, nitrate, potassium, sodium, calcium, From the test in which an aerobic component system composed of an iron compound is added to switch to aerobic conditions (FIG. 21 showing the test results of Example 3), propane is further added and injected to decompose dichloroethane as shown in FIG. Was confirmed to be faster.

The column test confirmed whether or not the substance having the effect of increasing the mobility of the pollutant from the soil to the water has the effect of increasing the usability (bioavailability) when the microorganism detoxifies the target substance.

A column was prepared by packing 3 kg of a soil sample into a pipe of vinyl chloride. 3 columns of solid milk, acetate, casamino acid, soybean oil, yeast extract, cyanocobalamin, an anaerobic component system consisting of magnesium salts dissolved in water, solid milk, acetate, casamino acid 3 L of an anaerobic component system consisting of components of soybean oil, yeast extract, cyanocobalamin and magnesium salt dissolved in water was run on the 0th, 30th and 60th days. In addition, the concentrations of tetrachloroethylene, trichloroethylene, and cis-1,2-dichloroethylene in the solution passed on the 0th, 30th, 60th, and 90th days were measured. The results are shown in FIGS.

Day 30 when sucrose fatty acid ester is added to the anaerobic component system consisting of components of solid milk, acetate salt, casamino acid, soybean oil, yeast extract, cyanocobalamin, and magnesium salt, and then poured into the soil in the column (FIG. 27) However, tetrachloroethylene and trichlorethylene are not observed, but the concentration of cis-1,2-dichloroethylene produced by decomposition is increased. It is presumed that decomposition of tetrachlorethylene and trichlorethylene progresses in the column. In addition, due to the effect of sucrose fatty acid ester, when only an anaerobic component system consisting of components of solid milk, acetate, casamino acid, soybean oil, yeast extract, cyanocobalamin, and magnesium salt is used (FIG. 26), cis-1, 2-Dichloroethylene was eluted from the soil, and the results confirmed that the mobility from soil to water was increased, and that the use of microorganisms for detoxifying the target substance was improved.

The appropriate range of pH in the practice of the present invention was examined.
Place groundwater in a 500 mL glass bottle to fill it up, add anaerobic component system consisting of solid milk, acetate, casamino acid, soybean oil, yeast extract, cyanocobalamin, magnesium salt, and adjust the pH with hydrochloric acid and sodium hydroxide. After adjusting, tetrachlorethylene was added to 1 mg / L and the mixture was stored at room temperature. The results on the 60th day are shown in FIG.

When tested in an anaerobic state using an anaerobic component system comprising solid milk, acetate, casamino acid, soybean oil, yeast extract, cyanocobalamin, and magnesium salt (Example 2-5, Figs. 15 to 19), 60 days Tetrachlorethylene decomposes in the eyes. However, when the pH was set to 5.5 or lower and 9.0 or higher this time, as shown in FIG. 28 showing the result on the 60th day, the decomposition of tetrachlorethylene was delayed. From this, it was confirmed that it is desirable to maintain in the pH range of 5.5 to 9.0.

The appropriate range of the anaerobic component system addition concentration of the present invention was examined from the TOC value.
Place groundwater in a 500 mL glass bottle to fill it up, add anaerobic components consisting of solid milk, acetate, casamino acid, soybean oil, yeast extract, cyanocobalamin, and magnesium salt at each concentration, and add 1 mg / L of tetrachlorethylene. And added at room temperature. On day 120, measurements were made on tetrachlorethylene, trichloroethylene, cis-1,2-dichloroethylene, vinyl chloride and ethylene. The results are shown in FIG.

In a long-term test (about 120 days), when stored without aerobic conditions only with anaerobic components consisting of components of solid milk, acetate, casamino acid, soybean oil, yeast extract, cyanocobalamin, magnesium salt Also, cis-1,2-dichloroethylene (dichlorine compound) is decomposed. However, the speed can be increased by using aerobic conditions. When the TOC value was 50 mg / L or less, decomposition stopped with cis-1,2-dichloroethylene. At a TOC value of 50 mg / L or more, the test period was long, but cis-1,2-dichloroethylene was also decomposed. This confirms that an anaerobic component system consisting of components of solid milk, acetate, casamino acid, soybean oil, yeast extract, cyanocobalamin, and magnesium salt is desirably maintained at a concentration of 50 mg / L or more in the TOC value. did it.

A pilot test (in-situ test) was performed to confirm VOC decomposition.
Specifically, purification tests were conducted in the groundwater contaminated with organochlorine compounds. The purification test site has a target layer thickness of 5 m from the ground surface and a planar area of 10 m long × 10 m wide. In addition, in this purification test site, a sandy layer having a hydraulic conductivity of the order of 10 ⁻³ cm / second and the following clay layers of the order of 10 ⁻⁴ and 10 ⁻⁵ cm / second were distributed. In this test, contaminants such as tetrachlorethylene, dissolved oxygen (DO), ORP, pH, and TOC were measured. The organochlorine compound concentration was measured using a gas chromatograph mass spectrometer in accordance with an official analysis method (JIS-K0125).

On site, an anaerobic component system consisting of solid milk, acetate, casamino acid, soybean oil, yeast extract, cyanocobalamin, and magnesium salt was dissolved in tap water and poured into the groundwater from the injection well. Every 30 days for each observation well (observation well 1 (sand layer object): 1 to 2 m deep, observation well 2 (silt layer object): 2 to 4 m depth, observation well 3 (sand layer object): 4 to 5 m depth The chlorinated organic compound concentration, DO, ORP, pH, and TOC were measured at 30. On the 30th day, the formation where the TOC rose (observation well 1 (sand layer target): 1 to 2 m deep (FIG. 30). ), Observation well 3 (target sand layer): 4 to 5 m deep (Fig. 32)) showed anaerobic conditions, complete decomposition of tetrachloroethylene, and increase of cis-1,2-dichloroethylene.

The TOC has not risen, and the permeability is 10 ⁻⁴ , 10 ⁻⁵ cm / sec order (observation well 2 (silt layer target): 2 to 4 m depth (FIG. 31)) by the double packer method The anaerobic component system consisting of solid milk, acetate, casamino acid, soybean oil, yeast extract, cyanocobalamin, and magnesium salt was injected again by pressure injection with 0.1 to 0.2 MP. At this time, sucrose fatty acid ester was also added. On the 30th day after the pressure injection (60th day from the start of the test), the TOC rose in the observation well 2 silt layer (FIG. 33), and the complete decomposition of tetrachlorethylene was observed.

On the 60th day from the start of the test, three or more organochlorine compounds of tetrachlorethylene and trichlorethylene were decomposed in all the target geological formations, resulting in contamination with only two or less organochlorine compounds, so oxygen averaged 30 mg / L, Aerobic components consisting of phosphate, ammonium salt, nitrate, potassium, sodium, calcium, and iron compounds are dissolved in tap water in which 0.5 mg / L of methane is dissolved, and continued to groundwater at a flow rate of about 2 L / min. Injected. After injecting oxygen, methane, and aerobic components, the DO value increased in all observation wells and was maintained under aerobic conditions (FIG. 34). Moreover, the organochlorine compound density | concentration and DO, ORP, and pH were measured regularly.

In the contaminated area where the anaerobic component system consisting of components of solid milk, acetate, casamino acid, soybean oil, yeast extract, cyanocobalamin and magnesium salt was reached, decomposition to trichlorethylene was shown on the 30th day. On the 30th day, an anaerobic component system consisting of solid milk, acetate salt, casamino acid, soybean oil, yeast extract, cyanocobalamin, and magnesium salt was added, and sucrose fatty acid ester was added, and 0.1 to 0.2 MP by the double packer method. By the pressure injection by the pressure injection by, the decomposition proceeded rapidly even in the contaminated area (observation well 2) that was not decomposed by the natural injection (FIG. 31). In addition, after shifting to aerobic conditions, decomposition of compounds of 2 chlorines or less proceeded rapidly in all layers. From this, the quick purification effect in this invention has been confirmed.

Claims (18)

A cleaning agent comprising an aerobic component system that decomposes a compound in which two or less chlorines are bonded while maintaining an aerobic state by injecting into a medium with water in which a specific component gas is dissolved. An anaerobic component in which three or more chlorine-bonded compounds are decomposed by injecting the medium into an anaerobic state by injecting the medium into the medium contaminated with chlorine or a nitro-bonded compound to form two or less chlorine-bonded compounds. A purifying agent comprising a system and an aerobic component system that decomposes a compound in which two or less chlorines are bonded under an aerobic condition. 3. The aerobic component system decomposes a compound in which two or less chlorines are bonded while maintaining an aerobic state by injecting into a medium with water in which a specific component gas is dissolved. Purifier. The purifying agent according to claim 1 or 3, wherein the specific component gas is one or more of methane, ethane, propane and butane and oxygen. The purifying agent according to claim 2 or 3, wherein the anaerobic component system comprises one or more of carbon component, organic acid, organic acid salt, protein, vegetable oil, surfactant, vitamin and mineral. . The purifying agent according to claim 5, wherein the carbon component is one or more of whey, lactose, sucrose, glucose, molasses, starch, soy milk, polylactic acid, and xanthan gum. 6. The purifying agent according to claim 5, wherein the organic acid and a salt thereof are at least one of acetic acid, propionic acid, lactic acid, butyric acid and a salt thereof. The purification agent according to claim 5, wherein the protein is at least one of yeast extract, peptone, casamino acid, malt extract, beef extract, meat extract, chicken extract, polypeptone, and gelatin. The vegetable oil is one or more of peanut oil, palm oil, safflower oil, sunflower oil, rice bran oil, soybean oil, corn oil, rapeseed oil, linseed oil, cottonseed oil, olive oil, tung oil, grape oil The purification agent according to claim 5. Surfactant is stearoyl lactic acid, sucrose fatty acid ester, dihexyl sulfo succinic acid, alkyldiphenyl oxide disulfonic acid, polyethylene glycol dodecyl ether, lauroyl lactic acid, nonylphenol ethoxylate, polyoxyethylene sorbitan monooleate, dioctyl sodium sulfosuccinate, 6. The cleaning agent according to claim 5, which is one or more of polyoxylene-para-isooctylphenone and salts thereof. 6. The purification according to claim 5, wherein the vitamin is at least three of cyanocobalamin, hydroxycobalamin, methylcobalamin, biotin, folic acid, thiamine, riboflavin, ascorbic acid, pantothenic acid, ergocalciferol, phenoquinone, and β-glucan. Agent. The purification agent according to claim 5, wherein the mineral is one or more of magnesium, iron, cobalt, zinc, and salts thereof. The purifying agent according to claim 1 or 2, wherein the aerobic component system is one or more of phosphate, ammonium salt, nitrate, potassium, sodium, calcium, and iron compound. A step of maintaining an anaerobic state by an anaerobic component system and a step of switching to an aerobic state by an aerobic component system using the purifying agent according to any one of claims 1 to 13. A method for purifying a featured medium. * Dissolve the anaerobic component system 10 to 500 times in water and inject it into the target medium, pH 6.5 to 8.5, ORP value 0 mV or less, DO value 0.5 mg / L or less, TOC value 50 mg / L 15. The method for purifying a medium according to claim 14, wherein the medium is maintained at L or more. One or more of phosphate, ammonium salt, nitrate, potassium, sodium, calcium, iron compound to be 10-500 times in water in which one or more of methane, ethane, propane, butane and oxygen are dissolved Dissolving the gas component system and injecting it into the target medium, maintaining pH 6.5 to 8.5, ORP value 0 mV or more, DO value 2 mg / L or more, and electrical conductivity 50 μs / cm or more. 16. The method for purifying a medium according to claim 14 or 15, wherein the medium is purified. A step of dropping the cleaning agent according to claim 2, claim 5 or claim 13 to maintain an anaerobic state by an anaerobic component system and decomposing a compound having three or more chlorine bonded thereto, and methane after a predetermined period of time A method for purifying a medium comprising the step of injecting water in which a specific component gas composed of one or more of ethane, propane and butane and oxygen is dissolved into the medium and switching to an aerobic state. * The medium purification method according to any one of claims 14 to 17, wherein at least one of an anaerobic component system and an aerobic component system is pressure-injected.

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