JP6374239B2 - Nutrient for contaminated soil purification - Google Patents

Description

  The present invention relates to a soil purification nutrient for purifying contaminated soil containing an organochlorine compound in the field (in situ). More specifically, the present invention relates to a nutrient for soil purification for activating microorganisms that decompose organochlorine compounds contained in contaminated soil.

Tetrachloroethylene, trichlorethylene, dichloroethylene, and the like, which are organochlorine compounds, are widely used for degreasing and cleaning metals, cleaning for dry cleaning, refrigerants, and the like, and have high industrial utility value. However, organochlorine compounds are also harmful substances that cause liver damage and kidney damage to the human body, so soil contamination by these substances has become a serious social problem.
Therefore, as a method for remediating soil contaminated with these organic chlorine compounds, a method has been developed to activate nutrient-degrading bacteria by adding nutrients to microorganisms that are resident in the soil. Many methods of using an oil-in-water emulsion using liquid oil as a raw material as a nutrient have been proposed.

For example, Patent Document 1 discloses a liquid and fat, a nonionic surfactant, a soil and a groundwater purifier made of an emulsion obtained by emulsifying polyhydric alcohol and water in an oil-in-water type, and a melting point of 15 ° C. or lower. One of the features is that 20 to 70 parts of the liquid oil or fat is blended.
Patent Document 2 discloses a soil and groundwater purification agent composed of an emulsion obtained by emulsifying liquid oil and fat, a surfactant and water in an oil-in-water type, and is characterized by blending 20 to 80 parts of liquid oil and fat. One of them.
Patent Document 3 discloses a nutrient for purifying contaminated soil containing a vegetable oil emulsion and sodium caseinate as a stabilizing component, and is characterized by further containing a nitrogen source and a phosphorus source.
These soil, groundwater purification agents, and contaminated soil purification nutrients can all be said to work effectively in soil purification, but because the main component is an emulsion of liquid fats and oils, the decomposition activity is high, There was a problem that even if it was injected into the soil, it was decomposed early.

Moreover, as what makes a solid fatty acid a main component at normal temperature, for example, in patent document 4, the C10 or more fatty acid is embed | buried in soil, nitrate nitrogen and volatile organic compound in soil are included. A reduction method is disclosed, and Patent Document 5 discloses a soil and groundwater purification composition having a fatty acid or alcohol having 14 or more carbon atoms and a surfactant.
It can be said that those containing solid fatty acids at normal temperature also work effectively in soil purification, but the solid fatty acids as such are poorly permeable, agglomerating only the oil, and not being effective enough. there were.
Therefore, it is desired to provide a more useful nutrient for purifying contaminated soil that can solve these problems and has high soil permeability and high long-term stability at room temperature.

JP 2007-83169 A JP 2010-158653 A JP 2011-224497 A JP 2002-370085 A JP 2005-66425 A

  The present invention is highly permeable to soil and stable for a long period of time at room temperature, with respect to conventional emulsions of liquid fats and oils, and other contaminated soil purification nutrients containing fatty acids that are solid at room temperature as the main component. The objective is to provide a more useful and more useful nutrient for soil purification.

As a result of intensive studies to solve the above problems, the present inventors obtained vegetable oils and fats and / or processed fats and oils having an SFC (solid fat content) of 1 to 60 at 20 ° C. as raw oils and fats. The oil-in-water emulsified composition has been found to be a useful nutrient for purifying contaminated soil, having high soil permeability and high long-term stability at room temperature.
The contaminated soil purification nutrient of the present invention activates microorganisms that decompose organic chlorine compounds by mixing and infiltrating soil contaminated with organic chlorine compounds, and stabilizes the decomposition of organic chlorine compounds over a long period of time. It is possible to promote.

That is, the present invention relates to a nutrient for purifying contaminated soil shown in the following (1) to (7).
(1) A nutrient for purifying contaminated soil containing a vegetable oil and / or an oil-in-water emulsified composition using a processed oil and fat of the oil and fat as a raw oil and fat, wherein the raw oil and fat has an SFC of 1 to 60 A contaminated soil cleanup nutrient.
(2) The nutrient for purifying contaminated soil according to (1) above, wherein the SFC at 20 ° C. of the raw material fat is 1-30.
(3) The nutrient for purifying contaminated soil according to (1) or (2) above, comprising an oil-in-water emulsion composition having an average particle size of 0.5 to 1.0 μm.
(4) The nutrient for contaminated soil purification according to any one of (1) to (3) above, comprising an organic acid monoglyceride.
(5) The nutrient for purifying contaminated soil according to (4) above, wherein the organic acid monoglyceride is diacetyltartaric acid monoglyceride.
(6) A method for purifying contaminated soil, comprising a step of injecting the nutrient for purifying contaminated soil according to any one of (1) to (5) into soil.
(7) The method according to any one of (1) to (5) above, comprising a step of mixing and homogenizing an oil phase and a water phase containing vegetable oil and / or processed oil and fat of the oil and fat as a raw oil and fat. A method for producing a nutrient for cleaning contaminated soil.

  Since the nutrient for purifying contaminated soil according to the present invention is an oil-in-water emulsion of vegetable oil that is stable at room temperature for a long time, it is possible to stably purify contaminated soil for a long time by providing the nutrient. It becomes possible.

It is the figure which showed the result of the VOC decomposition | disassembly test in Example goods 4 (Test Example 4). It is the figure which showed the result of the VOC decomposition | disassembly test in Example goods 5 (Test Example 4). It is the figure which showed the result of the VOC decomposition | disassembly test in the comparative example product 1 (Test Example 4). It is the figure which showed the result of the VOC decomposition | disassembly test in the comparative example product 3 (Test Example 4). It is the figure which showed the change of pH when adding each emulsified oil-fat composition (Test Example 4).

The “nutrient for cleaning contaminated soil” of the present invention is activated by a microorganism that decomposes organic chlorine compounds by mixing with soil contaminated with organic chlorine compounds, and promotes the decomposition of organic chlorine compounds in the soil. A nutrient that can be used.
Here, the “organochlorine compound” to be decomposed in this embodiment means a volatile organochlorine compound that can be decomposed by microorganisms. Examples of such organic chlorine compounds include tetrachloroethylene (PCE), trichlorethylene (TCE), cis-1,2 dichloroethylene (cis-1, 2-DCE) and the like.

Any microorganism capable of decomposing organochlorine compounds contained in contaminated soil may be used as the microorganism having the ability to resolve these organochlorine compounds. Examples of such microorganisms include, for example, anaerobic archaea such as Methanobacteria, Methanosarcina, and Methanolobus, Acetobacteria, Desulfobacteria, Dehalobacter, Dehalobacterium, Dehalococoides And anaerobic microorganisms such as Clostridium.
By the reductive chlorination reaction by these anaerobic microorganisms, tetrachloroethylene and trichlorethylene can be decomposed into ethylene through cis-1,2 dichloroethylene and vinyl chloride in this order. That is, these anaerobic microorganisms can acquire energy and proliferate by a reductive chlorination reaction using hydrogen as an electron donor and tetrachloroethylene or the like as an electron acceptor.

Such a “contaminated soil cleaning nutrient” according to the present invention is a contaminated soil cleaning nutrient containing an oil-in-water emulsified composition using vegetable oil and / or processed oil of the oil as raw material fat. The nutrient oil for purifying contaminated soil having an SFC of 1 to 60 at 20 ° C. of the raw material fats and oils may be used.
The “nutrient for purifying contaminated soil” of the present invention is supplied in the state of an oil-in-water emulsion composition using vegetable oils and / or processed oils of the oils as raw oils and fats, and has the above-mentioned ability of organochlorine compounds. An anaerobic microorganism, which is a microorganism, has a hydrogen donor for reductive dechlorination of an organic chlorine compound. That is, the vegetable oil emulsion is gradually decomposed to produce an organic acid, and the organic acid is further decomposed to produce hydrogen. This hydrogen is used when anaerobic microorganisms reductively dechlorinate organochlorine compounds after the soil is anaerobic.

  As described above, the “nutrient for purifying contaminated soil” of the present invention may be a nutrient for purifying contaminated soil having an SFC of 1 to 60 at 20 ° C. of the raw oil and fat, and the SFC at the same temperature is 1 to 30. More preferably it is.

The “raw oil / fat” of the present invention may be any vegetable oil and / or processed oil / fat of vegetable oil. In addition, since this "raw material fat" is decomposed | disassembled by microorganisms, it is preferable that it is edible.
Examples of such vegetable oils include palm oil and coconut oil. The melting point of the fats and oils of such “raw oils and fats” can be adjusted by chemical treatment such as curing, transesterification and fractionation, and any of these chemical treatments may be used to obtain the desired melting point.
The “raw oil and fat” is preferably contained in an amount of 10 to 60 parts by weight in the “oil-in-water emulsion” serving as a nutrient for purifying contaminated soil. When the blending amount of the vegetable oil is less than 10 parts by weight, the stability of the emulsion is lowered, and it becomes difficult to obtain an oil-in-water emulsion that is stable at room temperature.
In addition, the greater the amount of “raw oil” blended, the less the amount of the “contaminated soil purification nutrient” of the present invention injected into the contaminated soil. There are significant operational advantages such as reduction of storage amount and shortening of construction work time for injection. For this reason, it is still more preferable that the compounding quantity of "raw material fat" shall be 20 weight part or more.
On the other hand, the greater the amount of “raw oil” is, the higher the viscosity is, and clogging is likely to occur when injected into contaminated soil. Therefore, the amount of “raw oil” may be less than 50 parts by weight. Further preferred. That is, the blending amount of the “raw oil and fat” in the “oil-in-water emulsion” is more preferably in the range of 20 to 50 parts by weight.

The “oil-in-water emulsion” serving as a nutrient for purifying contaminated soil of the present invention can be prepared by mixing and emulsifying an oil phase and an aqueous phase. As a result, dispersibility in contaminated soil is enhanced, and it becomes possible to provide an “oil-in-water emulsion” that is stable at room temperature for a long period of time.
In this oil phase, it is preferable to add lauric fats and surfactants as raw material fats, and it is particularly preferable to add both lauric fats and surfactants.
Examples of such lauric fats and oils include vegetable oils such as coconut oil or palm kernel oil, and these may be added singly or in combination of two or more.
As the surfactant added to the oil phase, organic acid monoglycerides such as diacetyltartaric acid monoglyceride and succinic acid monoglyceride are particularly preferable, and these may be added singly or in combination. By adding an organic acid monoglyceride, acid resistance and heat resistance can be imparted to the “oil-in-water emulsion” of the present invention. In addition, since this surfactant is also decomposed | disassembled by microorganisms, it is preferable that it is edible.
If necessary, a surfactant such as glycerin fatty acid ester, sorbitan fatty acid ester, propylene glycol fatty acid ester, sucrose fatty acid ester, soybean oil phospholipid can be added to this oil phase.
In the aqueous phase, surfactants such as glycerin fatty acid ester, sorbitan fatty acid ester, propylene glycol fatty acid ester, sucrose fatty acid ester, soybean oil phospholipid, and pH such as citrate and phosphate as necessary. Conditioners, and further proteins such as whey, casein, and nonfat dry milk can be added.

The “oil-in-water emulsion” prepared in this way is made from vegetable oil and fat containing solid fat and / or processed oil and fat as raw material fat, and the average particle size of the emulsion is 0.5 to 1.0 μm. It is preferable to adjust to the range.
Furthermore, it is preferable that 0.5 to 2.0 parts by weight of diacetyltartaric acid monoglyceride which is an organic acid monoglyceride is added to provide long-term stability at room temperature of the oil-in-water emulsion.

The "contaminated soil purification method" of the present invention refers to a purification method including the step of injecting the "contaminated soil purification nutrient" of the present invention into the soil, and if the contaminated soil can be purified, It may include other known processes.
Injecting the “contaminated soil purification nutrient” into the soil, the “contaminated soil purification nutrient” of the present invention is diluted to a necessary concentration of, for example, about 20 to 30 times, and then sprayed onto the contaminated soil. For example, a well for injection may be dug into contaminated soil and continuously injected.
In addition to dilution, the “nutrient for purifying contaminated soil” of the present invention may be used in a “contaminated soil purification method” after adding a pH adjusting agent to adjust to an optimum pH of microorganisms.

The “method for producing a nutrient for purifying contaminated soil” according to the present invention includes a step of mixing and homogenizing an oil phase and a water phase containing vegetable oil and / or processed oil of the oil as raw oil and fat. It refers to the manufacturing method of the contaminated soil purification nutrient.
Here, “homogenization” means adjusting the average particle diameter of the “nutrient for purifying contaminated soil” to a range of 0.5 to 1.0 μm using a homogenizer or the like.
If this manufacturing method is a method which can manufacture the "nutrient for contaminated soil purification" of this invention, you may include the other process conventionally known.

  EXAMPLES Hereinafter, although an Example, a comparative example, etc. are given and this invention is demonstrated further in detail, this invention is not limited to these.

By the following Examples 1 to 10, (Example products 1 to 10) of the present invention were obtained. Moreover, the comparative example goods 1-7 were obtained as a comparison. These emulsion stability and permeability were examined and evaluated according to the following evaluation criteria.
In addition, these average particle sizes are measured by a laser diffraction type particle size distribution measuring instrument (SALD-3100, Shimadzu Corp.), and a homogenous pressure (pre-homogeneous pressure, post-homogeneous) in a homogenizer for adjusting the particle size is measured. Homogeneous pressure) was recorded.
In the present invention, “%” and “part” represent “% by weight” and “part by weight” unless otherwise specified.

[Emulsification stability evaluation criteria]
The soil improver (oil-in-water emulsion) of the present invention or a comparative example product was added with 500 ppm of sodium azide for antiseptic treatment, and then dispensed in a standing pouch of about 200 ml. The liquid stability when this was left for 2 weeks under storage conditions in various temperature zones (5 ° C., 25 ° C., 35 ° C., 5 ° C. to 40 ° C.) was visually evaluated.
In the evaluation, the case where coagulation was observed under any temperature condition was rated as x, and the case where coagulation was not observed was rated as ◯.

(Permeability evaluation criteria)
The soil improver (oil-in-water emulsion) or the comparative product of the present invention was dissolved in water to obtain a 0.3% solution. 50 g of wet earth (mountain sand + clay (manufactured by Kanto Kasei Co., Ltd .: Tochi clay)) and 100 ml of the above 0.3% solution were added to a glass bottle, and the initial TOC (total organic carbon concentration) value was measured. Then, after shaking for 30 minutes, let stand for 1 to 6 hours, sample the supernatant, measure the TOC value in the supernatant, and compare the initial TOC value with the amount of soil adsorption (adsorption amount in dry soil) [ mg / kg] was calculated by the following formula 1. The dry soil weight was measured by separately drying 50 g of the wet soil. In addition, the tochi clay which is clay made by Kanto Kasei Co., Ltd. is about 70% of silicon dioxide (SiO ₂ ), about 14% of aluminum oxide (Al ₂ O ₃ ), and ferric oxide (Fe ₂ O ₃ ). About 6%.

[Formula 1]

  Next, the delay coefficient R was calculated by the following formulas 2 and 3 from the TOC value in the supernatant and the amount of soil adsorption. The delay coefficient represents the delay in movement due to the adsorption of each solute to the soil particles as a ratio when the water movement is 1. This delay coefficient R was used as a permeability evaluation criterion, and those having a numerical value of 100 or more were rated as x, and those having a value less than 100 were rated as ◯. In the evaluation, the lower this value, the better the permeability.

[Formula 2]

[Formula 3]

[Example 1]
Palm oil heated to 75 ° C. and processed fats and oils made from palm oil (SFC at 20 ° C .: 5) 30.5 parts, diacetyl tartaric acid monoglyceride 1.4 parts, soybean lecithin 0.32 parts, polyglycerin fatty acid An oil phase was prepared by adding 0.24 parts of ester.
A water phase was prepared by adding 0.4 part of polyglycerin fatty acid ester, 1.68 parts of sodium caseinate, and 0.8 part of sodium citrate to 64.66 parts of water heated to 70 ° C.
These oil phase and water phase mixtures were pre-emulsified with a TK homomixer at 1400 rpm, then homogenized with a homogenizer to an average particle size of 0.7 μm, heated at 144 ° C. for 8 seconds, The oil-in-water emulsion (Example product 1) was obtained by cooling to 0 degreeC.

[Example 2]
Palm oil heated to 75 ° C and processed fats and oils made from palm oil (SFC at 20 ° C: 30) 30.5 parts, 1.4 parts diacetyl tartaric acid monoglyceride, 0.32 parts soybean lecithin, polyglycerin fatty acid An oil phase was prepared by adding 0.24 parts of ester.
A water phase was prepared by adding 0.4 part of polyglycerin fatty acid ester, 1.68 parts of sodium caseinate, and 0.8 part of sodium citrate to 64.66 parts of water heated to 70 ° C.
These oil phase and water phase mixtures were pre-emulsified with a TK homomixer at 1400 rpm, then homogenized with a homogenizer to an average particle size of 0.7 μm, heated at 144 ° C. for 8 seconds, The oil-in-water emulsion (Example product 2) was obtained by cooling to 0 degreeC.

Example 3
30.5 parts of processed fats and oils (SFC at 20 ° C .: 60) made from palm kernel oil heated to 75 ° C., 1.4 parts of diacetyl tartaric acid monoglyceride, 0.32 parts of soybean lecithin, polyglycerol fatty acid ester 0 .24 parts were added to prepare an oil phase.
A water phase was prepared by adding 0.4 part of polyglycerin fatty acid ester, 1.68 parts of sodium caseinate, and 0.8 part of sodium citrate to 64.66 parts of water heated to 70 ° C.
These oil phase and water phase mixtures were pre-emulsified with a TK homomixer at 1400 rpm, then homogenized with a homogenizer to an average particle size of 0.7 μm, heated at 144 ° C. for 8 seconds, The oil-in-water emulsion (Example product 3) was obtained by cooling to 0 degreeC.

Example 4
Palm oil heated to 75 ° C. and processed fats and oils made from palm oil (SFC at 20 ° C .: 8) 30.5 parts, diacetyl tartaric acid monoglyceride 1.4 parts, soy lecithin 0.32 parts, polyglycerin fatty acid An oil phase was prepared by adding 0.24 parts of ester.
A water phase was prepared by adding 0.4 part of polyglycerin fatty acid ester, 1.68 parts of sodium caseinate, and 0.8 part of sodium citrate to 64.66 parts of water heated to 70 ° C.
These oil phase and water phase mixtures were pre-emulsified with a TK homomixer at 1400 rpm, then homogenized with a homogenizer to an average particle size of 0.7 μm, heated at 144 ° C. for 8 seconds, The oil-in-water emulsion (Example product 4) was obtained by cooling to 0 degreeC.

Example 5
30.5 parts of palm oil and palm oil heated to 75 ° C. (SFC at 20 ° C .: 24) 30.5 parts, diacetyl tartaric acid monoglyceride 1.4 parts, soybean lecithin 0.32 parts, polyglycerin fatty acid An oil phase was prepared by adding 0.24 parts of ester.
A water phase was prepared by adding 0.4 part of polyglycerin fatty acid ester, 1.68 parts of sodium caseinate, and 0.8 part of sodium citrate to 64.66 parts of water heated to 70 ° C.
These oil phase and water phase mixtures were pre-emulsified with a TK homomixer at 1400 rpm, then homogenized with a homogenizer to an average particle size of 0.7 μm, heated at 144 ° C. for 8 seconds, The oil-in-water emulsion (Example product 5) was obtained by cooling to 0 degreeC.

[Comparative product 1]
To 30.5 parts of rapeseed oil (SFC: 0 at 20 ° C.) heated to 75 ° C., 1.4 parts of diacetyl tartaric acid monoglyceride, 0.32 parts of soybean lecithin, and 0.24 part of polyglycerol fatty acid ester were added. An oil phase was prepared.
A water phase was prepared by adding 0.4 part of polyglycerin fatty acid ester, 1.68 parts of sodium caseinate, and 0.8 part of sodium citrate to 64.66 parts of water heated to 70 ° C.
These oil phase and water phase mixtures were pre-emulsified with a TK homomixer at 1400 rpm, then homogenized with a homogenizer to an average particle size of 0.7 μm, heated at 144 ° C. for 8 seconds, By cooling to 0 ° C., an oil-in-water emulsion (Comparative Example Product 1) was obtained.

[Comparative product 2]
30.5 parts of processed oil (SFC at 20 ° C .: 65) made from palm kernel oil heated to 75 ° C., 1.4 parts of diacetyl tartaric acid monoglyceride, 0.32 parts of soybean lecithin, polyglycerin fatty acid ester 0 .24 parts were added to prepare an oil phase.
A water phase was prepared by adding 0.4 part of polyglycerin fatty acid ester, 1.68 parts of sodium caseinate, and 0.8 part of sodium citrate to 64.66 parts of water heated to 70 ° C.
These oil phase and water phase mixtures were pre-emulsified with a TK homomixer at 1400 rpm, then homogenized with a homogenizer to an average particle size of 0.7 μm, heated at 144 ° C. for 8 seconds, By cooling to ° C., an oil-in-water emulsion (Comparative Example Product 2) was obtained.

[Comparative product 3]
30.5 parts of processed oil (SFC at 20 ° C .: 82) made from palm kernel oil heated to 75 ° C., 1.4 parts diacetyl tartaric acid monoglyceride, 0.32 parts soybean lecithin, polyglycerin fatty acid ester 0 .24 parts were added to prepare an oil phase.
A water phase was prepared by adding 0.4 part of polyglycerin fatty acid ester, 1.68 parts of sodium caseinate, and 0.8 part of sodium citrate to 64.66 parts of water heated to 70 ° C.
These oil phase and water phase mixtures were pre-emulsified with a TK homomixer at 1400 rpm, then homogenized with a homogenizer to an average particle size of 0.7 μm, heated at 144 ° C. for 8 seconds, By cooling to ° C., an oil-in-water emulsion (Comparative Example product 3) was obtained.

[Test Example 1]
With respect to these Example products 1 to 5 and Comparative Example products 1 to 3, the emulsion stability and permeability were examined according to the evaluation criteria, and the results obtained are shown in Table 1.
In addition, comprehensive evaluation was set to x when the evaluation result of at least one of emulsification stability and permeability was x. Hereinafter, overall evaluation was similarly shown in the Examples and Comparative Examples.

Example 6
Palm oil heated to 75 ° C and processed fats and oils made from palm oil (SFC at 20 ° C: 10) 30.5 parts, 1.4 parts of diacetyl tartaric acid monoglyceride, 0.32 parts of soybean lecithin, polyglycerin fatty acid An oil phase was prepared by adding 0.24 parts of ester.
A water phase was prepared by adding 0.4 part of polyglycerin fatty acid ester, 1.68 parts of sodium caseinate, and 0.8 part of sodium citrate to 64.66 parts of water heated to 70 ° C.
These oil phase and water phase mixtures were pre-emulsified with a TK homomixer at 1400 rpm, then homogenized with a homogenizer to an average particle size of 0.5 μm, heated at 144 ° C. for 8 seconds, The oil-in-water emulsion (Example product 6) was obtained by cooling to 0 degreeC.

Example 7
Palm oil heated to 75 ° C and processed fats and oils made from palm oil (SFC at 20 ° C: 10) 30.5 parts, 1.4 parts of diacetyl tartaric acid monoglyceride, 0.32 parts of soybean lecithin, polyglycerin fatty acid An oil phase was prepared by adding 0.24 parts of ester.
A water phase was prepared by adding 0.4 part of polyglycerin fatty acid ester, 1.68 parts of sodium caseinate, and 0.8 part of sodium citrate to 64.66 parts of water heated to 70 ° C.
These oil phase and water phase mixtures were pre-emulsified with a TK homomixer at 1400 rpm, then homogenized with a homogenizer to an average particle size of 0.7 μm, heated at 144 ° C. for 8 seconds, The oil-in-water emulsion (Example product 7) was obtained by cooling to 0 degreeC.

Example 8
Palm oil heated to 75 ° C and processed fats and oils made from palm oil (SFC at 20 ° C: 10) 30.5 parts, 1.4 parts of diacetyl tartaric acid monoglyceride, 0.32 parts of soybean lecithin, polyglycerin fatty acid An oil phase was prepared by adding 0.24 parts of ester.
A water phase was prepared by adding 0.4 part of polyglycerin fatty acid ester, 1.68 parts of sodium caseinate, and 0.8 part of sodium citrate to 64.66 parts of water heated to 70 ° C.
These oil phase and aqueous phase mixtures were pre-emulsified with a TK homomixer at 1400 rpm, then homogenized with a homogenizer so that the average particle size was 1.0 μm, heated at 144 ° C. for 8 seconds, By cooling to 0 ° C., an oil-in-water emulsion (Example Product 8) was obtained.

[Comparative product 4]
Palm oil heated to 75 ° C and processed fats and oils made from palm oil (SFC at 20 ° C: 10) 30.5 parts, 1.4 parts of diacetyl tartaric acid monoglyceride, 0.32 parts of soybean lecithin, polyglycerin fatty acid An oil phase was prepared by adding 0.24 parts of ester.
A water phase was prepared by adding 0.4 part of polyglycerin fatty acid ester, 1.68 parts of sodium caseinate, and 0.8 part of sodium citrate to 64.66 parts of water heated to 70 ° C.
These oil phase and water phase mixtures were pre-emulsified with a TK homomixer at 1400 rpm, then homogenized with a homogenizer to an average particle size of 0.3 μm, heated at 144 ° C. for 8 seconds, By cooling to 0 ° C., an oil-in-water emulsion (Comparative Example Product 4) was obtained.

[Comparative product 5]
Palm oil heated to 75 ° C and processed fats and oils made from palm oil (SFC at 20 ° C: 10) 30.5 parts, 1.4 parts of diacetyl tartaric acid monoglyceride, 0.32 parts of soybean lecithin, polyglycerin fatty acid An oil phase was prepared by adding 0.24 parts of ester.
A water phase was prepared by adding 0.4 part of polyglycerin fatty acid ester, 1.68 parts of sodium caseinate, and 0.8 part of sodium citrate to 64.66 parts of water heated to 70 ° C.
These oil phase and water phase mixtures were pre-emulsified with a TK homomixer at 1400 rpm, then homogenized with a homogenizer to an average particle size of 1.5 μm, heated at 144 ° C. for 8 seconds, By cooling to ° C., an oil-in-water emulsion (Comparative Example Product 5) was obtained.

[Test Example 2]
The example products 6 to 8 and the comparative example products 4 and 5 were examined for emulsion stability and permeability according to the evaluation criteria, and the results obtained are shown in Table 2.

Example 9
Palm oil heated to 75 ° C and processed fats and oils made from palm oil (SFC at 20 ° C: 10) 30.5 parts, diacetyl tartaric acid monoglyceride 1.0 part, soy lecithin 0.32 part, polyglycerin fatty acid An oil phase was prepared by adding 0.24 parts of ester.
A water phase was prepared by adding 0.4 part of polyglycerol fatty acid ester, 1.68 parts of sodium caseinate and 0.8 part of sodium citrate to 65.06 parts of water heated to 70 ° C.
These oil phase and water phase mixtures were pre-emulsified with a TK homomixer at 1400 rpm, then homogenized with a homogenizer to an average particle size of 0.7 μm, heated at 144 ° C. for 8 seconds, By cooling to 0 ° C., an oil-in-water emulsion (Example Product 9) was obtained.

Example 10
Palm oil heated to 75 ° C. and processed fats and oils made from palm oil (SFC at 20 ° C .: 10) 30.5 parts, diacetyl tartaric acid monoglyceride 2.0 parts, soybean lecithin 0.32 parts, polyglycerin fatty acid An oil phase was prepared by adding 0.24 parts of ester.
A water phase was prepared by adding 0.4 parts of polyglycerin fatty acid ester, 1.68 parts of sodium caseinate and 0.8 parts of sodium citrate to 64.06 parts of water heated to 70 ° C.
These oil phase and water phase mixtures were pre-emulsified with a TK homomixer at 1400 rpm, then homogenized with a homogenizer to an average particle size of 0.7 μm, heated at 144 ° C. for 8 seconds, The oil-in-water emulsion (Example product 10) was obtained by cooling to 0 degreeC.

[Comparative product 6]
Palm oil heated to 75 ° C. and processed fats and oils made from palm oil (SFC at 20 ° C .: 10) 30.5 parts, diacetyl tartaric acid monoglyceride 0.4 parts, soybean lecithin 0.32 parts, polyglycerin fatty acid An oil phase was prepared by adding 0.24 parts of ester.
A water phase was prepared by adding 0.4 part of polyglycerol fatty acid ester, 1.68 parts of sodium caseinate, and 0.8 part of sodium citrate to 65.66 parts of water heated to 70 ° C.
These oil phase and water phase mixtures were pre-emulsified with a TK homomixer at 1400 rpm, then homogenized with a homogenizer to an average particle size of 0.7 μm, heated at 144 ° C. for 8 seconds, By cooling to 0 ° C., an oil-in-water emulsion (Comparative Example Product 6) was obtained.

[Comparative product 7]
Palm oil heated to 75 ° C and processed fats and oils made from palm oil (SFC at 20 ° C: 10) 30.5 parts, diacetyl tartaric acid monoglyceride 2.8 parts, soybean lecithin 0.32 parts, polyglycerin fatty acid An oil phase was prepared by adding 0.24 parts of ester.
A water phase was prepared by adding 0.4 part of polyglycerol fatty acid ester, 1.68 parts of sodium caseinate, and 0.8 part of sodium citrate to 63.26 parts of water heated to 70 ° C.
These oil phase and water phase mixtures were pre-emulsified with a TK homomixer at 1400 rpm, then homogenized with a homogenizer to an average particle size of 0.7 μm, heated at 144 ° C. for 8 seconds, By cooling to ° C., an oil-in-water emulsion (Comparative Example product 7) was obtained.

[Test Example 3]
The example products 6, 9, and 10 and the comparative example products 6 and 7 were examined for emulsion stability and permeability according to the evaluation criteria, and the obtained results are shown in Table 3.

[Test Example 4]
Using Example Product 4, Example Product 5, Comparative Product 1 and Comparative Product 3, the resolution of the volatile organic compound (VOC) was evaluated.
Evaluation is made by adding 140 g (wet earth) of soil (mountain sand: clay (manufactured by Kanto Kasei Co., Ltd./tochi clay) = 10: 1) to a 140 mL-medium bottle, 75 mL of tap water, and a readily degradable nutrient As follows: 2.3 mL of 10% sodium gluconate solution, 1.4 mL of 5% sodium bicarbonate solution, 5 mL of VOC-degrading bacteria culture solution, 5 mL of trichlorethylene (TCE) solution (TCE concentration: about 900 mg / L), about 2 By culturing at 23 to 25 ° C. for a month, VOC-decomposing microorganisms were grown, and it was confirmed that TCE and 1,2-dichloroethylene which is a decomposition product of TCE were decomposed.
Next, 7.7 mL of the emulsified oil / fat composition solution (about 30% solution) of Example Product 4, Example Product 5, Comparative Product 1 and Comparative Product 3 was added, and at the same time, a TCE solution (TCE concentration: about 30%). The VOC concentration when 2 mL of 900 mg / L) was added was measured. In order to confirm the persistence of the resolution, when it was confirmed that VOC was decomposed, 2 mL of a TCE solution (TCE concentration: about 900 mg / L) was additionally added, and the VOC concentration was measured in the same manner. The results are shown in FIGS.
In addition, FIG. 5 shows changes in pH in each test section. As a control group, the numerical value of the group which does not add an emulsified oil-fat composition solution was illustrated.

From the results of FIGS. 1 to 4, it was revealed that the comparative product 1 is a liquid fat, but the resolution does not last after the day when TCE was additionally added. On the other hand, Example Product 4 and Example Product 5 maintained good VOC resolution, and showed good VOC resolution even after 60 days had elapsed after addition. Further, it was clarified that the comparative example product 3 has a lower decomposition rate than the example product 4 and the example product 5, and the decomposition efficiency is poor.
Moreover, from the result of FIG. 5, it became clear that the pH of the comparative example product 1 is significantly lower than that of the other emulsified oil and fat compositions. That is, in Comparative Example Product 1, as one of the factors that cause VOC decomposition not proceeding, it is considered that the Comparative Example Product 1 was easily microbially decomposed and an organic acid was excessively generated, so that the pH was lowered.

  From the results of Test Example 1 to Test Example 4, as a contaminated soil purification nutrient, in order to expect both emulsification stability and permeability, and to maintain efficient VOC resolution in the long term, It has become clear that it is appropriate to set the SFC value at 20 ° C. within the range of 1-60.

  Since the nutrient for purifying contaminated soil according to the present invention is an oil-in-water emulsion of vegetable oil that is stable at room temperature for a long time, it is possible to stably purify contaminated soil for a long time by providing the nutrient. It becomes possible. Furthermore, by adjusting the physical properties of fats and oils contained in the oil-in-water emulsion, it is possible to provide a nutrient for purifying contaminated soil having an optimum purification rate and effective period according to the temperature environment.

Claims (5)

A nutrient for purifying contaminated soil, comprising an oil- in- water emulsion composition having an average particle size of 0.5 to 1.0 μm using vegetable oil and / or processed oil and fat as raw material fat, Ri SFC 1 to 60 der at 20 ° C., and contaminated soil purifying nutrient containing 0.5 to 2.0 parts by weight of organic acid monoglyceride.   The nutrient for purifying contaminated soil according to claim 1, wherein the raw oil and fat has an SFC of 1 to 30 at 20 ° C. The nutrient for purifying contaminated soil according to claim 1 or 2 , wherein the organic acid monoglyceride is diacetyltartaric acid monoglyceride. The purification method of contaminated soil including the process of inject | pouring the nutrient for contaminated soil purification in any one of Claims 1-3 into soil. The nutrient for purifying contaminated soil according to any one of claims 1 to 3 , comprising a step of mixing and homogenizing an oily phase containing vegetable oil and / or a processed oil and fat of the oil and fat as a raw material oil and an aqueous phase. Manufacturing method.

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