JP2000354877A - Apparatus and method for decomposing organochlorine compound - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an apparatus for more rapidly and safely decomposing a voltage organochlorine compd. in an aq. medium. SOLUTION: This apparatus is provided with a means for infiltrating an aq. medium containing a voltage organochlorine compd. in a porous body 2, a chamber 9 for mixing the volatile organochlorine compd. volatilized from the porous body 2 in which the aq. medium is infiltrated with chlorine gas and the light irradiation means to the chamber 9. The light irradiation means can emit light with a wavenegth of 300-450 mm.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an apparatus for decomposing volatile organic chlorine compounds.

[0002]

2. Description of the Related Art Various volatile organic chlorine compounds have been used in the development of industrial technology, and their disposal is a serious problem due to their chemical stability. In addition, environmental problems such as the use of used volatile organic chlorine compounds polluting the natural environment have occurred, and great efforts have been made to solve them. Typical volatile organic chlorine compounds are chlorinated aliphatic hydrocarbons such as trichloroethylene and tetrachloroethylene, and a technique for economically and efficiently decomposing these leaked in wastewater or into the natural environment is desired.

[0003] Such volatile organic chlorine compound decomposition treatment includes incineration, thermal decomposition, photolysis, oxidative decomposition, reductive decomposition,
Methods such as catalysts and microbial degradation are known.
For example, the method of burning activated carbon to which a volatile organic chlorine compound has been adsorbed is the simplest treatment method. Further, in the thermal decomposition method, the generation of a toxic compound can be suppressed by controlling the temperature. However, since high-temperature treatment requires a large amount of energy, cost reduction is an issue.

[0004] Examples of using an oxidizing agent or a catalyst include:
A method of decomposing with ozone (JP-A-03-38297) and a method of irradiating ultraviolet rays in the presence of hydrogen peroxide (JP-A-63-21829)
3) Alternatively, a method of oxidative decomposition with hydrogen peroxide or an iron salt (JP-A-60-261590) is known. A method of decomposing volatile organic chlorine compounds in situ using hydrogen peroxide or hypochlorous acid as an oxidizing agent has also been disclosed (US Pat.
25008, 5616142). A decomposition method combining sodium hypochlorite and ultraviolet irradiation has also been proposed (JP-A-05-269374, US Pat. No. 5,558,271). There is also known a method in which a photocatalyst such as titanium oxide is irradiated with light to decompose a volatile organic chlorine compound under alkaline conditions (JP-A-07-14413).
7).

In addition to these methods, a method of irradiating a vaporized volatile organic chlorine compound with ultraviolet rays or a laser (Japanese Patent Laid-Open No.
43351, JP-A-06-262035), a method of performing oxidative decomposition using a platinum-based oxide (JP-A-06-31135), and a decomposition method using iron powder (JP-A-08-257570).

[0006] Several methods are known for efficiently separating or decomposing volatile pollutants in wastewater or groundwater. For example, a method of disposing a vane body made of a porous body in a pipe, bringing a liquid passing through the vane body into contact with a gas passing through the pipe, and moving volatile contaminants in the liquid to a gas (Japanese Patent Laid-Open No. 05-2005). 096144) and a method of decomposing volatile contaminants such as microorganisms by fixing them to a porous body, disposing them in a reactor and decomposing them (JP 08-024893, JP 09-266784, JP 10 -084947, U.S. Pat.
and so on. In addition, a method has been proposed in which a photocatalyst such as titanium oxide is used as a porous body, and a pollutant in groundwater is decomposed while irradiating the porous body (US Pat. No. 5,682,449).

[0007]

As described above, many methods for decomposing volatile organic chlorine compounds in wastewater and groundwater have been proposed, but from a practical viewpoint, a lower cost and safer treatment method is desired. ing. Specifically, it is an object of the present invention to provide an apparatus and a method that require less energy and materials for decomposition, have a high decomposition reaction rate, and can achieve processing that has little effect on the environment.

[0008]

The inventors of the present invention have conducted studies for the purpose of achieving the above-mentioned objects, and as a result, the present inventors have vaporized a volatile organic chlorine compound from an aqueous medium, and then vaporized this compound under irradiation with chlorine gas and light. It has been found that the volatile organic chlorine compound can be decomposed very efficiently by contacting with the above, and the present invention has been accomplished.

That is, a decomposition apparatus according to one embodiment of the present invention is a decomposition apparatus for a volatile organic chlorine compound in an aqueous medium, wherein (i) an aqueous medium containing a volatile organic chlorine compound in a porous body. Means for infiltrating; (ii) a chamber for mixing the volatile organic chlorine compound volatilized from the porous material impregnated with the aqueous medium with chlorine gas; and (ii)
i) means for irradiating the chamber with light.

The method for decomposing a volatile organic chlorine compound in an aqueous medium according to one embodiment of the present invention comprises: (i) impregnating an aqueous medium containing the volatile organic chlorine compound into a porous body;
Evaporating the volatile organic chlorine compound from the porous body; (ii) mixing the volatile organic chlorine compound volatilized from the porous body with chlorine gas; and (iii) the volatile organic chlorine compound And a step of irradiating a mixed gas of chlorine and chlorine gas with light to decompose the volatile organic chlorine compound.

Japanese Patent Application Laid-Open No. 08-281271 discloses a technique for decomposing a dye in a dyeing wastewater in an electrolytic cell by hypochlorous acid and / or hypochlorite ions generated by electrolysis. In addition, magazine "Water Treatment Technology" Vol.37, No.5 (1996)
Page 33 describes the treatment of dyeing wastewater using electrochemical reactions. However, there is no description in these patent publications or magazines suggesting that an aqueous medium containing a volatile organic chlorine compound can be decomposed. Further, there is no description about promoting a decomposition reaction by light irradiation.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A decomposition apparatus according to one embodiment of the present invention will be described below. FIG. 1 is a sectional view of a disassembly apparatus having a cylindrical outer shape. The decomposition device 1
It has a chamber (chamber) 9 and a second chamber 101, and the first chamber and the second chamber are separated by the porous body 2. Reference numeral 7 denotes an inlet for supplying an aqueous medium containing a volatile organic chlorine compound to the second chamber 101, and reference numeral 8 denotes an outlet for discharging the aqueous medium introduced into the second chamber 101. Also 5
Is an inlet for introducing chlorine gas into the first chamber 9;
Is an outlet for discharging gas from the first chamber. Reference numeral 3 denotes a stirring blade disposed in the first chamber, and reference numeral 4 denotes a light source disposed in the first chamber.

The aqueous medium introduced into the second chamber 101 penetrates the porous body 2, and the volatile organic chlorine compound is vaporized from the porous body 2 and enters the first chamber. Here, while the chlorine gas introduced into the first chamber from the inlet 5 and the vaporized volatile organic chlorine compound are stirred by a stirring blade, the light source 4 is turned on to irradiate light to decompose the volatile organic chlorine compound. . After the decomposition, excess chlorine gas and decomposition products are discharged from the outlet 6, and an aqueous medium having a reduced volatile organic chlorine compound concentration is discharged from the outlet 8.

The aqueous medium that can be treated by such an apparatus includes, for example, factory wastewater and groundwater containing a volatile organic chlorine compound. Chlorinated aliphatic hydrocarbons are mainly used as volatile organic chlorine compounds.Specifically, chlorinated ethylene such as vinyl chloride, 1,1-dichloroethylene, cis-dichloroethylene, trans-dichloroethylene, trichloroethylene, tetrachloroethylene, etc. And chlorinated methane such as chloromethane, dichloromethane and chloroform.
These volatile organic chlorine compounds may be contained alone in the aqueous medium, or two or more compounds may coexist. The concentration of the volatile organic chlorine compound in the aqueous medium can be processed from the environmental standard value to the concentration of the saturated aqueous solution for the compound for which the environmental standard value is set, and the environmental standard value is provided. For compounds that do not have a biotoxicity, they can be treated from a concentration that is not biologically toxic to a concentration of a saturated aqueous solution.

In the decomposition treatment, the irradiation light may be, for example, 30
Light having a wavelength of 0 to 450 nm may be used. The light irradiation intensity is, for example, 0 for a light source having a peak at a wavelength of 365 nm.
Decomposition proceeds at 1 mW / cm ² (measured between 300 nm and 400 nm),
If mW / cm ² or more, the light intensity is practically sufficient. Such light sources include artificial light sources such as mercury lamps, black lights, color fluorescent lamps, light-emitting diodes, and electroluminescent devices, as well as sunlight if they can be used stably. By introducing light from a light source into an optical waveguide such as an optical fiber and guiding the light to a decomposition device, the light source and the decomposition device can be separated. In addition, if a leaky optical fiber is used, light can be emitted in a linear or planar manner, so that the decomposition efficiency in the decomposition device can be further improved.

As the chlorine used for the decomposition, commercially available chlorine gas can be used. As a method for supplying chlorine gas more safely, for example, there is a method in which functional water is brought into contact with a gas, the chlorine gas is vaporized from the functional water, and the chlorine gas is used. This functional water refers to acidic water obtained on the anode side by dissolving an electrolyte such as sodium chloride or potassium chloride in water and electrolyzing the water with a pair of electrodes. Desirable properties of the functional water include a hydrogen ion concentration (pH value) of 1 to 4, a redox potential of 80 when the working electrode is a platinum electrode, and the reference electrode is silver-silver chloride.
0-1500 mV and chlorine concentration 5-150 mg / l. Further, an aqueous solution having the same properties as the functional water may be prepared chemically. For example, addition of hydrochloric acid to sodium hypochlorite has the same function as functional water.

In a volatile organic chlorine compound decomposer, it is desired to treat a large amount of the compound per unit time.
A large decomposition reaction rate is required. Therefore, the concentration of the volatile organic chlorine compound in the aqueous medium may be increased by a concentration operation or the like, or the volatile organic chlorine compound may be vaporized and reacted in the gas phase. In the decomposition apparatus of the present invention, since the decomposition reaction is considered to proceed mainly in the gas phase, it is important to increase the vaporization rate so that the vaporization of the volatile organic chlorine compound from the aqueous medium does not become reaction-limited. The simplest method is to use a porous material capable of increasing the area of the gas-liquid interface in the flow path of the aqueous medium to promote gas-liquid contact and increase the vaporization rate. Many organic or inorganic materials can be used for the porous body. For example, porous materials such as Teflon, polystyrene, polyethylene, polyurethane, vinyl chloride, urea resin, phenolic resin, rubber, etc., porous materials such as perlite, vermiculite, foam glass, or asbestos, rock wool, glass wool, ceramic fiber, animals and plants By filling a fibrous material such as fiber or carbonaceous fiber into the decomposition device, the same effect as that of the porous body can be exhibited. Further, inorganic materials such as alumina, calcium silicate, magnesium carbonate, and diatomaceous earth may be fired to form a porous body.

The simplest means for flowing an aqueous medium or functional water down the porous body is a method utilizing a hydrostatic pressure difference, that is, a method of dropping water by its own weight. This method can be used when the porosity of the porous body is large and the porosity is continuously connected.However, if the pore diameter of the porosity is reduced to increase the specific surface area of the porous body, the pressure loss increases and the weight of the porosity increases. It is difficult to flow down the river. In such a case, the liquid may be forcibly sent by a pump. In either case, it is desirable to control the liquid sending rate so that the volatile organic chlorine compound can be sufficiently vaporized.

The vaporized volatile organic chlorine compounds can be efficiently decomposed by sufficiently mixing with chlorine (including those derived from functional water and hypochlorous acid) and irradiating with light. Unless the mixture can be sufficiently mixed by natural diffusion, it is desirable to provide a means for mixing both in the decomposition device. Specific examples include stirring the mixed gas with a stirring blade, and attaching a baffle plate to the gas flow path to promote mixing.

FIG. 2 is a plan view of the configuration of FIG. The decomposition apparatus includes a decomposition chamber 9, a porous body 10, and a leaky optical fiber 11. Chlorine is introduced from the inlet 12, passes through the decomposition chamber 9, and is discharged from the outlet 13. The aqueous medium containing the volatile organic chlorine compound is directly introduced into the porous body 10 through the inlet 14 and discharged through the outlet 15.
The volatile organic chlorine compound vaporized from the aqueous medium in the process of flowing down the porous body 10 diffuses into the decomposition chamber 9 and is mixed with chlorine. Then, the mixed gas in the decomposition chamber 9 is irradiated with light from the leak type optical fiber 11, and as a result, the volatile organic chlorine compound is decomposed.

FIG. 3 is a schematic perspective view of a decomposition apparatus using the above-described functional water as a chlorine gas generation source, and FIG.
It is a line sectional view.

Decomposing device 16 having a cylindrical outer shape
Is separated so that the functional water and the aqueous medium are not mixed.
It comprises one porous body (a first porous body 17 and a second porous body 18), a stirring blade 19, and a light source 20. The aqueous medium containing the volatile organic chlorine compound is directly introduced into the first porous body 17 from the inlet 21 and is discharged from the outlet 22 while being in contact with the first porous body 17.
Further, the functional water is directly introduced into the second porous body from the inlet 23, and is discharged from the outlet 24 while being in contact with the second porous body 18. In the course of the aqueous medium flowing down the first porous body 17, volatile organic chlorine compounds are vaporized from the first porous body, and functional water is removed from the second porous body 18.
Chlorine gas is vaporized from the second porous body in the process of flowing down, and the inside of the chamber 9 is filled with the volatile organic chlorine compound and chlorine gas. The chlorine gas and the volatile organic chlorine compound in the chamber 9 are mixed in the decomposer, and the stirring blade 19 is appropriately rotated in order to promote the mixing of the two, and the light source 20 is turned on to irradiate the light to emit light. The decomposition of the volatile organic chlorine compound is performed. After decomposition, excess chlorine and decomposition products are obtained from the outlet 25, and a purified aqueous medium is obtained from the outlet 22.

FIG. 5 is a plan view of the configuration of FIG. The decomposition device includes a decomposition chamber 26, two porous bodies (a first porous body 27 and a second porous body 28), and a leaky optical fiber 29. The aqueous medium is directly introduced into the porous body 27 from the inlet 30 and discharged from the outlet 31. In addition, functional water is introduced directly into the porous body 28 through the inlet 32, and the outlet 3
It is discharged from 3. Since the porous bodies 27 and 28 are in contact with the decomposition chamber 26 directly or through the gap of the leaky optical fiber 29, the volatile organic chlorine compounds and chlorine gas vaporized from the porous bodies 27 and 28 are mixed in the decomposition chamber 26. Is done. Further, the decomposition chamber 26 is irradiated with light by the leak type optical fiber 29 to perform a decomposition reaction. After the decomposition, excess chlorine and decomposition products are obtained from the outlet 34, and the purified aqueous medium is obtained from the outlet 31.

Although various embodiments according to the present invention have been specifically described above, it is needless to say that the present invention is not limited to these embodiments.

Hereinafter, the present invention will be described in detail with reference to Examples.
They do not limit the invention in any way.

Example 1 <Explanation of Apparatus Used in Experiment> An experimental apparatus shown in FIG. 1 was manufactured and provided for an example. First, an alumina porous cylindrical tube 2 (inner diameter 40 mm, outer diameter 60 mm, length 500 mm) was replaced with a stainless steel cylindrical tube 1 (inner diameter 80 mm, outer diameter 100 mm, length 500 mm).
mm, manufactured by NGK Insulators, Ltd., FA-2). next,
Stirring impeller 3 (outer diameter of blade 15 mm) inside porous cylindrical tube 2
And light source 4 (black light, manufactured by Toshiba Lighting & Technology Corporation)
6 W x 2). Finally, both ends of the cylindrical tube 1 were closed with stainless steel flanges having inlets 5 and 7 and outlets 6 and 8 to assemble a disassembling apparatus.

<Decomposition of Volatile Organic Chlorine Compounds> [0027] Volatility of 1,1-dichloroethylene, cis-dichloroethylene, trans-dichloroethylene, trichloroethylene, tetrachloroethylene, and dichloromethane is adjusted so that the concentration of each is 5 ppm. The soluble organic chlorine compound was dissolved. This solution was flowed from the inlet 7 at a flow rate of 10 ml / min. Further, chlorine (supplied from a chlorine cylinder) and air were mixed so that the chlorine concentration became 500 ppmV, and this was introduced from the inlet 5 at a flow rate of 10 ml / min. Stirring blade 3 at 120
The light source 4 was turned on while rotating to accelerate gas mixing. The concentration of the volatile organochlorine compound in the gas discharged from the outlet 6 and the concentration of the volatile organochlorine compound in the solution discharged from the outlet 8 were each determined by gas chromatography with an electron capture detector (directly). The sample was injected, and after extracting with n-hexane, the sample was injected and measured by GC-14B manufactured by Shimadzu Corporation.
As a result, the concentration of any volatile organic chlorine compounds in the gas was 0.05 ppmV or less. In addition, the concentration of any volatile organic chlorine compound in the solution was 0.1 ppm or less, indicating that the volatile organic chlorine compound can be efficiently decomposed by this decomposing device.

Next, the chlorine concentration was changed in the range of 5 ppmV to 1000 ppmV, and the concentration of the volatile organic chlorine compound after decomposition was measured. The initial concentration of the volatile organic chlorine compound was determined at any chlorine concentration. (5 ppm), confirming that it can be decomposed by this decomposer.

Comparative Example 1 Example 1 was repeated except that only air was introduced from the inlet 5.
An experiment was performed in the same manner as described above. As a result, the concentration of any volatile organochlorine compound in the gas was 100 ppmV or more, and the concentration of any volatile organochlorine compound in the solution was 3 ppm or more. From this, it was found that the decomposition of the volatile organic chlorine compound did not occur unless chlorine was introduced.

Example 2 An experimental apparatus shown in FIG. 2 was prepared and used in Examples. First, a PMMA decomposition chamber 9 (width 100 mm, length 30)
0 mm, thickness 15 mm) and alumina porous plate 10 (width 100
mm, length 300 mm, thickness 30 mm, NGK Insulators, FP
-6). In addition, the porous plate 10 was vapor-deposited with aluminum except for the contact surface with the decomposition chamber 9 to prevent leakage of the aqueous medium. Further, the light of the black light used in Example 1 was leaked to the optical fiber 11 (Sumitomo).
3M, 3M light fiber side light high brightness type) and attached to the side of the decomposition chamber 9.
Further, the same aqueous medium containing chlorine and a volatile organic chlorine compound as in Example 1 was flowed from the inlets 12 and 14, respectively, and the concentration of the volatile organic chlorine compound discharged from the outlets 13 and 15 was determined as in Example 1. Measured similarly. As a result, the concentration of any chlorinated aliphatic hydrocarbon in the gas was 0.1 ppmV or less. Further, the concentration of any chlorinated aliphatic hydrocarbons in the solution was 2 ppm or less, and it was found that the chlorinated aliphatic hydrocarbons could be efficiently decomposed by this decomposition device.

Next, the concentration of the volatile organic chlorine compound after decomposition was measured by changing the irradiation light intensity from the leaky optical fiber in the range of 10 μW / cm ² to 10 mW / cm ² . The light intensity was also lower than the initial concentration (5 ppm) of the volatile organic chlorine compound, and it was confirmed that it could be decomposed by this decomposition device.

Example 3 In Example 1, a porous tube made of Teflon (Teflon filter, average pore size 25) was used instead of the porous tube made of alumina.
(μm, 0.13 mm thickness). Using this apparatus, the decomposition of volatile organic chlorine compounds was carried out in the same manner as in Example 1. As a result, the concentration of any volatile organic chlorine compounds in the gas was 0.7 ppmV or less. Also, the concentration of any volatile organic chlorine compounds in the solution was 1.
It was 5 ppm or less, indicating that volatile organic chlorine compounds could be efficiently decomposed by this decomposer.

Example 4 <Explanation of Apparatus Used in Experiment> An experimental apparatus shown in FIG. 3 was manufactured and provided for an example. First, an alumina porous cylindrical tube (inner diameter 40 mm, outer diameter 60 mm, length 500 mm, manufactured by NGK Insulators, Ltd., FA-2) is vertically divided into two equal parts (17 and 18), Stainless steel plate (width 10 mm, length 500 mm,
It was again cylindrical with a thickness of 2 mm). Aluminum was vapor-deposited only on the outer part of the cylinder to prevent the flowing solution from leaking out. A stirring blade 19 and a light source 20 similar to those of the first embodiment are installed in the inside, and inlets 21 and 2 are provided.
3. The cylindrical end was closed with a stainless steel flange having outlets 22 and 24 to 25 to prepare a disassembly apparatus.

<Decomposition of Chlorinated Aliphatic Hydrocarbons>
Similarly, each was dissolved in pure water so that the concentration of the volatile organic chlorine compound was 5 ppm. This solution was flowed from the inlet 21 at a flow rate of 10 ml / min.

Next, functional water was prepared using a strongly acidic functional water generator (trade name: strong electrolytic water generator (Model FW-200), manufactured by Amano Corporation). Using this device, the electrolyte concentration and electrolysis time of the water to be electrolyzed are variously changed, and the pH and redox potential of the functional water obtained on the anode side are measured with a pH meter (Toko Chemical Laboratory, TCX-90i and KP900-2N) and conductivity meter (Toko Chemical Laboratory Co., Ltd., TCX-90i and K
M900-2N), and the chlorine concentration was further measured with a chlorine test paper (Advantech). As a result, the pH of this functional water is 1-4, the oxidation-reduction potential is 800-1500 mV, and the chlorine concentration depends on the concentration of sodium chloride as an electrolyte (standard concentration is 1000 mg / l), electrolysis current value and electrolysis time. Is 5-150 mg / l
Changed to Therefore, in this embodiment, pH 2.6 as functional water,
Functional water having an oxidation-reduction potential of 1000 mV and a chlorine concentration of 54 mg / l was prepared. This functional water was obtained by setting the electrolyte (sodium chloride) concentration to 1000 mg / l and the electrolysis time to 5 minutes. This functional water was supplied from the inlet 23 at a flow rate of 10 ml / min.

Next, the stirring blade 19 is rotated, the light source 20 is turned on to perform decomposition, and the concentration of the volatile organic chlorine compound in the gas discharged from the outlet 25, and further discharged from the outlets 22 and 24. The concentration of the volatile organic chlorine compound in each solution was measured. As a result, the concentration of any volatile organochlorine compounds in the gas was 0.
It was less than 1 ppmV. In addition, the concentration of any volatile organic chlorine compound in the solution was 0.4 ppm or less, and it was found that the volatile organic chlorine compound can be efficiently decomposed by this decomposition device.

Further, the electrolysis conditions during the production of the functional water were changed so that the pH was 1-4, the oxidation-reduction potential was 800 mV-1500 mV, and the chlorine concentration was 5
When functional water of mg / l to 150 mg / l was prepared and subjected to decomposition, the concentration of volatile organic chlorine compounds was lower than the initial concentration (5 ppm) in all functional waters. I confirmed that I can do it.

Example 5 An experimental apparatus shown in FIG. 4 was manufactured and provided for an example. First, the decomposition chamber 26 and the porous plate 27 were bonded in the same manner as in Example 2. In addition, the leakage type optical fiber 2
The window surface of the disassembling chamber 26 in contact with 9 was removed, and the leaky optical fiber 29 was also set in a frame made of PMMA without the window surface. A porous plate 28 is provided on the frame side of the leaky optical fiber 29 so as to sandwich the decomposition chamber 26 and the leaky optical fiber 29 in a sandwich shape. Solution was not leaked out.

Next, in the same manner as in Example 1, each was dissolved in pure water so that the concentration of the volatile organic chlorine compound became 5 ppm, and the solutions were flowed through the inlet 30 at a flow rate of 10 ml / min. did. In addition, 0.01 wt% of sodium hypochlorite
Hydrochloric acid (10 mM) solution containing
It flowed at a flow rate of 10 ml per minute from 2. The decomposition chamber 26 is decomposed by irradiating sunlight to the decomposition chamber 26 through the leaky optical fiber 29, the concentration of the volatile organic chlorine compound in the gas discharged from the outlet 34, and the concentration in the solution discharged from the outlets 31 and 33. The concentrations of the volatile organic chlorine compounds were measured. As a result, the concentration of any volatile organic chlorine compounds in the gas was 0.05 ppmV or less. In addition, the concentration of any volatile organic chlorine compound in the solution was 0.1 ppm or less, indicating that the volatile organic chlorine compound can be efficiently decomposed by this decomposing device.

Further, the concentration of hypochlorite and the concentration of hydrochloric acid were changed to prepare functional water having a pH of 1 to 4, a redox potential of 800 mV to 1500 mV, and a chlorine concentration of 5 mg / l to 150 mg / l. When subjected to decomposition, in each case, the concentration was lower than the initial concentration (5 ppm) of the volatile organic chlorine compound, and it was confirmed that the decomposition was possible by the present decomposition apparatus.

[0041]

According to the present invention, a volatile organic chlorine compound,
In particular, it has become possible to efficiently decompose and purify wastewater and groundwater contaminated with chlorinated aliphatic hydrocarbons such as tetrachloroethylene and trichloroethylene.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of a decomposition apparatus according to one embodiment of the present invention.

FIG. 2 is a schematic cross-sectional view of a decomposition apparatus according to another embodiment of the present invention.

FIG. 3 is a schematic perspective view of a disassembling apparatus according to still another embodiment of the present invention.

FIG. 4 is a sectional view taken along the line AA of the disassembling apparatus of FIG. 3;

FIG. 5 is a schematic perspective view of a disassembling apparatus according to still another embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Decomposition apparatus 2 Porous body 3 Stirring blade 4 Light source 5 Inlet 6 Outlet 7 Inlet 8 Outlet 9 Chamber 10 Porous body 11 Leakage type optical fiber 12 Inlet 13 Outlet 14 Inlet 15 Outlet 16 Decomposition apparatus 17 Porous body 18 Porous body 19 Stirring blade 20 Light source 21 Inlet 22 Outlet 23 Inlet 24 Outlet 25 Outlet 26 Chamber 27 Porous body 28 Porous body 29 Leaky optical fiber 30 Inlet 31 Outlet 32 Inlet 33 Outlet 34 Outlet 101 Outlet 101 Second chamber

Claims (37)

[Claims] 1. A device for decomposing a volatile organic chlorine compound in an aqueous medium, comprising: (i) means for permeating an aqueous medium containing a volatile organic chlorine compound into a porous body; (ii) permeation of the aqueous medium A chamber for mixing the volatile organic chlorine compound volatilized from the porous body and chlorine gas; and (i)
ii) a decomposition apparatus comprising: a light irradiating unit for irradiating the chamber. 2. The decomposition apparatus according to claim 1, wherein the means for permeating a volatile organic chlorine compound into the porous body is a means for directly supplying the aqueous medium to the porous body. 3. The means for directly supplying an aqueous medium to the porous body is disposed at a position where the aqueous medium supplied to the porous body flows down the porous body by gravity. The disassembly apparatus according to any one of the preceding claims. 4. A storage chamber for said aqueous medium, wherein said means for permeating an aqueous medium containing a volatile organic chlorine compound into said porous body is disposed in said chamber through a wall of said porous body, and said storage means. And means for supplying said aqueous medium to the chamber.
The disassembly apparatus according to any one of the preceding claims. 5. The decomposition apparatus according to claim 4, further comprising means for supplying the aqueous medium to the storage space. 6. The decomposition apparatus according to claim 1, wherein the aqueous medium is wastewater or groundwater. 7. The decomposition apparatus according to claim 1, wherein the volatile organic chlorine compound is a chlorinated aliphatic hydrocarbon compound. 8. The method according to claim 3, wherein the chlorinated aliphatic hydrocarbon is at least one selected from the group consisting of 1,1-dichloroethylene, cis-dichloroethylene, trans-dichloroethylene, trichloroethylene, tetrachloroethylene, and dichloromethane. Disassembly device. 9. The light irradiating means has a wavelength of 300 nm to 450 nm.
The decomposer according to claim 1, which is capable of emitting light in a wavelength range of: 10. The light irradiating means has a light intensity of 10 μW / cm ^2.
Decomposing apparatus according to claim 1 is capable emitting light at ~10 mW / cm ^2. 11. The concentration of the chlorine gas is 5 ppmV to 1000 ppm.
The decomposition device according to claim 1, wherein V is V. 12. The decomposition apparatus according to claim 1, wherein the porous body is a ceramic. 13. The decomposition apparatus according to claim 12, wherein the ceramic is alumina. 14. The decomposition apparatus according to claim 1, wherein the porous body is a polymer. 15. The polymer according to claim 14, wherein said polymer is Teflon.
A disassembly apparatus according to claim 1. 16. The decomposition apparatus according to claim 1, wherein the shape of the porous body is cylindrical or flat. 17. The decomposition apparatus according to claim 1, further comprising a stirring means in said chamber. 18. The stirring means according to claim 17, wherein said stirring means is a stirring blade.
The disassembly apparatus according to any one of the preceding claims. 19. The decomposition apparatus according to claim 1, wherein the light irradiation means is at least one selected from a black light, a light emitting diode, and an electroluminescent element. 20. The decomposition apparatus according to claim 1, wherein said decomposition apparatus further comprises means for generating said chlorine gas. 21. The decomposition apparatus according to claim 20, wherein said means for generating chlorine gas comprises a second porous body and a means for permeating functional water into said second porous body. 22. The decomposition apparatus according to claim 21, wherein the means for permeating the functional water into the second porous body includes a means for directly supplying the functional water to the second porous body. 23. A means for directly supplying functional water to the second porous body, wherein the functional water supplied to the second porous body flows down the second porous body by gravity along the second porous body. 23. The disassembly device according to claim 22, wherein the disassembly device is disposed at a position where the disassembly is performed. 24. The means for permeating functional water into the second porous body includes a functional water storage chamber disposed adjacent to the chamber through a wall of the second porous body. Item 2
3. The disassembly apparatus according to 3. 25. The functional water has a hydrogen ion concentration (pH value).
24. The method according to claim 21, wherein the redox potential (working electrode: platinum electrode, reference electrode: silver-silver chloride electrode) is 800 mV to 1500 mV, and the chlorine concentration is 5 mg / l to 150 mg / l. The disassembly apparatus according to any one of the preceding claims. 26. The decomposition apparatus according to claim 25, wherein the functional water is acidic water generated near an anode by electrolysis of water containing an electrolyte. 27. The decomposition apparatus according to claim 26, wherein the electrolyte is at least one of sodium chloride and potassium chloride. 28. The decomposition apparatus according to claim 21, wherein the functional water is an aqueous solution of hypochlorite. 29. The decomposition apparatus according to claim 28, wherein the hypochlorite is at least one of sodium hypochlorite and potassium hypochlorite. 30. The decomposition apparatus according to claim 28, wherein the aqueous solution further contains an inorganic acid or an organic acid. 31. The inorganic acid or the organic acid is at least one selected from hydrochloric acid, hydrofluoric acid, oxalic acid, sulfuric acid, phosphoric acid, boric acid, acetic acid, formic acid, malic acid, and citric acid. A disassembly apparatus according to claim 1. 32. The decomposition apparatus according to claim 21, wherein the second porous body is a ceramic. 33. The decomposition apparatus according to claim 32, wherein the ceramic is alumina. 34. The decomposition device according to claim 21, wherein the second porous body is a polymer. 35. The polymer according to claim 34, wherein the polymer is Teflon.
A disassembly apparatus according to claim 1. 36. The decomposition apparatus according to claim 32, wherein the shape of the second porous body is cylindrical or flat. 37. A method for decomposing a volatile organic chlorine compound in an aqueous medium, comprising the steps of: (i) impregnating an aqueous medium containing a volatile organic chlorine compound into a porous body; (Ii) a step of mixing the volatile organic chlorine compound volatilized from the porous body with chlorine gas; and (iii) a gas mixture of the volatile organic chlorine compound and chlorine gas. Decomposing the volatile organic chlorine compound by irradiating the volatile organic chlorine compound with light.