JP2003311231A - Cleaning method and cleaning apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cleaning method for removing a toxic substance intruding into a minute gap on the surface of the object to be treated and sticking there. <P>SOLUTION: This cleaning method comprises a step to immerse the object 1 to be treated in a cleaning liquid 2 of dimethylsulfoxide (DMSO) to make the liquid 2 intrude into the minute gap, so that the toxic substance stuck to the minute gap can be removed. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cleaning method and apparatus for removing harmful substances adhering to fine gaps on the surface of an object to be treated, and more particularly to a rusted transformer or capacitor contaminated with PCB. It is effective when applied when washing containers.

[0002]

2. Description of the Related Art In recent years, PCB (Polychlorinated bi
phenyl, polychlorinated biphenyl: a generic term for chlorinated isomers of biphenyl) is highly toxic and its manufacture and import are prohibited. Although this PCB was first manufactured in Japan around 1954, its adverse effects on the living body and environment became clear after the Kanemi Yusho incident.
In 2 years, there was a history of instructions to discontinue production and collection (duty of storage) by administrative guidance.

PCB has 1 to 1 chlorine in the biphenyl skeleton.
It has 0 substitutions, and theoretically there are 209 kinds of isomers depending on the number and position of the substituted chlorine.
About 100 or more isomers have been confirmed in CB products. In addition, the physical and chemical properties among these isomers, the in vivo stability, and the environmental dynamics are so diverse that the chemical analysis of PCB and the mode of environmental pollution are complicated at present. Further, PCB is one of the persistent organic pollutants, is not easily decomposed in the environment, is fat-soluble, has a high bioconcentration rate, and is semi-volatile, and is capable of being transferred through the atmosphere. In addition, it has been reported that it widely remains in the environment such as water and living things.

This PCB was an abandoned PC in 1997.
B, waste oil containing PCB, and PCB pollutants are designated as specially controlled wastes based on the law on waste treatment and cleaning. In addition, wood chips and fiber scraps were added as PCB pollutants in 1997. Designated.

There are high-voltage transformers, high-voltage capacitors, low-voltage transformers / capacitors, pole transformers as electric equipment to be treated with PCBs, and as waste PCBs, those used as a heat medium used as insulating oil, In addition, there are kerosene and the like used for cleaning these, and as the pressure-sensitive waste paper, there is capsule oil used for carbonless paper, and further, use of these PCBs or replacement of heat medium, regeneration of insulating oil, leakage. There are PCB pollutants such as activated carbon used in the purification of the above, the treatment of PCB-containing substances, waste white clay, waste waste, work clothes and the like. Currently, these are strictly stored, but urgent PCB treatment is desired.

In recent years, various techniques for processing PCBs used in such transformers have been developed.
For example, the technique described in Japanese Patent Laid-Open No. 9-79531 is known. FIG. 11 shows a flowchart of the PCB processing method according to the above proposal.

As shown in FIG. 11, first, oil is drained from the transformer in which the PCB is enclosed (S901), and the PCB adhering to the inside is removed by solvent cleaning (S902), and then collected (S903). . The solvent after washing is decomposed with the oil extracted from the transformer (S
904), it is rendered harmless.

Next, the oil-removed transformer is dried, and the PCB is evaporated by heating at high temperature and normal pressure in the absence of oxygen (S9
05), prevent the PCB from scattering. Then, the dried transformer is disassembled (S906), and the case and the transformer core are separated. The case is provided as a scrap source for an electric furnace or a converter (S907). On the other hand, the transformer core has its copper coil cut by a mobile shear or the like to be separated into a coil wire and an iron core (S908).

The separated iron core is melted in a melting furnace and recovered (S909). Further, the separated copper coil and the organic matter such as paper attached to the copper coil are melted in the induction heating furnace (S910). Then, the molten copper is recovered, and the PCB gas generated in each melting furnace is detoxified by high-temperature thermal decomposition at 1200 ° C. (S911).

[0010]

In the conventional PCB processing method as described above, the PCB is decomposed by melting various metallic members (objects to be processed), so that the equipment becomes large in scale. Not only that, but a large amount of heat energy is required, and the initial cost and running cost are high.

Therefore, for example, by cleaning the object to be processed with a cleaning agent such as hexane or toluene and transferring the PCB adhering to the surface of the object to be processed to a cleaning liquid,
It is considered to treat the object to be treated. However,
Depending on the condition of the object to be processed, it may be very difficult to sufficiently remove the PCB by washing.

As a result of investigating the cause of this, as shown in FIG. 12, when there is a fine gap 803 due to rust or the like in the plating 802 on the surface of the base material 801, the molecules of the PCB enter the gap 803 and are adsorbed. Therefore, it was found that the molecules of the PCB adsorbed and adsorbed could not be sufficiently removed from the gap 803 even if washed with a cleaning agent such as hexane or toluene.

Such a problem is not limited to the case of cleaning a transformer contaminated with a PCB or a rusted container of a capacitor, etc., and removes harmful substances that have entered and adsorbed into minute gaps on the surface of the object to be treated. If it does, it can happen in the same manner as the above case.

In view of the above, the present invention is capable of sufficiently cleaning and removing harmful substances even when the harmful substances enter and adsorb into the minute gaps on the surface of the object to be treated. It is an object of the present invention to provide a cleaning method and an apparatus for cleaning the same.

[0015]

A first invention for solving the above-mentioned problems is a cleaning method for removing harmful substances adhering to an object to be treated, which is dimethyl sulfoxide (DMSO).
The cleaning method is characterized in that the harmful substance is washed away by immersing the object to be treated in a cleaning liquid.

According to a second aspect of the present invention, in the first aspect of the present invention, the cleaned object is heated in an inert gas atmosphere under a reduced pressure environment to dry the object to be cleaned. There is a characteristic cleaning method.

A third aspect of the present invention is a cleaning method for removing harmful substances adhering to the inside of an object to be treated, which comprises supplying a dimethyl sulfoxide (DMSO) cleaning solution into the object to be treated to clean the inside. In the cleaning method, the harmful substance is removed by cleaning.

A fourth invention is a cleaning method according to the third invention, characterized in that the cleaning is carried out in a saturated atmosphere of a dimethyl sulfoxide (DMSO) cleaning liquid.

A fifth aspect of the present invention is the cleaning method according to the first or third aspect, wherein the harmful substance is at least one of PCB, waste paint, waste fuel, and harmful chemicals.

A sixth aspect of the present invention is the cleaning method according to the first or third aspect of the present invention, wherein the object to be treated is an inorganic member of a transformer or capacitor containing PCB.

A seventh aspect of the present invention is the cleaning method according to the first or third aspect, wherein the member is a rusted container.

An eighth invention is a cleaning apparatus for removing harmful substances adhering to an object to be processed, wherein the object to be processed is put inside and a dimethyl sulfoxide (DMSO) cleaning liquid is put inside. The cleaning device is characterized by being provided with.

A ninth aspect of the present invention is an invention of a cleaning device for removing harmful substances attached to an object to be treated, wherein a heating tank in which the object to be treated is put inside and the inside can be sealed, and an inside of the heating tank. The cleaning apparatus is provided with an environment adjusting means for making the environment any one of a vacuum environment and an inert gas atmosphere, and a heating means for heating the inside of the heating tank.

A tenth aspect of the present invention is the cleaning apparatus according to the eighth aspect, characterized in that the tank is provided with ultrasonic wave oscillating means.

An eleventh invention is, in the eighth invention, a heating tank in which the object to be treated can be put inside and the inside can be sealed, and an environment in which the inside of the heating tank is in a vacuum environment and an inert gas atmosphere. The cleaning apparatus is provided with an adjusting means and a heating means for heating the inside of the heating tank.

A twelfth aspect of the invention is an invention of a cleaning device for removing harmful substances adhering to fine gaps on the surface of an object to be treated, wherein a dimethyl sulfoxide (DMSO) cleaning liquid is supplied to the inside of the object to be treated. Cleaning liquid supply means,
Dimethyl sulfoxide (DM
SO) a dimethylsulfoxide (DMSO) cleaning liquid spraying means under a saturated atmosphere of steam, and a cleaning device.

A thirteenth invention is the invention according to the eighth or twelfth invention, wherein the harmful substance is PCB, waste paint, waste fuel,
The cleaning device is characterized by being at least one of harmful chemicals.

A fourteenth aspect of the present invention is the cleaning apparatus according to the eighth or twelfth aspect, wherein the object to be treated is an inorganic member of a transformer or capacitor containing PCB.

A fifteenth invention is the cleaning apparatus according to the eighth or twelfth invention, wherein the member is a rusted container.

[0030]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a cleaning method and an apparatus therefor according to the present invention will be described below with reference to the drawings, but the present invention is not limited to these embodiments.

[First Embodiment] The first embodiment of the cleaning method and apparatus according to the present invention will be described with reference to FIGS. FIG. 1 is a schematic configuration diagram of the cleaning device, and FIG. 2 is
Schematic configuration diagram of the transformer, FIG. 3 is a schematic configuration diagram of the capacitor, FIG. 4 is a schematic configuration diagram of the fluorescent lamp ballast, and FIG. 5 is a PC.
FIG. 6 is an explanatory diagram of the B treatment system, and FIG. 6 is an overall configuration diagram of the harmful substance treatment system.

The cleaning method of the present embodiment is a cleaning method for removing harmful substances adhering to fine gaps on the surface of an object to be treated, which is dimethyl sulfoxide (DMSO).
By immersing the object to be treated in a cleaning liquid, the cleaning liquid is allowed to enter the gap to clean and remove the harmful substance attached to the gap.

Here, the cleaned object is heated in a reduced pressure environment, an inert gas atmosphere, or a steam atmosphere to dry the object to be cleaned. You may

As a pre-cleaning treatment for the main cleaning, a rough cleaning may be performed with a cleaning agent such as hexane, toluene, a hydrocarbon-based (for example, C11 hydrocarbon) cleaning liquid, isopropanol (IPA) or the like.

<Processing Object> Examples of processing objects that can be cleaned by the cleaning method and apparatus according to the present invention include:
A transformer, a condenser, a fluorescent lamp ballast, etc. to which PCB is applied as the insulating oil can be mentioned. A schematic configuration of such a transformer, a condenser, and a fluorescent lamp ballast will be described with reference to FIGS.

As shown in FIG. 2, the transformer 10 has a structure in which a core 13 in which a coil 12 made of copper is wound around an iron core 11 is housed in a container 14 made of iron, and PCB oil is enclosed inside as insulating oil. It was done. Also, the coil 12
Is a structure in which an insulating paper is wrapped around a copper wire, and an insulator 18 is provided on the upper portion of the iron frame 17. The opening of the container 14 is sealed by the lid 19. A typical transformer has a capacity range of 5 to 100 kVA, and the present invention can process in all ranges.

Further, as shown in FIG.
Is filled in a container 25 in a state in which a plurality of elements 21 are bundled by a fixing band 23 via a press board 22 covered with insulating paper 24, and PCB oil is sealed inside from a sealing port 25a. It has been done. Note that FIG.
Inside, 27 is a ground terminal, 28 is a high voltage terminal, and 29 is an insulator. The element 21 is composed of aluminum foil, insulating paper, resin film, spacers, and the like. A typical capacitor has a capacity range of several to 500 kvar, and the present invention can process in all ranges.

Further, as shown in FIG. 4, the fluorescent lamp ballast 3
0 consists of a transformer 31 and a power factor improving capacitor 32, and the PCB oil 1 is used as insulating oil in the capacitor 32. Since this capacitor 32 has a small capacity and the amount of PCB oil 1 is small, it can be processed without pretreatment.

<Cleaning Device> Next, the cleaning device according to the present embodiment will be described with reference to FIG. As shown in Figure 1,
Above the cleaning tank 111, dimethyl sulfoxide (DM
A cleaning liquid supply device 112 which is a cleaning liquid supply means for supplying the (SO) cleaning liquid 2 into the cleaning tank 111 is provided. Inside the cleaning tank 111, a bracket 111a that supports the cleaning case 101 made of wire mesh is attached. An ultrasonic oscillator 113, which is an ultrasonic wave oscillating means for oscillating ultrasonic waves into the cleaning tank 111, is provided below the cleaning tank 111.
Is attached. Further, a discharge valve 114 for discharging the cleaning liquid 2 in the cleaning tank 111 to the outside is connected to the lower portion of the cleaning tank 111.

<Cleaning Method> Using the cleaning apparatus 100 as described above, the object 1 to be processed (PCB residual amount: PCB remaining on the surface and adsorbing and remaining in the minute gaps:
The case of cleaning about 10 mg / m ² ) will be described below with reference to FIG.

The object to be processed 1 is put in the cleaning casing 101, the cleaning casing 101 is put in the cleaning tank 111, and the bracket 11 is inserted.
When the ultrasonic oscillator 113 is operated after placing the object 1a on the substrate 1a and immersing the object 1 in the cleaning liquid 2.
Is ultrasonically cleaned in the cleaning liquid 2.

At this time, dimethyl sulfoxide (DMS
O) The cleaning liquid 2 is a PC attached to the surface of the object 1 to be processed.
The B oil is dissolved and removed from the surface, and at the same time, it penetrates into a fine gap such as rust formed on the surface of the object to be processed 1 and dissolves the PCB adsorbed in the gap to remove it from the gap. .

Because the cleaning liquid 2 has the structure shown in the following "Chemical formula 1" and has a high polarity and functions as an aprotic solvent having a high dissolving power, the rust and the like generated on the surface of the object to be treated 1 This is because it is possible to easily penetrate into fine gaps and to exhibit a high dissolving ability for PCB.

Further, in FIG. 10, dimethyl sulfoxide (D
MSO) Cleaning performance index and cleaning performance between cleaning solution and other cleaning solutions
The relationship with the carbon number (pieces) of the cleaning agent is shown. According to FIG.
Dimethyl sulfoxide (DMSO) is another cleaning solution (carbonization
Hydrogen-based cleaning agent ("NS-100: trade name. C₁₁H_{twenty four}, Charcoal
Hydrogen-based cleaning agent (“EM Clean”: trade name. C
₉H ₁₂, N-hexane (C₆H₁₄), Isopropyla
Lucor (IPA: C₃H₇OH), perchloroethyl
(C₂Cl_Four)) Etc. have a very high cleaning ability
Will be

[0045]

[Chemical 1]

For this reason, the number of atoms constituting the molecule is large (C ₆ or more) such as hexane and toluene, and remains on the object to be treated 1 as compared with the case of cleaning with a cleaning liquid having no polar group. The PCB concentration can be significantly reduced (about 1/200).

Further, since a solvent such as hexane dissolves while containing the oil contained other than PCB, a large amount of solvent is required to remove PCB. However, when a dimethylsulfoxide (DMSO) cleaning solution is used, Since only the aromatic halide is positively dissolved, the dissolved amount of PCB per unit becomes large.

Further, dimethyl sulfoxide (DMSO)
When cleaning with a cleaning liquid, by heating (for example, around 80 ° C.) with a heating means or the like, the PCB and the insulation priority are efficiently separated, and due to strong permeability, gaps and cracks,
Dimethyl sulfoxide (DMSO) can enter the gaps between the paint and rust, and the PCB can be selectively dissolved and recovered.

Further, since a volatile solvent such as hexane has a low boiling point (about 69 ° C.), it has a problem in handling property, but dimethyl sulfoxide (DMSO) has a high boiling point (189 ° C.), so that the solvent volatilization amount is high. Less and more easily handled.

By adding a large amount of water to dimethyl sulfoxide (DMSO) containing PCB, dimethyl sulfoxide (DMSO) can be obtained as shown in the following "Chemical formula 2".
Is hydrolyzed, PCB is dissolved in water, and the water in which the PCB is dissolved is decomposed in a hydrothermal oxidative decomposition treatment device described later or another treatment device, which facilitates the treatment of the cleaning liquid. This is because water has a greater polarity than dimethylsulfoxide (DMSO), so the PCB migrates into the water. Since the solubility of PCB in water is 400 ppb, it is necessary to hydrolyze it with a large amount of water.

[0051]

[Chemical 2]

Therefore, according to the present embodiment, it is possible to easily wash and remove the PCB even if it is the object 1 to be treated in which the PCB has entered and adsorbed in the minute gaps on the surface.

Further, since sodium sulfate (Na ₂ SO ₄ ) which is a hydrolyzate is not corrosive, deterioration of the treatment equipment due to corrosion does not occur.

<PCB Processing Method> A case in which the cleaning apparatus 100 as described above is incorporated into, for example, a PCB processing system to detoxify the capacitor 20 will be described below with reference to FIG.

As shown in FIG. 5, first, PCB oil of the received condenser 20 is removed (S201), and the adhered P is removed.
CB level from about 50 g / m ² to 10-100 mg /
In order to reduce it to about m ^2, long-chain aliphatic hydrocarbons having low environmental toxicity and low flammability (for example, NS-10
Rough cleaning is performed using an organic solvent such as 0 or kerosene) as a cleaning agent (S202). This rough cleaning suppresses the deterioration of the cleaning performance by reducing the inflow amount of PCB into the finish cleaning process and keeping the PCB contamination level of the equipment used in the finish cleaning process low. Then, the roughly washed capacitor 20 is disassembled and separated into organic substances such as paper and wood, the element 21, and other inorganic substances such as the container 25 and the insulator 29 (S203). Element 21 of this capacitor 20
Generally has a structure in which an aluminum foil electrode, a plastic film, and a laminate of insulating paper are wound.

Next, the separated element 21 is heated and carbonized (S204). Carbonization by heating is performed in vacuum or Ar, N ₂
The temperature is 200 ~.
It is preferable to set the temperature to about 600 ° C. and the heating time to about 3 to 12 hours. By heating and carbonizing the element 21 in this manner, it is possible to remove the PCB or reduce the concentration thereof, and it is also possible to embrittle organic substances such as a plastics film and insulating paper, thereby decomposing and separating the element 21. Make it easier.

The element 21 thus heated and carbonized is
Separated into organic matter (embrittlement) and aluminum foil (S
205). In addition, in embrittlement of the said organic substance of the element 21, you may make it freeze or irradiate with ultraviolet rays instead of heating carbonization. Further, embrittlement by microorganisms is possible.

Subsequently, the organic substances separated from the element 21 and other organic substances such as paper and film generated at the time of disassembling are finely pulverized by a fine pulverizing mill to form a slurry (S2).
06). On the other hand, the aluminum foil separated from the element 21 and other metals generated during disassembly and inorganic substances such as insulators are
It is cleaned by the cleaning device 100 described above, and is discarded or reused (S207).

Then, the slurried organic matter and the cleaning waste liquid are hydrothermally decomposed together with the extracted insulating oil and the cleaning waste liquid at the time of cleaning to become NaCl, CO ₂ and H ₂ O and discharged (S208). As a result, the capacitor 20 including the PCB can be safely and reliably processed.

In such a PCB processing system, among the components of power equipment such as the capacitor 20, the PC
Since the organic waste such as paper and wood contaminated with B is separated from other components and taken out, and this organic waste is hydrothermally decomposed, it is safe and reliable including the PCB soaked in the organic matter. Can be processed.

At this time, since the organic waste such as paper and wood is slurried and the slurried organic waste is hydrothermally decomposed, the PCB should be treated safely and reliably and continuously. You can

In addition, among the constituent materials of electric power equipment such as the capacitor 20, inorganic waste such as metal and insulator contaminated by PCB is separated from other constituent materials and taken out, and after cleaning with a cleaning agent, the cleaning agent Since it is hydrothermally decomposed,
The cleaning agent contaminated by PCB can be safely and surely rendered harmless.

Further, since the organic waste such as paper and wood contaminated by the PCB and the cleaning agent contaminated by the PCB by cleaning the metal, the insulator and the like are hydrothermally decomposed, further safety and reliability are ensured. PCB processing can be performed.

Further, dimethyl sulfoxide (DMSO)
Tetrahydrofuran (THF) may be used alone or as a mixture instead of the cleaning liquid. Tetrahydrofuran (THF) is preferable because it has a high dissolving power especially for resin materials. In addition, tetrahydrofuran (TH
F) has a boiling point of around 65 ° C. and dimethyl sulfoxide (D
Since it is lower than MSO), it is necessary to heat at about 40 ° C. when heating.

Therefore, after the insulating oil mixed with PCB is drained from the condenser or transformer in which the insulating oil mixed with PCB is sealed, the cleaning agent containing only tetrahydrofuran or dimethyl sulfoxide is added to the boiling point of tetrahydrofuran. Heat (eg 40 ° C) to
By stirring, etc., paint, resin, PCB can be efficiently dissolved together with insulating oil, etc.
The cleaning agent can enter the gaps between the paint and rust, and all the organic compounds attached such as PCB can be dissolved and collected.

<Toxic Substance Treatment System> Further, the cleaning apparatus 100 can be used more effectively by incorporating it into a hazardous substance treatment system as shown in FIG.

As shown in FIG. 6, the harmful substance treatment system is a harmful substance treatment system for detoxifying an object to be treated on which harmful substances are attached, contained or stored. Etc.) 1001 is a first separating means 1004 for separating the harmful substance 1002 from a container 1003 for storing the harmful substance (eg PCB) 1002 and the constituent materials 1001a, b, ... Pretreatment means having one or both of the disassembling means 1005
1006 and constituent materials (core, capacitor element portion, etc.) 1001a constituting the object processed by the pretreatment means 1006,
Second separation means 1009 for separating organic matter 1007 such as paper, wood, resin, etc. and inorganic matter 1008 such as metal from b, ..., Metal container 1003 separated by the pretreatment means 1006, or the separation means 1009 The cleaning means 1011 for cleaning the inorganic substance 1008 such as the metal separated by the cleaning solution 1010, the cleaning waste liquid 1012 after cleaning, and the harmful substance 1001 separated by the pretreatment means. 1013 and are provided.

In such a hazardous substance treatment system, the cleaning device 100 is used as the cleaning means 1011.

According to such a harmful substance treatment system, the PCB concentration of the transformer 10, the capacitor 20, etc.
0.5 pp below the current PCB emission standard value (3 ppb)
It can be reduced to b or less, and the transformer 10 including the PCB, the capacitor 20 and the like can be processed safely and reliably. Therefore, the PCB-containing article can be completely processed, and the PCB can be completely extinguished.

Since organic compounds other than PCB can be treated, dioxins contained in PCB, organic substances such as paper, wood, cloth, etc. contaminated by PCB, and cleaning agents used for cleaning the case are also used. It can be decomposed similarly.

FIG. 7 shows a hydrothermal decomposition treatment system 1 for PCB.
It is a block diagram of 20.

As shown in FIG. 7, a cylindrical primary reactor 1
22 and oil 123a for combustion, drained PCB123
b, sodium hydroxide (NaOH) 123c and water 12
Pressurizing pumps 124a to 124d for pressurizing 3d respectively,
Preheater 12 for preheating a mixed solution of water and sodium hydroxide
5, and a secondary reactor 126 having a structure in which piping is wound, for example,
The cooler 127 and the pressure reducing valve 128 are provided. Also,
A steam separator 129 and an activated carbon tank 130 are arranged downstream of the pressure reducing valve 127, and exhaust gas (CO ₂ ) 131 is discharged from a chimney 132 to the outside, and waste water (H ₂ O, NaC) is discharged.
l) 133 is separately treated as waste water as required. The oxygen pipe 135 is directly connected to the primary reactor 125. As for the reactor, for example, a plurality of primary reactors may be arranged in parallel, or the secondary reactor 126 may be omitted as necessary.

In the above apparatus, the pressure pumps 124a ...
The pressure in the primary reactor 122 is 26
The pressure is increased to MPa. Further, the preheater 125 uses water and N
The mixed treatment solution of aOH is preheated to about 300 ° C. Also,
Oxygen is ejected into the primary reactor 122,
Heat up to 380 ℃ -400 ℃ subcritical range
It Sodium carbonate precipitated in this subcritical hot water
(Na₂CO₃) Crystal reacts with PCB, dechlorination reaction
Reaction and oxidative decomposition reaction, resulting in NaCl, CO ₂And
And H₂It is decomposed into O. Next, in the cooler 127
Cools the fluid from the secondary reactor 126 to about 100 ° C.
At the same time, the pressure is reduced to atmospheric pressure by the pressure reducing valve 128 in the subsequent stage.
It Then, by the steam separator 129, CO₂And water vapor
CO and treated water are separated, CO₂And steam is active
It passes through the charcoal tank 130 and is discharged into the environment. Also drain
Sodium chloride is mixed in 133, but separate
After salt treatment, re-use the water 28 used in the hydrothermal decomposition device.
Can be used.

Here, the primary reaction vessel 122 which is a reaction tower
And hydrothermal decomposition reaction of PCB in the secondary reactor 122.
And explain. First of all, when starting the reaction, oil, organic solvent, etc.
The oxidant supplied from the oxidant supply source into the tower (the present embodiment
Then oxygen is used) to produce carbon dioxide
To do. For example, the oil used as a combustion material (for example, toluene)
For example, when used, C ₆H_FiveCH₃+ 9O₂→
4H₂O + 7CO₂Due to the reaction of₂Is generated. This
The oxidation reaction of is an exothermic reaction, so the temperature inside the system
Rises and the pressure rises accordingly. In this embodiment
Indicates that the temperature and pressure inside the primary reaction container 122 are 38
When the temperature is maintained at 0 ° C and 26 MPa, the PCB content is the highest.
It has been found that the solution rate improves.

The CO ₂ produced as described above reacts with the sodium hydroxide supplied together with the PCB in the primary reaction vessel 122 to produce sodium carbonate (Na ₂ CO ₃ ). 2NaOH + CO ₂ → Na ₂ CO ₃ + H ₂ O (A) Next, Na ₂ CO produced by the reaction of the above (A)
₃ reacts with PCB, desalting and oxidatively decomposing PCB. C ₁₂ H ₆ Cl ₄ + 12.5O ₂ + 2Na ₂ CO ₃ → 4NaCl + 3H ₂ O + 14CO ₂ (B) In the case of the above-mentioned PCB having a chlorine number of 4, the same reaction is obtained for other chlorine numbers. Occurs, PCB is H ₂
It is decomposed into O, CO ₂ , and NaCl. The CO ₂ generated by the above reaction (B) is further converted into N ₂ by the above reaction (A).
Na ₂ CO that reacts with aOH and is required for the reaction of (B)
_Will generate ₃ . By the way, the above (B) PC
In the B decomposition reaction, sodium carbonate (Na ₂ C
O ₃ ) acts not only as a reaction agent but also as a catalyst for promoting the decomposition reaction of (B). Further, it has been found that the decomposition reaction of the above (B) is promoted in an alkaline atmosphere (for example, pH 10 or higher).

According to the hot water decomposing apparatus 120, it is possible to decompose to 0.5 ppb or less, which is less than the current PCB discharge standard value (3 ppb), and complete decomposition is possible. This allows PCB
It becomes possible to completely treat the contained article and completely eliminate the PCB.

As described above, the hydrothermal decomposition system 120
By using, it becomes possible to surely decompose the PCB in hot water. In addition, organic compounds other than PCB can also be decomposed, and dioxins contained in PCB, organic substances such as paper, wood, cloth, etc. contaminated by PCB, and cleaning agents used for cleaning the case can also be decomposed. It will be possible. The above hydrothermal decomposition method has already been disclosed by the applicant of the present application, and for details, refer to JP-A Nos. 11-639 and 11-253795. According to the PCB processing method described above, it is possible to safely and reliably process a transformer or the like including a PCB.

[Second Embodiment] A second embodiment of the cleaning method and apparatus according to the present invention will be described with reference to FIG. FIG. 8 is a schematic configuration diagram of the cleaning device. However, the same parts as those in the above-described first embodiment are denoted by the same reference numerals as those used in the description of the above-described embodiment, and the description thereof will be omitted.

As shown in FIG. 8, a heating tank 211 capable of sealing the inside is provided with a high-frequency heater 212 as a heating means. Above the heating tank 211, the heating tank 2
A suction pump 213 for suctioning the inside of the chamber 11 under reduced pressure is connected via an adsorption tank 214 filled with an adsorbent such as activated carbon and a three-way valve 215. A bracket 211 a that supports the cleaning casing 101 is attached inside the heating tank 211. In this embodiment, the suction pump 213,
The adsorbing tank 214, the three-way valve 215, etc. constitute an environment adjusting means.

Using such a cleaning device 200, P
When cleaning the object to be processed 1 in which CB remains on the surface and is adsorbed and remaining in the minute gaps, the object to be processed 1 is placed in the cleaning case 101, and the cleaning case 101 is heated by the heating tank 211. After putting it inside and placing it on the bracket 211a and sealing the heating tank 211, the suction pump 213 is operated to depressurize the inside of the heating tank 211 to create a vacuum environment (5KP
a) or less), the high-frequency heater 212 is operated to heat the object 1 by high-frequency (200 to 600 ° C.).

Then, the PCB adhering to the surface of the object to be processed 1 is vaporized and separated from the surface, and P is adsorbed in a fine gap such as rust formed on the surface of the object to be processed 1.
The CB is also vaporized, flows out from the gap, and is adsorbed and removed by the adsorption tank 214, so that the object to be treated 1 is dried and washed.

That is, by heating and vaporizing the PCB,
By causing a remarkably large molecular motion in the PCB, the PCB is easily separated from the minute gap such as rust formed on the surface of the object to be processed 1 and dried and washed.

Therefore, as in the case of the above-described first embodiment, the PCB concentration remaining on the object to be processed 1 can be significantly reduced as compared with the conventional one (about 1/400 or less).

Therefore, according to the present embodiment, as in the case of the above-described first embodiment, P is formed in the fine gap.
Even if the object 1 to be treated has CB invaded and adsorbed, P
The CB can be easily washed and removed sufficiently.

In the present embodiment, the high frequency heater 212 utilizing high frequency heating is used, but the present invention is not limited to this, and as another embodiment, for example,
It is also possible to use a radiant heater that utilizes radiant heat.

[Third Embodiment] A third embodiment of the cleaning method and apparatus according to the present invention will be described with reference to FIG. FIG. 9 is a schematic configuration diagram of the cleaning device. However, the same parts as those in the above-described first embodiment are denoted by the same reference numerals as those used in the description of the above-described embodiment, and the description thereof will be omitted.

As shown in FIG. 9, the cleaning device 301 according to the present embodiment has a dimethyl sulfoxide (DM)
(SO) A cleaning tank 303 having a spraying means 302 for spraying the cleaning liquid 2, a cleaning waste liquid tank 305 for recovering the cleaning waste liquid 304, and a transformer 306 to be processed.
And a supply pump 307 for supplying the cleaning liquid 304 to the inside of the container, and the PCB-containing transformer 30 installed inside.
If the PCB evaporates at the time of draining the liquid of 6, the mist or vapor is absorbed by the sprayed DMSO cleaning liquid 2. The sprayed cleaning liquid is stored in the lower part of the cleaning tank 300, and is appropriately guided to the cleaning waste liquid tank 305. In the present embodiment, the drained transformer 3 is used.
Although the collected cleaning waste liquid 304 is used for cleaning the inside of 06, the cleaning liquid 2 may be separately prepared for cleaning.

By making the inside of the cleaning tank 303 a cleaning liquid atmosphere having a saturation or higher, it is possible to prevent the evaporated PCB from being absorbed and scattered to the outside. In addition, the exhaust gas 31 provided outside
It is possible to prevent deterioration of the activated carbon filter 311 for treating 0 due to adsorption of PCB.

The cleaning waste liquid 308 containing PCB after the cleaning of the transformer 306 is introduced to the hydrothermal oxidation decomposition processing apparatus 120 shown in FIG. 7 and is decomposed therein.

[Other Embodiments] <Other Cleaning Devices> Other than the cleaning devices of the above-described embodiments, for example, the object 1 to be processed can be cleaned in a CO ₂ supercritical fluid. is there.

<Toxic Substances> In addition to the above PCBs, examples of the harmful substances that can be treated in the present invention include waste paint, waste fuel, hazardous chemicals, untreated explosives and the like. However, the present invention is not limited to these, and any harmful substance such as an environmental hormone caused by environmental pollution can be treated in the same manner.

[0092]

INDUSTRIAL APPLICABILITY As described above, in the cleaning method for removing harmful substances adhering to the minute gaps on the surface of the object to be processed, the object to be processed is immersed in a dimethyl sulfoxide (DMSO) cleaning solution. As a result, the cleaning liquid is allowed to enter the gap and the harmful substances attached to the gap are cleaned and removed. Therefore, organic halides such as PCB can be selectively removed, and the number of cleaning steps can be reduced. Can be achieved.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a first embodiment of a cleaning device according to the present invention.

FIG. 2 is a schematic configuration diagram of a transformer.

FIG. 3 is a schematic configuration diagram of a capacitor.

FIG. 4 is a schematic configuration diagram of a fluorescent lamp ballast.

FIG. 5 is an explanatory diagram of an embodiment of a PCB processing system using the cleaning apparatus according to the present invention.

FIG. 6 is an overall configuration diagram of an embodiment of a harmful substance treatment system using a cleaning device according to the present invention.

FIG. 7 is a schematic configuration diagram of a hydrothermal oxidative decomposition treatment apparatus.

FIG. 8 is a schematic configuration diagram of a second embodiment of a cleaning device according to the present invention.

FIG. 9 is a schematic configuration diagram of a third embodiment of a cleaning device according to the present invention.

FIG. 10 is a graph showing the relationship between the cleaning performance index of a dimethylsulfoxide (DMSO) cleaning liquid and other cleaning liquids, and the number of carbon atoms (pieces) of the cleaning agent.

FIG. 11 is an explanatory diagram of a conventional harmful substance processing system.

FIG. 12 is an explanatory diagram of the surface state of PCB contaminants.

[Explanation of symbols]

1 Object to be processed 2 cleaning liquid 3 inert gas 4 water 5 steam 6 acids 7 additives 8 Electrolyte stock solution 10 transformers 20 capacitors 30 fluorescent light ballast 100 cleaning equipment 111 cleaning tank 112 Cleaning liquid supply device 113 Ultrasonic oscillator 114 discharge valve 200 cleaning equipment 211 heating tank 212 high frequency heater 213 Suction pump 214 adsorption tank 215 three-way valve 301 cleaning device 302 spraying means 303 washing tank 304 Washing waste liquid tank 305 PCB containing transformer 306 Washing waste liquid tank 307 Washing waste liquid 308 Washing waste liquid 1001 object 1002 Hazardous substances (eg PCB) 1003 containers 1004 Separation means 1005 Dismantling method 1006 Pretreatment means 1007 organic matter 1008 inorganic 1009 Separation means 1010 cleaning solution 1011 Cleaning means 1012 Wash waste liquid 1013 Hazardous substance decomposition processing means 1014 slurry 1015 Slurrying means

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) B05D 1/02 B05D 1/02 Z 4F042 3/10 3/10 F 4H003 B08B 3/02 B08B 3/02 A 3/08 3/08 Z 3/10 3/10 A 3/12 3/12 A C11D 7/34 C11D 7/34 17/00 17/00 (72) Inventor Keigo Baba 5, Fukahori-cho, Nagasaki-shi, Nagasaki Prefecture 717 1 In Choryo Engineering Co., Ltd. (72) Inventor Yoshinori Fukunaga 5-chome, Fukahori-cho, Nagasaki City, Nagasaki Prefecture 717 1 F-term in Choryo Engineering Co., Ltd. (reference) 3B116 AA23 BB02 BB82 BB83 CA03 CC03 CD31 3B201 AA23 AB03 BB02 BB21 BB82 BB83 BB95 BB98 BB99 CA03 CC12 CD11 CD31 4D075 AA01 AA74 AB03 AB41 BB65Z BB69Z DB11 DC19 EA05 EC30 4F033 AA04 BA03 DA05 EA06 HA01 4F040 AA12 AB13 BA42 CC07 4F042 AA06 AB00 CC01 BA42 B21 4H003 BA12 DA12 DA14 EB21 ED32 FA03

Claims (15)

[Claims] 1. A cleaning method for removing harmful substances adhering to an object to be treated, wherein the object to be treated is immersed in a dimethyl sulfoxide (DMSO) cleaning solution to remove the harmful substances by washing. And the cleaning method. 2. The cleaning method according to claim 1, wherein the cleaned object is heated in an inert gas atmosphere under a reduced pressure environment to dry the object to be cleaned. . 3. A cleaning method for removing harmful substances adhering to the inside of an object to be treated, comprising supplying a dimethylsulfoxide (DMSO) cleaning solution into the object to be cleaned to wash the inside thereof. A cleaning method characterized by cleaning and removing. 4. The cleaning method according to claim 3, wherein the cleaning is performed in a saturated atmosphere of a dimethyl sulfoxide (DMSO) cleaning liquid. 5. The cleaning method according to claim 1 or 3, wherein the harmful substance is at least one of PCB, waste paint, waste fuel, and harmful chemicals. 6. The cleaning method according to claim 1, wherein the object to be processed is an inorganic member of a transformer or a capacitor containing PCB. 7. The cleaning method according to claim 1, wherein the member is a rusted container. 8. A cleaning device for removing harmful substances adhering to an object to be processed, comprising a cleaning tank in which the object to be processed is put and a dimethyl sulfoxide (DMSO) cleaning liquid is put inside. A characteristic cleaning device. 9. A cleaning device for removing harmful substances adhering to an object to be processed, wherein a heating tank in which the object to be processed can be sealed and the inside can be sealed, and the inside of the heating tank is inert under a vacuum environment. A cleaning apparatus comprising: an environment adjusting means for setting an environment under a gas atmosphere, and a heating means for heating the inside of the heating tank. 10. The cleaning device according to claim 8, wherein the tank is provided with ultrasonic wave oscillating means. 11. The heating tank according to claim 8, wherein the object to be processed can be put inside and the inside can be sealed, and an environment adjusting means for making the inside of the heating tank an inert gas atmosphere under a vacuum environment, A cleaning device, comprising: a heating unit configured to heat the inside of the heating tank. 12. A cleaning device for removing harmful substances adhering to fine gaps on the surface of an object to be treated, wherein dimethyl sulfoxide (DMS) is provided inside the object to be treated.
O) cleaning liquid supply means for supplying a cleaning liquid, and dimethylsulfoxide (DM) under the atmosphere of the object to be treated.
SO) a dimethylsulfoxide (DMSO) cleaning liquid spraying means under a vapor saturated atmosphere, and a cleaning device. 13. The cleaning device according to claim 8 or 12, wherein the harmful substance is at least one of PCB, waste paint, waste fuel, and harmful chemicals. 14. The cleaning device according to claim 8 or 12, wherein the object to be processed is an inorganic member of a transformer or a capacitor containing PCB. 15. The cleaning device according to claim 8 or 12, wherein the member is a rusted container.