JP2002059091A - Method and apparatus for cleaning member to which polychlorobiphenyls are adhered - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for cleaning a member to which PCBs are adhered which can treat waste liquid after cleaning treatment simply at a low cost and an apparatus for the method. SOLUTION: Water 1 is introduced into a cleaning tank 11 by operating a water supply pump 13, a surfactant 2 is added from a surfactant adding device 14 into the tank 11, the member 100 to which the PCBs are adhered is immersed in surfactant-containing water 3, an ultrasonic wave generator 12 is operated, the member 100 is irradiated with ultrasonic waves, the water 3 is extracted from the tank 11, water 1 is introduced again into the tank 11, the member 100 is immersed in the water 1, the generator 12 is operated, the member 100 is irradiated again with ultrasonic waves, rinsing cleaning is performed, and the member 100 is removed from the tank 11 and dried.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for cleaning polychlorinated biphenyls remaining on members such as electric equipment such as transformers and capacitors.

[0002]

2. Description of the Related Art In electrical equipment such as transformers and capacitors, polychlorinated biphenyls (PCBs) having excellent insulating properties have conventionally been used as insulating oils. Since these PCBs have an adverse effect on the human body and the environment, their use and production as well as insulators for the above-mentioned electrical equipment are currently prohibited. For this reason, in the above-mentioned electric equipment and the like using PCBs as insulating oil, the insulating oil is extracted from the inside and subjected to detoxification processing, and at the same time, members such as the case where the PCBs are adhered and remaining are cleaned.

[0003] In the cleaning treatment of a member having PCBs remaining thereon, conventionally, the member is immersed in an organic solvent such as n-hexane and subjected to ultrasonic cleaning to obtain a concentration of PCBs remaining on the surface of the member. Is repeated until the value becomes equal to or less than a specified value (10 μg / m ² ) (usually, about 5 to 6 times).

[0004]

However, when the members are washed as described above, a large amount of waste liquid of the organic solvent containing PCBs is generated, and it becomes difficult to treat the waste liquid, resulting in high processing cost. Was gone.

Accordingly, an object of the present invention is to provide a method and an apparatus for cleaning a member to which polychlorinated biphenyls can be attached, which can easily carry out waste liquid treatment after cleaning treatment at low cost.

[0006]

Means for Solving the Problems A method for cleaning a member to which polychlorinated biphenyls are adhered according to the first invention for solving the above-mentioned problem is a method for cleaning a member to which polychlorinated biphenyls are adhered. A surfactant-containing water washing step of washing the member with water containing a surfactant.

In a second aspect of the present invention, in the method for cleaning a member to which polychlorinated biphenyls are attached, in the first aspect, the step of washing the surfactant-containing water comprises placing the member in the water containing the surfactant. It is a step of immersing the member and irradiating the member with ultrasonic waves to wash the member.

[0008] In a third aspect of the present invention, in the method for cleaning a member to which polychlorinated biphenyls are attached, in the first or second aspect, the surfactant may be any one of anionic, cationic and nonionic types. It is one of the features.

A fourth aspect of the present invention is directed to the method for cleaning a member to which polychlorinated biphenyls are attached according to any one of the first to third aspects, wherein the content of the surfactant in the water is 0.5 to 50 vol. %.

In a fifth aspect of the present invention, there is provided the method for cleaning a member to which polychlorinated biphenyls are attached according to any one of the first to fourth aspects, wherein the member is washed with water after the step of washing with a surfactant-containing water. And performing a rinsing step of washing.

In a sixth aspect of the present invention, in the cleaning method of the fifth aspect, the rinsing step comprises immersing the member in water and irradiating the member with ultrasonic waves. This is a step of cleaning the member.

In a seventh aspect of the present invention, the method for cleaning a member to which polychlorinated biphenyls are attached is a method according to the fifth or sixth aspect, wherein the surfactant-containing water cleaning step and the rinsing step are alternately performed in plural. It is carried out twice.

An eighth aspect of the present invention provides a method for cleaning a member to which polychlorinated biphenyls are attached, according to any one of the first to seventh aspects, wherein an oil cleaning step of cleaning the member with a cleaning oil is performed. And

In a ninth aspect of the present invention, in the method for cleaning a member to which polychlorinated biphenyls are attached, in the oil cleaning step, the member is immersed in the oil and irradiated with ultrasonic waves. And cleaning the member.

According to a tenth aspect of the present invention, in the method for cleaning a member to which polychlorinated biphenyls are attached according to the eighth aspect, in the oil cleaning step, the member is immersed in the oil and left to stand. It is a step of immersion cleaning.

The method for cleaning a member to which polychlorinated biphenyls are attached according to a tenth aspect of the present invention is the method according to any one of the eighth to tenth aspects, wherein the oil is kerosene or low-concentration polychlorinated biphenyls. It is characterized by contaminated oil.

According to a twelfth aspect of the present invention, there is provided a method for cleaning a member to which polychlorinated biphenyls are attached according to any one of the first to tenth aspects, wherein the member is immersed in an aqueous alkali solution to apply a voltage to the member. Is applied to perform an electrolytic cleaning step of cleaning the member.

A thirteenth aspect of the present invention provides the method of cleaning a member to which polychlorinated biphenyls are attached according to the twelfth aspect, wherein the alkaline aqueous solution is an aqueous solution of at least one of sodium hydroxide and sodium carbonate. It is characterized by.

A fourteenth invention provides a method for cleaning a member to which polychlorinated biphenyls are attached according to the twelfth or thirteenth invention, wherein the alkali aqueous solution has an alkali concentration of 5 to 30 wt%. Features.

According to a fifteenth aspect of the present invention, in the method for cleaning a member to which polychlorinated biphenyls are attached, in any one of the twelfth to fourteenth aspects, the applied voltage in the electrolytic cleaning step is 4 to 8 V. It is characterized by the following.

According to a sixteenth aspect of the present invention, there is provided an apparatus for cleaning a member to which polychlorinated biphenyls are adhered, the apparatus comprising: And a washing tank for storing
A surfactant-containing water storage means for storing water containing a surfactant in the washing tank;

A seventeenth aspect of the present invention is directed to the cleaning apparatus for a polychlorinated biphenyl-adhered member according to the sixteenth aspect, wherein the surfactant-containing water storage means supplies water into the cleaning tank. And a surfactant adding means for adding the surfactant into the cleaning tank.

An eighteenth aspect of the present invention is directed to the cleaning apparatus for cleaning a member to which polychlorinated biphenyls are attached according to the sixteenth or seventeenth aspect. Is provided.

A nineteenth aspect of the present invention is the apparatus for cleaning a member attached with polychlorinated biphenyls according to any one of the sixteenth to eighteenth aspects, wherein the oil supply means supplies cleaning oil into the cleaning tank. Is provided.

According to a twentieth aspect of the present invention, there is provided the apparatus for cleaning a member attached with polychlorinated biphenyls according to any one of the sixteenth to nineteenth aspects, wherein the alkaline aqueous solution is stored in the cleaning tank. Means, and voltage applying means for applying a voltage to the member.

[0026] In the apparatus for cleaning a member to which polychlorinated biphenyls are attached according to a twentieth aspect of the present invention, in the twentieth aspect, the alkaline aqueous solution storage means may include a water supply means for supplying water into the cleaning tank; And an alkali addition means for adding an alkali or an aqueous alkali solution to the washing tank.

[0027]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of a method and an apparatus for cleaning a member to which polychlorinated biphenyls (PCBs) are adhered according to the present invention will be described below, but the present invention is not limited to these embodiments. is not.

[First Embodiment] P according to the present invention
A first embodiment of a method and an apparatus for cleaning CB-attached members will be described with reference to FIGS. FIG. 1 is a schematic configuration diagram of a cleaning device, and FIG. 2 is an explanatory diagram of a procedure of a cleaning method.

As shown in FIG. 1, an ultrasonic wave generating means for irradiating an ultrasonic wave toward the inside of the cleaning 11 is provided in a cleaning tank 11 in which the member 100 on which the PCBs are adhered remains. A generator 12 is attached. Above the cleaning tank 11, a water supply pump 13 is a water supply means for supplying water 1 into the cleaning tank 11, and a surfactant is a surfactant adding means for adding a surfactant 2 into the cleaning tank 11. The agent adding device 14 is in communication. A discharge valve 15 is connected to a lower portion of the cleaning tank 11. In FIG. 1, reference numeral 14a denotes a valve, and 101 denotes a fishing support of the member 100. Further, in the present embodiment, the water supply pump 13, the surfactant addition device 14, and the like constitute a surfactant-containing water storage means.

Next, a method of cleaning a PCB-attached member using the apparatus for cleaning a PCB-attached member will be described.
The member 100 is supported by the fishing support 101 and put into the washing tank 11, the water supply pump 13 is operated to put water 1 into the washing tank 11, and the valve 14 a of the surfactant adding device 14 is operated. A surfactant 2 is added to the cleaning tank 11 to obtain a surfactant-containing water 3 having a specified concentration.
After the immersion of the member 100, the ultrasonic wave generator 12 is operated to irradiate the member 100 with ultrasonic waves.
0 is ultrasonically cleaned in surfactant-containing water 3 (surfactant-containing water cleaning step A).

A prescribed time (several minutes to
1 hour) After the ultrasonic cleaning, the discharge valve 15 is operated to transfer the water 3 from the cleaning tank 11 to a waste liquid tank (not shown), and then the water supply pump 13 is operated to put the water 1 into the cleaning tank 11 again. Then, the member 100 is immersed in the water 1,
By operating the ultrasonic generator 12 and irradiating the member 100 with ultrasonic waves again, ultrasonic cleaning with water 1 is performed (rinse cleaning step B).

After the ultrasonic cleaning in the water 1 for a specified time (about several minutes), the water 1 is operated by operating the drain valve 15.
From No. 1 is transferred into a waste liquid tank (not shown). Hereinafter, member 10
The concentration of PCBs remaining on the surface of No. 0 is a specified value (10
When the above-described surfactant-containing water washing step A and the rinsing washing step B are alternately performed a plurality of times (usually about twice) until the amount becomes not more than μg / m ² ), the member 100 is taken out from the washing tank 11 and dried. After the drying (drying step X), it is sent to a subsequent step such as scrapping and recycling.

On the other hand, the waste liquids of the waters 1 and 3 generated by the washing can be obtained by applying a hydrothermal decomposition method as disclosed in, for example, Japanese Patent Application Laid-Open No. 11-639, etc. It is easily decomposed and rendered harmless.

Therefore, according to such a cleaning method and a cleaning apparatus, it is not necessary to use an organic solvent, and the waste liquid after the cleaning can be easily processed at low cost.

The surfactants used in the present invention include anionic, cationic and nonionic surfactants, but the nonionic or cationic surfactants are suitable for the hydrothermal decomposition treatment. It is preferable to apply the nonionic type system, and it is particularly preferable to apply the nonionic type, since the detergent can be easily rinsed and removed even with water at normal temperature.

The content (concentration) of the surfactant 2 in the surfactant-containing water 3 is preferably 0.5 to 50 vol.%, And particularly preferably 3 to 10 vol.%. preferable. If the concentration is less than 0.5 vol.%, The cleaning effect is reduced, and if it exceeds 50 vol.%, The concentration of PCB contained in the surfactant remaining on the surface of the member after cleaning becomes high. This is because the amount of water used in the next rinsing step increases, and when the amount is 3 to 10 vol.%, The balance between economy and cleaning performance is best.

The present embodiment is extremely effective when applied to the case of cleaning the member 100 on which the PCB-contaminated liquid of a low concentration (less than 1%) adheres and remains. Specifically, for example, initially, PCBs were used as insulating oil,
For example, there is a case where a transformer case or the like is replaced with another harmless insulating oil on the way.

[Second Embodiment] P according to the present invention
A second embodiment of a method and an apparatus for cleaning CB-attached members will be described with reference to FIGS. FIG. 3 is a schematic configuration diagram of a cleaning device, and FIG. 4 is a diagram illustrating a procedure of a cleaning method. However, the same portions as those in the first embodiment described above are denoted by the same reference numerals as those used in the description of the first embodiment, and the description thereof is omitted.

As shown in FIG. 3, an oil supply pump 26 serving as an oil supply means for supplying the washing oil 4 such as kerosene into the washing tank 11 is connected above the washing tank 11. Other parts are the same as those in the first embodiment.

Next, a method of cleaning a PCB-attached member using the apparatus for cleaning a PCB-attached member will be described.
The member 100 is supported by the fishing jig 101 and put into the cleaning tank 11, and the oil supply pump 26 is operated to put the cleaning oil 4 in the cleaning tank 11.
After the member 100 is immersed in the cleaning oil 4, the member 100 is ultrasonically cleaned in the cleaning oil 4 by operating the ultrasonic generator 12 and irradiating the member 100 with ultrasonic waves. (Oil cleaning step C1).

After ultrasonic cleaning in the cleaning oil 4 for a specified time (several minutes to one hour), the drain valve 15 is operated to transfer the oil 4 from the cleaning tank 11 to a waste liquid tank (not shown). Is operated to put water 1 into the washing tank 11, and the surfactant 14 is added into the washing tank 11 by operating the valve 14 a of the surfactant adding device 14, and the surfactant-containing water having a specified concentration is added. After immersing the member 100 as 3,
Activating the ultrasonic generator 12 to generate ultrasonic waves from the member 100
The member 100 is subjected to ultrasonic cleaning in the surfactant-containing water 3 (surfactant-containing water cleaning step A).

In the surfactant-containing water 3 for a specified time (several minutes to
1 hour) After the ultrasonic cleaning, the discharge valve 15 is operated to transfer the water 3 from the cleaning tank 11 to a waste liquid tank (not shown), and then the water supply pump 13 is operated to put the water 1 into the cleaning tank 11 again. Then, the member 100 is immersed in the water 1,
Activating the ultrasonic generator 12 to generate ultrasonic waves from the member 100
Is again irradiated to perform ultrasonic cleaning with water 1 (rinse cleaning step B).

After ultrasonic cleaning in the water 1 for a specified time (about several minutes), the drain valve 15 is operated to remove the water 1 from the cleaning tank 1.
From No. 1 is transferred into a waste liquid tank (not shown). Hereinafter, member 10
The concentration of PCBs remaining on the surface of No. 0 is a specified value (10
When the above-described surfactant-containing water washing step A and the rinsing washing step B are alternately performed a plurality of times (usually about twice) until the amount becomes equal to or less than μg / m ² ), the member 100 is taken out from the washing tank 11 and dried. After the drying (drying step X), it is sent to a subsequent step such as scrapping and recycling.

On the other hand, the waste liquid of the water 1, 3 and the oil 4 generated by the washing is disclosed in, for example, Japanese Patent Application Laid-Open No. 11-639 as in the case of the first embodiment. By applying a hydrothermal decomposition method such as
The contained PCBs are easily decomposed and rendered harmless.

That is, in the present embodiment, prior to the cleaning according to the above-described first embodiment, an oil cleaning step C1 of irradiating ultrasonic waves using a cleaning oil 4 having high affinity for PCBs is prepared. This was done as washing.

Therefore, according to the present embodiment, it is possible to obtain the same effect as in the case of the first embodiment described above, as well as in the case of the first embodiment. Rather, the PCBs remaining on the member 100 can be more reliably washed and removed.

In this embodiment, the medium concentration (1 to 10
%) Or a high concentration (10 to 100%) of the PCBs contaminated liquid is extremely effective when applied to a case where the member 100 is left behind. Specifically, for example, a case of a transformer using a mixture of PCBs and other mineral oils as an insulating oil, a case of a transformer using PCBs as an insulating oil, and the like are exemplified. .

Further, instead of kerosene or the like as the cleaning oil 4, for example, low-concentration (less than 1%) PCB-contaminated liquid (for example,
If the PCBs used as the insulating oil in the transformer are replaced with other insulating oils), not only is it unnecessary to prepare a new cleaning oil 4, but also
Since the amount of liquid to be detoxified can be reduced, the processing efficiency can be improved and the processing cost can be further reduced.

[Third Embodiment] The P according to the present invention
A third embodiment of a method and an apparatus for cleaning CB-attached members will be described with reference to FIG. FIG. 5 is an explanatory diagram of the procedure of the cleaning method. However, the same parts as those in the first and second embodiments described above will be described by using the same reference numerals as those used in the description of the first and second embodiments. Is omitted.

The cleaning apparatus used in this embodiment is the same as that shown in FIG. 3 used in the second embodiment.

Next, a method for cleaning a PCB-attached member according to this embodiment will be described. The member 100 is connected to the fishing support 10
1 and put into the washing tank 11, and the oil supply pump 26 is operated to put the washing oil 4 into the washing tank 11, so that the member 100 is immersed in the washing oil 4. Thereby, the member 100 is immersed in the cleaning oil 4 for cleaning (oil cleaning step C2).

After immersion in the cleaning oil 4 for a prescribed period (one to several days), the drain valve 15 is operated to transfer the oil 4 from the cleaning tank 11 to a waste liquid tank (not shown). Is operated to put water 1 into the washing tank 11, and the surfactant 14 is added into the washing tank 11 by operating the valve 14 a of the surfactant adding device 14, and the surfactant-containing water having a specified concentration is added. After immersing the member 100 as 3,
The member 100 is ultrasonically cleaned in the surfactant-containing water 3 by irradiating the member 100 with ultrasonic waves by operating the ultrasonic generator 12 (surfactant-containing water cleaning step A).

A prescribed time (a few minutes to
1 hour) After the ultrasonic cleaning, the discharge valve 15 is operated to transfer the water 3 from the cleaning tank 11 to a waste liquid tank (not shown), and then the water supply pump 13 is operated to put the water 1 into the cleaning tank 11 again. Then, the member 100 is immersed in the water 1,
By operating the ultrasonic generator 12 and irradiating the member 100 with ultrasonic waves again, ultrasonic cleaning with water 1 is performed (rinse cleaning step B).

After the ultrasonic cleaning in the water 1 for a predetermined time (about several minutes), the water 1 is operated by operating the drain valve 15.
From No. 1 is transferred into a waste liquid tank (not shown). Hereinafter, member 10
The concentration of PCBs remaining on the surface of No. 0 is a specified value (10
When the above-described surfactant-containing water washing step A and the rinsing washing step B are alternately performed a plurality of times (usually about twice) until the amount becomes equal to or less than μg / m ² ), the member 100 is taken out from the washing tank 11 and dried. After the drying (drying step X), it is sent to a subsequent step such as scrapping and recycling.

On the other hand, the waste liquid of the water 1, 3 and the oil 4 generated by the washing is, for example, disclosed in Japanese Unexamined Patent Publication No. 11-639 as in the first and second embodiments. By applying the disclosed hydrothermal decomposition method, the contained PCBs components are easily decomposed and rendered harmless.

That is, the present embodiment is different from the second embodiment in that the ultrasonic cleaning with the cleaning oil 4 (the oil cleaning step C1) is performed instead of the ultrasonic cleaning (the oil cleaning step C1). ).

For this reason, in this embodiment, although it takes more time for the processing than in the case of the second embodiment described above, for example, the immersion cleaning is performed from the evening before the holiday to the end of the holiday. If the processing is performed over the morning, the processing time can be substantially the same as that of the second embodiment.

Therefore, according to the present embodiment, it is possible to obtain the same effect as that of the second embodiment described above, and the cleaning process with the cleaning oil 4 is performed by soaking. As a result, the running cost for the processing can be reduced as compared with the case of the above-described second embodiment.

In this embodiment, as in the case of the above-described second embodiment, the PCB (contaminated liquid) of medium concentration (1 to 10%) or high concentration (10 to 100%) adheres. This is extremely effective when applied to the case where the remaining member 100 is cleaned.

Further, instead of kerosene or the like as the cleaning oil 4, for example, low-concentration (less than 1%) PCB-contaminated liquid (for example,
If the PCBs used as the insulating oil in the transformer are replaced with other insulating oils), not only is it unnecessary to prepare a new cleaning oil 4, but also
Since the amount of liquid to be detoxified can be reduced, the processing efficiency can be improved and the processing cost can be further reduced.

[Fourth Embodiment] The P according to the present invention
A fourth embodiment of the method and the apparatus for cleaning the CB attachment member will be described with reference to FIGS. FIG. 6 is a schematic configuration diagram of a cleaning device, and FIG. 7 is a diagram illustrating a procedure of a cleaning method. However, for the same parts as in the first to third embodiments described above, the same reference numerals as those used in the description of the first to third embodiments described above are used to explain the same. Is omitted.

As shown in FIG. 6, an electrode 47a is provided inside the cleaning tank 11. This electrode 47a
It is connected to a negative electrode side of a DC power supply 47 provided outside the cleaning tank 11. The positive electrode side of the DC power supply 47 is connected to a connector 47b which is provided inside the cleaning tank 11 and is detachable from the member 100. On the other hand, above the cleaning tank 11, an alkaline aqueous solution 5 in which an alkali such as sodium hydroxide or sodium carbonate is dissolved in water is applied to the cleaning tank 1.
An alkali addition device 48, which is an alkali addition means to be added into 1, is connected. In the present embodiment, the refueling pump 26 is omitted. In FIG. 6, 4
8a is a valve. In this embodiment, the water supply pump 13, the alkali addition device 48 and the like constitute an alkaline aqueous solution storage means, and the DC power supply 47 and the electrode 4
The voltage applying means is constituted by 7a, the coupling tool 47b, and the like.

A method for cleaning a PCB-attached member using such a device for cleaning a PCB-attached member will be described below.
After the member 100 is supported by the fishing support 101 and put into the cleaning tank 11, the connecting tool 47 b is connected to the member 100, and then the water supply pump 13 is operated to put water 1 into the cleaning tank 11.
When the surfactant 2 is added to the cleaning tank 11 by operating the valve 14a of the surfactant addition device 14 to immerse the member 100 in the water 3 as the surfactant-containing water 3 having a specified concentration, Activating the ultrasonic wave generator 12 to activate the member 1
The member 100 is subjected to ultrasonic cleaning in the surfactant-containing water 3 by irradiating ultrasonic waves at 00 (surfactant-containing water cleaning step A).

In surfactant-containing water 3 for a specified time (several minutes to
1 hour) After the ultrasonic cleaning, the discharge valve 15 is operated to transfer the water 3 from the cleaning tank 11 to a waste liquid tank (not shown), and then the water supply pump 13 is operated to put the water 1 into the cleaning tank 11 again. At the same time, the valve 48 of the alkali addition device 48
a, the alkaline aqueous solution 5
Is added to make the aqueous solution 6 of the specified concentration, the member 100 is immersed in the aqueous solution 6.
Is operated to apply a voltage between the electrode 47a and the member 100 to perform electrolytic cleaning with the alkaline aqueous solution 6 (electrolytic cleaning step D).

A prescribed time (several minutes to 1
After the electrolytic cleaning, the drainage valve 15 is operated to transfer the water 1 from the cleaning tank 11 into a waste liquid tank (not shown), and then the water supply pump 13 and the surfactant addition device 14 are operated to remove the member 100. When immersed again in the surfactant-containing water 3, the ultrasonic generator 12 is operated to operate the member 1.
The member 100 is ultrasonically cleaned again in the surfactant-containing water 3 by irradiating the ultrasonic wave at 00 (surfactant-containing water cleaning step A).

In the surfactant-containing water 3 for a specified time (several minutes to
1 hour) After the ultrasonic cleaning, the discharge valve 15 is operated to transfer the water 3 from the cleaning tank 11 to a waste liquid tank (not shown), and then the water supply pump 13 is operated to put the water 1 into the cleaning tank 11 again. Then, the member 100 is immersed in the water 1,
Activating the ultrasonic generator 12 to generate ultrasonic waves from the member 100
Is again irradiated to perform ultrasonic cleaning with water 1 (rinse cleaning step B).

After ultrasonic cleaning in the water 1 for a specified time (about several minutes), the water 1 is operated by operating the drain valve 15.
From No. 1 is transferred into a waste liquid tank (not shown). Subsequently, after the member 100 is taken out from the cleaning tank 11 and dried (drying step X), it is sent to a post-process such as scrapping and recycling.

On the other hand, the water 1,3,6
The waste liquid is contained, for example, by applying a hydrothermal decomposition method as disclosed in Japanese Patent Application Laid-Open No. 11-639 or the like in the same manner as in the first to third embodiments described above. The PCB components are easily decomposed and rendered harmless.

In other words, this embodiment is different from the first rinse cleaning step B of the first embodiment described above in that
The electrolytic cleaning step D using the alkaline aqueous solution 6 is performed.

Therefore, according to the present embodiment, the same effect as that of the first embodiment can be obtained, and the electrolytic cleaning with the alkaline aqueous solution 6 is performed. Therefore, even if rust or the like is generated due to aging, PCBs can be reliably washed,
As compared with the case of the first embodiment described above, the member 10
PCBs adhering and remaining at 0 can be more reliably washed and removed.

The alkaline aqueous solution 6 used in the present invention may be any aqueous solution of various alkalis such as sodium hydroxide, sodium carbonate and sodium silicate.
There is no particular limitation. However, an alkaline aqueous solution 6 composed of at least one of sodium hydroxide and sodium carbonate is very advantageous because it is extremely advantageous when the waste liquid after electrolytic cleaning is treated by the hydrothermal decomposition method. This is because sodium hydroxide and sodium carbonate are added to the waste liquid when performing the hydrothermal decomposition, so that there is no fear of adversely affecting the hydrothermal decomposition. Further, it is preferable that the alkaline aqueous solution 6 does not contain a silicate such as sodium metasilicate. This is because, if silicate is contained in the waste liquid after the electrolytic cleaning, the silicate must be removed in performing the hydrothermal decomposition, and the post-treatment is troublesome.

The alkali concentration in the aqueous alkali solution 6 used in the present invention is preferably 5 to 30% by weight, and particularly preferably 5 to 10% by weight.
If it is less than 5 wt%, it cannot be sufficiently degreased, and if it exceeds 30 wt%, it must be further diluted when treating wastewater containing PCB.
%, It can be directly processed by hydrothermal decomposition.

The voltage applied during the electrolytic cleaning performed in the present invention is preferably 4 to 8 V, and more preferably 5 to 8 V.
It is very preferable that the voltage is 7V. If the voltage is less than 4 V, cleaning cannot be performed sufficiently due to insufficient electric field capability. If the voltage exceeds 8 V, excessive electrolysis is caused, a large amount of hydrogen gas is generated, and the member to be cleaned is dissolved.
The life of the cleaning solution is shortened.
This is because the best balance between the cleaning performance and the liquid life can be obtained.

Further, in this embodiment, the alkali aqueous solution 6 having an alkali dissolved in water is added to the water 1 in the cleaning tank 11 to obtain the alkaline aqueous solution 6 having a specified concentration. It is also possible to obtain an aqueous alkaline solution 6 having a specified concentration by adding a solid alkali to the water 1 in the washing tank 11. However, from the viewpoint of workability and safety, it is preferable to perform the operation as in the present embodiment.

In the present embodiment, a new alkaline aqueous solution 6 is used for electrolytic cleaning.
It is also possible to apply wastewater (an aqueous alkali solution composed of at least one of sodium hydroxide and sodium carbonate) for the hydrothermal decomposition in the post-process of decomposing PCBs in the waste liquid for electrolytic cleaning.

In this embodiment, as in the second and third embodiments, the medium density (1 to 10) is used.
%) Or a high concentration (10 to 100%) of the PCBs contaminated liquid is extremely effective when applied to a case where the member 100 is left behind.

In each of the above-described embodiments, the surfactant-containing water washing step A and the rinsing step B are performed a plurality of times (2 times).
Times), the oil cleaning steps C1 and C2 and the electrolytic cleaning step D
Depending on conditions such as the concentration of PCBs remaining on the member 100, the surfactant-containing water cleaning step A and the rinsing step B may be performed only once, or the oil cleaning step C1,
C2 and the electrolytic cleaning step D may be performed plural times.

Further, the present invention is not limited to the case described in each of the above-described embodiments, and the surfactant-containing water cleaning step A may be performed in accordance with conditions such as the concentration of PCBs remaining on the member 100. The above-described steps B to D can be arbitrarily combined at the center.

[0079]

EXAMPLES In order to confirm the effects of the present invention, the following confirmation experiments were performed.

Test Example 1 A low-concentration water (content: 3%) containing a surfactant (aid 40, manufactured by Nippon Surface Chemical Co., Ltd.) mainly containing nonionic components was added. PC
After immersing the member to which Class B (100 ppm) adheres and performing ultrasonic cleaning at room temperature for 5 minutes (surfactant-containing water cleaning step), the member is immersed in water and subjected to ultrasonic cleaning at room temperature for 5 minutes. (Rinse washing step). Subsequently, after the member is dried (drying step), the surface of the member is adjusted to a specified area (0.06
m ² ) or more, and the residual amount of PCBs per 1 m ² was determined.

Test Example 2 A low concentration of water (content: 3%) containing a surfactant (aid 40, trade name, manufactured by Nippon Surface Chemical Co., Ltd.) mainly containing nonionic components was added. PC
After immersing the member to which Class B (100 ppm) adheres and performing ultrasonic cleaning at room temperature for 10 minutes (surfactant-containing water cleaning step), the member is immersed in water and subjected to ultrasonic cleaning at room temperature for 5 minutes. (Rinse washing step). Subsequently, after the member is dried (drying step), the surface of the member is adjusted to a specified area (0.0%).
The residual amount of PCBs per 1 m ² was determined by wiping over 6 m ² ).

[Test Example 3] A low concentration of water (content: 3%) containing a surfactant (aid 40, manufactured by Nippon Surface Chemical Co., Ltd.) mainly containing nonionic components was added. PC
After immersing the member to which Class B (100 ppm) adheres and performing ultrasonic cleaning at room temperature for 15 minutes (surfactant-containing water cleaning step), the member is immersed in water and subjected to ultrasonic cleaning at room temperature for 5 minutes. (Rinse washing step). Subsequently, after the member is dried (drying step), the surface of the member is adjusted to a specified area (0.0%).
The residual amount of PCBs per 1 m ² was determined by wiping over 6 m ² ).

[Test Results] The test results of Test Examples 1 to 3 are shown in Table 1 below. As is clear from Table 1, it was confirmed that all of Test Examples 1 to 3 satisfied the specified value (10 μg / m ² or less).

[0084]

[Table 1]

[0085]

According to the first aspect of the present invention, there is provided a method for cleaning a member to which polychlorinated biphenyls are adhered, wherein the member to which polychlorinated biphenyls are adhered is washed with water containing a surfactant. Since the surfactant-containing water washing step is performed, the polychlorinated biphenyls can be washed away without using an organic solvent. Therefore, the waste liquid treatment after the cleaning treatment can be easily performed at low cost.

The method for cleaning a member to which polychlorinated biphenyls are attached according to a second invention is characterized in that, in the first invention, the step of washing the surfactant-containing water comprises placing the member in the water containing the surfactant. Since this is a step of immersing the member and irradiating the member with ultrasonic waves to wash the member, the polychlorinated biphenyls can be reliably removed by washing.

The method for cleaning a member to which polychlorinated biphenyls are attached according to a third aspect of the present invention is the method according to the first or second aspect, wherein the surfactant is an anionic, cationic or nonionic type surfactant. Since it is any one of them, washing and removal of polychlorinated biphenyls can be surely performed.

The method for cleaning a member to which polychlorinated biphenyls are attached according to a fourth aspect of the present invention is the method according to any one of the first to third aspects, wherein the content of the surfactant in the water is 0.5 to 50 vol. %, The polychlorinated biphenyls can be efficiently washed and removed.

The method for cleaning a polychlorinated biphenyl-adhered member according to a fifth aspect of the present invention is the method according to any one of the first to fourth aspects, wherein the member is washed with water after the surfactant-containing water washing step. Since the rinsing step is performed, the surfactant attached to the surface of the member can be removed without remaining.

The cleaning method of a member to which polychlorinated biphenyls are attached according to a sixth aspect of the present invention is the method of the fifth aspect, wherein the rinsing step comprises immersing the member in water and irradiating the member with ultrasonic waves. Since this is a step of cleaning the member, the surfactant attached to the surface of the member can be reliably removed.

The method for cleaning a member to which polychlorinated biphenyls are attached according to a seventh aspect of the present invention is the method of the fifth or sixth aspect, wherein the surfactant-containing water cleaning step and the rinsing cleaning step are performed alternately. Since it is performed twice, washing and removal of the polychlorinated biphenyls and removal of the surfactant can be reliably performed.

According to the eighth aspect of the present invention, in the method for cleaning a member to which polychlorinated biphenyls are attached, in any one of the first to seventh aspects, an oil cleaning step of cleaning the member with a cleaning oil is performed. The polychlorinated biphenyls remaining on the surface can be more reliably removed by washing.

The ninth invention provides a method for cleaning a member to which polychlorinated biphenyls are attached, according to the eighth invention, wherein the oil cleaning step comprises immersing the member in the oil and irradiating the member with ultrasonic waves. Since this is a step of washing the member, the polychlorinated biphenyls remaining on the member can be more reliably washed and removed.

[0094] According to a tenth aspect of the present invention, in the method for cleaning a member to which polychlorinated biphenyls are attached, in the eighth aspect, the oil cleaning step includes immersing the member in the oil and allowing the member to stand. Since the immersion washing step is performed, the polychlorinated biphenyls remaining on the member can be more reliably washed and removed, and the running cost for the processing can be suppressed.

The method for cleaning a polychlorinated biphenyl-adhered member according to the tenth invention is the method according to any one of the eighth to tenth inventions, wherein the oil is kerosene or low-concentration polychlorinated biphenyls. Since the oil is contaminated, polychlorinated biphenyls remaining on the member can be more reliably washed and removed. In particular, if the oil is contaminated with low-concentration polychlorinated biphenyls, the amount of liquid to be detoxified can be reduced, so that it is possible to further improve the processing efficiency and reduce the processing cost.

The method for cleaning a member to which polychlorinated biphenyls are attached according to a twelfth aspect of the present invention is the method according to any of the first to tenth aspects, wherein the member is immersed in an aqueous alkaline solution to apply a voltage to the member. Is applied to perform an electrolytic cleaning step of cleaning the member, so that even if rust or the like is generated in the member due to aging, it is possible to more reliably wash and remove polychlorinated biphenyls remaining on the member. it can.

In the thirteenth invention, the method for cleaning a member to which polychlorinated biphenyls are attached is characterized in that, in the twelfth invention, the alkaline aqueous solution is an aqueous solution of at least one of sodium hydroxide and sodium carbonate. Further, the hydrothermal decomposition of the polychlorinated biphenyls in the waste liquid after the washing treatment can be performed without any problem.

The cleaning method of a polychlorinated biphenyls-attached member according to the fourteenth aspect of the present invention is the method according to the twelfth or thirteenth aspect, wherein the alkali aqueous solution has an alkali concentration of 5 to 30 wt%. Electrolytic cleaning can be performed efficiently.

The fifteenth invention provides a method for cleaning a member to which polychlorinated biphenyls are attached according to any one of the twelfth to fourteenth inventions, wherein the applied voltage in the electrolytic cleaning step is 4 to 8 V. Therefore, the electrolytic cleaning can be reliably performed.

A sixteenth aspect of the present invention is a device for cleaning a member to which polychlorinated biphenyls are adhered, which is a device for cleaning a member to which polychlorinated biphenyls are adhered. A surfactant-containing water storage means for storing water containing an agent in the cleaning tank, so that the member can be washed with the surfactant-containing water, and the polychlorinated biphenyl can be used without using an organic solvent. Can be washed away. Therefore, the waste liquid treatment after the cleaning treatment can be easily performed at low cost.

A seventeenth aspect of the present invention is directed to the cleaning apparatus for a polychlorinated biphenyls-adhering member according to the sixteenth aspect, wherein the surfactant-containing water storage means comprises a water supply means for supplying water into the cleaning tank. And a surfactant addition means for adding the surfactant in the cleaning tank,
Surfactant-containing water at a specified concentration can be easily stored in the cleaning tank.

An eighteenth aspect of the present invention is directed to the cleaning apparatus of the sixteenth or seventeenth aspect, wherein the ultrasonic irradiating means irradiates an ultrasonic wave to the inside of the cleaning tank. Is provided, cleaning can be reliably performed.

A nineteenth aspect of the present invention provides the apparatus for cleaning a member attached with polychlorinated biphenyls according to any one of the sixteenth to eighteenth aspects, wherein the oil supply means supplies cleaning oil into the cleaning tank. Is provided, the member can be cleaned with the cleaning oil, and the polychlorinated biphenyls can be more reliably cleaned and removed.

[0104] The cleaning apparatus for a polychlorinated biphenyls-adhering member according to a twentieth aspect of the present invention is the apparatus according to any one of the sixteenth to nineteenth aspects, wherein the alkaline aqueous solution is stored in the cleaning tank. Since the means and the voltage applying means for applying a voltage to the member are provided, the member can be electrolytically cleaned with an alkaline aqueous solution, and the polychlorinated biphenyls can be more reliably cleaned and removed.

The cleaning device for a polychlorinated biphenyls-adhering member according to a twentieth invention is characterized in that, in the twentieth invention, the alkaline aqueous solution storage means comprises water supply means for supplying water into the cleaning tank; Since the washing tank is provided with an alkali adding means for adding an alkali or an aqueous alkali solution, it is possible to easily store an aqueous alkali solution having a specified concentration in the washing tank.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a first embodiment of a cleaning apparatus for a polychlorinated biphenyl-adhered member according to the present invention.

FIG. 2 is an explanatory view of a procedure of a first embodiment of a method of cleaning a member to which polychlorinated biphenyls are attached according to the present invention.

FIG. 3 is a schematic configuration diagram of a second embodiment of a cleaning apparatus for a polychlorinated biphenyl-adhered member according to the present invention.

FIG. 4 is an explanatory view of a procedure of a second embodiment of the method of cleaning a member to which polychlorinated biphenyls are attached according to the present invention.

FIG. 5 is an explanatory view of a procedure of a third embodiment of the method of cleaning a member to which polychlorinated biphenyls are attached according to the present invention.

FIG. 6 is a schematic configuration diagram of a fourth embodiment of the apparatus for cleaning a member to which polychlorinated biphenyls are attached according to the present invention.

FIG. 7 is an explanatory view of a procedure of a fourth embodiment of the method of cleaning a member to which polychlorinated biphenyls are attached according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Water 2 Surfactant 3 Surfactant containing water 4 Washing oil 5 Alkaline aqueous solution undiluted solution 6 Alkaline aqueous solution 11 Cleaning tank 12 Ultrasonic generator 13 Water supply pump 14 Surfactant addition device 14a Valve 15 Discharge valve 26 Oil supply pump 47 DC power supply 47a Electrode 47b Connector 48 Alkali addition device 48a Valve 100 Member 101 Fishing support

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Takashi Moribe 5-717-1, Fukahori-cho, Nagasaki-city, Nagasaki Pref. In the Nagasaki Laboratory, Mitsubishi Heavy Industries, Ltd. No. 1 Mitsubishi Heavy Industries, Ltd. Nagasaki Shipyard F-term (reference) 3B201 AA46 AB01 BB03 BB83 BB94 CB01 CC01 CC11 CC21

Claims (21)

[Claims] 1. A method for cleaning a member to which polychlorinated biphenyls are adhered, comprising performing a surfactant-containing water cleaning step of cleaning the member with water containing a surfactant. A method for cleaning biphenyl-attached members. 2. The member according to claim 1, wherein in the surfactant-containing water washing step, the member is immersed in the water containing the surfactant and irradiated with ultrasonic waves to wash the member. A method for cleaning a member to which polychlorinated biphenyls are attached, which is a step. 3. The method according to claim 1, wherein the surfactant is any one of an anionic type, a cationic type, and a non-ionic type. 4. The water according to claim 1, wherein the content of the surfactant is 0.5 to 50 vol.%.
A method for cleaning a member to which polychlorinated biphenyls are adhered. 5. The polychlorinated biphenyls-attached member according to claim 1, wherein a rinse washing step of washing the member with water is performed after the surfactant-containing water washing step. Cleaning method. 6. The polychlorinated biphenyls according to claim 5, wherein the rinsing step is a step of immersing the member in water and irradiating the member with ultrasonic waves to wash the member. A method for cleaning the attached member. 7. The method for cleaning a polychlorinated biphenyl-adhered member according to claim 5, wherein the surfactant-containing water cleaning step and the rinsing step are alternately performed a plurality of times. 8. The method for cleaning a member to which polychlorinated biphenyls are attached according to claim 1, wherein an oil cleaning step of cleaning the member with cleaning oil is performed. 9. The polychlorination according to claim 8, wherein the oil cleaning step is a step of immersing the member in the oil and irradiating the member with ultrasonic waves to wash the member. A method for cleaning biphenyl-attached members. 10. The method according to claim 8, wherein the oil washing step is a step of immersing the member in the oil and leaving the member to soak and wash the member. How to clean parts. 11. The method for cleaning a member attached with polychlorinated biphenyls according to claim 8, wherein the oil is kerosene or oil contaminated with low-concentration polychlorinated biphenyls. . 12. The poly-electrolyte according to claim 1, wherein the member is immersed in an alkaline aqueous solution, and a voltage is applied to the member to perform an electrolytic cleaning step of cleaning the member. A method for cleaning a member to which biphenyl chlorides are attached. 13. The method according to claim 12, wherein the aqueous alkaline solution is an aqueous solution of at least one of sodium hydroxide and sodium carbonate. 14. The method according to claim 12, wherein the alkali aqueous solution has an alkali concentration of 5 to 30 wt%. 15. The method for cleaning a member attached with polychlorinated biphenyls according to claim 12, wherein an applied voltage in the electrolytic cleaning step is 4 to 8 V. 16. An apparatus for cleaning a member to which polychlorinated biphenyls are adhered, comprising: a cleaning tank in which the member is put; and a surfactant-containing water for storing water containing a surfactant in the cleaning tank. An apparatus for cleaning a member to which polychlorinated biphenyls are attached, comprising a storage means. 17. The surfactant-containing water storage means according to claim 16, wherein: the water supply means for supplying water into the cleaning tank; and the surfactant adding means for adding the surfactant into the cleaning tank. A cleaning apparatus for a member attached with polychlorinated biphenyls, comprising: 18. The apparatus for cleaning a member attached with polychlorinated biphenyls according to claim 16, wherein an ultrasonic wave irradiating means for irradiating ultrasonic waves to the inside of the cleaning tank is provided. 19. The apparatus for cleaning a member attached with polychlorinated biphenyls according to claim 16, further comprising an oil supply means for supplying a cleaning oil into the cleaning tank. 20. The cleaning apparatus according to claim 16, further comprising: an alkaline aqueous solution storing means for storing an alkaline aqueous solution in the cleaning tank; and a voltage applying means for applying a voltage to the member. A cleaning device for polychlorinated biphenyls adhered members. 21. The method according to claim 20, wherein the alkaline aqueous solution storage means includes: a water supply means for supplying water into the cleaning tank; and an alkali adding means for adding an alkali or an aqueous alkali solution into the cleaning tank. An apparatus for cleaning a member to which polychlorinated biphenyls are adhered.