JP5632777B2 - Method of cleaning PCB decontaminated equipment - Google Patents

Description

  The present invention relates to a purification method for a PCB-contaminated equipment detoxification facility.

PCB (polychlorinated biphenyl) has been widely used in insulating oils for electrical equipment such as capacitors and transformers in the past because of its excellent stability, nonflammability, and electrical insulation properties. Toxicity is apparent and its use is now prohibited.
In addition, with regard to devices such as capacitors and transformers (hereinafter also referred to as “PCB-contaminated devices”) that restrict their use and already contain PCB-containing insulating oil (hereinafter also referred to as “PCB-contaminated devices”), the following Patent Document 1 shows that As is done, detoxification is done in special facilities with controlled areas.
In the management area of such a PCB-contaminated equipment detoxification facility, a process such as extracting the PCB-containing insulating oil from the PCB-contaminated equipment or disassembling the PCB-contaminated equipment is performed. PCB is contained even though it is concentrated, and the exhaust from the management area to the outside is performed through an activated carbon filter.

By the way, PCB contaminated equipment such as capacitors and transformers has been greatly reduced in the number of objects to be treated by the conventional detoxification process, and in the future, how to end the detoxification process of PCB contaminated equipment will be a new issue. It becomes.
For example, at the time when the detoxification process of the PCB contaminated equipment is finished, PCBs such as a device used for removing the PCB-containing insulating oil from the PCB contaminated device and a device for disassembling the PCB contaminated device are attached to some extent. It is necessary to carry out detoxification processing of the equipment.
In addition, it is necessary to finally detoxify the building itself of the PCB-contaminated equipment detoxification facility where these facilities are installed.
For example, since the partition walls, floors, ceilings, etc. of the management area continue to be exposed to air containing PCB for a long period of time, the concentration that requires treatment before reaching a certain depth from the wall surface. As described above, there is a possibility that PCB has penetrated.
However, there has been almost no study on the removal of PCB from such a wall to purify a PCB-contaminated equipment detoxification facility, and an effective method has not been established.

JP 2003-035044 A

  In view of such problems, an object of the present invention is to provide a method for purifying a PCB-contaminated equipment detoxification facility that can efficiently purify the PCB-contaminated equipment detoxification facility.

In order to solve the above-mentioned problems, the present invention relating to a method for purifying a PCB-contaminated equipment detoxification facility is provided with a liquid paint on the surface of a concrete wall of a PCB-contaminated equipment detoxification facility exposed to PCB-containing air. to form, together with the coating film is cured after curing the coating film scraped surface of the wall, a PCB adhering to the front side of the wall is characterized by removing from said wall.

Partition walls, floors, and ceilings of facilities where PCB decontamination equipment is detoxified are made of various materials. For example, if they are made of a smooth metal plate, impregnated with a cleaning agent Although it is easy to wipe off and remove PCBs that are attached to the surface with a cloth that has been removed, it has fine irregularities formed on the surface, such as general concrete and lightweight cellular concrete (ALC). In the case where the wall surface is formed, it is difficult to exert the PCB removing effect even in the fine recessed portion.
On the other hand, in the present invention, since a liquid paint is used, it is possible to form a coating film excellent in followability to the wall surface.
Then, after the coating film is cured and then peeled off, the PCB adhering to the wall surface can be adhered to the coating film and removed, so that the PCB removal effect can be exhibited even in the fine recessed portion.

In the above case, if a part of the surface of ALC or the like is removed by performing a so-called “sharpening” operation without forming a coating film, fine dust containing PCB As a result, the PCB fixed to the wall surface is diffused, and as a result, a great deal of labor may be required.
On the other hand, if the coating film is formed as in the present invention, even if the “shaving” operation is performed, the ALC fragments are prevented from being finely scattered by the coating film, and the generation of dust can be suppressed. .
Therefore, it can be said that the present invention can implement efficient PCB removal also in this respect.
That is, according to the present invention, the PCB-contaminated equipment detoxification facility can be purified efficiently.

Embodiments of the present invention will be described below.
In the method for purifying a PCB-contaminated equipment detoxification facility according to the present embodiment, a coating film forming step of forming a coating film with a liquid paint on the wall surface of the PCB-contaminated equipment detoxification facility exposed to air containing PCB, A curing process for curing the film and a peeling process for peeling the cured coating film are performed, and the PCB attached to the wall surface is removed in the peeling process.

  In addition, examples of the purification countermeasures constituting the PCB-contaminated equipment detoxification facility include partition walls, floors, ceilings, and the like that are routinely exposed to air containing PCB. In the following, each step will be described by taking as an example the case of purifying a concrete partition wall.

(Coating film formation process)
In the coating film forming step, the coating applied to the wall surface of the partition wall is not particularly limited, but an epoxy resin-based paint, an acrylic resin-based paint, a polyurethane-based paint, or the like can be employed.
The paint may be an aqueous paint in which a polymer component is diluted with an aqueous solvent or an organic solvent in which a polymer component is diluted with an organic solvent.
When a water-based paint is used as the paint, the working environment of the coating film forming operation can be made cleaner than when an organic solvent-based paint is used.
On the other hand, when an organic solvent-based paint is used, it is possible to expect an action of extracting PCB penetrating into the interior from the wall surface to the surface side by the organic solvent contained in the paint.

In addition, in this embodiment, although explained in full detail in the back | latter stage, the peeling process which peels this coating film from a partition wall in the state which shaved the surface part of the partition wall and made the wall surface adhere to the coating film side is implemented.
Since this partition wall shaving is performed by giving a blow from above the coating film, it is preferable to form a hard coating film with excellent impact force transferability. Among these, it is preferable to employ an epoxy resin-based paint that can form a relatively hard coating film.

Moreover, as a coating material to be used, it is preferable that it is colored in a different hue from the wall surface so that the application region can be grasped.
By coloring the paint in a color different from that of the wall in this way, even if a large number of concrete pieces are generated as a result of shaving the surface of the partition wall in the subsequent peeling step, which concrete piece is the partition. Whether the wall surface of the wall has been formed can be grasped by the adhesion of a coating film having a different hue, and the effect that a concrete piece having a high PCB concentration can be easily grasped is also exhibited.

The coating film formed with this paint is difficult to peel off unless it has a certain thickness. On the other hand, even if the thickness is excessively thick, the time required for curing may be prolonged.
For this reason, although depending on the material of the paint used, the dry thickness of the coating film to be formed is usually about 0.2 mm to 2 mm.

If the viscosity of the paint is low, it is difficult to ensure the thickness as described above. On the other hand, if the viscosity is excessively high, wetting and spreading to the wall surface is insufficient, and the wall surface is not sufficiently tracked. There is a risk of becoming.
For this reason, it is sufficient that the paint has a viscosity at the time of construction. The viscosity of the paint is, for example, 1 Pa · s or less at a temperature of 40 ° C., and further about 0.01 Pa · s to 0.1 Pa · s. It is said.
In addition, the viscosity here is intended to be measured by a viscometer for non-Newtonian fluid such as a rotational viscometer.

  As a method for applying the paint to the partition wall, a general method such as roller coating, brush coating, spray coating, or the like can be employed.

(Curing process)
The coating film formed in the coating film forming step may be accelerated by using a heater capable of radiant heating or a hot air heater, if necessary, until the cured coating film is formed. It may be left at room temperature and simply provided with a certain curing period.
In addition, if necessary, after the curing step is performed and the coating film is cured, the coating film may be applied again to increase the thickness of the coating film.
Furthermore, you may make it aim at suppression of scattering of the concrete piece in the peeling process in a latter stage, such as sticking an adhesive sheet on the cured coating film.

(Peeling process)
As described above, in the present embodiment, the peeling step is performed in the form of cutting the surface of the partition wall.
That is, in this embodiment, the step of peeling the cured coating film from the partition wall together with the surface portion of the partition wall is performed, and from the PCB adhering to the wall surface of the partition wall to the PCB penetrating into the interior Is also removed in a form adhered to the coating film.
The peeling process by such an aspect can be implemented using construction tools, such as a chipper to which a chisel or a rod is attached.
In such a case, for example, a sheet material such as a construction sheet is arranged so as to be opposed to each other at a position 1 to 2 m away from the partition wall so as not to scatter fine concrete pieces around. It is preferable to perform an exfoliation process with an operator.

  In this exfoliation process, if the surface of the partition wall is cut to an excessively deep position, the amount of the object to be processed is increased more than necessary. Then, it may be cut to a depth of 5 mm to 10 mm.

After this peeling step, PCB is sufficiently removed from the partition wall, and whether the partition wall is sufficiently purified is determined by measuring the PCB concentration by the member sampling test method for the member after peeling, and 0.01 mg / Confirm that it is less than kg.
It can be confirmed by such a method.
In addition, what is necessary is just to make the processing target object which mixed the coating film and concrete obtained at a peeling process thermally decompose PCB contained using a plasma melting furnace etc., and to make it harmless by making it slag.

The method for purifying a PCB-contaminated equipment detoxification facility according to the present embodiment is not necessarily performed only when the entire PCB-contaminated equipment detoxification facility is demolished. Even in such a case, implementation is possible.
In other words, the shaved part can be backfilled with new concrete, and the room partitioned by this partition wall can be used again as an unmanaged area, and conversely, it was a room and a managed area that were unmanaged areas. It is also possible to adopt the present invention even when a part contaminated with PCB is once removed from the partition wall when the partition wall between the rooms is removed and newly used in a state where two rooms are connected. is there.

Further, in this embodiment, the partition walls are targeted for purification, but the present invention also intends to remove PCB attached to the ceiling or floor wall.
Furthermore, in this embodiment, the surface portion of the wall that is the purification object is attached to the coating film side to peel the coating film from the purification object. For example, at the interface between the coating film and the wall surface, The case where the coating film is peeled is also within the range intended by the present invention in removing PCB by attaching it to the coating film.

In the present embodiment, the peeling step is performed by scraping the wall surface (partition wall) surface. However, the present invention is not limited to this, and only the paint applied to the surface may be peeled off. In particular, if the wall surface is a non-impregnated member, it is exposed to the PCB and only the surface adheres to it, so it is sufficient to remove only the PCB firmly adhered to the surface.
That is, since the PCB on the wall surface is adsorbed by the paint by applying the paint, only the coating film formed by this paint needs to be peeled off.
Also, the peeling method is not limited to peeling by impact, and when the coating film has flexibility, a part of the coating film is cut up or the edge of the coating film is turned up and gripped. The coating may be peeled off by forming a margin and pulling the gripping margin away from the wall surface. According to such a method, scattering at the time of pulverizing the coating can be suppressed.
In addition, the present invention can be implemented with various modifications to the above-exemplified methods, and the matters relating to the PCB decontamination technology are adopted in the present invention as long as the effects of the present invention are not significantly impaired. Is possible.

Claims (4)

A coating film is formed with a liquid paint on the surface of a concrete wall of a PCB-contaminated equipment detoxification facility exposed to PCB-containing air, and after the coating film is cured , scraped surface cleaning method of PCB contaminated equipment detoxifying facility and removing the PCB adhering to the front side of the wall from the wall. The method for purifying a PCB-contaminated equipment detoxification facility according to claim 1, wherein the surface of the wall is shaved by arranging a sheet material so as to face the wall surface so that the scraped concrete can be prevented from scattering. The method for purifying a PCB-contaminated equipment detoxification facility according to claim 1 or 2, wherein the liquid paint is an epoxy resin-based paint. The method for purifying a PCB-contaminated equipment detoxification facility according to any one of claims 1 to 3, wherein the liquid paint is colored in a color different from a wall to which the liquid paint is applied.