JP5654907B2 - Electric equipment regeneration method and electric equipment regeneration apparatus - Google Patents

Description

  The present invention relates to a method for regenerating an electrical device and a device for regenerating the electrical device, and more particularly to a method for regenerating an electrical device using an insulating oil containing polychlorinated biphenyl and a device for regenerating the same.

  Polychlorinated biphenyl (hereinafter referred to as “PCB”) is excellent in stability, nonflammability, and electrical insulation, and thus has been widely used in the past as an insulating oil in the construction of electrical equipment such as capacitors and transformers. It was. At present, this PCB is prohibited from being produced or used for new reasons due to its indegradability and toxicity. Electrical devices such as capacitors and transformers that use insulating oil containing PCB are collected and stored, and are required to be processed quickly.

  This capacitor and transformer are accommodated in the housing in a state in which the capacitor element and transformer coil are immersed in insulating oil containing PCB. In the treatment, the insulating oil containing PCB is drained and then crushed. A method of cleaning and recovering valuable materials such as iron scraps and copper scraps is widely used.

  On the other hand, it is possible to recycle the electrical equipment by detoxifying the electrical equipment by encapsulating insulating oil that does not substantially contain PCB in the electrical equipment after draining without performing such crushing. It is described in Document 1 and the like.

JP 2006-122767 A

However, a method for regenerating electrical equipment by refilling with insulating oil that does not contain PCB has not been sufficiently studied so far, and a method for improving the processing efficiency in the recycling method is still established. No.
An object of the present invention is to improve the processing efficiency in such a method for regenerating an electric device and to provide a reproducing apparatus that can regenerate the electric device with excellent efficiency.

The present invention in the method for regenerating an electrical device for solving the above-mentioned problem is the following, after carrying out the oil extraction step of taking out the insulating oil from the electrical device in which the insulating oil containing polychlorinated biphenyl is enclosed in a housing, A method for regenerating an electrical device, wherein a new insulating oil having a polychlorinated biphenyl concentration of 0.5 ppm or less is enclosed in a housing so that the electrical device is rendered harmless and can be reused. After the step, a diagnostic step of diagnosing the soundness of the casing is performed by holding the inside of the electric device in a reduced pressure state.

In addition, the present invention in an electrical equipment regenerator for solving the above-mentioned problems is that after performing the oil extraction step of taking out the insulating oil from the electrical equipment in which the insulating oil containing polychlorinated biphenyl is sealed in the housing. An electrical equipment regenerator that renders the electrical equipment harmless and reusable by enclosing a new insulating oil having a polychlorinated biphenyl concentration of 0.5 ppm or less in the casing. Then, after the oil draining step, a decompression mechanism for bringing the electrical device into the decompressed state so that the soundness of the housing can be diagnosed by holding the interior of the electrical device in the decompressed state, And a pressure measuring mechanism for measuring the pressure inside the electric device being held.

  In this specification, the term “new insulating oil” means that not only unused (new) insulating oil but also insulating oil containing PCB is rendered harmless after industrial production from crude oil. It is used with the intention of including insulating oil that has been treated and newly made available as insulating oil.

In the method for regenerating an electrical device according to the present invention, after performing an oil extraction process for extracting the insulating oil containing PCB from the electrical device, the inside of the electrical device is maintained in a reduced pressure state to thereby maintain the soundness of the casing. A diagnosis process for diagnosis is performed.
In addition, the electric device regeneration apparatus of the present invention includes a pressure reducing mechanism for reducing the pressure inside the electric device, and a pressure measuring mechanism for measuring the pressure inside the electric device held in the pressure reduced state. And are provided.
Accordingly, it is possible to grasp the damage of the casing or the like based on the pressure change inside the electric device, and to diagnose the soundness of the casing.
That is, according to the present invention, since the soundness of the casing is grasped prior to the sealing of the new insulating oil, etc., the sealing work can be performed by detecting an abnormality of the casing after sealing the new insulating oil. And the like can be prevented from being wasted.
For this reason, according to the present invention, it is possible to improve the processing efficiency in the regeneration of the electrical equipment.

The schematic block diagram which shows the structure of the reproducing | regenerating apparatus of the electric equipment of this embodiment. Sectional drawing which shows the principal part which shows the washing | cleaning method inside an electric equipment. The schematic block diagram which shows the structure of the reproducing | regenerating apparatus of the electric equipment of other embodiment.

First, a reproduction apparatus for an electric device will be described with reference to the drawings.
FIG. 1 shows the configuration of an apparatus used for the method for regenerating an electrical device according to this embodiment, and an electrical device using an insulating oil containing polychlorinated biphenyl (hereinafter also referred to as “PCB-containing insulating oil”). As an example, a transformer is reproduced.
FIG. 2 is a cross-sectional view of the main part showing an aspect of oiling into the transformer and oil removal (washing) from the transformer.

As shown in FIG. 1, the electrical apparatus regeneration apparatus 1 according to this embodiment includes a decompression mechanism 2 for bringing the electrical equipment into the decompressed state, and a pressure inside the electrical equipment in the decompressed state. A pressure measuring mechanism 3 for measuring for a certain period is provided.
Further, in the electrical apparatus regeneration apparatus 1 according to the present embodiment, the PCB-containing insulating material 4 that makes the PCB-containing insulating oil taken out from the transformer TR harmless, the harmless insulating oil, and the like are used. A cleaning mechanism 5 is provided for cleaning the inside of the transformer TR after the insulating oil is extracted.

Although not shown in detail in the figure, the transformer TR has a substantially rectangular parallelepiped container body having an opening at the top as its casing, and a rectangular plate-like lid body for closing the opening of the container body. The container main body and the lid body are fixed via a sealing material disposed on the peripheral edge of the opening of the container main body.
The lid is formed with a supply / exhaust port for supplying insulating oil to the inside of the transformer TR or for extracting the insulating oil from the inside, and the supply / discharge port is usually a cap member. Is blocked.

The reproduction apparatus 1 according to the present embodiment is formed as a device constituting the decompression mechanism 2 so that it can be inserted into the lid of the transformer TR from which the cap member has been removed through the supply / exhaust port. An oil absorption pipe 11 having a length extending to the bottom of the main body and a suction pump 10 for sucking and extracting the PCB-containing insulating oil from the inside of the transformer TR through the oil absorption pipe 11 are provided.
The oil absorption pipe 11 is fixed to the lid body with a tip end having an oil absorption port positioned at the bottom of the container body, and the PCB containing insulating oil is discharged out of the transformer TR by the suction pump 10. The supply / exhaust port is fixed in a sealed state so that the inside of the transformer TR can be in a reduced pressure state.

In addition, as a device constituting the decompression mechanism 2, the reproducing apparatus 1 of the present embodiment is provided with a vacuum pump 20 for further decompressing the interior of the transformer TR as necessary.
The vacuum pump 20 may be a general rotary type or reciprocating type, and is not particularly limited. For example, a vacuum of about 10 ⁻³ Pa for a small sealed container or the like. What can give a degree etc. can be employ | adopted as a vacuum pump in this embodiment.

  The suction pump 10 is arranged in the middle of the path of the PCB-containing insulating oil transfer piping portion L1 for transferring the PCB-containing insulating oil sucked by the oil absorption pipe 11 to the detoxification mechanism 4, and the vacuum pump 20 Further, upstream of the suction pump 10 (oil absorption pipe 11), it is connected to the branch piping portion L2 branched from the PCB-containing insulating oil transfer piping portion L1 via the three-way valve V1.

That is, when the pressure reducing mechanism 2 is not formed in the transformer TR enough to confirm the soundness of the transformer casing after the PCB-containing insulating oil is removed, the three-way valve The flow path is switched to the branch pipe portion L2 side by V1, and the vacuum pump 20 can further reduce the pressure.
The exhaust gas from the vacuum pump 20 is separately processed by removing / detoxifying PCB vapor and the like which is supplied to an apparatus for exhaust gas treatment.

In addition, the PCB-containing insulating oil transfer piping section L1 has a sample sampling location (sampling location) so that the PCB concentration of the PCB-containing insulating oil can be confirmed by sampling the insulating oil on the upstream side of the three-way valve V1. ) 12 is provided.
That is, the decompression mechanism 2 is not only configured to be able to decompress the inside of the transformer TR to a predetermined degree of vacuum, but also performs sampling when taking out the PCB-containing insulating oil outside the transformer, The processing condition in the detoxification mechanism 4 can be determined by the PCB concentration of the oil.

The pressure measuring mechanism 3 is configured using a vacuum gauge VC for measuring a reduced pressure state (degree of vacuum) inside the transformer TR.
The regenerator 1 according to the present embodiment contains the PCB by closing the open / close valve V2 provided at a location further upstream than the three-way valve V1 after the pressure reduction mechanism 2 performs pressure reduction inside the transformer. It is formed so that the pressure inside the transformer can be prevented from changing through the insulating oil transfer piping section L1, and the soundness of the casing of the transformer TR is judged by observing the change of the vacuum gauge VC. Shaped to get.

In the present embodiment, the detoxification mechanism 4 performs a detoxification process on the PCB-containing insulating oil supplied from the PCB-containing insulating oil transfer piping section L1 by a catalytic hydrogen reduction method. The catalytic hydrogen reduction method And an ammonia-containing water storage tank 40 for adding ammonia-containing water before supplying the PCB-containing insulating oil to the reactor 30.
Further, the detoxification mechanism 4 is further provided with a heater 31 for heating before introducing the PCB-containing insulating oil to which ammonia-containing water is added into the reactor 30.

  Further, the detoxification mechanism 4 includes ammonia-containing water so that the ammonia-containing water stored in the ammonia-containing water storage tank 40 can be added to the PCB-containing insulating oil that flows through the PCB-containing insulating oil transport pipe L1. A water conveyance piping section L4 is provided, and the ammonia-containing water conveyance piping section L4 has one end connected to the ammonia-containing water storage tank 40 and the other end upstream of the suction pump 10 containing the PCB. It is connected to the insulating oil transfer piping part L1.

For example, a reactor having a nickel molybdenum catalyst can be used as the reactor 30, and PCB is dehalogenated and supplied with a double bond, an aldehyde group, and a carbonyl group generated by deterioration of insulating oil. Those that can be hydrogenated with the hydrogen gas thus formed can be used.
Usually, in such a reactor 30, polychlorinated biphenyl and the like are hydrogenated (dehalogenated) to be changed to biphenyl, phenylcyclohexane, bicyclohexyl and the like, and hydrogen chloride generated by the dehalogenation, etc. Is neutralized with ammonia to form ammonium chloride.

The detoxification mechanism 4 in this embodiment is included in the insulating oil from which PCB is removed (dehalogenated) by the hydrogenation reaction in the reactor 30 (hereinafter also referred to as “detoxified insulating oil”). A cleaning tank 50 for removing ammonium chloride and an oil / water separator 60 for removing water contained in the detoxified insulating oil after passing through the cleaning tank 50 are provided.
In the washing tank 50, specifically, water, sodium hydroxide, or the like is added to dissolve ammonium chloride, hydrogen sulfide, or the like.
In addition, the waste water discharged | emitted from this oil-water separator 60 will be supplied to the apparatus separately provided for waste water treatment, and will be processed.

The reactor 30, the washing tank 50, and the oil / water separator 60 are connected to each other by a detoxified insulating oil transport pipe L5 so that the detoxified insulating oil can flow down in order. Sampling the detoxified insulating oil after passing through the oil-water separator 60 in the insulating oil transfer piping section L5 and confirming whether the PCB concentration of the detoxified insulating oil is 0.5 ppm or less stipulated by law A sampling point 41 is provided so as to be able to.
In Japan, since the PCB concentration allowed by law is set to 0.5 ppm or less, by setting the PCB concentration to 0.5 ppm or less, it can be reused as insulating oil for transformers and capacitors.
In other countries, such as the United States and European Union countries, the specified value for PCB concentration is often set higher than in Japan, and by clearing this standard value of 0.5 ppm or less, not only Japan but also other countries Can be a reusable reproduction transformer.
However, when the recycling method is used, the PCB concentration does not necessarily have to be 0.5 ppm or less when reusing in foreign countries, and the allowable PCB concentration according to the legal system of each country. If the hydrogenation reaction is carried out until it becomes, it can be reused as insulating oil for electrical equipment.

The cleaning mechanism 5 is such that the PCB concentration is reduced to 0.5 ppm or less, and further, salt and moisture are further removed from the detoxified insulating oil in which the oxidative degradation sites such as aldehyde and carbonyl are refreshed, and the transformer oil is again removed. Insulating oil adjusted to a usable condition (hereinafter also referred to as “regenerated insulating oil”) can be used as a cleaning agent for cleaning the inside of the transformer after oil removal, and stores the regenerated insulating oil. A regenerated insulating oil storage tank 80 is provided.
The regenerated insulating oil storage tank 80 is formed so that the regenerated insulating oil can be supplied from the oil / water separator 60 through the regenerated insulating oil transfer piping L6 by the regenerated insulating oil transfer pump 70.
And the washing | cleaning mechanism 5 has the washing | cleaning-agent supply piping part L7 and the washing | cleaning-agent supply pump 100 so that this regeneration insulating oil can be supplied to the transformer TR after deoiling as a washing | cleaning agent.
This cleaning agent supply piping part L7 is connected to the oil absorption pipe 11 or the PCB-containing insulating oil transfer piping part L1, and performs washing by alternately performing oil injection into the transformer and oil removal from the transformer ( 2 (see FIG. 2A), for example, circulating cleaning in which the cleaning agent is sucked from the oil absorption pipe 11 while being opened at the supply / discharge port and injecting the cleaning agent from the cleaning agent supply piping portion L7. (See FIG. 2B).

In addition, the cleaning mechanism 5 is a new insulation that substantially does not contain PCB for the case where a higher quality insulating oil than the regenerated insulating oil is required as the insulating oil finally sealed in the transformer. A virgin insulating oil storage tank 90 for storing oil (hereinafter also referred to as “virgin insulating oil”) is provided, and the cleaning mechanism 5 removes oil from the virgin insulating oil storage tank 90 through the cleaning agent supply pipe portion L7. It is formed so that virgin insulating oil can be supplied to the later transformer TR.
In addition, as said virgin insulating oil, a commercially available thing can be used as high-pressure insulating oil etc., for example, JIS C2320 1 type 2 insulating oil etc. can be used.
In this embodiment, this virgin insulating oil can also be used as a cleaning agent. However, from the viewpoint of cost, it is preferable to use the regenerated insulating oil as a cleaning agent.

The cleaning mechanism 5 of the present embodiment is provided with a heating mechanism 110 so that the cleaning agent (regenerated insulating oil or the like) in the transformer can be heated.
That is, the cleaning mechanism 5 of the present embodiment is formed so that the heated regenerated insulating oil can be used for cleaning the inside of the transformer TR.
The heating mechanism 110 includes a pump 111 for extracting the cleaning agent from the transformer and returning it to the transformer again, and a heating device 112 provided in the cleaning agent circulation path by the pump 111.
The heating device 112 includes a heat exchanger that exchanges heat with the cleaning agent, a sheathed heater that is provided in the flow path of the cleaning agent, and a jacket heater that heats the piping through which the cleaning agent flows from the outside. The thing of various aspects, such as these, is employable.
By adopting such a configuration, the temperature of the cleaning agent can be gradually increased while circulating, so that the cleaning agent can be safely heated to prevent overheating and the thermal deterioration of the cleaning agent. Can also prevent.
Therefore, it becomes possible to clean the inside of a huge transformer safely and efficiently.
In addition, it is good also as a structure which replaces with such a heating mechanism 110, accommodates a heating apparatus like a throwing heater in a transformer, and heats an internal cleaning agent with this heating apparatus.
Further, when it is not necessary to control the temperature of the cleaning agent, or when the transformer itself is small and the heat capacity is small, the cleaning oil may be heated in advance and injected with heated oil before being injected into the transformer.
In this case, as shown in FIG. 3, a heating device (for example, a heat exchanger 112 ′) may be arranged in a path for supplying the regenerated insulating oil to the transformer.
Further, if the heat exchanger 112 ′ is disposed in the path for supplying the transformer, a separate path from the transformer TR to the cleaning agent supply pump 100 is provided, and the cleaning agent is circulated using the cleaning agent supply pump 100. Thus, a mechanism that replaces the heating mechanism 110 in FIG. 1 may be configured.
Although not described in detail here, the above-exemplified configurations include conventional devices for detoxifying difficult-to-decompose halides such as PCBs, and other devices used to configure a regenerator for electrical devices. In addition to the above, it is possible to provide a playback device for an electrical apparatus according to the present invention.

Next, a method for reproducing the transformer TR using such a reproducing apparatus 1 will be described.
First, the cap member provided on the lid of the transformer TR is removed to open the supply / discharge port, the oil absorption pipe 11 is inserted into the transformer TR through the supply / discharge port, and the tip of the oil supply pipe 11 is inserted into the container body of the transformer TR. The gap between the oil absorbing pipe 11 and the supply / exhaust port is closed at the time when the vicinity of the bottom of the oil is reached.
In this state, the on-off valve V4 on the cleaning agent supply piping L7 side is closed, the on-off valve V2 on the PCB-containing insulating oil transfer piping L1 side is opened, and the three-way valve V1 is connected to the suction pump 10 The suction pump 10 is operated such that the side of the suction pump is open.

And the oil extraction process which takes out the PCB containing insulating oil accommodated in the inside of transformer TR with the suction pump 10 out of the transformer TR is performed, and the extracted PCB containing insulating oil is supplied to the harmless mechanism 4.
At this time, if necessary, the PCB-containing insulating oil taken out from the transformer TR for the purpose of setting the conditions of the detoxifying process in the detoxifying mechanism 4 is sampled from the sample extraction location 12 in the PCB-containing insulating oil transfer piping section L1. PCB concentration can also be measured.
However, in the case where it is possible to set the conditions for detoxification processing without performing such measurement, the sampling is not required. For example, the insulation used for the transformer from the model number of the transformer to be reproduced, etc. Sampling is not necessary until oil information is available.

  In this oil removal process, since the internal PCB-containing insulating oil is discharged by the suction pump 10 in a state where the transformer TR is sealed, the inside of the transformer TR is filled by the volume of the PCB-containing insulating oil taken out. The pressure is reduced.

Here, when it is difficult to ensure a sufficient degree of vacuum for diagnosing the soundness of the casing, which will be described later, by simply discharging the PCB-containing insulating oil, the vacuum pump 20 is operated and the vacuum pump 20 is operated. What is necessary is just to switch the three-way valve V1 to the said vacuum pump 20 side, and to implement further pressure reduction.
For example, even when the vacuum pump 20 is operated for a certain time, a change in the degree of vacuum is hardly observed during that time, and when the vacuum gauge VC confirms that the inside of the transformer TR is in a stable reduced pressure state. The on-off valve V2 of the PCB-containing insulating oil transfer pipe L1 is closed to prevent air from flowing into the transformer from the PCB-containing insulating oil transfer pipe L1 or the cleaning agent supply pipe L7.

Thereafter, a diagnosis process is performed in which the state of the casing is determined by maintaining this state for a certain time (for example, 1 hour) and observing a change in the degree of vacuum with the vacuum gauge VC.
This will be described in more detail. After the internal pressure of the transformer TR is reduced to a predetermined reduced pressure state by the pressure reducing mechanism 2 and the on-off valve V2 is closed, the degree of vacuum read by the vacuum gauge VC is lowered (inside of the transformer TR When the atmospheric pressure of the air pressure rises), it can be determined that the outside air is flowing into the transformer from any part of the casing.
If such a decrease in the degree of vacuum is observed by the vacuum gauge VC, the gas inflow portion is identified and repaired depending on the state of the decrease in the degree of vacuum, or the transformer TR is regenerated. It is possible to select whether to give up and shift to regeneration of another transformer.

By carrying out this diagnostic process, it is possible to prevent the trouble of recycling and waste of materials due to the discovery of defects in the housing after regeneration, etc., and in addition, depending on the situation of reduced vacuum Since the countermeasure can be selected, the regeneration processing of the electric device can be performed more efficiently.
For example, if the decrease in vacuum level changes slowly, the sealing material may be deteriorated. If the rate of decrease in vacuum level is relatively fast, cracks or holes in the container body or lid Is considered to be formed.
Thus, the inflow location of external air can be grasped to some extent by the degree of vacuum reduction.
Furthermore, when the rate of decrease in the degree of vacuum is remarkably high, it can be determined that the repair is difficult, and it is preferable to give up the regeneration and shift to a regeneration process of another transformer.

In addition, although this diagnosis process depends on the type and size of the electrical equipment that is the target of grasping the soundness of the casing, the inside of the electrical equipment is usually any vacuum in the range of 1 kPa to 100 kPa. After that, the reduced pressure state is maintained for any period within the range of 1 hour to 24 hours, preferably 2 hours to 12 hours, and the soundness of the casing is observed by observing the degree of vacuum during that period. Can be grasped.
Note that the gas contained in the insulating oil may be released at the beginning when it is kept in a reduced pressure state, and this may not keep the reduced pressure state. After that, it is preferable to perform an operation of further reducing the pressure and removing the gas contained in the insulating oil and the gas (gas) held in the device by holding the reduced pressure state for a certain period of time. In addition, although it does not specifically limit as this holding | maintenance period, 20 minutes or more and 2 hours or less, Preferably 1 hour or more and 2 hours or less are preferable.

For example, if the transformer has an internal volume of about 2 m ³ , the internal pressure is usually reduced by about 50 kPa (that is, the internal pressure is normal pressure −50 kPa = 51.3 kPa) and maintained in that state for 1 hour. Check the internal pressure later.
At this time, the internal pressure may be restored to about 60 kPa. In that case, the internal pressure is reduced to about 50 kPa by reducing the pressure again, and the internal pressure is almost changed by holding again in this state for 1 hour. If not, the inside of the interior can be reduced to 50 kPa again to carry out the diagnostic process.
In the diagnosis process, if the leak amount is 10 ⁻⁶ Pa · m ³ / s or less, it can be determined that the state is sound, and the leak amount is greater than 10 ⁻⁶ Pa · m ³ / s and 10 ² Pa · m ^3. If it is / s or less, it can be determined that the soundness can be obtained by replacing the packings.
On the other hand, when the leak amount is larger than 10 ² Pa · m ³ / s, it can be determined that the repair is difficult.

In addition, the sensitivity in the soundness judgment of a housing | casing can be improved, so that the vacuum degree inside transformer TR is raised (it reduces pressure).
On the other hand, if the degree of vacuum is increased too much, the oil of the vacuum pump 20 may be contaminated by PCB vapor or the like, and the load in the exhaust gas treatment of the vacuum pump 20 may be increased.
For this reason, for example, when the PCB concentration of the PCB-containing insulating oil used in the transformer TR is 100 ppm or more, a pre-cleaning process is performed to clean the inside of the transformer TR before performing the diagnostic process. It is preferable to do.
Further, when a trace amount of PCB-contaminated insulating oil is used such that the PCB concentration of the PCB-containing insulating oil is 100 ppm or less, the necessity of performing the preliminary cleaning step is low.

This preliminary cleaning step can be performed, for example, using the regenerated insulating oil as a cleaning agent, and can be performed using the virgin insulating oil as a cleaning agent as necessary.
Specifically, after the oil removal step, the on-off valve V2 of the PCB-containing insulating oil transfer piping section L1 is closed, and the on-off valve V4 on the side of the cleaning agent supply piping section L7 is opened to regenerate by the cleaning agent supply pump 100. This can be implemented by supplying regenerated insulating oil from the insulating oil reservoir 80 into the transformer TR.

In this pre-cleaning step, after the cleaning agent is injected into the transformer TR, the pressure between the members is reduced to remove bubbles between the members so that the injected cleaning agent can easily penetrate into details, and the PCB remaining inside the transformer TR. Can be efficiently removed.
As described above, in order to increase the cleaning efficiency, a decompression step by the vacuum pump 20 may be performed after the cleaning agent is injected.
In addition, the cleaning agent used in the preliminary cleaning step may be appropriately heated (for example, a temperature of 40 ° C. or higher and 120 ° C. or lower ) by using the heating device 112 (heat exchanger 112 ′) or the like. It is preferable in terms of efficiency.
By heating the cleaning agent in this manner, it is possible to improve the permeability due to a decrease in viscosity, improve the solubility, and also exert the effect of promoting the foaming.

The specific cleaning method to be performed in the preliminary cleaning step is not particularly limited, and a method of vibrating / rotating the transformer TR filled with regenerated insulating oil or performing internal stirring with a stirrer Is mentioned.
In addition, a bypass pipe and a pump that bypass the PCB-containing insulating oil transfer piping section L1 and the cleaning agent supply piping section L7 are separately provided, and the cleaning agent is transferred from the cleaning agent supply piping section L7 to the transformer TR, PCB-containing insulating oil transfer. It is also possible to recirculate the cleaning agent supply piping portion L7 again through the piping portion L1 and the bypass piping to perform circulation cleaning.
Then, the cleaning agent is sampled from the sample extraction location 12 and the cleaning effect is confirmed by measuring the PCB concentration of the cleaning agent. If it is determined that the desired preliminary cleaning is performed, the cleaning TR is accommodated in the transformer TR. Similarly to the PCB-containing insulating oil that was initially contained, the cleaning agent that has been used may be supplied to the detoxification mechanism 4 by the suction pump 10 to perform the detoxification process by hydrogenation (dehalogenation).

After the preliminary cleaning process, the diagnostic process is performed, and for the case where the soundness of the casing is confirmed, for example, recycled insulating oil, virgin insulating oil, or a mixed oil thereof is sealed as new insulating oil Thus, the transformer TR can be reproduced.
The PCB-containing insulating oil whose PCB concentration originally exceeded the national standard value (0.5 ppm) was detoxified by the detoxification mechanism 4 so that the PCB content was 0.5 ppm or less. Using the obtained regenerated insulating oil as an insulating oil that is newly sealed in a regenerative transformer is more cost effective for regenerating than using virgin insulating oil as a new insulating oil, and from the viewpoint of effective use of regenerated insulating oil. To preferred.
On the other hand, it is possible to enclose virgin insulating oil as new insulating oil from the viewpoint of ensuring the reliability of the regenerative transformer, although it has some disadvantages in terms of cost.

  At this time, the deep part of the equipment inside the transformer is not sufficiently cleaned in the preliminary cleaning, and after insulating the regenerated insulating oil or virgin insulating oil as a new insulating oil, the PCB exudes from the inside to insulate it. In the case where the PCB concentration of the oil may exceed 0.5 ppm, a cleaning step for cleaning the inside of the transformer TR may be performed separately after the diagnosis step.

This cleaning step can be performed in the same manner as the preliminary cleaning step, and includes, for example, a method of cleaning the inside of the transformer TR with the regenerated insulating oil that has been rendered harmless so that the PCB content is 0.5 ppm or less. It is done.
As a specific method, for example, a method of once vibrating and rotating the transformer TR enclosing the regenerated insulating oil, or performing internal stirring with a stirrer can be employed.
Moreover, the method etc. which carry out circulation washing | cleaning similarly to a preliminary washing process are also employable.

  In this way, after the diagnostic process, by further performing the cleaning process, it is possible to suppress the PCB from remaining inside.

Then, for example, the insulating oil is sampled from the sample sampling point 12 or the like during the circulation cleaning, and a graduation determination is performed to determine whether the PCB concentration is a predetermined concentration (for example, 0.5 ppm) or less, and a pass determination is obtained. At this point, the circulation is stopped and the supply / exhaust port of the housing is closed to complete the regeneration of the transformer.
At this time, it is preferable to carry out the moisture measurement step together. Insulating oil containing PCB is often used in electrical equipment that is used at a relatively high voltage. High voltage applications (for example, AC 600 V or more, DC 750 V or more, which were originally used for regenerating this transformer) In order to ensure reliability at high voltage, the moisture measurement step is performed to adjust the moisture content to a predetermined level or less. It is preferable.

  Further, in the present embodiment, the oil removal process is performed using the pressure reducing mechanism, but the present invention may also be provided when a mechanism for performing the oil removal process is provided separately from the pressure reducing mechanism that causes the inside of the electrical equipment to be in a reduced pressure state. Is the intended range.

Furthermore, in this embodiment, the case where the pre-cleaning process before the diagnostic process and the cleaning process after the diagnostic process are performed is illustrated in that the PCB can be removed more reliably. Is not an essential requirement in the present invention.
In this preliminary cleaning process and cleaning process, an example of using a recycled insulating oil (possibly virgin insulating oil) that can be used as an insulating oil after being finally enclosed in a regenerative transformer as a cleaning agent is illustrated. However, if necessary, either a pre-cleaning step or a cleaning step may be performed using a solvent having excellent compatibility with the PCB-containing insulating oil such as normal paraffin as a cleaning agent.
In the case where the regenerative transformer is used as a high-voltage transformer, it is preferable to use the regenerated insulating oil as a cleaning agent as exemplified in the present embodiment because there is a possibility that normal paraffin or the like may be mixed. .
In addition, when using a cleaning agent other than insulating oil, it may be necessary to separately provide a system for enclosing the insulating oil and a system for circulating the cleaning agent. It can be said that the use is preferable because the device configuration can be made simpler.
In this embodiment, the diagnostic process is performed after the pre-cleaning process, but there is a defect (such as a minute hole or crack) in the transformer housing, and the part is clogged with dust or sand, and the appearance is defective. Even when such a phenomenon is not observed, dust, sand, and the like are removed by performing preliminary cleaning, so that it is easy to find defects. In addition, there is an effect that it becomes easier to find such a defect in the subsequent diagnosis process.
Further, in this embodiment, the insulating oil is injected in a sealed state into the housing that has been subjected to the diagnostic process in advance, but this can prevent moisture in the air from entering the device. Play.

In the present embodiment, cleaning is performed with the cleaning agent in a heated state in order to achieve excellent cleaning properties, but cleaning may be performed at room temperature.
Further, in the present embodiment, the location where oil is to be removed and the location where oil is to be lubricated are substantially the same location, but the present invention is not limited to this, and as a configuration in which oil is removed and lubricated from different locations using piping provided in the transformer. Also good.
In the present embodiment, the insulating oil extracted from the transformer is directly supplied to the detoxifying mechanism. However, the present invention is not limited to this, and a contaminated oil storage tank for storing contaminated oil (reference numeral 200 in FIGS. 1 and 3). It is good also as a structure which provides and stores in this. In this case, when a certain amount of the contaminated oil stored in the contaminated oil storage tank 200 is stored, it is detoxified by a separate detoxification processing facility, and then the detoxified processing oil is transported and regenerated and insulated. It is good also as a structure stored in an oil storage tank.
In addition, as a method of detoxifying the insulating oil, it is possible to use a metal sodium dispersion, but from the viewpoint of cost and reuse of the insulating oil, for example, the method described in Japanese Patent No. 3404402 may be used. preferable.

  Furthermore, even for matters that are not specifically exemplified in the method for regenerating an electrical device of the present embodiment, conventionally known technical matters are employed in the present invention as long as the effects of the present invention are not significantly impaired. It is possible.

DESCRIPTION OF SYMBOLS 1 Reproduction | regeneration apparatus 2 Pressure reduction mechanism 3 Pressure measurement mechanism 4 Detoxification mechanism 5 Cleaning mechanism 10 Suction pump 11 Oil absorption pipe 12 Sampling location 20 Vacuum pump 30 Reactor 31 Heater 40 Ammonia containing water storage tank 41 Sampling location 50 Cleaning tank 60 Oil water separation 70 Regenerated insulating oil transfer pump 80 Regenerated insulating oil storage tank 90 Virgin insulating oil storage tank 100 Cleaning agent supply pump 110 Heating mechanism L1 Branch piping section L2 Branch piping section L4 Ammonia-containing water transport piping section L5 Detoxified insulating oil transport piping section L6 Regenerative insulating oil transfer piping section L7 Cleaning agent supply piping section TR Transformer V1 Three-way valve V2 On-off valve V3 On-off valve V4 On-off valve V5 Three-way valve VC Vacuum gauge

Claims (9)

After performing an oil extraction step of extracting the insulating oil from the electrical equipment in which the insulating oil containing polychlorinated biphenyl is sealed in the housing, a new insulation having a polychlorinated biphenyl concentration of 0.5 ppm or less in the housing A method of regenerating an electrical device that renders the electrical device harmless and reusable by enclosing oil,
A method of regenerating an electrical device, comprising performing a diagnosis step of diagnosing the soundness of the casing by holding the interior of the electrical device in a reduced pressure state after the oil removal step.   The regeneration of an electric device according to claim 1, wherein the insulating oil containing polychlorinated biphenyl is used as a new insulating oil that is detoxified so that the concentration of polychlorinated biphenyl is 0.5 ppm or less and sealed in the electric device. Method.   The method for regenerating an electrical device according to claim 1 or 2, further comprising a cleaning step of cleaning the inside of the electrical device with an insulating oil having a polychlorinated biphenyl concentration of 0.5 ppm or less after the diagnosis step.   The method for regenerating an electrical device according to claim 3, further comprising a moisture measuring step of measuring moisture in the insulating oil after the inside of the electrical device is cleaned.   5. The pre-cleaning step of cleaning the inside of the electrical device with an insulating oil having a polychlorinated biphenyl content of 0.5 ppm or less after the oil removal step and before the diagnosis step. A method for regenerating an electrical device according to claim 1.   The method for regenerating an electrical device according to claim 5, wherein the preliminary cleaning step is performed on an electrical device in which an insulating oil containing the polychlorinated biphenyl at a concentration of 100 ppm or more is enclosed. After performing an oil extraction step of extracting the insulating oil from the electrical equipment in which the insulating oil containing polychlorinated biphenyl is sealed in the housing, a new insulation having a polychlorinated biphenyl concentration of 0.5 ppm or less in the housing A device for regenerating an electrical device for making the electrical device harmless and reusable by enclosing oil,
After the oil removal step, a pressure reducing mechanism for bringing the electrical device into the reduced pressure state and the reduced pressure state so that the soundness of the casing can be diagnosed by holding the inside of the electric device in the reduced pressure state. And a pressure measuring mechanism for measuring a pressure inside the electric device.   The apparatus for regenerating an electrical device according to claim 7, further comprising a cleaning mechanism for cleaning the interior of the electrical device after the oil removal step using an insulating oil having a polychlorinated biphenyl content of 0.5 ppm or less. .   The apparatus for regenerating an electrical device according to claim 8, wherein the cleaning mechanism includes means for heating the insulating oil used for cleaning.

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