JP2005204907A - Treatment system and method for rendering electric apparatus using electricity insulating oil containing polychlorinated biphenyl harmless - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To continuously use an electric apparatus using electricity insulating oil containing organic chlorine-based compound or to safely scrap the electric apparatus by eliminating the organic chlorine-based compound thereby cleaning the electricity insulating oil to be harmless state without disassembling the electric apparatus at a site where the electric apparatus is installed. <P>SOLUTION: A lead-out port of the electricity insulating oil nearly at the lower end of the electric apparatus is connected through an detachable pipe 4 to an apparatus for rendering the electricity insulating oil harmless with which dechlorination and hydrogenation is applied to the electricity insulating oil in the presence of a nickel-based catalyst in hydrogen gas atmosphere. The electricity insulating oil is poured from the electric apparatus to the pouring port of the apparatus for rendering the electricity insulating oil harmless to render the organic chlorine-base compound harmless and to be cleaned by using the catalyst reaction of the apparatus for rendering the electricity insulating oil harmless. Through a pipe 22 connecting the drain port of the apparatus for rendering the electricity insulating oil harmless detachably with an oil reservation tub 23 capable of housing nearly the whole amount of the cleaned electricity insulating oil, the cleaned electricity insulating oil is transferred to the oil reservation tub. Through a pipe 26 connecting the oil reservation tub and the lead-in port of the electric apparatus detachably, the cleaned electricity insulating oil is circulated back to the electric apparatus to make the electric apparatus itself harmless. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

The present invention relates to an electrical device such as a transformer or a circuit breaker, which is contained in an electrical insulating oil used as an insulating medium of an electrical device while the electrical device is assembled and installed in the field. A system for detoxifying electrical equipment using electrical insulation oil containing polychlorinated biphenyl using a dechlorination treatment equipment for electrical insulation oil containing polychlorinated biphenyl, which dechlorinates and hydrogenates chlorinated biphenyl. It relates to detoxification methods.
For the sake of convenience, the present invention will be described for the detoxification of an electrical insulating oil containing polychlorinated biphenyl (hereinafter referred to as PCB). Can be rendered harmless.

It has been a long time since the harmfulness of PCB, an organochlorine compound, was pointed out and production was discontinued.
However, PCB processing does not progress over a long period of time, and many electrical devices that use PCB or use electrical insulating oil mixed with PCB are still used in actual systems. In addition, electric appliances that have stopped using a large amount, use PCBs, or use electric insulating oil mixed with PCBs, and electric insulating oils mixed with PCB in a single state continue to be stored by their owners.
In recent years, technology for chemically detoxifying PCBs has been developed, and is based on the “Act on Waste Disposal and Cleaning (Act No. 137 of 1945)” (hereinafter referred to as the Waste Disposal Law). Public certification on PCB detoxification (hereinafter referred to as public certification) has also been institutionalized, and some holders use PCBs or use PCBs mixed with electrical equipment or PCBs containing electrical insulation oil. Processing has begun.

  By the way, most PCBs that require processing are used as insulating media in power receiving and transforming devices such as transformers and circuit breakers. Insulating media include “when PCB itself or PCB is used as a main component” (hereinafter referred to as high-concentration PCB) and “electric insulating oil mixed with a very small amount of PCB for some reason” (hereinafter referred to as low-density PCB). Density PCB). According to a survey by the Japan Electrical Manufacturers' Association, the PCB concentration of low-concentration PCB (hereinafter, the PCB concentration may be expressed in ppm for convenience) is almost 10 ppm or less and at most about 100 ppm. . Since the highest concentration of reported cases sampled in this survey was 2,110 ppm, it is appropriate to assume that the maximum concentration is about 10,000 ppm (= 10,000 mg / kg = (1%)). Let's go. The present invention relates to detoxification of low-concentration PCBs of more than 0.5 mg / kg to 10,000 mg / kg or less.

  So far, low-concentration PCBs have been considered to have been mixed with PCB when regenerating electrical insulation oil, and it has been found that regenerated electrical insulation oil is mainly used in pole transformers. Yes. However, many cases have been reported where PCBs are detected from electrical equipment using new oil that has been considered to be near or not containing PCB, and PCB contamination has spread to all electrical equipment that uses electrical insulating oil. Turned out to be. There are many occasions where PCBs can be mixed, such as the production process of electrical insulating oil, transportation, storage, various work processes, handling equipment, maintenance, etc., and any of these or a combination of factors may cause mixed contamination. It is thought that.

Now, all of the low-concentration PCB detoxification technologies that have been published so far only render the insulating oil containing PCB harmless, and the electrical insulation oil and the main body of the electrical equipment that uses the electrical insulating oil. Not intended for reuse. In other words, even if it is not premised on aggressive disposal, it is premised on disposal including recycling or disposal including recycling as a result. Recycling here refers to diverting the harmless electrical insulating oil to fuel or returning the metal member of the electrical equipment to the original metal.

  As described above, low-concentration PCBs have been considered to be detoxified and discarded even though a very small amount of PCB is contained in the electrical insulating oil. It can be said that it has been. “Special Measures Act on Promotion of Proper Treatment of Polychlorinated Biphenyl Waste (Act No. 65 of 2001)”, which is a law for the proper disposal of PCBs, and the above-mentioned origin of this law The “Waste Disposal” and the like are all named after the word “Disposal”.

  Electrical equipment mixed with low-concentration PCBs, especially large electrical equipment, is not only expensive when renewing electrical equipment, but also requires a large amount of cost for detoxification treatment, and from the electrical system. It also takes a lot of money to separate and move from the installation site. Moreover, it is not only a problem of cost, but it is sometimes difficult to carry out or carry an electric device having a dense electric power demand, particularly installed in the city center or underground in the city center. In other words, since the electrical equipment contains PCB, there are parts that cannot be divided or disassembled. On the other hand, in order to carry it out, it is necessary to divide or disassemble the electric equipment. There is a possibility of falling into self-confidence due to the contradicting conditions.

  Furthermore, even when the electric device can be carried out, there is a more essential problem that it is difficult to make the electric device harmless. In other words, regarding the detoxification of low-concentration PCBs, many chemical treatment methods have passed and been certified by the public examination based on the above-mentioned waste cleaning method, but the transformer is composed of wires coated with insulating paper. A low-concentration PCB penetrates and penetrates deep inside the coil. In addition, a large amount of paper-like laminated materials and wood materials such as press boards are used, and the low-concentration PCB is also infiltrated into the materials. In addition, the members of large electric devices have various shapes and sizes, including long and heavy products. That is, since PCB which is a harmful substance is contained, it is large, heavy, and has various shapes, it is not easy to handle for detoxification.

At least at the time of patent application of the present invention, such a large electric device itself has not been detoxified, and there is no information to realize such a process.
That is, a large electric device using a low-concentration PCB cannot be rendered harmless by the conventional technology. As a result, it is impossible to renew the electrical equipment, so it is not possible to take measures such as renewing or increasing the capacity of the electrical equipment in response to the decline in reliability. There is a great deal of concern.

The present invention renders the low-concentration PCB contained in the electrical insulating oil harmless against such a situation and renders the electrical equipment itself harmless by allowing it to be used as it is.
Although the present invention is particularly effective when applied to a large electric device, as described below, the electric device can be used continuously with the electric device assembled. The effect of detoxifying the PCB can be expected to be sufficiently effective even when applied to a small electric device.

The system for detoxifying an electrical device itself contaminated with polychlorinated biphenyl according to claim 1 comprises an electrical device using an electrical insulating oil containing polychlorinated biphenyl of more than 0.5 mg / kg to 10000 mg / kg, hydrogen A detoxifying device for electrical insulating oil that dechlorinates, hydrogenates and detoxifies polychlorinated biphenyl under a nickel-based catalyst with a framework of zeolite / nickel or nickel / molybdenum, nickel / platinum, etc. in a gas atmosphere The process of passing between the first pipe detachably connecting the inlet of the detoxifying treatment apparatus for the electrical insulating oil from the substantially upper or lower outlet of the electrical equipment and the catalyst in the hydrogen gas atmosphere Dechlorination of the catalyst generated in the process, detoxification treatment of polychlorinated biphenyl using a hydrogenation reaction, and an oil storage tank for storing the refined electrical insulating oil, A second pipe that detachably connects an oil storage tank that stores the refined electrical insulating oil from the discharge port of the detoxification treatment device, and the outlet port of the electrical device from the oil storage tank that houses the refined electrical insulation oil; A detoxification treatment system for electrical insulating oil containing polychlorinated biphenyl constituted by a third pipe that removably connects an introduction port at a substantially opposite end, from the electrical device to the injection port of the detoxification treatment apparatus Injecting electrical insulating oil containing the polychlorinated biphenyl, dechlorination generated in the process of passing between the catalyst in a hydrogen gas atmosphere, detoxifying the polychlorinated biphenyl using a hydrogenation reaction, The refined electrical insulating oil is transferred to the oil storage tank from the discharge port opposite to the injection port of the detoxification treatment device, and the introduction port at the opposite end to the oil storage tank and the outlet port of the electrical equipment is detachably connected. By the third pipe , Refined electrical insulation oil [electric equipment → outlet of electrical equipment → first piping → inlet of detoxification treatment equipment → catalyst under hydrogen gas atmosphere → discharge port of detoxification treatment equipment → second piping → oil storage A system that detoxifies the electrical equipment itself using electrical insulating oil containing polychlorinated biphenyl by circulating through the tank → third piping → electrical equipment inlet → electrical equipment].
The system for detoxifying electrical equipment itself contaminated with polychlorinated biphenyl according to claim 2 is the second pipe for transferring purified electrical insulating oil from the discharge port of the detoxification processing device to the oil storage tank in the invention of claim 1 Then, a third pipe to be circulated again to the inlet of the detoxification treatment apparatus is branched, a stop valve is provided in each of the second pipe and the third pipe, and the discharge port is opened and closed by opening and closing the stop valve. It was configured so that the electrical insulation oil in the process of refining can be selected and distributed to the detoxification processing device from the third pipe to the detoxification processing apparatus, or the electrical insulation oil that has been refined to the oil storage tank by the second pipe. A system for detoxifying electrical equipment itself using electrical insulating oil containing polychlorinated biphenyl according to claim 1.
The system for detoxifying the electrical equipment itself contaminated with polychlorinated biphenyl according to claim 3 comprises an insulative treatment device for electrical insulating oil, which is moved to the installation location of the electrical equipment and contains polychlorinated biphenyl. The electrical insulation oil is used to detoxify the electrical insulation oil by connecting to the oil storage tank and the oil storage tank at the site, and after the detoxification process, the detoxification treatment device is separated from the oil storage tank and the electrical equipment, It is configured to be able to move to a place different from the electrical equipment, and the electrical equipment itself using the electrical insulating oil containing polychlorinated biphenyl according to claim 1 and claim 2 is rendered harmless. system.
The system for detoxifying an electrical device itself contaminated with polychlorinated biphenyl according to claim 4 uses a tank lorry vehicle as an oil storage tank. A system that renders electrical equipment harmless using electrical insulating oil containing biphenyl chloride.
The method of detoxifying an electrical device itself contaminated with polychlorinated biphenyl according to claim 5 is an electrical device using an electrical insulating oil containing polychlorinated biphenyl of more than 0.5 mg / kg to 10000 mg / kg, The electrical insulation oil detoxification treatment equipment that dechlorinates, hydrogenates and detoxifies biphenyl chloride is connected, and the electrical insulation oil is injected from the electrical equipment into the detoxification treatment equipment inlet. Store the refined electrical insulating oil, which has been made harmless in the process of circulating in the treatment equipment, from the discharge port of the detoxification treatment equipment to the oil storage tank, and further collect the residual amount of electrical insulation oil dripped into the electrical equipment, A method of detoxifying the electrical device itself by recirculating the refined electrical insulating oil injected into the inlet of the detoxification processing apparatus and stored in the oil storage tank to the electrical device.

The present invention is based on the idea of reversal, which utilizes the high stability that PCBs are not easily altered and do not chemically react with other substances in normal use environments.
That is, the problem with electrical equipment using electrical insulating oil mixed with PCB is that the electrical insulating oil contains PCB, and PCB adheres to the electrical equipment body or soaks into components. However, this does not mean that the main body of electrical equipment except for low-concentration PCB has been changed into harmful ones. Therefore, if the PCB contained in the low-concentration PCB is removed or rendered harmless, the electrical equipment containing the electrical insulating oil becomes harmless. This is an important focus point of the present invention.

  That is, the important point of the present invention is that the conventional low-concentration PCB and the main body of the electrical equipment using the low-concentration PCB are handled separately, and “PCB is made harmless and discarded”, “ From the idea that the main body of the electrical equipment contaminated by the PCB is to be disposed of after detoxifying the adhered and soaked PCB, it has been said that the electrical equipment itself is made harmless in the assembled state. This is to change the processing mechanism in a direction that was not even envisaged in the laws on processing. After the electrical device itself has been rendered harmless, whether to continue using the electrical device or to discard the electrical device and replace it with a new electrical device may be determined as necessary.

There are various methods for detoxifying PCBs that have obtained the above public certification, but the present invention can be used as electrical insulation oil after removing PCB from electrical insulation oil containing PCB. This method can be applied only to a detoxification method.

In order to promote the detoxification of PCBs, one company that is a patent applicant of the present invention is an economical, non-polluting zeolite / nickel, nickel / molybdenum, nickel / platinum or other nickel skeleton. A patent application was filed for a method of detoxifying PCB under a system catalyst (hereinafter referred to as catalyst), and it was registered as Patent Document 1. In addition, one of the inventors of the present invention applied for Patent Document 2 in 2000 with respect to a device for purifying electrical insulating oil to which the principle of the invention of Patent Document 1 was applied. The invention of the patent document 1 and the detoxification treatment apparatus of the patent document 2 to which the principle is applied have been found to be practical after examination by the [Refractory Organic Compound Processing Technology Examination / Evaluation Committee]. As the catalytic hydrogen reduction method in the dechlorination method, which is a detoxification treatment method, the above-mentioned public certification was obtained in May 2001. Furthermore, one of the inventors mentioned above filed Patent Document 3 in 2003 as an invention that dramatically increases the detoxification processing ability of the invention of Patent Document 2.
Patent No. 1982066 (Japanese Patent Publication No. 7-10995) JP 2001-279290 A Japanese Patent Application No. 2003-351420

In the present invention, attention is focused on Patent Document 2 and Patent Document 3.
That is, Patent Document 2 is a PCB to which the PCB detoxification principle of the invention of Patent Document 1 is applied.
Patent Document 3 is an invention in which the purification ability of PCB of the invention of Patent Document 2 is further improved. In any case, the biphenyl compound produced when detoxifying PCB is used as it is as insulating oil. One of the features is that it can be used as a part of

  The catalytic hydrogen reduction method which has obtained the above public certification is a practical form of the PCB detoxification treatment principle of the invention of Patent Document 1 and the invention of Patent Document 2 which is a PCB refining device to which the principle is applied. This is a realized PCB detoxification technology. The mechanism of detoxification is very simple. Chlorine Cl, which is the origin of PCB toxicity, is replaced with hydrogen H to convert it into a harmless biphenyl compound, and the separated chlorine is removed in the form of saline. Therefore, the biphenyl compound in which PCB is hydrogenated is mixed with the electrical insulating oil and becomes a part of the electrical insulating oil.

  PCB has the chemical structure shown in FIG. 1 and has 1 to 10 chlorine atoms attached to carbon of a biphenyl nucleus in which two hexagonal carbon rings are connected. (FIG. 1 shows the case of five chlorines) Carbon has a tetravalent element, that is, four arms, each having a property of being connected to another substance. In the case of PCB, each carbon arranged in a hexagonal shape is connected to adjacent carbon by one arm and the other one by one arm, and one of the remaining arms is the outer periphery of the hexagonal carbon ring. It is connected to chlorine or hydrogen. As mentioned above, even if the number of chlorine is 1 to 10, it is a substance called PCB, and there are various isotopes depending on the number of chlorine and the position where it is attached. It is said that. As shown in FIG. 1, hydrogen is attached to the position where chlorine is not attached.

  The catalytic hydrogen reduction method is a technique for replacing chlorine with hydrogen, and replaces chlorine with hydrogen regardless of the number of chlorine in the PCB and the position where the chlorine is attached. The structure in which PCB chlorine is replaced with hydrogen is biphenyl with one hydrogen on carbon, bicyclohexyl with two, phenyl with one on one of the hexagonal carbocycles and two on the other Although there are three forms of cyclohexane, they are collectively called biphenyl compounds, each of which is harmless and is a highly stable substance that is also used for a heating medium. The structures of the three types of biphenyl compounds are shown in FIG. FIG. 1 and FIG. 2 are diagrams showing the state in which chlorine or hydrogen is attached to the carbocyclic ring in an easy-to-understand manner, and are original drawings of the present inventor that are slightly different from ordinary chemical formulas.

  As can be seen from a comparison of the chemical structures in FIGS. 1 and 2, the biphenyl compound has a structure in which the chlorine around the two carbocycles of the PCB is replaced with hydrogen, and the entire structure becomes hydrogen. Can easily be expected to be highly similar. Moreover, most of the low-concentration PCBs originally have a PCB concentration of several ppm, at most about 100 ppm, that is, the electrical insulating oil contains only about 0.01% or less, so the PCB did not adversely affect the insulation performance. Thus, even if it is mixed in the electrical insulating oil as it is, it does not matter that the insulating performance is not affected. Table 1 shows the results of experiments conducted when the catalytic hydrogen reduction method was officially certified as a PCB detoxification treatment technology, and all items defined the characteristics of electrical insulation oil. JIS C 2320 “Electric insulation oil” The specified value is satisfied. Table 1 is published in [<PCB Contaminated Oil Treatment Technology> “Catalyst Hydrogen Reduction Method” Demonstration Test Result Report], which is a document of the results of the examination by the aforementioned [Refractory Organic Compound Treatment Technology Review and Evaluation Committee]. The table is reprinted.

(Table 1) Properties of refined electrical insulating oil made by detoxifying low-concentration PCB

That is, the catalytic hydrogen reduction method can be used as an electrical insulating oil even after detoxification treatment, and can be refluxed to an electrical device.

According to the present invention, an electrical device using a low-concentration PCB can be rendered harmless while the electrical device is assembled at a site where the electrical device is installed.
Moreover, since the electrical device is converted into a harmless electrical device, it can be used continuously.
A method of directly connecting the electrical equipment and the detoxification treatment apparatus and decirculating the low-concentration PCB to the electrical equipment to circulate is also conceivable, but an oil storage tank is provided after the discharge port of the detoxification treatment equipment. Then, the electrical insulating oil of the electrical device can be extracted once, so that the dripping portion of the electrical insulating oil trapped inside the electrical device can be collected and detoxified, and remains in the electrical device. PCB can be reduced. That is, it is possible to return the detoxified electrical insulating oil from the oil storage tank and reduce the PCB concentration when the PCB reaches a dissolution equilibrium.
In addition, when an oil storage tank is not provided after the detoxification treatment device and the electrical equipment is continuously used after the detoxification treatment, the electrical insulation oil heated up during the detoxification purification of the electrical insulation oil If the temperature is not lowered, it cannot be put back into the electric device. However, when an oil storage tank is provided, the temperature can be lowered by storing in the oil storage tank, so that the cooler is not necessary.
Furthermore, using an oil storage tank, an additive for improving the characteristics of the electrical insulating oil can be introduced to adjust the components.

In summary, it can be said that the present invention provides the following effects.
1. When using an electric device continuously 1) Since an electric device can be used as it is, it is not necessary to manufacture a new electric device.
2) The PCB can be detoxified much more economically than the conventional method of separately detoxifying the electrical insulating oil and the electrical device main body.
3) There is no need to disconnect the electrical equipment from the system, and there is no need to replace it with a replacement electrical equipment, so the cost and time required for the work are not required.
4) Costs and time for carrying out electrical equipment from the site, and costs and time for installing and installing alternative electrical equipment do not occur.
2. Disposal of electrical equipment 1) The PCB can be detoxified much more economically than the conventional method of separately detoxifying the electrical insulating oil and the electrical equipment body.
2) Since it will be converted into harmless electrical equipment, it will be possible to extract the electrical insulating oil from the electrical equipment locally, and it will be possible to remove the electrical equipment locally after dividing it into the required size and shape. .
3) Since it becomes a harmless electrical device, it is possible to safely disassemble, carry out and transport the electrical device.
In any case, the economic and temporal effects are enormous and can be expected to be immeasurable.
However, the greatest effect is that it can contribute to the stable supply of electric power as a basic social infrastructure accompanying the detoxification of large electric devices.

Hereinafter, the specific contents of the present invention will be described in detail with reference to examples.
FIG. 3 shows that the transformer 2 itself is rendered harmless by the refining system of the electrical insulating oil configured by combining the refining device 1 of the low-concentration PCB, the transformer 2 and the oil storage tank 23 to which the invention of Patent Document 3 is applied. It is a figure explaining the specific structure of this invention for demonstrating this. The refinement | purification apparatus 1 means the whole refinement | purification apparatus of the low concentration PCB6a except the transformer 2 and the oil storage tank 23. FIG.
Note that the transformer 2 represents electric equipment in general, and any electric equipment may be used as long as it is an electric equipment using the low-concentration PCB 6a.

  The low concentration PCB 6 a is led out from the transformer 2 by a pump 5 through a first pipe 4 that is connected to the lead-out port 3 at the substantially lower end of the transformer 2 and is detachable from the transformer 2. An inlet 8 for caustic soda 7 is disposed in the first pipe 4, and the low-concentration PCB 6 a and the caustic soda 7 are agitated and mixed in the process of flowing through the first pipe 4 or by the pump 5. The mixing of the low-concentration PCB 6a and the caustic soda 7 may be performed by arranging a stirrer (not shown) in the middle of the first pipe 4.

  Next, the low-concentration PCB 6a is heated to 150 to 250 ° C. by the heater 9 so that the chemical reaction for separating and hydrogenating chlorine progresses quickly, and then provided at the upper end of the container 11 of the purification apparatus main body 10. Low concentration PCB 6a is injected from the inlet 12.

The purification of the low-concentration PCB 6a progresses faster when the pressure is higher, but the purification reaction proceeds even at atmospheric pressure. In the invention of Patent Document 1 that is the basis of the present invention, the results of a purification experiment with a hydrogen gas pressure of 80 kgf / cm ² are explained. However, the experiment was performed using the apparatus of the invention shown in Patent Document 2. As a result, it has been found that sufficient practical performance is exhibited even at atmospheric pressure, and the result is applied to the invention of Patent Document 2. The official certification is that the decontamination treatment is performed on a low-concentration PCB having a concentration of 1% (10,000 mg / kg) or less at a temperature = 150 to 250 ° C. and a pressure = atmospheric pressure to 0.3 MPa. It has become. The detoxification process conditions of the present invention are within the scope of public certification.
In the verification test for obtaining public certification, 100 liters of low-concentration PCB with a temperature of 250 ° C and a PCB content of 100 ppm was injected in 3 hours in a refiner for electrical insulating oil containing 35 kgf of catalyst (average particle size 2 mm). As a result of the treatment, the dechlorination reaction is almost completely performed at any pressure of atmospheric pressure (1 kgf / cm ² ), 5 kgf / cm ² , and 50 kgf / cm ² , As a result of analyzing the residual PCB and the amount of coplanar PCB, which is said to be particularly toxic, by gas chromatography mass spectrometry / selected ion detection (GC-MS / SIM method), all were below the lower limit of detection (ND). Details of the results are described in Patent Document 2 and will be omitted.

Now, the catalyst 13 is enclosed in the container 11 in advance, and the low-concentration PCB 6a injected into the purifier main body 10 is stored in the container 11 in the lower part of the purifier main body 10 while being in contact with the catalyst 13. It moves toward the part 14. At this time, hydrogen gas 16 is sent from the hydrogen gas supply port 15 of the container 11, and chlorine is desorbed from the PCB contained in the low-concentration PCB 6 a on the surface of the catalyst 13 and changed to hydrogen chloride. The produced hydrogen chloride is immediately neutralized by the caustic soda 7 mixed in the low-concentration PCB 6a, and changes into salt (NaCl) + water (H ₂ O) = saline.

A PCB measurement device 17 is installed in the storage unit 14 so that the progress of detoxification of the PCB can be checked.

The discharge port 18 of the storage unit 14 is connected to the oil storage tank 23 by a detachable second pipe 22 in which a salt separation filter 19, an oil / water separator 20, and a pump 21 are arranged. When the progress of detoxification of the low-concentration PCB 6a is measured and the detoxification is achieved, the refined electrical insulating oil 6b detoxified from the low-concentration PCB is transferred from the second pipe 22 to the oil storage tank 23. The
Chlorine separated from PCB, excess caustic soda 7, and hydrogen gas 16 are both harmful to the transformer because salt and water produced by chemical reaction are both harmful. The refined electrical insulating oil 6b must be removed before returning to the transformer 2.

  The processing capacity of the low-concentration PCB 6a of the refining device 1 does not need to have the capability of detoxifying all the low-concentration PCB 6a used in the transformer 2 at once. The low-concentration PCB 6a is made harmless by an amount suitable for the refining capacity of the refining device 1, and is sequentially sent to the oil storage tank 23 as a refined electrical insulating oil 6b.

  The oil storage tank 23 has a capacity for storing almost the entire amount of the low concentration PCB 6a of the transformer 2, and the oil is stored until "almost all" of the low concentration PCB of the transformer 2 is rendered harmless. However, at this stage, the PCB is rendered harmless by “almost all” of the low-concentration PCB 6 used in the transformer 2 and not by “total amount”. That is, as described above, the low-concentration PCB 6a used in the transformer 2 is attached to the container of the transformer 2 or trapped by insulating paper or the like, and is discharged from the transformer 2 by the pump 5. There is a limit to the low-density PCB 6a that can be produced.

The refined electrical insulating oil 6b extracted from the transformer 2 and rendered harmless is transformed from an inlet 27 that is substantially opposite to the outlet 3 of the transformer 2 through a third pipe 26 that is detachable from the oil storage tank 23. To reflux.
When decontaminating the low-concentration PCB 6a, it was once heated to 150 to 250 ° C., but the allowable temperature of the transformer is designed to be about 100 ° C., so the purified electrical insulating oil 6b is returned at this temperature. I can't help. However, since it cools while being put into or stored in the oil storage tank 23, the temperature of the oil needs to be checked before returning to the transformer 2, but the refined electrical insulating oil 6 b is temporarily placed in the oil storage tank 23. Is convenient.

In the middle of the second pipe 22, a detachable fourth pipe 24 communicating with the inlet 12 of the purification apparatus main body 10 is branched and disposed via the heater 9. The second pipe 22 is provided with a stop valve 25a and a stop valve 25b, respectively. If the measurement device 17 determines that the low-concentration PCB 6a is not detoxified because the PCB concentration of the low-concentration PCB 6a is high, the low-concentration PCB 6a that is in the process of purification is removed from the middle of the second pipe 22. The detoxification process can be continued by circulating through the fourth pipe 24 to the purification apparatus main body 10 via the heater 9.
It is described in detail in Patent Document 3 that the purifying apparatus 1 has this reflux system, that is, the low concentration PCB 6a can be circulated to achieve a desired detoxification level.

Whether the oil is transferred from the second pipe 22 to the oil storage tank 23 or circulated to the purifier main body 10 via the heater 9 is controlled by operating the stop valves 25a and 25b. That is, while the detoxification process is continued, the stop valve 25a is opened, the stop valve 25b is closed, and the low-concentration PCB 6a that is being detoxified and is discharged from the purifier main body 10 is removed from the second pipe 22 through the second pipe 22. 4 is circulated through the purifier main body 10 through the pipe 24 of the required number of times. When the PCB detoxification reaction is completed, the stop valve 25 a is closed, the stop valve 25 b is opened, and the purified electrical insulating oil 6 b is led out from the second pipe 22 to the oil storage tank 23.
Note that the fourth pipe may not be branched from the second pipe, but may be provided in the storage unit 14 together with the second pipe.

Moreover, although the case where the measuring device 17 of PCB was installed in the storage part 14 was demonstrated, depending on the cost of the measuring device 17 and the time which analysis requires, the measuring device 17 is not added to the refiner | purifier main body 10, For example, it prepares separately. Analyzing apparatuses that have been used or existing analyzing apparatuses may be used.
Further, depending on the size and manufacturing cost of the purification apparatus main body 10, the storage unit 14 may be separated from the purification apparatus main body 10 and installed in the middle of the second pipe 22.

  The nitrogen gas 28 is used for security to prevent air from entering the purifier main body 10 and reacting with the hydrogen gas 16.

  This electrical insulation oil refining system handles PCBs that are said to be harmful and performs chemical treatment at the place where the transformer 2 is installed, so it should be configured as a closed system including the transformer 2. is required.

  As described above, the present invention is mainly aimed at detoxifying the electrical equipment itself such as a large transformer, but even if it is a large transformer, the capacity is relatively small. There are large electrical devices that exceed 300 MVA from 10 MVA class products, and there is a product group that has a difference of several tens of times in the amount of electrical insulating oil used. Depending on the size of the target transformer 2 to be detoxified, it may be appropriate to give the refining apparatus 1 an appropriate refining capacity, but depending on the refining apparatus 1 having a relatively small refining capacity, various capacities can be obtained. Application to the transformer 2 is important from the viewpoint of economic efficiency, and the refining capacity of the refining apparatus 1 is considered in consideration of the capacity of the transformer 2 to which the present invention is applied, the quantity to be detoxified, the processing period, and the like. It is necessary to decide.

  The important point of the present invention is that after the low-concentration PCB 6a existing in the form of a single liquid is extracted from the transformer 2, the low-concentration PCB 6a that is naturally dropped and collected in the transformer 2 is further extracted from the transformer 2, and insulating paper is used. PCBs contained in the low-concentration PCB 6a captured in the transformer 2 and remaining in the transformer 2 are exuded and dissolved in the refined electrical insulating oil 6b in which the decontamination of the low-concentration PCB has been made harmless, and the electric insulation is sufficiently reduced In other words, a technique is adopted in which the so-called graduation standard regarding detoxification is achieved by balancing with the PCB concentration in the oil 6b. Explain the optimal use of the law of partitioning that causes spontaneous dripping and dissolution equilibrium.

First, the distribution law and the PCB concentration balance will be described.
When insulating paper or the like soaked in electrical insulating oil containing PCB with high concentration is immersed in electrical insulating oil containing PCB with low concentration or PCB with low concentration, electrical insulation with high PCB concentration captured by insulating paper etc. PCBs ooze out of the oil into electrical insulating oil that contains no PCBs or low concentrations of PCBs. This is called the law of distribution, and is a universal physical phenomenon that occurs outside of PCB. When the PCB concentration in the electrical insulating oil captured by the insulating paper or the like and the PCB concentration in the electrical insulating oil existing in a single liquid state reach an equilibrium (equal), the bleeding of the PCB stops.
Fig. 4 shows that the electrical insulation oil is extracted from a small transformer mixed with low-concentration PCB of about 20 ppm and replaced with electrical insulation oil that is a new oil that does not contain PCB. The experimental result which measured the exudation and the dissolution condition is shown. The PCB captured by the insulating paper or the like starts to dissolve in the new oil immediately after the electric insulating oil is replaced, and the leaching rate decreases as the PCB concentration in the new oil increases. In this experiment, the PCB concentration in the fresh oil reached saturation in about 25 days. It was confirmed that the PCB concentration in the new oil at this time matched the concentration at equilibrium calculated from the total amount of PCB captured in the insulating paper or the like and remaining in the transformer. PCB leaching / dissolution rate from insulating paper or the like into the electrical insulating oil, that is, the time until the PCB concentration in the electrical insulating oil and the electrical insulating oil captured by the insulating paper equilibrates is the PCB concentration or insulation Although it depends on the type and amount of insulating oil-permeable material such as paper, as described above, even a small transformer requires about one month. Large electric devices with a complicated structure and a large amount of insulating paper or the like used are considered to require a longer period of time. When actually processing the low-concentration PCB 6a, it is necessary to make a schedule according to the actual situation.

Next, natural dripping will be described.
Results of experiments on the amount of adhesion due to gravity dripping and the reduction of the amount of trapped electrical insulating oil attached to the container wall of the transformer and the insulating oil permeable material such as insulating paper Are shown in FIG. 5 and FIG.

  Fig. 5 shows the results of an experiment on the reduction of the electrical insulating oil adhering to the wall of the container when the container was turned upside down after the electrical insulating oil was extracted from the container of the small transformer containing the electrical insulating oil. is there. The amount of decrease in the adhered electrical insulating oil was converted from the change in the weight of the container. According to FIG. 5, only 0.1% of the used electric insulating oil remains on the container wall surface in about 1 minute. That is, most of the electrical insulating oil is dripped in a short time. Therefore, when actually detoxifying the PCB, the low-concentration PCB 6a only attached to the wall surface of the container of the transformer 2 while the low-concentration PCB 6a is transferred from the transformer 2 to the refining device 1 Since it drops to the bottom of the transformer 2 and can be recovered, there is no need to pay particular attention.

FIG. 6 is a result of an experiment on a decrease state of the captured electric insulating oil when the electric insulating oil captured by the insulating paper or the like is naturally dropped while the content of the transformer is lifted. Also in this case, the amount of electrical insulating oil captured was converted from the change in weight of the transformer contents. In the case of the contents of the transformer, immediately after the contents are lifted, the electrical insulating oil adhering to or captured by the contents starts to decrease rapidly due to natural dripping due to gravity. Within 30 minutes, about 1% of the electrical insulating oil used in the transformer drops from the transformer, but the amount of natural dripping decreases in a quadratic curve. It takes time. As described above, the amount of low-concentration PCB that can be recovered by natural dripping is limited, but if it is attempted to recover as much low-concentration PCB as possible by natural dripping, it must be considered that a considerable amount of time is required.
However, this is easy to match with the processing capacity of the refining apparatus 1 applied to the present invention, which is also an advantageous aspect. That is, as described above, the refining device 1 does not need to have a processing capacity for refining the entire amount of the low-concentration PCB 6a used in the transformer 2 at once, and the decontamination treatment is performed by dividing the low-concentration PCB 6a several times. I do. In addition, depending on the PCB concentration, the purification device 1 is repeatedly circulated to perform the detoxification process, which requires a considerable amount of work. As a result, the detoxification process is advanced in parallel work while stepping on the natural dripping process, so that it is not necessary to set a work time for promoting the natural dripping.

Now, let us consider the case where the results up to here are applied to a real device.
The so-called graduation standard for PCB detoxification is 0.5 mg / kg (≈0.5 ppm).
1) Setting conditions for consideration ・ The total amount of electrical insulating oil used in the transformer is 20 kg.
・ After 12 hours of natural dripping treatment, the amount of electrical insulating oil still trapped in the transformer is 6% as shown in FIG.
-Refine the PCB concentration of the electrical insulating oil alone to 0.1 ppm by detoxification treatment.
2) PCB concentration of transformer that can satisfy graduation criteria when it reaches dissolution and equilibrium If PCB concentration before detoxification treatment is χppm (χmg / kg),
・ The amount of PCB trapped in the transformer 20 × 0.06 × χ (mg)
-PCB content in detoxified electrical insulation oil 20 x (1-0.06) x 0.1 (mg)
・ The amount of PCB when detoxified electrical insulating oil is returned to the transformer is this sum.
20 × 0.06 × χ + 20 × (1−0.06) × 0.1 (mg)
・ On the other hand, detoxified electrical insulating oil is returned to the transformer, and the PCB concentration after equilibrium is the graduation standard concentration (0.5 ppm) 20 × 0.5 = 10 (mg)
Therefore, the initial PCB concentration of the electrical insulating oil of the transformer that can meet the graduation criteria after equilibrium is 20 × 0.06 × χ + 20 × (1−0.06) × 0.1 = 20 × 0.5
χ = {0.5− (1−0.06) × 0.1} /0.06≈6.8 (mg / kg)
That is, if the initial PCB concentration of the electrical insulating oil is about 6.8 ppm or less, it is possible to satisfy the graduation criteria in one process.
Since the PCB concentration of large transformers is considered to be almost 5 ppm or less, the purpose of detoxification can be achieved under the above conditions.

However, it is not sufficient for processing with a margin, or for detoxifying the higher concentration PCB mixed oil.
Therefore, to detoxify a transformer with such conditions,
1) Repeat the same steps as above.
2) Reduce the purity of the electrical insulating oil to be detoxified below 0.1 ppm.
3) Increase the recovery rate of low-concentration PCB.
As the method,
a) Make the natural dripping time longer.
b) The internal pressure of the transformer 2 is reduced by a so-called evacuation operation to increase the fluidity of the low-concentration PCB and increase the dripping amount.
A large transformer is an electrical device that is originally lubricated so that it does not come into contact with air after evacuation, and is strong enough to withstand evacuation.
There are methods.
Further, as seen in FIG. 4, the larger the PCB concentration difference, the faster PCB bleeds into the electrical insulating oil. Therefore, if the refined electrical insulating oil 6b, whose PCB concentration has been reduced by detoxification treatment, is applied to the transformer contents so as to pour down from the upper part of the transformer 2, it will soak into the insulating paper and the like again, and the PCB will naturally become darker. Dripping. If this is recovered and rendered harmless, the total amount of PCB captured by insulating paper or the like can be quickly reduced. However, since the refined electrical insulating oil 6b poured down is contaminated by the PCB and becomes a low-concentration PCB 6a, it is necessary to collect it again and perform a PCB detoxification process. When spraying the refined electrical insulating oil 6b, it is important to determine the required amount in accordance with the actual situation in consideration of the structure of the transformer 2, the PCB concentration, and the like.
By applying the method described above, it is possible to easily detoxify electrical equipment that contains even higher concentrations of PCB. However, which method is used, and some methods can be used in combination. It is better to choose according to the actual situation.

The PCB detoxification treatment can reach the so-called graduation standard and eliminate the need for specific hazardous industrial waste if the PCB concentration in the electrical insulating oil is 0.5 mg / kg (≈0.5 ppm) or less. It is defined by the Waste Disposal Law. By the method described above, the PCB remaining on the insulating paper or the like in the transformer 2 is extracted into the refined electrical insulating oil 6b that has been made harmless, and the PCB and the refined electricity captured by the insulating paper or the like. If the PCB concentration of both PCBs in the insulating oil 6b reaches the equilibrium state, the low concentration PCB 6a becomes harmless purified electrical insulating oil 6b and the transformer 2 itself is harmless. It becomes equipment.
It takes a long time for the PCB to be extracted from the low-concentration PCB 6a soaked in insulating paper, etc., and to reach equilibrium with the PCB concentration of the refined electrical insulating oil 6b, but the transformer 2 is used continuously. In that case, there is no need to rush to achieve PCB detoxification.

In addition, it is economically desirable that the refining apparatus 1 is separated from the transformer 2 after the decontamination process of the low-concentration PCB 6a is completed so that the next transformer 2 can be detoxified. For that purpose, the refiner | purifier 1 is good to comprise with a vehicle-mounted type or a portable type. In particular, if it is an on-vehicle type, it can be moved quickly, and it meets the social demand for promptly detoxifying the PCB.
As another embodiment, FIG. 7 shows a harmless treatment system for the transformer 2 in which the in-vehicle refining device 1 is applied to a car 29.

  In the above description, the oil storage tank 23 is described as an independent container. However, the oil storage tank 23 is preferably portable, and a commercial vehicle such as a tank truck may be used as it is. Although there is a restriction on the amount of low-concentration PCB 6a, it can be dealt with by connecting a plurality of vehicles and is suitable for reuse. Further, when the refining device 1 is configured as an on-vehicle type, it becomes easy to operate in synchronization with the tank truck 30 serving as the oil storage tank 23, and the utilization efficiency is further increased, and the concentration is reduced quickly and economically. It is possible to detoxify the PCB 6a. As another embodiment, FIG. 8 shows a case where a tank truck 30 is applied to the oil storage tank 23.

It is a figure which shows an example of the chemical structure of PCB. It is a figure which shows the chemical structure of the biphenyl compound which hydrogenated and detoxified PCB. It is a figure which shows one Example of the detoxification processing system of the electric equipment using the electric insulation oil containing the polychlorinated biphenyl of this invention. It is a figure which shows the experimental result which measured the exudation in the electric insulation oil of PCB, and the dissolution condition. It is a figure which shows the experimental result in which the electric insulation oil adhering to the container of a transformer reduces by the natural dripping by gravity. It is a figure which shows the experimental result in which the electric insulation oil capture | acquired by the insulating paper etc. of the content of the transformer 2 reduces by the natural dripping by gravity. It is a figure which shows the other Example of the detoxification processing system of the electric equipment using the electric insulation oil containing the polychlorinated biphenyl of this invention. It is a figure which shows the other Example of the detoxification processing system of the electric equipment using the electric insulation oil containing the polychlorinated biphenyl of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Refiner 2 Transformer 3 Outlet 4 1st piping 5 Pump 6a Low concentration PCB
6b Refined electrical insulating oil 7 Caustic soda 8 Input port 9 Heater 10 Purifier main body 11 Container 12 Inlet 13 Catalyst 14 Reservoir 15 Hydrogen gas supply port 16 Hydrogen gas 17 Measuring device 18 Discharge port 19 Salt separation filter 20 Oil / water separator 21 Pump 22 Second piping 23 Oil storage tank 24 Fourth piping 25a Stop valve 25b Stop valve 26 Third piping 27 Inlet port 28 Nitrogen gas 29 Car 30 Tank truck

Claims (5)

  Electric equipment using electrical insulating oil containing polychlorinated biphenyl of more than 0.5mg / kg to 10000mg / kg or less, and in a hydrogen gas atmosphere, zeolite / nickel, nickel / molybdenum, nickel / platinum, etc. Detoxification treatment equipment for electrical insulation oil that dechlorinates, hydrogenates and renders polychlorinated biphenyl detoxified under a nickel-based catalyst, and detoxification treatment of the electrical insulation oil from the outlet at the substantially upper or lower end of the electrical equipment Polychlorinated biphenyls are produced by utilizing the dechlorination and hydrogenation reaction of the catalyst that occurs in the process of passing between the first pipe that removably connects the inlet of the apparatus and the catalyst in the hydrogen gas atmosphere. An oil storage tank for storing detoxified and refined electrical insulating oil and an oil storage tank for storing purified electrical insulating oil from the discharge port of the detoxifying treatment apparatus for the electrical insulating oil are detachably connected. And polychlorinated biphenyl constituted by a third pipe that detachably connects an inlet port substantially opposite to the outlet port of the electrical device from an oil storage tank that stores the refined electrical insulating oil. An electrical insulating oil detoxification treatment system, wherein the electrical insulation oil containing the polychlorinated biphenyl is injected from the electrical equipment into an inlet of the detoxification processing apparatus and passes between the catalysts in a hydrogen gas atmosphere. Polychlorinated biphenyl is detoxified using the dechlorination and hydrogenation reactions that occur during the process, and the refined electrical insulating oil is transferred to the oil storage tank from the discharge port opposite to the inlet of the detoxification device. Then, the refined electrical insulating oil [electric equipment → electric equipment outlet → first pipe] is connected by a third pipe that removably connects the inlet of the oil storage tank and the outlet of the electric equipment. → Injection of detoxification equipment → Catalyst under hydrogen gas atmosphere → Deleting port of detoxification treatment device → Second piping → Oil storage tank → Third piping → Electrical equipment inlet → Electric equipment] A system that renders electrical equipment that uses oil harmless.   In the invention of claim 1, a second pipe that circulates the purified electrical insulating oil from the discharge port of the detoxification treatment device to the oil storage tank to the injection port of the detoxification treatment device is branched from the second pipe that transfers the purified electrical insulating oil, A stop valve is disposed in each of the second pipe and the third pipe, and by opening and closing the stop valve, the electrical insulation oil in the course of purification is supplied from the discharge port to the detoxification treatment apparatus through the third pipe. Alternatively, the electrical insulating oil containing polychlorinated biphenyl according to claim 1, wherein the electrical insulating oil that has been refined to the oil storage tank is selected and circulated by the second pipe. System that renders the electrical equipment itself harmless.   The electric insulation oil detoxification treatment equipment is configured on-board, moved to the installation location of the electric equipment, and the electric equipment using the electric insulation oil containing polychlorinated biphenyl and the oil storage tank are connected on-site for electric insulation. The oil is detoxified, and after the detoxification treatment, the detoxification processing device is separated from the oil storage tank and the electrical equipment, and can be moved to a place different from the electrical equipment. A system for detoxifying electrical equipment itself using electrical insulating oil containing polychlorinated biphenyl according to claim 1 and claim 2.   4. A system for detoxifying electrical equipment itself using electrical insulating oil containing polychlorinated biphenyl according to claim 1, wherein a tank truck is applied to an oil storage tank.   Electric equipment using electrical insulation oil containing polychlorinated biphenyl of 0.5 mg / kg or more and 10000 mg / kg or less, and electrical insulation oil detoxification treatment equipment that dechlorinates, hydrogenates and detoxifies polychlorinated biphenyl Decontamination treatment of purified electrical insulation oil that has been detoxified in the process of being connected, injecting the electrical insulating oil from the electrical equipment to the inlet of the detoxification treatment device, and circulating in the detoxification treatment device The electrical insulation oil that is stored in the oil storage tank from the discharge port of the device and dripped into the electrical equipment is further recovered, injected into the injection port of the detoxification treatment device, and the refined electrical insulation oil stored in the oil storage tank is stored. A method for detoxifying an electrical device itself using an electrical insulating oil containing polychlorinated biphenyl by being refluxed to the electrical device.

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