JP2013208510A - Method for treating large-sized instrument contaminated with pcb and treatment device to be used for the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for treating a container that can be treated in a storage place in a large-sized high concentration instrument that is not easy to carry and is extremely hard to treat, and to provide a treatment device.SOLUTION: A method for treating a large-sized instrument contaminated with PCB is characterized by performing in parallel: a cleaning step of, while performing the circular cleaning of the inside of the large-sized instrument 1 contaminated with PCB by using a cleaning liquid, suitably extracting a predetermined amount of the cleaning liquid into a first buffer tank 2 from the cleaning liquid in use for cleaning, and newly supplying the cleaning liquid to the large-sized instrument 1 after the cleaning liquid is extracted to perform the circular cleaning; and a decomposition treatment step of transferring a part of the extracted cleaning liquid from the first buffer tank 2 to a feed liquid tank 3 for storing the cleaning liquid, adding an alkali to the cleaning liquid in the feed liquid tank 3, and then, while circulating the cleaning liquid through a catalyst filled device 4 that is filled with a PCB decomposition catalyst, irradiating the cleaning liquid with a microwave by a microwave treatment device 5 to decompose the PCB in the cleaning liquid, and returning the cleaning liquid circulated through the catalyst filled device to a treated liquid tank 6. A treatment device is used for the method for treating the large-sized instrument contaminated with PCB.

Description

  The present invention relates to a processing method for cleaning the inside of a container of a large device contaminated with PCB, and a disassembling and assembling processing apparatus used therefor.

  Among various PCBs, polychlorinated biphenyls (PCBs) are extremely harmful to living bodies including the human body, so transformers containing insulating oil containing PCBs are properly managed and stored according to the PCB Special Measures Law. Is required. About the equipment contaminated with those insulating oil and PCB, the detoxification process is being carried out one by one in the processing facility provided by the country or the electric power company.

  However, because there is a limit to the size of equipment that can be accepted by the processing facility, no processing technology has been established for large equipment that is not easy to carry, and in particular, it is difficult to handle containers for large, high-concentration equipment. There have been no examples of successful processing so far.

  Further, when processing by the microwave extraction decomposition method (see, for example, Patent Documents 1 and 2), if the PCB in the cleaning liquid is decomposed as it is in the catalytic reaction tank, the catalyst is fixed by alkali in the liquid and the decomposition reaction is caused. There is a problem that the catalyst tank has to be replaced because it does not progress.

  Furthermore, since undecomposed PCB remains in the exchanged catalyst, this PCB needs to be separately decomposed.

JP 2009-233654 A JP 2009-183838 A

  The present invention has been made in view of the above problems, and it is an object of the present invention to provide a container processing method and a processing apparatus that can be processed at a storage place for large-scale high-concentration equipment that is not easy to carry and extremely difficult to process. And

  As a result of intensive studies to solve the above-mentioned problems, the present inventors carry out in parallel a cleaning step by circulating a cleaning liquid of a large device and a PCB decomposition processing step for decomposing PCB in the cleaning liquid that has undergone the cleaning step. As a result, it was found that the catalyst was not fixed and the PCB decomposition treatment was continuously possible, and the present invention was achieved.

  That is, the present invention is as follows.

1) While circulating and washing the inside of the large equipment contaminated with PCB using the cleaning liquid, a predetermined amount of cleaning liquid is appropriately extracted from the cleaning liquid being cleaned into the first buffer tank, and the cleaning liquid is newly added to the large equipment after the cleaning liquid is extracted. A cleaning process for circulating and cleaning, and a part of the extracted cleaning liquid is transferred from the first buffer tank to a supply liquid tank for storing the cleaning liquid, and after adding alkali to the cleaning liquid in the supply liquid tank, the cleaning liquid In parallel with a decomposition treatment step of decomposing PCB in the cleaning liquid by irradiating microwaves while circulating the catalyst through the catalyst filling apparatus filled with the PCB decomposition catalyst, and returning the cleaning liquid after distribution to the processing liquid tank to the processing liquid tank A method of treating large equipment contaminated with PCB, characterized by:
2) After performing the cleaning process multiple times, instead of the cleaning process, a new cleaning liquid is added to the large equipment after the cleaning liquid is extracted, and the post-cleaning process is performed to circulate and wash between the large equipment and the first buffer tank. A method for treating a large-scale device contaminated with PCB according to 1),
3) The PCB concentration is measured with respect to the treatment liquid returned to the treatment liquid tank, and the treatment liquid that does not satisfy the regulation value is returned to the supply liquid tank again, and the filled treatment liquid is transferred to the second buffer tank. A method for treating large equipment contaminated with PCB as described in 1) or 2),
4) A method for treating a large device contaminated with PCB according to any one of 1) to 3), wherein a new cleaning liquid to be placed in the large device is supplied from a tank lorry.
5) A method for treating a large-sized device contaminated with PCB according to any one of 1) to 4), wherein the cleaning liquid to be placed in the large-sized device is isopropyl alcohol.
6) A dismantling process for disassembling parts of large equipment that has undergone a cleaning process to obtain a member, and then performing a wiping test, a cleaning liquid test or a member sampling test on the member, and recycling or discarding the member that satisfies the regulation value The member that is not filled further includes a dissolution step of immersing the member in the treatment liquid obtained in the decomposition treatment step to dissolve the PCB in the treatment solution. A processing method for large equipment contaminated with PCB.

7) Liquid circulation means for circulating the cleaning liquid inside the large equipment,
A first buffer tank for storing a cleaning liquid extracted from a large-sized device;
A supply liquid tank for storing the cleaning liquid transferred from the first buffer tank, a catalyst filling apparatus, a microwave processing apparatus, a processing liquid tank for storing the processing liquid after the decomposition treatment, and a microwave apparatus unit including a liquid circulation means,
A second buffer tank for storing the treatment liquid that has undergone the decomposition treatment step; and
Liquid feeding means for transferring cleaning liquid and processing liquid,
A disassembling and assembling processing device characterized by comprising:
8) The disassembly and assembly according to 7), further comprising: a cleaning tank that immerses a member that does not satisfy the regulation value; and a liquid feeding means that transfers the processing liquid in the processing liquid tank to the cleaning tank. Possible processing equipment.

According to the present invention, after the PCB inside the large equipment is eluted in the cleaning liquid, the cleaning liquid is appropriately extracted, the cleaning liquid is newly added, the large equipment is circulated and washed, and the alkali is added to the extracted cleaning liquid. Therefore, the PCB concentration in the extracted cleaning liquid can be controlled. As a result, a large amount of PCB decomposition reaction by-products (KCl, etc.) are generated during the decomposition treatment, and the phenomenon that the by-product accumulates on the catalyst makes it difficult for the catalyst to stick, and the PCB decomposition treatment continues. Can be performed for a long time. On the other hand, since the cleaning liquid can be added and the inside of the large equipment can be circulated and cleaned after draining the cleaning liquid, the processing can be completed by performing the container cleaning and the PCB decomposition process several times in parallel. .
In the decomposition processing step, since the supply liquid tank and the processing liquid tank are provided separately, it is possible to simultaneously receive the extracted cleaning liquid and transfer the processing liquid after the decomposition processing to the buffer tank. The cleaning liquid that has been subjected to the PCB decomposition process is sequentially transferred to the buffer tank, and after the final graduation judgment is carried out, it is dispensed and disposed as specially controlled industrial waste.

  In addition, since a processing device can be assembled and processed at a storage location for a large and high concentration device that is not easy to carry and extremely difficult to process, the processing device can be moved to each storage location for processing.

It is a processing flowchart which shows an example of the processing method of the large sized apparatus contaminated with PCB which concerns on this invention. It is a processing flowchart which shows the processing method of the large sized equipment contaminated with the conventional PCB. It is a graph which shows the relationship between the PCB decomposition processing days and PCB density | concentration in an Example and a comparative example.

  Hereinafter, a processing method and a processing apparatus for large equipment contaminated with PCB according to the present invention will be described in detail with reference to the drawings.

  Note that the large equipment contaminated with the PCB to be cleaned in the present invention is an arbitrary method in which the insulating oil containing PCB contained in the large equipment is drained, pumped, tilted drained, etc. In the state where the internal parts such as the coil are in use and the insulation oil containing PCB remains in a small amount, or a small amount of PCB remains in the residue after preliminary cleaning. It is a state of being.

  Examples of the large equipment include a pole transformer, a large transformer, and the like. Here, the large transformer mainly has an insulating oil capacity of 100L to 10,000L.

  Examples of PCBs to be decomposed include polychlorinated biphenyls (PCBs) and dioxins, and the types thereof are not particularly limited. PCBs include PCBs containing dioxins. Examples of commercially available PCBs include KC-200 (main component: biphenyl dichloride), KC-300 (main component: biphenyl trichloride), KC-400 (main component: tetrachloride) manufactured by Kaneka Chemical Co., Ltd. Biphenyl), KC-500 (main component: biphenyl pentachloride), KC-600 (main component: biphenyl bichloride), KC-1000 (KC-500 + benzene trichloride), KC-1300 (KC-300 + dichlorobenzene + tetrachlorobenzene) And Arochlor 1254 (54% Chlorine) manufactured by Mitsubishi Monsite Corporation.

  FIG. 1 is a process flow diagram showing an embodiment of a method for treating a large device contaminated with PCB according to the present invention. In FIG. 1, 1 is a large device contaminated with PCB, 2 is a first buffer tank that stores cleaning liquid extracted from the large device, 7 is a second buffer tank that stores processing liquid that has undergone a decomposition process, and 20 is a first buffer tank. 1 supply liquid tank 3 for storing the cleaning liquid transferred from the buffer tank 2, catalyst filling device 4, microwave processing device 5, processing liquid tank 6 for storing the processing liquid after decomposition processing, pumps 13 a, 13 b, A microwave apparatus unit having a liquid circulation means 13 such as pipes 13c and 13; 11 is a liquid circulation means for circulating a cleaning liquid inside the large-sized device 1 such as a pump 11a and a pipe 11b; 11c, 12, 14, 15, 17 Reference numerals 19 and 19 denote liquid feeding means for transferring the cleaning liquid and the processing liquid.

  As shown in the processing flow of FIG. 1, first, liquid circulation is performed in a high-pressure transformer (hereinafter referred to as “transformer”) 1 after removing the filled PCB insulating oil, which is a large device contaminated with PCB. The circulation pump 11 a and the circulation pipe 11 b which are means 11, and the pipe 19, the pump 2 a and the overflow pipe 10 which are liquid feeding means between the first buffer tank 2 are connected. For extracting the cleaning liquid from the transformer 1, a pipe 11c that connects the pipe 11b and the overflow pipe 10 is provided, the switching valve that connects each pipe is operated, and the pipe 11c is closed except when the cleaning liquid is extracted. Subsequently, a cleaning solution is put into the transformer 1. The cleaning liquid is charged until the transformer 1 is filled, and the overflowed cleaning liquid is stored in the first buffer tank 2 via the overflow pipe 10. Thereafter, the inside of the transformer 1 is circulated and washed using the liquid circulating means 11 and the PCB inside the transformer 1 is eluted into the washing liquid to start the washing process.

  The cleaning liquid is preferably supplied to the transformer 1 from the tank lorry 9 moved to the storage location via the liquid feeding means (pipe) 18. Thereby, the number of apparatus units carried to the storage place required for container processing can be suppressed to the minimum.

  As the cleaning liquid to be put into the transformer 1, a liquid based on a hydrogen donating solvent such as isopropyl alcohol is preferable. In order to reduce and decompose the PCB in the cleaning liquid, hydrogen is required. However, if hydrogen is supplied separately, an explosion-proof device is required and there is a concern about safety. However, if the cleaning liquid contains a hydrogen donor, it is not necessary to supply hydrogen separately. Therefore, the cleaning liquid is required to have two functions: a function as a solvent for dissolving PCB and a function as a hydrogen donor for decomposing PCB. As the hydrogen donating solvent, isopropyl alcohol is most preferable.

  As the circulation cleaning is performed, the PCB concentration in the cleaning liquid gradually increases. Then, when an appropriate PCB concentration suitable for PCB decomposition processing is reached, a predetermined amount of cleaning liquid is extracted from the cleaning liquid in the cleaning process to the first buffer tank 2 through the pump 11a and the pipes 11b, 11c, and 10. A cleaning liquid is newly added from the tank lorry 9 to the transformer 1 after the cleaning liquid is extracted, and the cleaning process is continuously performed while being circulated and cleaned by the liquid circulation means 11. The amount of the newly added cleaning solution is approximately the same as the amount of the extracted cleaning solution.

  The extraction of the cleaning liquid into the first buffer tank 2 and the addition of a new cleaning liquid into the transformer 1 are preferably performed about several times during the cleaning process. By adding a new cleaning solution, the PCB concentration in the cleaning solution circulating in the transformer 1 decreases once, but increases again as the circulating cleaning continues. As described above, as the number of times the cleaning liquid is extracted is increased, the PCB concentration in the cleaning liquid gradually decreases while increasing and decreasing.

  While performing the cleaning process, a part of the cleaning liquid extracted into the first buffer tank 2 is transferred to the supply liquid tank 3 using the pump 2a and the liquid supply means (pipe) 12. A predetermined amount of alkali is added to the cleaning liquid transferred to the supply liquid tank 3.

  The alkali is preferably KOH or NaOH from the viewpoint of high dehalogenation efficiency and excellent cost and handling properties, and can be used alone or in combination of two or more. Alkali serves as a neutralizing agent that neutralizes chlorine released by the decomposition of PCB. Therefore, even if the amount of the neutralizing agent is too large, the economy is inferior, and when it is too small, the reaction rate decreases. The alkali is preferably 1.0 to 1.5 times equivalent (more preferably 1.1 to 1.2 times equivalent) to the halogen of PCB in the cleaning liquid.

  Then, while circulating the cleaning liquid in the supply liquid tank 3 to which the alkali has been added to the catalyst filling device 4 filled with the PCB decomposition catalyst, the microwave in the cleaning liquid is irradiated with microwaves to decompose the PCB in the cleaning liquid. A decomposition process step is performed. The decomposition process is performed using a microwave device unit 20 that can be carried, assembled, and disassembled.

  The microwave device unit 20 includes a supply liquid tank 3, a catalyst filling device 4 including a microwave processing device 5, a processing liquid tank 6, and a liquid circulation means 13 including pumps 13a and 13b, pipes 13c and 13d, and the like. Is done. One unit is preferably provided with a catalyst filling device 4 including a plurality of microwave processing devices 5 from the viewpoint of improving processing efficiency. In the decomposition process, one or a plurality of microwave device units 20 can be used.

  In the decomposition processing step, the cleaning liquid in the supply liquid tank 3 is irradiated to the microwave by the microwave processing apparatus 5 while being circulated through the catalyst filling apparatus 4 using the pump 13a, and the cleaning liquid in the cleaning liquid at normal pressure and 60 ° C. PCB should be disassembled (Japanese Patent Laid-Open No. 2009-233654). When the cleaning liquid is circulated through the catalyst filling device 4, the decomposition of the PCB can be promoted by irradiating the cleaning liquid with microwaves in the catalyst filling device 4. The microwave may be irradiated continuously or intermittently. In this case, the output and frequency of the microwave can be appropriately determined according to the cleaning conditions to be set, but irradiation is performed in the range of 10 W to 20 kW while electrically controlling the microwave of frequency 1 to 300 GHz. Is preferred. The liquid temperature at the time of washing is preferably normal temperature or higher and 60 ° C. or lower. This is because if the temperature is lower than normal temperature, the decomposition time of the PCB is slow, so that the processing time becomes long.

  Any catalyst can be used for the catalyst filling device 4 as long as it can accelerate the dehalogenation reaction of PCB, and the type thereof is not particularly limited. An inorganic catalyst is preferable to an organic catalyst because it has a long catalyst life and is stable even in the presence of an alkali compound. The inorganic catalyst is preferably a composite metal oxide, a carbon crystal compound, a metal-supported carbon compound, a metal-supported oxide, a metal-supported composite metal oxide, or a metal oxide from the viewpoint of increasing the dehalogenation efficiency. Particularly preferred are metal-supported carbon compounds that are highly safe in an alkaline atmosphere and have high microwave absorption. These catalysts can be used alone or in any combination of two or more, and may be regenerated catalysts regenerated after use.

  The metal-supported carbon compound may be a carbon compound supporting a metal, but the metal support amount is preferably 0.1 to 20 wt%, more preferably 0.1 to 10 wt% with respect to the total amount of the catalyst. Examples of the supported metal include iron, silver, platinum, ruthenium, palladium, and rhodium. From the viewpoint of increasing the dehalogenation efficiency, palladium, ruthenium, and platinum are preferable, and palladium is particularly preferable. Specific examples of the metal-supported carbon compound include Pd / C (palladium-supported carbon compound), Ru / C (ruthenium-supported carbon compound), Pt / C (platinum-supported carbon compound), and the like.

  The amount of catalyst used may be appropriately determined depending on the type of cleaning object (large equipment) and the degree of contamination. If the amount of the catalyst is too small, the decomposition efficiency of the PCB is deteriorated, so that the cleaning time becomes longer or the catalyst needs to be replaced during the cleaning, which is inefficient. On the other hand, too much catalyst is uneconomical. Usually, it is preferable to use about 0.5 to 5.0% of the catalyst (weight) with respect to the cleaning liquid (volume).

  In the decomposition processing step, the PCB concentration of the processing liquid once circulated to the processing liquid tank 6 is measured. And the process liquid which does not satisfy | fill a regulation value is made to circulate through the catalyst filling apparatus 4 again by returning to the supply liquid tank 3 via the piping 13d using the pump 13b. Such a continuous decomposition treatment is performed until the PCB concentration in the cleaning liquid becomes a regulation value (0.5 ppm) or less.

  By providing the supply liquid tank 3 and the treatment liquid tank 6 separately, the reception of the washing liquid during the washing process and the transfer of the treatment liquid after the PCB decomposition process can be performed at the same time. Processing can be carried out continuously.

  That is, the processing liquid whose PCB concentration has become equal to or lower than the regulation value by the decomposition processing is transferred from the processing liquid tank 6 to the second buffer tank 7 through the liquid supply means (pipe) 14 using the pump 13b. . During this time, a predetermined amount of cleaning liquid is extracted from the first buffer tank 2, transferred to the supply liquid tank 3 via the pump 2 a and the pipe 12, and an operation of adding alkali can be performed. The PCB decomposition process can be carried out subsequently.

  Extraction of the cleaning liquid from the transformer 1 to the first buffer tank 2 during the cleaning process described above, addition of new cleaning liquid into the transformer 1 after the extraction and circulation cleaning, and transfer to the supply liquid tank 3 The PCB decomposition treatment in the cleaning liquid is performed several times according to the capacity of the transformer 1 until the PCB concentration in the cleaning liquid circulating in the transformer 1 becomes a predetermined concentration (about 10 ppm) or less.

As described above, in the processing apparatus of the present invention, the liquid circulating means 11 (which includes the circulation pump 11a and the circulation pipe 11b) that circulates the cleaning liquid in the transformer 1 and the second cleaning liquid that has finished the PCB decomposition process are stored. Since the buffer tank 7 is provided, since the circulation of the cleaning liquid in the transformer 1 and the decomposition process of the PCB in the cleaning liquid can be performed in parallel, the PCB processing efficiency is improved. Further, when the transformer 1 is circulated and cleaned, an unused cleaning solution can be added, and the cleaning efficiency of the transformer 1 is improved. From this point, the PCB processing efficiency can be improved.
On the other hand, in the conventional apparatus having only the first buffer tank 2 as shown in FIG. 2, for example, a part of the cleaning liquid in the first buffer tank 2 is extracted and transferred to the supply liquid tank 3 to be subjected to PCB decomposition processing. When performing the above, the circulation cleaning of the transformer 1 must be stopped while the cleaning liquid is being extracted from the first buffer tank 2. In addition, since the processing liquid after the PCB decomposition process is returned to the first buffer tank 2, it is difficult to circulate and clean the transformer 1 by adding an unused cleaning liquid.

  Since the processing liquid stored in the second buffer tank 7 contains, in addition to the cleaning liquid, biphenyl, acetone, benzene, water, neutralized salts (KCl, etc.) that are by-produced by the added alkali or PCB decomposition process, After the graduation judgment, it will eventually be dispensed and disposed as specially managed industrial waste.

  The processing liquid stored in the second buffer tank 7 is supplied to the supply liquid tank 3 through the pipe 12 by the pump 7a, so that the processing liquid is extracted from the first buffer tank 2 and sent to the decomposition processing step. Can be used to adjust PCB concentration. Or it can supply to the washing tank 8 via the piping 15 with the pump 7a, and can also be used for washing | cleaning of the disassembly member mentioned later.

  After the initial concentration of PCB is lowered by performing the cleaning process several times, instead of performing the above-described cleaning process, a new cleaning liquid is put into the transformer 1 after the cleaning liquid is extracted, and the transformer 1 and the first buffer tank A post-cleaning step of circulating cleaning with 2 can be performed. Also in the post-cleaning step, a part of the cleaning liquid is extracted, and a part of the extracted cleaning liquid is transferred from the first buffer tank 2 to the supply liquid tank 3 that stores the cleaning liquid, and the cleaning liquid in the supply liquid tank 3 is alkalinized. Is added to the catalyst filling device 4 filled with the PCB decomposition catalyst, microwaves are irradiated from the microwave treatment device 5 to decompose PCB in the cleaning solution, and the cleaning solution after the catalyst filling device 4 is distributed. The decomposition treatment step for returning the liquid to the treatment liquid tank 6 is performed in parallel.

  In the post-cleaning step, the cleaning liquid is extracted, the cleaning liquid added to the transformer 1 after the extraction and circulation cleaning, and the PCB decomposition process in the cleaning liquid transferred to the supply liquid tank 3 are circulated in the transformer 1. This is carried out until the PCB concentration in the inside becomes a predetermined concentration (about 10 ppm) or less.

  The transformer 1 that has undergone the above-described cleaning process or post-cleaning process draws the cleaning liquid from the transformer 1, drains the cleaning liquid, and then disassembles it into an iron container and the components that are present inside. Internal parts such as coils are broken down into iron cores, coils (copper wires), and insulators, and the coils are crushed and then broken down into copper, paper, wood, etc. to obtain members. Thereafter, the member is subjected to a wiping test, a cleaning liquid test or a member sampling test, and a member satisfying the regulation value is recycled or discarded. On the other hand, a member that does not satisfy the regulation value is immersed in the treatment liquid obtained in the above decomposition treatment step to dissolve PCB in the treatment liquid. The processing liquid in which PCB is dissolved is returned again to the supply liquid tank 3 and is put into the second buffer tank 7 through the PCB decomposition processing step.

  A cleaning tank 8 is used for dipping a member that does not satisfy the regulation value. The processing liquid is supplied to the cleaning tank 8 (about 5000 L) by extracting the processing liquid in the processing liquid tank 6 with the pump 13 b and via the liquid feeding means (piping) 16. Alternatively, the processing liquid in the second buffer tank 7 is extracted by the pump 7 a and is supplied via the liquid feeding means (pipe) 15. In the immersion cleaning of the member, if the processing liquid in the cleaning tank 8 is circulated using the pump 8a and the liquid feeding means (pipe) 17, the cleaning efficiency is further improved. Each member after cleaning is checked by analysis to determine whether or not each member satisfies a predetermined graduation standard value. Members that meet the regulatory values are recycled or discarded.

  The processing apparatus used in the container processing method of the present invention is composed of a plurality of units that can be carried, assembled, and disassembled. The first buffer tank 2 stores cleaning liquid during the cleaning process, and the microwave apparatus unit 20 includes cleaning liquid. The PCB inside is decomposed, the second buffer tank 7 stores the processing solution that has undergone the decomposition processing step, and the cleaning tank 8 is for dip cleaning a member that does not satisfy the regulation value. And in this invention, each apparatus unit is conveyed to the storage place of the large sized equipment contaminated with PCB, and the liquid circulation means to circulate the cleaning liquid, the cleaning liquid and the processing liquid are transferred to each apparatus unit at the storage place. A processing apparatus is constructed by installing and assembling other necessary apparatuses by attaching liquid feeding means.

  After the container processing is completed, the processing liquid in the second buffer tank 7 is dispensed and disposed as special management industrial waste. Further, after disassembling, the processing apparatus is transported and assembled to another storage location, and used for container processing of large equipment contaminated with PCB present in the storage location.

  EXAMPLES Next, although an Example demonstrates this invention concretely, this invention is not limited only to a following example. In the following examples and the like, “mass%” is abbreviated as “%” unless otherwise specified.

(Comparative example)
Container processing was performed according to the processing flow shown in FIG. The supply liquid tank 3, the processing liquid tank 6, the catalyst filling device 4, and the microwave processing device 5 constituting the microwave device unit 20 in FIG. 2 have the same specifications as those in FIG.

  The piping 19 between the first buffer tank 2, the pump 2 a, and the 2500 L large-sized high-pressure transformer 1 (with a residual oil amount of about 70 L (including the amount of impregnation into insulating paper)) from which PCB insulating oil has been drained in advance The overflow pipe 10 was connected.

  Subsequently, isopropyl alcohol (IPA) previously received in the first buffer tank was put into the high-pressure transformer 1 through the pipe 19 and the circulation pump 2a so that the inside of the high-pressure transformer was filled with IPA. Thereafter, a circulation operation is performed between the high-pressure transformer 1 and the first buffer tank 2, and at the same time, a part of the circulating cleaning liquid is extracted, transferred to the supply liquid tank 3, and a predetermined amount of KOH is added to the supply liquid tank (KOH is After being dissolved in an appropriate amount of IPA in advance and transferred to the microwave device unit 20 to decompose the PCB, it was returned to the first buffer tank 2 via the treatment liquid tank 6 and the pipe 14.

  During the period during which the container cleaning process is being performed, the PCB concentration in the cleaning liquid was measured, and the container cleaning process was performed until the PCB concentration reached a predetermined value (about 10 ppm) or less. The relationship between the number of treatment days and the PCB concentration is shown in Run 1 of FIG.

  The PCB concentration was analyzed using a gas chromatography mass spectrometer QP5050A manufactured by Shimadzu Corporation using polysiloxane DB-5MS (column length: 30 m) (manufactured by Agilent Technologies) as a capillary column.

(Example)
Container processing was performed according to the processing flow shown in FIG.

  On the main body side of the 2500 L large-sized high-pressure transformer 1 (residual oil amount is approximately 70 L (including the amount of impregnation into insulating paper)) from which PCB insulating oil has been drained in advance, the circulation pipe 11 b, the circulation pump 11 a, and the first A pipe 19 between the buffer tank 2, a pump 2 a, and an overflow pipe 10 were connected. In addition, a pipe 11c that connects the circulation pipe 11b and the overflow pipe 10 is provided.

  Subsequently, 3500 L of isopropyl alcohol (IPA) as a cleaning liquid was put into the transformer 1, the inside of the transformer was filled with IPA, and excess IPA was stored in the first buffer tank 2 via the overflow pipe 10. Thereafter, the IPA in the transformer 1 was appropriately circulated through the circulation pump 11a and the circulation pipe 11b.

  When the PCB concentration in the IPA reached about 10,000 ppm, 4000 L of the cleaning liquid in the transformer 1 was extracted into the first buffer tank 2 (5000 L capacity). In addition, new IPA of approximately the same amount as the amount of the extracted cleaning liquid was directly fed into the transformer 1 from the tank lorry 9, and the circulation by the circulation pump 11a and the circulation pipe 11b was continued.

  On the other hand, a part of the cleaning liquid extracted into the first buffer tank 2 was transferred to the 200-L supply liquid tank 3. Further, KOH was added to the supply liquid tank 3 so that the amount of KOH was 5000 g with respect to 250 L of the cleaning liquid.

  Subsequently, liquid was passed through six treatment apparatuses installed outside the supply liquid tank 3 using a circulation pump 13a for microwave decomposition at a circulation rate of 6 L / min. The said processing apparatus is comprised from the catalyst filling apparatus 4 and the microwave processing apparatus 5, microwave power is a maximum of 1 kW, and a processing tank capacity | capacitance is about 50L in total. In the processing apparatus, each microwave processing apparatus 5 was allowed to pass through a catalyst filling apparatus 4 (catalyst amount 2 kg × 6 units) filled with activated carbon catalyst supporting palladium while irradiating microwaves, and then the cleaning liquid was 200 L in volume. A circulation operation was performed by collecting the liquid in the treatment liquid tank 6 and returning it to the supply liquid tank 3 using the feedback pump 13b. In the decomposition treatment, the liquid was circulated by irradiation with microwaves while maintaining the treatment temperature at 60 ° C. When the PCB concentration in the circulated liquid became 0.5 ppm or less, the circulation operation was stopped, and the treatment liquid was transferred to the second buffer tank 7 (5000 L capacity) using the pump 13b.

  Extraction of the cleaning liquid into the first buffer tank 2, addition of KOH in the supply liquid tank 3 (described in paragraph number [0056]), and PCB decomposition processing (described in paragraph number [0057]) using the microwave device unit 20 Repeatedly, all the cleaning liquid in the first buffer tank 2 was processed. During the PCB decomposition treatment process, the cleaning process for circulating the cleaning liquid in the transformer 1 through the circulation line 11b and the circulation pump 11a was continued.

  When the PCB concentration in the cleaning liquid in the transformer 1 reaches about 100 ppm when a new cleaning liquid (IPA) is added, the circulation of the cleaning liquid is switched to the circulation between the transformer 1 and the first buffer tank 2. A washing step was performed. While circulating cleaning, the cleaning liquid was extracted, the KOH addition in the supply liquid tank 3 and the PCB decomposition process using the microwave device unit 20 were repeated to process all the cleaning liquid.

  The cleaning liquid in the transformer 1 was extracted and transferred to the supply liquid tank 3 until the PCB concentration in the circulating liquid became a predetermined value (about 10 ppm) or less. All the treatment liquid after the decomposition treatment was transferred to the second buffer tank 7.

  During the container cleaning process, the PCB concentration in the cleaning liquid in the transformer 1 was measured. The relationship between the number of treatment days and PCB concentration is shown in Run 2 of FIG.

  FIG. 3 shows that according to the container processing method of the present invention, the container processing of the large equipment contaminated with PCB can be completed in about half the conventional processing days.

  The processing method and processing apparatus according to the present invention can be disassembled and assembled, and can be moved and processed at each storage location. Therefore, the processing method and the processing apparatus according to the present invention exhibit extremely excellent effects on the container processing of large equipment contaminated with PCB that is not easy to carry. .

1 Large equipment (high voltage transformer) contaminated with PCB
2 1st buffer tank 2a Pump 3 Supply liquid tank 4 Catalyst filling device 5 Microwave treatment device 6 Treatment liquid tank 7 Second buffer tank 7a Pump 8 Washing tank 8a Pump 9 Tank lorry 10 Overflow piping 11 Liquid circulation means 11a Pump 11b Piping 11c Piping 12 Piping 13 Liquid circulating means 13a, 13b Pumps 13c, 13d Piping 14 Piping 15 Piping 16 Piping 17 Piping 18 Piping 19 Piping 20 Microwave device unit

Claims (8)

  While circulating and cleaning the inside of the large equipment contaminated with PCB using the cleaning liquid, a predetermined amount of cleaning liquid is appropriately extracted from the cleaning liquid being cleaned into the first buffer tank, and the cleaning liquid is newly added to the large equipment after the cleaning liquid is extracted. The cleaning process for circulating cleaning and a part of the extracted cleaning liquid are transferred from the first buffer tank to the supply liquid tank for storing the cleaning liquid, and after adding alkali to the cleaning liquid in the supply liquid tank, the cleaning liquid is added to the PCB. In parallel with the decomposition process step, the PCB in the cleaning liquid is decomposed by irradiating microwaves while circulating through the catalyst filling apparatus filled with the decomposition catalyst, and the cleaning liquid after distribution through the catalyst filling apparatus is returned to the processing liquid tank. A method for treating large equipment contaminated with PCB.   After performing the cleaning process a plurality of times, instead of the cleaning process, a new cleaning liquid is put into the large equipment after the cleaning liquid is extracted, and a post-cleaning process is performed for circulating cleaning between the large equipment and the first buffer tank. The processing method of the large sized equipment contaminated with PCB of Claim 1 characterized by these.   The PCB concentration is measured with respect to the treatment liquid returned to the treatment liquid tank, the treatment liquid that does not satisfy the regulation value is returned to the supply liquid tank again, and the filled treatment liquid is transferred to the second buffer tank. A method for treating a large device contaminated with PCB according to claim 1 or 2.   The method for treating a large device contaminated with PCB according to any one of claims 1 to 3, wherein a new cleaning liquid to be introduced into the large device is supplied from a tank lorry.   The method for treating a large-sized device contaminated with PCB according to any one of claims 1 to 4, wherein the cleaning liquid put into the large-sized device is isopropyl alcohol.   A dismantling process for disassembling parts of large equipment that has undergone a cleaning process to obtain a member, and thereafter performing a wiping test, a cleaning liquid test or a member sampling test on the member, and recycling or discarding the member that satisfies the regulation value, The PCB according to any one of claims 1 to 5, further comprising a dissolving step in which the unsatisfied member is immersed in the treatment liquid obtained in the decomposition treatment step and the PCB is dissolved in the treatment liquid. How to handle contaminated large equipment. Liquid circulation means for circulating cleaning liquid inside large equipment,
A first buffer tank for storing a cleaning liquid extracted from a large-sized device;
A supply liquid tank for storing the cleaning liquid transferred from the first buffer tank, a catalyst filling apparatus, a microwave processing apparatus, a processing liquid tank for storing the processing liquid after the decomposition treatment, and a microwave apparatus unit including a liquid circulation means,
A second buffer tank for storing the treatment liquid that has undergone the decomposition treatment step; and
Liquid feeding means for transferring cleaning liquid and processing liquid,
A disassembling and assembling processing apparatus characterized by comprising:   The disassembly and assembly according to claim 7, further comprising: a cleaning tank that immerses a member that does not satisfy the regulation value; and a liquid feeding unit that transfers the processing liquid in the processing liquid tank to the cleaning tank. Processing equipment.

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