JP6830046B2 - PCB processing method - Google Patents

Description

The present invention relates to a PCB processing method for detoxifying a capacitor.

Conventionally, a PCB processing method in which the upper part of a capacitor is cut with a rotary blade, the element is taken out from the metal housing, the metal housing and the element are separated, and the metal housing and the element are individually washed and the removed PCB is chemically treated. Is disclosed (see, for example, Patent Documents 1 and 2).

In the PCB processing method described in Patent Document 1, after making a hole in a capacitor and draining oil, the upper part of the capacitor is cut with a rotary blade, and the element taken out from the metal housing is cut into round slices for cleaning and drying. The element is further crushed and washed again. The PCB processing method described in Patent Document 2 is to cut the upper part of a capacitor with a rotary blade, crush, clean, and vacuum-heat an element taken out from a metal housing.

Japanese Unexamined Patent Publication No. 2006-150277 Japanese Unexamined Patent Publication No. 2001-179231

In the conventional PCB processing method, the upper part of the capacitor is cut with a rotary blade to take out the element from the metal housing. However, since the small capacitors included in the ballast are small and enormous in quantity, they are individually used. It is extremely difficult to take out the element from the metal housing by positioning and cutting the upper part of the capacitor. In particular, the PCB processing method described in Patent Document 1 has poor work efficiency because the taken-out element is sliced and then further crushed.

Therefore, a PCB processing method capable of efficiently detoxifying a small capacitor contained in a ballast is desired.

The PCB processing method is a PCB processing method for detoxifying a capacitor having a metal case and an element housed in a ballast, and is a cutting step of injecting a cleaning solvent onto the surface of the capacitor to cut the capacitor. The metal case is provided with a separation step of separating the first fragment of the metal case into a second cut piece of the element, and a chemical treatment step of chemically treating the PCB contained in the second cut piece to make it harmless. ..

In this method, since the capacitor is cut by injecting a cleaning solvent, the capacitor containing PCB can be cleaned at the same time as cutting. At this time, since the cleaning solvent penetrates into the inside of the capacitor and cleans while diluting the PCB oil contained in the capacitor, it is not necessary to drain the PCB oil before the cutting process as in the conventional case, and the volatilization of the PCB is prevented. While achieving high cleaning efficiency. PCBs are mixed in this cleaning solvent, but since the PCBs contained in the cleaning solvent can be easily separated by distillation or the like, the work efficiency is extremely high.

In addition, since the first fragment of the metal case and the second cut piece of the element are separated in the sorting step, the low-concentration PCB detoxification treatment contained in the first fragment of the metal case and the second cutting of the element are performed. It is possible to separately carry out the high-concentration PCB detoxification treatment contained in the piece. Therefore, the metal case can be recycled and the PCB contained in the device can be chemically treated to reliably detoxify the device. Moreover, since it is equipped with a separation process for separating the first fragment of the metal case and the second cut piece of the element, it is necessary to position the upper part of the capacitor and then cut it to take out the element from the metal case as in the conventional case. There is no. As a result, it is possible to cut a large number of capacitors at the same time in the cutting process, and the work efficiency is extremely high.

As described above, it has been possible to provide a PCB processing method capable of efficiently detoxifying a small capacitor contained in a ballast.

In another method, in the separation step, the first fragment and the second cut piece may be separated by specific gravity separation, metal separation, or centrifugal filtration.

If the second cut piece of the element is separated by specific gravity separation by utilizing the fact that the specific gravity of the second cut piece of the element is smaller than that of the first fragment of the metal case as in this method, the separation step is extremely easy. In addition, as a sorting step, the same method is used to separate the first piece of the metal case into metal with a metal sorter, or to apply centrifugal force to separate the first piece and the second piece (centrifugal filtration). Easy to use.

The other method may further include a cleaning step of immersing the second cutting piece in the cleaning solvent used in the cutting step to clean the second cutting piece before the chemical treatment step. ..

In this method, in addition to cleaning the capacitor in the cutting process, if the second cut piece of the element is immersed in the cleaning solvent used in the cutting process for cleaning, the element is cleaned using another cleaning solvent, as compared with the case where the element is cleaned with another cleaning solvent. The processing cost can be reduced. This cleaning step is efficient because it can be realized by providing a storage tank for the cleaning solvent in the lower part of the apparatus used in the cutting step, for example.

In another method, the cleaning step may be reused by distilling the cleaning solvent.

If the cleaning solvent is distilled as in this method, it becomes a cleaning solvent having a low PCB concentration, and if this cleaning solvent is reused in the cleaning process, it is not necessary to add a new cleaning solvent and the processing cost can be further reduced. ..

It is a schematic diagram which shows the ballast. It is a flow chart of the PCB processing method which concerns on this embodiment. It is the schematic which shows the cutting process which concerns on this Embodiment.

Hereinafter, embodiments of the PCB processing method according to the present invention will be described with reference to the drawings. In the present embodiment, as a PCB processing method, an example of detoxifying a small capacitor 22 included in the ballast 2 by chemical treatment will be described. However, the present invention is not limited to the following embodiments, and various modifications can be made without departing from the gist thereof.

As shown in FIGS. 1 to 3, the PCB processing method according to the present embodiment detoxifies the capacitor 22 having the metal case 22a and the element 22b housed in the ballast 2. This PCB processing method includes a cutting step of injecting a cleaning solvent 13 onto the surface of the capacitor 22 to cut the capacitor 22, and separating the first fragment 23 of the metal case 22a and the second cutting piece 24 of the element 22b. It includes a step and a chemical treatment step of chemically treating the PCB contained in the second cut piece 24 to make it harmless. Further, it is preferable to include a cleaning step of immersing the second cutting piece 24 in the cleaning solvent 13 used in the cutting step to clean the second cutting piece 24 of the element 22b before the chemical treatment step.

As shown in FIG. 1, the ballast 2 has a transformer portion 21 including an iron core and insulating paper wound with a magnetic coil, and a capacitor 22 containing PCB as insulating oil. The ballast 2 is housed in a case 26 made of a material such as iron in a state where a filler 25 such as asphalt is filled between the transformer portion 21 and the capacitor 22.

The capacitor 22 has a metal case 22a made of aluminum or the like, and an element 22b housed in the metal case 22a and impregnated with PCB. In the element 22b, aluminum foil and insulating paper are alternately laminated.

As shown in FIG. 2, first, the case 26 is removed from the ballast 2 received by using a tool such as a screwdriver or a hammer, the filler 25 is roughly removed, and each member such as the transformer portion 21 and the capacitor 22 is disassembled. , Take out the capacitor 22 from the ballast 2. Next, as shown in FIG. 3, the capacitor 22 is placed on the transfer lane R, the capacitor 22 is transferred to just below the nozzle 11 of the cutting device 1, and the transfer lane R is stopped. Next, the cutting device 1 injects a hydrocarbon-based cleaning solvent 13 mixed with an abrasive onto the surface of the capacitor 22 at high pressure to cut the capacitor 22 into strips (cutting step). The cutting device 1 includes a movable portion 12 that can move in an XY plane parallel to the surface of the condenser 22, and a nozzle 11 that is connected to the movable portion 12 and ejects the cleaning solvent 13. While the nozzle 11 is moved in the XY plane parallel to the surface of the condenser 22 by the movable portion 12, the cleaning solvent 13 is jet-injected onto the surface of the condenser 22 to cut it into strips. At this time, the method of moving the nozzle 11 when cutting the capacitor 22 is not particularly limited, and the nozzle 11 may be moved vertically or diagonally other than the XY plane, and a large number of capacitors 22 are randomly placed on the transport lane R. It may be cut at the same time in the placed state. In the present embodiment, since the cleaning solvent 13 is jet-injected to cut the capacitor 22, the metal case 22a bites into the blade of the crusher as in the case of crushing using a crusher, for example, and the crushing efficiency is improved. There is no such thing as a decrease. Instead of the method of moving the movable portion 12 to the XY plane to cut the capacitor 22, the capacitor 22 is moved to the XY plane by the transport lane R with the position of the nozzle 11 fixed, and the capacitor 22 is cut. Alternatively, the nozzle 11 may be movablely configured to cut the capacitor 22. Further, a plurality of nozzles 11 may be prepared and cut while moving the capacitor 22 by the transport lane R.

Next, as shown in FIGS. 2 to 3, the strip-shaped cutting pieces 23 and 24 cut with the cleaning solvent 13 are transferred in the transport lane R, and the same cleaning solvent 13 used in the cutting step is stored. Drop it into the storage tank 4. At this time, the first fragment 23 of the metal case 22a having a relatively large specific gravity sinks to the bottom of the storage tank 4, and the second cut piece 24 of the element 22b having a relatively small specific gravity floats on the surface of the storage tank 4. (Separation process, specific gravity separation). As described above, in the present embodiment, specific gravity separation by the difference in specific gravity is used in order to separate the first fragment 23 of the metal case 22a and the second cut piece 24 of the element 22b. Therefore, the sorting process is extremely easy.

The sorting step may be carried out by the following method.
(1) A known aluminum sorter or the like that generates an eddy current in aluminum to repel it is arranged on the downstream side of the cutting device 1 in the transport direction of the transport lane R, and the first fragment 23 and the element of the metal case 22a are arranged. A method of separating into the second cut piece 24 of 22b (separation step, metal separation).
(2) With the grid-like partition members arranged inside the storage tank 4, a rotational force is applied to the stored cleaning solvent 13, and the metal case 22a having a relatively large volume inside the partition members A method using centrifugal filtration in which all the fragments 23 are separated and the second cut piece 24 of the element 22b having a relatively small volume is separated on the outside of the partition member (separation step, centrifugal filtration).
In each of the above-mentioned sorting methods, in order to facilitate sorting, the storage tank 4 may be subjected to a process of applying ultrasonic vibration.

Next, the first fragment 23 of the metal case 22a and the second cut piece 24 of the element 22b are immersed in the cleaning solvent 13 stored in the storage tank 4 for a predetermined time for primary cleaning (cleaning step). At this time, in the case of the method (1) above, only the second cut piece 24 of the element 22b is primarily washed with the cleaning solvent 13 stored in the storage tank 4, and the first fragment of the separated metal case 22a is separated. 23 will be primarily cleaned at another location. The cleaning method is not limited to immersion cleaning, and ultrasonic cleaning or stirring cleaning as in the method (2) above may be used in combination.

The cleaning step in the present embodiment includes a reuse step of distilling and reusing the cleaning solvent 13. Specifically, the on-off valve V and the distillation apparatus 3 are arranged in the circulation path 30 connected to the bottom of the storage tank 4 and the upper part of the storage tank 4. A predetermined amount of the cleaning solvent 13 containing PCB stored in the storage tank 4 is moved to the distillation apparatus 3 by opening the on-off valve V. Then, the distillation apparatus 3 heats the cleaning solvent 13 above the boiling point of the cleaning solvent 13 and below the boiling point of the PCB to separate the PCB oil into the distilled cleaning solvent 13, and cools the cleaning solvent 13 to form the storage tank 4. Recirculate and reuse. On the other hand, the separated PCB oil is detoxified by chemical treatment (chemical treatment step). This chemical treatment is carried out by dechlorination and decomposition using, for example, SD (Sodium Dispersion) in which metallic sodium is made into fine particles of less than 10 μm and dispersed in a dispersion solvent composed of a normal paraffin solvent or the like. The chemical treatment step is not limited to the dechlorination decomposition method using SD, and may be a liquid treatment such as a dechlorination decomposition method by a hydrogenation dechlorination purification method or a hydrothermal oxidative decomposition method.

Next, the first fragment 23 of the metal case 22a separated from the storage tank 4 and the second cut piece 24 of the element 22b are taken out, respectively, and transferred to the secondary cleaning step. In the secondary cleaning step, as in the primary cleaning step described above, the first fragment 23 of the metal case 22a is cleaned with a hydrocarbon-based cleaning solvent stored in a cleaning tank (not shown), and another The second cut piece 24 of the element 22b is cleaned with a hydrocarbon-based cleaning solvent stored in the cleaning tank. In the secondary cleaning step, immersion cleaning, stirring cleaning, ultrasonic cleaning, and the like are performed alone or in combination as appropriate. Also in this secondary cleaning step, the cleaning solvent and PCB oil are distilled and separated, the cleaning solvent is reused, and the PCB oil is chemically treated by dechlorination and decomposition as described above to make it harmless (chemical treatment). Process).

Since the PCB concentration of the first fragment 23 of the metal case 22a is relatively low, it can be easily detoxified by a cleaning step. Therefore, the graduation determination of whether or not the PCB concentration of the first fragment 23 after the secondary washing is equal to or less than the reference value (for example, 0.03 mg / L, which is the graduation standard of PCB) is executed, and it is considered to be harmless. Judged items are reused as resources or landfilled and paid out. On the other hand, if the PCB concentration of the first fragment 23 exceeds the reference value, the secondary cleaning step is executed again.

On the other hand, since the second cut piece 24 of the element 22b is impregnated with PCB, it is difficult for the PCB concentration to fall below the reference value by the cleaning step. Therefore, the second cut piece 24 of the element 22b is subjected to a vacuum heating separation step of evaporating and removing the PCB. The separated PCB is cooled and recovered as a liquid (PCB oil), and then chemically treated by dechlorination and decomposition as described above to make it harmless (chemical treatment step). Next, a graduation determination is performed as to whether or not the PCB concentration of the second cut piece 24 is equal to or less than the reference value, and those determined to be harmless are disposed of by landfill or incineration. On the other hand, when the PCB concentration of the second cut piece 24 exceeds the reference value, the secondary cleaning step and the vacuum heating separation step are executed again.

In the present embodiment, since the capacitor 22 is cut by jet-injecting the cleaning solvent 13, the capacitor 22 containing the PCB can be cleaned at the same time as the cutting. At this time, since the cleaning solvent 13 is injected onto the surface of the condenser 22, the cleaning solvent 13 permeates into the inside of the condenser 22, and the cleaning efficiency is high. PCB is mixed in the cleaning solvent 13, but the PCB contained in the cleaning solvent 13 can be easily separated by distillation or the like, so that the work efficiency is extremely high. Moreover, since the concentration of the PCB oil contained in the condenser 22 is reduced by the cleaning solvent 13, the volatilization of the PCB can be prevented. As a result, it is not necessary to drain the PCB oil before the cutting step as in the conventional case.

Further, since the first fragment 23 of the metal case 22a and the second cut piece 24 of the element 22b are separated in the sorting step, the low-concentration PCB detoxification treatment contained in the first fragment 23 of the metal case 22a is performed. , The high-concentration PCB detoxification treatment contained in the second cut piece 24 of the element 22b can be performed separately. Therefore, the metal case 22a can be recycled and the PCB contained in the element 22b can be chemically treated to reliably detoxify the element 22b. Further, since the metal case 22a is provided with a separating step of separating the first fragment 23 and the second cutting piece 24 of the element 22b, the metal case is cut after positioning the upper portion of the capacitor 22 as in the conventional case. It is not necessary to take out the element 22b from the 22a. As a result, a large number of capacitors 22 can be cut at the same time in the cutting process, and the work efficiency is extremely high. Moreover, in the present embodiment, since the method is not to put the entire capacitor 22 into the plasma melting furnace to make it harmless, the aluminum contained in the capacitor 22 becomes aluminum oxide and has a high melting point, which lowers the efficiency of plasma processing. It can be detoxified at low cost without any inconvenience.

Further, in the sorting step, if the first fragment 23 of the metal case 22a and the second cut piece 24 of the element 22b are separated by the difference in specific gravity, the sorting step is extremely easy. The same applies to the above-mentioned metal separation and centrifugal filtration. Further, since the cleaning step of immersing the first fragment 23 and the second cutting piece 24 in the cleaning solvent 13 used in the cutting step to clean the metal case 22a and the element 22b is provided before the chemical treatment step. The processing cost can be reduced as compared with the case where the element 22b is primarily cleaned with another cleaning solvent. Since the cleaning solvent 13 is distilled and reused as the cleaning solvent 13 having a low PCB concentration, it is not necessary to add a new cleaning solvent, and the processing cost can be further reduced.

[Other Embodiments]
(1) Even if the filler 25 contained in the ballast 2 is roughly removed, the filler 25 may adhere to the surface of the capacitor 22. Therefore, the capacitor 22 may be cut with a heated hydrocarbon-based cleaning solvent 13 and the first fragment 23 or the second cutting piece 24 may be immersed in the cleaning solvent 13 for cleaning. As a result, since the cold capacitor 22 is brought into contact with the heated cleaning solvent 13, the filler 25 thermally expands due to a sudden temperature difference and is easily peeled off. As a result, the cleaning efficiency can be further improved.
(2) When reusing the cleaning solvent 13, the distillation apparatus 3 may be provided with a filtration unit to include a filtration step for filtering the abrasive contained in the cleaning solvent 13.
(3) The secondary cleaning in the above-described embodiment may be omitted, or may be performed a plurality of times.

The present invention can be used as a PCB processing method for detoxifying a capacitor.

2 Ballast 13 Cleaning solvent 22 Capacitor 22a Metal case 22b Element 23 First piece 24 Second piece

Claims (4)

A PCB processing method for detoxifying a capacitor having a metal case and an element housed in a ballast.
A cutting step of cutting the capacitor by injecting a cleaning solvent that dilutes the PCB oil contained in the capacitor onto the surface of the capacitor.
A separation step of separating a plurality of cut pieces of the capacitor cut by the cutting step into a first fragment of the metal case and a second cut piece of the element.
A PCB treatment method comprising a chemical treatment step of chemically treating the PCB contained in the second cut piece to make it harmless. The PCB treatment method according to claim 1, wherein the separation step separates the first fragment and the second cut piece by specific gravity separation, metal separation, or centrifugal filtration. The invention according to claim 1 or 2, further comprising a cleaning step of immersing the second cutting piece in the cleaning solvent used in the cutting step to clean the second cutting piece before the chemical treatment step. PCB processing method. The PCB treatment method according to claim 3, wherein the cleaning step is a method of distilling and reusing the cleaning solvent.

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