JP2018149477A - Separation method of covered electric wire - Google Patents

Abstract

PROBLEM TO BE SOLVED: To separate a covered electric wire into a conductor and a covering resin material in a simple process, and to use the separated electric conductor and the covering resin material as a high-purity recycled material. Provide a separation method. SOLUTION: A suspension step of stirring a treatment liquid that separates into an oil phase and an aqueous phase in a stationary state to form an emulsion of the oil phase and the aqueous phase, and a vinyl chloride resin and a plasticizer in the emulsion. Swelling and peeling in which a covered electric wire obtained by coating a conductor with a resin coating material contained therein is dipped to swell the resin coating material, and the swollen resin coating material is peeled from the conductor by stirring the emulsion. It is characterized by comprising at least a step and a recovery step of recovering the conductor and the resin coating material from the treatment liquid, wherein dichloromethane is used as an oil phase of the treatment liquid. [Selection diagram] Figure 1

Description

  The present invention relates to a method for separating a covered electric wire, in which a coated electric wire made of a resin coating material containing a conductor, a vinyl chloride resin and a plasticizer is separated into a resin coating material and a conductor.

A so-called covered electric wire, in which a linear conductor (hereinafter referred to as a conductive wire) is covered with an insulating resin coating material such as vinyl chloride resin, is used in various types of electrical equipment such as automobile electrical components, home appliances, communication equipment, and computers. Widely used as a basic component of equipment. Waste covered electric wires generated in connection with the disposal of such various electric devices mainly contain a lot of useful metals such as copper as conductive wires, and are collected for recycling purposes and recycled as metal materials.
However, since the covered electric wire is covered with the resin coating material around the conductive wire, it is necessary to separate the conductive wire and the resin coating material in recycling.

Conventionally, as a method for separating a covered electric wire into a conductive wire and a resin coating material, for example, in Patent Document 1, the coated electric wire is finely sheared into a chip shape by a shearing machine, and the resin coating material is peeled from the conductive wire. Thereafter, the conductive wire and the resin coating material are separated by specific gravity difference separation using water.
In Patent Document 2, the coated electric wire is heated to carbonize the resin coating material, and then the carbonized resin coating material is removed from the conductive wire, thereby easily peeling the resin coating material from the conductive wire.
In patent document 3, it is made easy to draw | extract a conductive wire from a resin coating material in a post process by immersing a covered electric wire in an organic solvent, and swelling a resin coating material.

JP 2012-089358 A Japanese Patent No. 5134719 Japanese Patent Laid-Open No. 06-279614

  However, the method disclosed in Patent Document 1 is a structure in which the resin coating material is physically peeled off from the conductive wire when the coated electric wire is sheared, so that a small piece of the resin coating material remains on the separated conductive wire. There has been a problem that the purity of the conductor to be recovered is lowered. In addition, in order to accurately separate the resin coating material from the conductive wire, it is necessary to make the screen mesh of the crusher finer, which causes a problem that the processing efficiency is poor because the grinding time becomes extremely long. .

  The method disclosed in Patent Document 2 has a problem that the carbide of the resin coating material adheres to the conductive wire, and the purity of the conductor to be collected decreases. Moreover, since corrosive hydrogen chloride gas is generated by the thermal decomposition of the vinyl chloride resin contained in the resin coating material, there is a problem that the reactor and piping are easily deteriorated and the treatment of the exhaust gas becomes complicated. In addition, since the resin coating material is separated as a carbide, there is a problem that the resin coating material cannot be recycled as a material resource.

  The method disclosed in Patent Document 3 includes a resin coating material swelling step, a conductive wire separation step, a step of dissolving the separated resin coating material in a solvent, and a plurality of separation steps. There is a problem that it is necessary and processing efficiency is poor. Moreover, since the plasticizer contained in the resin coating material is eluted in the solvent, there is a problem that the frequency of regeneration or replacement of the solvent increases.

  The present invention has been made in view of the above-described circumstances, and is capable of separating a covered electric wire into a conductor and a covering resin material by a simple process, and also separating the conductor and the covering resin material after separation. An object of the present invention is to provide a method for separating a covered electric wire that can be used as a high-purity recycled material.

  In order to solve the above problems, the method for separating a coated electric wire according to the present invention is a suspension that stirs a treatment liquid that separates into an oil phase and an aqueous phase in a stationary state to form an emulsion of the oil phase and the aqueous phase. A step of immersing a coated wire formed by coating a conductor with a resin coating material containing a vinyl chloride resin and a plasticizer in the emulsion to swell the resin coating material, and by stirring the emulsion, A swelling and peeling step of peeling the resin coating material swollen from the conductor, and a recovery step of recovering the conductor and the resin coating material from the treatment liquid, and the oil phase of the treatment liquid includes , Dichloromethane is used.

  According to the method for separating a coated wire of the present invention, an oil phase composed of dichloromethane and an aqueous phase composed of water are suspended to form an emulsion of the treatment liquid, and the coated wire is immersed in this emulsion. When the emulsion and the resin coating material come into contact with each other, the resin coating material covering the conductor swells. Since swelling causes a gap between the resin coating material and the conductor, the resin coating material can be easily separated from the conductor by stirring the emulsion. Accordingly, the coated electric wire can be easily and efficiently separated into the conductor and the resin coating material without applying physical stress such as peeling off the resin coating material from the conductor.

  In addition, by using an emulsion of an oil phase and an aqueous phase, the resin coating material swells and peels away from the conductor while the majority of the plasticizer remains in the resin coating material due to the suppression of plasticizer elution by the dispersion of water. can do. Accordingly, for example, dichloromethane can be repeatedly used as the oil phase of the treatment liquid without a time-consuming process such as redistillation, and the recycling cost of the covered electric wire can be reduced.

  In addition, since the vinyl chloride resin constituting the resin coating material is hardly dissolved even when swollen by an emulsion composed of dichloromethane and water, in addition to the reuse of the metal material by collecting the conductor, the resin coating material is also used as the resin material. It becomes possible to reuse as it is, and it is possible to increase the recycling efficiency by reusing the entire covered electric wire without waste.

  In addition, the present invention is a step subsequent to the recovery step, wherein the resin coating is applied from the conductor to an unpeeled covered electric wire in which the resin coating material is not peeled from the conductor by the swelling peeling step. It further comprises a separation step for mechanically peeling the material.

  Moreover, the present invention is characterized in that, in the swelling and peeling step, the concentration of dichloromethane contained in the emulsion is 8.3 vol% or more and 9.1 vol% or less.

  Further, according to the present invention, in the swelling and peeling step, the peeling rate of the resin coating material with respect to the conductor is 95% by mass or more, and the leaching rate of the plasticizer with respect to the oil phase is 5% by mass or less. It is characterized by that.

  In addition, the present invention is a step subsequent to the recovery step, wherein the resin coating is applied from the conductor to an unpeeled covered electric wire in which the resin coating material is not peeled from the conductor by the swelling peeling step. It further comprises a separation step for mechanically peeling the material.

  Further, the present invention is characterized in that, in the swelling and peeling step, the concentration of dichloromethane contained in the emulsion is 5.7% by volume or more and 10.0% by volume or less.

  Further, in the present invention, at the time of completion of the separation step, the peeling rate of the resin coating material with respect to the conductor is 95% by mass or more, and the leaching rate of the plasticizer with respect to the oil phase is 5% by mass or less. It is characterized by being.

  Further, the present invention is characterized in that the mechanical peeling in the separation step separates the resin coating material and the conductor from a non-peeled covered electric wire by stirring in water or shearing.

  According to the method for separating a covered electric wire of the present invention, the covered electric wire can be separated into a conductor and a coated resin material by a simple process, and the separated conductor and the coated resin material can be used as a high-purity recycled material. It becomes possible to provide a method of separating a covered electric wire that can be used.

It is the flowchart which showed the separation method of the covered electric wire which concerns on 1st Embodiment of this invention in steps. It is the schematic diagram which showed the separation method of the covered electric wire which concerns on 1st Embodiment of this invention in steps. It is the flowchart which showed the separation method of the covered electric wire which concerns on 2nd Embodiment of this invention in steps. It is the schematic diagram which showed the separation method of the covered electric wire which concerns on 2nd Embodiment of this invention in steps.

  Hereinafter, the method for separating a covered electric wire according to the present invention will be described with reference to the drawings. The following embodiments are specifically described for better understanding of the gist of the invention, and do not limit the present invention unless otherwise specified. In addition, in the drawings used in the following description, in order to make the features of the present invention easier to understand, there is a case where a main part is shown in an enlarged manner for convenience, and the dimensional ratio of each component is the same as the actual one. Not necessarily.

(First embodiment)
FIG. 1 is a flowchart showing stepwise the method of separating a covered electric wire according to the first embodiment of the present invention. Moreover, FIG. 2 is the schematic diagram which showed the separation method of the covered electric wire which concerns on 1st Embodiment of this invention in steps.
When processing a covered electric wire by the method for separating a covered electric wire according to the present invention, as shown in FIG. The treatment liquid 11 uses a separated liquid treatment liquid that is separated into two phases of an oil phase 11A and an aqueous phase 11B in a stationary state.

The oil phase 11A as the lower phase of the treatment liquid 11 is composed of dichloromethane (methylene chloride: CH ₂ Cl ₂ , specific gravity 1.326). The dichloromethane used as the oil phase 11A may have a purity of 99.9%, for example, and preferably contains a trace amount of alcohol, amine, olefin and the like as a stabilizer against oxidation. On the other hand, the water phase 11B as the upper phase is made of water.

  The oil phase 11A is not miscible with the water constituting the water phase 11B, and dichloromethane is selected from the viewpoint of swelling the vinyl chloride resin contained in the resin coating material of the covered electric wire.

  Next, as shown in FIG. 2B, the treatment liquid 11 is stirred to form an emulsion 11C of an oil phase 11A and an aqueous phase 11B, that is, a suspension of water and dichloromethane (suspension step S2). . In forming the emulsion 11C, for example, various stirring methods such as stirring the processing liquid 11 divided into two phases by rotating a stirring bar or a stirring blade or stirring by ultrasonic vibration can be used. In this embodiment, in order to promote the peeling of the resin coating material from the conductor of the covered electric wire, a stirring method using a vortex is used.

  The concentration of dichloromethane contained in the emulsion 11C obtained in the suspension step S2 is set to 8.3% by volume or more and 9.1% by volume or less. That is, in the treatment liquid preparation step S1, the blending ratio of dichloromethane and water may be determined so that the concentration of dichloromethane is in the range of 8.3% by volume to 9.1% by volume when the emulsion 11C is formed. .

  Next, as shown in FIG. 2 (c), the covered electric wire 21 is put into the thus formed emulsion 11C of dichloromethane and water. The covered electric wire 21 includes, for example, a copper wire (conductor) 22 that is a conductor made of copper, and a tube-shaped resin coating material 23 that covers the copper wire 22. The resin coating material 23 contains a vinyl chloride resin and a plasticizer. The vinyl chloride resin referred to here is a vinyl chloride polymer (polyvinyl chloride: PVC), and the degree of polymerization is about 800-1500. Moreover, a plasticizer is contained in order to ensure flexibility as a covered electric wire, and for example, phthalic acid, adipic acid, phosphoric acid, trimellitic acid, and the like are used. Representative examples of the plasticizer include di (2-ethylhexyl) phthalate (DEHP) and diisononyl phthalate (DINP).

  Regarding the form of the coated electric wire 21, various forms of the coated electric wire 21 can be introduced, for example, those cut into a length of about 1 cm, or those having a length of 1 m, etc. 3 cm is preferred. In the present embodiment, in order to easily separate the copper wire 22 and the resin coating material 23, the covered electric wire 21 that has been shredded to a length of about 1 cm in advance is used.

  Then, the resin covered material 23 of the covered electric wire 21 is swollen by immersing the covered electric wire 21 in the emulsion 11C for a predetermined time or more, and the resin covered material swollen as shown in FIG. 2 (d) by stirring the emulsion 11C. 23 is peeled from the copper wire 22 (swelling peeling process S3).

  In the swelling and peeling step S3, the vinyl chloride resin constituting the resin coating material 23 comes into contact with the dichloromethane dispersed in the emulsion 11C, so that the dichloromethane molecules are taken in between the polymer chains of the vinyl chloride resin and swell. Thereby, the volume after swelling of the resin coating material 23 swells to, for example, about 5 times the volume before swelling. By the swelling, a gap is generated between the resin coating material 23 and the copper wire 22. In addition, the resin coating | covering material 23 maintains a chemical bond after swelling, and a cylindrical shape is maintained.

  And by the stirring for maintaining the emulsion 11C, the resin coating material 23 is peeled from the copper wire 22 while maintaining the tubular shape (the copper wire 22 is detached from the swollen resin coating material 23). The immersion and stirring time of the coated electric wire 21 in the emulsion 11C is preferably 40 minutes to 80 minutes.

  Moreover, in this swelling peeling process S3, since the water is disperse | distributed to the emulsion 11C of the process liquid 11, it suppresses that the plasticizer contained in the resin coating material 23 elutes to a dichloromethane. For example, the elution rate of the plasticizer into dichloromethane constituting the oil phase 11A is 5% by mass or less. By setting the elution rate of the plasticizer to 5% by mass or less as a target value, the reuse efficiency of dichloromethane can be increased, and the cost for the treatment liquid 11 can be reduced.

  In the swelling and peeling step S3 as described above, the peeling rate at which the resin coating material 23 is peeled from the copper wire 22 after a predetermined peeling time, for example, 60 minutes, is set to 95% by mass or more, for example. As a target value, by setting the peeling rate to 95% by mass or more, for example, almost all the resin coating material 23 is peeled from the copper wire 22, and the resin coating material 23 and the copper wire 22 in the subsequent process are separated. Separation work becomes unnecessary.

  When the resin coating material 23 is sufficiently peeled from the copper wire 22, as shown in FIG. 2 (e), the emulsion 11C is allowed to stand and again separated into two phases of an oil phase 11A and an aqueous phase 11B. If the separability is poor, it may be promptly separated by centrifugation. At this time, if the unseparated covered electric wire 21 is stirred only by the aqueous phase 11B and separated, the elution amount of the plasticizer into the dichloromethane is reduced compared with the case where the stirring time is increased by the emulsion 11C. Recycling efficiency can be improved.

  And the resin coating material 23 and the copper wire 22 which were isolate | separated are collect | recovered from the process liquid 11 used as this 2 phase (collection process S4). In the recovery step S4, the resin coating material 23 and the copper wire 22 can be recovered from the treatment liquid 11 by a general solid-liquid separation method such as filtration.

Thereafter, the treatment liquid 11 used in the method for separating a coated electric wire according to the present invention adds dichloromethane, which is a component of the oil phase 11A, taken into the resin coating material 23 that has been peeled off due to swelling of the resin coating material 23 or the like. For example, when the emulsion 11C is formed, the concentration of dichloromethane is in the range of 8.3 vol% or more and 9.1 vol% or less. Can be used repeatedly.
In addition, the dichloromethane taken in by swelling of the resin coating material 23 can be removed from the resin coating material 23 by drying, for example, and the removed dichloromethane can be reused as the oil phase 11A of the treatment liquid 11.

  On the other hand, the separated resin coating material 23 and the copper wire 22 are individually collected by, for example, a method using a sieve, a method using a specific gravity difference, a method using an eddy current, etc., respectively, and recycled vinyl chloride resin material, It can be used as a recycled metal material (copper material).

  As described above, according to the method for separating a coated wire of the present invention, an oil phase 11A made of dichloromethane and an aqueous phase 11B made of water are suspended to form an emulsion 11C of the treatment liquid 11, and this emulsion 11C When the covered electric wire 21 is immersed in the resin coating material 23, the resin coating material 23 covering the copper wire 22 swells, and a gap is generated between the resin coating material 23 and the copper wire 22. Then, the swollen resin coating material 23 can be easily peeled from the copper wire 22 by stirring the emulsion 11C. Thereby, the coated electric wire 21 can be easily and efficiently separated into the copper wire 22 and the resin coating material 23 without applying physical stress such as peeling off the resin coating material from the copper wire.

  Further, when the resin coating material 23 is swelled, the plasticizer contained in the resin coating material 23 is an oil phase by using the emulsion 11C in which the treatment liquid 11 is suspended to suppress the elution of the plasticizer due to the dispersion of water. Almost no elution occurs in dichloromethane constituting 11A. Accordingly, for example, dichloromethane can be repeatedly used as the oil phase 11A of the treatment liquid 11 without a time-consuming process such as redistillation, and the recycling cost of the covered electric wire 21 can be reduced.

  Further, since the vinyl chloride resin constituting the resin coating material 23 hardly dissolves even when swollen with an emulsion composed of dichloromethane and water, in addition to the reuse of the metal material by collecting the copper wire 22, the resin coating material 23 is also used. The resin material (recycled vinyl chloride resin) can be reused as it is, and the entire covered electric wire 21 can be reused without waste to increase the recycling efficiency.

(Second Embodiment)
FIG. 3 is a flowchart showing stepwise a method of separating a covered electric wire according to the second embodiment of the present invention. Moreover, FIG. 4 is the schematic diagram which showed the separation method of the covered electric wire which concerns on 2nd Embodiment of this invention in steps.
In addition, the same number is attached | subjected to the structure similar to 1st Embodiment, and the detailed description is abbreviate | omitted.
In the method for separating a covered electric wire according to the second embodiment, first, as shown in FIG. 4A, a treatment liquid 31 is created (treatment liquid creation step S11). The treatment liquid 31 uses a separated liquid treatment liquid that is separated into two phases of an oil phase 31A and an aqueous phase 31B in a stationary state.

The oil phase 31A that is the lower phase of the treatment liquid 31 is made of dichloromethane (methylene chloride: CH ₂ Cl ₂ ). The dichloromethane used as the oil phase 31A may have a purity of 90%, and more preferably 99% or more. On the other hand, the water phase 31B as the upper phase is made of water.

  Next, as shown in FIG. 4B, the treatment liquid 31 is stirred to form an emulsion 31C of an oil phase 31A and an aqueous phase 31B, that is, a suspension of water and dichloromethane (suspension step S12). ). The concentration of dichloromethane contained in the emulsion 31C obtained in the suspension step S12 is 5.7% by volume or more and 10.0% by volume or less. That is, in the treatment liquid preparation step S11, the blending ratio of dichloromethane and water may be determined so that the concentration of dichloromethane is in the range of 5.7% by volume or more and 10.0% by volume or less when the emulsion 31C is formed. .

  Next, as shown in FIG. 4C, the covered electric wire 21 to be recycled is put into the emulsion 31C of dichloromethane and water thus formed. Then, by immersing the coated electric wire 21 in the emulsion 31C for a predetermined time or longer, the resin coating material 23 of the coated electric wire 21 is swollen, and the resin coating material 23 swollen by the stirring of the emulsion 31C is removed from the copper wire (conductor) 22. It is made to peel (swelling peeling process S13).

  In the swelling and peeling step S13, the vinyl chloride resin constituting the resin coating material 23 comes into contact with dichloromethane dispersed in the emulsion 31C, so that the dichloromethane molecules enter the inside of the vinyl chloride resin and swell the vinyl chloride resin.

  Due to the swelling of the resin coating material 23, a gap is generated between the resin coating material 23 and the copper wire 22. And by the stirring for maintaining the emulsion 31C, the resin coating material 23 is peeled from the copper wire 22 while maintaining the tubular shape. The immersion and stirring time of the coated electric wire 21 in the emulsion 31C is preferably, for example, 40 minutes to 80 minutes.

  Moreover, in this swelling peeling process S13, since water is disperse | distributed to the emulsion 31C of the process liquid 31, the elution to the dichloromethane of the plasticizer contained in the resin coating material 23 is suppressed. For example, the elution rate of the plasticizer into dichloromethane constituting the oil phase 31A is 5% by mass or less.

  As shown in FIG. 4 (e), when the resin coating material 23 peels from the copper wire 22 to some extent, the emulsion 31C is allowed to stand and again separated into two phases, an oil phase 31A and an aqueous phase 31B. Then, the separated resin coating material 23, the copper wire 22, and a small amount of the unseparated covered electric wire 21 are collected from the treatment liquid 11 that has become two phases (collection step S14). In the recovery step S14, the resin coating material 23, the copper wire 22, and a small amount of unseparated covered electric wire 21 can be recovered from the treatment liquid 31 by a general solid-liquid separation method such as filtration.

  Next, as shown in FIG. 4F, the resin coating material 23 is mechanically peeled from the copper wire 22 to the unseparated covered electric wire 21 collected from the treatment liquid 31 (separation step S15). Examples of the method for mechanically peeling the resin coating material 23 from the copper wire 22 include agitation in water using a stirrer and a stirring blade, and separation by shearing using a cutter mill and a shredder. Moreover, you may return the unseparated covered electric wire 21 collect | recovered from the process liquid 31 to a swelling peeling process again.

  In such a separation step S15, even in the case of the unseparated coated electric wire 21, the resin coating material 23 is swollen by contact with the emulsion 31C, so that a gap is formed between the resin coating material 23 and the copper wire (conductor) 22. Therefore, the resin coating material 23 can be easily peeled off from the copper wire 22 with a considerably smaller stress than in the case where the copper wire and the resin coating material are separated from a normal coated electric wire. When the separation step S15 is completed, the peeling rate of the resin coating material 23 with respect to the copper wire (conductor) 22 is 95% by mass or more.

Thereafter, the treatment liquid 31 used in the method for separating a coated electric wire according to the present invention adds dichloromethane, which is a component of the oil phase 31A, taken into the resin coating material 23 that has been peeled off due to swelling of the resin coating material 23 or the like. For example, when the emulsion 31C is formed, the concentration of dichloromethane is in the range of 5.7% by volume or more and 10.0% by volume or less so that the blending ratio of dichloromethane and water is maintained, so that the coated wires are separated. Can be used repeatedly.
The dichloromethane taken into the resin coating material 23 can be removed from the resin coating material 23 by, for example, drying, and can be reused as the oil phase 31A of the treatment liquid 31 by collecting the dichloromethane from the resin coating material 23. It is.

  On the other hand, the separated resin coating material 23 and the copper wire 22 are individually collected by, for example, a method using a sieve, a method using a specific gravity difference, a method using an eddy current, etc., respectively, and recycled vinyl chloride resin material, It can be used as a recycled metal material (copper material).

  As mentioned above, although embodiment of this invention was described, these embodiment is shown as an example and is not intending limiting the range of invention. These embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the spirit of the invention. These embodiments and their modifications are included in the scope and gist of the invention, and are also included in the invention described in the claims and the equivalents thereof.

Hereinafter, the effect of the present invention was verified.
As a covered electric wire, a coated electric wire (mass 10.7 g / m) having a multi-core (30 wires, strand diameter 0.18 mm) having an outer diameter of 1.1 mm and a conductor diameter of 0.6 mm was prepared. The conductor of this covered electric wire is made of a stranded wire made of copper (99.9%). Moreover, as an insulating resin coating material covering this copper wire, a material containing 17.5% by mass of diisononyl phthalate as a plasticizer in a vinyl chloride resin was prepared. The covered electric wire was cut into a length of about 1 cm in advance.

  As the treatment liquid, a liquid composed of an oil phase and an aqueous phase was used. As the oil phase, dichloromethane (DCM), 1,2-dichloroethane, 1,1,2-trichloroethane, trichloromethane (chloroform), trichloroethylene, acetone, ethyl acetate (ethyl acetate), cyclohexane, 1,4-dioxane, respectively. Prepared. Moreover, ion-exchanged water was used as the aqueous phase.

  A treatment liquid in which an oil phase and an aqueous phase were mixed at a predetermined ratio was placed in a round bottom flask, and then a covered electric wire and a magnetic stirrer were added and stirred for a predetermined time. The stirring speed was controlled by a magnetic stirrer. Thereafter, the solid-liquid separation was performed by filtration, and the peel rate after the swelling peel process was calculated by examining the number of unstripped wires relative to the number of charged wires. In Examples 1 to 6 and Comparative Example 2, the unpeeled wire after the swelling and peeling step was put into a round bottom flask containing only ion-exchanged water, and further stirred with a porcelain stirrer for 60 minutes. Thereafter, solid-liquid separation was performed by filtration, and the number of unseparated wires relative to the number of inserted wires was examined to calculate the separation rate after the separation step (the sum of the swelling separation step and the separation rate in the separation step).

Table 1 shows the structures of the treatment liquids of the present invention and the comparative example. In addition, the item (comparative example 3) whose solvent kind in Table 1 is Water shows the process liquid which consists only of an aqueous phase as a comparative example. In the swelling and peeling step, the peeling rate was 0% by mass. Moreover, the item (Comparative Examples 1, 9, 12, and 18) having a solvent concentration of 100.0% indicates a treatment liquid consisting only of an oil phase as a comparative example. Although the peeling rate in the swelling peeling process was as high as 100% by mass, the plasticizer leaching rate was also a high value of 50% by mass or more.
The agitation time indicates the actual time in which the shredded coated electric wire was added and agitated after forming the emulsion of each treatment liquid (excluding Comparative Example 3). The temperature indicates the retention temperature of the emulsion when the coated electric wire is charged and stirring, and is in the range of 18 to 23 ° C.

  In the verification example as described above, the plasticizer leaching rate (% by mass), the peeling rate (% by mass) after completion of the swelling and peeling step, and the peeling at the time of completion of the separation step for mechanically peeling the resin coating material from the copper wire The rate (% by mass) is shown in Table 1.

  From this result, it can be seen that dichloromethane is the only solvent that satisfies the peeling rate of 95% by mass or more and the plasticizer leaching rate of 5% by mass or less. Further, by using dichloromethane as the oil phase and setting the concentration of dichloromethane contained in the emulsion to 8.3 vol% or more and 9.1 vol% or less, the leaching rate of the plasticizer contained in the resin coating material to dichloromethane is 5 It was confirmed that the peeling rate of the resin coating material with respect to the copper wire could be 95% by mass or more while being suppressed to not more than mass%.

  Further, even if the concentration of dichloromethane contained in the emulsion is 5.7% by volume or more and 10.0% by volume or less, by performing the separation step after completion of the recovery step, the plasticizer contained in the resin coating material is converted to dichloromethane. It was confirmed that the peeling rate of the resin coating material with respect to the copper wire could be 95% by mass or more while the leaching rate of the resin was suppressed to 5% by mass or less. When the concentration of dichloromethane contained in the emulsion is 8.3% by volume or more and 9.1% by volume or less (Examples 2 and 3), the leaching rate is 5% by mass or less and the peeling rate in the swelling peeling process is 95% by mass. As described above, the separation rate after the separation step reached 100% by mass by further carrying out the separation step.

11, 31 Treatment liquid 11A, 31A Oil phase 11B, 31B Water phase 11C, 31C Emulsion 21 Coated wire 22 Copper wire (conductor)
23 Resin coating

Claims (7)

A suspension step of stirring the treatment liquid separated into an oil phase and an aqueous phase in a stationary state to form an emulsion of the oil phase and the aqueous phase;
In the emulsion, a coated electric wire formed by coating a conductor with a resin coating material containing a vinyl chloride resin and a plasticizer is immersed to swell the resin coating material, and from the conductor by stirring the emulsion A swelling and peeling step of peeling the swollen resin coating material;
A recovery step of recovering the conductor and the resin coating material from the treatment liquid,
A method for separating a covered electric wire, wherein dichloromethane is used for an oil phase of the treatment liquid.   The method for separating a coated electric wire according to claim 1, wherein the concentration of dichloromethane contained in the emulsion is 8.3% by volume or more and 9.1% by volume or less in the swelling and peeling step.   In the swelling and peeling step, a peeling rate of the resin coating material with respect to the conductor is 95% by mass or more, and a leaching rate of the plasticizer with respect to the oil phase is 5% by mass or less. Item 3. A method for separating a covered electric wire according to item 1 or 2.   The resin coating material is mechanically peeled from the conductor with respect to the uncovered covered electric wire, which is a subsequent process of the recovery step, and the resin coating material is not peeled from the conductor by the swelling peeling step. The method of separating a covered electric wire according to claim 1, further comprising a separating step.   The method for separating a coated electric wire according to claim 4, wherein the concentration of dichloromethane contained in the emulsion is 5.7% by volume or more and 10.0% by volume or less in the swelling and peeling step.   The separation rate of the resin coating material with respect to the conductor is 95% by mass or more at the time of completion of the separation step, and the leaching rate of the plasticizer with respect to the oil phase is 5% by mass or less. The method for separating a covered electric wire according to claim 4 or 5.   The mechanical peeling in the separation step separates the resin coating material and the conductor from a non-peeled covered electric wire by stirring in water or shearing. The method for separating a covered electric wire according to the description.

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