JP6967856B2 - How to dispose of electrical and electronic component waste - Google Patents

Description

The present invention relates to a method for treating electrical and electronic component waste, and more particularly to a method for treating electrical and electronic component waste suitable for recycling used electronic and electrical equipment.

In recent years, the recycling of electrical and electronic component scraps has been actively carried out. The purpose of electrical and electronic component scraps is to recover the metals in the component scraps, and the products containing electrical and electronic components are incinerated and crushed, or crushed as they are, and the sorting process is combined to combine the metals and resin (plastic). Sort into categories. The separated metals are collected for each different type of metal.

In the recycling of electrical and electronic component scraps, how to efficiently recover the desired metal from the electrical and electronic component scraps with a high recovery rate has been devised. According to Japanese Patent No. 5775752 (Patent Document 1), metals such as tungsten can be recovered by subjecting home appliances to crushing, sieving, magnetic force sorting, eddy current sorting, color sorting, separation sorting, and the like. Have been described.

In Japanese Patent Application Laid-Open No. 2015-123418 (Patent Document 2), electrical and electronic component scraps are crushed, airflow separation is performed, and crushed products having a predetermined size or smaller are self-dissolved without particularly distinguishing between metal scraps and resin scraps. It is described that it is put into a copper smelting furnace such as a furnace for processing.

Japanese Patent No. 5775752 JP-A-2015-123418.

However, the conventional treatment method emphasizes the recovery of metal from the electric / electronic component waste, and has not paid much attention to the separation of the resin waste contained in the electric / electronic component waste.

That is, the resin scraps are derived from the resin scraps in which the copper wiring remains on the resin substrate (hereinafter, also referred to as "board scraps"), the resin scraps having no copper wiring on the resin substrate, the housing of the parts, and the like. Although there are resin scraps (hereinafter, also referred to as “plastic scraps”), it is difficult to sort these substrate scraps and plastic scraps because they have similar physical properties such as specific gravity.

For example, in Patent Document 1, a mounting substrate is recovered by performing each of a magnetic force sorting step, an eddy current sorting step, and a color sorting step on electrical and electronic component scraps containing resins and metals, and the metal in the mounting board is collected. Although it is stated that the resin waste is collected, the resin waste is not sorted.

In Patent Document 2, the resin scraps are charged into a copper smelting furnace such as a flash smelting furnace for processing without being separated in advance, but the resin scraps are charged into a copper smelting furnace to generate an excessive amount of heat. In some cases. This makes it difficult to control the copper smelting furnace, which may hinder operations.

Further, among the resin scraps, there are also resin scraps containing Sb, which is a flame-retardant material. If a large amount of such resin waste enters the copper smelting furnace, the amount of Sb in the copper smelting increases, and the desired metal may not be efficiently recovered. There is also a need to bring as much resin as possible that does not contribute to the recovery of metal into the copper smelting furnace.

In view of the above problems, the present invention can efficiently separate and recover resin scraps, particularly substrate scraps and plastic scraps from electrical and electronic component scraps, and can take out resins that do not contribute to metal recovery to the outside of the metal recovery process. Provided is a possible method for treating electrical and electronic component waste.

As a result of diligent studies to solve the above problems, the present inventor has found that substrate scraps and plastic scraps having similar physical properties can be efficiently separated and recovered by electrostatic sorting.

The present invention completed on the basis of the above findings includes, on one aspect, a resin substrate containing no metal by electrostatically sorting a substrate waste containing at least a flat resin substrate and a material to be treated containing plastic waste. A method for treating electrical and electronic component scraps for separating plastic scraps and substrate scraps including a resin substrate containing metal is provided.

In one embodiment, the method for treating electrical and electronic component scraps according to the present invention is a lightweight material obtained by wind-sorting electrical and electronic component scraps.

In another embodiment, the method for treating electrical and electronic component scraps according to the present invention includes removing wire scraps contained in the object to be treated before electrostatic sorting.

In still another embodiment of the method for treating electrical and electronic component waste according to the present invention, the object to be treated is crushed before electrostatic sorting.

In still another embodiment, the method for treating electrical and electronic component scraps according to the present invention further repeats electrostatic sorting with respect to the sorted material containing the substrate scraps separated by electrostatic sorting.

In still another embodiment of the method for treating electrical and electronic component scraps according to the present invention, the content of plastic scraps in the object to be treated is 15 to 90%.

In still another embodiment, the method for treating electrical and electronic component waste according to the present invention comprises an applied voltage required for electrostatic sorting, a distance and angle between the corona electrode and the electrostatic electrode from the ground electrode, a rotation speed of the ground electrode, and the like. Adjust at least one of the divider angles.

In still another embodiment of the method for treating electrical and electronic component scraps according to the present invention, the substrate scraps separated by electrostatic sorting are incinerated and treated in a copper smelting furnace.

In still another embodiment, the method for treating electrical and electronic component waste according to the present invention includes a flash smelting furnace, a converter, and a TSL furnace.

According to the present invention, resin waste, particularly substrate waste and plastic waste, can be efficiently separated and recovered from electrical and electronic component scraps, and resin that does not contribute to metal recovery can be taken out of the metal recovery processing system. A method for treating electronic component waste can be provided.

It is a schematic diagram which shows the outline of the electrostatic sorter which can be used for the electric electronic component waste processing method which concerns on embodiment of this invention. FIG. 2 shows the relationship between the plastic removal rate and the applied voltage in the electrostatic sorting process in Example 1. It is a flow chart which shows the outline of the processing flow of Example 2.

The method for treating electrical and electronic component scraps according to an embodiment of the present invention mainly separates and recovers resin scraps from electrical and electronic component scraps. Here, the "resin scraps" are (1) "board scraps" in which metal such as copper wiring is attached to the resin in the resin substrate, and (2) scraps containing substantially no metal, that is, copper wiring and the like. It is classified as "plastic waste" containing resin derived from the resin substrate to which the metal does not adhere and the housing of the component.

Since the "board waste" has a metal such as copper wiring, it is a resin waste that can be processed in the metal recovery step described later. On the other hand, among the "plastic scraps", the resin substrate may contain a flame-retardant material such as Sb as described above, and therefore, it is a resin scrap that is desired to be avoided as much as possible from being brought into the metal recovery process.

However, since these substrate scraps and plastic scraps have similar specific densities, it is difficult to sort them by specific densities. It is difficult to efficiently separate these by magnetic force sorting, eddy current sorting, and the like.

The treatment method according to the present embodiment includes electrostatically sorting an object to be treated containing at least substrate waste and plastic waste. As a result, substrate scraps and plastic scraps having similar physical properties can be efficiently and easily separated and recovered. Hereinafter, a specific processing method of the processing method according to the embodiment of the present invention will be described in detail.

(Processing object)
The "electrical and electronic component scraps" in the present invention refer to scraps obtained by crushing electronic and electrical equipment such as waste home appliances, PCs and mobile phones, and after being collected, crushed to an appropriate size. .. In the present invention, the crushing for making electrical and electronic component waste may be performed by the processor himself, or may be crushed in the market and purchased.

The crushing method is not limited to a specific device, but does not include devices belonging to the crusher category. Further, as much as possible, crushing that does not impair the shape of the component is desired, and for example, a substrate surface peeling device, a cross flow shredder, a vertical rotary crusher, or the like is used. A coarse crusher such as a parts separator may be used.

It is desirable that the electric / electronic parts such as wire scraps, capacitors, heat sinks, ICs, and connectors are separated from the resin substrate in the form of a single body in advance by the above-mentioned crushing method. Further, it is desirable that the resin substrate from which the electrical and electronic components are separated is crushed to a certain size.

For example, the electrical and electronic component scraps are preferably crushed to a maximum diameter of about 100 mm or less. However, if the maximum diameter is too small, the raw material may fly up to the corona electrode and the electrostatic electrode, making recovery difficult. Although not limited to the following, it is preferable to use a material having a maximum diameter of about 0.1 mm or more as a processing target.

(Processing flow)
A. Specific density sorting (wind sorting)
First, as a pretreatment, the electrical and electronic component scraps are sorted by using the difference in specific density or by using wind power. A known specific gravity sorting may be performed using a specific gravity sorting machine or the like, but by performing wind power sorting under predetermined conditions, the resin waste contained in the electrical and electronic component waste is efficiently concentrated on the lightweight material side, and at the same time, the resin waste is concentrated on the lightweight material side. Aluminum scraps, iron scraps containing Ni, SUS scraps, etc. can be concentrated toward heavy objects.

The air volume in the wind power sorting step is preferably 3 to 20 m / s, more preferably 8 to 17 m / s, and even more preferably about 10 m / s. According to the experiments by the present inventors, by wind-sorting with the above air volume, 90% or more (weight-based) of the total raw material (electrical and electronic component waste) can be sorted from the substrate waste, and 40 plastic waste can be sorted from the total raw material. % Or more (weight standard) Can be sorted to the lightweight side.

In addition to substrate scraps and plastic scraps, the lightweight material side also includes wire scraps whose surface is covered with an insulator or the like, wire scraps whose conductors are exposed, capacitors, ICs, and the like. The heavy object side contains parts scraps such as ICs and connectors, aluminum scraps, iron scraps containing Ni, SUS scraps, wire scraps, glass and the like.

B. Electrostatic sorting A lightweight material obtained by the above wind power sorting step is used as an object to be processed, and electrostatic sorting is performed on this object to be processed.

The electrostatic sorting is a sorting process for separating a non-conductor and a conductor by using the static electricity generated by the corona discharge, and can be performed by using an electrostatic sorter as shown in FIG. 1, for example. In the electrostatic sorter, the plastic debris in the object to be processed is polarized inside by the static electric field generated between the rotating drum-shaped ground electrode 2 and the electrostatic electrode 4, and is attracted to the ground electrode 2. Then, it is blown off by the brush 5 and recovered by the non-conductor recovery section 7a below the ground electrode 2 (separated matter A).

On the other hand, the substrate scrap containing a part of the conductor such as copper wiring is recovered by the conductor material recovery unit 7b away from the ground electrode 2 due to the repulsive force against the ground electrode 2 and the suction force by the electrostatic electrode 4 (separated material). B). The corona electrode 3 is used to promote the charge due to the polarization of the plastic waste. A divider 6 is arranged between the non-conductor material recovery unit 7a and the conductor material recovery unit 7b, and its angle (γ) is changed according to the trajectory when the substrate waste and the plastic waste fall.

Here, the higher the applied voltage required for electrostatic sorting, the better the separation characteristics between the substrate scraps and the plastic scraps, but if it is too high, arc discharge may occur from the electrostatic electrode 4 and the separation characteristics may deteriorate. be. Further, the distance of the corona electrode from the center of the ground electrode (11), the distance of the electrostatic electrode from the center of the ground electrode (12), the horizontal distance from the center of the ground electrode to the divider (13), and By adjusting the distance in the vertical direction (14), the angle of the corona electrode 3 (α) seen in the counterclockwise direction from the horizontal plane passing through the center of the ground electrode 2, and the angle (β) of the electrostatic electrode, the substrate scraps can be removed. The separation characteristics of plastic waste can be improved.

Therefore, in the present embodiment, it is preferable to adjust at least one of the applied voltage required for electrostatic sorting, the distance and angle of the corona electrode and the electrostatic electrode from the ground electrode, the number of rotations of the ground electrode, and the angle of the divider. ..

In the electrostatic sorting according to the present embodiment, the separation efficiency differs depending on the shape and size of the plastic waste of the object to be treated, but the content of the plastic waste in the whole is 15 to 90% on a weight basis. If it is the plastic waste inside, it can be sorted well.

The object to be treated to be electrostatically sorted may contain wire debris, particularly wire debris in which the conductor is exposed. If a large amount of this wire dust is contained, an arc discharge may occur when the applied voltage of the electrostatic sorter is increased, which may deteriorate the separation efficiency of the substrate waste and the plastic waste. Therefore, it is preferable to remove the debris contained in the object to be treated by, for example, picking, before electrostatic sorting. As a result, the applied voltage of the electrostatic sorter is increased, and the debris collected by the conductor material collecting unit 7b such as the substrate debris can be easily blown away from the ground electrode 2, so that the separation efficiency between the substrate debris and the plastic debris is improved. improves.

The object to be treated may contain plastic debris having a large uneven shape or a rounded shape. According to the experiments by the present inventors, by increasing the applied voltage of the electrostatic sorter, if it is a flat plate, it is possible to recover plastic scraps of a certain size, but for example, L-shaped or V-shaped. When three-dimensional thick plastic scraps such as a mold and a concave mold are contained, the plastic scraps having such a shape cannot secure a sufficient grounding area with the grounding electrode, so that the conductors are moved to the conductor recovery unit 7b side. It may be separated.

Therefore, it is preferable that the object to be processed is crushed to form the shape of the object to be processed before electrostatic sorting so as to be as flat as possible. By performing the crushing process for shape forming, the separation efficiency between the substrate waste and the plastic waste is improved. The size of the plastic waste is not particularly limited, but the crushing treatment may be performed so as to reduce the size of the plastic waste.

For the sorted material containing the substrate waste sorted on the conductor material recovery unit 7b side, the substrate dust and wire dust mixed in the sorted material containing the substrate waste are further removed by picking or the like, and then the above-mentioned static electricity is further performed. By further repeating the electric sorting, the recovery rate of plastic waste (hereinafter, also referred to as "plastic recovery rate") can be improved.

The object to be treated also contains a material showing a good conductor as compared with wire scraps and substrate scraps such as IC. In the electrostatic sorter of FIG. 1, it is also possible to provide three or more recovery sections by further providing a good conductor recovery section (not shown) next to the conductor recovery section 7b.

C. Incinerator treatment It is preferable to incinerate the substrate scraps separated by electrostatic sorting and treat them in a melting furnace such as a copper smelting furnace. In particular, among copper smelting furnaces, it is preferable to process in a converter, a recycling type furnace (TSL) furnace, a self-melting furnace or the like.

According to the method for treating electrical and electronic component scraps according to the embodiment of the present invention, resin scraps, particularly plastic scraps and substrate scraps can be efficiently separated from the electrical and electronic component scraps by a simple treatment. Among the resin scraps, particularly plastic scraps are sorted by electrostatic sorting and taken out of the system of the treatment process, so that the efficiency of recovering metals such as copper in the copper smelting furnace at the subsequent stage can be improved.

Examples of the present invention are shown below together with comparative examples, but these examples are provided for a better understanding of the present invention and its advantages, and are not intended to limit the invention.

(Example 1) Electrostatic sorting conditions Electrostatics A to D, which are lightweight materials obtained by treating with a wind power sorter at an air volume of 10 m / s and have different plastic contents, are shown in FIG. Electrostatic sorting was performed using a sorter. As the electrostatic sorter, an electrostatic high tension separator, EST1014, manufactured by Nippon Elise Magnetics Co., Ltd. was used. The ground electrode drum size (mm): φ255 × 355 W, the corona electrode (mm): φ2 × 406 W, the electrostatic electrode size (mm): 62 × 111 × 406 W, and the ground electrode drum rotation speed: 20 rpm. Corona electrode angle α = 90 degrees, corona electrode distance (11) = 50 mm from the center of the ground electrode, electrostatic electrode angle β = 60 ° C, electrostatic electrode distance from the ground electrode center (12) ) = 100 mm, the angle of the divider 6 was adjusted to γ = 90 degrees, and the applied voltage was changed between 20 and 40 kV. The measurement results are shown in Table 1, and the relationship between the plastic removal rate and the applied voltage is shown in FIG.

In Table 1, "plastic removal rate (%)" indicates the ratio of the weight of the plastic waste selected on the non-conductor material recovery unit side to the total weight of the plastic waste contained in the objects to be treated 1 to 4. "Plastic content (%)" indicates the ratio of the total weight of the plastic waste to the total weight of the parts including the capacitor, the wire waste, etc. in addition to the plastic waste and the substrate waste contained in the objects to be processed 1 to 4. According to Example 1, about 10% to about 80% of the plastic waste contained in the objects to be treated 1 to 4 can be removed from the objects to be treated 1 to 4 having a plastic content (average value) of about 17 to 80%. You can see that.

Further, as shown in FIG. 2, when the objects to be processed 1 to 4 are used, the plastic removal rate (removal rate of plastic waste) can be improved by setting the applied voltage to about 30 to 35 kV. Recognize.

The object 4 to be processed contains more wire debris and conductive component debris than the other objects 1 to 3 to be processed, and an arc discharge is generated by increasing the applied voltage to 40 kV. Therefore, the applied voltage is 40 kV. It could not be evaluated. Since the object 1 to be treated also contained a large amount of wire chips, the plastic removal rate was about 16 to 40%. The object 2 to be treated contained a large amount of plastic waste having a maximum diameter of 50 mm or more, but since most of the objects had a flat plate shape, the plastic recovery rate was higher than that of the objects 1 and 4. The object to be treated 3 had a large amount of flat-plate-shaped debris as a whole, and the size of the debris was about 10 mm on average, which was smaller than that of other objects to be treated, so that the removal rate of plastic debris was high.

(Embodiment 2) Effect of Repeated Electrostatic Sorting According to the processing flow shown in FIG. 3, electrostatic sorting (electrostatic separation) was performed on objects 1 to 4 to be treated, which are lightweight materials obtained by wind sorting at 10 m / s. ) Was repeated twice. By measuring the total weight of the plastic scraps in each of the selected products A, D, and E in FIG. 3, the plastic removal rate after the treatment according to Example 1 and Example 2 was evaluated. The results are shown in Table 2. The electrostatic sorter and conditions are the same as in Example 1 except that the applied voltage is 30 kV.

For each of the objects to be treated 1 to 4, the recovery rate was increased by further electrostatically separating the sorted material transferred to the conductor object side. In particular, it can be seen that the objects to be processed 1 and 3 are increased by 19 to 43%.

(Example 3) Effect of shape of plastic scraps Shape of plastic scraps for (D) non-conductor side sorting material and (E) conductor material side sorting material after the second electrostatic sorting in Example 2. Was evaluated. Most of the plastic scraps sorted on the non-conductor side by electrostatic sorting were plate-shaped with small irregularities. Most of the plastic scraps selected on the conductor side had a plate shape with large irregularities, a rounded rod shape, and a three-dimensional shape. It can be seen that the difference in the contact area with the ground electrode due to the shape of the plastic waste affects the separation efficiency of the plastic waste.

(Example 4) Effect of size of plastic waste Regarding the (D) non-conductor side sorted product and (E) conductor material side sorted product in FIG. 3 obtained in Example 2, less than 9.5 mm, 9 Sort by size using a test sieve of 1.5 mm or more and less than 19.0 mm, 19.0 mm or more and less than 31.5 mm, 31.5 mm or more and less than 37.5 mm, and 37.5 mm or more and less than 50.0 mm. The distribution rates (%) were compared. The results are shown in Table 3.

As shown in Table 3, (D) the distribution ratio of the selected material on the non-conductor side varied greatly depending on the particle size, and no constant tendency was observed. It is considered that the size of the plastic waste itself has a small effect on the separation performance of the plastic waste.

(Example 5) Effect of wire chips (condition 1) and 11 wt% of wire chips (without coating) are 0 wt% (condition 1) and 11 wt% of the non-conductor side sorted products (D) of the objects to be treated 1 to 4 collected in Example 2. (Condition 2), 20 wt% (Condition 3), and 30 wt% (Condition 4) were mixed, and then electrostatic sorting was performed to evaluate the effect on the recovery rate. The conditions of the electrostatic sorter were the same as in Example 2, and each condition was repeated 3 times. The results are shown in Table 4.

The plastic removal rate (%) was 84% on average without the debris content (Condition 1), whereas it was 59 to 93% with the debris content (Conditions 2 to 4). In addition, the larger the mixing ratio of the debris, the larger the standard deviation of the removal rate and the larger the variation.

(Example 6) Effect of capacitor As in Example 5, the capacitor was 0 wt% (condition 1) and 11 wt with respect to the non-conductor side sorted product (D) of the objects to be processed 1 to 4 recovered in Example 2. % (Condition 2), 20 wt% (Condition 3), and 30 wt% (Condition 4) were mixed and then electrostatically sorted to evaluate the effect on the recovery rate. The conditions of the electrostatic sorter were the same as in Example 2, and each condition was repeated 3 times. The results are shown in Table 5.

The plastic removal rate (%) was 85% on average without the capacitor (Condition 1), whereas it was 79 to 84% on average with the capacitor (Conditions 2 to 4). Regarding the standard deviation of the removal rate, it was found that the capacitor was small with respect to the debris.

(Example 7) Effect of substrate waste As in Example 5, the substrate waste is 0 wt% (condition 1) with respect to the non-conductor side sorted product (D) of the objects to be processed 1 to 4 recovered in Example 2. , 11 wt% (Condition 2), 20 wt% (Condition 3), and 30 wt% (Condition 4) were mixed and then electrostatically sorted to evaluate the effect on the recovery rate. The conditions of the electrostatic sorter were the same as in Example 2, and each condition was repeated 3 times. The results are shown in Table 6.

The plastic removal rate (%) was 75% on average when the substrate waste was not contained (Condition 1), whereas it was 76 to 78% on average when the substrate waste was contained (Conditions 2 to 4).

Claims (9)

By electrostatically sorting a substrate waste containing at least a flat plate-shaped resin substrate and a material to be processed containing plastic waste, the plastic waste containing a resin substrate containing no metal and the substrate waste containing a resin substrate containing metal are separated. death,
A method for treating electrical and electronic component waste , which comprises performing a crushing treatment for forming the shape of the object to be processed so that the object to be processed has a flat plate shape before the electrostatic sorting. The method for treating electrical and electronic component scraps according to claim 1, wherein the object to be treated is a lightweight material obtained by wind-sorting electrical and electronic component scraps. The method for treating electrical and electronic component scraps according to claim 1 or 2, wherein the conductor contained in the object to be treated removes bare wire dust before the electrostatic sorting. The method for treating electrical and electronic component scraps according to any one of claims 1 to 3 , wherein electrostatic sorting is further repeated for the sorted material containing the substrate scraps separated by the electrostatic sorting. The method for treating electrical and electronic component scraps according to any one of claims 1 to 4 , wherein the content of the plastic scraps in the object to be treated is 15 to 90%. Claims 1 to 1, characterized in that at least one of the applied voltage required for the electrostatic sorting, the distance and angle of the corona electrode and the electrostatic electrode from the ground electrode, the number of rotations of the ground electrode, and the angle of the divider is adjusted. 5. The method for treating electrical and electronic component waste according to any one of 5. The method for treating electrical and electronic component scraps according to any one of claims 1 to 6 , wherein the substrate scraps separated by electrostatic sorting are incinerated and treated in a copper smelting furnace. The method for treating electrical and electronic component waste according to claim 7 , wherein the copper smelting furnace includes a flash smelting furnace, a converter, and a TSL furnace. The method for treating electrical and electronic component waste according to any one of claims 1 to 7 , wherein the applied voltage for electrostatic sorting is 30 kV or more and less than 40 kV.

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