阅读说明：本技术 电子/电气设备部件屑的处理方法 (Method for processing electronic/electric equipment component scraps ) 是由 青木胜志 笹冈英俊 于 2020-03-27 设计创作，主要内容包括：本发明提供一种能够从电子/电气设备部件屑中选择性回收包含回收目标物质的基板屑的电子/电气设备部件屑的处理方法。本发明是一种电子/电气设备部件屑的处理方法,其特征在于,在对电子/电气设备部件屑进行磁力筛选的步骤之前,具有将电子/电气设备部件屑所包含的带导线的基板分离的步骤。(The invention provides a processing method of electronic/electric equipment component scraps, which can selectively recover substrate scraps containing recovery target substances from the electronic/electric equipment component scraps. The present invention is a method for processing electronic/electrical equipment component dust, characterized by comprising a step of separating a substrate with a lead included in the electronic/electrical equipment component dust, prior to a step of magnetically screening the electronic/electrical equipment component dust.)

1. A method for processing electronic/electric equipment part scraps,

the method includes a step of separating the substrate with the lead included in the electronic/electric equipment component dust before the step of magnetically screening the electronic/electric equipment component dust.

2. The method of processing electronic/electric equipment parts scraps according to claim 1,

separating the substrate with lead wire included in the electronic/electric device component dust so that the substrate with lead wire in the processing object supplied to the step of performing magnetic force screening is 10 mass% or less.

3. The method of processing electronic/electric equipment part dust according to claim 1 or 2,

the step of separating the wired substrate contained in the electronic/electric equipment part dust uses wind screening.

4. The method of processing electronic/electric equipment parts scraps according to claim 3,

the wind speed of the wind screening is 10-20% higher than that of plastic separation.

5. The method of processing electronic/electric equipment part dust according to claim 3 or 4,

and (3) crushing the scraps of the electric/electronic equipment components before the wind power screening by using a shear crusher or a hammer crusher.

6. The electronic/electric equipment parts scrap handling method according to any one of claims 1 to 5,

eddy current screening is performed after the magnetic screening.

Technical Field

The present invention relates to a method for processing electronic/electric equipment component dust, and more particularly, to a method for processing electronic/electric equipment component dust suitable for recycling processing of used electronic/electric equipment.

Background

In recent years, from the viewpoint of resource conservation, it has been increasingly prevalent to recover valuable metals from scrap of electronic/electrical equipment parts such as waste household electrical appliances, PCs, and mobile phones, and methods for efficiently recovering such valuable metals have been studied and proposed.

Among valuable metals contained in electronic/electrical equipment component scrap, iron is used for applications such as housings, frames, and component support materials, and a relatively large amount of iron is contained in electronic/electrical equipment component scrap. In addition, since the amount of processing in the subsequent processing steps can be reduced by removing the relatively large amount of iron component contained in the electronic/electric equipment component dust at first, magnetic force screening is often used in the initial stage of screening.

In addition to iron, a large amount of the electronic/electrical equipment part scraps is plastic. Since plastic is effective for weight reduction, a large number of articles made of plastic are used for a housing, and electronic/electrical equipment parts are also contained in a large proportion, particularly in small-sized home appliances. Therefore, it is also effective to remove the plastic first, and it is also known as an effective means to improve the sieving property by adding air sieving prior to the magnetic sieving (for example, see patent documents 1 and 2).

Documents of the prior art

Patent document

Patent document 1: japanese laid-open patent publication No. 2002-059082

Patent document 2: japanese patent laid-open publication No. 2003-320311

Disclosure of Invention

Problems to be solved by the invention

On the other hand, electronic/electrical equipment component dust also contains a large amount of substrate dust. The substrate scrap is formed with a copper foil and a circuit obtained by copper plating, and is an important component scrap as a raw material for the purpose of copper recovery, but the substrate scrap contains various substances such as iron and plastic in addition to copper, and therefore, the substrate scrap is often recovered to an unintended side in recovery by a screening machine, and it is very difficult to selectively recover the substrate scrap containing the recovery target substance.

In view of the above-described problems, the present invention provides a method for processing electronic/electrical equipment component dust, which can selectively collect substrate dust containing a recovery target substance from electronic/electrical equipment component dust.

Means for solving the problems

The present inventors have intensively studied to solve the above problems and found that: among various substrate scraps obtained by roughly crushing electronic/electrical equipment component scraps, a substrate with a lead attached thereto is recovered to the magnetic side by magnetic force screening, and loss of valuable metals contained in the substrate scraps occurs.

One aspect of the present invention, which has been completed based on the above-described findings, is a method for processing electronic/electrical equipment component dust, including a step of separating a substrate with a lead included in the electronic/electrical equipment component dust, prior to a step of magnetically screening the electronic/electrical equipment component dust.

Effects of the invention

According to the present invention, there can be provided a method of processing electronic/electrical equipment component dust capable of selectively recovering substrate dust containing a recovery target substance from electronic/electrical equipment component dust.

Drawings

Fig. 1 is a cross-sectional view showing an example of a wind power screening apparatus suitable for collecting a substrate with a wire according to an embodiment of the present invention.

Fig. 2 is a plan view of the wind power sieving apparatus around the guide portion.

Fig. 3 is a plan view of the guide portion as viewed from the diffusion chamber side.

Fig. 4 is a side view of the wind power sieving apparatus around the guide portion.

Fig. 5 is a side view of the wind power sieving apparatus around the guide portion.

Fig. 6 is a graph showing changes in the distribution ratio of the substrates with leads to the weight side when the wind speed is changed using the wind screening apparatus with the guide portion (with the guide) and the wind screening apparatus without the guide portion (without the guide).

Fig. 7 is a graph showing changes in the distribution ratio of the flat plate-like ICs to the weight side when the wind speed is changed using the wind screening apparatus with the guide portion (with the guide) and the wind screening apparatus without the guide portion (without the guide).

Detailed Description

In the present embodiment, the "electronic/electrical equipment component scrap" is scrap obtained by crushing waste household electrical appliances, electronic/electrical equipment such as PCs and mobile phones, and is scrap which is collected and crushed into an appropriate size. In the present embodiment, the scrap pieces for producing the electronic/electric equipment components may be crushed by the processor itself, but the scrap pieces that have been crushed in the market may be purchased.

As the crushing method, crushing in which the shape of the member is not damaged as much as possible is desirable, and for example, a shear type crusher using a shearing method or a hammer type crusher using an impact method is preferably used. On the other hand, a device belonging to a mill product for the purpose of grinding into finer particles is not included in the crushing process of the present embodiment.

The scrap of electronic/electric equipment parts is preferably crushed to a maximum diameter of 100mm or less, more preferably 50mm or less, and the representative diameter is preferably about 4 to 70mm or about 4 to 50 mm. The "representative diameter" means an average value of 5 times in the case where an arbitrary 100 points are decimated from the electronic/electrical equipment component chips, an average value of major diameters of the decimated electronic/electrical equipment component chips is calculated, and the operation is repeated 5 times.

The electronic/electric equipment component dust is preferably separated individually in the form of substrate dust, wire dust, IC, parts such as connectors, synthetic resin (plastic) used for metal, housings, and the like by coarse crushing in advance. This makes it easier to screen specific individual parts in the subsequent process, and improves the screening efficiency.

In the present embodiment, the term "board dust" refers to a dust obtained by separating (individually separating) a mounted electronic component from a printed wiring board by roughly crushing the printed wiring board (configured such that the electronic component is soldered to the printed wiring board and operated as an electronic circuit) mounted on an electronic/electrical device. The printed wiring board is a board made of an insulator, on which conductors are arranged inside and electronic components are mounted. The substrate scrap is classified mainly into three types by the rough crushing treatment, namely (1) a substrate with a wire and a component, (2) a substrate with a wire, and (3) a substrate without a wire. When the electronic/electric equipment component scrap is subjected to a crushing treatment using a shear crusher, a substrate with a lead and a component and a substrate with a lead are mainly obtained. In the case of performing a crushing process of electronic/electrical equipment part scraps using a hammer crusher, a substrate without a wire is mainly obtained.

Mounted components such as Integrated Circuits (ICs), resistors, capacitors, and transistors are fixed to a printed wiring board, but among them, components fixed by leads may be partially left on the board by the leads and solder when they are separated from the board. In this embodiment, such a substrate including a lead and a component is defined as a "substrate with a lead and a component". The substrate with the lead and the member is a substrate to which a metal member made of iron, aluminum, or the like is attached in addition to the lead, and when the substrate is supplied to the magnetic force screening, it is likely that the metal member is distributed to the magnetic material (Fe dust) side and a loss of valuable metal occurs. Therefore, it is desirable that the substrate with the wires and the components be crushed again to further separate the components attached to the substrate. In addition, a substrate on which the mounted electronic component is not separated from the printed wiring board is included in the "substrate with leads and components", and the "substrate scrap" is a generic term for the "substrate with leads and components", the "substrate with leads", and the "substrate without leads".

A substrate without a conductive line refers to a substrate that does not include a conductive line, a component, and the like. The substrate without a wire can be screened by the same screening process as the synthetic resin used for the case or the like.

The substrate with conductive lines is a substrate including conductive lines. The substrate is a scrap of parts that is difficult to sort out because it contains various substances such as iron and plastic, but the substrate with a wire can be selectively separated and recovered and used as a raw material to be charged into a smelting step, whereby the recovery efficiency of copper can be improved, and this is very useful as a recovery target. However, since the substrate with a lead wire is often formed of iron or the like as in the substrate with a lead wire and a member, the lead wire is distributed to the magnetic material (Fe dust) side and a loss of valuable metal occurs when the lead wire is directly supplied to the magnetic force sorting process.

Therefore, the method for processing electronic/electric equipment component dust according to the present embodiment includes a step of selectively separating and collecting the substrate with the lead included in the electronic/electric equipment component dust, before the step of performing the magnetic force screening. The step of selectively separating and recovering the substrate with the conductive wires may be performed immediately before the magnetic screening step or may be performed earlier than the magnetic screening step. For example, before performing magnetic screening, the present embodiment may include performing the following processes: in any stage of obtaining a processing material by roughly crushing the waste household electrical appliances, electronic/electrical appliances such as PC and mobile phone, which are materials of electronic/electrical appliance component scraps, a wind screening process is performed to separate a substrate with a lead.

The step of separating the substrate with lead included in the electronic/electric device component dust is preferably to separate the substrate with lead so that the substrate with lead included in the processing object supplied to the step of performing magnetic force screening is 10 mass% or less, further 7 mass% or less, further 5 mass% or less, further 1 mass% or less. Thus, even when magnetic force screening is performed thereafter, the contamination of the substrate with the conductive wire to the magnetic substance side can be suppressed, and the valuable metal recovery efficiency in the smelting step can be improved.

As a method for separating and collecting substrates with wires included in electronic/electrical equipment component dust, wind screening and screening using a camera such as a color sensor or a metal sorter are effective. Among them, by using the wind power screening, the substrate with the conductive wire can be separated and recovered efficiently and easily.

In order to more efficiently convey the substrate with the conductive wire included in the electronic/electric device part dust to the light-weight side in the wind sifting, it is generally preferable to increase the wind speed of the wind sifting by about 10 to 20%, and further about 12 to 18%, more than the wind speed of the separable plastic.

However, since a part of the lead and the solder remains on the substrate with the lead, the shape of the substrate with the lead may be difficult to be efficiently sorted into a light-weight object depending on the specific gravity. For example, if the wind speed is too high, other component debris, for example, light-weight materials such as aluminum foil, are mixed, which is not preferable. Therefore, in the present embodiment, it is preferable to individually readjust the conditions for an appropriate wind speed such as removing the substrate with the lead as a light weight after examining the state (shape and size) of aluminum in the electronic/electrical device component scrap.

Specifically, the wind speed is preferably set to 15m/s or more, more preferably 16m/s or more, and still more preferably 16.5m/s or more as the processing condition for wind screening. On the other hand, if the wind speed is too high, the economical efficiency is impaired, and the substrate with the lead wire cannot be efficiently removed in some cases, so the wind speed is preferably 20m/s or less, more preferably 19m/s or less, and further 18m/s or less.

The wind screening may be performed in at least two stages. For example, a combination of a first air-force screening process for separating in advance powder and film-like materials that adversely affect the visibility of a camera of a color screening machine such as a camera or a metal sorting machine used for physical screening and a second air-force screening process for concentrating a plate-like material containing valuable materials on the light-weight side and separating metals such as Fe and Al on the weight side may be used. The first air screening treatment is performed at a wind speed of, for example, 5 to 8m/s, preferably 6 to 7m/s, and the second air screening treatment may be performed under the same conditions as described above.

The first pneumatic screening process may be performed immediately before the screening material is introduced into the screening machine using the function of recognizing the object by the camera, but may be performed in combination with any previous screening step. For example, it may be combined with at least any one of magnetic screening, and color screening processes performed after the pneumatic screening.

The content of the substrate with a conductive wire included in the raw material is also related, but it is preferable that the ratio of the substrate with a conductive wire distributed to the light-weight side by the wind screening is 95% or more, further 97% or more, further 99% or more. By conveying the substrate with a wire, which is distributed to the light-weight side, to the smelting step, valuable metals such as copper contained in the substrate with a wire can be recovered.

Fig. 1 to 5 show an example of an air classifier suitable for the embodiment of the present invention. The air-powered screening machine comprises a diffusion chamber 1, a blower 2 for generating an air flow in the diffusion chamber 1, a supply part 3 for supplying a screening object including a plate-like object 10 including a substrate with a wire into the diffusion chamber 1, a guide part 4 extending from the end of the supply part 3 on the diffusion chamber 1 side into the diffusion chamber 1, a weight recovery part 5 provided below the supply part 3 of the diffusion chamber 1, and a weight recovery part 6 provided below the diffusion chamber 1 on the rear side in the feeding direction of the screening object. A motor 7 of a blower for circulating air inside the diffusion chamber 1 is provided at an upper portion of the diffusion chamber 1.

The air flow indicated by the solid line arrows in fig. 1 is generated in the diffusion chamber 1 by the air blown from the blower 2. In the wind power screening apparatus of fig. 1, a downward air flow is formed in a diagonal direction from the blower 2 toward the heavy material collecting unit 5, an upward air flow is formed from the heavy material collecting unit 5 toward the upper side of the guide unit 4, a lateral air flow is formed above the diffusion chamber 1 in the supply direction from the supply port, and a downward air flow is formed from the upper side of the diffusion chamber 1 toward the light material collecting unit 6.

Further, although the example in which the blower 2 is disposed near the center of the diffusion chamber 1 is illustrated, the position of the blower 2 is not limited to the example illustrated in fig. 1, and may be any that can bring an upward airflow into contact with the object to be screened that is supplied to the guide section 4 and can screen out the heavy object and the light object in the object to be screened by the wind force.

The objects to be screened are supplied from the inlet of the supply section 3, and are supplied to the guide section 4 protruding into the diffusion chamber 1 while being vibrated by the vibration member 3 a. The objects to be screened contact the upward airflow from below the guide 4 at the guide 4. By this airflow, the light-weight material flies upward above the guide section 4, spreads into the diffusion chamber 1, and falls toward the light-weight material collection section 6 located on the rear side in the supply direction. The heavy objects supplied to the guide section 4 with gravity greater than the wind force of the upward airflow fall downward of the guide section 4 and are collected by the heavy object collecting section 5. The dashed arrows in fig. 1 indicate the flow direction of the heavy objects and the light objects, respectively.

As shown in fig. 2, the guide portion 4 has a comb-like shape, and includes a base portion 4a connected to the distal end 3A of the supply portion 3 by welding, screwing, or the like, and a plurality of projections 4b projecting into the diffusion chamber 1 from the base portion 4a connected to the distal end 3A side of the supply portion 3. The projections 4b are formed so as to have a uniform thickness (width) W1 from the end 3A side of the supply portion 3 toward the supply direction X. It is desirable that the plate-like object including the substrate with the wire contact the airflow as much as possible from the time point when the leading end thereof flies out from the distal end 3A side of the supply part 3, and therefore the protrusion is desirably uniform in thickness.

Spaces 4c through which the air flow passing through the guide portion 4 contacts the object to be screened are provided between the projections 4b, and the spaces 4c are formed so that the width W2 of each space 4c is uniform from the end 3A side of the supply portion 3 toward the supply direction X. By having such a shape, the object to be screened can be blown more and can be brought into contact with a more uniform air flow, and therefore, the object can be easily pushed further upward regardless of the type of the light-weight object.

Preferably, as shown in fig. 3, at least the lower surface 41b of the projection 4b has a curved surface. This reduces the air resistance of the guide section 4 against the upward airflow flowing from below the guide section 4, and improves the screening efficiency of the plate-like object 10 including the substrate with a wire according to the present embodiment. In the example shown in fig. 3, the lower surface 41b of the projection 4b has a curved surface, and the upper surface 42b of the projection 4b that is in contact with the object to be screened has a flat surface. By having such a shape, the object to be screened can be smoothly supplied without being caught on the upper surface 42b of the projection 4b, and the contact resistance of the projection 4b to the upward air flow flowing upward from below the projection 4b can be reduced, so that the air flow can be more efficiently brought into contact with the plate-like object 10 including the substrate with a wire of the present embodiment. The projection 4b may have a rod shape having curved surfaces on both the upper surface 42b and the lower surface 41b, for example, in addition to the example shown in fig. 3. The shape of the inverted triangle may be used for smooth supply and efficient contact of the air flow.

The thickness W1 of the projection 4b and the width W2 of the space are preferably set to be smaller than the average diameter D2 of the short diameter of the plate-like object 10 including the substrate with the conductive wire so that the plate-like object 10 including the substrate with the conductive wire as the object to be screened does not fall from the guide 4.

The length L (see fig. 2) of the guide 4 from the distal end 3A side of the supply part 3 to the distal end side of the diffusion chamber 1 is preferably equal to or greater than the average diameter D1 or D2 of the plate-like object 10 including the substrate with a lead wire as the object to be screened, preferably equal to or greater than half the average diameter D1 of the major axis, and more preferably equal to or greater than 2/3. The width W of the guide portion 4 may be set to be the same as the width of the supply portion 3.

By setting the length L of the guide section 4 to be equal to or more than half the average diameter D1 or D2, preferably equal to or more than half the average diameter D1 of the long diameter, of the plate-like object 10 including the substrate with the wire, the upward air flow from below the guide section 4 can be made to sufficiently contact the plate-like object 10 including the substrate with the wire, and therefore the plate-like object 10 including the substrate with the wire can be more reliably made to fly upward of the guide section 4 and spread toward the light-weight object collection section 6 side. If the length L is too long to be necessary, the space 4c may be clogged with a heavy object such as metal that attempts to move toward the heavy side, and therefore, the average diameter D1 of the long diameter of the plate-like object is preferably 2 times or less.

Further, with respect to the average diameters D1 and D2 of the plate-like object 10 including the lead-equipped substrates, arbitrary 10 points of the plate-like object 10 in the objects to be sorted are sampled, and the average diameters of the 10 points sampled on the major and minor diameters of the plate-like object 10 including the lead-equipped substrates are calculated. This operation was repeated 5 times, and an average value of 5 times was shown.

Specifically, the thickness W1 of the projection 4b may be 1 to 10mm, preferably 2 to 5mm, and the width W2 of the space 4c may be 1 to 20mm, preferably 2 to 5 mm. The length L of the guide part 4 may be 25 to 100mm, preferably 40 to 70mm, but is not limited thereto.

As shown in fig. 4, the guide section 4 is disposed such that the air flow flowing upward from below the guide section 4 contacts the lower surface 10A of the plate-like object 10 including the substrate with lead mounted on the protrusion 4b of the guide section 4 in a direction perpendicular to the lower surface 10A of the plate-like object 10.

By arranging the guide section 4 so that the air flow contacts the lower surface 10A of the plate-like object 10 including the substrate with leads in the vertical direction, the upward air flow formed by the air flow can generate a force acting on the plate-like object 10 including the substrate with leads to the maximum, and the air resistance can be adjusted uniformly and maximally along the feeding direction of the guide section 4.

As shown in fig. 5, an adjustment mechanism 4d for adjusting the angle of the guide portion 4 may be provided so that the airflow contacts the lower surface of the plate-like object 10 including the substrate with leads in the vertical direction. Thus, even when the supply unit 3 is inclined, the air flow flowing upward from below the guide unit 4 can be made to vertically contact the lower surface 10A of the plate-like object 10 including the substrate with a lead.

The heavy material collection unit 5 and the light material collection unit 6 may be constituted by a discharge rotor or the like that is generally available, and the specific configuration is not particularly limited. Further, by bringing an air flow having a wind speed of 15m/s or more into contact with the lower surface 10A of the plate-like object 10 including the substrate with leads by the air blown by the blower 2, the plate-like object 10 including the substrate with leads can be wind-screened from the electronic/electric equipment component dust more efficiently.

According to the wind power screening apparatus and the wind power screening method using the same shown in fig. 1, the plate-like object 10 including the substrate with the conductive wire among the electronic/electric device component dust as the screening target object can be efficiently brought into contact with the air flow by providing the guide portion 4. Thus, the plate-like object 10 including the substrate with the lead wire, in which the air resistance greatly changes depending on the direction of the wind, can be more efficiently sorted to the light-weight side (inside the light-weight object collection unit 6).

Fig. 6 and 7 show changes in the distribution ratio of the substrate and the planar IC as the plate-like object including the valuable object to the weight side in both cases of performing the wind screening of the electronic/electric device component debris by changing the wind speed using the wind screening device (with the guide) provided with the guide portion 4 and performing the wind screening of the electronic/electric device component debris by changing the wind speed using the conventional wind screening device (without the guide) not provided with the guide portion 4.

As shown in fig. 6, when the wind screening process is performed at a wind speed of 15m/s or more, the wind screening apparatus without the guide portion 4 can move to the weight side by about 3%, while the wind screening apparatus with the guide portion 4 can greatly reduce the mixing of the plate-like objects moving to the weight side to 3% or less. When the wind screening apparatus of fig. 1 is used, the mixing ratio of the substrate on the weight side can be further reduced to 1% or less by setting the wind speed to 16m/s or more, and can be substantially 0% when 16.7m/s or more is used.

As shown in fig. 7, when wind screening is performed at a wind speed of 15m/s or more, about 9 moves to the weight side in the wind screening apparatus without the guide portion 4, while the contamination of the substrate moving to the weight side can be greatly reduced to 3% or less in the wind screening apparatus with the guide portion 4. When the wind power screening apparatus of fig. 1 is used, the wind speed is set to 15.6m/s or more, whereby the ratio of the plate-like objects including the substrate with the conductive wires mixed into the weight side can be further reduced to 1% or less, and can be substantially 0% when the wind speed is set to 16.1m/s or more.

Since IC is partially made of iron, it may be distributed to the magnetic side in magnetic screening, and thus, when Fe is screened by magnetic screening, IC may be mixed in, and the efficiency of collecting valuable materials may be lowered. By using the wind power screening according to the embodiment of the present invention, since the flat-plate-shaped IC can be removed in advance before the magnetic screening, the reduction in the efficiency of collecting valuable materials in the magnetic screening can be suppressed. In general, since the IC after the crushing process is smaller in maximum diameter than the substrate in many cases, when the wind power sifting apparatus provided with the guide portion 4 of fig. 1 is used to perform the wind power sifting, the IC can be collected to the light weight side in a larger amount, and the mixing into the weight side can be suppressed. According to the test by the present inventors, the mixing ratio of IC into the weight material was 61% when the guide portion 4 was not provided, whereas the mixing ratio of IC into the weight material was significantly reduced to 0.1% or less when the guide portion 4 was provided.

According to the method for processing electronic/electrical equipment component dust of the embodiment of the present invention, before magnetic screening of electronic/electrical equipment component dust, the substrate, particularly the substrate with the lead wire, in the electronic/electrical equipment component dust in which the screening efficiency of the magnetic screening is reduced is removed in advance by the wind screening process, whereby the reduction in the screening efficiency of the magnetic screening due to the mixing of the substrate with the lead wire into Fe dust and Al dust can be suppressed, and the loss of valuable metals can be reduced.

Further, when it is desired to perform eddy current screening after magnetic screening to recover, for example, Al, since the substrate contains copper and has high conductivity, when the crushed particle size is large, the substrate is distributed to the repelling side in the eddy current screening in the same manner as Al. Therefore, in the magnetic screening, the substrate not distributed to the magnetic side but mixed into the non-magnetic side may be distributed to the Al debris in the eddy current screening. In the present embodiment, by performing the wind screening process in advance before the processes of the magnetic screening and the eddy current screening, it is possible to reduce the substrate loss in the magnetic screening as well as the substrate loss in the eddy current screening. Therefore, when a physical screening step of performing eddy current screening is provided after magnetic screening, the effect of reducing valuable metal loss can be more advantageously exhibited by the process of the present embodiment in particular.

The substrate to be distributed to the magnetic material by magnetic force screening is preferably 5% or less, more preferably 3% or less, and still more preferably 1% or less. By reducing the ratio of the substrate distributed to the magnetic material by the magnetic force screening as much as possible, the substrate loss in the case of performing the eddy current screening thereafter can be reduced.

As described above, the present invention is not limited to the present embodiment, and the constituent elements may be modified and embodied without departing from the scope of the invention. In addition, various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the present embodiment. For example, some of the components may be deleted from all the components shown in the present embodiment or the components may be combined as appropriate.

Description of the reference numerals

1 diffusion chamber

2 blower

3 supply part

3A terminal

3a vibrating member

4 guide part

4a base

4b projection

4c space

4d adjusting mechanism

5 weight recovery part

6 light-weight material recovery part

7 exhaust part

10 plate-like objects.