WO2023228912A1

WO2023228912A1 - Separation method for stainless steel and processing method for electrical/electronic component scraps

Info

Publication number: WO2023228912A1
Application number: PCT/JP2023/019001
Authority: WO
Inventors: 琢真武井; 英俊笹岡; 健太郎田辺
Original assignee: Ｊｘ金属株式会社
Priority date: 2022-05-23
Filing date: 2023-05-22
Publication date: 2023-11-30

Abstract

Provided is: a separation method for stainless steel capable of efficiently separating stainless steel from electrical/electronic component scraps, in particular, crushed scraps obtained by subjecting electrical/electronic component scraps to a crushing processing; and a processing method for electrical/electronic component scraps. The separation method for stainless steel includes: a crushing step S2 for crushing electrical/electronic components; an air flow classification step S3 for classifying the crushed substance obtained in the crushing step by air flow and obtaining, as a heavy substance, excluded stones that include stainless steel; a coarse excluded stone sorting step S4 for sorting and collecting, from the excluded stones, coarse excluded stones having at least a predetermined size; and a first magnetic sorting step S6 for magnetically sorting coarse excluded stones and obtaining, as a magnetized substance, coarse excluded stones that include stainless steel, from the coarse excluded stones.

Description

Method of separating stainless steel and processing of electrical/electronic parts waste

The present invention relates to a method for separating stainless steel and a method for disposing of electrical/electronic component waste.

In recent years, from the perspective of resource conservation, valuable metals have been recovered from discarded home appliances and electrical/electronic parts scraps such as PCs and mobile phones, and efficient methods of recovery are being considered. For example, in Japanese Patent No. 6050222 (Patent Document 1), electrical/electronic component scraps containing copper are crushed into a predetermined size, and the crushed electrical/electronic component scraps are used in a copper smelting furnace (flash furnace). It is stated that it should be processed.

Furthermore, Japanese Patent No. 6228843 (Patent Document 2) describes a process of pulverizing electrical/electronic component scraps containing copper, and classifying the pulverized electrical/electronic component scraps using air classification. A method for recovering fine powder from electrical and electronic component scraps is described. The recovered fine powder of the electrical/electronic parts scraps is introduced into a smelting furnace and processed, and the unrecovered granules are processed in an oxidation smelting furnace (converter).

Patent No. 6050222 Patent No. 6228843

As described in Patent Documents 1 and 2, in order to process electrical/electronic component scraps in a smelting furnace such as a flash furnace, it is necessary to crush the electrical/electronic component scraps in advance. However, the pulverized electrical/electronic component scraps contain organic substances such as resins, and these organic substances such as resins contain components such as carbon components that act as reducing agents in the flash furnace. If these components cannot sufficiently react with the combustion air, problems such as overreduction may occur.

On the other hand, the amount of electrical and electronic component scraps processed has been increasing in recent years. (inhibiting substances) may be introduced into the reactor in larger quantities than before.

For example, in the case of a converter, when the amount of smelting inhibiting substances introduced into the converter increases as the amount of electrical and electronic parts scrap increases, a situation arises in which the impurities cannot be completely separated in the converter, and the electrolytic When manufacturing anodes, impurities may increase. In order to improve this situation, it is desirable to remove smelting inhibiting substances in advance from the electrical/electronic component scraps that are fed into the converter. For example, pulverized waste obtained by pulverizing electrical/electronic component waste contains stainless steel containing nickel (Ni), chromium (Cr), etc., which are substances that inhibit smelting. Therefore, it is preferable to efficiently remove stainless steel from the pulverized waste before introducing the pulverized waste into the furnace.

In view of the above problems, the present disclosure discloses a stainless steel separation method that can efficiently separate stainless steel from electrical/electronic component scraps, particularly pulverized waste obtained by pulverizing electrical/electronic component scraps, and a method for separating stainless steel from electrical/electronic component scraps. Provide a processing method.

In order to solve the above problems, according to one aspect of the present disclosure, a pulverization step of pulverizing electrical/electronic component scraps, a pulverized material obtained in the pulverization step is classified by air flow, and waste stone containing stainless steel as a heavy object is provided. The second step is the airflow classification process to obtain coarse waste stones that are larger than a specified size from the waste stones. A method for separating stainless steel is provided, which includes a first magnetic sorting step to obtain a kimono.

According to another aspect of the present disclosure, in the method for treating electrical/electronic parts scraps including the above method for separating stainless steel, the pulverized material obtained in the air classification step is charged into a smelting furnace for processing. and an oxidation smelting furnace treatment step of charging at least a portion of the non-magnetized material obtained in the first magnetic separation step into an oxidation smelting furnace for treatment. be done.

According to the present disclosure, there is provided a method for separating stainless steel and a method for disposing of electrical/electronic parts that can efficiently separate stainless steel from electrical/electronic parts scraps, particularly pulverized waste obtained by pulverizing electrical/electronic parts scraps. Can be provided.

1 is a flowchart showing an example of a method for separating stainless steel according to an embodiment of the present invention. 1 is a schematic diagram showing a configuration example of a rigid roller mill that can be used in a stainless steel separation method according to an embodiment of the present invention. It is a schematic diagram showing an example of an eddy current sorter. It is a schematic diagram showing an example of an air table.

Embodiments of the present invention will be described below with reference to the drawings. The embodiments shown below exemplify devices and methods for embodying the technical idea of this invention. It is not specific.

(Stainless steel separation method)
As shown in FIG. 1, the method for separating stainless steel according to an embodiment of the present invention includes a crushing step S2 for crushing electrical/electronic component scraps, a crushing product obtained in the crushing step S2 is classified by air flow, and a heavy material is an airflow classification step S3 to obtain waste stones containing stainless steel, a coarse waste stone sorting step S4 to sort and recover coarse waste stones of a predetermined size or more from the waste stones, magnetically sorting coarse waste stones of a predetermined size or more, The step S6 includes a first magnetic separation step S6 for obtaining coarse waste stones containing stainless steel as a magnetized material from coarse waste stones.

Before the crushing step S2, it is preferable to perform an incineration step S1 for incinerating at least a portion, preferably all, of the electrical/electronic component waste. By incinerating the electrical/electronic parts waste in the incineration process S1 before the crushing process S2, at least a part of the organic matter such as resin contained in the electrical/electronic parts waste can be removed by incineration, and at the same time, it is possible to remove The volume of the object can be reduced. In addition, by incinerating at least a portion of the organic matter such as resin contained in electrical and electronic component scraps, over-reduction problems caused by carbon components contained in electrical and electronic component scraps during processing in smelting furnaces, etc. can be avoided. It is possible to suppress damage to the furnace bricks and jacket. Furthermore, the metal contained in the electric/electronic component scraps becomes brittle, making it easier to crush them in the subsequent crushing step S2. Incineration removes volatile components from electrical and electronic component scraps, which also prevents fluorine, chlorine, bromine, etc., which are some of the smelting inhibitors, from entering the smelting furnace.

Although the specific conditions of the incineration step S1 are not particularly limited, for example, the electrical/electronic component waste is incinerated at about 550 to 1000° C. in a rotary kiln, and then cooled. The incinerated material after the incineration treatment may be further sieved, for example, using a sieve with an opening of 10 mm to 20 mm.

In the crushing step S2, electrical/electronic component scraps are crushed using a crusher. In this pulverization process, before the incinerated parts waste settles to the bottom of the settler of a smelting furnace (for example, a flash furnace), or before it is discharged from the mat or slag discharge section, unburned carbon content is oxidized. The Cu component reacts with the S component in the copper concentrate to form matte, and the Fe component reacts with oxygen to crush electrical and electronic component waste to a particle size that can be turned into slag.

Specifically, the particle size of the concentrate charged into the smelting furnace is generally 10 to 150 μm as a volume-based D50 (median diameter). It is preferable to grind until the standard D50 is 150 μm or less. Further, electrical/electronic component scraps may be pulverized until the volume-based D80 becomes 250 μm or less. Here, the powder with a D50 of 150 μm or less and the granule with a D80 of 250 μm or less are fine like powder, and are much finer than a sand-like material with the size of a grain of sand. . It is preferable to obtain a pulverized product by pulverizing the material into fine particles such as powder.

In the crushing step S2, the electrical/electronic component scraps may be mixed with silicate ore charged together with the copper concentrate in a smelting furnace and crushed. Normally, in nonferrous smelting furnaces, a solvent such as silicate ore is charged into the smelting furnace together with the raw material concentrate to improve the fluidity of the slag, but when purchasing the solvent, it is purchased in cheap lump form. In many cases, the powder is ground in-house using a ball mill or the like. Therefore, if there is sufficient capacity in the solvent mill, it is possible to mix electrical and electronic component scraps with silicate ore charged with copper concentrate in a smelting furnace and crush them, without requiring the cost of introducing crushing equipment. It can be implemented.

In the airflow classification step S3, the pulverized material obtained in the pulverization step S2 is divided into light and heavy materials by adjusting the air volume using the airflow classification effect, and the pulverized material of electrical/electronic component scraps is separated into light and heavy materials. Control granularity. That is, in the airflow classification step S3, if the pulverized materials in the electrical/electronic component scraps have a high specific gravity and are not finely pulverized, they cannot be carried upward by the airflow. The finely pulverized material is carried upward by the air current and collected on the light material side, and the pulverized material with a large particle size that cannot be collected on the light material side is separated as waste stone to the heavy material side.

It is preferable that the pulverizing step S2 and the air classification step S3 be performed at the same time using a vertical roller mill as shown in FIG. In processing using a vertical roller mill, first, electrical/electronic component scraps to be pulverized are fed through a screw feeder to the center of a horizontally rotating table. A recessed portion is formed along the outer circumferential side of the table. Electrical/electronic component scraps supplied to the center of the table are moved toward the outer circumference of the table by centrifugal force. At this time, electrical/electronic component waste is crushed between the table and rollers (2 to 3 pieces) attached along the upper surface of the recessed part of the table.

Electrical and electronic component waste that has been crushed into fine powder moves toward the outer periphery, is blown up by an upward airflow (using the atmosphere) that flows from below to above, is classified (airflow classification), and is placed above. It is carried into the rotor and collected. On the other hand, pulverized materials with a high specific gravity fall downward, are crushed again by the rollers and table, are blown up again, are carried into the rotor, and are collected. Around the table, pulverized materials with large particle sizes or specific gravity that have not been classified into lightweight materials remain. The heavy objects remaining around the table are called waste stones. This waste rock contains stainless steel, which constitutes smelting inhibiting substances such as Ni and Cr, in addition to copper and the like. By separating stainless steel from this waste rock, stainless steel can be efficiently recovered and used effectively, and the amount of smelting inhibiting substances introduced into a smelting process such as a converter or flash furnace can be reduced.

Note that the pulverization step S2 and the air classification step S3 may be performed separately using separate devices without using a vertical roller mill. Moreover, before processing the pulverized material with the vertical roller mill, it may be roughly crushed with a hammer crusher or the like.

In the coarse waste stone sorting step S4, coarse waste stones of a predetermined size or larger are sorted from the waste stones obtained in the airflow classification step S3. In the coarse waste stone sorting step S4, the method is not particularly limited as long as it is possible to sort the coarse waste stones for each predetermined particle size, but there is no particular limitation on the method. It is preferable to include a step.

Table 1 shows examples of chemical analysis values of valuable metals contained in waste rock of each size when waste rock is sieved using various sieves with different openings. Component analysis of valuable metals was evaluated using ICP optical emission spectrometry (ICP-OES). Further, the size of each waste stone shown in Table 1 represents the size of the nominal opening W (mm) of the sieve based on JIS Z8801-1. In addition, "%" described as a unit of each element means the weight % of the target element in the waste rock of each size. Since the concentrations of Au and Ag are small, they are evaluated in terms of "g/t (equivalent to ppm)".

As shown in Table 1, it has been newly found that the content of Cr and Ni, which constitute stainless steel, increases as the size of the waste stone increases. In order to efficiently recover stainless steel, a sieve with a nominal opening W of 3.35 mm or more, preferably 5.6 mm or more, and more preferably 9.5 mm or more is used, and the waste stone that has been sorted to the sieve upper material side is used. It is preferable to collect it as coarse waste stone for recovering stainless steel. Here, for example, the size of more than 1.0 mm to 3.35 mm is sorted to the bottom side of the sieve using a sieve with a nominal opening of 3.35 mm, and is sieved using a sieve with a nominal opening of 1.0 mm. This refers to waste stone that has been sorted to the high quality side.

Furthermore, regarding the coarse waste stone that has been sieved according to the predetermined sizes shown in Table 1, grain sizes of more than 5.6 mm to 6.7 mm, grain sizes of more than 6.7 mm to 9.5 mm, and grain sizes of more than 9.5 mm to 16 We focused on the five main metallic elements contained in coarse waste stone with a grain size of more than 16.0 mm, Cu, Fe, Al, SUS, and other metals, and examined the composition ratio of SUS among them. . Analysis of Cu, Fe, Al, SUS, and other metals was performed by hand sorting, and a comprehensive judgment was made based on the magnetism of the raw material, the color, hardness, and weight of the polished surface when the raw material was polished with a file. As a result, the SUS ratio contained in the coarse waste stone with a grain size of more than 5.6 mm to 6.7 mm was 11.4%, and the SUS ratio contained in the coarse waste stone with a grain size of more than 6.7 mm to 9.5 mm was 16. 5%, the SUS ratio contained in the coarse waste stone with a grain size of more than 9.5 mm to 16.0 mm is 17.2%, and the SUS ratio contained in the coarse waste stone with a grain size of more than 16.0 mm is about 27.4%. It was found that the larger the particle size, the higher the proportion of SUS in the composition.

From the above analysis results, it was found that in order to efficiently recover stainless steel from coarse waste stones, it is effective to carry out a process of collecting coarse waste stones that are larger than a predetermined size. Considering the recovery efficiency of stainless steel and the ease of handling of the objects to be sorted when using a sorting device such as a metal sorter, which will be described later, the size of coarse waste stone to efficiently recover stainless steel is determined by the nominal opening W. It is preferable to use a sieve with a diameter of 5.6 mm or more, more preferably 6.7 mm or more, and even more preferably 9.5 mm or more to collect waste rock of a size that can be sorted into sieve material. Although there is no particular upper limit to the size of the crushed stone, it is typically 100 mm or less, and further 50 mm or less.

The sieving step is preferably performed after the air classification step S3. If the pulverized material after the pulverization step S2 is directly sieved without performing the air classification step S3, there is a risk that the finely pulverized material adhering to the surface of the pulverized material having a large particle size will be separated as sieved material. Since the finely pulverized material has a high grade of copper and precious metals, it causes a loss of valuable materials when recovering coarse stone containing stainless steel. After the air classification step S3 is performed on the crushed material after the crushing step S2, coarse waste stones of a predetermined size or more are sorted out in the sieving step, so that the finely crushed materials are separated from the waste stones in the air classification step S3. Since it can be separated and recovered, the amount of pulverized material adhering to waste stone can be minimized.

Next, in the first magnetic sorting step S6, rough waste stones containing stainless steel are obtained as a magnetized material (magnetized material 2) from the coarse waste stones collected in the coarse waste stone sorting step S4. Most of the copper, aluminum, etc. that constitute the coarse waste stone are sorted to the non-magnetic material side (non-magnetic material 2). In order to efficiently obtain coarse waste stone containing stainless steel as a magnetized material, it is preferable to perform high magnetic force sorting with a magnetic flux density of 3000 to 7000 G using, for example, a magnetic pulley in the first magnetic force sorting step. As a result, coarse waste stones containing stainless steel can be selectively and efficiently recovered to the magnetic object side while separating the coarse waste stones containing copper-aluminum etc. to the non-magnetic object side.

In addition, before the first magnetic sorting step S6, the coarse waste stones are magnetically sorted with a lower magnetic force than the first magnetic force sorting step S6, and the coarse waste stones containing iron are preliminarily treated as the magnetic material side (magnetic material 1). It is more preferable to include a second magnetic force sorting step S5 in which the non-magnetic substances 1 are obtained. Iron is easier to magnetize with a lower magnetic force than stainless steel, so by performing processing with a lower magnetic force than in the first magnetic force sorting step S6, almost 100% of the coarse waste stone containing iron can be sorted to the magnetic object side. . For example, in the second magnetic force sorting step, it is preferable to perform low magnetic force sorting with a magnetic flux density of 200 to 600 G using, for example, a hanging magnetic separator. By removing in advance the iron that is magnetically attracted to the magnetic object side in the second magnetic sorting step S5, in the first magnetic sorting step S6, it is possible to prevent coarse waste stones containing iron from being mixed in, and Exhaust stone can be efficiently concentrated on the magnetic object side.

Next, in the eddy current sorting step S7, the magnetic material obtained in the first magnetic sorting step S6 is subjected to eddy current sorting, and coarse waste stone containing stainless steel is obtained as a non-repellent material from the magnetic material obtained in the first magnetic sorting step S6. . In the eddy current sorting step S7, for example, a sorting process using an eddy current sorter shown in FIG. 3 can be performed.

An eddy current sorter, for example, includes a belt conveyor stretched between a tail pulley (not shown) and a head pulley, an eccentric magnet placed inside the head pulley, and a drive device (not shown) that rotates the belt conveyor. ), a non-repulsion object collection section provided below the head pulley to collect non-repulsion objects that have flown up from the belt conveyor, and a repulsion object collection section located below the head pulley and in front of the non-repulsion object recovery section. and a damper that is provided between the non-repulsion object recovery section and the repulsion object recovery section and separates the flying repulsion object from the non-repulsion object. As shown in Figure 3, by using an eccentric type eddy current sorting device in which the rotation axis of the pulley and the rotation axis of the eccentric magnet do not match, it is possible to reduce the entrainment of magnetic materials and to separate coarse waste stone containing stainless steel. It can be done efficiently.

In order to efficiently separate coarse debris containing stainless steel from the magnetized material 2 in the first magnetic separation step S6 to the non-repellent material, the rotation speed of the rotor provided in the eddy current separator is preferably set to 2000 to 2700 rpm, for example. is 2250 to 2500 rpm, and the speed of the belt conveyor is 90 to 110 m/min, preferably 95 to 105 m/min. Further, in order to efficiently separate the coarse waste stone containing stainless steel to the non-repellent side, it is preferable to appropriately adjust the angle of the damper (angle θ in FIG. 3).

For example, the angle of the damper is preferably 55° or more, more preferably 60° or more. On the other hand, if the angle of the damper is too large, there is a risk that coarse debris containing copper, aluminum, etc. will be mixed into the non-repellent side. In this embodiment, the angle of the damper is preferably adjusted to about 50 to 70 degrees, more preferably adjusted to about 55 to 67 degrees, and even more preferably adjusted to about 58 to 65 degrees. For example, by adjusting the angle of the damper to about 58 to 65 degrees, more than 90% of the stainless steel in the coarse waste can be recovered on the non-repellent side.

Next, in the shape sorting step S8, the non-repellent materials obtained in the eddy current sorting step S7 are shape sorted to obtain coarse waste stone containing stainless steel as a heavy product. In the example of FIG. 1, an example is shown in which the shape sorting step S8 is provided after the eddy current sorting step S7, but for example, the eddy current sorting step S7 is omitted and the shape sorting step S8 is The order of the processing may be changed so that the magnetic material is sorted by shape and coarse waste stone containing stainless steel is obtained as a heavy product. As the shape sorter, various kinds of sorters that utilize differences in specific gravity and shape of the objects to be sorted can be used, and the type thereof is not particularly limited. For example, a sorting machine that rolls and sorts raw materials can typically be used, and for example, an air table or the like is preferably used.

The rough waste stone containing stainless steel separated in the first magnetic sorting step S6 often has a plate-like shape. On the other hand, other coarse waste stones containing copper, aluminum, etc. are often close to spherical in shape. Therefore, in the shape sorting step S8, by using shape sorting that utilizes the specific gravity difference and shape difference of the objects to be sorted, it is possible to more efficiently collect coarse waste stone containing plate-shaped stainless steel.

As the shape sorter, a single-axis air table sorter can be used. For example, but not limited to, an air table sorter as shown in FIG. 4 can be used. The air table sorter is installed to separate light products and heavy products by dry specific gravity sorting, and is inclined at a predetermined angle and has a plurality of small vent holes (not shown) for passing air. a vibration table that vibrates in the direction of the vibration table; a holding part (not shown) that holds the vibration table; a blower blower (not shown) that is provided below the holding part and supplies air from the bottom surface of the vibration table to the top surface; It is equipped with a hopper (not shown) for feeding raw materials into the vibrating table.

The plate-shaped coarse waste stone containing stainless steel supplied onto the vibrating table receives a force that moves it toward the heavy product side due to the vibration of the vibrating table. On the other hand, light objects or spherical objects are strongly affected by the slope and are recovered on the light product side.

In the shape sorting step S8, in order to more efficiently collect the coarse waste stone containing stainless steel, it is preferable that the inclination angle of the vibration table is 10 degrees or less with respect to the horizontal plane, and is 9 degrees or less. It is more preferable to incline the angle at an angle of 8° or less. If the angle of inclination is too small, the separation efficiency between light products and heavy products may not be improved. Therefore, the inclination angle of the vibrating table is preferably 5 degrees or more, more preferably 6 degrees or more, and even more preferably 7 degrees or more. In this embodiment, for example, by adjusting the inclination angle of the vibrating table to 6 to 10 degrees, 85% or more of the stainless steel, and in one embodiment, 92% or more of the stainless steel, is transferred to the heavy product side with respect to the coarse waste stone containing stainless steel. This allows efficient separation and recovery of stainless steel. Note that the frequency at which the vibration table vibrates can be adjusted as appropriate. Typically, the frequency is adjusted between 50 and 60 Hz, more preferably between 55 and 60 Hz. Furthermore, air may be supplied from a blow-up blower if necessary.

Next, in the metal sorting process S9, the heavy products obtained in the shape sorting process S8 are metal-sorted using a metal sorter including a sensor capable of detecting the strength of the metal reaction, and are separated from coarse waste stones containing copper and brass to those containing stainless steel. Separate and collect the coarse waste stone. By providing the metal sorting step S9, the concentration of stainless steel in the separated and recovered material can be increased, and the stainless steel recovery efficiency can be further increased.

The metal sorter used in the metal sorting step S9 requires sensing technology that can selectively detect stainless steel from mixed metals including stainless steel, copper, brass, etc. For example, metal sorters can sense transmitted X-rays (XRT), fluorescent X-rays (XRF), laser-excited plasma (LIBS), near-infrared (NIR), visible light (VIS), electromagnetic induction (ISS), Raman spectroscopy, etc. One example is a metal sorter that uses technology.

Among these, in order to efficiently separate and recover coarse waste stones containing stainless steel from the electrical/electronic component scraps according to this embodiment, it is preferable to use a metal sorter using electromagnetic induction (ISS) type sensing technology. In metal sorters that use electromagnetic induction (ISS) type sensing technology, there are two types of metal reaction detection methods: one that detects the presence or absence of metal, and the other that detects the strength of the metal reaction. . In the present embodiment, in order to efficiently separate and sort waste stones containing stainless steel, it is more preferable to use a metal sorter that utilizes a detection method that detects the strength of a metal reaction. Thereby, the stainless steel in the coarse waste stone can be efficiently separated and recovered.

Although not limited to the following, the metal sorter includes a pair of pulleys that hold a belt conveyor, a metal object recovery section and a non-metal object recovery section provided below the belt conveyor, and a belt conveyor. A detection section is placed on the bottom surface of the belt conveyor and detects the metal reaction of raw materials by generating electromagnetic waves from a predetermined area on the bottom surface of the belt conveyor. It is possible to include a sorting device such as an air nozzle for distributing the objects to the object recovery section.

In metal sorters that use electromagnetic induction (ISS) type sensing technology, if the particle size of the raw materials supplied to the metal sorter is too small, the sorting section will not be able to efficiently sort the raw materials, which may reduce recovery efficiency. be. Therefore, it is preferable that the particle size of the coarse waste stone supplied to the metal sorter is set so that it has a particle size that is equal to or larger than the lower limit of the particle size that can be sorted by the metal sorter. For example, in the above-mentioned coarse stone sorting step S4, by determining the size of the coarse stone in advance so that it has a particle size equal to or larger than the lower limit of the particle size that can be sorted by a metal sorter, it is possible to The metal sorting efficiency in the sorting step S9 can be improved. The specific lower limit of the particle size of coarse ore that can be sorted by a metal sorter is not particularly limited, but is, for example, about 5 mm, more preferably a particle size of 8.0 mm or more, and even more preferably a particle size of 10.0 mm. It is 0 mm or more.

Table 2 shows the SUS recovery rate (weight ratio) and concentration ratio when coarse waste stones with various particle sizes are sorted using a metal sorter that uses ISS type sensing technology that detects the strength of metal reactions. represent. The size of each coarse stone shown in Table 2 corresponds to the nominal opening W (mm) of the sieve based on JIS Z8801-01. The concentration ratio shown in Table 2 represents the concentration ratio of SUS contained in the recovered coarse stone after sorting to the weight of SUS contained in the coarse stone before sorting. As shown in Table 2, in the case of coarse waste stone with a particle size of 8.0 mm or more that is sorted to the sieve top side using a sieve with a nominal opening W of more than 8.0 mm, the It can be seen that the SUS ratio is 90% or more in all cases. That is, by sorting coarse waste stones with a grain size of 8.0 mm or more using a metal sorter, it is possible to improve the SUS ratio in the recovered material after the sorting process.

The sieved material separated in the rough waste stone sorting step S4 in FIG. 1, the magnetic material 1 separated in the second magnetic separation step S5, the non-magnetic material 2 separated in the first magnetic separation step S6, and the eddy current Table 3 shows an example of the measurement results of the composition ratio and distribution ratio of the main components in the coarse waste stone contained in the repulsion separated in the sorting step S7 and the heavy products and light products separated in the shape sorting step S8. . At this time, in the coarse waste stone sorting step S4, a sieve with a nominal opening size of 5.6 mm was used. In the second magnetic sorting step S5, a hanging magnetic separator was used to set the magnetic flux density to 400G, and in the first magnetic sorting step S6, a magnetic pulley was used to set the magnetic flux density to 7000G. In the eddy current sorting step S7, the damper angle was 62°, the rotor rotation speed was 2250 rpm, and the belt conveyor speed was 103 m/min. In the shape selection step S8, the inclination angle was 8°, the table frequency was 50 Hz, and the wind speed was 0 mm/s. In Table 3, the composition ratio of stainless steel, copper/brass, iron, and aluminum is analyzed comprehensively based on the magnetism of the raw material, the color, hardness, and weight of the polished surface when the raw material is sanded. The selection was done by hand. The composition ratio (%) means the weight ratio of the target substance in each sorted material. The distribution ratio was calculated by setting each component of the sieve as 100%, and calculating the weight ratio of each component separated as magnetic material 1, non-magnetic material 2, repellent material, light product, and heavy product. As shown in Table 3, it can be seen that more than 70% of the stainless steel in the sieved material can be recovered as a heavy product in the shape sorting step S8. Further, most of the heavy products separated in the shape sorting step S8 are coarse waste stones containing stainless steel and coarse waste stones containing copper or brass. Therefore, by performing metal sorting on heavy products using a metal sorter that uses sensing technology that can selectively detect stainless steel from mixed metals, the concentration of stainless steel in the separated and recovered material can be increased, and stainless steel can be recovered. It can be seen that the efficiency can be further increased.

As described above, according to the stainless steel separation method according to the embodiment of the present invention, waste stones are collected from the crushed waste obtained by pulverizing electrical/electronic parts waste, and the above-mentioned method for separating and recovering stainless steel from the waste stones is performed. By performing this process, it becomes possible to efficiently separate stainless steel. As a result, it is possible to reduce the amount of smelting inhibiting substances such as Ni and Cr derived from stainless steel supplied to the oxidation smelting furnace such as a converter, and prevent processing inhibition due to impurities in the oxidation smelting furnace. The impact can be minimized. Since fine powder etc. have been removed from the separated and recovered coarse waste stone containing stainless steel in the air classification step S3, the influence of recovery loss of valuable metals due to adhesion of fine powder containing valuable metal components can be reduced, and the powder It is easier to handle than the shaped ones. Therefore, according to the stainless steel separation method according to the embodiment of the present invention, stainless steel can be selectively and efficiently separated and recovered while suppressing a decrease in recovery efficiency of valuable metals.

(Method for disposing of electrical/electronic parts waste)
The method for treating electrical/electronic component scraps according to the embodiment of the present invention involves charging the separated materials obtained in each step of the stainless steel separation method shown in FIG. 1 into a smelting furnace such as a flash furnace. It can include a smelting furnace treatment step in which the material is treated in a smelting furnace, and an oxidation smelting furnace treatment step in which the material is charged into an oxidation smelting furnace such as a converter. That is, the method for treating electrical/electronic component scraps according to the embodiment of the present invention includes a smelting furnace treatment step in which the pulverized material obtained in the airflow classification step S3 is charged into a smelting furnace and treated; An oxidation smelting furnace treatment step is included in which at least a portion of the non-magnetized material 2 obtained in the magnetic separation step S6 is charged into an oxidation smelting furnace and treated.

Although the type of smelting furnace does not matter, it is composed of, for example, a shaft (not shown), a settler, and an uptake, and the shaft is equipped with a concentrate burner at its ceiling. From the concentrate burner, the finely pulverized material obtained in the air classification step S3, copper concentrate, a solvent (flux), and oxygen-enriched air are blown simultaneously to cause an oxidation reaction to occur instantaneously. The finely ground material that has undergone the oxidation reaction is separated into matte and slag in a settler. In addition, the exhaust gas generated in the smelting furnace is sent to the uptake. Regarding the operating conditions of the smelting furnace in the smelting furnace treatment process, as long as the overreduction phenomenon does not occur, the smelting furnace should be operated under the same known operating conditions regardless of whether or not electrical/electronic parts scraps are input. The treatment conditions are not particularly limited.

Although the type of oxidation smelting furnace does not matter, for example, a furnace port is provided at the top of a furnace body (not shown), and tuyeres are provided at the lower side of the furnace body. At least a portion of the non-magnetized material 2 obtained in the first magnetic separation step S6, the matte separated in the smelting furnace, and a solvent (flux) are charged into the furnace from the furnace mouth. Further, oxygen-enriched air is blown from the tuyere to oxidize at least a portion of the non-magnetized material 2 obtained in the first magnetic separation step S6. In the operation of the oxidation smelting furnace in the oxidation smelting furnace treatment step, any known operating method may be used in order to operate the oxidation smelting furnace to the extent that the original intended function of the oxidation smelting furnace is not lost.

As shown in FIG. 1, the coarse waste stone separated as magnetic material 1 in the second magnetic separation step S5, the coarse waste stone separated as non-magnetic material 2 in the first magnetic separation step S6, and the eddy current separation step The coarse waste stone separated as a repulsion material in S7, the coarse waste stone separated as a light product in the shape sorting process S8, and the coarse waste stone other than stainless steel separated as a coarse waste stone that does not contain stainless steel in the metal sorting process S9 is preferably charged into an oxidation smelting furnace. In addition, metal sorting is further performed using a metal sorter on the magnetic objects 1 in the second magnetic sorting step S5 and the non-magnetic objects 2 obtained in the first magnetic sorting step S6, and coarse waste stones containing stainless steel are separated into metals. The recovery efficiency of stainless steel may be improved by separating the stainless steel into materials and inputting this separated material into any of the eddy current sorting step S7, shape sorting step S8, and metal sorting step S9.

According to the method for processing electrical/electronic component scraps according to the embodiment of the present invention, stainless steel containing smelting inhibiting substances such as Ni and Cr is removed in advance from the raw material supplied to an oxidation smelting furnace such as a converter. For example, various operational troubles due to the contamination of smelting inhibiting substances in the oxidation smelting furnace treatment process can be suppressed, and efficient processing can be performed. Furthermore, stainless steel can be reused by collecting waste stone containing stainless steel.

Although the present invention has been described using the above embodiments, it is not limited to each embodiment, and the components can be modified and embodied without departing from the gist thereof. Moreover, various inventions can be formed by appropriately combining a plurality of components disclosed in each embodiment. For example, some components may be deleted from all the components shown in the embodiments. Furthermore, components of different embodiments may be combined as appropriate.

Further, the processing flow shown in FIG. 1 is an example, and it goes without saying that various other processing procedures can be adopted. For example, it goes without saying that the eddy current sorting step S7, the shape sorting step S8, and the metal sorting step S9 may be omitted or their order may be changed as appropriate. For example, the eddy current sorting step S7 and the shape sorting step S8 can be omitted. It is also possible to change the order of the eddy current sorting step S7 and the magnetic sorting step (first magnetic sorting step S6 and second magnetic sorting step S5). Further, in the above-described embodiment, an example is explained in which a metal sorter using ISS type sensing technology is used as the metal sorter, but a metal sorter using other sensing technology such as an X-ray sorter or LIBS sorter may also be used. Of course it's a good thing.

S1...Incineration process S2...Crushing process S3...Airflow classification process S4...Rough waste stone sorting process S5...Second magnetic force sorting process S6...First magnetic force sorting process S7...Eddy current sorting process S8...Shape sorting process S9...Metal Sorting process

Claims

A pulverizing process for pulverizing electrical and electronic component scraps;
an airflow classification step in which the pulverized material obtained in the pulverization step is classified with an airflow to obtain waste rock containing stainless steel as a heavy object;
a coarse waste stone sorting step of sorting and recovering coarse waste stones of a predetermined size or more from the waste stones;
A method for separating stainless steel, comprising: a first magnetic sorting step of magnetically sorting the coarse waste stone, and obtaining coarse waste stone containing stainless steel from the coarse waste stone as a magnetic substance.
Before the first magnetic sorting step, a second magnetic force for magnetically sorting the coarse waste stones with a lower magnetic force than in the first magnetic force sorting step and removing coarse waste stones containing iron from the coarse waste stones. A sorting process;
2. The stainless steel separation method according to claim 1, further comprising an eddy current sorting step of eddy current sorting the magnetic material obtained in the first magnetic sorting step to obtain coarse waste stone containing stainless steel as a non-repellent material.
2. The method for separating stainless steel according to claim 1, further comprising a shape sorting step of sorting the shape of the magnetic material obtained in the first magnetic sorting step to obtain coarse waste stone containing stainless steel as a heavy product.
3. The method for separating stainless steel according to claim 2, further comprising a shape sorting step of sorting the shape of the non-repellent material obtained in the eddy current sorting step to obtain coarse waste stone containing stainless steel as a heavy product.
Further, a metal sorting step is carried out in which the heavy products obtained in the shape sorting step are sorted for metal using a metal sorter including a sensor capable of detecting the strength of metal reaction, and coarse waste stones containing stainless steel are sorted and recovered as metal objects. The method for separating stainless steel according to claim 3 or 4.
6. The stainless steel separation method according to claim 5, wherein the coarse waste stone sorting step involves sorting and recovering coarse waste stones having a particle size equal to or larger than the lower limit of the particle size that can be sorted by the metal sorter.
The coarse waste stone sorting step includes a sieving step of sieving the waste stone using a sieve, and in the sieving step, the sieve surface is sieved using a sieve with a nominal opening of 3.35 mm or more. The method for separating stainless steel according to any one of claims 1 to 4, which comprises obtaining the stainless steel as the coarse waste stone.
The stainless steel separation method according to any one of claims 1 to 4, further comprising an incineration step of incinerating the electrical/electronic component waste before the pulverization step.
A method for processing electrical/electronic parts waste, including a method for separating stainless steel according to any one of claims 1 to 4,
a smelting furnace treatment step in which the pulverized material obtained in the airflow classification step is charged into a smelting furnace and treated;
and an oxidation smelting furnace treatment step of charging at least a portion of the non-magnetized material obtained in the first magnetic separation step into an oxidation smelting furnace.