Method for treating objects to be treated including massive copper wire scrap

Abstract

Provided is a treatment method whereby massive objects to be treated that are contained in objects to be treated can be inhibited from remaining. The treatment method, which is for treating objects including rod-shaped objects and massive objects, is characterized in that: oscillating screens including a plurality of screens arranged along a conveyance direction are used to screen the objects while conveying the objects, each screen comprising a platy flat portion and a pectinate portion; the pectinate portion of each screen, except the screen located most downstream in the conveyance direction, overlaps some of the flat portion of the adjoining screen downstream in the conveyance direction and thereby forms a plurality of openings; when the diameter of the openings is expressed by D and the conveyance-direction length of the flat portion is expressed by L1, then the expression 2×D≤L1≤10×D is satisfied; when the gap between the pectinate portion and flat portion of the two screens forming the openings is expressed by H, then the expression 0.2×D≤H≤0.5×D is satisfied; and due to the screening, the massive objects in the objects are collected on the screens.

Description

Method for treating object containing lump copper wire scraps

[0001] The present invention relates to a method for treating an object to be treated that contains lump-shaped copper wire scraps.

[0002] In recent years, from the perspective of resource conservation, recovery of valuable metals from discarded home appliances and scrap parts of electronic and electrical equipment such as PCs and mobile phones has become increasingly popular, and efficient recovery methods have been studied and proposed.

[0003] For example, Japanese Patent Laid-Open Publication No. 9-78151 (Patent Document 1) discloses a method for recycling valuable metals from scrap, in which scrap containing valuable metals is charged into a flash smelting furnace for copper ore smelting from the shaft ceiling and the valuable metals are recovered into matte remaining in the furnace. According to the configuration of Patent Document 1, scrap processing is combined with copper smelting in a copper smelting flash smelting furnace, so valuable metals can be recovered at low cost even from scrap with a low valuable metal content.

[0004] It has also been proposed to reduce the volume of scrap electronic and electrical equipment parts by pulverizing the scrap electronic and electrical equipment parts before processing them in a copper smelting flash furnace. For example, Japanese Patent Laid-Open Publication No. 2015-123418 (Patent Document 2) describes incinerating copper-containing scrap electronic and electrical equipment parts, pulverizing them to a predetermined size or smaller, and processing the pulverized scrap electronic and electrical equipment parts in a copper smelting furnace.

[0005] Furthermore, coated copper wire scrap is known as one type of copper-containing electronic and electrical equipment scrap. Materials with stable shapes and good conditions are used for recycling, while materials with shapes and conditions that are difficult to process are exported overseas as valuable resources. However, in recent years, coated copper wire scrap that is difficult to process has been accumulating in Japan, and there has been a demand for the proposal of a new method for efficiently processing this difficult-to-process coated copper wire scrap and recovering valuable resources.

[0006] Japanese Patent Application Laid-Open Publication No. 2010-236718 (Patent Document 3) discloses a method for operating a gasification melting furnace in which industrial waste is fed into a fluidized bed gasification furnace, and air is blown in from the bottom to form a fluidized bed, thereby gasifying part of the industrial waste by pyrolysis and recovering non-combustible materials containing valuable metals, and the pyrolysis gas produced in the gasification furnace and part of the non-combustible materials transported by the pyrolysis gas are treated in a melting furnace to produce slag, characterized in that calcium-containing dust is made into a slurry and blown into the melting furnace.

[0007] As a facility for melting industrial waste, such as automobile shredder residue (hereinafter also referred to as "ASR") and home appliance shredder residue, which contains metals such as aluminum, iron, copper, zinc, and lead, and vinyl chloride, which serves as a chlorine source, industrial waste melting treatment facilities equipped with fluidized bed gasification furnaces are known, and one example is the melting treatment facility disclosed in Japanese Patent Laid-Open No. 11-302748 (Patent Document 4).

[0008] The fluidized bed gasification furnace disclosed in Patent Document 3 is intended to recover valuable metals contained in the above-mentioned industrial waste.

[0009] Japanese Patent Laid-Open No. 9-78151 Japanese Patent Laid-Open No. 2015-123418 Japanese Patent Laid-Open No. 2010-236718 Japanese Patent Laid-Open No. 11-302748

[0010] In a fluidized-bed gasifier, sand, a granular material used as a heat transfer medium, is introduced through a heat transfer medium inlet located at the top of the furnace. Air is blown upward from air outlets at the bottom of the furnace, forming a fluidized bed. The sand, which acts as a heat transfer medium, is discharged from the furnace along with non-combustible waste (hereinafter referred to as "gasifier metal") introduced from above the bottom of the furnace through a discharge chute extending downward from the bottom of the furnace. The discharged gasifier metal and sand are sieved using a sieving machine, and the sand is then re-introduced into the furnace from above the bottom of the furnace through a circulation passage. Meanwhile, the gasifier metal is separated into large iron scrap (gasifier ferrous metal) and other scrap (gasifier non-ferrous metal). The non-ferrous metal is further sieved into gasifier slag containing copper and precious metals that fall below the sieve and gasifier mixed metal containing stainless steel and aluminum scrap that fall above the sieve. The sand is crushed in a crusher, and the fine iron is collected as iron sand using a magnetic separator.

[0011] After magnetic separation, the gasifier non-ferrous metals contain not only aluminum scrap but also stainless steel scrap. Because stainless steel scrap and aluminum scrap contain high amounts of Cr, Ni, and Al, which inhibit copper smelting, it is desirable to remove these scraps before feeding them into the copper smelting process. Compared to gasifier E-slag, stainless steel scrap and aluminum scrap contain relatively large pieces in the raw material, making them difficult to reduce in size when crushed. Therefore, they can be sieved using holes in a punched metal or similar. This is because stainless steel scrap and aluminum scrap remain on the sieve, while other fine scrap parts containing copper and precious metals, as well as sand, which are prevalent in gasifier E-slag, fall below the sieve. This allows the stainless steel scrap, aluminum scrap, and other scraps to be separated and recovered after the sand has been removed. Copper smelting flash furnaces can accept gasifier E-slag containing sand.

[0012] Copper contained in gasifier scrap is often recovered as copper wire scrap. This copper wire scrap includes thin, linear copper wire scrap and clumped copper wire scrap, which is entangled with other copper wire scrap and has a steel wool-like shape. Once this clumped copper wire scrap is caught and retained in a sieve, it becomes entangled with other processing objects, clogging the mesh and reducing separation accuracy. This necessitates interrupting the sieving process to remove it. Therefore, in order to reduce processing interruptions and improve productivity, a means for efficiently separating clumped copper wire scrap is needed. While the above example concerns copper wire scrap, this separation issue exists not only for copper wire scrap but also for processing objects containing clumped wire scrap.

[0013] The present invention has been completed in view of the above problems, and in one embodiment, it is an object of the present invention to provide a processing method that can suppress the accumulation of clumped wire scraps, which are clumped objects to be processed contained in an object to be processed. In a preferred embodiment of the present invention, it is an object of the present invention to provide a processing method that can suppress the accumulation of clumped copper wire scraps, which is one form of clumped wire scraps.

[0014] After extensive research, the inventors have found that the shape of the object to be processed affects the retention of clumped scrap. Specifically, there are roughly four types of objects to be processed: wire, plate, rod, and clump. It has been found that when using a sieve that utilizes holes in a punched metal, the object to be processed can become trapped in the holes. In particular, when clumped or rod-shaped objects to be processed become trapped in the holes, they can also cause other objects to be trapped.

[0015] Therefore, the present inventors have focused on employing a sieve with a structure that makes it difficult for clumps of material to be caught, in order to eliminate the cause of clumps of material being retained. However, when clumps of material are mixed with rod-shaped material, the rod-shaped material may stand perpendicular or at an angle to the holes, causing the clumps to be trapped.

[0016] Therefore, as will be described later, it was discovered that by making the length of the flat portion of the sieve where no holes are present longer than in the prior art, and further by setting the gap between the comb-tooth portion and the flat portion of two adjacent screens within a certain range, it is possible to effectively suppress the retention of clumps of material to be treated caused by rod-shaped material to be treated. The present invention was completed based on the above findings, and is exemplified below.

[0017] [1] A method for treating objects including rod-shaped and clumped objects, comprising sieving the objects while conveying them using a vibrating sieve having a plurality of screens arranged in a conveying direction, wherein each screen has a plate-shaped flat portion and a comb-like portion, and except for the screen furthest downstream in the conveying direction, the comb-like portion of each screen overlaps with a portion of the flat portion of an adjacent screen downstream in the conveying direction to form a plurality of openings, where D is the diameter of the openings and L1 is the length of the flat portion in the conveying direction, and where H is the gap between the comb-like portions and the flat portions of the two screens forming the openings, the relationship is 2×D≦L1≦10×D, and where H is the distance between the comb-like portions and the flat portions of the two screens forming the openings, and the relationship is 0.2×D≦H≦0.5×D, and the clumped objects are collected on the sieve by the sieving. [2] The method according to [1], wherein the diameter D of the openings is 8 to 20 mm. [3] The processing method according to [1] or [2], wherein each screen further has a skirt portion extending from the flat portion downward from the perforations, and wherein, when the length of the skirt portion is L2, the relationship 1 × D ≦ L2 ≦ 5 × D is satisfied. [4] The processing method according to any one of [1] to [3], wherein the perforations are horseshoe-shaped, trapezoidal, rectangular, or triangular. [5] The processing method according to any one of [1] to [4], wherein the object to be processed further includes linear and / or plate-shaped object to be processed, and the method further comprises, after the sieving, sieving the object to be processed on the sieve using a comb-teeth vibrating sieve having multiple slits. [6] The processing method according to [5], wherein the interval L3 between the multiple slits is 50 to 150 mm. [7] The processing method according to any one of [1] to [6], wherein the raw material of the object to be processed includes automobile shredder dust, home appliance shredder dust, or electronic / electrical device part scraps. [8] The treatment method according to [5] or [6], wherein the object to be treated includes stainless steel scraps and / or aluminum scraps, and the method includes recovering the stainless steel scraps and / or aluminum scraps by sieving using a comb-tooth vibrating sieve having the plurality of slits.[9] The processing method according to any one of [1] to [8], wherein the material to be processed is automobile shredder dust, home appliance shredder dust, or crushed electronic and electrical equipment part scraps, which have been processed in a gasification melting furnace to remove combustible components such as resins, and then magnetic substances have been removed by magnetic sorting or the like.

[10] The processing method according to [9], wherein the processing in the gasification melting furnace is carried out under conditions of an air ratio of 1 or less and a temperature of 400 to 600°C.

[11] The processing method according to any one of [1] to

[10] , wherein the lumpy material to be processed includes lumpy wire scraps formed by entangled wire scraps.

[12] The processing method according to any one of [1] to

[11] , wherein the lumpy material to be processed includes lumpy copper wire scraps formed by entangled copper wire scraps.

[0018] According to the present invention, it is possible to provide a processing method that can suppress the accumulation of clumps of processing material contained in the processing material.

[0019] Fig. 1 is a schematic diagram of the configuration of a vibrating sieve in one embodiment of the present invention. Fig. 1(A) is a top view, and Fig. 1(B) is a side view. Fig. 2 is a schematic diagram of the configuration of a comb-shaped vibrating sieve having multiple slits in one embodiment of the present invention.

[0020] Next, an embodiment of the present invention will be described. It should be understood that the present invention is not limited to the following embodiment, and that appropriate design changes, improvements, etc. may be made based on the ordinary knowledge of those skilled in the art without departing from the spirit of the present invention.

[0021] (1. Processing Object) Processing objects include rod-shaped and lump-shaped processing objects. Various other processing objects, including wire-shaped and plate-shaped objects, can also be used as processing objects. Each shape of processing object is expected to be a metal material, but the specific composition is not limited. In this embodiment, the lump-shaped processing object includes lump wire scraps, and in particular, lump copper wire scraps will be described. Furthermore, in this embodiment, processing objects made from ASR, home appliance shredder dust, or electronic / electrical device part scraps will be described. ASR, home appliance shredder dust, and electronic / electrical device part scraps can be appropriately crushed and sorted, then treated in a gasification melting furnace or the like to remove combustible components such as resins, and then magnetic materials such as iron scraps can be removed by magnetic sorting or the like. Note that, since automobiles and home appliances typically contain electronic / electrical devices, ASR and home appliance shredder dust may also include electronic / electrical device part scraps. Since the shapes of the objects to be processed are diverse, there are no strict standards for the rod-shaped and block-shaped shapes mentioned above. However, generally, rod-shaped objects are hard and difficult to bend, and have an aspect ratio (the ratio of the longest diameter to the shortest diameter measured in three dimensions) of 3 or more, while block-shaped objects have an aspect ratio of less than 3.

[0022] The material to be treated from which the magnetic substances have been removed may contain stainless steel scraps and / or aluminum scraps that cannot be completely removed by magnetic separation, and these scraps contain Cr, Ni, or Al, which are copper smelting inhibitors. As will be described later, in some embodiments of the present invention, the stainless steel scraps and / or aluminum scraps can be separated by sieving using a comb-shaped vibrating sieve having multiple slits.

[0023] In addition, a gasification and melting furnace typically operates in a reducing atmosphere, which prevents rapid combustion of combustible materials while thermally decomposing and gasifying waste plastics such as resins. In this case, the internal circulation fluidized bed gasification furnace is expected to be effective in preventing oxidation of metals such as copper, iron, stainless steel, and aluminum. Therefore, the separated stainless steel scrap and / or aluminum scrap can be expected to be recovered in a state where oxidation is suppressed. Since stainless steel scrap and / or aluminum scrap in an oxidation-suppressed state is easy to process, the Fe and Al elements contained therein can be easily reused.

[0024] In this way, the gasification melting furnace is expected to have the effect of suppressing oxidation in a reducing atmosphere, but the same effect can be expected from any furnace that can perform processing in a similar reducing atmosphere, so the processing furnace for gasifying ASR, home appliance shredder dust, and electronic and electrical equipment part scraps after appropriate crushing and sorting can be any furnace that has a reducing atmosphere, and is not limited to a gasification melting furnace. The type of reducing atmosphere is also not limited, and can be, for example, hydrogen (H2), carbon monoxide (CO), hydrocarbon gas (CH4, C3H8, C4H 10 Alternatively, by setting the air ratio (the ratio between the amount of air theoretically required to completely burn the fuel (theoretical air amount) and the amount of air actually sent in for combustion) to 1 or less during gasification, combustible materials such as ASR and home appliance shredder dust are partially burned and thermally decomposed into combustible gas and ash, and it is also possible to create a strongly reducing atmosphere inside the gasification furnace.

[0025] The temperature of the gasification treatment is not particularly limited, but since the melting point of aluminum is 660°C, it is preferable to set it to 600°C or less. This makes it easier to suppress oxidation of the stainless steel scraps and / or aluminum scraps. However, since gasification of resin components such as LDPE, HDPE, and PE is usually completed at 400°C or higher, in order to achieve the purpose of the gasification treatment, the gasification treatment temperature is preferably 400°C or higher.

[0026] Therefore, in one embodiment of the present invention, the material to be treated has undergone gasification treatment at an air ratio of 1 or less and a temperature of 400 to 600°C.

[0027] Furthermore, the material to be treated may contain valuable metals such as gold, silver, platinum, and palladium in addition to copper.

[0028] Therefore, in one embodiment of the present invention, the processing object includes rod-shaped and block-shaped processing objects, as well as wire-shaped and plate-shaped processing objects. Block-shaped processing objects may include block-shaped scrap wire formed by entanglement of wire scraps, such as copper wire scraps. Then, as described below, by sieving using a vibrating sieve having multiple screens, the block-shaped processing object is sieved onto the sieve, and the other wire-, rod-, and plate-shaped processing objects are sieved into over- and under-sieve depending on the sieve diameter. When the processing object includes stainless steel scraps and / or aluminum scraps, the raw material contains many relatively large pieces, making it difficult to reduce the size when crushed. Therefore, the stainless steel scraps and aluminum scraps are sieved onto the sieve together with the block-shaped processing object. In this way, when the material to be treated that remains on the sieve includes stainless steel scraps and / or aluminum scraps, it can be further separated into clumps of material to be treated that remain on the sieve and stainless steel scraps and / or aluminum scraps that remain below the sieve by sieving using a comb-tooth vibrating sieve with multiple slits. Note that, since complete separation of each component is impossible with sieving using a vibrating sieve, in this specification, sieving of each component does not necessarily mean complete separation.

[0029] (2. Separation of Lumped Processing Objects) As one embodiment of the lump processing object, lump wire scraps, particularly lump copper wire scraps, will be described. Copper wire scraps include thin, linear copper wire scraps and lump copper wire scraps formed by entanglement of copper wire scraps with each other, forming a steel wool-like shape. Lumped copper wire scraps are generally formed by rolling up linear objects having a diameter of about 0.05 to 0.5 mm into a lump. The diameter of the entire lump copper wire scraps is greater than the hole diameter of a typical sieve, and can reach a maximum of about 500 mm. Therefore, if the processing object is sieved using a typical sieve with multiple openings (e.g., a punched metal), the lump copper wire scraps will get caught in the openings of the sieve and become trapped, causing them to become entangled with other processing objects one after another. This necessitates interrupting the sieving process and removing the lump copper wire scraps.

[0030] As mentioned above, this phenomenon occurs when rod-shaped objects to be processed get caught in the sieve openings and rise up vertically or obliquely. These rod-shaped objects are typically metal wires approximately 0.5 to 2 mm thick and 50 to 200 mm long that are bent three-dimensionally, and the minor axis of the three-dimensional shape can be approximately 25 to 100 mm. Therefore, if rod-shaped objects to be processed do not enter the sieve openings, they will not be caught in the sieve openings. Therefore, it is conceivable to adopt a structure that makes it difficult for rod-shaped objects to enter the sieve openings. Furthermore, it is believed that this phenomenon can be improved by adopting a sieve with a structure that makes it difficult for rod-shaped objects to be caught. In this embodiment, the objects to be processed are sieved using a vibrating sieve having a specific number of screens, thereby effectively suppressing the retention of clumps of objects to be processed and separating them.

[0031] FIG. 1 is a schematic diagram showing the configuration of a vibrating sieve 1 having a plurality of screens 11 according to one embodiment of the present invention. The screen 11 has a plate-shaped flat portion 111 and a comb-tooth-shaped portion 112. The plate-shaped flat portion 111 is arranged horizontally, and the teeth of the comb-tooth-shaped portion 112 are arranged in a direction substantially perpendicular to the conveyance direction of the material to be processed and extend horizontally. Although FIG. 1 shows three screens 11, the number of screens 11 is not limited to this. Furthermore, the number of teeth of the comb-tooth-shaped portion 112 in each screen 11 does not need to be limited to the number shown in the figure.

[0032] Except for the screen 11 located at the most downstream in the conveying direction, the comb-tooth portions 112 of each screen 11 overlap with a part of the flat portion 111 of the adjacent screen 11 located downstream in the conveying direction, thereby forming a plurality of apertures 12. Here, overlapping refers to the comb-tooth portions 112 of one screen 11 appearing to overlap with the flat portion of the other screen 11 in a top view. This overlapping forms the apertures 12.

[0033] Although the apertures 12 appear closed in the top view, the comb-tooth portion 112 of one screen 11 and the flat portion of the other screen 11 are not actually in contact with each other (see Figure 1 (B)).

[0034] In this embodiment, where the length of the flat portion 111 in the conveying direction is L1 and the diameter of the openings 12 is D, it is important to satisfy the relationship 2×D≦L1≦10×D. One possible reason that rod-shaped objects to be processed may get caught in the openings of the sieve is that their center of gravity changes during the sieving process, causing their tips to rise and make them more likely to get caught in the openings of the sieve. However, if the length L1 of the flat portion 111 is 2×D or greater, the change in the center of gravity of the rod-shaped objects to be processed is reduced, making them less likely to get caught in the openings of the sieve. From this perspective, L1 is preferably 3×D or greater, more preferably 4×D or greater, and even more preferably 5×D or greater.

[0035] On the other hand, if L1 exceeds 10×D, the effect will plateau, and the entire device will need to be enlarged to ensure the length of the flat portion 111, which will increase costs. Therefore, the upper limit of L1 is set to 10×D. The upper limit of L1 is preferably 9×D or less, more preferably 8×D or less, and even more preferably 7×D or less.

[0036] The length L1 of the flat portion 111 in the conveying direction refers to the distance from the upstream end of the flat portion 111 to the upstream end of the comb-tooth portion 112 in the conveying direction (FIG. 1). If this distance is not constant, the minimum value is measured and used as the length L1 of the flat portion 111 in this embodiment.

[0037] Furthermore, in this embodiment, when the hole diameter of the apertures 12 is D and the gap between the comb-tooth portions 112 and the flat portions 111 of the two screens 11 that form the apertures 12 is H, it is important to satisfy the relationship 0.2×D≦H≦0.5×D. By setting H to 0.2×D or more, rod-shaped objects to be processed are less likely to get caught even when they enter the apertures 12, and as a result, clumps of objects to be processed are less likely to become trapped. From this perspective, H is preferably 0.25×D or more, and more preferably 0.3×D or more.

[0038] On the other hand, if H is greater than 0.5×D, the rod-shaped object to be treated is likely to stand up when entering the opening 12, and therefore the upper limit of H is set to 0.5×D. The upper limit of H is preferably 0.45×D or less, more preferably 0.4×D or less, and even more preferably 0.35×D or less.

[0039] The hole diameter D of the apertures 12 refers to the diameter of the largest inscribed circle of the apertures 12 in a top view. The gap H between the comb-tooth portions 112 and the flat portions 111 of two adjacent screens 11 refers to the vertical distance between the comb-tooth portion 112 of the upstream screen 11 and the flat portion 111 of the downstream screen 11, excluding the thickness of the comb-tooth portion 112 (FIG. 1). If the vertical distance is not constant, the minimum value is measured and used as the gap H in this embodiment. The thickness of the comb-tooth portion 112 of the upstream screen 11 is not particularly limited, as long as it has a thickness that is strong enough to withstand the weight of the material to be treated.

[0040] The shape of the apertures 12 is not particularly limited, but may be a horseshoe, trapezoid, rectangle, or triangle. Here, the shape of the apertures 12 refers to a shape surrounded by the comb-tooth portion 112 of one screen 11 and the outline of the flat portion 111 of the adjacent screen 11 located downstream in the conveying direction, as viewed from above. When the outline of the flat portion 111 is the base of the shape, the base is typically a straight line. Here, the term "horseshoe" refers to a shape in which the sides other than the base (i.e., the outline of the comb-tooth portion 112) are arched curves. When the shape of the apertures 12 is a trapezoid, rectangle, or triangle, the comb-tooth portion 112 may be formed so that these have chamfered edges.

[0041] As described above, the shape of the apertures 12 refers to the projected shape seen from above, since there is a gap H between the comb-tooth portions 112 and the flat portions 111 of two adjacent screens 11. The diameter D of the apertures 12 is also calculated based on the projected shape seen from above.

[0042] The hole diameter D of the openings 12 is preferably 8 to 20 mm. If it is 8 mm or more, linear processing objects can easily fall through the sieve. From this viewpoint, the hole diameter D of the openings 12 is more preferably 8 mm or more. If it is 20 mm or less, clumped processing objects can be more efficiently collected. From this viewpoint, the hole diameter D of the openings 12 is more preferably 15 mm or less.

[0043] In a preferred embodiment of the present invention, each screen 11 further has a skirt portion 113 extending from the flat portion 111 and downwardly of the aperture 12, and when the length of the skirt portion 113 is L2, it is preferable that the relationship 1 × D ≦ L2 ≦ 5 × D is satisfied (FIG. 1(B)).

[0044] By providing the skirt portion 113 and setting its length L2 to 1×D or more, rod-shaped objects to be treated are less likely to get caught when they enter the openings 12, and as a result, clumps of objects to be treated are less likely to become trapped. On the other hand, if L2 is greater than 5×D, the effect will plateau and the device will become excessively heavy, so the upper limit of L2 is set to 5×D. The upper limit of L2 is preferably 5×D or less, more preferably 4×D or less, and even more preferably 3×D or less.

[0045] The length L2 of the skirt portion 113 refers to the distance from the upstream end of the skirt portion 113 to the upstream end of the flat portion 111 (FIG. 1B). If this distance is not constant, the minimum value is measured and used as the length L2 of the skirt portion 113 in this embodiment.

[0046] The angle α between the skirt portion 113 and the extension line of the flat portion 111 is not particularly limited, but is preferably 10° or more from the viewpoint of preventing stick-shaped objects from getting caught. The upper limit of the angle α is not particularly limited, but is typically 90° or less.

[0047] In order to sieve the material to be treated, it is necessary to vibrate the vibrating sieve 1 while carrying out the method of this embodiment. The structure for vibrating the sieve may be a known one, and detailed description of the structure etc. will be omitted.

[0048] The above-mentioned treatment prevents stick-shaped objects from getting caught, which is the cause of clumps of objects being retained, thereby achieving the object of the present invention.

[0049] When non-ferrous metals from a gasification furnace are used as raw materials, the material to be treated that falls from the vibrating sieve 1 contains little stainless steel scrap and / or aluminum scrap, and a lot of copper and precious metals with little copper smelting inhibitors, so it can be input into copper smelting.

[0050] When non-ferrous metals are used as raw materials in a gasification furnace, the material to be processed after stainless steel scraps and / or aluminum scraps are separated mainly contains copper and precious metals as well as sand. However, since a copper smelting flash furnace can accept sand mixed in, it is possible to input the material into the copper smelting process.

[0051] (3. Separation of rod-shaped or plate-shaped processing objects) By sieving using the vibrating sieve 1, processing objects including clumped processing objects remain on the sieve, while linear processing objects fall below the sieve. The processing objects on the sieve also include rod-shaped and / or plate-shaped processing objects that have been sieved according to their size. These rod-shaped and / or plate-shaped processing objects contain a high content of stainless steel scrap and / or aluminum scrap.

[0052] In order to collect agglomerated copper wire scraps containing copper as agglomerated materials from the sieve and feed them into a copper smelting process, it is necessary to remove the rod- and / or plate-shaped materials. Therefore, the rod- and / or plate-shaped materials can be separated by sieving using a comb-teeth-shaped vibrating sieve having multiple slits.

[0053] FIG. 2 shows a schematic diagram (top view) of the configuration of a comb-shaped vibrating sieve 2 having multiple slits 21 according to one embodiment of the present invention. In this embodiment, the multiple slits 21 are arranged in parallel and tapered, with their longitudinal direction oriented parallel to the transport direction of the material being processed. The cross-sectional shape of the multiple slits 21 in a direction perpendicular to their longitudinal direction is not particularly limited and may be any shape, including rectangular, trapezoidal, circular, and semicircular. The spacing L3 between the multiple slits 21 is preferably 50 to 150 mm. A spacing L3 of 50 mm or more facilitates the plate-shaped material being filtered. From this perspective, the spacing L3 between the multiple slits 21 is more preferably 50 mm or more. A spacing L3 of 150 mm or less allows for more efficient collection of clumped copper wire scraps. From this perspective, the spacing L3 between the multiple slits 21 is not particularly limited, but is more preferably 150 mm or less. In addition, when the interval L3 between the plurality of slits 21 is not constant, the minimum value of the interval in the direction perpendicular to the conveying direction in the above top view is set as the interval L3 between the plurality of slits 21.

[0054] The length of the plurality of slits 21 can be set appropriately depending on the conveying speed of the workpieces to be processed, the required separation accuracy, etc., and can be, for example, 100 to 300 mm. Furthermore, if the length of the plurality of slits 21 is sufficient, there is no need to connect the ends of the slits, and they may be open as shown in Fig. 2. Furthermore, if the ends of the plurality of slits 21 are open, the thickness can be increased to maintain strength, or a reinforcing mechanism can be provided below (not shown).

[0055] Furthermore, the comb-tooth vibrating sieve 2 having a plurality of slits 21 may be disposed immediately downstream of the vibrating sieve 1 having a plurality of screens 11. This allows the material to be treated in one continuous process.

[0056] The treated material from which the rod-shaped and / or plate-shaped treatment materials have been separated can be used to collect lump copper wire scraps containing copper as a lump treatment material, and can be input into a copper smelting process.

[0057] The separated stainless steel scraps and aluminum scraps can be separated and collected in a state where oxidation is suppressed due to the reducing atmosphere in the gasification process.

[0058] The present invention will be specifically described below with reference to examples, but the description here is for the purpose of illustration only and is not intended to be limiting.

[0059] Example: ASR and home appliance shredder dust were treated in a fluidized bed gasifier to gasify the contained waste plastics. The treated material (gasifier non-ferrous metals) was then magnetically separated and treated using a vibrating sieve 1 shown in Figure 1. The vibrating sieve 1 had 16 screens 11, each with a flat portion length L1 of 75 mm, a skirt portion 113 length L2 of 25 mm, and an angle α of 50°. The screens 11 were arranged so that the gap H between the comb-tooth portions 112 and the flat portions 111 of the two screens 11 forming the openings 12 was 4 mm, and the opening diameter D of the openings 12 was 12 mm. In this example, the openings 12 were horseshoe-shaped.

[0060] When about 10 kg of the object to be treated was treated, all of the clumped copper wire scraps were collected on the vibrating sieve 1, and all of the linear object to be treated fell, with no residue remaining on the vibrating sieve 1.

[0061] Next, the material to be treated collected on the vibrating sieve 1 was treated using the vibrating sieve 2 shown in Fig. 2. The multiple slits 21 were parallel and spaced 80 to 120 mm apart. As a result of the treatment using the vibrating sieve 2, all of the clumped copper wire scraps were collected on the vibrating sieve 2, and all of the rod-shaped and / or plate-shaped material to be treated fell, with no material remaining on the vibrating sieve 2.

[0062] For the vibrating sieve 1, the compositions of the material above the sieve and the material below the sieve were analyzed by ICP-OES after alkali fusion to evaluate the separation rate. Specifically, since the material other than the stainless steel scrap contains almost no Cr (usually 0.5 wt % or less), the total weight of the Cr above and below the sieve was taken as 100%, and the ratio of the weight of the Cr above the sieve was used as the separation rate of the stainless steel scrap. On the other hand, since the material other than the aluminum scrap contains almost no Al, the total weight of the Al above and below the sieve was taken as 100%, and the ratio of the weight of the Al above the sieve was used as the separation rate of the aluminum scrap. As a result, the separation rates of the stainless steel scrap and the aluminum scrap were 90% or more and 40% or more, respectively.

[0063] Furthermore, when the fractured surfaces of the recovered stainless steel scraps and aluminum scraps were visually inspected, it was confirmed that the fractured surfaces had a metallic luster and were in a state where they were hardly oxidized. Furthermore, the Fe and Al elements did not become alloy metals, and they could be recovered as metals with high resource value.

[0064] (Comparative Example) The object to be processed was the same as in the Example, and the vibrating sieve had 16 screens 11, with the length L1 of the flat portion of each screen 11 being 20 mm, the length L2 of the skirt portion 113 being 50 mm, and the angle α being 37°. The gap H between the comb-tooth portions 112 and the flat portions 111 of the two screens 11 forming the apertures 12 was 2 mm, and the hole diameter D of the apertures 12 was 18 mm. In this comparative example, the shape of the apertures 12 was horseshoe-shaped.

[0065] As a result of the comparative example, a phenomenon occurred in which some rod-shaped objects to be processed got caught in the overlapping portion of the gap H, and clumps of copper wire scraps became entangled therein.

[0066] REFERENCE SIGNS LIST 1 Vibrating sieve having a plurality of screens 11 Screen 111 Flat portion 112 Comb-shaped portion 113 Skirt portion 12 Opening 2 Comb-shaped vibrating sieve having a plurality of slits 21 Slit

Claims

1. A method for processing objects including rod-shaped objects and chunk-shaped objects, comprising: sieving the objects using a vibrating sieve having a plurality of screens arranged along a conveying direction while conveying the objects; each screen has a plate-shaped flat portion and a comb-shaped portion; except for the screen located at the most downstream side in the conveying direction, the comb-shaped portion of each screen overlaps with a part of the flat portion of an adjacent screen located downstream in the conveying direction to form a plurality of openings; the diameter of the openings is D, and the length of the flat portion in the conveying direction is L. 1 In this case, 2×D≦L 1 ≦10×D, and when the gap between the comb-tooth portions and the flat portions of the two screens that form the openings is H, the relationship of 0.2×D≦H≦0.5×D is satisfied, and by the sieving, clumped processing objects are collected on the sieve.

2. The method according to claim 1, wherein the aperture diameter D is 8 to 20 mm.

3. Each screen further has a skirt portion that extends from the flat portion and extends downward toward the opening, and the length of the skirt portion is L 2 When this is the case, the processing method according to claim 1 or 2, which satisfies the relationship of 1×D ≤ L 2 ≤ 5×D 4. The method according to any one of claims 1 to 3, wherein the apertures are horseshoe-shaped, trapezoidal, rectangular, or triangular.

5. A processing method according to any one of claims 1 to 4, wherein the object to be processed further includes a rod-shaped and / or plate-shaped object to be processed, and the method further comprises, after the sieving, sieving the object to be processed on the sieve using a comb-teeth shaped vibrating sieve having a plurality of slits.

6. The interval L between the plurality of slits 3 is 50 to 150 mm, and the processing method according to claim 5.

7. The processing method according to any one of claims 1 to 6, wherein the raw material to be processed includes automobile shredder dust, home appliance shredder dust, or scrap electronic and electrical equipment parts.

8. A processing method according to claim 5 or 6, wherein the object to be processed contains stainless steel scraps and / or aluminum scraps, and the method includes recovering the stainless steel scraps and / or aluminum scraps by sieving using a comb-tooth vibrating sieve having the plurality of slits.

9. A processing method according to any one of claims 1 to 8, in which the objects to be processed are automobile shredder dust, home appliance shredder dust, and crushed electronic and electrical equipment part scraps which have been processed in a gasification melting furnace to remove combustible components such as resins, and which have subsequently had magnetic substances removed by magnetic sorting or the like.

10. The treatment method according to claim 9, wherein the treatment in the gasification and melting furnace is carried out under conditions of an air ratio of 1 or less and a temperature of 400 to 600°C.

11. A processing method according to any one of claims 1 to 10, wherein the lumpy processing object includes a mass of wire scraps formed by entanglement of wire scraps.

12. A processing method according to any one of claims 1 to 11, wherein the lump-shaped processing object includes a lump-shaped copper wire scrap formed by entanglement of copper wire scraps.

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