Waste disposal system and waste disposal method

Abstract

To provide a waste treatment system which can sort non-magnetic metal and ash contained in a waste with high accuracy.SOLUTION: A waste treatment system 100 includes a moisture information acquisition part 31 for acquiring moisture information of a waste 20 containing non-magnetic metal and ash, and a sorting part 10 including an eddy current sorter 11 for sorting the waste 20 into at least a first sorted object 41 containing the non-magnetic metal and a second sorted object 42 containing the ash, and is configured to adjust a sorting condition in the sorting part 10 on the basis of the moisture information.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a waste treatment system and a waste treatment method.

Background Art

[0002] The waste such as municipal solid waste incineration ash contains various metals such as precious metals, aluminum, iron, and copper. Such metals are separated from the ash and recovered as valuable metals and recycled to effectively utilize resources. In Patent Document 1, for the purpose of efficiently recovering valuable metals and promoting the utilization of light products, a wind separator for separating metal-containing waste into light products and heavy products, and means for recovering valuable metals from the heavy products separated by the wind separator are provided. A treatment device for metal-containing waste has been proposed.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] The ash obtained by sorting waste such as incineration ash can be effectively used as, for example, a fuel source or a raw material for cement. An eddy current separator is used as a means for separating non-magnetic metals contained in the waste from the ash. Here, when the sorting accuracy in the eddy current separator decreases and non-magnetic metals are mixed into the ash, not only does the recovery rate of valuable non-magnetic metals decrease, but there is also a concern of promoting wear of, for example, raw material mills, dust collectors, fans, and flue ducts provided in cement manufacturing devices.

[0005] Therefore, the present disclosure provides a waste treatment system and a waste treatment method capable of sorting non-magnetic metals contained in waste and ash with high accuracy. [Means for solving the problem]

[0006] In one aspect, this disclosure provides a waste treatment system comprising: a moisture information acquisition unit that acquires moisture information of waste containing non-magnetic metals and ash; and a sorting unit including an eddy current separator that sorts the waste into at least a first sorted material containing non-magnetic metals and a second sorted material containing ash, wherein the sorting conditions in the sorting unit can be adjusted based on the moisture information.

[0007] Waste often contains a certain amount of moisture to adjust the moisture content at the source of discharge. Furthermore, if it contains incineration ash, cooling treatment using water may be performed for safety reasons. Our research has shown that the moisture content in the waste affects the accuracy of eddy current separation, which separates non-magnetic metals from ash. The waste treatment system described above can adjust the sorting conditions in the sorting unit, including the eddy current separator, based on moisture information acquired by the moisture information acquisition unit. Therefore, even if the moisture content of the waste fluctuates, it is possible to maintain high accuracy in eddy current separation, enabling highly accurate separation of non-magnetic metals from ash in the waste.

[0008] The waste treatment system described above may include at least one detection unit selected from the group consisting of a first detection unit for detecting ash content in the first sorted material and a second detection unit for detecting metals in the second sorted material, and may be configured to adjust the sorting conditions based on the detection results from the detection units. With such a treatment system, for example, if ash content is mixed into the first sorted material and / or if non-magnetic metals are mixed into the second sorted material, the sorting conditions can be feedback-controlled based on the detection results from the detection units. Therefore, the sorting accuracy of non-magnetic metals and ash content in the waste can be further improved.

[0009] This disclosure provides a waste treatment system comprising, in one aspect, a sorting unit including an eddy current separator that sorts waste containing non-magnetic metals and ash into at least a first sorted material containing non-magnetic metals and a second sorted material containing ash, and at least one detection unit selected from the group consisting of a first detection unit that detects ash contained in the first sorted material and a second detection unit that detects metals contained in the second sorted material, wherein the sorting conditions in the sorting unit can be adjusted based on the detection results of the detection units.

[0010] The waste treatment system described above includes a first detection unit that detects the presence of ash in the first sorted material, and / or a second detection unit that detects the presence of non-magnetic metals in the second sorted material. Based on the detection results from the first and / or second detection units, the sorting conditions by the sorting unit, including the eddy current separator, are adjusted. Therefore, even if the size or material of the waste changes, for example, it is possible to maintain a high sorting accuracy by the eddy current separator, and non-magnetic metals and ash contained in the waste can be separated with high precision.

[0011] The adjustment of the sorting conditions described above may include moving at least a portion of the partitioning member that separates the drop areas of the first sorted material and the second sorted material relative to the eddy current separator. This allows for easy adjustment of sorting conditions while achieving sufficiently high sorting accuracy.

[0012] The eddy current separator is of the rotary magnet type, and adjusting the sorting conditions may include changing the speed at which the belt supplying the waste onto the rotating magnetic drum moves. This allows for smooth adjustment of sorting conditions with a simple device configuration, thereby achieving sufficiently high sorting accuracy.

[0013] The waste treatment system described above may include a magnetic separation unit upstream of the sorting unit, which separates at least a portion of the magnetic metal from the first waste containing magnetic metal, non-magnetic metal, and ash to obtain a second waste with a reduced amount of magnetic metal compared to the first waste, and this second waste may be used as the waste. This allows for the smooth separation and effective utilization of waste containing magnetic metal, non-magnetic metal, and ash.

[0014] This disclosure provides a waste treatment method comprising, in one aspect, a moisture information acquisition step for acquiring moisture information of waste containing non-magnetic metals and ash, and a sorting step for sorting the waste into a first sorted material containing at least non-magnetic metals and a second sorted material containing ash using an eddy current separator, wherein the sorting step adjusts the sorting conditions based on the moisture information.

[0015] The moisture content in waste affects the sorting accuracy of eddy current separators, which separate non-magnetic metals from ash. However, the waste treatment method described above adjusts the sorting conditions of the eddy current separator based on the moisture information obtained in the moisture information acquisition step. Therefore, even if the moisture content of the waste fluctuates, it is possible to maintain high sorting accuracy with the eddy current separator, enabling highly accurate separation of non-magnetic metals from ash in the waste.

[0016] The waste treatment method described above includes a detection step for detecting at least one selected from the group consisting of ash contained in the first sorted material and metals contained in the second sorted material, and the sorting conditions may be adjusted based on the detection results in the detection step. With such a treatment method, for example, if ash is mixed into the first sorted material and / or if non-magnetic metals are mixed into the second sorted material, the sorting conditions can be feedback-controlled based on the detection results in the detection step. Therefore, the sorting accuracy of non-magnetic metals and ash contained in the waste can be further improved.

[0017] This disclosure provides a waste treatment method comprising, in one aspect, a sorting step of sorting waste containing non-magnetic metals and ash into a first sorted material containing at least non-magnetic metals and a second sorted material containing ash using an eddy current separator, and a detection step of detecting at least one selected from the group consisting of ash contained in the first sorted material and metals contained in the second sorted material, wherein the sorting step adjusts the sorting conditions based on the detection results in the detection step.

[0018] The waste treatment method described above involves a detection step to detect if ash is present in the first sorted material and / or if metal is present in the second sorted material. Based on the detection results in this detection step, the sorting conditions in the sorting step are adjusted. Therefore, even if the size or material of the waste changes, for example, it is possible to maintain a high level of sorting accuracy and to sort non-magnetic metals and ash contained in the waste with high precision.

[0019] The adjustment of sorting conditions in the above sorting process may include moving at least a portion of the partitioning member separating the first sorted material and the second sorted material relative to the eddy current separator. This allows for easy adjustment of sorting conditions while ensuring sufficiently high sorting accuracy.

[0020] In the above sorting process, a rotating magnet type eddy current separator is used, and adjusting the sorting conditions in the above sorting process may include changing the movement speed of the belt that supplies waste onto the rotating magnet drum of the eddy current separator. This allows for smooth adjustment of sorting conditions with a simple device configuration, thereby achieving sufficiently high sorting accuracy.

[0021] The waste treatment method described above includes a magnetic separation step in which magnetic metals are separated from a first waste containing magnetic metals, non-magnetic metals, and ash to obtain a second waste with a reduced amount of magnetic metals compared to the first waste, and the second waste may be used as the aforementioned waste. This allows for the smooth separation and effective utilization of waste containing magnetic metals, non-magnetic metals, and ash. [Effects of the Invention]

[0022] It is possible to provide a waste treatment system and a waste treatment method capable of sorting non-magnetic metals and ash contained in waste with high precision. The ash obtained by such a waste treatment system and waste treatment method has sufficiently reduced contamination of non-magnetic metals. Therefore, when such ash is used, for example, in the production of cement, wear in raw material mills, dust collectors, fans, and flue ducts can be sufficiently suppressed. In addition, non-magnetic metals useful as recycled resources can be sufficiently recovered.

Brief Description of the Drawings

[0023] [Figure 1] It is a diagram showing an example of a waste treatment system. [Figure 2] It is a diagram showing an example of a control unit for adjusting sorting conditions and an example of input / output of information in the control unit. [Figure 3] It is a diagram showing another example of a waste treatment system. [Figure 4] It is a diagram showing an example of a roll screen in a waste treatment system.

Modes for Carrying Out the Invention

[0024] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings as appropriate. However, the following embodiments are examples for explaining the present disclosure and are not intended to limit the present disclosure to the following content.

[0025] The waste treatment system (treatment equipment) according to this embodiment includes: a moisture information acquisition unit that acquires moisture information of waste containing non-magnetic metals and ash; a sorting unit (eddy current sorting unit) including an eddy current separator that sorts the waste into at least a first sorted material containing non-magnetic metals and a second sorted material containing ash; and at least one detection unit selected from the group consisting of a first detection unit that detects ash contained in the first sorted material and a second detection unit that detects metals contained in the second sorted material. The sorting conditions by the eddy current sorting unit are adjusted based on at least one selected from the group consisting of the moisture information of the waste, the detection result by the first detection unit, and the detection result by the second detection unit. The metal detected by the second detection unit may be a magnetic metal or a non-magnetic metal. The sorting conditions may be adjusted, for example, by a control unit.

[0026] Non-magnetic metals found in waste include aluminum, copper, zinc, silver, gold, and rare metals. Non-magnetic metals are defined as metals other than magnetic metals. By separating these from ash, they become high-value-added recycled materials. Increasing the amount of such recycled materials recovered can significantly reduce waste disposal costs.

[0027] The ash content in waste includes coal ash, incinerated plastics and rubber, etc. By separating the ash from metals, it can be suitably used as fuel and raw material for cement production. Reducing the metal content of the ash used in such applications can suppress wear in the flue of raw material mills and other components.

[0028] Figure 1 shows an example of a waste treatment system according to this embodiment. The waste treatment system 100 in Figure 1 includes a transport unit 60 that transports waste 20 containing non-magnetic metal 21 and ash 22, and a vibrating feeder 62 that vibrates the waste 20 transported by the transport unit 60 to level the powdery or lumpy waste 20 and supplies the waste 20 to an eddy current separation unit 10 (separation unit 10). The eddy current separation unit 10 includes a rotary magnet type eddy current separator 11 and a partitioning member 50 that divides the fall area between the first sorted material and the second sorted material sorted by the eddy current separator 11.

[0029] The conveying section 60 is, for example, a conveyor. Upstream of the conveying section 60, a crushing device and a magnetic separator may be provided. By leveling the waste 20 with the vibrating feeder 62, the sorting accuracy in the eddy current separator 10 can be improved. Alternatively, a vibrating conveyor and a vibrating screen may be provided instead of, or in conjunction with, the vibrating feeder 62.

[0030] The eddy current separator 11 is provided with a magnet drum 14 on which multiple magnets 15 are arranged so that their magnetic poles are alternately aligned along the circumference. A hollow rotating drum 17 is provided on the outer circumference of the magnet drum 14 so as to be concentric with the magnet drum 14. Furthermore, a roller 13 is provided that rotates in the same direction as the rotating drum 17, in conjunction with the rotating drum 17. In a modified example, the magnet drum 14 may rotate in the opposite direction to the roller 13 and the rotating drum 17. A belt 12 (feed belt) for conveying waste 20 is stretched between the rotating drum 17 and the roller 13. The magnet drum 14 is held inside the rotating drum 17 so as to be able to rotate at a higher speed than the rotating drum 17. The rotational speed of the magnet drum 14 may be, for example, 3000 to 3600 rpm.

[0031] The waste 20, transported by the belt 12 and reaching the magnetic drum 14, is subjected to the effects of the changing magnetic field. Eddy currents are generated in the conductive non-magnetic metal 21 contained in the waste 20. This creates a repulsive force between the waste and the alternately changing magnetic field, causing it to bounce away and fall. Through this action, the non-magnetic metal 21 falls over the upper end of the partition member 50 and into an area away from the magnetic drum 14. In this way, the first sorted material 41 containing the non-magnetic metal 21 is obtained.

[0032] On the other hand, the ash 22 does not experience magnetic activity even when it reaches the magnetic drum 14, and falls downward due to gravity, despite the inertial force from the conveying belt 12. As a result, the ash 22 does not exceed the upper end of the partition member 50 and falls in an area closer to the eddy current separator 11 than the non-magnetic metal 21. In this way, a second sorted material 42 containing ash 22 is obtained.

[0033] The partitioning member 50 has a swinging part 51 at its upper end, a support part 55 at its base end, and a swing shaft 53 between the swinging part 51 and the support part 55. The swinging part 51 is provided so as to be able to swing with the swing shaft 53 as a fulcrum. As the swinging part 51 swings and moves, the angle θ between the swinging part 51 and the support part 55 changes. In this way, the partitioning position of the drop area for the first sorted material and the second sorted material changes, and the sorting conditions of the waste 20 are adjusted.

[0034] A moisture meter 31 (moisture information acquisition unit) is provided near the transport unit 60. A non-contact online analyzer can be used as the moisture meter 31. For example, one that utilizes absorption in the near-infrared region (NIR) can be used. Based on the moisture concentration (moisture information) measured by such a moisture meter, the sorting conditions in the eddy current sorting unit 10 are adjusted. Specifically, the oscillating unit 51 in the partition member 50 is oscillated to change the angle θ. In this way, the sorting conditions of the waste 20 are adjusted based on the moisture concentration. The operation of the oscillating unit 51 may be controlled by the control unit. The moisture content of the waste 20 may be, for example, 10 to 30 mass%.

[0035] When the moisture concentration of the waste 20 increases, the area in which the waste 20 falls in the eddy current separation unit 10 changes. One possible reason for this is that when the moisture concentration increases, ash 22, such as incineration ash, is more likely to adhere to the metal fragments of the non-magnetic metal 21. For example, when the moisture concentration increases, the non-magnetic metal 21 (non-magnetic metal fragments) to which ash 22 has adhered becomes less likely to be bounced far away by the magnetic drum 14, and is more likely to be mixed into the second sorted material 42. In such cases, the oscillating part 51 in the partition member 50 is oscillated so that it moves toward the eddy current separation machine 11 (the angle θ is reduced). This makes it possible to reduce the amount of non-magnetic metal 21 mixed into the second sorted material 42. Therefore, the amount of first sorted material 41 recovered can be sufficiently increased, and wear on the flue of the rotary mill and raw material mill can be sufficiently suppressed when the second sorted material 42 is used in cement manufacturing equipment, etc.

[0036] In the example shown in Figure 1, the partition member 50 has a swinging part 51 at its upper end, but the structure is not limited to this. In a modified example, the partition member 50 may be made of a partition plate, and the entire partition member 50 may move relative to the eddy current separator 11 so that the distance between the eddy current separator 11 and the partition member 50 changes. In this case, the sorting conditions of the waste 20 are adjusted by moving the entire partition member 50, the eddy current separator 11, or both.

[0037] In another modification, the sorting conditions for the waste 20 may be adjusted by changing the speed at which the belt 12 moves. Increasing the speed at which the belt 12 moves increases the inertial force of the waste 20 as it falls from the belt 12, causing the fall position of the waste 20 to move away from the eddy current separator 11 (magnetic drum 14). When the moisture concentration of the waste 20 is high, increasing the speed at which the belt 12 moves can reduce the amount of non-magnetic metal 21 mixed into the second sorted material 42. In this case, the partition member 50 may remain fixed, or it may move along with the change in the speed at which the belt 12 moves.

[0038] The waste treatment system 100 includes a first detection unit 34 that detects ash content 22 contained in the first sorted material 41 sorted by the eddy current sorting unit 10, and a second detection unit 32 that detects non-magnetic metals 21 contained in the second sorted material 42 sorted by the eddy current sorting unit 10. The first detection unit 34 can, for example, analyze and diagnose an image of the first sorted material to determine whether or not ash content 22 is present. The second detection unit 32 can use X-rays to determine whether or not metal (non-magnetic metal 21) is present. When metal contamination is detected by the second detection unit 32, and / or when ash content 22 is detected by the first detection unit 34, the sorting conditions in the eddy current sorting unit 10 are adjusted. As described above, the sorting conditions can be adjusted by moving (oscillating) the oscillating part 51 of the partition member 50, moving the entire partition member 50, moving the eddy current separator 11, or changing the speed of movement of the belt 12. Alternatively, it may be done by changing the rotation speed (number of rotations) of the magnetic drum 14.

[0039] For example, if the first detection unit 34 detects the presence of ash 22 in the first sorted material, the oscillation unit 51 is oscillated to move away from the eddy current separator 11 based on the detection result, thereby increasing the angle θ. This reduces the amount of ash 22 mixed into the first sorted material 41. Alternatively, instead of oscillating the oscillation unit 51, or in conjunction with oscillating it, the movement speed of the belt 12 may be reduced.

[0040] A target value (upper limit) may be set for the amount of ash 22 mixed into the first sorted material, and the sorting conditions based on the detection results of the first detection unit 34 and the second detection unit 32 may be adjusted by feedback control using the control unit. This makes it possible to sufficiently increase the sorting accuracy of the waste 20.

[0041] The sorting conditions in the eddy current sorting unit 10 may be adjusted using a control unit 30 as shown in Figure 2. The control unit 30 can be configured as a normal computer system. For example, the control unit 30 may include a processor, memory, storage, and a circuit having input / output ports. The moisture concentration measured by the moisture meter 31, the detection result of the first detection unit 34, and the detection result of the second detection unit 32 are input to the control unit 30.

[0042] The storage of the control unit 30 may store table data or functions showing the relationship between the moisture content of the waste 20 and the angle θ of the oscillating unit 51, or the relationship between the moisture content of the waste 20 and the angle θ of the oscillating unit 51. It may also store table data or functions showing the relationship between the detection results from the first detection unit 34 and the second detection unit 32 and the movement speed of the belt 12. The storage may also store computer software that calculates output information based on the data input to the control unit 30.

[0043] The control unit 30 loads such computer software onto hardware such as the processor and memory, and calculates a control signal based on the information (moisture information and detection results) input to the control unit 30 under the control of the processor. The storage may be a computer-readable recording medium such as a hard disk, non-volatile semiconductor memory, magnetic disk, or optical disk. The control unit 30 may have a memory that temporarily stores the program and data loaded from the storage, as well as the calculation results of the processor, and the processor may work with the memory to derive the control signal.

[0044] The control signals output from the control unit 30 are input to one or more of the drive units 13A that drive the rollers 13 of the eddy current separator 11, 14A that rotates the magnet drum 14, and 50A that oscillate the oscillating unit 51. The drive units 13A, 14A, and 50A may be actuators, and specifically motors. The control unit 30 may have a function to select whether to output control signals to one or more of the drive units 13A, 14A, and 50A depending on the input information (moisture information and detection results). In this way, the sorting conditions in the eddy current separator 10 may be adjusted. Note that the waste processing system 100 does not necessarily have such a control unit 30. For example, based on moisture information or detection results from the first detection unit 34 and the second detection unit 32, the operator may manually change the angle θ between the oscillating unit 51 and the support unit 55, or change the moving speed of the belt 12.

[0045] The examples in Figures 1 and 2 include a moisture meter 31, a first detection unit 34, and a second detection unit 32, but are not limited thereto. For example, in a modified example, there may be only one or two selected from the moisture meter 31, the first detection unit 34, and the second detection unit 32. Also, the control unit 30 may be configured to control only one of the drive unit 13A and the drive unit 50A. In another modified example, the drive unit 50A may be configured to move the entire position of the partition member, or it may be configured to move the eddy current separator 11.

[0046] The waste may contain components other than non-magnetic metals and ash. For example, it may contain sludge, landfill soil, coal ash, concrete debris, shredder dust, ASR, and waste glass. If the content of such components is high, for example, another separator may be installed upstream of the eddy current separator 11 to remove magnetic metals such as iron and other nonmetals from the waste. This allows for stable and continuous operation of the eddy current separator.

[0047] Figure 3 shows another example of the waste treatment system of this embodiment. The waste treatment system 200 in Figure 3 includes a receiving hopper 71 that receives first waste containing magnetic metals, non-magnetic metals, and ash, etc., a first magnetic separator 72 that separates the first waste from the receiving hopper 71 into magnetic and non-magnetic materials, a separation device 73 that removes at least a portion of the deposits adhering to the magnetic metal contained in the magnetic materials by vibration to obtain metal-containing materials, a roll screen 74 that separates the non-magnetic materials into sieved materials, unsieved materials, and coarse materials having a size larger than the sieved materials, a crushing device 75 that crushes the sieved materials obtained by the roll screen 74 to obtain crushed materials, and a second magnetic separator 76 that, after combining the metal-containing materials obtained by the crushing device 75 and the separation device 73, separates the metal-containing materials into magnetic metals and second waste containing non-magnetic metals and ash. The second waste is suitable as waste supplied to the eddy current separation unit 10 because it contains significantly less magnetic metal than the first waste. Magnetic metal refers to metals that exhibit ferromagnetism, such as iron, cobalt, and nickel.

[0048] The eddy current separation unit 10 in the waste treatment system 200 in Figure 3 may have the same configuration as the eddy current separation unit 10 in Figure 1. A conveying unit 60 and a vibrating feeder 62, as shown in Figure 1, may be placed between the second magnetic separator 76 and the eddy current separation unit 10.

[0049] The receiving hopper 71 may have a grizzly filter at the upper feed port into which the first waste is supplied. This allows for the removal of large metal fragments contained in the first waste. Therefore, the load on equipment downstream of the receiving hopper 71 can be reduced. The large metal fragments may be utilized as recyclable resources.

[0050] The first magnetic separator 72 separates the first waste introduced from the receiving hopper 71 into magnetic material containing magnetic metals and non-magnetic material containing non-magnetic metals. The first magnetic separator 72 may be, for example, a metal separator equipped with a magnetic field sensor. Examples of the first magnetic separator 72 include dry magnetic separators such as suspended magnetic separators and drum magnetic separators, and wet magnetic separators. Of these, it is preferable to use a dry magnetic separator because it eliminates the need for dewatering and drying of the first waste. The non-magnetic material has a lower magnetic metal content than the first waste and the magnetic material. On the other hand, the magnetic material has a higher magnetic metal content than the first waste and the non-magnetic material. The magnetic metal contained in such magnetic material may have ash or other deposits attached to it.

[0051] In the separation device 73, at least a portion of the deposits adhering to the magnetic metal contained in the magnetic material are separated by vibration. By separating the deposits, the separation device 73 obtains a metal-containing material with a higher magnetic metal content than the magnetic material. The separation device may be a vibratory feeder, and the deposits may be separated by vibration, water washing, and air power treatment simultaneously or sequentially. The separated deposits are, for example, ash. The deposits removed from the magnetic metal in this way may be part of the waste (second waste) supplied to the eddy current separation unit 10, or they may be combined with the second sorted material sorted in the eddy current separation unit 10. Alternatively, they may be used as fuel or raw material for cement production.

[0052] The Roll Screen 74 sieves non-magnetic materials, separating them into sieved material, unsieved material, and coarse material larger than the sieved material. The coarse material includes large metal fragments containing non-magnetic metals. Because the coarse material has a high non-magnetic metal content, it is easy to recycle and has high added value as a recyclable resource.

[0053] The sieved material contains non-magnetic metals and ash, and is smaller in size than the coarse material. Therefore, it can be smoothly crushed in the downstream crushing device 75. The unsieved material may contain ash or combustible materials, and may be used as fuel or raw material for cement production. It may also be part of the waste (second waste) supplied to the eddy current separation unit 10.

[0054] Figure 4 is a side view of an example of a roll screen 74 in the waste treatment system 200. The roll screen 74 comprises a frame 82 inclined such that one end is higher than the other with respect to the horizontal plane, and a plurality of rollers 81 arranged at predetermined intervals along the frame 82. Each roller 81 has a rotating shaft 85 and a plurality of rotating plates 84 attached to the rotating shaft 85 and arranged along the axial direction. Multiple rotating plates 84 are provided at predetermined intervals along the axial direction of the rotating shaft 85. The rollers 81 rotate clockwise around the rotating shaft 85. The roll screen 74 is inclined so that it is higher in the direction of travel of the non-magnetic material supplied onto the rollers 81.

[0055] When non-magnetic material is supplied onto the rotating roller 81 from above the roll screen 74, fine particles such as ash contained in the non-magnetic material fall below the roller 81 through the gaps between adjacent rollers 81 and the gaps between adjacent rotating plates 84. The fallen fine particles are collected in the hopper 83 and recovered as sieved material. Larger metal fragments and other materials contained in the non-magnetic material fall downward and to the left due to gravity, opposite to the direction of rotation of the roller 81, and are recovered as coarse material. On the other hand, metal fragments smaller than the coarse material move upward and to the right due to the rotation of the roller 81 and are recovered as sieved material. The roll screen 74 in Figure 4 may be equipped with a hopper for recovering coarse material and sieved material. The separation ratio of coarse material and sieved material can be adjusted by the inclination angle of the frame 82 and the rotation speed of the roller 81. The inclination angle of the frame 82 with respect to the horizontal plane may be, for example, 30 to 60°. The separation ratio between the sieved material and the unsieved material can be adjusted by changing the spacing between adjacent rollers 81 and adjacent rotating plates 84.

[0056] Returning to Figure 3, the crushing device 75 crushes the sieved material obtained by the roll screen 74 to obtain metal-containing material. Since the sieved material has a sufficiently reduced amount of large metal fragments compared to the waste, the load on the crushing device 75 can be sufficiently reduced. For example, this is preferable in that it can improve processing capacity when the processing speed of the crushing device 75 is the rate-limiting factor in the processing speed of the waste processing system 200. Examples of the crushing device 75 include a conventional single-shaft crusher, twin-shaft crusher, pulverizer, hammer crusher, and chain crusher. The crushing device 75 may be equipped with one of these individually or in combination of two or more types. The crushing device 75 can crush metal fragments into smaller pieces. Since the size variation of the crushed material obtained in this way is sufficiently small, it can be sorted with high precision by the eddy current sorting unit 10.

[0057] In the second magnetic separator 76, the metal-containing material obtained in the crusher 75 and the separator 73 is separated into magnetic metal and second waste containing non-magnetic metal and ash. The waste treatment system 200, like the waste treatment system 100, has a moisture meter 100 to measure the moisture content of the second waste. The waste treatment system 200 is also configured to adjust the sorting conditions of the eddy current separator 10 according to the moisture content of the second waste.

[0058] The second magnetic separator 76 may be a metal separator equipped with a magnetic field sensor, similar to the first magnetic separator 72. Examples of the second magnetic separator 76 include dry magnetic separators such as suspended magnetic separators and drum magnetic separators, as well as wet magnetic separators. Of these, it is preferable to use a dry magnetic separator because it eliminates the need for dewatering and drying of the waste. Since the second magnetic separator 76 is supplied with metal-containing material with reduced ash content, it can separate magnetic metal fragments with higher precision than the first magnetic separator 72. The magnetic metal fragments separated in this way have a low ash content and a high magnetic metal content. Therefore, they have high added value as a recyclable resource. Since the separated second waste has a sufficiently reduced content of large metal fragments and magnetic metals, using such second waste as raw material allows for smooth separation of non-magnetic metals and ash in the eddy current separator 10.

[0059] In the eddy current separation unit 10, the second waste is separated into first sorted material and second sorted material. The waste treatment system 200, like the waste treatment system 100, is equipped with a first detection unit 34 and a second detection unit 32, and is configured to adjust the sorting conditions of the eddy current separation unit 10 based on the detection results of these units. The waste treatment system 200 had, but is not limited to, a first magnetic separator 72 and a second magnetic separator 76 as a magnetic separator unit.

[0060] A waste treatment method according to one embodiment includes: a moisture information acquisition step of acquiring moisture information of waste containing non-magnetic metals and ash; a sorting step of sorting the waste into a first sorted material containing at least non-magnetic metals and a second sorted material containing ash using an eddy current separator; and a detection step of detecting at least one selected from the group consisting of ash contained in the first sorted material and non-magnetic metals contained in the second sorted material. In the sorting step, the sorting conditions for sorting the first sorted material and the second sorted material may be adjusted based on the moisture information, or the sorting conditions may be adjusted based on the detection results in the detection step. The adjustment of the sorting conditions includes at least one selected from the group consisting of moving at least a part of a partitioning member separating the first sorted material and the second sorted material relative to the eddy current separator, changing the rotation speed (number of rotations) of the magnetic drum, and changing the movement speed of the belt that supplies waste onto the rotating magnetic drum.

[0061] For example, when using the waste treatment system 100, moving at least a portion of the partition member 50 relative to the eddy current separator 11 may be done by the oscillating unit 51 oscillating, moving the entire partition member 50 relative to the eddy current separator 11, or moving the eddy current separator 11 relative to the partition member 50.

[0062] The processing method described above may be carried out using the waste processing system 100 or the waste processing system 200, or using variations thereof. Therefore, the description of the waste processing system described above also applies to the waste processing method of this embodiment. For example, in the sorting process, the sorting conditions may be adjusted using the control unit 30 shown in Figure 2. However, the waste processing method may be carried out using a processing system different from the waste processing system described above.

[0063] An example of a waste treatment method may include: a first magnetic separation step of separating a first waste containing magnetic metals, non-magnetic metals, and ash into a magnetic material containing magnetic metals and a non-magnetic material containing non-magnetic metals; a separation step of separating at least a portion of the deposits, including ash, attached to the magnetic metals in the magnetic material by vibration to obtain a first metal-containing material with a higher magnetic metal content than the magnetic material; a sieving step of screening the non-magnetic material; a crushing step of crushing the sieved material obtained in the sieving step to obtain a second metal-containing material consisting of crushed material; and a second magnetic separation step of separating at least a portion of the magnetic metals contained in the first metal-containing material and the second metal-containing material to obtain a second waste with a reduced magnetic metal content compared to the first waste. The second waste thus obtained may be used as waste containing non-magnetic metals and ash, and the above-described moisture acquisition step, sorting step, and detection step may be performed. This allows for the smooth processing of large metal fragments or waste containing magnetic metals (first-class waste), separating them into magnetic metals, non-magnetic metals, and ash, and effectively utilizing them as recyclable resources and raw materials for cement production.

[0064] The processing method in this example can be carried out using the waste processing system 200 shown in Figure 3. The first magnetic separation step can be performed using the first magnetic separation device 72, the separation step using the separation device 73, the sieving step using the roll screen 74, the crushing step using the crushing device 75, the second magnetic separation step using the second magnetic separation device 76, the moisture acquisition step using the moisture meter 31, the sorting step using the eddy current separation unit 10, and the detection step using the first detection unit 34 and the second detection unit 32.

[0065] Each of the above steps can be carried out based on the descriptions in the waste treatment systems 100, 200 and their modified versions. Therefore, the descriptions in the waste treatment systems 100, 200 can also be applied to the waste treatment methods. Furthermore, the descriptions in the waste treatment methods can also be applied to the waste treatment systems.

[0066] Although embodiments of the present disclosure have been described above, the present disclosure is not limited in any way to the embodiments described above. For example, the waste treatment system does not necessarily have to include all of the moisture information acquisition unit, the first detection unit, and the second detection unit; it may have any one of them. The waste treatment method does not necessarily have to include both the moisture information acquisition step and the detection step; it may have any one of them. [Explanation of Symbols]

[0067] 10...Eddy current separation unit (separation unit), 11...Eddy current separator, 12...Belt, 13...Roller, 13A, 50A...Drive unit, 14...Magnet drum, 15...Magnet, 17...Rotating drum, 20...Waste, 21...Non-magnetic metal, 22...Ash, 30...Control unit, 31...Moisture meter, 32...Second detection unit, 34...First detection unit, 41...First sorted material, 42...Second sorted material, 50...Partition member 51...Oscillating part, 53...Oscillating shaft, 55...Support part, 60...Conveying part, 62...Vibrating feeder, 71...Receiving hopper, 72...First magnetic separator, 73...Separation device, 74...Roll screen, 75...Crushing device, 76...Second magnetic separator, 81...Roller, 82...Frame, 83...Hopper, 84...Rotating plate, 85...Rotating shaft, 100, 200...Waste processing system.

Claims

1. A moisture information acquisition unit comprising a moisture meter that acquires moisture information of waste containing nonmagnetic metals and ash using absorption in the near-infrared region, The sorting unit includes an eddy current separator that sorts the waste into at least a first sorted material containing the non-magnetic metal and a second sorted material containing the ash, A waste treatment system configured to allow adjustment of sorting conditions in the sorting section based on the aforementioned moisture information.

2. The system comprises at least one detection unit selected from the group consisting of a first detection unit for detecting ash content in the first sorted material and a second detection unit for detecting metals in the second sorted material. The waste treatment system according to claim 1, wherein the sorting conditions can be adjusted based on the detection results from the detection unit.

3. The waste treatment system according to claim 1 or 2, wherein the adjustment of the sorting conditions includes moving at least a portion of a partitioning member that separates the drop areas of the first sorted material and the second sorted material relative to the eddy current separator.

4. The eddy current separator is of the rotary magnet type, The waste treatment system according to any one of claims 1 to 3, wherein the adjustment of the sorting conditions includes changing the speed at which a belt supplying the waste onto a rotating magnetic drum moves.

5. Upstream from the aforementioned sorting section, The system includes a magnetic separation unit that separates at least a portion of the magnetic metal from a first waste containing magnetic metal, non-magnetic metal, and ash to obtain a second waste having a reduced amount of magnetic metal compared to the first waste. A waste treatment system according to any one of claims 1 to 4, wherein the second waste is used as the waste.

6. A moisture information acquisition step that acquires moisture information of waste containing non-magnetic metal and ash using a moisture meter that utilizes absorption in the near-infrared region, The process includes a sorting step in which the waste is sorted using an eddy current separator into a first sorted material containing at least the non-magnetic metal and a second sorted material containing the ash, A waste treatment method comprising adjusting sorting conditions based on the moisture information in the sorting step.

7. The system includes a detection step for detecting at least one selected from the group consisting of ash content in the first sorted material and metals in the second sorted material. The waste treatment method according to claim 6, further comprising adjusting the sorting conditions based on the detection results in the detection step.

8. The waste disposal method according to claim 6 or 7, wherein the adjustment of the sorting conditions in the sorting step includes moving at least a portion of the partitioning member separating the first sorted material and the second sorted material relative to the eddy current separator.

9. In the aforementioned sorting process, a rotating magnet type eddy current separator is used. The waste treatment method according to any one of claims 6 to 8, wherein the adjustment of the sorting conditions in the sorting step includes changing the speed at which the belt supplying the waste onto the rotating magnetic drum of the eddy current separator moves.

10. The invention includes a magnetic separation step in which at least a portion of the magnetic metal is separated from a first waste containing magnetic metal, non-magnetic metal, and ash to obtain a second waste having a reduced amount of magnetic metal compared to the first waste. A method for treating waste according to any one of claims 6 to 9, wherein the second waste is used as the waste.

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