Waste disposal methods, waste disposal equipment

Abstract

This invention provides a method that enables the efficient separation and recovery of combustible and non-combustible waste from a mixture of both, while suppressing carbon dioxide emissions. [Solution] The waste treatment method comprises the steps of: (a) supplying a heated solid heat transfer medium to a containment area physically partitioned by a wall; (b) supplying waste to be treated, which consists of a mixture of combustible waste and noncombustible waste, to the containment area; (c) heating the waste to be treated in a noncombustible manner using the sensible heat of the solid heat transfer medium to cause it to become brittle or carbonized by continuing the state in which the solid heat transfer medium and the waste to be treated are present in the containment area for a predetermined period of time; and (d) separating the waste to be treated into combustible waste and noncombustible waste after step (c).

Description

Technical Field

[0001] The present invention relates to a waste treatment method, and particularly to a treatment method for waste in which combustible waste and non-combustible waste are mixed. The present invention also relates to waste treatment equipment suitable for such treatment.

Background Art

[0002] Shredder dust discharged from the disposal of end-of-life vehicles, home appliances, and the like is a type of waste. Shredder dust often contains glass scraps and metals such as copper and aluminum that cannot be completely separated and recovered by magnetic separators or the like, in a mixture of resin, urethane, and the like. That is, shredder dust is waste in which combustible waste composed of resin, urethane and the like and non-combustible waste such as metals are mixed (hereinafter appropriately referred to as "mixed waste").

[0003] In many cases, earth and sand, glass scraps, and various metals are also mixed in combustible waste such as waste resin, waste tires, rice husks, wood chips, PKS (palm kernel shell), RDF (refuse derived fuel), and sludge. These wastes can also be said to be examples of mixed waste.

[0004] As a conventional method for treating mixed waste, a method is widely known in which combustible waste is combusted to recover thermal energy, and then non-combustible waste is recovered from the incineration residue.

[0005] The applicant of the present application has previously proposed a waste treatment method that emphasizes the recovery of non-combustible waste as a valuable material, in which combustible waste is heated and embrittled to easily recover non-combustible waste (see Patent Document 1). This method aims to effectively recycle metals and the like contained in shredder dust. The shredder dust is heat-treated at a temperature of 250°C to 400°C to be embrittled, then pulverized to a predetermined size, classified, etc., and then magnetic materials and heavy products are separated and recovered.

Prior Art Documents

Patent Documents

[0006] [Patent Document 1] Japanese Patent Publication No. 2018-34143 [Overview of the project] [Problems that the invention aims to solve]

[0007] According to Patent Document 1, it is described that shredder dust can be embrittled by heat treatment at a temperature of 250°C to 400°C using common heating furnaces such as fixed furnaces, stoker furnaces, rotary kilns, fluidized bed furnaces, vertical furnaces, and multi-stage furnaces. However, since this heating involves combustion, the heating temperature tends to become high easily, making temperature control relatively difficult.

[0008] Furthermore, the method described in Patent Document 1 involves combustion during the heating of mixed waste, which generates greenhouse gases such as carbon dioxide. Therefore, from the perspective of its impact on global warming, there is room for consideration regarding the method used for heat treatment.

[0009] In view of the above problems, the present invention aims to provide a method that enables the efficient separation and recovery of combustible and non-combustible waste from a mixture of combustible and non-combustible waste while suppressing carbon dioxide gas emissions. Furthermore, the present invention aims to provide equipment suitable for implementing such a method. [Means for solving the problem]

[0010] The waste treatment method according to the present invention comprises the steps of (a) supplying a heated solid heat transfer medium into a containment area (hereinafter referred to as "waste heating device") that is physically partitioned by a wall, (b) A step of supplying waste to be treated, which consists of a mixture of combustible waste and noncombustible waste, into the waste heating device, After steps (a) and (b), step (c) is performed, in which the state in which the solid heat transfer medium and the waste to be treated are present in the waste heating device is maintained for a predetermined time, thereby heating the waste to be treated in a non-combustion manner using the sensible heat of the solid heat transfer medium, causing it to become brittle or carbonized. The method is characterized by having a step (d) after step (c) of separating the waste to be treated into combustible waste and non-combustible waste.

[0011] In the above, "a containment area physically partitioned by a wall" refers to an area where a substantially closed space is formed, excluding an inlet for introducing a solid heat transfer medium and waste to be processed from the outside into the containment area, and an outlet for discharging the solid heat transfer medium, waste to be processed, and gases generated or expanded within the containment area from the inside to the outside. Here, "wall" refers collectively to members that partition a space, and typical examples include the walls of a casing and members that partition the space inside a casing. Note that the containment area is not limited to a casing; for example, the walls and sealing members of a pipe in a sealed space formed by sealing a part of a pipe are also included in "wall." In this case, the sealed part of the pipe corresponds to the containment area.

[0012] According to the above waste treatment method, the degree of embrittlement or carbonization of combustible waste can be easily controlled by adjusting at least one of the following: the temperature of the solid heat transfer medium, the heating time of the waste to be treated, the ratio of the waste to be treated to the solid heat transfer medium during heating, and the positional state of the waste to be treated and the solid heat transfer medium during heating. Therefore, it is possible to easily obtain mixed waste in which combustible waste has been appropriately embrittlemented or carbonized, and for example, by physically impacting and breaking the embrittlemented or carbonized combustible waste, it becomes possible to easily separate the combustible waste from the non-combustible waste.

[0013] In step (c), it is preferable to heat the temperature in the containment area to 300°C to 1,000°C from the viewpoint of moderately embrittle or carbonize the combustible waste. For this purpose, the temperature of the solid heat transfer medium supplied to the containment area in step (a) is preferably 300°C to 1,400°C. The reason why it is preferable for the temperature of the solid heat transfer medium to be 1,400°C or lower is due to the handling characteristics of the solid heat transfer medium as a high-temperature substance.

[0014] Furthermore, in step (c), from the viewpoint of moderately embrittle or carbonize the combustible waste and from the viewpoint of processing efficiency, the time for which the solid heat transfer medium and the waste to be processed are present in the containment area is preferably 30 seconds to 60 minutes, more preferably 30 seconds to 30 minutes, even more preferably 1 minute to 20 minutes, and particularly preferably 1 minute to 10 minutes.

[0015] Furthermore, since process (c) is carried out by heating using the sensible heat of a solid heat transfer medium, it does not require the supply of fuel or oxygen. As a result, the generation of carbon dioxide gas is suppressed when process (c) is executed.

[0016] The aforementioned waste to be treated is waste consisting of a mixture of combustible and noncombustible materials, and typically exists in a state where the combustible and noncombustible materials are attached or intertwined to such an extent that they cannot be easily separated. Typical examples of the aforementioned waste to be treated include shredder dust (ASR, SR) generated from the disposal of vehicles, home appliances, etc. In addition, waste resin, waste tires, rice husks, wood chips, palm kernel shells (PKS), waste-derived fuel (RDF), sludge, etc., are also included in the aforementioned waste to be treated if they contain a mixture of noncombustible materials such as soil, stone, glass scraps, and various metals.

[0017] The size of the waste to be processed is arbitrary, but considering ease of transfer into and out of the waste heating device and ease of mixing with the solid heat transfer medium within the waste heating device, it is preferable that the width is 150 mm or less, more preferably 100 mm or less, and particularly preferably 50 mm or less.

[0018] Furthermore, considering the handling properties as a high-temperature substance, its mixability with the waste to be treated, and its ability to be separated and recovered, the solid heat transfer medium preferably has an average particle size of 1 μm to 300 mm, more preferably 1 μm to 150 mm, even more preferably 1 μm to 50 mm, and particularly preferably 10 μm to 30 mm.

[0019] The solid heat transfer medium can be any material that does not decompose or break down when heated to a predetermined temperature, and does not undergo any chemical reactions with the waste to be treated. For example, one or more materials selected from the group consisting of sand, gravel, silica, limestone, calcium oxide, fly ash, slag, glass, alumina, zirconia, aluminum nitride, silicon carbide, silicon nitride, forsterite, steatite, cordierite, sialon, mullite, iron balls, steel balls, refractory metal balls, cement clinker raw materials, cement clinker dust, cement clinker, refractory bricks, and refractory brick scraps can be suitably used.

[0020] In step (c), it is sufficient that the heated solid heat transfer medium and the waste to be treated are present in the waste heating device, and the relative positions of the two within the waste heating device are arbitrary. That is, the waste to be treated and the solid heat transfer medium may be in contact with each other, or not in contact with each other, or they may be mixed together overall (mixed), or mixed in some areas (unevenly distributed), or not mixed at all (localized). Furthermore, the atmosphere in the waste heating device at the start of step (c) may be an inert gas without oxygen or a vacuum in order to suppress the combustion of combustible waste. Alternatively, a small amount of oxygen may be present, as long as it is only enough to cause some of the combustible waste to burn. Note that the definition of vacuum here conforms to that specified in JIS Z 8126-1:1999.

[0021] As described above, shredder dust typically contains combustible wastes such as resins and urethane, and non-combustible wastes such as glass scraps and metals, which are normally complexly entangled and integrated with each other. Even when the waste to be treated is a mixed waste represented by such shredder dust and the like, the step (c) heats the waste to be treated, particularly the combustible wastes contained in the waste to be treated. As a result, compared to the point of time at step (b), the combustible wastes that are in contact with the metals (non-combustible wastes) in particular are deformed and embrittled, or carbonized to reduce in volume. This makes it easy to eliminate the adhesion and entangled state of the two, and the subsequent step (d) can separate the waste to be treated into the combustible wastes and the non-combustible wastes.

[0022] Note that even if the combustible wastes and the non-combustible wastes are in an adhered or entangled state after the execution of step (c), the combustible wastes have undergone deformation, embrittlement, or volume reduction due to carbonization as described above. Therefore, under the physical action of the separation device or the like used during the execution of step (d), the adhered or entangled state between the combustible wastes and the non-combustible wastes in the waste to be treated is eliminated, and the two can be separated.

[0023] From this point of view, the waste treatment method may further include a step (e) of applying an impact to the waste to be treated obtained after the step (c), and the step (d) may be performed after the step (e).

[0024] As the step (e), typically, a step of crushing the heated waste to be treated with a crusher can be adopted. This makes it easier to eliminate the mixing of the combustible wastes and the non-combustible wastes.

[0025] The step (c) may include a step of agitating the inside of the waste heating apparatus.

[0026] This ensures that sensible heat from the heated solid heat transfer medium is uniformly transferred to the waste to be treated. The objects being agitated may be one or more of the following: the waste to be treated, the solid heat transfer medium, and the atmosphere of the waste heating device.

[0027] By the way, when mixed waste is heated using a general heating furnace such as the one mentioned in Patent Document 1 above, the combustible gas produced by the thermal decomposition of the combustible waste contained in the mixed waste is either burned on the spot or, even if it does not burn, is diluted by a large amount of supplied gas.

[0028] However, according to the above method, since no combustion operation is involved during the execution of step (c), oxygen or supplied gas is not required. This makes it possible to recover combustible gases such as carbon monoxide generated by the thermal decomposition of combustible waste contained in the waste to be treated, without combustion or dilution.

[0029] From this viewpoint, the waste treatment method may also include a step (f) of recovering the combustible gas generated by the execution of step (c) through an exhaust port provided in the waste heating device.

[0030] Step (d) may also include a step of separating the waste to be treated into combustible waste and non-combustible waste based on differences in specific gravity.

[0031] Specific examples of this method include employing wind classifiers, inertial classifiers, centrifugal classifiers, sieving devices, gravity separators, and the like.

[0032] More specifically, step (d) is: Step (d1) involves removing the mixture of the waste to be treated and the solid heat transfer medium from the waste heating device after the execution of step (c), The process includes a step (d2) in which the mixture extracted in step (d1) is separated in multiple stages based on differences in specific gravity, The process may also be a step in which the mixture is separated into the combustible waste, the noncombustible waste, and the solid heat transfer medium after the above-mentioned step (d2).

[0033] In this case, the waste treatment method further comprises a step (g) of heating the solid heat transfer medium separated in step (d2), Step (a) may also include a step of supplying the solid heat transfer medium heated in step (g) into the waste heating device.

[0034] According to this method, the total amount of solid heat transfer fluid used can be reduced, and at the same time, since the temperature of the solid heat transfer fluid after use is higher than room temperature, the thermal energy required to bring the solid heat transfer fluid to a predetermined temperature can be reduced.

[0035] Furthermore, when performing step (g), the combustible gas recovered in step (c) may be burned.

[0036] In other words, the waste treatment method includes a step (f) of recovering the combustible gas generated by the execution of step (c) through an exhaust port provided in the waste heating device, Step (g) may also be a step of heating the solid heat transfer medium separated in step (d2) by burning the combustible gas recovered in step (f).

[0037] Furthermore, the waste treatment method may also include a step (g) of supplying the solid heat transfer medium separated in step (d2) to a cement kiln together with cement clinker raw materials.

[0038] According to the above method, the recovered, used solid heat transfer fluid can be used as a raw material for cement clinker.

[0039] The waste treatment equipment according to the present invention is A waste heating device comprising a containment area physically separated by a wall, a first inlet for introducing waste to be treated, which consists of a mixture of combustible and non-combustible waste, into the containment area, and a second inlet for introducing a heated solid heat transfer medium into the containment area, wherein the waste to be treated is heated in a non-combustion manner using the sensible heat of the solid heat transfer medium, The system is characterized by comprising a separation device for separating the waste to be treated, which has been heated by the waste heating device, into combustible waste and non-combustible waste.

[0040] The waste heating device in the above-mentioned waste treatment facility can heat the waste to be treated using a non-combustion method by utilizing the sensible heat of a solid heat transfer medium. This makes it easier to adjust the heating conditions and suppresses the generation of carbon dioxide gas during heating. The first and second inlets may be separate or they may be a single unit.

[0041] The separation device may include a crusher that applies impact to the waste to be treated, which has been heated by the waste heating device, and separates the waste to be treated, after impact has been applied by the crusher, into combustible waste and non-combustible waste.

[0042] As the crushing device, a jaw crusher, impact crusher, hammer crusher, roll crusher, or other types of crushers, or a cutter mill, can be used.

[0043] The waste heating device may also have a stirring section for stirring the contents within the containment area.

[0044] As the waste heating device equipped with the stirring section, suitable options include a container-fixed mixer, a V-type mixer, a continuous container-rotating mixer such as a horizontal cylindrical mixer or a double-cone mixer.

[0045] The separation device comprises a plurality of units that separate the material to be separated in multiple stages based on differences in specific gravity, and separates the mixture of the waste to be treated after being heated by the waste heating device and the solid heat transfer medium used for heating into the combustible waste, the noncombustible waste, and the solid heat transfer medium. The waste treatment facility further comprises a heat transfer medium heating device for heating the solid heat transfer medium separated by the separation device, The solid heat transfer medium heated by the heat transfer medium heating device may be supplied to the waste heating device through the second inlet.

[0046] The unit belonging to the separation device can be one or more types belonging to the group consisting of wind classifiers, inertial classifiers, centrifugal classifiers, sieving devices, dry gravity separators, and dry fluidized bed gravity separators.

[0047] The waste heating device has an exhaust port for discharging gas from the containment area. The waste treatment facility has piping connecting the exhaust port and the heat transfer medium heating device. The aforementioned heat transfer medium heating device is The flammable gas generated by heating the waste to be processed within the waste heating device is introduced through the exhaust port via the piping. The solid heat transfer medium may be heated by burning the aforementioned flammable gas.

[0048] The heat transfer medium heating device can be a general-purpose heating furnace such as a fixed furnace, rotary furnace, stoker furnace, external heating furnace, internal combustion furnace, or fluidized bed furnace. From the viewpoint of temperature control accuracy and ease of operation, an external heating rotary kiln with multiple lifter members erected on the inner surface of the kiln is preferred.

[0049] The separation device comprises a plurality of units that separate the material to be separated in multiple stages based on differences in specific gravity, and separates the mixture of the waste to be treated after being heated by the waste heating device and the solid heat transfer medium used for heating into the combustible waste, the noncombustible waste, and the solid heat transfer medium. Of the multiple units constituting the separation device, the specific unit that performs the separation of the solid heat transfer medium may be connected to a cement kiln that fires cement clinker raw materials. [Effects of the Invention]

[0050] According to the present invention, combustible waste and non-combustible waste can be efficiently separated and recovered from a mixture of combustible and non-combustible waste while suppressing the emission of carbon dioxide gas. [Brief explanation of the drawing]

[0051] [Figure 1] This is a schematic block diagram showing the configuration of the first embodiment of the waste treatment facility. [Figure 2] This is a schematic block diagram illustrating an example of the detailed configuration of the separation device of the first embodiment. [Figure 3] Figure 1 is a schematic diagram showing the waste treatment facility connected to the cement manufacturing facility. [Figure 4] This is a schematic block diagram illustrating another example of the detailed configuration of the separation device of the first embodiment. [Figure 5] This is a schematic block diagram showing the configuration of the second embodiment of the waste treatment facility. [Figure 6] This is a schematic block diagram illustrating an example of the detailed configuration of the separation device of the second embodiment. [Figure 7] This is a schematic block diagram illustrating another example of the detailed configuration of the separation device of the second embodiment. [Modes for carrying out the invention]

[0052] Hereinafter, embodiments of the waste treatment method and waste treatment equipment according to the present invention will be described with reference to the drawings as appropriate. Note that the following drawings are all schematic illustrations.

[0053] [First Embodiment] A first embodiment of the waste treatment method and waste treatment equipment according to the present invention will be described.

[0054] Figure 1 is a schematic block diagram showing the configuration of the first embodiment of the waste treatment facility. The waste treatment facility 1 shown in Figure 1 comprises a waste heating device 2, a separation device 3, a heat transfer medium heating device 4, and a post-treatment device 11. In Figure 1, the flow of solids is shown with solid lines with arrows, and the flow of gases is shown with dashed lines with arrows. This illustration method is the same in the following drawings.

[0055] The waste heating device 2 is a device for heating the waste to be processed (hereinafter referred to as "waste to be processed W1"). The waste heating device 2 has a first inlet 71, through which the waste to be processed W1 is introduced. More specifically, the waste heating device 2 has a containment area enclosed by walls, and the waste to be processed W1 is introduced into the containment area through the first inlet 71. The process of introducing the waste to be processed W1 into the containment area of ​​the waste heating device 2 corresponds to process (b).

[0056] The waste to be processed, W1, is a mixture of combustible and non-combustible waste (mixed waste). More specifically, the combustible and non-combustible waste in W1 are intertwined and mixed to such an extent that they cannot be easily separated.

[0057] In this specification, combustible waste refers to waste consisting of organic matter, and non-combustible waste refers to waste consisting of inorganic matter. For example, resins and wood are combustible waste, while metals, ores, and glass are non-combustible waste.

[0058] Shredder dust (ASR, SR) generated from the disposal of vehicles, home appliances, etc., is a typical example of mixed waste, containing metals such as copper and aluminum that could not be separated and recovered by magnetic separators, etc., along with glass scraps, among other combustible materials such as resins and urethanes. In addition, combustible wastes such as waste resins, waste tires, rice husks, wood chips, palm kernel shells (PKS), waste-derived fuel (RDF), and sludge may also contain non-combustible waste such as soil, stone, glass scraps, and various metals, in which case they are also considered mixed waste.

[0059] The waste heating device 2 uses the sensible heat of a preheated solid heat transfer medium M2 to heat the waste to be treated W1 in a non-combustion manner, thereby embrittle or carbonize the combustible materials (combustible waste) contained in the waste to be treated W1. More specifically, the waste heating device 2 heats the waste to be treated W1 using the sensible heat of the solid heat transfer medium M2 by keeping the waste to be treated W1 and the preheated solid heat transfer medium M2 together in the containment area for a predetermined period of time. This process corresponds to process (c).

[0060] The combustible materials in the waste W1 to be treated are expected to be organic materials such as resins. When these organic materials are heated, the fixed carbon concentration increases, and they become brittle or carbonized, with some of them changing into combustible gases G1 such as methane and carbon monoxide. On the other hand, the noncombustible materials in the waste W1 to be treated are expected to be inorganic materials such as metals. When these are heated, an oxide film is formed on the surface, or some of the brittle or carbonized resin fuses to them.

[0061] The waste heating device 2 heats the waste W1 to be treated using a non-combustion method, and therefore generates almost no carbon dioxide gas.

[0062] Furthermore, when heating the waste W1 to be treated within the waste heating device 2, there is no need to introduce combustion-supporting gases or transport gases into the waste heating device 2. Therefore, combustible gases G1 such as methane and carbon monoxide, which are generated when the waste W1 to be treated is heated within the waste heating device 2, can be recovered without substantial dilution. That is, as shown in Figure 1, the waste heating device 2 may have an exhaust port 74, and the combustible gases G1 may be recovered through the exhaust port 74. This process corresponds to process (f).

[0063] The waste W1 to be processed is dried in the waste heating device 2, but from the viewpoint of improving the efficiency and stabilization of the heat treatment, it is preferable to use waste with a low moisture content. For example, it is preferable to adjust the moisture content of the waste W1 to be processed to 50% by mass or less before it is introduced into the waste heating device 2 via the first inlet 71.

[0064] The waste heating device 2 has a second inlet 72 for introducing the solid heat transfer medium M2 into the containment area. The solid heat transfer medium M2 is preferably heated to 300°C to 1,400°C in the heat transfer medium heating device 4. The heat transfer medium heating device 4 is a device that heats the solid heat transfer medium M1 before heating. The process of introducing the heated solid heat transfer medium M2 into the containment area of ​​the waste heating device 2 corresponds to process (a).

[0065] The solid heat transfer medium M1 (M2) is preferably an inorganic substance. The inorganic substance constituting the solid heat transfer medium M1 may be determined according to the type and proportion of either or both of the combustible and noncombustible materials contained in the waste W1 to be treated. Examples of inorganic substances constituting the solid heat transfer medium M1 include one or more substances belonging to the group consisting of sand, gravel, silica, limestone, calcium oxide, fly ash, slag, glass, alumina, zirconia, aluminum nitride, silicon carbide, silicon nitride, forsterite, steatite, cordierite, sialon, mullite, iron balls, steel balls, refractory metal balls, cement clinker, cement clinker dust, cement clinker raw materials, refractory bricks, and refractory brick scraps.

[0066] The introduction of the heated solid heat transfer medium M2 or the waste to be treated W1 into the waste heating device 2 may be intermittent, like batch processing, or continuous, or a combination of one being intermittent and the other continuous.

[0067] Although Figure 1 shows the first inlet 71 and the second inlet 72 as being located in different positions, it is possible to make them common. For example, by adjusting the timing of introducing the waste to be treated W1 into the containment area of ​​the waste heating device 2 and the timing of introducing the solid heat transfer medium M2 into the containment area, the first inlet 71 and the second inlet 72 can be made common.

[0068] The waste heating device 2 is preferably equipped with a thermometer 61 to monitor the temperature within the containment area. If the thermometer 61 is lower than the target temperature range, the amount and rate of introduction of the heated solid heat transfer medium M2 into the waste heating device 2 may be increased, or in addition, the heating capacity of the heat transfer medium heating device 4 may be increased to raise the temperature of the solid heat transfer medium M2. Conversely, if the thermometer 61 is higher than the target temperature range, additional waste W1 to be treated may be introduced into the waste heating device 2, the amount and rate of introduction of the solid heat transfer medium M2 may be decreased, or in addition, the heating capacity of the heat transfer medium heating device 4 may be reduced to lower the temperature of the solid heat transfer medium M2.

[0069] The mixing ratio of the waste to be treated W1 and the solid heat transfer medium M2 introduced into the containment area of ​​the waste heating device 2 is preferably such that the mass ratio per unit time is (mass of waste to be treated W1) / (mass of solid heat transfer medium M2) is 1 / 20 to 1 / 2. Within this range, the waste to be treated W1 can be heated even if the waste heating device 2 is a continuous type.

[0070] In the containment area of ​​the waste heating device 2, the time for which the waste to be treated W1 and the solid heat transfer medium M2 are kept can be adjusted as appropriate by checking the state of the resulting waste to be treated W2, so as to suppress excessive thermal decomposition of combustible materials contained in the waste to be treated W1 while drying the waste to be treated W1 and embritting or carbonizing the combustible materials. In order to stably perform the heating treatment in the continuous waste heating device 2, for example, if the temperature in the containment area of ​​the waste heating device 2 is 300°C to 1,000°C, it is preferable to set the residence time in the containment area to 30 seconds to 60 minutes. More preferably, the set temperature is 500°C to 800°C and the residence time is 30 seconds to 30 minutes.

[0071] The waste heating device 2 preferably includes an agitation unit that agitates the contents within the containment area, from the viewpoint of uniformly heating the waste W1 to be treated using the sensible heat of the solid heat transfer medium M2. The agitation unit can be of any type, regardless of the mixing mechanism, continuous or batch type. Examples of agitation units include continuous container-fixed mixers such as a Pugmill, in which multiple blades are attached to a horizontal axis and the blades rotate and move to mix as the horizontal axis is rotated; a ribbon mixer, in which ribbon blades are attached to a horizontal axis and the ribbon rotates and moves to mix as the horizontal axis is rotated; a V-type mixer that performs a three-dimensional folding action in which the contents are repeatedly gathered and separated as the container rotates; a horizontal cylindrical mixer with baffles or blades attached inside the container to improve mixing accuracy; or a continuous container-rotating mixer such as a double cone mixer.

[0072] The stirring unit may stir the atmosphere within the containment area of ​​the waste heating device 2, or it may stir the atmosphere along with one or both of the solid heat transfer medium M2 and the waste to be treated W1. The containment area of ​​the waste heating device 2 may also be a vacuum, in which case the stirring unit may preferably stir both the solid heat transfer medium M2 and the waste to be treated W1.

[0073] Within the waste heating device 2, the solid heat transfer medium M2 and the waste to be treated W1 may be mixed. In this case, it is preferable that the waste to be treated W1 has a shape that allows it to roll with few large planar surfaces within the containment area of ​​the waste heating device 2, from the viewpoint of mixing with the solid heat transfer medium M2.

[0074] Furthermore, if the waste to be treated W1 is a complex mixture of combustible and noncombustible materials, it is preferable that the solid heat transfer medium M2 penetrates into the interior of the waste to be treated W1 so that it can heat, embrittle, or carbonize the combustible materials located deep within the waste to be treated W1. From this viewpoint, the solid heat transfer medium M2 is preferably fine particles with an average particle size on the order of μm. However, if the size of the solid heat transfer medium M2 is large and there are few gaps or pores leading into the interior of the waste to be treated W1, the solid heat transfer medium M2 may be particles with an average particle size on the order of cm.

[0075] The shape of the solid heat transfer medium M2 is not particularly limited, but a spherical shape is preferred from the viewpoint of its mixability with the waste to be treated W1 in the waste heating device 2, its transferability between devices, and its separation and recovery in the subsequent separation device 3.

[0076] Hereinafter, the solid heat transfer medium M2 used in the waste heating device 2 will be referred to as "solid heat transfer medium M3". From the viewpoint of handling the solid heat transfer medium M2 and separating and recovering the solid heat transfer medium M3 from the mixture of the solid heat transfer medium M3 and the waste to be treated W1 after heating, the average particle size of the solid heat transfer medium M2 is preferably 1 μm to 300 mm, more preferably 1 μm to 150 mm, even more preferably 1 μm to 50 mm, and particularly preferably 10 μm to 30 mm.

[0077] Furthermore, with respect to the waste W1 to be processed, from the viewpoint of its mixability with the solid heat transfer medium M2 within the containment area of ​​the waste heating device 2 and its transferability between devices, it is preferable that its width be 150 mm or less, more preferably 100 mm or less, and particularly preferably 50 mm or less.

[0078] The shape of the waste W1 to be processed is not particularly limited, but in addition to the viewpoint of mixability with the solid heat transfer medium M2 in the waste heating device 2 described above, it is preferable that it has a shape that can roll with few large planar surfaces, from the viewpoint of transferability between devices.

[0079] As described above, in the heat transfer medium heating device 4, the solid heat transfer medium M1 is heated before heating, resulting in a solid heat transfer medium M2 heated to 300°C or higher. This solid heat transfer medium M2 is introduced into the waste heating device 2 via the second inlet 72. Preferably, the heat transfer medium heating device 4 is equipped with a thermometer 62, which can be used to check whether the temperature of the solid heat transfer medium M2 has been heated to a predetermined temperature. The temperature of the solid heat transfer medium M2 is controlled by adjusting the degree of heating in the heat transfer medium heating device 4 as needed.

[0080] As described above, the solid heat transfer medium M1 before heating is preferably heated to 300°C to 1,400°C by the heat transfer medium heating device 4. When the solid heat transfer medium M2 at this temperature is introduced into the waste heating device 2, the containment area of ​​the waste heating device 2 is heated to 300°C to 1,000°C, and the waste to be processed W1 present in the containment area is heated by the sensible heat of the solid heat transfer medium M2.

[0081] Examples of a heat transfer medium heating device 4 for heating the solid heat transfer medium M1 to 300°C to 1,400°C include combustion furnaces such as fixed furnaces, rotary furnaces, stoker furnaces, and fluidized bed furnaces, as well as heating furnaces such as externally heated furnaces and internally burned furnaces. From the viewpoint of accuracy of temperature control and ease of operation, an externally heated or internally burned rotary kiln with multiple lifter members erected on the inner surface of the kiln is preferred as the heat transfer medium heating device 4. Here, an internally burned rotary kiln is preferred when heating the solid heat transfer medium M1 to a high temperature of 1,000°C to 1,400°C.

[0082] In the case of an externally heated rotary kiln, in addition to being an externally heated furnace where temperature control inside the kiln is easy, the lifters continuously stir and agitate the solid heat transfer medium M1 as it moves toward the kiln outlet. As a result, a solid heat transfer medium M2 is obtained that is uniformly heated to the desired temperature.

[0083] Furthermore, if the solid heat transfer medium M1 is a cement clinker raw material, the heat transfer medium heating device 4 can be a preheater attached to the cement manufacturing equipment. In this case, the cement clinker raw material separated from the preheater is introduced into the waste heating device 2 as the solid heat transfer medium M2. In this case, from the viewpoint of handling and safety, it is preferable that the solid heat transfer medium M2 is 1,000°C or lower. The preheater is usually composed of a multi-stage cyclone. The solid heat transfer medium M2 may be separated from the cyclone from which the cement clinker raw material heated to 300°C to 1,000°C is discharged.

[0084] The waste to be treated W1 is heated by the waste heating device 2 using the sensible heat of the solid heat transfer medium M2, causing the waste to be decomposed into heated waste to be treated W2 and combustible gas G1. As described above, the heated waste to be treated W2 shows a state in which the combustible material it contains has become brittle or carbonized. Hereafter, "heated waste to be treated W2" will be appropriately abbreviated as "heated waste W2".

[0085] The heated waste W2 is a mixture of combustible waste R1, which consists of organic materials such as resins, rubbers, and biomass that have been embrittled or carbonized by heating, and non-combustible waste R2, which consists of inorganic materials such as metals, soil and stones, and glass scraps. On the surface of the non-combustible waste R2, some of the embrittlement or carbonized resins and rubbers are fused to the surface, and in the case of metals, an oxide film is formed on the surface.

[0086] The waste heating device 2 has an outlet 73 for discharging the heated waste W2 obtained. The heated waste W2 is sent to the separation device 3 via the outlet 73. At this time, the heated waste W2 is sent to the separation device 3 mixed with the solid heat transfer medium M2 (solid heat transfer medium M3) that has been used for heating in the waste heating device 2.

[0087] The separation device 3 is a device that separates heated waste W2 transferred from the waste heating device 2 into combustible waste R1 and non-combustible waste R2. More preferably, the separation device 3 separates a mixture of heated waste W2 and solid heat transfer medium M3 into combustible waste R1, non-combustible waste R2 and solid heat transfer medium M3.

[0088] From the viewpoint of improving separation accuracy, the separation device 3 may be composed of multiple groups of units with different functions and sizes.

[0089] Figure 2 is a schematic block diagram illustrating an example of the detailed configuration of the separation device 3. In the example shown in Figure 2, the separation device 3 includes a crusher 31, a first separator 32, a second separator 33, a third separator 34, and a fourth separator 35. In other words, Figure 2 illustrates an example in which the separation device 3 has five units. However, the number of units comprising the separation device 3 is arbitrary.

[0090] The crusher 31 crushes the heated waste W2 by applying impact to it, reducing its diameter to, for example, several millimeters to several tens of millimeters. As a result, combustible waste R1, such as resin or rubber, which has fused to the surface of the noncombustible waste R2 contained in the heated waste W2, is peeled off. This process corresponds to process (e). As the crusher 31, it is preferable to use crushers such as jaw crushers, impact crushers, hammer crushers, or roll crushers, or cutter mills.

[0091] A jaw crusher is a compression-type crusher in which a fixed plate fixed to a frame and a movable plate fixed to a swinging jaw face each other in a V-shape, clamping and compressing the material to be crushed, and discharging the crushed pieces downwards.

[0092] For example, if the solid heat transfer medium M2 is a cement clinker raw material, the used solid heat transfer medium M3 introduced from the waste heating device 2 to the crusher 31 has a small diameter, with a maximum particle size of about 200 μm. Therefore, in this case, the crusher 31 is primarily used to break down the heated waste W2 into combustible waste R1 and non-combustible waste R2, and to separate the combustible waste R1 that is fused to the non-combustible waste R2.

[0093] Furthermore, if the size of the waste W1 to be treated before heating is large, it is possible to pre-crush it using a crusher of the same type as the crusher 31 before introducing it to the waste heating device 2, from the viewpoint of handling the waste W1 and ensuring homogeneity and efficiency of heating the waste W1 in the waste heating device 2. In this case, the crushing treatment of the heated waste W2 can be omitted.

[0094] The crushing process in the crusher 31 eliminates any adhesion or entanglement between the combustible waste R1 and noncombustible waste R2 contained in the heated waste W2. As a result, the mixture of combustible waste R1, noncombustible waste R2, and solid heat transfer medium M3 is sent from the crusher 31 to the next unit, with the entanglement between them resolved.

[0095] The first separator 32, the second separator 33, the third separator 34, and the fourth separator 35 are each classification devices for classifying a mixture, and consist of a dry classification device or a specific gravity difference separation device.

[0096] Examples of classification devices used in dry processes include wind classifiers such as horizontal flow type, vertical flow type, and zigzag type; inertial classifiers such as linear type, curved type, louver type, elbow jet, and variable impactor; centrifugal classifiers such as cyclone classifiers, Fantongelen, Clacyclon, Dispersion, Separator, Microplex, Air Separator, Micron Separator, Microplex, AccuCut, TurboClassifier, O-SEPA, and CLASSIEL; and sieving devices such as in-plane motion type, various vibration type, tension type, forced agitation type, wind type, and vibrating air type; and one or more of these can be used.

[0097] Examples of gravity separation devices include dry gravity separators such as air tables, and dry fluidized bed gravity separators such as mixed metal separators, and one or more of these can be used.

[0098] The first separator 32 is composed of, for example, a zigzag-type wind classifier. As described above, a mixture of combustible waste R1, non-combustible waste R2, and solid heat transfer medium M3 is introduced from the crusher 31 to the first separator 32 in a state where the entanglement between them has been resolved.

[0099] In a zigzag-type wind classifier, a dry mixture to be separated is introduced from above through an upward-moving zigzag-shaped airflow passage. This repeatedly disperses particles through collision with the inner wall of the airflow passage, dispersion due to vortices created by the airflow, and density difference classification of particles due to the upward flow. By adjusting the airflow rate, low-density materials are recovered from the upper part of the airflow passage, and high-density materials are recovered from the lower part of the airflow passage.

[0100] More specifically, an inert gas G2 such as nitrogen gas is introduced from the lower part of the airflow passage of the first separator 32, which is composed of a zigzag-type wind classifier. In addition, a mixture of the aforementioned combustible waste R1, non-combustible waste R2, and solid heat transfer medium M3 is introduced from the upper part of the airflow passage.

[0101] By adjusting the airflow rate of the inert gas G2, non-combustible waste R2 (non-combustible waste R2a), which has a relatively high specific gravity, is discharged from the outlet at the bottom of the airflow passage of the first separator 32. Combustible waste R1 has a lower specific gravity than non-combustible waste R2a and is carried by the airflow of inert gas G2 and recovered from the top of the airflow passage. Some non-combustible waste R2b may also be present in the airflow of inert gas G2. Non-combustible waste R2a is typically metal.

[0102] Since the solid heat transfer medium M3 typically has a lower specific gravity than the non-combustible waste R2a, it is recovered from the top of the airflow passage along with the combustible waste R1, carried by the inert gas G2. In other words, the first separator 32 separates and recovers the non-combustible waste R2a, which has a relatively higher specific gravity, from the mixture of combustible waste R1, non-combustible waste R2, and solid heat transfer medium M3, and the remaining mixture is sent to the second separator 33 carried by the inert gas G2.

[0103] The second separator 33 is composed of, for example, a cyclone classifier. A cyclone classifier is a device that classifies a mixture using differences in specific gravity and particle size. Specifically, in a cyclone classifier, the centrifugal force generated by swirling a gas containing the particulate mixture inside a cylinder carries high-density or large-diameter particles toward the outer wall, causing them to fall along the outer wall of the cyclone classifier, while low-density or small-diameter particles are discharged with the airflow, thereby classifying the mixture.

[0104] As described above, when a mixture of combustible waste R1, a small amount of non-combustible waste R2b, and solid heat transfer medium M3 is introduced from the first separator 32, carried by the airflow of inert gas G2, into the second separator 33, which is composed of a cyclone classifier, the airflow containing this mixture forms a swirling flow within the cylinder of the cyclone classifier. As a result, the mixture of the relatively denser components of the combustible waste R1 (combustible waste R1a), the non-combustible waste R2b, and the relatively larger components of the solid heat transfer medium M3 (solid heat transfer medium M3a) falls from the second separator 33 and is sent to the third separator 34. On the other hand, the mixture of the relatively less dense components of the combustible waste R1 (combustible waste R1b) and the relatively smaller components of the solid heat transfer medium M3 (solid heat transfer medium M3b) is discharged from the top of the second separator 33 along with the airflow of inert gas G2 and is sent to the fourth separator 35.

[0105] The third separator 34 is composed of, for example, an air table. The air table is a dry specific gravity separation device that separates and sorts a mixture by vibrating an inclined porous deck back and forth from side to side and blowing air upward from the bottom of the deck. High-density particles move upward on the incline due to the vibration, while low-density particles float away from the deck surface and move downward on the incline due to the action of the rising air.

[0106] The mixture of combustible waste R1a, noncombustible waste R2b, and solid heat transfer medium M3a, introduced from the second separator 33 to the third separator 34, is classified by vibration of the air table deck. Specifically, the noncombustible waste R2b, which has a relatively higher specific gravity, moves to the upper part of the deck, while the combustible waste R1a and solid heat transfer medium M3a, which have a relatively lower specific gravity, move to the lower part of the deck. This allows for the separation and recovery of the noncombustible waste R2b from the mixture.

[0107] The combustible waste R1a and solid heat transfer medium M3a, separated by the third separator 34, are then transferred to the fourth separator 35. This transfer may be carried out using the airflow generated on the air table.

[0108] The fourth separator 35 is composed of, for example, a cyclone classifier. Compared to the second separator 33, the fourth separator 35 is a high-precision classifier designed for separating small-diameter, low-specific-gravity materials and small-diameter materials.

[0109] As described above, a mixture of combustible waste R1b and solid heat transfer medium M3b is introduced into the fourth separator 35 from the second separator 33, carried by the airflow of inert gas G2. In addition, a mixture of combustible waste R1a and solid heat transfer medium M3a is introduced from the third separator 34. In other words, a mixture of combustible waste R1 and solid heat transfer medium M3 is introduced into the fourth separator 35.

[0110] The mixture of combustible waste R1 and solid heat transfer medium M3, introduced into the fourth separator 35, which consists of a cyclone classifier, forms a swirling flow within the cylinder as it is carried by the flow of inert gas G2. At this time, the relatively high-density solid heat transfer medium M3 falls and is discharged, while the relatively low-density combustible waste R1 is discharged from the top of the fourth separator 35 along with the flow of inert gas G2. In this way, each is separated and recovered.

[0111] The solid heat transfer medium M3 recovered by the fourth separator 35 is sent to the post-treatment device 11. For example, if the solid heat transfer medium M3 is a cement clinker raw material, a cement kiln can be used as the post-treatment device 11.

[0112] Figure 3 is a schematic diagram showing the configuration in which waste treatment facility 1 is connected to cement manufacturing facility.

[0113] The cement manufacturing equipment 80 is equipped with a preheater into which cement clinker raw materials are fed from the upper stage. The preheater is composed of multiple cyclones connected in multiple stages, and in Figure 3, only cyclones 81, 82, and 83, including the lowest cyclone 83, are shown as examples. The cement clinker raw materials preheated in cyclones 81, 82, 83, etc. are fired in the cement kiln 84 to produce cement clinker. The produced cement clinker is cooled in a clinker cooler 85 and then sent to the next process.

[0114] In the example shown in Figure 3, a portion of the cement clinker raw material, preheated to 500°C to 700°C by passing through cyclone 81, is separated as heated solid heat transfer medium M2 and introduced to waste heating device 2 through piping 41. In this case, cyclone 81 and the cyclones located above it correspond to the heat transfer medium heating device 4.

[0115] In the waste heating device 2, as described above, the waste to be treated W1 and the solid heat transfer medium M2 remain in the containment area for a predetermined period of time, and the waste to be treated W1 is heated without combustion by utilizing the sensible heat of the solid heat transfer medium M2.

[0116] Subsequently, the mixture of heated waste W2, which is the waste to be processed after heating, and solid heat transfer medium M3, which is the solid heat transfer medium M2 used for heating, is sent to the separation unit 3. In the separation unit 3, the mixture is separated and recovered into combustible waste R1, non-combustible waste R2, and solid heat transfer medium M3, respectively.

[0117] The separated solid heat transfer medium M3 is sent through the piping 42 to the cement kiln 84 and fired. This allows the solid heat transfer medium M3 to be used as a raw material for cement clinker. In this case, the cement kiln 84 corresponds to the post-treatment device 11. By chuteting the piping 42, the solid heat transfer medium M3 can be introduced into the cement kiln 84 using potential energy. The process of supplying the separated solid heat transfer medium M3 to the cement kiln 84 corresponds to process (g).

[0118] Figure 4 is a schematic block diagram showing another example of the detailed configuration of the separation device 3. The separation device 3 shown in Figure 4 differs from the separation device 3 shown in Figure 2 in that it is additionally equipped with a fifth separator 36.

[0119] The fifth separator 36 is a magnetic separation device that separates a mixture based on the presence or absence of magnetism. Examples of magnetic separation devices include weak magnetic field type and strong magnetic field type static magnetic separation devices, as well as moving magnetic field type, oscillating magnetic field type, and electromagnetic induction type AC magnetic separation devices.

[0120] When a mixture of combustible waste R1, noncombustible waste R2, and solid heat transfer medium M3 is introduced into the fifth separator 36, only the magnetic noncombustible waste R2c is separated and recovered from the mixture. The remaining mixture is sent to the subsequent first separator 32. In Figure 4, the noncombustible waste that does not possess magnetism is denoted by the symbol R2d.

[0121] This configuration allows for the efficient recovery of iron contained in the waste W1 to be processed. From this perspective, the fifth separator 36 may be placed downstream of either the first separator 32 or the third separator 34, or both.

[0122] Note that the configuration of the separation device 3 described above with reference to Figure 2 is merely an example. The configuration of the separation device 3 can be appropriately selected as long as it is possible to separate and recover each component from the mixture of combustible waste R1, noncombustible waste R2, and solid heat transfer medium M3. However, from the viewpoint of improving separation performance, it is preferable that the separation device 3 be equipped with multiple units to separate the mixture in multiple stages. The same applies to the following embodiments.

[0123] [Second Embodiment] A second embodiment of the waste treatment method and waste treatment equipment according to the present invention will now be described. In the following, explanations of aspects common to the first embodiment will be omitted as appropriate.

[0124] Figure 5 is a schematic block diagram showing the configuration of the second embodiment of the waste treatment equipment. Figure 6 is a schematic block diagram showing the configuration of the separation device 3 of this embodiment, following Figure 2. The waste treatment equipment 1 of this embodiment differs from the waste treatment equipment 1 of the first embodiment in that the used solid heat transfer medium M3 recovered from the separation device 3 is reheated in the heat transfer medium heating device 4. For this reason, compared to Figure 1, the waste treatment equipment 1 of this embodiment shown in Figure 5 does not have a post-treatment device 11. The step of reheating the used solid heat transfer medium M3 in the heat transfer medium heating device 4 corresponds to step (g).

[0125] The solid heat transfer medium M3 recovered by the separation device 3 is transported to the heat transfer medium heating device 4 using any transport device such as a belt conveyor. In this case, the transport device may have heat resistance that can withstand the temperature of the solid heat transfer medium M3.

[0126] As another example, the unit that separates and recovers the solid heat transfer medium M3 (the fourth separator 35 in the example of Figure 6) may be positioned vertically above the heat transfer medium heating device 4, thereby utilizing potential energy to transport the solid heat transfer medium M3 to the heat transfer medium heating device 4.

[0127] In this case, as shown in Figures 5 and 6, the combustible gas G1 recovered from the exhaust port 74 of the waste heating device 2 may be introduced into the heat transfer medium heating device 4 and used as fuel gas. This reduces the amount of fuel used to heat the solid heat transfer mediums (M1, M3).

[0128] This is also true in the first embodiment; that is, in Figure 1, some or all of the fuel used to heat the solid heat transfer medium M1 in the heat transfer medium heating device 4 may be supplied by the combustible gas G1 recovered from the exhaust port 74 of the waste heating device 2.

[0129] In this embodiment as well, similar to the first embodiment described with reference to Figure 4, the separation device 3 may be equipped with a fifth separator 36 (see Figure 7). [Examples]

[0130] The waste treatment method according to the present invention will be specifically described below with reference to examples, but the present invention is not limited to the following examples.

[0131] In this embodiment, the configurations of the waste to be treated W1 and the waste treatment facility 1 are as follows:

[0132] • Waste to be processed W1: Automotive shredder dust (hereinafter referred to as "ASR") crushed in a hammer crusher with a 50mm screen, where approximately 70% by mass consists of particles with a diameter of 5mm or less. • Solid heat transfer medium M1: Cement clinker raw material (particle size 200 μm or less, moisture content 0% by mass) • Heat transfer medium heating device 4: Preheater for rotary kiln for cement clinker production • Waste heating device 2: Pugmill type mixer • Separation device 3: A group of units consisting of a hammer crusher, magnetic separator, circulating air separator, air table, and cyclone classifier.

[0133] The solid heat transfer medium M2 was obtained by taking cement clinker raw material at a temperature of 600°C to 700°C from the third cyclone from the bottom of a multi-stage preheater installed in a cement kiln. The mass of the solid heat transfer medium M2 was set to 150 kg for 50 kg of ASR, which was the waste W1 to be treated.

[0134] The mixture of 50 kg of ASR and 150 kg of cement clinker raw material was surrounded by insulating material and stirred and mixed for 7.5 minutes using a Pugmill-type mixer, which heated and maintained the outside of the mixer section with 400°C hot air. This heated the ASR using the sensible heat of the cement clinker raw material. The reason for supplying hot air to the mixer was to simulate the fact that if the waste to be treated W1 were to be continuously heated, the temperature of the waste heating device 2 would be expected to be maintained at a certain high temperature. During the mixing of the ASR and cement clinker raw material, the supply of hot air to the mixer section was stopped.

[0135] The mixture of heated ASR and cement clinker raw materials was introduced into a hammer crusher with a 50mm screen and crushed. The recovered amount was 193kg. The remaining 7kg was determined to be water in the vaporized ASR and resins contained in the ASR that vaporized due to thermal decomposition. The hammer crusher corresponds to crusher 31.

[0136] Next, 193 kg of the mixture of heated ASR and cement clinker raw materials was introduced into a magnetic separator to separate and recover the magnetically deposited material equivalent to non-combustible waste. The recovered amount was 2 kg. The magnetic separator corresponds to the fifth separator 36.

[0137] Next, 191 kg of the mixture of heated ASR (Autoclaved Surfactant Resin) and cement clinker raw material, from which the magnetic deposits had been separated and recovered, was introduced into a circulating air separator to separate and recover the mixture of the lightweight portion (partially) corresponding to combustible waste (heat-embrittle or carbonized resin, etc.) and the cement clinker raw material (partially). The recovered amount was 168 kg. The circulating air separator corresponds to the second separator 33.

[0138] From the 168 kg of separated and recovered material (a mixture of lightweight material and cement clinker raw materials) mentioned above, 100 kg was set aside for cement clinker production.

[0139] Next, the remaining 68 kg of the separated and recovered material (a mixture of the lightweight portion and cement clinker raw material) and the 23 kg recovered as the heavy portion by the circulating air separator were introduced into an air table to separate and recover non-magnetic metals (aluminum and precious metals) corresponding to non-combustible waste. The amount recovered was 2.5 kg. The air table corresponds to the third separator 34.

[0140] Next, 88.5 kg of a mixture consisting of a mixture of heated ASR (amount of solid waste material) from which non-magnetic metals had been separated and recovered, and cement clinker raw material (first mixture), and a mixture of the lightweight portion separated and recovered by a circulating air separator and cement clinker raw material (second mixture), was introduced into a cyclone classifier to separate and recover the lightweight portion corresponding to combustible waste and the heavy portion corresponding to cement clinker raw material. The amount of combustible waste recovered was 18.5 kg, and the amount of cement clinker raw material recovered was 70 kg. The cyclone classifier corresponds to the fourth separator 35.

[0141] Tables 1 and 2 show the amounts of ASR components and solid heat transfer fluid separated in each of the above processes.

[0142] [Table 1]

[0143] [Table 2]

[0144] As mentioned above, the 68 kg mixture of solid heat transfer medium M3 (cement clinker raw material) and combustible waste R1 introduced at the start of Table 2 is the remaining 100 kg portion set aside for cement clinker production from the 168 kg mixture of solid heat transfer medium M3 and combustible waste R1 separated and recovered by the air separation device in Table 1.

[0145] Of the 168 kg mixture of solid heat transfer medium M3 and combustible waste R1 separated and recovered by a circulating air separator, 100 kg was set aside for cement clinker production. When this mixture was calcined as a raw material, the combustible waste R1 (lightweight portion) contained in the mixture was burned away, and cement clinker was calcined without any problems. Furthermore, no metal particles or other materials derived from ASR were found in the cement clinker.

[0146] Furthermore, visual inspection of the 18.5 kg lightweight portion separated and recovered by the cyclone classifier confirmed the absence of ASR-derived metals and cement clinker raw materials. [Explanation of Symbols]

[0147] 1: Waste disposal facilities 2: Waste heating device 3: Separation device 4: Heat medium heating device 11: Post-processing equipment 31: Crusher 32:First separator 33:Second separator 34:Third separator 35:Fourth separator 36:Fifth separator 41: Piping 42: Piping 61: Thermometer 62:Thermometer 71: First Inlet 72:Second introduction port 73: Outlet 74: Exhaust vent 80: Cement manufacturing equipment 81: Cyclone 82: Cyclone 83: Cyclone 84: Cement Kiln 85: Clinka Cooler

Claims

1. (a) A step of supplying a heated solid heat transfer medium into a containment area physically partitioned by a wall, (b) A step of supplying waste to be treated, which consists of a mixture of combustible waste and noncombustible waste, into the aforementioned containment area, After steps (a) and (b), step (c) is performed, in which the solid heat transfer medium and the waste to be treated are kept in the containment area for a predetermined period of time, thereby heating the waste to be treated in a non-combustion manner using the sensible heat of the solid heat transfer medium, causing it to become brittle or carbonized. A waste treatment method characterized by comprising, after step (c), a step (d) of separating the waste to be treated into combustible waste and non-combustible waste.

2. The process includes step (e) of applying an impact to the waste to be processed obtained after step (c), The waste disposal method according to claim 1, characterized in that step (d) is performed after step (e).

3. The waste treatment method according to claim 1 or 2, characterized in that step (c) includes a step of stirring the contents of the containment area.

4. A waste disposal method according to claim 1 or 2, characterized by having a step (f) of recovering the combustible gas generated by the execution of step (c) through an exhaust port provided in the containment area.

5. The waste treatment method according to claim 1 or 2, characterized in that the temperature of the solid heat transfer medium supplied into the containment area in step (a) is 300°C to 1,400°C.

6. The waste treatment method according to claim 1 or 2, characterized in that the solid heat transfer medium supplied into the containment area in step (a) is one or more selected from the group consisting of sand, gravel, silica, limestone, calcium oxide, fly ash, slag, glass, alumina, zirconia, aluminum nitride, silicon carbide, silicon nitride, forsterite, steatite, cordierite, sialon, mullite, iron balls, steel balls, refractory metal balls, cement clinker raw materials, cement clinker dust, cement clinker, refractory bricks, and refractory brick scraps.

7. The waste treatment method according to claim 1 or 2, characterized in that step (d) includes a step of separating the waste to be treated into combustible waste and non-combustible waste based on differences in specific gravity.

8. The aforementioned step (d) is, Step (d1) after the execution of step (c), the step of removing the mixture of the waste to be treated and the solid heat transfer medium to the outside of the containment area, The process includes a step (d2) of separating the mixture extracted in step (d1) in multiple stages based on differences in specific gravity, The waste treatment method according to claim 7, characterized in that, after the above step (d2), the mixture is separated into the combustible waste, the noncombustible waste, and the solid heat transfer medium.

9. The process includes a step (g) of heating the solid heat transfer medium separated in step (d2), The waste treatment method according to claim 8, characterized in that step (a) includes a step of supplying the solid heat transfer medium heated in step (g) into the containment area.

10. The process includes step (f) of recovering the flammable gas generated by the execution of step (c) through an exhaust port provided in the containment area, The waste treatment method according to claim 9, characterized in that step (g) is a step of heating the solid heat transfer medium separated in step (d2) by burning the combustible gas recovered in step (f).

11. The waste treatment method according to claim 8, further comprising step (g) of supplying the solid heat transfer medium separated in step (d2) to a cement kiln together with cement clinker raw materials.

12. A waste heating device comprising a walled containment area, a first inlet for introducing waste to be treated, which consists of a mixture of combustible and noncombustible waste, into the containment area, and a second inlet for introducing a heated solid heat transfer medium into the containment area, wherein the waste to be treated is heated in a non-combustion manner using the sensible heat of the solid heat transfer medium, A waste treatment facility characterized by comprising a separation device for separating the waste to be treated, which has been heated by the waste heating device, into combustible waste and non-combustible waste.

13. The waste treatment facility according to claim 12, wherein the separation device includes a crusher that applies impact to the waste to be treated heated by the waste heating device, and the waste to be treated after being subjected to impact by the crusher is separated into combustible waste and non-combustible waste.

14. The waste treatment equipment according to claim 12 or 13, characterized in that the waste heating device has a stirring section for stirring the contents of the containment area.

15. The separation device comprises multiple units that separate the material to be separated in multiple stages based on differences in specific gravity, and separates the mixture of the waste to be treated after heating in the waste heating device and the solid heat transfer medium used for heating into the combustible waste, the noncombustible waste, and the solid heat transfer medium. The waste treatment facility further comprises a heat transfer medium heating device for heating the solid heat transfer medium separated by the separation device, The waste treatment equipment according to claim 12 or 13, characterized in that the solid heat transfer medium heated by the heat transfer medium heating device is supplied to the waste heating device through the second inlet.

16. The waste heating device has an exhaust port for discharging gas from the containment area. The waste treatment facility has piping connecting the exhaust port and the heat transfer medium heating device. The aforementioned heat transfer medium heating device is The flammable gas generated by heating the waste to be processed within the waste heating device is introduced through the exhaust port via the piping. The waste treatment equipment according to claim 15, characterized in that the solid heat transfer medium is heated by burning the flammable gas.

17. The separation device comprises multiple units that separate the material to be separated in multiple stages based on differences in specific gravity, and separates the mixture of the waste to be treated after heating in the waste heating device and the solid heat transfer medium used for heating into the combustible waste, the noncombustible waste, and the solid heat transfer medium. The waste treatment equipment according to claim 12 or 13, characterized in that, among the plurality of units constituting the separation device, a specific unit that performs the separation of the solid heat transfer medium is connected to a cement kiln that fires cement clinker raw materials.

Images