JP2020152828A - Solid fuel manufacturing method and usage method, and solid fuel manufacturing equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a solid fuel production apparatus capable of easily producing a solid fuel having excellent combustibility from waste containing plastic. SOLUTION: A solid fuel manufacturing apparatus 100 includes a processing unit 60 for cooling a waste containing plastic to −20 ° C. or lower using a cooling material and pulverizing the waste to obtain a pulverized product. The processing unit 60 has a cooling unit 20 that cools the waste using a coolant, and a crushing unit 30 that crushes the cooled waste to obtain a pulverized product. [Selection diagram] Fig. 1

Description

The present disclosure relates to a method for producing and using a solid fuel, and an apparatus for producing a solid fuel.

Wastes such as waste plastics and sludge are effectively used as raw materials and fuels for cement production. Such waste is put into, for example, a kiln burner of a cement kiln, a preheater, or the like for treatment. Since the flammability of waste plastic differs depending on the components contained therein, it may affect the treatment process such as cement production in some cases. For example, when solid fuel containing carbon fiber reinforced plastic (CFRP) is put into a kiln burner, the collection efficiency of a dust collector that collects soot in the exhaust gas of cement kiln may decrease.

Therefore, Patent Document 1 proposes to pulverize the waste plastic to a predetermined particle size or less before introducing the waste plastic containing carbon fibers into the cement kiln. By pulverizing in this way, the stability of waste treatment in the cement manufacturing apparatus is improved.

Japanese Unexamined Patent Publication No. 2007-131463

Plastics are used for various purposes in order to reduce the weight and improve the performance of vehicles and electronic devices. Along with this, the types and sizes of plastics are wide-ranging, and they are also compounded with other materials. Therefore, when trying to crush such waste containing waste plastic, the load on the crusher becomes large. Further, if the ratio of the thermoplastic plastic contained in the waste becomes large, there is a concern that even if a normal mill is used, the waste plastic is only deformed and cannot be sufficiently pulverized, resulting in impaired combustibility.

Therefore, the present disclosure provides a solid fuel production method capable of easily producing a solid fuel having excellent flammability from waste containing plastic, and a solid fuel production apparatus. Further, the present invention provides a method for using a solid fuel which is easily produced from waste containing plastic and uses a solid fuel having excellent flammability.

The method for producing a solid fuel according to one aspect of the present disclosure includes a treatment step of cooling a waste containing plastic to −20 ° C. or lower using a coolant and pulverizing the waste to obtain a pulverized product.

In the above manufacturing method, waste containing plastic is cooled to −20 ° C. or lower using a coolant. Therefore, at least a part of the plastic contained in the waste is embrittled, and the pulverizability can be improved. Therefore, even if the waste contains a plastic that is difficult to crush, for example, a thermoplastic, the waste can be sufficiently crushed. Therefore, the waste is finely crushed to reduce the unburned residue, and a solid fuel having excellent combustibility can be obtained. In this production method, the pulverizability is improved by cooling with a coolant, so that a solid fuel having excellent combustibility can be easily produced.

In the above production method, it is preferable to cool the waste to a temperature lower than −50 ° C. and higher than −100 ° C. and pulverize it. As a result, it is possible to sufficiently embrittle various plastics to maintain good pulverizability, suppress excessive cooling, and reduce the burden on equipment.

The coolant preferably contains a liquefied or solidified inert gas. Further, it is preferable to carry out pulverization in an atmosphere of an inert gas. As a result, ignition due to friction is sufficiently suppressed, and cooling and crushing can be performed with high safety.

The treatment step may include a cooling step of cooling the waste with a coolant and a crushing step of crushing the cooled waste to obtain a crushed product. It is preferable that the coolant used in the cooling step or a coolant different from the coolant used in the cooling step is introduced into the crushing step. In the crushing process, when the waste is crushed, the temperature may rise due to friction or the like. Therefore, by introducing the coolant used in the cooling step or another coolant, the temperature rise in the crushing step can be suppressed and the crushing can be performed more smoothly.

The waste may contain carbon fiber reinforced plastic. With the above manufacturing method, even waste containing carbon fiber reinforced plastic can be smoothly crushed. In particular, even if the carbon fiber reinforced plastic contains a thermoplastic, a solid fuel having excellent combustibility can be easily produced without impairing good pulverizability.

The manufacturing method is based on at least one index selected from the group consisting of the size of the waste, the content of carbon fibers contained in the waste, and the size of the carbon fibers contained in the waste before the treatment step. Therefore, it is preferable to have a separation step of separating the waste into a plurality of pieces, and in the treatment step, it is preferable to cool and pulverize at least one waste separated in the separation step. As a result, waste that can be crushed without cooling can be directly converted into solid fuel without cooling. Therefore, solid fuel can be efficiently produced.

It is preferable to have a recovery step of classifying the crushed product, recovering a part of the crushed product according to the size of the crushed product, and supplying it to the processing step. For example, by recovering a pulverized product having a size larger than the average size and reprocessing it in the processing step, the uniformity of the size of the solid fuel can be improved and the combustibility of the solid fuel can be further improved. ..

The coolant preferably contains at least one of liquid nitrogen and dry ice. This makes it possible to sufficiently brittle the plastic and improve the pulverizability of waste while reducing the cooling cost. In addition, it is possible to improve safety by suppressing ignition and the like during crushing.

The solid fuel manufacturing apparatus according to one aspect of the present disclosure includes a processing unit for cooling waste containing plastic to −20 ° C. or lower using a coolant and pulverizing the waste to obtain a pulverized product.

In the above manufacturing apparatus, waste containing plastic is cooled to −20 ° C. or lower by using a coolant in the processing unit. Therefore, at least a part of the plastic contained in the waste is embrittled, and the pulverizability can be improved. Therefore, even if the waste contains a plastic that is difficult to crush, for example, a thermoplastic, the waste can be sufficiently crushed. Therefore, the waste is finely crushed to reduce the unburned residue, and a solid fuel having excellent combustibility can be obtained. Since this manufacturing apparatus improves the pulverizability by cooling with a coolant, it is possible to easily manufacture a solid fuel having excellent combustibility.

In the above-mentioned manufacturing apparatus, it is preferable that the waste is cooled to a temperature lower than −50 ° C. and higher than −100 ° C. and pulverized. As a result, it is possible to sufficiently embrittle various plastics to maintain good pulverizability, suppress excessive cooling, and reduce the burden on equipment.

The processing unit may have a cooling unit that cools the waste using a coolant, and a crushing unit that crushes the cooled waste to obtain a pulverized product. In this case, it is preferable that the crushing section has a flow path for introducing a coolant via the cooling section or a coolant different from the coolant used in the cooling section. In the crushed part, when the waste is crushed, the temperature may rise due to friction or the like. Therefore, by introducing the coolant used in the cooling unit or another coolant, the temperature rise in the crushing unit can be suppressed and the pulverization can be performed more smoothly.

The waste may contain carbon fiber reinforced plastic. With the above manufacturing equipment, even waste containing carbon fiber reinforced plastic can be smoothly crushed. In particular, even if the carbon fiber reinforced plastic contains a thermoplastic, a solid fuel having excellent combustibility can be easily produced without impairing good pulverizability.

Waste on the upstream side of the treatment unit based on at least one index selected from the group consisting of the size of the waste, the content of carbon fibers contained in the waste, and the size of the carbon fibers contained in the waste. It is preferable to have a sorting unit for separating a plurality of wastes, and the processing unit preferably cools and pulverizes at least one waste separated by the sorting unit. As a result, waste that can be crushed without cooling can be directly converted into solid fuel without cooling. Therefore, solid fuel can be efficiently produced.

It is preferable to provide a recovery unit that classifies the crushed product, recovers a part of the crushed product according to the size of the crushed product, and supplies it to the processing unit. For example, by recovering a pulverized product having a size larger than the average size and reprocessing it in the processing unit, the uniformity of the size of the solid fuel can be improved and the combustibility of the solid fuel can be further improved. ..

The coolant preferably contains at least one of liquid nitrogen and dry ice. This makes it possible to sufficiently brittle the plastic and improve the pulverizability of waste while reducing the cooling cost.

The method of using the solid fuel according to one aspect of the present disclosure includes a step of burning the solid fuel obtained by the above-mentioned production method in a kiln or a calcining furnace of a cement production facility. According to this usage method, a solid fuel which is easily produced from waste containing plastic and has excellent combustibility can be burned in a kiln or a calcining furnace of a cement production facility.

According to the present disclosure, there is provided a method for producing a solid fuel capable of easily producing a solid fuel having excellent combustibility from waste containing plastic, and an apparatus for producing the solid fuel. Further, it is possible to provide a method of using a solid fuel which is easily produced from waste containing plastic and uses a solid fuel having excellent flammability.

It is a figure which shows one Embodiment of the solid fuel production apparatus. It is a figure which shows another embodiment of the solid fuel production apparatus. It is a figure which shows an example of a sorting part. It is a figure which shows another example of a sorting part.

Hereinafter, embodiments of the present disclosure will be described with reference to the drawings in some cases. However, the following embodiments are examples for explaining the present disclosure, and are not intended to limit the present disclosure to the following contents. In the description, the same reference numerals are used for the same elements or elements having the same function, and duplicate description may be omitted in some cases. Further, the positional relationship such as up, down, left and right shall be based on the positional relationship shown in the drawings unless otherwise specified. Further, the dimensional ratio of each element is not limited to the ratio shown in the figure.

The method for producing a solid fuel according to one embodiment includes a treatment step of cooling a waste containing plastic to −20 ° C. or lower using a coolant and pulverizing the waste to obtain a pulverized product. For example, the embrittlement temperature of polypropylene, which is a general-purpose plastic, is about -20 to 0 ° C, and the embrittlement temperature of achlorinitrile-butadiene-styrene resin (ABS), which is often used for interior and exterior parts of automobiles, is about -20 ° C. Is. Therefore, pulverization can be facilitated by cooling the waste containing plastic to −20 ° C. or lower. The cooling temperature of the waste may be lower than −50 ° C. and lower than −60 ° C. from the viewpoint of sufficiently embrittlement of other plastics. The cooling temperature of the waste may be a temperature higher than −100 ° C. or higher than −90 ° C. from the viewpoint of reducing the burden on the equipment.

The coolant may contain a liquefied product of the inert gas or a solidified product thereof from the viewpoint of enhancing safety. If crushing is performed in an atmosphere of an inert gas generated from such a coolant, the safety at the time of crushing can be enhanced. Examples of the liquefied product of the inert gas or the solidified product thereof include liquid nitrogen, liquid argon, and dry ice. The coolant may be liquid nitrogen or a freezing bath which is a mixture of dry ice and alcohol from the viewpoint of availability and cost.

The treatment step may separately include a cooling step of cooling the waste with a coolant and a crushing step of crushing the cooled waste to obtain a pulverized product. Further, in the treatment step, the waste may be pulverized while being cooled.

When having a crushing step, the coolant used in the cooling step may be used in the crushing step. The "coolant used in the cooling process" as used herein refers to a material used as a coolant for waste in the cooling process. Therefore, it may be derived from the coolant. For example, when liquid nitrogen is used as a coolant for waste, the nitrogen gas generated by vaporizing this liquid nitrogen also corresponds to the “coolant used in the cooling step”. The coolant used in the cooling step may be introduced into the grinding step as a liquid, solid, gas or a mixture thereof. However, the coolant used in the cooling step introduced in the pulverization step is preferably a liquid or a gas. This is because if it is a solid, there is a concern that the pulverization efficiency will decrease and that it will be mixed into the solid fuel.

A coolant other than the coolant used in the cooling step may be introduced into the pulverization step. The term "another coolant" as used herein refers to a coolant that has not passed through the cooling process and is distinguished from the coolant used in the cooling process. The types of "coolant" and "another coolant" used in the cooling step may be the same or different. By introducing the coolant into the pulverization step in this way, it is possible to sufficiently suppress the temperature rise of the waste due to friction and the like, and pulverize more smoothly. The waste may be pre-cooled in the cooling step and crushed while being cooled to a lower temperature in the crushing step. Moreover, the inert gas obtained from the coolant used in the cooling step may be introduced into the pulverization step. Thereby, pulverizability and safety can be further improved. The "other coolant" introduced into the pulverization step is also preferably a liquid or gas. This is because if it is a solid, there is a concern that the pulverization efficiency will decrease and that it will be mixed into the solid fuel.

The plastic contained in the waste is not particularly limited, and may be a thermoplastic such as polyethylene, polypropylene or polystyrene, or a thermocurable plastic such as a phenol resin or an epoxy resin. Although the thermoplastic has a tendency to be difficult to crush at room temperature, in the present embodiment, since the waste is cooled, the waste can be finely crushed even if the waste contains the thermoplastic. As a result, the unburned residue during combustion is reduced, and a solid fuel having excellent combustibility can be obtained.

The waste may contain carbon fiber reinforced plastic (CFRP). Generally, carbon fiber reinforced plastic has high strength and tends to be difficult to crush, but the production method of the present embodiment can be smoothly crushed. In particular, even if the carbon fiber reinforced plastic contains a thermoplastic, a solid fuel having excellent combustibility can be easily produced without impairing good pulverizability. The plastic contained in the carbon fiber reinforced plastic may be a thermoplastic or a thermosetting plastic. Examples of the carbon fiber include those produced by carbonizing acrylic fiber or pitch as a raw material at a high temperature. However, the carbon fiber reinforced plastic may contain components other than those described above.

The waste may be derived from daily necessities, personal computers, home appliances, automobiles, aircraft, sports equipment, construction and civil engineering fields, and the like. These wastes may be shredder dust generated by the disposal of automobiles, home appliances, and the like. The waste may include not only carbon fiber reinforced plastics but also carbon fiber-free plastics. The waste may contain foreign substances such as metal and rubber in addition to carbon fibers and resin components.

In the pulverization step, the waste cooled in the cooling step is pulverized to obtain a pulverized product. Since the plastic is embrittled in the cooling process, the waste is smoothly crushed in the crushing process. The pulverized product obtained here can be used as a solid fuel. The solid fuel may contain a pulverized product and may contain a substance other than the pulverized product.

Even if the waste contains carbon fiber reinforced plastic, the carbon fiber becomes smaller by crushing the waste, and the unburned residue when used as a solid fuel can be reduced. This improves flammability. In addition, it is possible to suppress the introduction of unburned carbon fiber residue into the electrostatic precipitator that processes the combustion gas of solid fuel, and reduce the frequency of equipment maintenance.

The size of the pulverized product (solid fuel) is not particularly limited, and may be, for example, 10 mm or less, or 5 mm or less. The crushing step may be performed using, for example, a vertical mill or a coal crushing mill. By using a vertical mill, the pulverization step and the recovery step may be performed in parallel.

In the recovery step, the crushed product is classified and a part of the crushed product is recovered according to the size of the crushed product. For example, when the plastic is not sufficiently embrittled and a coarse substance that is not pulverized to a sufficiently small size remains in the pulverization step, it is preferable to classify the pulverized substance and recover the coarse substance. The classification may be performed by a classifying machine or by a vertical mill having both a crushing function and a classifying function.

The coarse matter recovered in the recovery step may be supplied to a cooling step (processing step) and recooled. This further embrittles the plastic and makes it easier to grind. By having such a recovery step, it is possible to suppress the inclusion of coarse substances in the solid fuel. The pulverized product from which the coarse matter has been removed may be burned as a solid fuel having excellent flammability in a kiln or a calcining furnace of a cement manufacturing facility. By performing such a combustion process, waste containing plastic can be sufficiently effectively used as fuel. At least a part of the coarse matter recovered in the recovery step may be used for another purpose without returning to the cooling step (treatment step).

According to the above production method, a solid fuel having excellent combustibility can be easily produced from waste containing plastic. Further, since the solid fuel can be produced without heat-treating the waste containing plastic, it is excellent in safety and can reduce the loss of heat quantity.

The manufacturing method may be performed using, for example, the manufacturing apparatus 100 shown in FIG. In the manufacturing apparatus 100 of FIG. 1, the waste containing plastic is cooled to −20 ° C. or lower using a coolant and crushed to obtain a crushed product, and the crushed product is classified into the size of the crushed product. A recovery unit 40 is provided which collects a part of the crushed product according to the above and supplies it to the processing unit 60. The cooling temperature of the waste may be lower than −50 ° C. or lower than −60 ° C. from the viewpoint of sufficiently embrittlement of the plastic. The cooling temperature of the waste may be higher than −100 ° C. or higher than −90 ° C. from the viewpoint of reducing the burden on the equipment.

The processing unit 60 includes a cooling unit 20 that cools the waste using a coolant, and a crushing unit 30 that crushes the cooled waste to obtain a pulverized product. Waste and coolant are supplied to the cooling unit 20. The cooling unit 20 may perform the above-mentioned cooling step. As the coolant, a liquefied or solidified inert gas may be used. The coolant introduced into the cooling unit 20 may be vaporized or liquefied by heat exchange with the waste. The inert gas obtained by vaporization or a liquefied product thereof may be introduced into the pulverizing section 30 via the flow path 25. Thereby, the safety in the crushing unit 30 can be improved.

In the crushing unit 30, the above-mentioned crushing step may be performed. Further, the crushing unit 30 may be used as a vertical mill, for example, to crush the lumpy material and classify the crushed material in parallel. A coolant different from the coolant used in the cooling unit 20 may be introduced into the crushing unit 30. Another coolant is introduced directly into the crushing section 30 by the flow path 32 without passing through the cooling section 20 and the flow path 25. The type of the coolant introduced into the cooling unit 20 and the type of the coolant introduced into the crushing unit 30 may be the same or different.

The classification unit 42 in the collection unit 40 classifies the crushed product and classifies the crushed product into two or more according to the size. The crushed material larger than the predetermined size is conveyed by the conveying unit 44 and returned to the cooling unit 20. By having such a recovery unit 40, the large-sized crushed material is recooled by the cooling unit 20 and re-crushed by the crushing unit 30. As a result, it is possible to suppress the mixing of coarse substances into the pulverized product, and further improve the combustibility of the solid fuel. By using a vertical mill as the rating unit 42, the crushing unit 30 and the rating unit 42 may be integrated.

The description of each step in the above manufacturing method can be applied to each component of the manufacturing apparatus 100. The manufacturing apparatus 100 can easily manufacture a solid fuel having excellent combustibility even if it is a waste containing carbon fiber reinforced plastic.

In another embodiment, before the treatment step (cooling step), at least selected from the group consisting of the size of the waste, the content of carbon fibers contained in the waste, and the size of the carbon fibers contained in the waste. It has a step of separating waste into a plurality of wastes based on one index. If the size of the waste is used as an index for sorting, the small waste that requires no or almost no crushing can be crushed or made into a solid fuel as it is without cooling. Therefore, the amount of coolant used can be suppressed and the production cost of solid fuel can be reduced.

If the carbon fiber content in the waste or the size of the carbon fiber in the waste is used as an index, the waste containing a large amount of carbon fiber that is difficult to crush and the waste containing a large carbon fiber can be treated. It is possible to avoid being processed by. As a result, the operating cost and the equipment burden can be reduced. Wastes containing carbon fibers that are not treated in the treatment step may be used for other purposes.

The manufacturing method according to the other embodiment may be performed using, for example, the manufacturing apparatus 101 of FIG. The manufacturing apparatus 101 of FIG. 2 uses a cooling material to separate the first waste into a second waste smaller in size than the first waste, and the first waste at −20 ° C. The following is provided with a processing unit 62 that is cooled and crushed to obtain a crushed product, and a compounding unit 70 that is a mixture of the crushed product and the second waste to obtain a solid fuel. The processing unit 62 has a cooling unit 20 that cools the first waste using a coolant, and a crushing unit 30 that crushes the cooled first waste to obtain a pulverized product.

It differs from the manufacturing apparatus 100 of FIG. 1 in that it includes a sorting unit 10 and a compounding unit 70, and does not include a collecting unit 40, a flow path 25, and a flow path 32. In the sorting unit 10, the above-mentioned sorting step may be performed. The pulverized product and the second waste obtained in the pulverized portion 30 are introduced into the compounding unit 70. The compounding unit 70 may be a normal mixer. It is not necessary that the entire amount of the second waste is introduced into the compounding unit 70, and a part of the second waste may be used for another purpose. Since other configurations are the same as those of the manufacturing apparatus 100 of FIG. 1, the description of the manufacturing apparatus 100 can be applied. That is, the cooling unit 20 may perform a cooling step. The crushing unit 30 may perform a crushing step.

In the manufacturing apparatus 101, since the small-sized second waste is introduced into the compounding unit 70 without being introduced into the cooling unit 20 and the crushing unit 30, the production cost of solid fuel from the waste containing plastic is It is possible to easily produce a solid fuel having excellent combustibility while reducing the equipment burden. In the modified example, the second waste may be introduced into the pulverized portion 30 and blended without providing the blending portion 70. This also makes it possible to reduce the production cost of solid fuel.

The manufacturing apparatus 101 of FIG. 2 separates the first waste and the second waste according to the size of the waste, but the present invention is not limited to this. For example, in the case of waste containing carbon fiber reinforced plastic, the sorting section of the manufacturing equipment separates the first waste into the second waste having a higher carbon fiber reinforced plastic content than the first waste. It may be. In this case, the first waste is introduced into the cooling unit 20 (treatment unit 62), and the second waste, which is more difficult to crush than the first waste, is subjected to, for example, heat treatment to make the carbon fibers brittle. It may be crushed or used for other purposes such as carbon fiber recycling.

FIG. 3 is a diagram showing an example of a sorting unit used in the sorting step. The sorting unit 10A in FIG. 3 is at least one of an image acquisition unit 110 that acquires an image of the waste 150 and a second waste 152 having a higher carbon fiber content than the first waste 151 and the first waste 151. A detection unit 120 for detecting the above is provided.

The waste 150 containing the carbon fiber reinforced plastic is supplied on the conveyor 136 (left side in FIG. 3). The waste 150 supplied onto the conveyor 136 is conveyed by the conveyor 136 from left to right in FIG.

The image acquisition unit 110 includes a camera that captures a still image or a moving image of the waste 150. The image signal captured by the camera is input to the detection unit 120. The detection unit 120 detects information (pattern, shape, color, etc.) derived from carbon fibers in the image after performing image processing as necessary. Image information derived from carbon fibers includes a mesh pattern derived from fibers, a fluffy shape and a fluffy shape, and black or a color close to black. Of these image information, it is preferable to detect the pattern and shape from the viewpoint of improving the detection accuracy. Information derived from carbon fibers is quantified, and waste that is less than a predetermined threshold value may be detected as the first waste 151.

The image acquisition unit 110 includes a camera, and the camera captures a visible light image, an infrared image, an ultraviolet image, or an X-ray image of the inside of the waste by capturing the surface of each waste contained in the waste. It may be an image acquired by utilizing the nuclear magnetic resonance phenomenon. Of these, it is preferable to acquire a visible light image from the viewpoint of improving detection accuracy and workability. In addition, in order to image the surface structure and the internal structure of the waste, a plurality of types of images may be combined. Further, the image may be a moving image or a still image.

The position information of the waste is also input to the detection unit 120 from the image acquisition unit 110. The position information of the first waste 151 is input from the detection unit 120 to the control unit 131 that controls the robot arm 134. The control unit 131 controls the robot arm 134 based on the position information of the first waste 151 from the detection unit 120. The robot arm 134 grips the first waste 151 and lifts it from the conveyor 136. In this way, the robot arm 134 takes out the first waste 151 from the waste 150. The robot arm 134 moves to the right together with the control unit 131 along a guide unit (not shown) in FIG. 3, and releases the first waste 151 above the first storage unit 161. As a result, the first waste 151 is stored in the first storage unit 161.

On the other hand, the detection unit 120 quantifies the information derived from the carbon fibers, and the waste that is equal to or higher than the predetermined threshold value is conveyed as the second waste 152 by the conveyor 136, and is installed on the downstream side of the conveyor 136. It is housed in part 162. In this way, the waste 150 is separated into the first waste 151 and the second waste 152 having a higher content ratio of the carbon fiber reinforced plastic.

The first waste 151 may contain carbon fibers. Comparing the entire first waste 151 contained in the first storage unit 161 with the entire second waste 152 contained in the second storage unit 162, the entire first waste 151 is the second waste. If the carbon fiber content is lower than that of the entire product 152, the sorting unit 10A contributes to the smooth treatment of the waste containing the carbon fiber reinforced plastic. The second waste may be pulverized after embrittlement of carbon fibers by, for example, heat treatment, or may be used for other purposes such as recycling of carbon fibers.

The detection unit 120 may detect the first waste 151 and the second waste 152 based on any one of the patterns, shapes, and colors of the information derived from the carbon fibers. It may be performed based on a combination of two of these information, or may be performed based on a combination of these three pieces of information.

In the modified example, the waste may be classified into two types or three or more types according to the size of the pattern, shape or color derived from the carbon fiber, or the ratio thereof. For example, the first waste 151, which sets two thresholds, large and small, and has the smallest proportion of patterns, shapes, or colors derived from carbon fibers, and the second waste, which has the largest proportion of patterns, shapes, or colors derived from carbon fibers. The product 152 may be separated into a third waste in which the ratio of the pattern, shape or color derived from the carbon fiber is between the first waste 151 and the second waste 152. In this case, only the first waste 151 may be supplied to the cooling unit (processing unit), or only the first waste 151 and the second waste 152 may be supplied to the cooling unit (processing unit). At this time, the third waste having the highest carbon fiber content may be pulverized after being brittled by heat treatment, for example, or is supplied to a recycling facility for recycling the carbon fibers. May be good.

In yet another modification, the second waste 152 may be gripped by the robot arm 134 and taken out from the waste 150 arranged on the conveyor 136. In this case, the first waste 151, which is not taken out by the robot arm 134 and contains no or almost no carbon fiber, falls and is stored in the storage portion installed on the downstream side of the conveyor 136. In this way, the robot arm 134 may separate the waste 150 into the first waste 151 and the second waste 152 by taking out the second waste 152 from the waste 150.

In yet another modification, the waste may be separated into a first waste and a second waste using the size of the waste as an index. In this case, the detection unit 120 detects the size of the waste based on, for example, three-dimensional image information. Then, the first waste larger than a predetermined size can be grasped by the robot arm and taken out, and can be separated into the first waste and the second waste having a size smaller than this. The separation of the first waste and the second waste may be performed based on the image information or the mass.

In yet another modification, the waste may be separated into the first waste and the second waste by using the size of the carbon fiber contained in the waste as an index. In this case, the detection unit 120 detects the size of the carbon fibers contained in the waste, for example, based on three-dimensional image information. Then, the first waste containing carbon fibers of a predetermined size or more is grasped by the robot arm and taken out, and the first waste is separated into the second waste containing no carbon fibers of a predetermined size or more. be able to. The detection of the size of the carbon fiber may be performed based on, for example, a pattern, shape or color derived from the carbon fiber.

FIG. 4 is a diagram showing another example of the sorting unit used in the sorting step. The sorting unit 10B of FIG. 4 sorts the waste 150 containing the carbon fiber reinforced plastic according to the difference in electrostatic force due to its chargeability. The sorting unit 10B has a charging unit 111 that charges the waste 150 containing the carbon fiber reinforced plastic, and the waste 150 by changing the fall trajectory of the waste by electrostatic force, the first waste 151 and the second waste 152. Sort into.

The waste 150 containing the carbon fiber reinforced plastic is charged at the charging unit 111. The polarity of charging is not particularly limited. Examples of the charging unit 111 include those provided with an electric field generator. The waste 150 is charged by passing the waste 150 through the electric field generated by the electric field generator. The electrical resistivity of the carbon fiber reinforced plastic contained in the waste 150 is, for example, 1 × 10 ^-1 [Ω · m] or less. In contrast, the electrical resistivity of the waste made of an insulator such as a plastic that does not contain carbon fiber is ^{1 × 10 6 [Ω · m} ] or more. As described above, since the electrical resistivity of the waste differs greatly depending on the contained component, when the waste 150 passes through the electric field, the chargeability differs depending on the contained component.

A known electric field generator can be used for the charged portion 111. For example, a device provided with a needle-shaped electrode to which a high voltage is applied and a conductor and forms a corona discharge field between the two is provided. Can be mentioned. The charging unit 111 is not limited to the one provided with the electric field generator, and may be provided with a friction generator such as a rotating drum or a vibrator. In this case, static electricity can be generated and charged by the friction generated by moving the waste in a rotating drum or a vibrator. Even with such a method, the chargeability of waste differs depending on the components contained therein. From the viewpoint of sufficiently charging the waste, it is preferable that the inner wall of the friction generator is made of an insulator.

The charged waste 150 is supplied onto the conveyor 136 (left side of FIG. 4). The waste 150 supplied onto the conveyor 136 is conveyed by the conveyor 136 toward the charging drum 132 of the sorting unit 10B in FIG. The conveyor 136 is arranged below the charging drum 132. As a result, the waste 150 is supplied to the lower side of the rotating surface of the charging drum 132. By supplying the waste 150 to the lower side of the rotating surface in this way, the waste 150 can be separated even if the rotating surface and the waste 150 do not come into direct contact with each other.

The rotating surface of the charging drum 132 is charged to the opposite electrode to the waste. When the waste 150 reaches below the charging drum 132 by the conveyor 136, the first waste 151 is charged to the opposite electrode to the rotating surface of the charging drum 132, and the first waste 151 having a large potential difference from the rotating surface is subjected to an electrostatic attraction. Adheres to the rotating surface. After that, it rotates together with the rotating surface of the charging drum 132, is peeled off from the rotating surface by the scraper 133 provided along the rotating surface, falls, and is accommodated in the first accommodating portion 161. The scraper 133 may be, for example, a scraping brush or the like.

On the other hand, the second waste 152, which is not charged, or the second waste 152, which is charged at the opposite electrode to the rotating surface of the charged drum 132 but has a smaller potential difference from the rotating surface than the first waste 151, is Since the gravity is larger than the electrostatic attraction between the rotating surface of the charging drum 132 and the second waste 152, it falls without adhering to the rotating surface of the charging drum 132 and is housed in the second accommodating portion 162. As described above, the first waste 151 and the second waste 152 contained in the waste 150 are the first waste 151 and the second waste 151 according to their respective chargeability (potential difference with the rotating surface of the charging drum 132). The waste 152 is separated and stored in separate storage units. In this way, the waste 150 is separated into a first waste 151 and a second waste 152. A ground may be connected to the first accommodating portion 161 and the second accommodating portion 162 so that the first waste 151 and the second waste 152 contained therein are electrically neutral.

Since carbon fiber reinforced plastic is less likely to be charged than waste made of insulators such as paper scraps and resin, it tends to be collected as second waste 152. On the other hand, waste made of an insulator such as plastic is more likely to be charged than waste containing carbon fiber reinforced plastic, and therefore tends to be collected as first waste 151. That is, since the second waste 152 containing carbon fiber reinforced plastic has higher conductivity than the first waste 151 containing plastic, rubber, paper scraps, etc., the waste 150 containing such a waste component is used. When separated, the carbon fiber content of the second waste 152 is higher than that of the first waste 151.

However, the first waste 151 may contain carbon fibers. Comparing the entire first waste 151 contained in the first storage unit 161 with the entire second waste 152 contained in the second storage unit 162, the entire second waste 152 is the first waste. If the content ratio of the carbon fiber is higher than that of the whole product 151, the sorting unit 10B contributes to the smooth treatment of the waste containing the carbon fiber.

The sorting units 10A and 10B can reduce the amount of waste to be cooled by separating the waste 150. That is, it is possible to perform appropriate treatment according to the size of waste, the content ratio of carbon fiber reinforced plastic, or the size of carbon fiber. The waste that is not introduced into the cooling unit 20 may be, for example, heat-treated to embrittle the carbon fibers and then crushed, or the resin component contained in the waste may be treated with an acid-dissolving unit. Carbon fiber may be recycled.

The solid fuel obtained by the above-mentioned production method or the above-mentioned production apparatus may be used as a raw material fuel for cement, or may be used as a fuel for a kiln or a calcining furnace of a cement production facility. As a result, the fuel cost of the cement manufacturing facility can be reduced.

Although some embodiments have been described above, the present invention is not limited to the above embodiments. For example, the elements of the manufacturing apparatus 100 may be added to the manufacturing apparatus 101, or the elements of the manufacturing apparatus 101 may be added to the manufacturing apparatus 100.

The sorting unit 10A of FIG. 3 may include, for example, a gas discharger or a gas suction device configured so that the drop trajectory of the waste can be changed instead of the robot arm 134 and the control unit 131 thereof. By having a sorting unit provided with a gas discharger or a gas suction device, the waste can be sorted according to the size of the waste.

Further, for example, a sorting unit 10 may be provided between the cooling unit 20 and the crushing unit 30 of the manufacturing apparatus 100 to separate the first waste and the second waste. Then, only the first waste unit may be introduced into the crushing unit 30, and the second waste may be used for other purposes. Further, the sorting unit 10 is not limited to the above example, and may be, for example, one that sorts waste according to the difference in specific gravity.

According to the present disclosure, there is provided a method for producing a solid fuel capable of easily producing a solid fuel having excellent combustibility from waste containing plastic, and an apparatus for producing the solid fuel. Further, it is possible to provide a method of using a solid fuel which is easily produced from waste containing plastic and uses a solid fuel having excellent flammability.

10, 10A, 10B ... Sorting section, 20 ... Cooling section, 25 ... Flow path, 30 ... Crushing section, 32 ... Flow path, 40 ... Recovery section, 42 ... Classification section, 44 ... Conveyor section, 60, 62 ... Processing section , 70 ... Mixing unit, 100, 101 ... Manufacturing equipment, 110 ... Image acquisition unit, 111 ... Charging unit, 120 ... Detection unit, 131 ... Control unit, 132 ... Charging drum 133 ... Scraper, 134 ... Robot arm, 136 ... Conveyor, 150 ... waste, 151 ... first waste, 152 ... second waste, 161 ... first storage unit, 162 ... second storage unit.

Claims (17)

A method for producing a solid fuel, which comprises a treatment step of cooling a waste containing plastic to −20 ° C. or lower using a coolant and pulverizing the waste to obtain a pulverized product. The method for producing a solid fuel according to claim 1, wherein the waste is cooled to a temperature lower than −50 ° C. and higher than −100 ° C. and pulverized. The method for producing a solid fuel according to claim 1 or 2, wherein the coolant contains a liquefied or solidified inert gas. The method for producing a solid fuel according to claim 3, wherein the pulverization is performed in the atmosphere of the inert gas. The treatment step includes a cooling step of cooling the waste using the coolant and a crushing step of crushing the cooled waste to obtain the crushed product.
The method according to any one of claims 1 to 4, wherein the coolant used in the cooling step or a coolant different from the coolant used in the cooling step is introduced into the crushing step. How to make solid fuel. The method for producing a solid fuel according to any one of claims 1 to 5, wherein the waste contains carbon fiber reinforced plastic. Prior to the treatment step, based on at least one index selected from the group consisting of the size of the waste, the content of carbon fibers contained in the waste, and the size of the carbon fibers contained in the waste. , Has a sorting step to separate the waste into a plurality of pieces,
The method for producing a solid fuel according to any one of claims 1 to 6, wherein in the processing step, at least one waste separated in the sorting step is cooled and pulverized. The invention according to any one of claims 1 to 7, further comprising a recovery step of classifying the crushed product, recovering a part of the crushed product according to the size of the crushed product, and supplying the crushed product to the processing step. A method for producing solid fuel. The method for producing a solid fuel according to any one of claims 1 to 8, wherein the coolant contains at least one of liquid nitrogen and dry ice. A solid fuel manufacturing apparatus including a processing unit for cooling waste containing plastic to -20 ° C or lower using a coolant and pulverizing the waste to obtain the pulverized product. The solid fuel production apparatus according to claim 10, wherein the waste is cooled to a temperature lower than −50 ° C. and higher than −100 ° C. and pulverized. The processing unit includes a cooling unit that cools the waste using the coolant, and a crushing unit that crushes the cooled waste to obtain the crushed product.
The production of the solid fuel according to claim 10 or 11, wherein the pulverized portion has a flow path for introducing the coolant via the cooling portion or a coolant different from the coolant used in the cooling portion. apparatus. The solid fuel production apparatus according to any one of claims 10 to 12, wherein the waste contains carbon fiber reinforced plastic. Based on at least one index selected from the group consisting of the size of the waste, the content ratio of carbon fibers contained in the waste, and the size of carbon fibers contained in the waste on the upstream side of the treatment unit. It has a sorting unit that separates the waste into a plurality of parts.
The solid fuel production apparatus according to any one of claims 10 to 13, wherein in the processing unit, at least one waste separated by the separation unit is cooled and pulverized. The invention according to any one of claims 10 to 14, further comprising a recovery unit that classifies the pulverized product, recovers a part of the crushed product according to the size of the crushed product, and supplies the crushed product to the processing unit. Solid fuel manufacturing equipment. The solid fuel production apparatus according to any one of claims 10 to 15, wherein the coolant contains at least one of liquid nitrogen and dry ice. A method for using solid fuel, which comprises a step of burning the solid fuel obtained by the production method according to any one of claims 1 to 9 in a kiln or a calcining furnace of a cement production facility.

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