Abstract:
A method for recycling comprises a pulverization step (S 1 ) of pulverizing thermoplastic resin molded articles, each having a different softening point in a resin substrate and having a metal part and a coupling film, a metal-material selection-removal step (S 3 ) of selecting and removing a metal material from pulverized pieces, a pulverized resin-material selection step (S 5 ) of selecting a target pulverized resin material for recycling by allowing the pulverized pieces from which the pulverized metal material has been removed to drop and by ejecting gas towards either one of the target pulverized resin material and a non-target pulverized resin material for changing a drop direction thereof, and a coating-film peeling step (S 7 ) of peeling the coating film from the resin substrate by applying a shearing force to the target pulverized resin material under the softening point of the resin substrate of the target pulverized resin material for recycling.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    The present invention relates to a method for recycling a waste material of a thermoplastic resin molded article as resources. 
         [0002]    Conventionally, some bumpers for an automotive vehicle as a waste material have been collected and pulverized, and resin materials for recycling have been obtained from the pulverized bumpers. 
         [0003]    Herein, it is generally necessary that metal materials are removed from the pulverized bumper pieces obtained, then target resin materials for recycling are selected from the bumper pieces without the metal materials, and coating films coated on the selected resin materials are peeled from their resin substrates. 
         [0004]    Japanese Patent Laid-Open Publication No. 2002-254430 discloses a crasher operative to crash (pulverize) resin molded articles, such as PET bottles, and a centrifugal separator operative to separate specified resin-material pieces from the crashed (pulverized) pieces according to difference in specific gravity thereof. 
         [0005]    Japanese Patent Laid-Open Publication No. 2006-15721 discloses a metal selection device operative to select metal-based pieces from crashed pieces of thermoplastic resin molded articles by using magnets, and a mixing tank operative to select target resin-material pieces from the crashed pieces without metal-based pieces according to the specific gravity difference. 
         [0006]    Herein, in a case where resin-material pieces still having coating films coated thereon are used as recycling materials, there is a concern that recycled products obtained may provide poor physical properties or poor appearances. The above-described publications disclose no specific treatments of peeling the coating films from substrates of the crashed resin-material pieces. 
       SUMMARY OF THE INVENTION 
       [0007]    The present invention has been devised in view of the above-described matter, and an object of the present invention is to provide a method for recycling a waste material of a thermoplastic resin molded article as resources that can obtain a coating-film-free resin-material as a material for recycling easily and efficiently. 
         [0008]    According to the present invention, there is provided a method for recycling a waste material of a thermoplastic resin molded article as resources, comprising a pulverization step of pulverizing a mixture of plural kinds of thermoplastic resin molded articles, each having a different softening point in a resin substrate thereof and having a metal part attached thereto and a coating film coated thereon, a metal-material selection-removal step of selecting and removing a metal material of the pulverized metal part from pulverized pieces obtained through the pulverization step by a selection apparatus, a pulverized resin-material selection step of selecting a target pulverized resin material for recycling by allowing the pulverized pieces from which the pulverized metal material has been removed through the metal-material selection-removal step to drop and by ejecting gas toward either one of the target pulverized resin material for recycling and a non-target pulverized resin material, which are contained in the pulverized pieces dropping, for changing a drop direction thereof, and a coating-film peeling step of peeling the coating film from the resin substrate by applying a shearing force to the target pulverized resin material for recycling that has been selected through the pulverized resin-material selection step under the softening point of the resin substrate of the target pulverized resin material for recycling. 
         [0009]    According to the present invention, the metal parts attached to the thermoplastic resin molded articles are pulverized and the metal material of the pulverized metal part is selected and removed from the pulverized pieces by the selection apparatus. Thereby, removal of the metal material can be properly automated and facilitated. 
         [0010]    Further, the target pulverized resin material for recycling is selected from the pulverized pieces from which the pulverized metal material has been removed by the gas ejection. Herein, it may be difficult that the gas is ejected toward a specified pulverized resin material in a case where the pulverized pieces are in a lump state. Further, according to the present invention, however, since the pulverized pieces are configured to be allowed to drop, they can be made move smoothly in a certain direction, passing a gas-ejection point without staying, thereby enabling the gas ejection toward the specified pulverized resin material. Thus, any particular devises to provide the smooth moving of the pulverized pieces, such as a conveyer, may not be necessary additionally. 
         [0011]    Also, in a case where the metal material is contained in the pulverized pieces dropping, it may be necessary to eject the gas toward the metal material and the non-target pulverized resin material or eject toward the target pulverized resin material in order to select the target pulverized resin material. In this case, since the dropping speeds of the metal material and the pulverized resin material are different to each other, adjusting of timing of the gas ejection may be difficult. According to the present invention, however, since the metal material has been removed through the metal-material selection-removal step, the dropping pulverized pieces consist of the resin material basically and thus the dropping speeds of the pieces becomes substantially the same. Thereby, the adjusting of timing of the gas ejection can be made easier, so that the selection of the target pulverized resin material can be accomplished easily and accurately. 
         [0012]    Further, the shearing force is applied to the target pulverized resin material for recycling under the softening point of the resin substrate of the target pulverized resin material. Thereby, since the sheering force is applied when the substrate has been softened enough, the coating film can be surely peeled from the resin substrate. Accordingly, the coating-film-free resin-material as the material for recycling can be obtained easily and efficiently. 
         [0013]    Also, if the above-described sheering force was also applied to the non-target pulverized resin material in the coating-film peeling step and the softening pint of the resin substrate of the non-target pulverized resin material was lower than that of the substrate resin of the target pulverized resin material for recycling, the resin substrate of the non-target pulverized resin material would be melted under the temperature of the softening point of the substrate resin of the target pulverized resin material for recycling. This melted resin material would be attached to the surface of the target pulverized resin material for recycling, so that there is a concern that the coating film coated on the resin substrate of the target pulverized resin material might not be peeled properly from the resin substrate. According to the present invention, however, since the non-target pulverized resin material has been already removed in the pulverized resin-material selection step, the above-described concern can be prevented in the coating-film peeling step. Thereby, the coating film coated on the resin substrate can be peeled surely from the resin substrate, so that the coating-film-free resin-material can be obtained further easily and efficiently. 
         [0014]    According to an embodiment of the present invention, the coating film is made from a thermosetting material. Thereby, the coating film coated on the resin substrate of the target pulverized resin material for recycling is made in a state where it can be peeled easily from the resin substrate under the softening point in the coating-film peeling step. Accordingly, the coating film coated on the resin substrate of the target pulverized resin material for recycling can be peeled surely. The effects of the present invention can be surely achieved. 
         [0015]    According to another embodiment of the present invention, the coating film on the resin substrate is configured to be not softened under the softening point of the resin substrate in the coating-film peeling step. Thereby, the coating film coated on the resin substrate can be peeled further surely. The effects of the present invention can be surely achieved. 
         [0016]    According to another embodiment of the present invention, the method further comprising a large-sized waste-material removal step of removing a material that is larger than the metal part from an untreated waste material for recycling, wherein the rest of the waste material for recycling from which the large-sized waste-material has been removed through the large-sized waste-material removal step is supplied to the pulverization step to be pulverized. Thereby, since the larger material than the metal part has been removed from the untreated waste material for recycling in the large-sized waste-material removal step prior to the pulverization step, burdens of apparatuses that work in the respective steps after the pulverization step can be properly lightened. 
         [0017]    According to another embodiment of the present invention, the method further comprising a coating-film-free resin-material selection step of selecting the pulverized resin material without the coating film that has been removed through the coating-film peeling step from the pulverized resin material with the coating film. Thereby, since the pulverized resin material without the coating film is selected from the pulverized resin material with the coating film in the coating-film-free resin-material selection step, a collection ratio of the pulverized resin material without the coating film can be further improved. 
         [0018]    According to another embodiment of the present invention, the target pulverized resin material for recycling is comprised of plural kinds of pulverized resin materials that have similar softening points of resin substrate to each other. Herein, in a case where the shearing force is applied to the plural kinds of pulverized resin materials under a stepwise-increased temperature within a temperature range that is lower than the highest softening point in the coating-film peeling step, for example, the shearing force may be applied to the pulverized resin materials in a state where the coating film can be easily peeled. Thereby, each of coating films coated on the resin substrates can be properly removed. 
         [0019]    According to another embodiment of the present invention, the method further comprising a pulverized resin-material melt step of melting the pulverized resin material without the coating film that has been removed through the coating-film peeling step for obtaining a material for remolding. Thereby, since the material for remolding is obtained by melting the pulverized resin material without the coating film, the superior material for remolding in the physical properties or appearances can be obtained. 
         [0020]    According to another embodiment of the present invention, the waste material to be treated by the method is a bumper for an automotive vehicle. Herein, the bumper for an automotive vehicle is generally comprised of the plural kinds of thermoplastic resin molded articles, each having the different softening point in the resin substrate thereof and having the metal part attached thereto and the coating film coated thereon. Accordingly, the effects of the present invention can be properly achieved. 
         [0021]    Other features, aspects, and advantages of the present invention will become apparent from the following description which refers to the accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0022]      FIG. 1  is a diagram partially showing a system for recycling a waste material of a thermoplastic resin molded article as resources according to the present invention. 
           [0023]      FIG. 2  is another diagram partially showing the system for recycling a waste material of a thermoplastic resin molded article as resources according to the present invention. 
           [0024]      FIG. 3  is a diagram showing an ejection nozzle of an ejector. 
           [0025]      FIG. 4  is a diagram showing a state in which a coating film of a pulverized resin material is removed from a substrate. 
           [0026]      FIG. 5  is a diagram showing a control block of the system for recycling of the present embodiment. 
           [0027]      FIG. 6  is a flowchart showing a treatment process that is executed by a CPU in the present embodiment. 
           [0028]      FIG. 7  is a flowchart showing details of a metal-material selection-removal treatment. 
           [0029]      FIG. 8  is a flowchart showing details of a pulverized material selection treatment. 
           [0030]      FIG. 9  is a flowchart showing details of a coating-film peeling treatment. 
           [0031]      FIG. 10  is a flowchart showing details of a coating-film-free resin-material selection treatment. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0032]    Hereinafter, a preferred embodiment of the present invention will be described referring to the accompanying drawings. 
         [0033]      FIGS. 1 and 2  are diagrams that partially show a system for recycling a waste material of a thermoplastic resin molded article as resources according to the present invention, respectively. 
         [0034]    In the present embodiment, a material to be treated by the system for recycling is used bumper A for an automotive vehicle. The bumper A is comprised of plural kinds of thermoplastic resin molded articles, each having a different softening point in a resin substrate thereof and having a metal part attached thereto, such as a screw, and a coating film coated thereon that is made from a thermosetting material. 
         [0035]    The system for recycling comprises, as shown in  FIGS. 1 and 2 , a pulverization apparatus  10 , a metal-material selection apparatus  30 , a pulverized material selection apparatus  50 , a coating-film peeling apparatus  70 , a coating-film-free material selection apparatus  90 , and conveyer apparatuses  120 ,  121 ,  122 ,  123 . 
         [0036]    [Pulverization Apparatus  10 ] 
         [0037]    The pulverization apparatus  10 , which pulverizes the bumper A, comprises a pulverization container  11  and a cutter mill  12  that is provided so as to rotate in the container  11 . A plurality of rotating edges  13  are formed integrally at a periphery of the cutter mill  12 . 
         [0038]    An inlet  14  is provided at the top of the pulverization apparatus  10  from which the bumper A is supplied, and an outlet  15  is provided at the bottom from which pulverized pieces of the bumper A are discharged. The bumper A supplied from the inlet  14  is pulverized by the rotating cutter mill  12 , and the pulverized pieces of the bumper A are discharged to the outside from the outlet  15 . 
         [0039]    The pulverized pieces of the bumper A from the pulverization apparatus  10  contain metal materials B of pulverized metal parts, such as screws, pulverized resin materials for recycling C that can be recycled as a material of a bumper remolded article, and other pulverized resin materials D. Coating materials of the above-described coating film are coated (attached) on the pulverized resin materials C, D. Herein, any material that is larger than the above-described metal parts has been removed in advance from the untreated material to be supplied to the above-described pulverization apparatus  10 . Thereby, since the respective apparatuses of the system shown in  FIGS. 1 and 2 , including the pulverization apparatus  10 , need not to treat large-sized materials, burdens of these apparatuses can be properly lightened. 
         [0040]    [Conveyer Apparatus  120 ] 
         [0041]    The conveyer apparatus  120  coveys the pulverized pieces of the bumper A from the pulverization apparatus  10  to the metal-material selection apparatus  30 . The pulverized pieces discharged from the outlet  15  of the pulverization apparatus  10  are conveyed by the conveyer apparatus  120  to a hopper  34 , which will be described, of the metal-material selection apparatus  30 . 
         [0042]    [Metal-Material Selection Apparatus  30 ] 
         [0043]    The metal-material selection apparatus  30  selects and removes the metal materials B from the pulverized pieces of the bumper A. The metal-material selection apparatus  30  comprises a selection container  31 , a mesh-shaped belt  32 , an air-supply fan (blower)  33 , and collection tanks  37 ,  38 . 
         [0044]    The belt  32  is provided in the selection container  31  so as to extend between both-side faces of the container. Its extension is provided so as to be inclined as shown, and the belt  32  is configured so that it moves so as to vibrate in a direction of the inclination. An upper face  32   a  of the belt  32  is formed in a saw shape. Herein, the saw shape is formed in such a manner that an inclination angle of the saw differs between a left (upper) side and a right (lower) side as shown. 
         [0045]    The air-supply fan  33  is disposed below the belt  32  so as to provide the air upward, in a direction of an arrow E in  FIG. 1 . 
         [0046]    At the top of the section container  31  is provided the hopper  34 . The hopper  34  is located above the belt  32 . At both sides of the section container  31  are provided outlets  35 ,  36  that are respectively located on an extension line of the belt  32 . The collection tanks  37 ,  38  are disposed below the outlets  35 ,  36  outside the selection container  31 . 
         [0047]    In the metal-material selection apparatus  30 , the pulverized pieces supplied from the hopper  34  drop on and along the belt  32 . Herein, the belt  32  vibrates and the fan  33  supplies the air toward the belt  32 . The air from the fan  33  passes through meshes of the belt  32  and is blown against the dropped pulverized pieces on the belt  32 . The vibration in the slant direction of the belt  32  is applied to the dropped pulverized pieces. As a result, the metal materials B having a relatively high density is brought up to the upper end of the belt  32 , while the resin materials C, D having a relatively low density is brought down to the lower end of the belt  32 . The metal materials B drop into the collection tank  37  from the outlet  35 , and the resin materials C, D drop into the collection tank  38  from the outlet  36 . Thus, the mixture of the pulverized resin materials C, D that are obtained by removing the metal materials B from the pulverized pieces is obtained. 
         [0048]    [Conveyer Apparatus  121 ] 
         [0049]    The conveyer apparatus  121  coveys the pulverized resin materials C, D that have been obtained through the metal-material selection apparatus  30  to the pulverized material selection apparatus  50 . The pulverized pieces collected into the tank  38  of the metal-material selection apparatus  30  are conveyed by the conveyer apparatus  121  to a hopper  51 , which will be described, of the pulverized material selection apparatus  50 . 
         [0050]    [Pulverized Material Selection Apparatus  50 ] 
         [0051]    The pulverized material selection apparatus  50  shown in  FIG. 2  selects the pulverized resin materials C from the mixture of the pulverized resin materials C, D. This apparatus  50  comprises the hopper  51  for the pulverized resin materials C, D, a shoot portion  52  to guide the pulverized resin materials C, D dropping in a specified direction, a shoot divergence portion  53  that diverges from a middle portion of the shoot portion  52 , and collection tanks  54 ,  55  to collect the pulverized resin materials C and the pulverized resin materials D separately. 
         [0052]    The shoot portion  52  is provided obliquely with a specified inclination angle so as to extend toward the collection tank  54  from the lower of the hopper  51 . A portion of the shoot portion  52 , which is just above the divergence point of the shoot divergence portion  53 , is made of a colorless and transparent material, which constitutes a detection portion  56 . Herein, part of the shoot portion  52  that corresponds to the detection portion  56  may be removed, instead of using the colorless and transparent material. That is, an optical image of the pulverized resin materials C, D can be taken through the shoot portion  52 . 
         [0053]    Further, at the pulverized material selection apparatus  50  are provided infrared-ray emitters  57 ,  58  operative to emit infrared rays to the pulverized resin materials C, D dropping passing through the detection portion  56  and infrared-ray sensors  59 ,  60  operative to take infrared photographs of the pulverized resin materials C, D emitting reflection of the infrared rays. 
         [0054]    The infrared-ray emitter  57  is disposed on an upper side of the shoot portion  52  at the detection portion  56 , and the infrared-ray sensor  59  is disposed on the upper side of the shoot portion  52  so as to receive the reflection at the pulverized resin materials C, D of the infrared rays emitted from the infrared-ray emitter  57 . 
         [0055]    The infrared-ray emitter  58  is disposed on a lower side of the shoot portion  52  at the detection portion  56 , and the infrared-ray sensor  60  is disposed on the lower side of the shoot portion  52  so as to receive the reflection at the pulverized resin materials C, D of the infrared rays emitted from the infrared-ray emitter  58 . 
         [0056]    Thus, since the infrared-ray sensors  59 , 60  receive the reflection of the infrared-rays at the pulverized resin materials C, D form plural directions, the reflection can be received accurately regardless of positions of the pulverized resin materials C, D. 
         [0057]    Further, at the divergence point of the shoot divergence portion  53  from the shoot portion  52  is provided an ejector  61  to eject air toward the detection portion  56 . As shown in  FIG. 3 , the ejector  61  has a plurality of ejection nozzles  62  along an entire width of a dropping area of the pulverized resin materials C, D. 
         [0058]    In the pulverized material selection apparatus  50 , the air is blown against the pulverized resin materials D dropping the detection portion  56  based on the taken photos by the infrared-ray sensors  59 , 60  and thereby the pulverized resin materials D are changed in the direction from the shoot portion  52  to the shoot divergence portion  53 . As a result, the pulverized resin materials C drop into the collection tank  54 , and the pulverized resin materials D drop into the collection tank  55 . Thus, the pulverized resin materials C are selected from the mixture of the pulverized resin materials C, D. 
         [0059]    [Conveyer Apparatus  122 ] 
         [0060]    The conveyer apparatus  122  coveys the pulverized resin materials C that have been selected by the pulverized material selection apparatus  50  to the coating-film peeling apparatus  70 . The pulverized resin materials C collected into the tank  54  of the pulverized material selection apparatus  50  are conveyed by the conveyer apparatus  122  to a hopper  74 , which will be described, of the coating-film peeling apparatus  70 . 
         [0061]    [Coating-Film Peeling Apparatus  70 ] 
         [0062]    The coating-film peeling apparatus  70 , which operates to peel coating films coated on the pulverized resin materials C from the substrates, comprises a cylinder  71 , a screw  72  that is provided so as to rotate in the cylinder  71 , and a heater  73  to maintain an inner temperature of the cylinder  71  to a specified temperature. Herein, the coating-film peeling apparatus  70  may be comprised of a kneader mixer. 
         [0063]    A hopper  74  for supply of the pulverized resin materials C is provided at an end portion of the cylinder  71 , and at the other end portion of the cylinder  71  is provided an outlet  75 . 
         [0064]    Also, screw edges  76  are provided at the peripheral face of the screw  72  so as to extend in an axial direction of the screw with a constant pitch. 
         [0065]    The pulverized resin materials C supplied in the cylinder  71  from the hopper are supplied into a space between projections  76   a  of the screw edges  76  in the coating-film peeling apparatus  70 . 
         [0066]    Herein, the inner temperature of the cylinder  71  is adjusted and Maintained by the heater  73  to the specified temperature that is a softening point of the substrate of the pulverized resin materials C. Under this softening temperature the coating film on the substrate of the pulverized resin materials C is not softened yet. Thus, the substrate of the pulverized resin materials C is softened, while the coating film is not softened. Accordingly, there is provided a situation where the coating film can be peeled easily from the substrate in the coating-film peeling apparatus  70 . Herein, the rotation of the screw  72  causes a shearing force applying to the pulverized resin materials C, so that the coating film can be peeled from the substrate of the pulverized resin materials C as shown in  FIG. 4 . 
         [0067]    The pulverized resin materials C is further conveyed to a direction of an arrow F according to the rotation of the screw  72  and finally discharged from the outlet  75  to the outside of the coating-film peeling apparatus  70 . Herein, the pulverized resin materials C discharged from the outlet  75  contains some pulverized resin materials C, coating film of which has not been peeled off and still remains. Hereinafter, the pulverized resin materials C without their coating film (has been peeled off) are referred to as “OK article C 1 ”, and the pulverized resin materials C with their coating film (still remain) are referred to as “NG article C 2 .” 
         [0068]    [Conveyer Apparatus  123 ] 
         [0069]    The conveyer apparatus  123  coveys the above-described OK articles C 1  and NG articles C 2  from the coating-film peeling apparatus  70  to the coating film-free material selection apparatus  90 . The mixture articles C 1 , C 2  discharged from the outlet  75  are conveyed by the conveyer apparatus  123  to a hopper  91 , which will be described, of the coating-film-free material selection apparatus  90 . 
         [0070]    [Coating-Film-Free Material Apparatus  90 ] 
         [0071]    The coating-film-free material selection apparatus  90 , which select the OK articles C 1  from the mixture of the articles C 1 , C 2 , comprises a hopper  91 , a shoot portion  92 , a shoot divergence portion  93 , collection tanks  94 ,  95 , and an ejector  99 , which are similar to those of the pulverized material selection apparatus  50 . Additionally, the apparatus  90  comprises CCD sensors  100 ,  101 , background members  102 ,  103 , plural color fluorescent lights  104 , and color-difference sensor  300 , which is shown in  FIG. 5 . A portion of the shoot portion  92 , which is just above the divergence point of the shoot divergence portion  93 , is made of a colorless and transparent material, which constitutes a detection portion  105 , like the pulverized material selection apparatus  50 . 
         [0072]    The CCD sensor  100  is disposed on an upper side of the shoot portion  92  at the detection portion  105 , and the background member  102  is disposed on the lower side of the shoot portion  92 , facing the CCD sensor  100 . 
         [0073]    The CCD sensor  101  is disposed on the lower side of the shoot portion  92  at the detection portion  105  in such a manner that its light axis crosses the CCD sensor  100  and the background member  102  with a specified angle. The background member  103  is disposed on the upper side of the shoot portion  92 , facing the CCD sensor  101 . 
         [0074]    The background members  102 ,  103  have a different color from the color of the coating film of the articles C 1 , C 2 , such as black, that is put thereon. The CCD sensors  100 ,  101  can detect the coating film of the NG articles C 2  based on color differences in brightness, chroma, or hue between the coating film and the background members  102 ,  103 . 
         [0075]    The color-difference sensor  300  detects difference in color between the background members  102 ,  103  and surfaces of the articles C 1 , C 2  according to the photos taken by the CCD sensors  100 ,  101 . Thus, detection of existence of the coating film by the CCD sensors  100 ,  101  is executed from plural directions, so that the NG articles C 2  can be detected accurately regardless of the position of the articles. 
         [0076]    Also, since the CCD sensors  100 ,  101  detect the coating film of the NG articles C 2  based on the color differences in brightness, chroma, or hue between the coating film and the background members  102 ,  103 , any error detection can be prevented properly, thereby improving the coating-film detection accuracy easily and effectively. 
         [0077]    The color fluorescent lights  104  are provided near the lenses of the CCD sensors  100 ,  101 . It may be preferable that the color of the color fluorescent lights  104  is green in order to reduce the error detection. The color fluorescent lights  104  may be comprised of a halogen lamp. 
         [0078]    In the coating-film-free material selection apparatus  90 , the air is blown against the NG articles C 2  dropping the detection portion  105  based on the taken photos by the CCD sensors  100 , 101  and thereby the NG articles C 2  are changed in its dropping direction from the shoot portion  92  to the shoot divergence portion  93 . As a result, the OK articles C 1  drop into the collection tank  94 , and the NC articles C 2  drop into the collection tank  95 . Thus, the OK articles C 1  and the NG articles C 2  are selected from each other. 
         [0079]      FIG. 5  is a diagram showing a control block of the system for recycling of the present embodiment. 
         [0080]    A controller  200  in  FIG. 5  comprises a ROM  201  that stores a control program for the system for recycling, a CPU  202  that executes processing, which will be described below, according to the program, and a RAM  203  that holds processing results and the like. 
         [0081]    The CPU  202  drives the cutter mill  12  of the pulverization apparatus  10  according to the program. 
         [0082]    The CPU  202  makes the belt  32  vibrate and drives the fan  33  of the metal-material selection apparatus  30  according to the program. 
         [0083]    The CPU  202  drives the program the infrared-ray emitters  57 ,  58  and controls the ejector  61  based on the sensing signals of the infrared-ray sensors  59 ,  60  of the pulverized material selection apparatus  50  according to the program. 
         [0084]    Also, the CPU  202  drives the screw  72  and operates the heater  73  to keep the inner temperature at the specified setting temperature of the coating-film peeling apparatus  70  according to the program. 
         [0085]    Further, the CPU  202  controls the ejector  99  and color fluorescent lights  104  based on the sensing signals of the CCD sensors  100 ,  101  and color-difference sensor  300  of the coating-film-free material selection apparatus  90  according to the program. 
         [0086]    Also, the CPU  202  drives the conveyer apparatuses  120 ,  121 ,  122 ,  123  according to the program. 
         [0087]      FIG. 6  is a flowchart showing the treatment process that is executed by the CPU  202  in the present embodiment. 
         [0088]    When the bumper A is supplied into the pulverization container  11  from the inlet  14 , the CPU  202  drives the cutter mill  12  and pulverizes the bumper A (step S 1 ). 
         [0089]    Next, the CPU  202  drives the conveyer apparatus  120  and thereby the pulverized bumper pieces discharged from the pulverization apparatus  10  are conveyed to the metal-material selection apparatus  30  (step S 2 ). 
         [0090]    Then, the CPU  202  makes the metal-material selection apparatus  30  execute the metal-material selection treatment (step S 3 ). This metal-material selection treatment will be described referring to  FIG. 7 . 
         [0091]    At first, the CPU  202  makes the belt  32  vibrate (step S 30 ) and then makes the air-supply fan  33  operate (step S 31 ). 
         [0092]    Returning to  FIG. 6 , the CPU  202  drives the conveyer apparatus  121  and thereby the mixture of the pulverized resin materials C, D discharged from the metal-material selection apparatus  30  are conveyed to the pulverized material selection apparatus  50  (step S 4 ). Thus, the pulverized resin materials C, D are supplied into the pulverized material selection apparatus  50 . 
         [0093]    Then, the CPU  202  makes the pulverized material selection apparatus  50  execute the pulverized material selection treatment (step S 5 ). This pulverized material selection treatment will be described referring to  FIG. 8 . 
         [0094]    At first, the CPU  202  makes the infrared-ray emitters  57 ,  58  and the infrared-ray sensors  59 ,  60  of the pulverized material selection apparatus  50  operate (step S 50 ), and thereby photos of the pulverized resin materials C, D dropping at the shoot portion  52  are taken at the detection portion  56 . 
         [0095]    Then, the CPU  202  detects spectral characteristics of the reflected lights from the pulverized resin materials C, D based on the taken photos and then detects a wavelength of an absorption peak of the reflected lights based on the detected spectral characteristics (step S 51 ). 
         [0096]    Next, the CPU  202  determines whether the wavelength of absorption peak of the reflected light is within a specified range or not (step S 52 ). When it is determined that it is not within the specified range (NO in the step S 52 ), the pulverized resin material dropping at the detection portion  56  is considered as the pulverized resin materials C, then the control sequence returns to the step S 51 , without operating the ejector  61 . Herein, the pulverized resin materials C dropping at the detection portion  56  are collected into the collection tank  54 . 
         [0097]    Meanwhile, when it is determined that the wavelength of absorption peak of the reflected light is within the specified range (YES in the step S 52 ), the pulverized resin material dropping at the detection portion  56  is considered as the pulverized resin materials D, then the ejection nozzle  62  of the ejector  61  are decided (step S 53 ). That is, the specified ejection nozzle  62  that corresponds to the dropping position of the pulverized resin materials D is selected from the plural ejection nozzles  62  shown in  FIG. 3 . 
         [0098]    Next, the CPU  202  operates the ejector  61  to blow the air from the ejection nozzle  62  against the pulverized resin materials D at their dropping timing so that the dropping direction of the pulverized resin materials D is changed toward the shoot divergence portion  53  (step S 54 ). Thereby, the pulverized resin materials D are collected into the collection tank  55 . 
         [0099]    Subsequently, the CPU  202  determines whether all of the pulverized resin materials C, D supplied in the step S 4  have dropped or not (step S 55 ). When all of them have not dropped yet (NO in the step S 55 ), the processing from the step S 51  continues until all of them have dropped. 
         [0100]    Meanwhile, when all of pulverized resin materials C, D have dropped (YES in the step S 55 ), the CPU  202  stops operations of the infrared-ray emitters  57 ,  58  and the infrared-ray sensors  59 ,  60  (step S 56 ). After the step S 56  has been executed, the pulverized resin-material selection treatment shown in  FIG. 8  is complete. 
         [0101]    Returning to  FIG. 6 , the CPU.  202  drives the conveyer  122  and thereby the pulverized resin materials C collected into the collection tank  54  are conveyed to the coating-film peeling apparatus  70  (step S 6 ). Thereby, the pulverized resin materials C are supplied to the coating-film peeling apparatus  70 . 
         [0102]    Next, the CPU  202  makes the coating-film peeling apparatus  70  execute the coating-film peeling treatment (step S 7 ). The coating-film peeling treatment will be described referring to  FIG. 9 . 
         [0103]    First, the CPU  202  operates the heater  73  to set the inner temperature of the cylinder to the softening point of the substrate of the pulverized resin materials C (step S 70 ). 
         [0104]    Then, the CPU  202  drives the screw  72  for a specified term and thereby the coating film is peeled from the substrate of the pulverized resin materials C (step S 71 ). 
         [0105]    Returning to  FIG. 6 , the CPU  202  drives the conveyer  123  and thereby the pulverized resin materials C discharged from the coating-film peeling apparatus  70  are conveyed to the coating-film-free material selection apparatus  90  (step S 8 ). Thereby, the pulverized resin materials C are supplied to the coating-film-free material selection apparatus  90 . 
         [0106]    Next, the CPU  202  makes the coating-film-free material selection apparatus  90  execute the coating-film-free material selection treatment (step S 9 ). The coating-film-free material selection treatment will be described referring to  FIG. 10 . 
         [0107]    First, the CPU  202  operates the CCD sensors  100 ,  101  and the color fluorescent lights  104  (step S 90 ), and thereby the photos of the pulverized resin materials C dropping on the shoot portion  92  are taken at the detection portion  105 . 
         [0108]    Next, the CPU  202  makes the color-difference sensor  300  detect difference in color (step S 91 ). 
         [0109]    Then, the CPU  202  compares the detected color difference with a standard value and it is determined whether the detected color difference is greater than the standard value or not (step S 92 ). When the detected color difference is lower than the standard value (NO in the step S 92 ), the pulverized resin materials C dropping at the detection portion  105  is considered as the OK articles C 1  and the control sequence returns to the step S 91 , without operating the ejector  99 . The OK articles C 1  are collected into the collection tank  94  from the shoot portion  92 . 
         [0110]    Meanwhile, when the detected color difference is the standard value or more (YES in the step S 92 ), the pulverized resin materials C dropping at the detection portion  105  is considered as the NG articles C 2  and the specified ejection nozzle corresponding to the dropping position of the NG articles C 2  is selected as the nozzle to eject the air (step S 93 ). 
         [0111]    Then, the CPU  202  makes the ejector  99  eject the air from the selected ejection nozzle at the dropping timing of the NG articles C 2 , and thereby the dropping direction of the NG articles C 2  is charged to the shoot divergence portion  93  (step S 94 ). Thereby, the NG articles C 2  are collected into the collection tank  95 . 
         [0112]    Subsequently, the CPU  202  determines whether all of the pulverized resin materials C supplied in the step S 8  have dropped or not (step S 95 ). When all of them have not dropped yet (NO in the step S 95 ), the processing from the step S 91  continues until all of them have dropped. 
         [0113]    Meanwhile, when all of pulverized resin materials C have dropped (YES in the step S 95 ), the CPU  202  stops operations of the CCD sensors  100 ,  101  and the color fluorescent lights  104  (step S 96 ). 
         [0114]    According to the present embodiment, the metal parts attached to the thermoplastic resin molded articles of the bumper A are pulverized and the metal material of the pulverized metal part is selected and removed from the pulverized pieces by the metal-material selection apparatus  30 . Thereby, removal of the metal material can be properly automated and facilitated. 
         [0115]    Further, in the pulverized material selection apparatus  50  the pulverized pieces C, D are configured to be allowed to drop and pass through the divergence point of the shoot portion  52  and the shoot divergence portion  53  where the air is ejected. Thus, any particular devises to make the pulverized pieces C, D pass through the air-ejection point, such as the conveyer, may not be necessary additionally. 
         [0116]    Also, since the metal material B has been removed in the metal-material selection apparatus  30 , the dropping pulverized pieces consist of the resin material basically in the pulverized material selection apparatus  50  and thus the dropping speed of the pieces becomes substantially the same. Thereby, the adjusting of timing of the air ejection can be easy, so that the selection of the pulverized resin materials C can be accomplished easily and accurately. 
         [0117]    Further, the shearing force is applied to the pulverized resin materials C under the softening point of the resin substrate of the pulverized resin materials C. Thereby, since the sheering force is applied when the substrate has been softened, the coating film can be surely peeled from the resin substrate of the pulverized resin materials C. Accordingly, the coating-film-free resin-material as the material for recycling can be obtained easily and efficiently. 
         [0118]    Herein, if the pulverized resin materials D were also supplied into the coating-film peeling apparatus  70  and the softening pint of the resin substrate of the pulverized resin materials D was lower than that of the substrate resin of the pulverized resin materials C, the resin substrate of the pulverized resin materials D would be melted under the temperature of the softening point of the substrate resin of the pulverized resin materials C. This melted resin material would be attached to the surface of the pulverized resin materials C, so that there is a concern that the coating film coated on the resin substrate of the pulverized resin materials C might not be peeled properly from the resin substrate. According to the present invention, however, since the pulverized resin materials D has been already removed in the pulverized material selection apparatus  50  and only the pulverized resin materials C are supplied to the coating-film peeling apparatus  70 , the above-described concern can be prevented. Thereby, the coating film coated on the resin substrate of the pulverized resin materials C can be peeled surely from the resin substrate, so that the coating-film-free resin-material can be obtained further easily and efficiently. 
         [0119]    Also, since the coating film of the pulverized resin materials C is made from the thermosetting material, the coating film coated on the resin substrate of the pulverized resin materials C is made in a state where it can be peeled easily from the resin substrate under the softening point in the coating-film peeling treatment. Accordingly, the coating film coated on the resin substrate of the pulverized resin materials C can be peeled surely. 
         [0120]    Further, since the coating film on the resin substrate of the pulverized resin materials C is configured to be not softened under the softening point of the resin substrate in the coating-film peeling treatment, the coating film coated on the resin substrate can be peeled further surely. 
         [0121]    Also, since the larger material than the metal part has been removed from the untreated waste material for recycling prior to the pulverization treatment, burdens of apparatuses that work in the respective steps after the pulverization step can be properly lightened. 
         [0122]    Further, since the pulverized resin material without the coating film (OK articles C 1 ) is selected from the pulverized resin material with the coating film (NG articles C 2 ) in the coating-film-free resin-material selection treatment, a collection ratio of the pulverized resin material without the coating film can be further improved. 
         [0123]    The present invention should not be limited to the above-described embodiment, and any other modifications and improvements may be applied in the scope of a spirit of the present invention. 
         [0124]    For example, the pulverized resin materials C is comprised of plural kinds of pulverized resin materials that have similar softening points to each other. In this case, there is provided a conveyer apparatus to convey the pulverized resin materials C discharged from the outlet  75  to the hopper  74  again for the coating-film peeling apparatus  70  shown in  FIG. 2 . 
         [0125]    In this case, the CPU  202  drives the screw  72  at a state where the inner temperature of the cylinder  71  is set at the lowest softening point of the substrate when the pulverized resin materials C conveyed from the pulverized material selection apparatus  50  are supplied into the cylinder  71  from the hopper  74 . Thereby, the coating film of the pulverized resin materials having the lowest softening point of the substrate is peeled from the substrate. 
         [0126]    Next, the CPU  202  drives the above-described conveyer apparatus. Thereby, the pulverized resin materials C discharged from the outlet  75  are supplied into the cylinder  71  through the hopper  74 . 
         [0127]    Then, the CPU  202  sets the inner temperature of the cylinder  71  at the second lowest softening point of the substrate and drives the screw  72 . Thereby, the coating film of the pulverized resin materials having the second lowest softening point of the substrate is peeled from the substrate. 
         [0128]    Thus, the inner temperature of the cylinder  71  is increased stepwise up to the highest softening point of the substrate of the pulverized resin materials, and the treatment of the above-described coating-film peeling is repeated at each time of the stepwise increase of the temperature. Thereby, the coating films of all of the pulverized resin materials are peeled from their substrates. 
         [0129]    Also, there may be provided a treatment of melting the pulverized resin materials C without the coating film that has been removed after the coating-film-free material selection treatment by the coating-film-free material selection apparatus  90 . Thereby, since the material for remolding is obtained by melting the pulverized resin materials C without the coating film, the superior material for remolding in the physical properties or appearances can be obtained. In this case, a melting apparatus for the melting treatment and a conveyer apparatus from the coating-film-free material selection apparatus  90  to the melting apparatus are added to the system. The CPU  202  drives this conveyer to covey the pulverized resin materials C without the coating film from the coating-film-free material selection apparatus  90  to the melting apparatus and drives the melting apparatus to melt the pulverized resin materials C.