JP2012030467A - Method for recycling waste material of automobile resin - Google Patents

Abstract

The present invention provides a method for recycling a resin waste material for automobiles, which can provide a recycled resin material having good physical properties.
A recycling method for automobile resin waste material, in which foreign matters are removed from the resin resin waste material for automobiles having a coating film, and the resin material is recycled again as a new resin material. Coarse crushing process A for roughly crushing resin waste, metal removal process B for removing metal foreign matter from the coarse crushed material obtained by coarse crushing process A, and coarse crushed material after metal removal process B A pulverization step C for pulverization, and a foreign matter selection step D for selecting and removing residual foreign matters from the pulverized product obtained by the pulverization step. Further, at least after the coarse pulverization step A, the cyclic compound C ₅ H ₃ F _It has the coating-film removal process E which removes a coating film by ₇ , It is characterized by the above-mentioned. It is preferable to give mechanical external energy to the resin waste material during the coating film removing step E or immediately after the coating film removing step E.
[Selection] Figure 3

Description

  The present invention is a resin product for automobiles, which removes foreign matters from resin exterior waste materials and interior waste materials having a coating film removed from automobiles to be scrapped, and finally regenerates (recycles) them as new resin materials. The present invention relates to a method for recycling waste materials.

  In recent years, recycling has been actively promoted in various fields including PET bottles and rare metals. In the field of automobiles, recycling of plastic waste materials such as exterior materials such as bumpers, rocker moldings, air spoilers, license garnishes, and interior materials such as instrument panels, pillar garnishes, and side shields of seats is also being considered. In general, the surface of these automotive resin wastes often has a coating film for painting.

  As this type of regeneration method, for example, the techniques disclosed in Patent Document 1 and Patent Document 2 below are already known. These are crushed PP bumper waste material having a coating film to remove foreign matter, and then melted and kneaded with appropriate additives such as virgin resin (non-recycled resin) and talc, and finally, including the coating film. A pelletized recycled resin material is obtained.

Japanese Patent Laid-Open No. 2003-268175 JP-A-11-147223

  However, in Patent Document 1 and Patent Document 2, since the film including the coating film is regenerated, the physical properties of the recycled resin material are deteriorated. This limits the use of the recycled resin material and has a problem in practical use. In addition, it is essential to add a certain amount of a pearline material or the like in order to compensate for a decrease in physical properties due to the recycled resin. In addition, when obtaining a pelletized recycled resin material, it is necessary to continuously send out a molded product extruded into a fine string shape by an extruder to the next cutting step. There is also a risk that the item will be cut off. In this case, since the processing line stops each time, there is a problem that the processing efficiency is extended and the productivity is lowered.

  Accordingly, the present invention solves the above-described problem, and provides a method for recycling a resinous waste material for automobiles that can obtain a recycled resin material having good physical properties after removing a coating film from the resinous waste material for automobiles. provide.

As a means for that purpose, the present invention is a method for reclaiming automobile resin waste material by removing foreign matters from the resin waste material for automobiles having a coating film and regenerating again as a new resin material, comprising cyclic compound C _5. characterized in that the H ₃ F ₇ having a film removal step of removing the paint film. If the operation by the cyclic compound C ₅ H ₃ F _7, without degrading the resin substrate, the coating can only be accurately removed. The reason is not clear, but the molecular structure of the nonpolar resin substrate is not affected by the cyclic compound C ₅ H ₃ F ₇ which is a polar solvent, but only the molecular structure of the polar coating film is destroyed. It is thought that it is because it is done.

  According to this, since the coating film is removed in addition to the conventional foreign matter removal, it is possible to avoid deterioration of physical properties of the obtained recycled resin material. Therefore, some physical properties can be ensured without adding a virgin material as in the prior art. Even if a virgin material is added, the amount added can be reduced. In addition, the use as a member that could not be used with the conventional recycled resin material is expanded, and the practicality is improved. Moreover, even when it is obtained as a pelletized recycled resin material, the thin string-like molded product extruded from the extruder is difficult to cut halfway, and the productivity can be improved.

  Further, in the method for recycling automobile resin waste material according to the present invention, a rough crushing step for roughly crushing automotive resin waste material, and a metal for removing metal foreign substances from the coarsely crushed material obtained by the coarse crushing step It is preferable to include a removing step, a pulverizing step for pulverizing the coarsely crushed product after the metal removing step, and a foreign matter selecting step for selecting and removing residual foreign matter from the pulverized product obtained by the pulverizing step. According to this, metals other than a coating film and a foreign material can also be removed reliably. Therefore, the physical properties of the recycled resin material can be ensured more accurately. In addition, it is preferable to perform the coating film removing step at least after the rough crushing step. As long as it is at least after the rough crushing step, it may be before or after the crushing step. Further, it may be after the foreign matter sorting step or may be incorporated in the middle of the foreign matter sorting step. Although it is possible to perform the paint film removal process before the rough crushing process, a large processing tank is required to process the resin waste material obtained from the scrapped car without rough crushing, etc. The processing is difficult because of the large size and poor transportation efficiency. On the other hand, if the coating film removing process is performed after the rough crushing process, the coating film removing process is easy. Moreover, since it has a certain area (outside dimension), it is easy to separate and recover the removed coating film. Therefore, if fine pulverization is performed after the pulverization step, the coating film removal step is preferably performed before the fine pulverization step. This is because if the coating film removal step is performed after the resin waste material is finely pulverized, it is difficult to separate and recover the removed coating film.

Moreover, mechanical external energy is given to the resin waste material for automobiles during the coating film removal process (while removing the coating film with the cyclic compound C ₅ H ₃ F ₇ ) or immediately after the coating film removal process. It is preferable. Basically, the coating film is chemically peeled from the resin base material by the cyclic compound C ₅ H ₃ F ₇ , but in some cases, it cannot be completely peeled off and may remain. In this case, by applying mechanical external energy to the resin waste material, the coating film can be positively removed, and removal of the coating film can be prevented. However, aggressive removal by mechanical external energy is predicated on chemical action by the cyclic compound C ₅ H ₃ F ₇ . In addition, if mechanical external energy is also used, the processing time can be shortened.

  According to the present invention, a recycled resin material having good physical properties can be obtained from the waste resin material for automobiles, since it is recycled after removing the coating film in addition to the conventional foreign matter.

It is a schematic diagram which shows the first half line in the reproduction | regeneration facilities of PP waste materials. It is a schematic diagram which shows the latter half line in the reproduction equipment of PP waste materials. It is process drawing which shows the typical reproduction | regeneration process of PP waste materials. It is a data table showing the type and quantity of typical foreign substances contained in the bumper of scrap cars and the removal rate. It is a schematic diagram which shows the modification of the reproduction process of PP waste material. It is a schematic diagram which shows another modification of the reproduction | regeneration process of PP waste material. It is a schematic diagram which shows another modification of the reproduction | regeneration process of PP waste materials.

Hereinafter, typical embodiments according to the present invention will be described with reference to the drawings as appropriate. In this embodiment, as shown in FIG. 3, a rough crushing step A for roughly crushing resin waste materials for automobiles, a metal removing step for removing metal foreign matters from the coarsely crushed material obtained by the rough crushing step A B, crushing step C for crushing the coarsely crushed material after metal removal step B, foreign matter sorting step D for sorting and removing residual foreign matter from the crushed product obtained by crushing step C, and cyclic compound C ₅ H ₃ F _The film is regenerated through a coating film removing step E for removing the coating film by ₇ .

  Resin waste materials to be treated include resin exterior waste materials such as bumpers, rocker moldings, air spoilers, and license garnishes that have been removed from scrap cars, and resin panels such as instrument panels, pillar garnishes, and seat side shields. The interior waste material is not particularly limited as long as it has a coating film for color coating on the surface. These interior and exterior waste materials are typically made of polypropylene (PP), but some are made of acrylonitrile / butadiene / styrene copolymer resin (ABS) or made of copolymer resin of ABS and polycarbonate (PC). is there.

First, the resin waste material regeneration line will be described. The resin waste material is put into the cutting machine 10 of FIG. 1 as a roughly crushed material roughly crushed by a crusher outside the figure (coarse crushing step A). The coarsely crushed material here contains the typical foreign matter shown in FIG. 4 and the surface of the resin waste material is still coated. The coarsely crushed material discharged from the cutting machine 10 is transported by the magnetic conveyor 12 of the iron sorter in the metal removal step B, and the iron mixed in the coarsely crushed material is adsorbed and removed by the magnetic conveyor 12 (iron). Removal step B ₁ ). The roughly crushed material from which iron has been removed is transferred from the magnet conveyor 12 to the conveyor 13a and conveyed in one direction. At this time, the coarsely crushed material passes through the gate-type non-ferrous metal sorter 13 by the conveyor 13a, thereby generating an eddy current due to, for example, an electromagnetic induction phenomenon in a conductor such as aluminum, and using the associated kinetic force, the aluminum The nonferrous metal such as is selectively removed from the coarsely crushed material (nonferrous metal removal step B ₂ ).

The coarsely crushed material that has passed through the metal removing step B is sent to the pulverizing step C by the conveyor 14 while containing foreign substances other than metal and with a coating film attached. In the pulverization step C, the coarsely crushed material is pulverized by the pulverizer 15 installed in the soundproof chamber 15a, and the pulverized material discharged from the pulverizer 15 is conveyed to the foreign matter sorting step D by the air flow in the pipe passage 30. The In the foreign matter sorting step D, light foreign matters such as tapes are removed by the wind sorter 16 from the typical foreign matter shown in FIG. 4 (wind sorting step D ₁ ), and sand and residual metals are sorted by water specific gravity difference. 17 (specific gravity difference sorting step D ₂ ). Further, a coating film in which a solution containing the cyclic compound C ₅ H ₃ F ₇ as a main component is stored during the foreign matter sorting step D, specifically, between the wind sorting step D ₁ and the specific gravity difference sorting step D _2. It also has a coating film removal step E that removes the coating film by immersing the pulverized material in the removal tank 11. The pulverized material from which the coating film has been removed together with the foreign matters is sent to the cleaning / dehydrating machine 18 to remove the dirt (cleaning / dehydrating process F), and then the large particle size material sorting machine 19 exceeds the predetermined value. The pulverized product having a particle size is removed, and the particle size of the pulverized product is adjusted (granulation step G). Thus, after passing through the sizing step G, a crushed resin waste material in which the foreign matters and the coating film are removed and the particle size is adjusted is obtained.

The ground resin waste material sent out from the large particle size material sorter 19 is sent into the stock tank 20 of FIG. 2 by the air flow in the pipe passage 31. On the other hand, in the vicinity of the stock tank 20, a plurality of preparation hoppers 26 each containing various additive materials are provided. Although it does not specifically limit as an additive material, For example, 1 type, or 2 or more types chosen from a virgin material (non-recycled resin), a rubber material, a talc, a pigment, etc. are mentioned. These additive materials and pulverized resin waste are mixed and supplied to the twin screw extruder 22 by the individual material feeders 21 (mixing molding step H). In addition, when adding a virgin material, a rubber material, a talc, and a pigment as an additive material, in each material supply machine 21, the grinding | pulverization resin waste material is 50 to 90 weight%, and the sum total of a virgin material and rubber | gum is 5 to 40 weight%. The talc and the pigment are preferably mixed so that the total amount is 5 to 10% by weight. By mixing the pulverized resin waste material and the additive material at such a weight ratio, the specific gravity is 1.05 ± 0.02, the melt flow is 30 ± 10 g / 10 min, and the Charpy impact is 20 ± 10 KJ / m ² . Recycled resin having excellent physical properties. Further, by mixing the various additive materials and the pulverized resin waste immediately before being supplied to the twin screw extruder 22, the properties of the recycled resin become uniform.

  As is well known, the twin-screw extruder 22 has a structure in which parallel twin-screws are rotationally driven in a housing heated to a predetermined temperature. The mixed material of the pulverized resin waste material and the additive material supplied to the twin screw extruder 22 is melt-kneaded to form a paste, and is extruded from the twin screw extruder 22 through the separation filter 23. At this time, the paste-like mixed material is extruded into a plurality of fine string shapes after fine foreign matters having a particle size of about 100 μm are removed by the separation filter 23. The thin string-shaped molded product is continuously fed toward the cutting step I without being interrupted, and is cut into pellets by the cutting machine 24. The recycled resin pellets are fed into the product tank 25 by the air flow in the pipe passage 32 and stocked in the product tank 25.

As described above, the pulverized product pulverized in the pulverizing step C includes various foreign substances as shown in FIG. 4 in addition to the coating film. Therefore, in the foreign matter sorting process D, first, the light weight is removed by the wind sorter 16 (wind sorting process D ₁ ), and then the heavy object is removed by the water specific gravity difference sorting basket 17 (specific gravity difference sorting process D ₂ ). Thus, foreign matters can be efficiently removed. That is, when the water specific gravity difference sorting basket 17 is used first, a drying process is required before the wind power sorter 16 is used, so the efficiency is inferior.

Further, in this embodiment, to remove the coating with the wind sorting step D ₁ and the difference in specific gravity sorting step D ₂ (film removal step E). As the cyclic compound C ₅ H ₃ F ₇ solution used in the coating film removing step E, for example, ZEOLOR (registered trademark) H series manufactured by ZEON CORPORATION can be suitably used. If it is cyclic compound C ₅ H ₃ F ₇ , various types of urethane paints, acrylic paints, acrylic urethane paints and the like conventionally used as paints for automobiles are used without deteriorating the resin base material such as PP. The paint (coating film) can be removed. In the coating film removal step E, basically, the pulverized resin waste material may be simply immersed in the cyclic compound C ₅ H ₃ F ₇ solution. Thereby, a coating film peels from a base material. Although the coating film peeling process E can also be performed at normal temperature, in order to accelerate reaction, it is preferable to carry out by heating to about 30-90 degreeC. What is necessary is just to adjust immersion time suitably according to the kind and process temperature of a coating material.

The advantage of performing the coating film removing step E after the wind sorting step D ₁ is the same as the above advantage of performing the specific gravity difference sorting step D ₂ after the wind sorting step D ₁ . Further, by performing the coating removing step E before the difference in specific gravity sorting process D _2, it has the following advantages. That is, the pulverized product includes not only foreign substances but also fine powder of resin waste material generated in the pulverizing step C, and a coating film partially peeled off by pulverization. If this is sent to the water specific gravity difference sorting basket 17 as it is, the fine powder of the resin waste material is accumulated in the basket, and it is necessary to regularly remove the accumulated powder. In contrast, by performing the coating removing step E before the difference in specific gravity sorting process D _2, it is possible to solve such problems. Furthermore, since the pulverized product is exposed to the treatment solution in the coating film removing step E, if the coating film removing step E is performed before the cleaning / dehydrating step F, the processing can be efficiently performed. In addition, the foreign matter removal rate as a result of using the metal removal step B, the foreign matter sorting step D, and the separation filter 23 is as shown in the column “Removal rate” in FIG.

(Modification)
In the above embodiment has been film removal step E before the difference in specific gravity sorting process D _2, as shown in FIG. 5 may be performed after the difference in specific gravity sorting process D _2. In this case, since the performing film removal step E between the washing and dewatering step F and wind screening process D _1, it can be efficiently processed in the same manner as the above embodiment. Moreover, you may perform between the rough crushing process A and the crushing process C.

In the coating film removing step E, the coating film may not be completely peeled off depending on the case. Therefore, it is preferable to apply mechanical external energy to the pulverized product simultaneously with the coating film removing step E as shown in FIG. 6 or immediately after the coating film removing step E as shown in FIG. Thus, in addition to the chemical action of the cyclic compound C ₅ H ₃ F _7, it is possible to reliably remove the coating by mechanical energy. Examples of mechanical external energy include vibration, impact, and friction. In order to give vibration to the pulverized product, ultrasonic vibration can be given during the coating film removal step E, or it can be vibrated by a vibrator after the coating film removal step E. In order to give an impact to the pulverized product, shot blasting of the pulverized product after the coating film removing step E can be mentioned. In order to give friction to the pulverized product, the pulverized product can be stirred during the coating film removing step E, or can be stirred with a mixer after the coating film removing step E. Even in the case shown in FIG. 5, it is preferable to give mechanical external energy to the pulverized product during the coating film removing step E or immediately after the coating film removing step E.

  For example, when a specified pulverized product is collected from a specific supplier, the pulverized product can be directly supplied to the foreign matter sorting process D or the coating film peeling process E without going through the coarse crushing process A to the pulverizing process C. . The pulverized material in this case may be sent to a stock tank different from the stock tank 20 to be distinguished.

(Evaluation Test 1)
For coating removal by cyclic compound _C 5 _H 3 _{F 7,} to evaluate their effectiveness. As the cyclic compound C ₅ H ₃ F ₇ , Zeorora HTA manufactured by Nippon Zeon Co., Ltd. was used. As an evaluation sample, PP automobile bumper waste material cut into 5 cm square having various color coating films shown in Table 1 was used. The state of the coating film when these samples 1 to 6 were immersed in a sufficient amount of Zeolora HTA under the conditions shown in Table 1 was visually observed. The results are also shown in Table 1.

From the results in Table 1, it can be seen that various coating films can be removed accurately without changing the resin base material by the cyclic compound C ₅ H ₃ F ₇ . However, some of the coating films remained depending on the conditions as in Samples 4 to 6. Therefore, after crushing samples 4 to 6 and immersing them in 50 ° C. Zeolora HTA for 10 hours and then stirring with a commercially available mixer (National MX-X103), the crushed samples were rubbed together. Almost all the coating film could be removed. Thus, it was found that the coating film can be surely removed by applying mechanical energy. Moreover, from the results of Table 1, it was found that the immersion conditions are preferably higher in solution temperature and longer in immersion time.

(Evaluation test 2)
Next, physical properties of the resin regenerated from the resin waste material from which the coating film was removed by the cyclic compound C ₅ H ₃ F ₇ were evaluated. In the evaluation test, the ground resin waste material 100% with the coating film remaining (sample 7) and the ground resin waste material 100% with the cyclic compound C ₅ H ₃ F ₇ completely peeled off (sample 8) And PP virgin material 100% (sample 9) were molded into a plate shape having a size of 80 × 10 × 4 mm, and the Charpy impact values of the molded samples 7 to 9 were evaluated. The results are shown in Table 2. The Charpy impact value was determined in accordance with ISO 179, and the impact value at an impact head speed of 2.9 ± 10% (m / s) and a hammer head impact energy of 2.0 (J) was measured.

  From the results shown in Table 2, the physical properties of Sample 7 regenerated while leaving the coating film were greatly reduced compared to Sample 9 of 100% virgin material. On the other hand, Sample 8 that was regenerated by completely removing the coating film had the same physical properties as Sample 9.

DESCRIPTION OF SYMBOLS 10 Cutting machine 11 Coating film removal tank 12 Magnet conveyor 13 Non-ferrous metal sorter 15 Crusher 16 Wind sorter 17 Water specific gravity difference sorter 18 Washing / dehydrator 19 Large grain size sorter 20 Stock tank 21 Material supply machine 22 Shaft extruder 23 Separation filter 24 Cutting machine 26 Feeding hopper A Coarse crushing process B Metal removal process B ₁ Iron removal process B ₂ Nonferrous metal removal process C Grinding process D Foreign matter sorting process D ₁ Wind sorting process D ₂ Specific gravity difference sorting process E Coating removal process

Claims (3)

A method for recycling automobile resin waste material that removes foreign matters from automobile resin waste material having a coating film and regenerates it as a new resin material again,
A method for recycling a resin waste material for automobiles, comprising a coating film removing step of removing the coating film with a cyclic compound C ₅ H ₃ F ₇ . A rough crushing step for roughly crushing the automobile resin waste material,
A metal removal step of removing metal foreign matter from the coarsely crushed material obtained by the coarse crushing step;
A crushing step of crushing the coarsely crushed material after the metal removal step;
A foreign matter sorting step for sorting and removing residual foreign matter from the pulverized product obtained by the grinding step,
The method for recycling a resin waste material for an automobile according to claim 1, wherein the coating film removing step is included at least after the rough crushing step. The automotive resin product according to claim 1 or 2, wherein mechanical external energy is given to the automotive resin waste material during the coating film removing step or immediately after the coating film removing step. How to recycle waste materials.

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