Resin recovery method

Abstract

The invention provides a resin recovery method, which is used for recovering resin from a waste vehicle and comprises the following steps of: disassembling the waste vehicle to obtain a waste vehicle waste material; the waste vehicle waste materials are crushed to obtain first scrapped chippings; wind screening is conducted on the first scrapped chippings, and first low-specific-gravity chippings and first high-specific-gravity chippings with the specific gravity higher than that of the first low-specific-gravity chippings are obtained; performing wet-type specific gravity screening on the first high-specific-gravity chippings, and further comprising the following steps: when the waste car is disassembled, taking down the interior parts containing fibers, and crushing the interior parts to obtain second scrapped chippings; and wind screening is conducted on the second scrapped chippings, and second low-specific-gravity chippings and second high-specific-gravity chippings with the specific gravity higher than that of the second low-specific-gravity chippings are obtained.

Description

Technical Field

[0001] The present invention relates to a method for recovering resin from scrapped vehicles. Background Art

[0002] In recent years, efforts to significantly reduce waste generation through prevention and reduction of waste generation, as well as recycling and reuse have been actively promoted. To achieve this, research and development of methods for recovering resin from scrapped vehicles is being carried out.

[0003] Patent document 1 describes a method for recycling scraps of used cars, which includes dismantling and crushing used cars, screening and removing harmful substances and valuables, and subjecting the obtained scraps to screening treatment in a series of scrap treatment steps, and selectively recovering foamed polyurethane or foamed plastics with it as the main constituent material from the scraps. The processing steps include a step of subjecting the scraps to screening treatment using the difference in the rebound force of the object and a step of subjecting a material group with relatively small rebound force to specific gravity screening treatment. As a method for specific gravity screening treatment, a wind screening treatment method is used.

[0004] Patent document 2 describes a method for screening crushed industrial waste, which uses gravity screening to screen out the crushed industrial waste after removing metals and glass to recover valuables. The method for screening crushed industrial waste consists of the following steps: a wind screening step, in the previous stage of the gravity screening step, the crushed industrial waste is not crushed but wind screened to separate light objects and heavy objects; and a gravity screening step, by immersing the heavy objects and light objects separated in the wind screening step separately in a screening liquid for gravity screening, and screening and removing chlorine-containing substances from the light objects or heavy objects. Among them, the crushed industrial waste is the crushed objects of metals removed after the scrapped vehicles with reusable parts removed are crushed by a car crusher.

[0005] [Prior Technical Literature]

[0006] (Patent Document)

[0007] Patent Document 1: Japanese Patent Application Publication No. 2003-236837

[0008] Patent Document 2: Japanese Patent Application Publication No. 2008-178846 Summary of the invention

[0009] [Problems to be solved by the invention]

[0010] However, in the methods described in Patent Documents 1 and 2, since the hard plastic containing the olefin resin is entangled with the fibers during wind screening, the recovery rate and recovery concentration of the olefin resin decrease as the amount of recovered low-density scraps increases. The low-density scraps are mainly used for heat recovery.

[0011] The object of the present invention is to provide a resin recovery method capable of improving the recovery rate and recovery concentration of olefin resins.

[0012] [Technical means to solve the problem]

[0013] (1) A resin recycling method for recycling resin from scrapped vehicles, comprising the following steps: dismantling the scrapped vehicles to obtain scrapped vehicle waste; crushing the scrapped vehicle waste to obtain first scrapped scraps; performing wind screening on the first scrapped scraps to obtain first low specific gravity scraps and first high specific gravity scraps having a higher specific gravity than the first low specific gravity scraps; performing wet specific gravity screening on the first high specific gravity scraps, further comprising: removing interior parts containing fibers when dismantling the scrapped vehicles, crushing the interior parts to obtain second scrapped scraps; and performing wind screening on the second scrapped scraps to obtain second low specific gravity scraps and second high specific gravity scraps having a higher specific gravity than the second low specific gravity scraps.

[0014] (2) The resin recovery method according to (1), wherein the first high specific gravity scraps are subjected to water specific gravity screening to obtain scraps having a specific gravity lower than 1 and scraps having a specific gravity greater than 1.

[0015] (3) The resin recovery method according to (2), wherein the scraps having a specific gravity of less than 1 contain an olefin-based resin.

[0016] (4) The resin recycling method according to any one of (1) to (3), wherein when the first scrapped scraps are obtained, the crushed scrapped car waste is subjected to magnetic screening to recover iron, and when the second scrapped scraps are obtained, the crushed interior parts are subjected to magnetic screening to recover iron.

[0017] (5) The resin recovery method according to any one of (1) to (4), further comprising the step of metal screening the first high specific gravity scraps to recover non-ferrous metals, and performing wet specific gravity screening on the first high specific gravity scraps after the metal screening.

[0018] (6) The resin recovery method according to any one of (1) to (5), wherein the air volume when the second scraps are subjected to wind screening is larger than the air volume when the first scraps are subjected to wind screening.

[0019] (Effects of the Invention)

[0020] According to the present invention, it is possible to provide a resin recovery method capable of improving the recovery rate and recovery concentration of olefin-based resins. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a figure explaining the resin recovery method which concerns on one embodiment of this invention.

[0022] Figure 2 It is a figure explaining the resin recovery method which concerns on one embodiment of this invention.

[0023] Figure 3 It is a figure explaining the resin recovery method which concerns on one embodiment of this invention.

[0024] Figure 4 This is a graph showing the relationship between the recovery concentration of the olefin-based resin in Example 1 and Comparative Example 1 and the recovery rate of the olefin-based resin. DETAILED DESCRIPTION

[0025] Hereinafter, the embodiments of the present invention will be described with reference to the drawings. Figures 1 to 3 , a resin recovery method according to one embodiment of the present invention is described.

[0026] The resin recycling method of this embodiment is a method for recycling resin from a scrap car 11. First, the scrap car 11 is dismantled to obtain scrap car scrap 12, but when the scrap car 11 is dismantled, the interior parts 13 containing fibers are removed (see Figure 1 ). As described below, since the removed interior parts 13 are crushed separately from the scrap car waste 12, the fiber content in the scrap obtained by crushing the scrap car waste 12 is reduced. As a result, when the scrap is wind-screened, the recovery rate and recovery concentration of the olefin resin are increased as the recovery amount of the low-specific-gravity scrap is reduced.

[0027] Among them, if the scrap car scrap 12 is crushed without removing the interior parts 13, or the removed interior parts 13 are crushed together with the scrap car scrap 12, when the scrapped scraps are wind-screened, as the recovery amount of the fiber-entangled low-specific gravity scraps increases, the recovery rate or recovery concentration of the olefin resin decreases.

[0028] The interior parts 13 are not particularly limited as long as they contain fibers, and examples thereof include carpets, dashboard insulators, seats, roof linings, and trunk floors. The fibers are not particularly limited, and examples thereof include nonwoven fibers and pulp fibers. The fiber length of the fibers is not particularly limited, and for example, is 15 mm to 100 mm.

[0029] When dismantling the scrap car 11, for example, the prime mover, power train, running parts, audio, radiator, wiring harness, etc. are removed. Before dismantling the scrap car 11, for example, freon gas for air conditioning, airbags, engine oil, transmission oil, cooling water, brake fluid, power steering fluid, fuel, and batteries are recovered.

[0030] Since the scrapped car waste 12 contains, for example, iron, non-ferrous metals (copper, aluminum, etc.), resins (olefin resins, rubber, etc.), and glass, the resins are recovered from the scrapped car waste 12 in the following manner (see Figure 2 ).

[0031] First, after the scrapped car scrap 12 is crushed, the crushed scrapped car scrap 12 is subjected to magnetic screening to recover iron 21, and a first scrapped scrap 22 is obtained. When the crushed scrapped car scrap 12 is subjected to magnetic screening, a well-known magnetic screening machine is used. Next, the first scrapped scrap 22 is subjected to wind screening to obtain a first low specific gravity scrap 23 and a first high specific gravity scrap 24 having a higher specific gravity than the first low specific gravity scrap 23. When the first scrapped scrap 22 is subjected to wind screening, a well-known wind screening machine is used. Next, after the first high specific gravity scrap 24 is subjected to metal screening to recover non-ferrous metal 25, the first high specific gravity scrap 24 after metal screening is subjected to water specific gravity screening to obtain scraps 26 having a specific gravity lower than 1 and scraps 27 having a specific gravity greater than 1. When the first high specific gravity scrap 24 is subjected to metal screening, a well-known metal screening machine is used. When the first high specific gravity chips 24 after metal screening are subjected to water specific gravity screening, a well-known wet specific gravity screening machine using water as a screening medium is used.

[0032] The scraps 26 having a specific gravity of less than 1 contain olefin resins, but the content of the olefin resins in the scraps 26 having a specific gravity of less than 1 is preferably 95% by mass or more, and more preferably 98% by mass or more. If the content of the olefin resins in the scraps 26 having a specific gravity of less than 1 is 95% by mass or more, the scraps 26 having a specific gravity of less than 1 can be chemically recycled without screening.

[0033] The crumbs 27 having a specific gravity of 1 or more contain rubber.

[0034] Furthermore, if necessary, the step of recovering iron 21 or the step of recovering non-ferrous metal 25 may be omitted. Furthermore, if necessary, the first high specific gravity scraps 24 after metal screening may be subjected to wet specific gravity screening using a screening medium other than water.

[0035] On the other hand, since the interior parts 13 contain, for example, iron and resin (plastic, fiber, etc.), the resin is recovered from the interior parts 13 in the following manner (see Figure 3 ).

[0036] First, after the interior parts 13 are crushed, the crushed interior parts 13 are subjected to magnetic screening to recover iron 31, thereby obtaining second scrapped scraps 32. When recovering iron 31, a well-known magnetic screening machine is used. Next, the second scrapped scraps 32 are subjected to wind screening to obtain second low specific gravity scraps 33 and second high specific gravity scraps 34 having a higher specific gravity than the second low specific gravity scraps 33. When the second scrapped scraps 32 are subjected to wind screening, a well-known wind screening machine is used. The resin contained in the second low specific gravity scraps 33 is depolymerized as needed.

[0037] The air volume when the second scrap 32 is wind-sorted is preferably larger than the air volume when the first scrap 22 is wind-sorted. Thus, as the amount of the second low-specific-gravity scrap 33 recovered increases, the recovery rate of the resin contained in the second low-specific-gravity scrap 33 increases.

[0038] Furthermore, the step of recovering the iron 31 may be omitted as necessary.

[0039] As mentioned above, although embodiment of this invention was described, this invention is not limited to the said embodiment, It is also possible to modify the said embodiment suitably within the range of the summary of this invention.

[0040] [Example]

[0041] Hereinafter, examples of the present invention will be described, but the present invention is not limited to the examples.

[0042] (Example 1)

[0043] use Figures 1 to 3 A resin recovery method is provided to recover resin from a scrap car. In this case, when dismantling the scrap car, the carpet, dashboard insulator, seat, roof lining, and trunk floor are removed as interior parts containing fibers. When dismantling the scrap car, the prime mover, power train, running parts, audio, radiator, wiring harness, etc. are also removed. Before dismantling the scrap car, Freon gas for air conditioning, airbags, engine oil, transmission oil, cooling water, brake fluid, power steering fluid, fuel, and batteries are recovered. The air volume when the first scrapped scraps are wind-screened and the air volume when the second scrapped scraps are wind-screened are set to 170A and 220A, respectively. As a result, the recovery amounts of the first low specific gravity scraps, the scraps with a specific gravity less than 1, the scraps with a specific gravity of 1 or more, and the second low specific gravity scraps are 17kg, 26kg, 50kg, and 34kg, respectively.

[0044] (Comparative Example 1)

[0045] The resin was recovered from one scrap car in the same manner as in Example 1 except that the removed interior parts were crushed together with scrap car waste. As a result, the recovery amounts of (first) low specific gravity scraps, scraps with a specific gravity of less than 1, and scraps with a specific gravity of 1 or more were 140 kg, 5 kg, and 5 kg, respectively.

[0046] From the above, it can be seen that when dismantling scrapped cars, the interior parts containing fibers are removed and crushed separately from the scrapped car waste. When the first scrapped debris is wind screened, as the recovery amount of the first high-specific gravity debris decreases, the recovery amount of debris with a specific gravity below 1 and debris with a specific gravity above 1 increases.

[0047] [Recovered concentration of olefin resin]

[0048] The content of olefin resin in the scraps with a specific gravity of less than 1 was measured as the recovery concentration of olefin resin in the following manner. First, the content of organic components in the scraps with a specific gravity of less than 1 was determined by elemental analysis (CHN analysis) and combustion ion chromatography (IC). Then, the content of olefin resin in the organic components was quantitatively analyzed by NMR.

[0049] [Recovery rate of olefin resin]

[0050] The recovery rate of the olefin-based resin was calculated based on the recovery amount of the scraps having a specific gravity of less than 1, the recovery concentration of the olefin-based resin, and the usage amount of the olefin-based resin used in the vehicle.

[0051] Figure 4 The relationship between the recovery concentration of the olefin resin in Example 1 and Comparative Example 1 and the recovery rate of the olefin resin is shown.

[0052] Depend on Figure 4 It is understood that Example 1 has a higher recovery rate and a higher recovery concentration of the olefin-based resin than Comparative Example 1.

[0053] Reference numerals

[0054] 11. Waste car

[0055] 12 Waste Cars and Scrap

[0056] 13 Interior parts

[0057] 21, 31 Iron

[0058] 22 First scrap debris

[0059] 23 First Low Specific Gravity Crumbs

[0060] 24 The first high specific gravity debris

[0061] 25 Non-ferrous metals

[0062] 26 Debris with a specific gravity below 1

[0063] 27 Debris with a specific gravity above 1

[0064] 32 Second scrap debris

[0065] 33 Second lowest specific gravity debris

[0066] 34 The second highest specific gravity debris

Claims

1. A resin recovery method is to recover resin from scrapped vehicles, comprising the following steps: Dismantling the aforementioned scrapped vehicles to obtain scrapped vehicle materials; Crushing the aforementioned scrap car waste to obtain first scrap debris; Performing wind screening on the first scrapped debris to obtain first low-specific-gravity debris and first high-specific-gravity debris with a specific gravity higher than that of the first low-specific-gravity debris; The first high specific gravity debris is subjected to wet specific gravity screening, Also includes: When dismantling the scrapped vehicle, removing the interior parts containing the fibers, and crushing the interior parts to obtain second scrapped scraps; and, The second scrapped debris is subjected to wind screening to obtain second low specific gravity debris and second high specific gravity debris having a higher specific gravity than the second low specific gravity debris.

2. The resin recovery method according to claim 1, wherein: The first high-specific-gravity debris is subjected to water-specific-gravity screening to obtain debris with a specific gravity lower than 1 and debris with a specific gravity higher than 1.

3. The resin recovery method according to claim 2, wherein: The chips having a specific gravity of less than 1 contain an olefin-based resin.

4. The resin recovery method according to any one of claims 1 to 3, wherein: When the first scrapped scrap is obtained, the crushed scrap car waste is subjected to magnetic screening to recover iron, When the aforementioned second scrap scraps are obtained, the aforementioned crushed interior trim parts are subjected to magnetic screening to recover iron.

5. The resin recovery method according to any one of claims 1 to 3, wherein: The method further comprises the step of screening the first high specific gravity scraps for metal to recover non-ferrous metals. The first high specific gravity scraps after the above metal screening are subjected to wet specific gravity screening.

6. The resin recovery method according to any one of claims 1 to 3, wherein: The air volume when the second scraps are screened by wind force is greater than the air volume when the first scraps are screened by wind force.

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