Resin dissolution device

Abstract

To provide a resin dissolution device effectively removing a resin material that CFRP contains.SOLUTION: A resin dissolution device 10 includes: a dissolution tank 30 reserving dissolution liquid 20 capable of dissolving a resin material adhering to carbon fibers of CFRP1; conveyance means conveying the CFRP1 so as to be immersed in the dissolution liquid 20 reserved in the dissolution tank 30; and a first reservation area and a second reservation area each provided inside the dissolution tank 30. The first reservation area reserves the dissolution liquid 20 before the resin material is dissolved while keeping the same within a prescribed concentration range. The second reservation area reserves the dissolution liquid 20 after the resin material is dissolved at the concentration of the dissolution liquid 20 in the first reservation area or lower together with a resin-derived component 21.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a resin dissolving device. [Background technology]

[0002] Carbon fiber reinforced plastic (CFRP) is a type of fiber reinforced composite material that contains carbon fiber and resin. The amount of CFRP used in industrial applications such as aircraft and automobiles is increasing, so recycling of CFRP is being considered. A method is known for recycling CFRP, in which the resin contained in used CFRP material is removed and the carbon fiber is recovered.

[0003] Patent Document 1 discloses a method for recovering carbon fibers from a carbon fiber composite cross-linked resin material, the method comprising: step (I) of contacting a carbon fiber composite cross-linked resin material containing carbon fibers and a cross-linked polyolefin resin with a treatment liquid containing concentrated sulfuric acid; step (II) of heating a mixture of the carbon fiber composite cross-linked resin material obtained in step (I) and the treatment liquid within a temperature range of not less than the glass transition temperature of the cross-linked polyolefin resin and less than 250°C; and step (III) of recovering carbon fibers from the mixture that has been subjected to step (II). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2011-074204 A Summary of the Invention [Problem to be solved by the invention]

[0005] In order to remove the resin material contained in the CFRP, a resin dissolving device may be used in which the CFRP is immersed in a dissolving liquid (treatment liquid) stored in a dissolving tank while being transported, thereby dissolving and removing the resin material. After the resin material contained in the CFRP is dissolved, the components derived from the resin material dissolved by the dissolving liquid are diffused, so the concentration of the dissolving liquid decreases. In addition, when the CFRP is immersed in the dissolving liquid while being transported, stirring occurs due to the flow of the dissolving liquid stored in the dissolving tank, so the concentration of the dissolving liquid tends to decrease uniformly. When the concentration of the dissolving liquid decreases, the dissolving performance of the dissolving liquid decreases. Therefore, there is a problem that such a resin dissolving device may not be able to sufficiently remove the resin material contained in the CFRP.

[0006] The present disclosure has been made to solve such problems, and has an object to provide a resin dissolving device that efficiently removes the resin material contained in CFRP. [Means for solving the problem]

[0007] A resin dissolving device according to one embodiment has a dissolving tank that stores a dissolving liquid capable of dissolving resin material adhering to carbon fibers of carbon fiber reinforced plastic, a transport means that transports the carbon fiber reinforced plastic so as to immerse it in the dissolving liquid stored in the dissolving tank, and a first storage area and a second storage area that are respectively provided inside the dissolving tank, wherein the first storage area stores the dissolving liquid before dissolving the resin material while maintaining the concentration within a predetermined range, and the second storage area stores the dissolving liquid after dissolving the resin material together with components derived from the resin material dissolved by the dissolving liquid at a concentration equal to or lower than the concentration of the dissolving liquid stored in the first storage area. Effect of the Invention

[0008] The present disclosure makes it possible to provide a resin dissolving device that efficiently removes resin material contained in CFRP. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a cross-sectional view showing a resin dissolving apparatus according to a first embodiment. [Diagram 2] FIG. 4 is a cross-sectional view showing a resin dissolving device according to a modified example of the first embodiment. [Diagram 3] FIG. 4 is a cross-sectional view showing a resin dissolving device of a comparative example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] First embodiment Hereinafter, an embodiment of the present disclosure will be described with reference to the drawings. However, the present disclosure is not limited to the following embodiment. In addition, in order to clarify the description, the following description and drawings are appropriately simplified. In the following description and drawings, the same or equivalent elements are given the same reference numerals, and duplicate descriptions are omitted.

[0011] First, a resin dissolving apparatus 10 according to a first embodiment will be described with reference to Fig. 1. Fig. 1 is a cross-sectional view showing the resin dissolving apparatus according to the first embodiment. As shown in Fig. 1, the resin dissolving apparatus 10 is an apparatus that dissolves and removes resin material contained in carbon fiber reinforced plastic (CFRP1) by using a dissolving liquid 20. Note that CFRP is an abbreviation for Carbon Fiber Reinforced Plastic.

[0012] The resin dissolving apparatus 10 can be applied to the removal process of a carbon fiber recycling method that includes, for example, an extraction process of extracting CFRP1 from used CFRP material, a removal process of removing resin material from the extracted CFRP1, and a winding process of winding up the carbon fiber obtained by removing the resin material.

[0013] The CFRP material has CFRP1 containing carbon fiber and a resin material. The CFRP material may be a product after molding (molded product) or an intermediate product before molding. The CFRP material is not particularly limited, but may be, for example, a tank which is a molded product. The tank is, for example, a hydrogen tank that can be used to fill a gas such as compressed hydrogen. The tank filled with compressed hydrogen is mounted on a fuel cell vehicle to supply hydrogen to the fuel cell.

[0014] The carbon fiber may be any material containing carbon as a main component. Examples of the carbon fiber include PAN (polyacrylonitrile)-based carbon fiber manufactured using polyacrylonitrile or pitch as a raw material, and PITCH-based carbon fiber. The carbon fiber may be surface-treated or may be provided with a sizing agent. The carbon fiber is preferably a continuous carbon fiber. In this embodiment, the carbon fiber contained in the CFRP1 is a fiber bundle of continuous carbon fiber.

[0015] The resin material may be a thermosetting resin or a thermoplastic resin. The resin material is not particularly limited, and examples thereof include phenol resin, urea resin, unsaturated polyester resin, vinyl ester resin, polyimide resin, bismaleimide resin, polyurethane resin, diallyl phthalate resin, epoxy resin, and mixtures thereof. The resin material may be used alone or in combination of two or more kinds. In the present embodiment, the resin material is an epoxy resin.

[0016] The resin dissolving apparatus 10 in this embodiment has a dissolving tank 30 that stores a dissolving liquid 20 capable of dissolving the resin material adhering to the carbon fibers of the CFRP 1, a plurality of guide rollers 40 that transport the CFRP 1 so as to be immersed in the dissolving liquid 20 stored in the dissolving tank 30, and a first storage section 51 and a second storage section 52 each provided inside the dissolving tank 30.

[0017] The resin dissolving device 10 continuously performs dissolving treatment by transporting the extracted CFRP 1 and immersing it in dissolving liquid 20 stored in a dissolving tank 30. When the resin material is dissolved using the dissolving liquid 20 in this manner, a component derived from the resin material dissolved by the dissolving liquid 20 (resin-derived component 21) is generated.

[0018] The dissolving liquid 20 is not particularly limited as long as it can dissolve the resin material contained in the CFRP 1, but it is preferable to use at least one liquid selected from, for example, an acidic solution, an alkaline solution, an organic solvent, a hydrogen peroxide solution, and an ionic liquid. These liquids can dissolve or swell the resin, and can efficiently remove the resin. The dissolving liquid 20 may be used alone or in combination of two or more kinds.

[0019] Examples of the acidic solution include a solution containing phosphoric acid, a solution containing sulfuric acid, etc. The acidic components such as phosphoric acid and sulfuric acid may be used alone or in combination of two or more.

[0020] Examples of the alkaline solution include a solution containing sodium hydroxide, a solution containing potassium hydroxide, etc. The alkaline components such as sodium hydroxide and potassium hydroxide may be used alone or in combination of two or more.

[0021] The type of organic solvent is not particularly limited, and examples thereof include alcohol-based solvents, ketone-based solvents, ether-based solvents, amide-based solvents, and ester-based solvents. The organic solvent may be used alone or in combination of two or more. The organic solvent may contain a decomposition catalyst such as an alkali metal compound.

[0022] Examples of the ionic liquid include ionic liquids containing at least one cation selected from imidazolium-based, pyridinium-based, pyrrolidinium-based, quaternary ammonium-based, and quaternary phosphonium-based cations. One type of ionic liquid may be used alone, or two or more types may be used in combination.

[0023] In this embodiment, the dissolving liquid 20 is an acidic solution in which sulfuric acid is dissolved in water. The dissolving liquid 20 containing sulfuric acid is preferable because it can dissolve the resin material well and is easily available. The concentration of the dissolving liquid 20 is not particularly limited, but is appropriately set depending on the type of dissolving liquid 20, the type of resin material, the thickness of the CFRP1, the temperature of the dissolving liquid 20, the dissolving process time, etc. From the viewpoint of enhancing the dissolving performance for dissolving the resin material, the higher the concentration of the dissolving liquid 20, the more preferable it is.

[0024] From the viewpoint of improving the dissolving performance, the dissolving liquid 20 is preferably heated, but may be at room temperature. The temperature of the dissolving liquid 20 containing sulfuric acid is preferably 60 to 200° C., for example. The dissolving process time differs depending on the type of dissolving liquid 20, the concentration and temperature of the dissolving liquid 20, the type of resin material, etc., but is, for example, about 2 seconds to 200 minutes. The dissolving process time can be adjusted, for example, by the conveying speed of the CFRP 1.

[0025] The dissolution tank 30 is a container made of a material that is not corroded by the dissolution liquid 20. For example, the dissolution tank 30 may be a container made of a corrosion-resistant material such as ceramic or resin, a metal container with at least the surface that comes into contact with the dissolution liquid 20 coated with a corrosion-resistant material such as ceramic or resin, or a metal container having corrosion resistance such as stainless steel. In this embodiment, the dissolution tank 30 is a metal container with the surface that comes into contact with the dissolution liquid 20 coated with Teflon ("Teflon" is a registered trademark). The size of the dissolution tank 30 is appropriately set depending on the dissolution processing time.

[0026] The dissolution tank 30 is open at the top. The dissolution tank 30 has a bottom wall 32 forming a bottom surface 31, a peripheral wall 33 extending upward from the edge of the bottom surface 31, and a partition wall 34 dividing the interior of the dissolution tank 30 into a first storage section 51 and a second storage section 52. The first storage section 51 and the second storage section 52 are arranged side by side in the conveying direction. The first storage section 51 is arranged upstream of the second storage section 52 in the conveying direction.

[0027] The first storage section 51 is a specific example of a first storage region that stores the dissolving liquid 20 before dissolving the resin material while maintaining it within a predetermined concentration range. In the case of the dissolving liquid 20 containing sulfuric acid, the predetermined concentration range of the dissolving liquid 20 stored in the first storage section 51 may be set to, for example, 80 to 98 mass %. The second storage section 52 is a specific example of a second storage region that stores the dissolving liquid 20 after dissolving the resin material together with the resin-derived component 21 at a concentration equal to or lower than that of the dissolving liquid 20 stored in the first storage section 51. That is, the concentration of the dissolving liquid 20 stored in the second storage section 52 is equal to or lower than that of the dissolving liquid 20 stored in the first storage section 51. In the case of the dissolving liquid 20 containing sulfuric acid, the lower limit of the concentration of the dissolving liquid 20 stored in the second storage section 52 may be set to, for example, 75 mass %. The size of the second storage section 52 is appropriately set according to the dissolving process time, the amount of the resin material to be dissolved, and the like.

[0028] Each guide roller 40 is formed using a material that is not corroded by the dissolving liquid 20. The material of each guide roller 40 may be, for example, a corrosion-resistant resin such as Teflon or polypropylene (PP), or a corrosion-resistant metal such as stainless steel. Each guide roller 40 may be, for example, a metal roller whose surface is coated with a corrosion-resistant resin. In this embodiment, each guide roller 40 is a Teflon roller formed using Teflon ("Teflon" is a registered trademark).

[0029] The guide rollers 40 are a specific example of a conveying means. The guide rollers 40 are arranged so that at least a part of them is immersed in the dissolving liquid 20 stored in the dissolving tank 30. The guide rollers 40 are arranged in parallel with each other at a required interval in the conveying direction. The conveying direction in which the CFRP 1 is conveyed is controlled in one direction by the guide rollers 40. The guide rollers 40 convey the CFRP 1 from the upstream to the downstream in the conveying direction with a predetermined tension, and immerse the CFRP 1 between the guide rollers 40 in the dissolving liquid 20. The resin dissolving device 10 shown in FIG. 1 has a guide roller 40 arranged in a first storage section 51 and a guide roller 40 arranged in a second storage section 52, but the number of guide rollers 40 is not limited to two, and may be, for example, three or more.

[0030] The tension applied to the CFRP 1 is controlled, for example, by a drive device (not shown) that drives the multiple guide rollers 40. The tension applied to the CFRP 1 can be adjusted, for example, by the peripheral speed of the multiple guide rollers 40. The tension applied to the CFRP 1 is set appropriately depending on the CFRP 1, and is preferably, for example, 1 to 50 N. If the tension is too low, problems may occur in the transportation of the CFRP 1. On the other hand, if the tension is too high, it may be difficult to impregnate the fiber bundle of the carbon fiber with the dissolving liquid 20. If it is difficult to impregnate the fiber bundle of the carbon fiber with the dissolving liquid 20, the resin material contained in the CFRP 1 cannot be sufficiently removed, and a defect may occur in which a residue of the resin material remains on the carbon fiber after the dissolution treatment.

[0031] Furthermore, the resin dissolving apparatus 10 has a tube 60 which is immersed in the dissolving liquid 20 stored in the dissolving tank 30 and through which the transported CFRP 1 passes. The tube 60 is made of a material that is not corroded by the dissolving liquid 20. In this embodiment, the tube 60 is a glass tube made of glass. The material of the tube 60 is not limited to glass as long as it is corrosion-resistant to the dissolving liquid 20, and may be, for example, a corrosion-resistant resin such as Teflon or polypropylene (PP), or a corrosion-resistant metal such as stainless steel.

[0032] The tube 60 is a cylindrical member extending in the conveying direction and has a size that allows it to be immersed in the dissolving liquid 20 stored in the dissolving tank 30. The tube 60 is disposed between the guide rollers 40 with at least a portion of the tube 60 immersed in the dissolving liquid 20 stored in the dissolving tank 30. The tube 60 is preferably immersed in the dissolving liquid 20 so that the inside of the tube 60 is filled with the dissolving liquid 20. This allows the dissolving liquid 20 to be appropriately brought into contact with the CFRP 1 passing through the inside of the tube 60.

[0033] In this embodiment, the tube 60 has a cylindrical shape with a circular cross section. However, the shape of the tube 60 is appropriately set according to the shape of the CFRP1 and the like. Therefore, the tube 60 is not limited to a cylindrical shape, and may have, for example, a rectangular tube shape with a polygonal cross section. In addition, the inner diameter of the tube 60 is larger than the outer diameter of the CFRP1 so that the CFRP1 can pass through the inside of the tube 60. The inner diameter of the tube 60 is not particularly limited as long as it is larger than the outer diameter of the CFRP1, but it is preferable that it is about 10 mm larger than the outer diameter of the CFRP1. If the inner diameter of the tube 60 is too small compared to the outer diameter of the CFRP1, the CFRP1 may come into contact with the tube 60 when passing through the inside of the tube 60, and some of the carbon fibers may be cut. On the other hand, if the inner diameter of the tube 60 is too large compared to the outer diameter of the CFRP1, the concentration of the dissolving liquid 20 tends to decrease inside the tube 60, so that the efficiency of removing the resin material may decrease.

[0034] An opening formed at one end of the pipe 60 is an inlet 61 through which the CFRP 1 is introduced. An opening formed at the other end of the pipe 60 is an outlet 62 through which the CFRP 1 is discharged. The pipe 60 is disposed inside the dissolution tank 30 along the conveying direction such that the inlet 61 is disposed on the upstream side and the outlet 62 is disposed on the downstream side. The length of the pipe 60 is set appropriately depending on the dissolution treatment time.

[0035] The dissolution tank 30 is preferably provided with at least one outlet 70 for discharging the mixture of the resin-derived component 21 stored in the second storage section 52 and the dissolution liquid 20 obtained after dissolving the resin material to the outside of the dissolution tank 30. The outlet 70 is provided with, for example, an opening / closing mechanism (not shown) for opening and closing the outlet 70. The mixture stored in the second storage section 52 is discharged to the outside of the dissolution tank 30 by the opening / closing mechanism opening the outlet 70. For example, when the dissolution liquid 20 stored in the second storage section 52 reaches a certain concentration (for example, 75 mass%), the opening / closing mechanism may open the outlet 70. The concentration of the dissolution liquid 20 can be measured using a concentration meter such as an electric conductivity meter.

[0036] The dissolution tank 30 shown in Fig. 1 has an outlet 70 provided at an end of the bottom wall 32 and an outlet 70 provided at a lower end of the peripheral wall 33, so that the outlets 70 are disposed at the most downstream positions of the dissolution tank 30. When discharging the mixture to the outside of the dissolution tank 30, the resin dissolution device 10 may have a dissolution liquid supply mechanism (not shown) that supplies, for example, new dissolution liquid 20 to the first storage section 51. When it is not necessary to discharge the mixture to the outside of the dissolution tank 30, the outlet 70 can be omitted.

[0037] Here, a resin dissolving apparatus 100 of a comparative example will be described with reference to Fig. 3. Fig. 3 is a cross-sectional view showing the resin dissolving apparatus of the comparative example. As shown in Fig. 3, the resin dissolving apparatus 100 of the comparative example has a dissolving tank 30b without a partition wall 34 instead of the dissolving tank 30. Moreover, the resin dissolving apparatus 100 does not have a pipe 60 and an outlet 70.

[0038] The resin dissolving apparatus 100 does not have a first storage region and a second storage region inside the dissolving tank 30b. Therefore, the dissolving tank 30b after dissolving the resin material contained in the CFRP 1 stores the dissolving liquid 20 before dissolving the resin material, the dissolving liquid 20 after dissolving the resin material, and the resin-derived component 21. When the dissolving process of the CFRP 1 is performed using the resin dissolving apparatus 100, after the resin material contained in the CFRP 1 is dissolved, the resin-derived component 21 is likely to diffuse and the overall concentration of the dissolving liquid 20 stored in the dissolving tank 30b is likely to decrease.

[0039] Furthermore, when the CFRP1 is immersed in the dissolving liquid 20 while being transported, stirring occurs due to the flow of the dissolving liquid 20 stored in the dissolving tank 30b, which promotes mixing inside the dissolving tank 30b and tends to reduce the concentration of the dissolving liquid 20 uniformly. Therefore, when the dissolving process of the CFRP1 is performed using the resin dissolving device 100, the concentration of the dissolving liquid 20 decreases as the dissolving process progresses, and the efficiency of removing the resin material decreases. Thus, there is a risk that the resin dissolving device 100 cannot sufficiently remove the resin material contained in the CFRP1.

[0040] Furthermore, since the resin-derived component 21 thickens the solution 20, when the CFRP1 is dissolved using the resin dissolving device 100, the solution 20 thickens as the dissolving process proceeds, making it difficult for the solution 20 to impregnate the fiber bundles of the carbon fibers. This can result in a failure to sufficiently remove the resin material contained in the CFRP1, resulting in a defect in which the resin material remains on the carbon fibers after the dissolving process. As a method for improving this, for example, it is possible to replace all of the solution 20 whose concentration has decreased with new solution 20, or to constantly supply new solution 20 to the inside of the dissolving tank 30b to control the concentration of the solution 20, but either method increases costs.

[0041] In contrast, when dissolving treatment of CFRP 1 is performed using the resin dissolving apparatus 10 according to this embodiment, the CFRP 1 is immersed in dissolving liquid 20 while being transported, so that dissolving liquid 20 flows in the transport direction from upstream to downstream. This generates a dissolving liquid flow F in which the dissolving liquid 20 in the first reservoir 51 flows into the inside of the pipe 60 from the inlet 61, and the dissolving liquid 20 in the pipe 60 flows out from the outlet 62 to the second reservoir 52. The dissolving liquid flow F generated in this way suppresses the mixture from flowing back inside the pipe 60.

[0042] While flowing from upstream to downstream inside the pipe 60, the dissolving liquid 20 comes into contact with the CFRP1 and dissolves the resin material. The resin-derived component 21 generated by the dissolving liquid 20 dissolving the resin material flows out from the inside of the pipe 60 to the second storage section 52 through the outlet 62 together with the dissolving liquid 20 after dissolving the resin material. In this way, the mixture is stored in the second storage section 52. The partition wall 34 suppresses the resin-derived component 21 from flowing from the second storage section 52 to the first storage section 51. Therefore, according to the resin dissolving device 10, the concentration of the dissolving liquid 20 stored in the first storage section 51 is suppressed from decreasing, so that the resin material contained in the CFRP1 can be efficiently removed. Furthermore, according to the resin dissolving device 10, the occurrence of defects caused by the thickening of the dissolving liquid 20 due to the inclusion of the resin-derived component 21 in the dissolving liquid 20 can be suppressed.

[0043] (Modification) Fig. 2 shows a cross-sectional view of a resin melting device which is a modified example of the first embodiment. In Fig. 2, three modified examples of the resin melting device 10 of the first embodiment are shown in Figs. 2(a) to 2(c). First, the first modified example, the first modified example, will be described with reference to Fig. 2(a). Fig. 2(a) is a cross-sectional view of the resin melting device which is the first modified example.

[0044] 2(a), the resin dissolving apparatus 10a, which is a first modified example, has a similar configuration to the resin dissolving apparatus 10, except that it has a dissolving tank 30a instead of the dissolving tank 30. Like the dissolving tank 30, the dissolving tank 30a has a peripheral wall 33 and a partition wall 34. And, instead of the bottom wall 32, the dissolving tank 30a has a bottom wall 32a that forms a bottom surface 31a that is inclined with respect to the horizontal direction so that the depth from the liquid level becomes deeper from the upstream to the downstream.

[0045] The inclination angle of bottom surface 31a is preferably, for example, 0 to 45°, and particularly preferably about 20°. When the inclination angle is within this range, resin-derived components 21 can be efficiently collected in the vicinity of outlet 70. On the other hand, when the inclination angle exceeds 45°, the depth from the liquid surface to bottom surface 31a becomes too deep, which increases the amount of dissolving liquid 20 used and drives up costs.

[0046] From the viewpoint of reducing the amount of dissolving liquid 20 used, it is preferable that such an inclination is adopted for a part of bottom surface 31a. Specifically, bottom surface 31a of second storage section 52 or a part of bottom surface 31a of second storage section 52 in the vicinity of outlet 70 is inclined with respect to the horizontal direction so that the depth from the liquid surface becomes deeper from the upstream to the downstream.

[0047] In addition, the resin dissolving apparatus 10, 10a does not necessarily have to include both the partition wall 34 and the pipe 60 as long as the first storage area and the second storage area are provided, and either one of them may be omitted. Therefore, a second modified example, which is another modified example of the first embodiment, will be described with reference to Fig. 2(b). Fig. 2(b) is a cross-sectional view showing the resin dissolving apparatus of the second modified example. In Fig. 2(b), the discharge port 70 is omitted.

[0048] As shown in Fig. 2(b), the resin dissolving apparatus 10b, which is the second modified example, does not have the pipe 60. The resin dissolving apparatus 10b is suitable for cases where it is possible to know in advance the resin dissolving start time, which indicates the time required from when the CFRP 1 comes into contact with the dissolving liquid 20 stored in the dissolving tank 30 until dissolution (decomposition) of the resin material begins. Since the resin dissolving apparatus 10b does not require the pipe 60, it is possible to simplify the structure of the apparatus and reduce costs.

[0049] The resin dissolution start time differs depending on the type of dissolving liquid 20, the concentration and temperature of the dissolving liquid 20, the type of resin material, etc., but is, for example, between about 15 seconds and 5 minutes. The dissolving process of CFRP1 using the resin dissolving device 10b will be described below by taking as an example a case where the resin dissolving start time is between t1 and t2 (for example, 1 to 2 minutes). In the resin dissolving device 10b, the conveying speed of the CFRP1 is set according to the resin dissolving start time. When the dissolving process of CFRP1 is performed using the resin dissolving device 10b, the CFRP1 passes through the first storage section 51 between t0 and t1, which is before the resin dissolving start time, and passes through the second storage section 52 between t1 and t2, which is after the resin dissolving start time. t0 is the time when the CFRP1 first comes into contact with the dissolving liquid 20 stored in the dissolving tank 30.

[0050] That is, the CFRP 1 passes through the first storage section 51 before the resin material starts to dissolve. Therefore, the first storage section 51 is configured to store the dissolving liquid 20 before the resin material dissolves, while maintaining the concentration within a predetermined range. The CFRP 1 passes through the second storage section 52 after the resin material starts to dissolve. Therefore, the second storage section 52 is configured to store the dissolving liquid 20 after the resin material has dissolved together with the resin-derived component 21 at a concentration equal to or lower than that of the dissolving liquid 20 stored in the first storage section 51.

[0051] When the resin dissolving apparatus 10b is used to dissolve the CFRP 1, the resin material contained in the CFRP 1 is dissolved in the second storage section 52. Therefore, a mixture of the resin-derived component 21 and the dissolving liquid 20 remaining after dissolving the resin material is stored in the second storage section 52. The partition wall 34 prevents the mixture containing the resin-derived component 21 from flowing from the second storage section 52 into the first storage section 51. Therefore, the resin dissolving apparatus 10b prevents a decrease in the concentration of the dissolving liquid 20 stored in the first storage section 51, and therefore the resin material contained in the CFRP 1 can be efficiently removed.

[0052] Next, a third modified example, which is another modified example of the first embodiment, will be described with reference to Fig. 2(c). Fig. 2(c) is a cross-sectional view showing a resin dissolving device according to the third modified example of the first embodiment. Note that in Fig. 2(c), the illustration of the discharge port 70 is omitted.

[0053] As shown in Fig. 2(c), the resin dissolving apparatus 10c according to the third modified example has a dissolving tank 30c without a partition wall 34. The resin dissolving apparatus 10c is suitable for the case where the specific gravity of the resin-derived component 21 is greater than that of the dissolving liquid 20. Since the resin dissolving apparatus 10c does not require the partition wall 34, the structure of the apparatus can be simplified and the cost can be reduced.

[0054] In the resin dissolving apparatus 10c, the upper layer 22 of the dissolving liquid 20 stored in the dissolving tank 30c is a specific example of a first storage region that stores the dissolving liquid 20 before dissolving the resin material while maintaining the concentration within a predetermined range. In the resin dissolving apparatus 10c, the lower layer 23 of the dissolving liquid 20 stored in the dissolving tank 30c is a specific example of a second storage region that stores the dissolving liquid 20 after dissolving the resin material together with the resin-derived component 21 at a concentration equal to or lower than that of the dissolving liquid 20 stored in the upper layer 22.

[0055] The pipe 60 of the resin dissolving device 10c is disposed in the upper layer 22. When the resin dissolving device 10c is used to perform dissolving treatment of the CFRP1, the dissolving liquid 20 in the upper layer 22 flows into the inside from the inlet 61, and the dissolving liquid 20 in the inside of the pipe 60 flows out from the outlet 62. Here, when the resin-derived component 21 is carbonized over time, the carbonized resin-derived component 21 precipitates in the dissolving liquid 20. Therefore, the resin-derived component 21 generated inside the pipe 60 flows out from the outlet 62 together with the dissolving liquid 20 after dissolving the resin material by the dissolving liquid flow F, and then precipitates. As a result, the precipitated resin-derived component 21 is mixed into the lower layer 23 after dissolving the resin material, while the resin-derived component 21 is prevented from being mixed into the upper layer 22 after dissolving the resin material. Therefore, according to the resin dissolving device 10c, the concentration of the dissolving liquid 20 in the upper layer 22 is prevented from decreasing, and therefore the resin material contained in the CFRP1 can be efficiently removed.

[0056] The present disclosure is not limited to the above-described embodiment, and may be modified as appropriate without departing from the spirit and scope of the present disclosure. In addition, the present disclosure may be implemented by appropriately combining the above-described embodiment and examples thereof. [Explanation of symbols]

[0057] 1 CFRP 10, 10a, 10b, 10c, 100 resin melting equipment 20 Dissolution solution 21 Resin-derived component 22 Upper layer 23 Lower layer 30, 30a, 30b, 30c dissolution tank 31, 31a bottom surface 32, 32a bottom wall 33 peripheral wall 34 partition wall 40 guide roller 51 first storage section 52 second storage section 60 Pipe 61 Inlet 62 Outlet 70 Outlet F Dissolved liquid flow

Claims

[Claim 1] A dissolving tank for storing a dissolving liquid capable of dissolving a resin material attached to the carbon fibers of the carbon fiber reinforced plastic; a conveying means for conveying the carbon fiber reinforced plastic so as to immerse the carbon fiber reinforced plastic in the dissolving liquid stored in the dissolving tank; a first storage area and a second storage area each provided inside the dissolution tank; having The first storage area is The solution before dissolving the resin material is stored while maintaining the solution within a predetermined concentration range; The second storage area is A resin dissolving device that stores the dissolving liquid after dissolving the resin material together with components derived from the resin material dissolved by the dissolving liquid at a concentration equal to or lower than the concentration of the dissolving liquid stored in the first storage area.

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