Polymer resin recovery device

Abstract

The purpose of the present invention is to provide a novel polymer resin recovery device for recovering a polymer resin, for which degradation was suppressed, from a composite material containing the polymer resin. The present invention pertains to a polymer resin recovery device that processes a composite material containing a polymer resin with high-pressure hot water and recovers the polymer resin from the composite material, the device comprising: a heat treatment unit that accommodates the composite material and brings the composite material into contact with high-pressure hot water; a separation unit that is provided with a first filter member that allows through the polymer resin which melted in the heat treatment unit to pass while restricting the movement of the composite material and the movement of matter which did not melt in the heat treatment unit; and a water flow generation unit that sends a water flow to the separation unit.

Description

Polymer resin recovery equipment

[0001] The present invention relates to an apparatus for recovering a polymer resin from a composite material containing the polymer resin, and a method for recovering a polymer resin from a composite material containing the polymer resin using the apparatus.

[0002] In recent years, attention has been focused on the recycling of waste materials (resource recovery) from the viewpoint of reducing environmental impact. Methods for recycling polymer resins include chemical recycling, in which the resin is decomposed down to the monomers and repolymerized for reuse, and material recycling, in which the resin is melted and re-pelletized without being decomposed down to the monomers for reuse. However, material recycling is preferred from the viewpoint of energy costs.

[0003] As an apparatus for processing a composite material containing a polymer resin and recovering raw materials, for example, an apparatus is known which has, within a single closed space, a first hydrolysis section in which a material to be processed containing a polyester resin is exposed to a water vapor atmosphere to hydrolyze it, and a second hydrolysis section in which the obtained hydrolyzate is placed in hot water, heated, and further hydrolyzed (Patent Document 1).

[0004] JP 2015-172114 A

[0005] However, the device disclosed in Patent Document 1 recovers the polyester resin contained in the composite material as a hydrolyzate (specifically, terephthalic acid), and therefore, the device cannot recover a polymer resin with reduced degradation that is suitable for material recycling.

[0006] The present invention has been made in consideration of the above circumstances, and its object is to provide a new polymer resin recovery device that recovers polymer resin with suppressed deterioration from a composite material containing polymer resin.

[0007] The present invention, which has solved the above-mentioned problems, is as follows. [1] An apparatus for treating a composite material containing a polymer resin with high-pressure hot water and recovering the polymer resin from the composite material, the apparatus comprising: a heat treatment section that accommodates the composite material and brings it into contact with high-pressure hot water; a separation section that includes a first filter member that allows the polymer resin melted in the heat treatment section to pass while restricting the movement of the composite material and the movement of unmelted material in the heat treatment section; and a water flow generator that sends a water flow to the separation section. [2] The polymer resin recovery apparatus according to [1], which includes a cooling mechanism that cools the molten polymer resin separated in the separation section together with high-pressure hot water to solidify the polymer resin. [3] The polymer resin recovery apparatus according to [2], which includes a recovery section that recovers the solidified polymer resin. [4] The polymer resin recovery apparatus according to [3], which includes a second filter member in the recovery section that filters the solidified polymer resin. [5] The polymer resin recovery apparatus according to any of [1] to [4], which includes a hot water supply section that supplies hot water to the heat treatment section. [6] The polymer resin recovery apparatus according to [5], which has a hot water preparation mechanism upstream of the hot water supply unit. [7] The polymer resin recovery apparatus according to any one of [1] to [6], which has a heating mechanism in the heat treatment unit. [8] The polymer resin recovery apparatus according to any one of [1] to [7], wherein the water flow generating unit is a stirring blade provided in the heat treatment unit. [9] The polymer resin recovery apparatus according to any one of [1] to [8], which has a discharge unit that discharges the polymer resin melted in the heat treatment unit together with high-pressure hot water.

[10] The polymer resin recovery apparatus according to any one of [1] to [9], wherein the first filter member is detachable.

[11] The polymer resin recovery apparatus according to any one of [1] to

[10] , wherein the first filter member is made of metal.

[12] The polymer resin recovery apparatus according to

[11] , wherein the metal is made of at least one member selected from stainless steel and aluminum.

[13] The first filter member has a plurality of through holes (A), and the opening area per through hole (A) is 0.001 mm. 2 ~200cm 2

[14] The polymer resin recovery device according to any one of [1] to

[12] , wherein the second filter member has a plurality of through holes (B), and the opening area of ​​each of the through holes (B) is 0.001 mm 2 ~1cm 2

[15] The polymer resin recovery apparatus according to any one of [1] to

[14] , wherein the internal volume of the heat treatment section is 0.5 L to 3000 L.

[16] The polymer resin recovery apparatus according to [3], which has a plurality of the recovery sections.

[17] The polymer resin recovery apparatus according to [1], which has a plurality of the heat treatment sections.

[18] A method for recovering a polymer resin from a composite material containing a polymer resin, using the polymer resin recovery apparatus according to any one of [1] to

[17] .

[19] The method for recovering a polymer resin according to

[18] , wherein the composite material is an airbag fabric containing silicone, and the polymer resin is a polyamide-based resin or a polyester-based resin.

[20] A recycled product, at least part of whose raw material is a polyamide-based resin or a polyester-based resin obtained by the method according to

[19] .

[21] Use of the polymer resin recovery apparatus according to any one of [1] to

[17] , to recover a polymer resin from a composite material containing a polymer resin.

[22] Use of the polymer resin recovery device according to

[21] , wherein the composite material is an airbag fabric containing silicone, and the polymer resin is a polyamide-based resin or a polyester-based resin. [1a] An apparatus for treating a composite material containing a polymer resin with high-pressure hot water and recovering a polymer resin from the composite material, comprising: a treatment section that accommodates the composite material and brings it into contact with the high-pressure hot water, and through which the high-pressure hot water flows; a supply section that supplies the high-pressure hot water to the treatment section; a discharge section that discharges the polymer resin, together with the high-pressure hot water, melted by the high-pressure hot water supplied to the treatment section and separated from the composite material,

[0008] According to the present invention, a new polymer resin recovery device can be provided that recovers polymer resin with reduced degradation from a composite material containing the polymer resin. Furthermore, according to the present invention, a new polymer resin recovery device can be provided that optionally uses an alkaline aqueous solution when recovering polymer resin from a composite material, such as a polymer resin airbag fabric. According to the polymer resin recovery device of the present invention, the use of an alkaline aqueous solution in the treatment of the polymer resin airbag fabric can be eliminated or reduced, thereby suppressing damage (deterioration) of the polymer resin due to alkaline treatment. Preferably, according to the present invention, a new polymer resin recovery device can be provided that reduces the complexity of the polymer resin recovery operation.

[0009] Fig. 1 is a schematic diagram showing an example of a polymer resin recovery apparatus according to an embodiment of the present invention. Fig. 2 is a schematic diagram showing another example of a polymer resin recovery apparatus according to an embodiment of the present invention. Fig. 3 is a schematic diagram showing yet another example of a polymer resin recovery apparatus according to an embodiment of the present invention. Fig. 4 is a schematic diagram showing yet another example of a polymer resin recovery apparatus according to an embodiment of the present invention. Fig. 5 is a graph showing DSC curves of nylon 66 in air and water.

[0010] The present invention relates to an apparatus applicable to a method for treating a composite material containing a polymer resin with high-pressure hot water. Hereinafter, an apparatus applicable to a method for treating an airbag fabric, which uses a polyamide resin and / or a polyester resin (hereinafter also referred to as "polyamide-polyester") as the polymer resin, will be described as a representative example. However, the apparatus of the present invention can also be applied to composite materials other than the airbag fabric.

[0011] When an airbag fabric (composite material) made of polyamide / polyester (polymer resin) is treated with high-pressure hot water, the polyamide / polyester (polymer resin) melts in the water, while other components (e.g., silicone resin, etc.) that make up the airbag fabric (composite material) do not melt and remain as solids. The apparatus of the present invention is applicable to a method of recovering the molten polyamide / polyester (polymer resin) in the treatment liquid by filtering and separating it from the solids (e.g., silicone resin). Preferably, the apparatus is applicable to a method of cooling the treatment liquid containing the molten polyamide / polyester (polymer resin) that has been filtered and separated from the solids (e.g., silicone resin) to solidify the polyester / polyamide (polymer resin), and then recovering the solidified polymer resin. Also preferably, the apparatus is applicable to a method of recovering the solidified polymer resin by filtering.

[0012] The polymer resin recovery apparatus of the present invention is an apparatus capable of implementing the above-described polymer resin recovery method, and is characterized by having a heat treatment section that performs heat treatment with high-pressure hot water, a separation section equipped with a first filter member that allows the polymer resin melted in the heat treatment section to pass while restricting the movement of composite materials and unmelted materials (such as silicone resin) in the heat treatment section, and a water flow generating section that sends a water flow to the separation section. The polymer resin recovery apparatus of the present invention will be described below with reference to illustrative examples as necessary. However, the polymer resin recovery apparatus of the present invention is not limited by the illustrative examples below, and appropriate modifications can be made within the scope of the present invention, and all such modifications are within the technical scope of the present invention. Furthermore, the illustrative examples are schematic diagrams, and the proportions of the dimensions, etc., may differ from actual values.

[0013] FIG. 3 is a schematic diagram (schematic cross-sectional view) showing an example of a polymer resin recovery apparatus 12 of the present invention for carrying out the above-described method. The illustrated polymer resin recovery apparatus 12 includes a container-shaped heat treatment section 2a for containing a composite material 22, a separation section 2b composed of a first filter member 21, and a water flow generating section 8. The water flow generating section 8 is positioned so that the water flow generated by the water flow generating section 8 flows from the side where the composite material 22 is present to the side where the separation section 2b is present. In the heat treatment section 2a, the contained composite material 22 (e.g., airbag fabric) is contacted with high-pressure hot water for heat treatment, whereby the polymer resin (e.g., polyamide polyester) melts in the water, while other components (e.g., silicone resin) remain unmelted and remain as solids. In separation section 2b, first filter member 21 holds composite material 22 in water, and separates the molten polymer resin (hereinafter also referred to as molten polymer resin) from the solid matter by first filter member 21. Then, separation in separation section 2b is carried out efficiently by the water flow generated in water flow generating section 8.

[0014] In the polymer resin recovery apparatus 12 illustrated in FIG. 3, the separation section 2b is disposed inside the heat treatment section 2a, but the separation section 2b may be provided separately from the heat treatment section 2a. For example, a discharge section for discharging the molten polymer resin and high-pressure hot water from the heat treatment section 2a may be provided, and a separation section equipped with a first filter member may be provided downstream of the discharge section. When the separation section 2b is disposed inside the heat treatment section 2a, it is preferable that a portion of the heat treatment section 2a be separated by the first filter member 21, as illustrated in FIG. 3. Alternatively, a basket-shaped container with a lid may be provided inside the heat treatment section 2a, and the composite material 22 may be stored inside the basket-shaped container to serve as the first filter member 21.

[0015] 3, the water flow generating unit 8 is specifically an agitating blade 81 provided inside the heat treatment unit 2a. The agitating blade 81 is connected to a motor 141, and by rotating the agitating blade 81 with the motor 141, the water (hot water) inside the heat treatment unit 2a is rotated to generate a water flow.

[0016] 3 has a heating mechanism 23 in the heat treatment section 2a, and the heating mechanism 23 is specifically a heater provided on the outer bottom of the heat treatment section 2a. If the heat treatment section 2a is configured to be sealable, the water contained in the heat treatment section 2a can be heated by the heating mechanism 23 to become high-pressure hot water.

[0017] In the polymer resin recovery device 12 illustrated in Figure 3, the water flow in the separation section 2b provided inside the heat treatment section 2a (particularly the water flow hitting the composite material 22 inside the heat treatment section 2a) flows upward. Note that in this invention, the flow direction of the water flow includes not only the flow direction of laminar flow but also the flow direction of turbulent flow, and refers to the main direction of the entire flow whether it is laminar flow or turbulent flow. Furthermore, "upward" refers to the direction from the bottom of the water to the water surface (the direction against gravity).

[0018] The polymer resin recovery device 12 may further include at least one selected from the group consisting of a cooling mechanism, a pressurizing mechanism, a safety valve, a back-pressure valve, a pressure gauge, and a thermometer. The molten polymer resin separated in the separation section 2b can be solidified and recovered by stopping the heat treatment and leaving it alone, as the temperature in the heat treatment section 2a drops. The inclusion of the cooling mechanism allows the polymer resin to solidify more quickly, thereby more efficiently recovering the polymer resin 62 with reduced degradation. Examples of the pressurizing mechanism include a vacuum pump, a compressor, a boiler, and the like. The high-pressure hot water that contacts the composite material 22 in the heat treatment section 2a may be introduced from outside the heat treatment section 2a, or water (hot water) may be converted into high-pressure hot water within the heat treatment section 2a. The inclusion of the pressurizing mechanism (e.g., a steam boiler capable of introducing high-pressure steam into the heat treatment section 2a) makes it easier to convert water (hot water) into high-pressure hot water within the heat treatment section 2a. The inclusion of a pressure gauge and a thermometer makes it easy to confirm whether the water in the heat treatment section 2a is high-pressure hot water.

[0019] The polymer resin recovery apparatus of the present invention may include a hot water supply section 3 that supplies hot water to the heat treatment section 2a and a discharge section 4 that can discharge the molten polymer resin. FIG. 4 is a schematic diagram showing a polymer resin recovery apparatus 13 having the hot water supply section 3 and the discharge section 4. The heat treatment section 2a, separation section 2b, first filter member 21, water flow generating section 8, stirring blade 81, and motor 141 of the polymer resin recovery apparatus 13 illustrated in FIG. 4 are similar to those of the polymer resin recovery apparatus 12 illustrated in FIG. 3. The arrows in the flow path of the illustrated polymer resin recovery apparatus 13 indicate the direction of water flow. Because the polymer resin recovery apparatus 13 includes the discharge section 4, a separate operation to extract the solidified polymer resin 62 from the heat treatment section 2a is not required, making it easier to recover the polymer resin 62. In addition, the polymer resin recovery device 13 having the hot water supply section 3 and the discharge section 4 can further be provided with a back pressure valve, which can adjust the pressure within the heat treatment section 2a and turn the hot water within the heat treatment section 2a into high-pressure hot water.

[0020] In the polymer resin recovery device 13, heat treatment can be performed while supplying hot water into the heat treatment section 2a and / or while discharging the molten polymer resin and high-pressure hot water from the heat treatment section 2a. Alternatively, after supplying hot water to the heat treatment section 2a, heat treatment can be performed with the valve 123 provided in the hot water supply section 3 and the valve 124 provided in the discharge section 4 closed. When performing heat treatment while supplying hot water into the heat treatment section 2a, the pump 82 for supplying hot water also functions as the water flow generator 8. Specifically, as illustrated in FIG. 4, the hot water to be supplied to the heat treatment section 2a can be prepared by heating water contained in the water storage tank 9 using a heating mechanism 73 (e.g., a heater) provided in the hot water preparation mechanism 7a. As illustrated in FIG. 4, a check valve 131 upstream of the hot water supply section 3 is preferable because it prevents backflow of the treatment solution containing the molten polymer resin. The check valve 131 is particularly preferable when a backwashing mechanism (described later) is included.

[0021] When the direction of the water flow generated by the water flow generating unit 8 is upward, the discharge unit 4 may be configured to discharge the molten polymer resin and high-pressure hot water from the heat treatment unit 2a by overflow. Alternatively, a pump may be installed downstream of the discharge unit 4, and the molten polymer resin and high-pressure hot water may be discharged from the heat treatment unit 2a by the pump or the like.

[0022] In the polymer resin recovery apparatus 13 illustrated in FIG. 4 , the heating mechanism 23 capable of heating the heat treatment section 2a is specifically a jacket attached to the outer periphery of the heat treatment section 2a. When the heating mechanism 23 is a jacket, the jacket can also be designed to function as a cooling mechanism by using a refrigerant as the heat medium circulating inside the jacket. The polymer resin recovery apparatus 13 includes a cooling mechanism 5 as a container (specifically, a jacket tank) separate from the heat treatment section 2a. The polymer resin recovery apparatus may include the cooling mechanism 5 in the heat treatment section 2a or separately from the heat treatment section 2a. However, if the discharge section 4 is included, it is preferable to include the cooling mechanism 5 separately from the heat treatment section 2a in terms of recovery efficiency and deterioration prevention of the polymer resin 62. It is more preferable to include a container-type (e.g., jacket tank) cooling mechanism 5 separate from the heat treatment section 2a. In the cooling mechanism 5 of the polymer resin recovery apparatus 13, the molten polymer resin flowing from the discharge section 4 is cooled and solidified.

[0023] When the cooling mechanism 5 is a container-type cooling mechanism, the recovery section 6 that recovers the solidified polymer resin 62 may be a container-type inner tank contained in the container that is the cooling mechanism 5. Recovery in the recovery section 6 may be configured to allow the solidified polymer resin 62 to settle naturally or to be filtered using a filter member (a second filter member, described later). The recovery section 6 may also be a centrifuge, which may be equipped with a conventional cooling mechanism 5. The polymer resin recovery apparatus 13 has a jacket tank composed of the cooling mechanism 5 that is a jacket and the recovery section 6 that is an inner tank. In the recovery section 6, the solidified polymer resin 62 settles naturally, and water is discharged by overflowing from the recovery section 6, thereby recovering the polymer resin 62. In the polymer resin recovery apparatus 13, the discharge by overflow is configured to be performed by a valve 125. If the recovery section 6 is a container-type cooling mechanism and configured to recover the solidified polymer resin 62 by natural precipitation, the polymer resin recovery apparatus can be an apparatus that is easy to maintain. When the recovery unit 6 is a container type and is configured to recover the solidified polymer resin 62 by natural precipitation, a flow-regulating wall may be provided in the recovery unit 6 from the viewpoint of efficiently recovering the polymer resin 62. Water may be discharged from the recovery unit 6 by extraction using a pump, and from the viewpoint of maintainability of the device, discharge by overflow is preferred.

[0024] The polymer resin recovery apparatus 13 is configured to include a recovered water storage tank 91 for storing water discharged from the recovery unit 6. Storage of water discharged from the recovery unit 6 facilitates reuse of the water. For example, the recovered water storage tank 91 can be connected to the water storage tank 9 or the heat treatment unit 2a via piping, allowing the recovered water to be reused for polymer resin recovery. When the recovered water is reused, the polymer resin recovery apparatus preferably has a configuration (filter member, centrifuge, etc.) for filtering, separating, or otherwise treating the recovered water before reuse. Even when the water in the recovered water storage tank 91 is not reused and is instead discharged, it is preferably configured for appropriate filtering, separation, or other treatment (filter member, centrifuge, etc.) from the perspective of environmental protection, etc.

[0025] 1 is a schematic diagram showing another example of a polymer resin recovery apparatus of the present invention for carrying out a method of recovering molten polyamide polyester (polymer resin) in a heat treatment solution by filtering and separating it from solids (such as silicone resin) in a molten state. The arrows in the flow paths of the illustrated polymer resin recovery apparatus 1 indicate the direction of water flow. The illustrated polymer resin recovery apparatus 1 includes a container-shaped heat treatment section 2a for containing a composite material 22, a water flow generation section 8 and a hot water supply section 3 provided upstream of the heat treatment section 2a, and a discharge section 4, a cooling mechanism 5, and a recovery section 6 provided downstream of the heat treatment section 2a. The heat treatment section 2a is provided with a separation section 2b equipped with a first filter member 21, and the recovery section 6 is provided with a second filter member 61. The heat treatment unit 2a is a device that processes a composite material 22 (e.g., airbag fabric) using high-pressure hot water flowing through it. This process melts the polymer resin (e.g., polyamide polyester) in the water, while other components (e.g., silicone resin) remain unmelted as solids. The high-pressure hot water flows through the heat treatment unit 2a due to a water flow generated by a water flow generator 8, which is a pump. A first filter member 21 in the separation unit 2b provided within the heat treatment unit 2a retains the composite material 22 in the water and separates the molten polymer resin from solids (specifically, the composite material 22 and any unmelted material from the heat treatment). The polymer resin is then discharged together with the high-pressure hot water from the discharge unit 4. After discharge, the polymer resin and high-pressure hot water are cooled by a cooling mechanism 5, and the polymer resin solidifies in the water. The recovery unit 6 separates the solidified polymer resin 62 from the cooled water and recovers the polymer resin 62. The solidified polymer resin 62 is filtered out by a second filter member 61 provided in the recovery section 6. In the example shown in Fig. 1, a container-type cooling mechanism 5 (e.g., a jacket tank) is used as the cooling mechanism, and the container-type recovery section 6 is housed within the cooling mechanism 5. This reduces the risk of line blockage even if a large amount of polymer resin solidifies due to the cooling mechanism 5.

[0026] 1 is equipped with a hot water supply section 3 and a water flow generator 8 for supplying high-pressure hot water to the heat treatment section 2a, allowing the high-pressure hot water to flow through the heat treatment section 2a from the hot water supply section 3 toward the discharge section 4. Even when the high-pressure hot water is flowing, the first filter member 21 provided in the separation section 2b provided in the heat treatment section 2a restricts the movement of the composite material 22 (i.e., the first filter member 21 acts as a submerged holding member for holding the composite material 22 in the water, thereby holding the composite material 22 within the heat treatment section 2a), allowing the composite material 22 to be continuously treated with the high-pressure hot water, thereby further improving treatment efficiency.

[0027] In the polymer resin recovery apparatus 1 illustrated in Figure 1, a high-pressure hot water preparation mechanism 7b for generating high-pressure hot water is connected to the hot water supply unit 3, allowing high-pressure hot water to be supplied from the hot water supply unit 3. The high-pressure hot water preparation mechanism 7b is composed of a pressure adjustment mechanism 71 and a heating mechanism 72. In the illustrated example, the heating mechanism 72 is a heater that can be monitored by a thermometer (not shown). The pressure adjustment mechanism 71 in the illustrated example is a pressure adjustment valve equipped with a pressure control device (not shown) that can be monitored by a pressure gauge (not shown).

[0028] In the polymer resin recovery apparatus 1 illustrated in FIG. 1 , the liquid after removing the polymer resin 62 in the recovery section 6 can be stored in the water storage tank 9 after passing through residue removal filters 111 and 112 to remove fine residue as needed. Therefore, the filtrate from which the polymer resin 62 has been filtered can be appropriately treated in the water storage tank 9 and then removed as wastewater. The polymer resin recovery apparatus 1 illustrated in FIG. 1 also has three-way valves 121 and 122 on the upstream and downstream sides of the residue removal filters 111 and 112, respectively. By appropriately switching the flow paths of the valves 121 and 122, it is possible to switch between a mode in which only the residue removal filter 111 flows and a mode in which only the residue removal filter 112 flows. Therefore, by switching the residue removal filter that flows before the residue removal filter becomes clogged, it is possible to appropriately treat (e.g., replace or clean) the residue removal filter on the side where the flow is stopped while the apparatus is continuously operating. In the illustrated example, the water stored in the water storage tank 9 can also be used as raw water for high-pressure hot water. Specifically, the water stored in the water storage tank 9 can be sent to the high-pressure hot water preparation mechanism 7b by a liquid sending device (a pump 82 in the illustrated example).

[0029] In the polymer resin recovery apparatus 1 of the present invention, the time the polymer resin is exposed to high pressure and high temperature is shortened by contacting the composite material 22 with high-pressure hot water through a flow, and by promoting separation in the separation section 2b by the water flow rather than retaining the molten polymer resin within the heat treatment section 2a, and then discharging the polymer resin from the heat treatment section 2a and subsequently cooling and solidifying it using the cooling mechanism 5. This further suppresses deterioration of the recovered polymer resin 62. Furthermore, because the water flow is used to transport the polymer resin from the heat treatment section 2a to the recovery section 6, the polymer resin 62 can be separated and recovered from the composite material 22 easily without complicated operations. In a batch-type hydrolysis treatment apparatus such as that disclosed in Patent Document 1, even if an attempt is made to shorten the time the treated material is exposed to high pressure and high temperature, it is not possible to achieve the same shortening of the time as with the apparatus of the present invention, because it takes time to heat / pressure and cool / depressure the treatment tank containing the treated material. For this reason, in a batch-type hydrolysis treatment apparatus such as that disclosed in Patent Document 1, deterioration (e.g., hydrolysis) of the polymer resin progresses even during temperature / pressure increase and temperature / pressure decrease, making it difficult to recover a polymer resin suitable for material recycling.

[0030] In the polymer resin recovery apparatus of the present invention, the recovery section may be provided separately from the cooling mechanism. FIG. 2 is a schematic diagram showing a polymer resin recovery apparatus 11 in which the recovery section 6 is provided separately from the cooling mechanism 51. The polymer resin recovery apparatus 11 illustrated in FIG. 2 is similar to the polymer resin recovery apparatus 1 illustrated in FIG. 1 except for the recovery section 6 and the cooling mechanism 51. The arrows in the flow paths of the illustrated polymer resin recovery apparatus 11 indicate the direction of water flow. In the polymer resin recovery apparatus 11, a flow-path cooling mechanism 51 (e.g., a multi-tube heat exchanger) is provided upstream of the recovery section 6. By providing the cooling mechanism 51 upstream of the recovery section 6, the polymer resin can be more reliably solidified before passing through the recovery section 6, thereby improving the recovery efficiency of the polymer resin. Furthermore, the polymer resin recovery apparatus of the present invention may have a first cooling mechanism upstream of the recovery section and a second cooling mechanism that houses the recovery section. Having both the first and second cooling mechanisms allows for more efficient polymer resin recovery.

[0031] Recovery of polymer resin using the polymer resin recovery device of the present invention has high thermal treatment efficiency, making it possible to reduce the processing time required for thermal treatment and suppress deterioration of the polymer resin 62. Furthermore, when recovering polymer resin using the polymer resin recovery device of the present invention, the presence of the separation section 2b allows the molten polymer resin to be separated from the composite material 22 and any unmelted material from the thermal treatment, making it easy to recover the polymer resin 62. Without separation of the molten polymer resin in the separation section 2b, the polymer resin 62 solidified by cooling may become attached to the unmelted material, making the recovery process complicated. Furthermore, recovery of polymer resin using the polymer resin recovery device of the present invention allows the recovery of polymer resin 62 without the need for alkali treatment of the composite material 22 (e.g., airbag fabric). This avoids deterioration of the polymer resin 62 due to alkali treatment and allows the polymer resin 62 to be easily separated and recovered from the composite material 22 without complicated operations. Polymer resin recovery devices 12 and 13 are preferred in that they are easy to maintain and can produce polymer resin 62 in which deterioration is suppressed simply and efficiently, while polymer resin recovery devices 1 and 11 are preferred in that they can produce polymer resin 62 in which deterioration is suppressed efficiently in a shorter time.

[0032] In the polymer resin recovery device of the present invention, the heat treatment section and the recovery section may each independently be container-shaped or cylindrical. The heat treatment section 2a is preferably pressure-resistant, and its internal volume is preferably 0.5 L to 3000 L, more preferably 1 L or more, even more preferably 2 L or more, even more preferably 5 L or more, more preferably 1500 L or less, even more preferably 1200 L or less, even more preferably 1000 L or less, and even more preferably 800 L or less. That is, the internal volume of the heat treatment section 2a is more preferably 1 L to 1500 L, even more preferably 2 L to 1200 L, even more preferably 5 L to 1000 L, and even more preferably 5 L to 800 L. By having the internal volume of the heat treatment section 2a within the above range, the polymer resin 62 can be more efficiently recovered from the composite material 22.

[0033] The heat treatment section 2a is preferably a vessel-type, as exemplified in FIGS. 1 to 4 , and is more preferably a pressure vessel because it is a place where heat treatment is performed with high-pressure hot water. When the heat treatment section 2a is a vessel-type, it may be a vertical or horizontal vessel, and may have a lid that can close the opening of the vessel. From the viewpoint of improving the efficiency of heat treatment, a vertical vessel is preferred in a configuration in which the flow direction of the water flow generated by the water flow generating section 8 is primarily upward or downward, and a horizontal vessel is preferred in a configuration in which the flow direction of the water flow generated by the water flow generating section 8 is primarily horizontal. When the heat treatment section 2a is a cylindrical vessel-type, in order to concentrate the water flow generated by the water flow generating section 8 in one direction, the ratio of the diameter of the vessel to the length of the vessel is preferably 2 times or more, more preferably 3 times or more, even more preferably 3.5 times or more, even more preferably 4 times or more, particularly preferably 4.5 times or more, and most preferably 5 times or more. There is no particular upper limit to the ratio of the diameter to the length of the vessel, but in the case of a vessel equipped with an agitating blade or a tank-shaped vessel, it may be 10 times or 20 times. In this case, the vessel may be vertical or horizontal, but in the case of a vessel equipped with an agitating blade, a vertical type is preferred. The heat treatment section 2a may be a piping-type vessel such as a tube reactor or a reaction tube. In the case of a piping-type vessel, the upper limit may be 100 times, 300 times, 500 times, or 1000 times. In the case of a piping-type vessel, it is preferable that the vessel be U-shaped, N-shaped, Z-shaped, or a bent shape that repeats these, a coil shape, or a spiral shape. In the case of a vertical vessel with an oval-spherical bottom, the length of the vessel is the length from the bottom to the water level, and the diameter of the vessel is the diameter from the part excluding the bottom to the water level. In cases where the diameter of the vessel gradually increases or decreases, or in the case of a barrel shape, etc., where it is not a perfect cylinder, the arithmetic mean diameter is used. In the case of a piping-type vessel, the diameter and length of the vessel are the diameter and length of the piping.

[0034] Furthermore, when a water flow generator 8 such as an agitator blade is present inside the vessel of the heat treatment unit 2a, the distance between the water flow generator 8 and the first filter element 21, or when a water flow generator 8 such as a pump is present outside the vessel of the heat treatment unit 2a, the distance between the inlet for introducing the water flow into the vessel of the heat treatment unit 2a and the first filter element 21, is preferably expressed as the ratio of the diameter to the length of the vessel, where the distance is the distance between the two closest points. By achieving this relationship, a stable, unidirectional water flow can be achieved.

[0035] In the polymer resin recovery apparatuses 1 and 11, the heat treatment section 2a is provided with an opening A (not shown) upstream of the first filter member 21 and a lid A (not shown) that can openably and closably close the opening A, and the object to be treated (composite material 22) can be introduced and recovered through the opening A. The heat treatment section 2a itself may be configured to be detachable from the polymer resin recovery apparatuses 1 and 11, and this detachability allows for easier introduction and recovery of the composite material 22.

[0036] The composite material 22 introduced into the heat treatment section 2a may be introduced in its original shape, but from the viewpoint of the efficiency of the heat treatment, it is preferable to introduce the composite material 22 into the heat treatment section 2a in a size of 2500 cm. 2 If it is more than 1 mm 2 ~2500cm 2 It is preferable to cut or crush the composite material 22 into pieces within the range of 25 mm. 2 More preferably, 1 cm or more 2 More preferably, 10 cm or more 2 More preferably, 1500 cm 2 More preferably, 1000 cm or less 2 More preferably, the composite material 22 has a size of 25 mm or less. 2 ~1500cm 2 More preferably, 1 cm 2 ~1000cm 2 is more preferable, and 10 cm 2 ~1000cm 2is even more preferable. From the viewpoint of heat treatment efficiency, the size of the composite material 22 is preferably within a range of 1 mm to 500 mm in length and 1 mm to 500 mm in width, and more preferably within a range of 5 mm to 450 mm in length and 5 mm to 450 mm in width. The shape of the composite material 22 is not particularly limited, and may be a quadrilateral such as a rectangle or square, a circle, an ellipse, or other polygonal shape, or an irregular shape, with a quadrilateral shape being preferable from the viewpoint of handleability.

[0037] In the present invention, high-pressure hot water refers to water having a temperature of 100° C. or higher and a pressure equal to or higher than the saturated water vapor pressure at that temperature. The temperature and pressure of the high-pressure hot water may be any temperature and pressure that can melt the polymer resin contained in the composite material 22.

[0038] When the composite material 22 contains polyamide polyester as the polymer resin, the temperature of the high-pressure hot water during heat treatment in the heat treatment section 2a (i.e., the treatment temperature of the composite material 22; in the polymer resin recovery devices 1, 11, the temperature of the high-pressure hot water flowing through the heat treatment section 2a) is preferably 160°C or higher, more preferably 170°C or higher, even more preferably 175°C or higher, even more preferably 180°C or higher, even more preferably 185°C or higher, even more preferably 188°C or higher, and particularly preferably 190°C or higher. Furthermore, from the viewpoint of suppressing degradation of the polymer resin, the temperature of the high-pressure hot water during heat treatment in the heat treatment section 2a is preferably 250°C or lower, more preferably 240°C or lower, even more preferably 235°C or lower, and even more preferably 230°C or lower. That is, the temperature of the high-pressure hot water is preferably 160° C. to 250° C., more preferably 170° C. to 240° C., even more preferably 175° C. to 235° C., even more preferably 180° C. to 230° C., even more preferably 185° C. to 230° C., even more preferably 188° C. to 230° C., and particularly preferably 190° C. to 230° C. If the temperature of the high-pressure hot water is within the above range, the polymer resin 62 with reduced degradation can be recovered with high efficiency.

[0039] When the composite material 22 contains polyamide polyester as the polymer resin, the pressure of the high-pressure hot water during heat treatment in the heat treatment section 2a (i.e., the treatment pressure of the composite material 22; in the polymer resin recovery devices 1, 11, the pressure of the high-pressure hot water flowing through the heat treatment section 2a) is preferably 1.0 MPa to 4.0 MPa, more preferably 1.1 MPa or more, even more preferably 1.2 MPa or more, more preferably 3.6 MPa or less, even more preferably 3.3 MPa or less, even more preferably 3.0 MPa or less, and even more preferably 2.8 MPa or less. That is, the pressure of the high-pressure hot water is more preferably 1.1 MPa to 3.6 MPa, even more preferably 1.2 MPa to 3.3 MPa, even more preferably 1.2 MPa to 3.0 MPa, and even more preferably 1.2 MPa to 2.8 MPa. If the pressure of the high-pressure hot water is within the above range, the polymer resin 62 with suppressed degradation can be recovered with high efficiency. By setting the temperature and pressure as described above, the composite material 22 such as an airbag fabric can be heat-treated under a pressure equal to or greater than the saturated water vapor pressure, and the heat-treatment can be performed while the entire composite material 22 is kept immersed in water by the underwater holding member represented by the first filter member 21, thereby enabling efficient recovery of the polymer resin.

[0040] When composite material 22 contains a polyamide resin (particularly nylon 66) as the polymer resin, it is preferable that the temperature of the high-pressure hot water during heat treatment in heat treatment section 2a be 180°C to 240°C and the pressure of the high-pressure hot water during heat treatment in heat treatment section 2a be 1.0 MPa to 3.6 MPa, from the viewpoints of improving the recovery rate and suppressing deterioration of polymer resin 62. Furthermore, when composite material 22 contains a polyester resin (particularly polyethylene terephthalate) as the polymer resin, it is preferable that the temperature of the high-pressure hot water during heat treatment in heat treatment section 2a be 210°C to 240°C and the pressure of the high-pressure hot water during heat treatment in heat treatment section 2a be 2.0 MPa to 3.6 MPa, from the viewpoints of improving the recovery rate of polymer resin 62 and suppressing deterioration.

[0041] The heat treatment section 2a is preferably provided with a thermometer and a pressure gauge (neither of which is shown) capable of measuring the temperature and pressure, respectively, within the heat treatment section 2a. The heat treatment section 2a may also have a temperature control mechanism for maintaining a constant temperature within the heat treatment section 2a, for example by attaching a jacket to the outside, and it is particularly preferable that the heat treatment section 2a has a jacket as the heating mechanism 23.

[0042] When high-pressure hot water is circulated through the heat treatment section 2a during heat treatment in the heat treatment section 2a, the flow rate of the high-pressure hot water through the heat treatment section 2a can be set appropriately depending on the volume of the heat treatment section 2a, but is preferably 0.01 L / min to 1000 L / min, more preferably 0.1 L / min to 800 L / min, and even more preferably 0.5 L / min to 500 L / min. If the flow rate of the high-pressure hot water is within the above range, polymer resin 62 with reduced degradation can be recovered with high efficiency. The flow rate of the high-pressure hot water through the heat treatment section 2a can be adjusted, for example, by a liquid delivery device (e.g., pump 82). When high-pressure hot water is circulated through the heat treatment section 2a during heat treatment in the heat treatment section 2a, it is preferable that the heat treatment section 2a be a vertical vessel from the viewpoint of reducing energy consumption.

[0043] The separation section 2b may be provided after the heat treatment section 2a (i.e., the separation section 2b may be provided in the heat treatment section 2a). If the heat treatment section 2a is a container-type section, the separation section 2b is preferably provided inside the heat treatment section 2a. By providing the separation section 2b including the first filter member 21 inside the heat treatment section 2a, it becomes easier to maintain the entire composite material 22 in the high-pressure hot water within the heat treatment section 2a during heat treatment. That is, the first filter member 21 also functions as a submersible member that maintains the composite material 22 in the high-pressure hot water. If the entire composite material 22 is maintained in the high-pressure hot water during heat treatment, the composite material 22 and any unmelted material are retained in the high-pressure hot water by the first filter member 21, while the molten polymer resin detaches from the composite material 22 and flows with the water flow generated by the water flow generator 8, passing through the first filter member for easier separation. This allows the polymer resin to be separated and recovered from the composite material 22 more simply and efficiently, and further suppresses deterioration of the recovered polymer resin 62.

[0044] The flow rate of the water flow sent to separation section 2b may be set appropriately depending on the volume of separation section 2b, etc., but is preferably 0.01 L / min to 1000 L / min, more preferably 0.1 L / min to 800 L / min, and even more preferably 0.5 L / min to 500 L / min. If the flow rate of the water flow in separation section 2b is within the above range, polymer resin 62 with reduced degradation can be recovered more efficiently. The flow rate of the water flow in separation section 2b can be adjusted, for example, by a liquid delivery device (e.g., pump 82).

[0045] The shape of the first filter member 21 included in the separation unit 2 b is not particularly limited, and may be, for example, a plate shape, a bucket shape, a cartridge shape, etc. Alternatively, the composite material 22 may be stored inside a basket-shaped container with a lid, and at least a part of the basket-shaped container may serve as the first filter member 21.

[0046] If a high-pressure hot water surface exists inside the heat treatment section 2a during heat treatment and a water flow is generated toward the water surface, it is preferable that the first filter member 21 be fitted inside the heat treatment section 2a so as to separate the heat treatment section 2a into an upper section where the water surface exists and a lower section where high-pressure hot water exists throughout the heat treatment section 2a.

[0047] When the first filter member 21 is provided in the heat treatment section 2a, it is preferable that the first filter member 21 be detachable from the heat treatment section 2a from the viewpoints of ease of maintenance and operation. The first filter member 21 may be detachable, for example, through the opening A of the heat treatment section 2a, or may be detachable through the opening B by attaching an opening B separate from the opening A to the heat treatment section 2a and a cover B that can openably close the opening B. The detachable first filter member 21 makes it possible to easily change the configuration of the first filter member 21 (such as the size of the through holes) and also improves the ease of cleaning the polymer resin recovery apparatus 1, 11, 12, 13.

[0048] The first filter member 21 has a plurality of through holes (A). The size of each through hole (A) in the first filter member 21 is such that the composite material 22 does not pass through but high-pressure hot water and molten polymer resin pass through. Specifically, the opening area of ​​each through hole (A) in the first filter member 21 is 0.001 mm 2 ~200cm 2 is preferable, and 0.05 mm 2 ~200cm 2 More preferably, 0.1 mm 2 ~100cm 2 is more preferable, and 0.3 mm 2 ~50cm 2 is even more preferable. The opening area per through hole (A) of the first filter member 21 is preferably 0.01% to 25% of the area of ​​the composite material 22 to be treated, more preferably 0.05% to 25%, even more preferably 0.1% to 20%, even more preferably 0.1% to 15%, even more preferably 0.2% to 10%, or may be 0.01% to 10% (preferably 0.05% to 10%, more preferably 0.1% to 10%, even more preferably 0.2% to 10%). The mesh size of the first filter member 21 is preferably 0.01 mm to 100 mm, more preferably 0.05 mm to 50 mm, even more preferably 0.08 mm to 25 mm, and even more preferably 0.1 mm to 13 mm. For example, when the area of ​​the composite material 22 is 1600 mm 2 In this case, the size of each of the through holes (A) in the first filter member 21 is preferably 0.4 to 13 mm. When a plurality of composite materials 22 are processed collectively, the area of ​​the composite materials 22 is defined as the average value of the areas of the composite materials 22 used. Of the plurality of through holes (A) in the first filter member 21, the proportion by number of through holes (A) having an opening area within the above range is preferably 60% to 100%, more preferably 80% to 100%, and even more preferably 90% to 100%.

[0049] The total opening area, which is the sum of the opening areas of the multiple through holes (A) in the first filter member 21, is preferably 30% to 95%, more preferably 40% to 93%, and even more preferably 50% to 90% of the area of ​​the filtering surface including the through hole (A) portion of the first filter member 21.

[0050] The size of the first filter member 21 is not particularly limited and may be set appropriately based on the opening area of ​​the separation section 2b. For example, when the separation section 2b is provided inside the heat treatment section 2a, the size of the first filter member 21 need only be such that, when the first filter member 21 is installed in the heat treatment section 2a, the composite material 22 does not pass through the gap between the inner wall of the heat treatment section 2a and the first filter member 21. More specifically, the area of ​​the filtering surface of the first filter member 21, including the through-hole (A) portion, is preferably 80% to 100%, more preferably 90% to 100%, and even more preferably 97% to 100%, of the cross-sectional area of ​​the heat treatment section 2a at the location where the first filter member 21 is installed.

[0051] There are no particular limitations on the thickness of the first filter member 21. For example, the lower limit of the thickness of the first filter member 21 may be set to a thickness that does not cause deformation due to the flow of high-pressure hot water, and the upper limit of the thickness of the first filter member 21 may be set to a thickness that allows the molten polymer resin to easily pass through.

[0052] As the material for the first filter member 21, metals such as silicon, aluminum, nickel, tungsten, copper, titanium, and stainless steel are preferred from the viewpoints of heat resistance, pressure resistance, durability, etc., with aluminum and stainless steel being more preferred. Furthermore, the metal material may be plated with a zinc-based, chromium-based, or nickel-based material. From the viewpoints of reducing adhesion to the polymer resin and improving separation efficiency, the first filter member may have a surface coated with a fluororesin such as Teflon (registered trademark). As the metal material for the first filter member, aluminum is particularly preferred from the viewpoints of heat resistance, pressure resistance, durability, low adhesion to the polymer resin, and high-efficiency separation.

[0053] Examples of the first filter member 21 include metal filters such as metal mesh, punched metal plate, and sintered metal particles or flakes.

[0054] The separation section 2b may be provided with a plurality of filter members, and for example, it is preferable to provide a plurality of filter members with different opening areas and arrange them so that the polymer resin passes through multiple stages. By passing through a filter member with a large opening area and then a filter member with a small opening area, clogging is less likely to occur and the polymer resin can be recovered more efficiently.

[0055] Although not shown, the polymer resin recovery devices 1, 11, 12, and 13 may have a backwashing mechanism for backwashing the first filter element 21. The backwashing mechanism may be configured to apply a flow of water substantially opposite to the flow direction of the water flow generated by the water flow generating unit 8 to the first filter element 21, and may be, for example, composed of a pump and piping for supplying backwash water, or may be composed of a pressurized gas storage tank and piping for applying pressure using gas or the like. The backwashing mechanism can prevent a decrease in the separation efficiency of the first filter element 21 and prevent clogging of the first filter element 21 during polymer resin recovery.

[0056] The water flow generating unit 8 may be configured to generate a water flow. For example, a conventional stirring device such as an impeller, magnetic stirrer, or mechanical stirrer may be used to generate a water flow by stirring. Alternatively, a water flow may be generated by introducing a fluid (water, hot water, etc.) into the separation unit 2b via a pump and piping. Examples of the stirring blade include propeller blades, paddle blades, turbine blades, anchor blades, and ribbon blades. Since they can generate a water flow in a substantially unidirectional manner, stirring blades with inclined paddle shapes are preferred. Figure 3 shows an embodiment in which the water flow generating unit 8 is an stirring blade 81. Figures 1 and 2 show an embodiment in which the water flow generating unit 8 is a pump 82. Figure 4 shows an embodiment in which the water flow generating unit 8 is an stirring blade 81 and a pump 82. The water flow generating unit 8 is preferably an stirring blade or a pump, and more preferably, the water flow generating unit 8 is equipped with at least a stirring blade. When the separation unit 2b is disposed inside the heat treatment unit 2a and has an agitator blade 81 as the water flow generating unit 8, it is preferable that the agitator blade 81, which is the water flow generating unit 8, be provided inside the heat treatment unit 2a, as exemplified in Figures 3 and 4. In Figures 3 and 4, the agitator blade 81 has an agitator shaft inserted from the bottom of the container of the heat treatment unit 2a, but the agitator shaft may also be inserted from the lid of the container (from above). In this case, the agitator blade may be located above the first filter element 21, or the agitator shaft may pass through the first filter element 21 and the agitator blade may be located below the first filter element 21.

[0057] Generally, the larger the volume and diameter of the heat treatment section 2a, the larger the stirring blade used, but it is preferable that the ratio of the maximum diameter of the stirring blade's rotation range to the diameter of the vessel be 0.1 to 0.95. This ratio is more preferably 0.2 or more, even more preferably 0.3 or more, and may be 0.4 or more, or even 0.5 or more. The ratio may also be 0.9 or less, or 0.85 or less.

[0058] When the separation section 2b is disposed within the thermal treatment section 2a and includes a pump 82 as the water flow generator 8, the piping connecting the pump 82 to the thermal treatment section 2a (separation section 2b) may be the hot water supply section 3, as illustrated in FIGS. 1 to 3 , or the piping may be provided separately from the hot water supply section 3. When the separation section 2b is disposed within the thermal treatment section 2a and includes a pump 82 as the water flow generator 8, the fluid introduced into the thermal treatment section 2a (separation section 2b) may be hot water extracted from the thermal treatment section 2a (separation section 2b). In other words, as illustrated in FIGS. 1 and 2 , a configuration in which hot water is circulated may be used. The extraction of hot water may be performed from a discharge section that extracts only hot water, or via a discharge section 4 that extracts both the molten polymer resin and hot water. When the hot water extracted via the discharge section 4 is introduced into the thermal treatment section 2a (separation section 2b), it is preferable to have a configuration (e.g., a recovery section 6) downstream of the discharge section 4 and upstream of the pump 82 that removes the polymer resin.

[0059] The direction of the water flow generated by the water flow generator 8 can be any direction, such as upward, downward, or sideways. The water flow generator 8 can be installed to generate a water flow in any direction, taking into account the shape of the heat treatment unit 2a where the heat treatment is performed and the shape of the separation unit 2b. The water flow generator 8 may also be configured to change the direction of the water flow. For example, if the water flow generator 8 is a pump 82, an angle-adjustable nozzle may be provided on the heat treatment unit 2a (separation unit 2b) side of the piping connecting the pump 82 to the heat treatment unit 2a (separation unit 2b). From the standpoints of water flow stability and separation efficiency of the polymer resin 62, the water flow generator 8 is preferably configured to generate an upward water flow. Note that the upward direction does not have to be completely vertical (anti-gravity direction) and may be diagonally upward. In the case of an obliquely upward direction, the inclination with respect to the horizontal direction (the direction perpendicular to the direction of gravity) is preferably 20 degrees or more, more preferably 30 degrees or more, even more preferably 40 degrees or more, and particularly preferably 50 degrees or more, 60 degrees or more, 70 degrees or more, and 80 degrees or more. In the case of a vortex (swirl flow) generated by stirring or the like, it is preferable that the entire vortex (swirl flow) faces upward.

[0060] The speed of the water flow (water flow velocity) generated by the water flow generating unit 8 is preferably 0.001 m / s to 1 m / s, more preferably 0.002 m / s to 1 m / s, and even more preferably 0.01 m / s to 0.5 m / s. By keeping the water flow velocity within this range, the polymer resin 62 can be recovered more efficiently.

[0061] When the water flow generating unit 8 is an agitator blade, the rotation speed of the agitator blade is preferably 1 to 3,000 rpm, more preferably 10 to 3,000 rpm, and even more preferably 20 to 2,000 rpm, depending on the volume (size of the container) of the heat treatment unit 2a, the diameter of the container, the ratio of the diameter to the length of the container, the shape and size of the agitator blade. To achieve a stable and uniform water flow, the larger the agitator blade, the larger the container, the shorter the length relative to the diameter of the container, and the larger the agitator blade relative to the diameter of the container, the lower the rotation speed is. For example, when the volume of the container of the heat treatment unit 2a is 100 L or more, depending on the shape of the agitator blade, the rotation speed of the agitator blade is preferably 1 to 500 rpm, more preferably 5 to 300 rpm, even more preferably 10 to 200 rpm, and most preferably 20 to 100 rpm. By keeping the rotation speed of the agitator blade within the above range, the polymer resin 62 can be recovered more efficiently.

[0062] The heating mechanism 23 that may be provided in the heat treatment section 2a may be configured to heat the heat treatment section 2a from the outside or from the inside. When the heat treatment section 2a is configured to heat the heat treatment section 2a from the outside, examples of the heating mechanism 23 include a jacket, an electric heating wire (heater), an induction heating device, etc. When the heat treatment section 2a is configured to heat the heat treatment section 2a from the inside, examples of the heating mechanism 23 include an immersion heater, a steam introduction device, etc. The heating mechanism 23 is preferably configured to heat the heat treatment section 2a from the outside, and a jacket or heater is more preferred from the viewpoint of device handleability. The jacket is configured to allow a heat medium to circulate inside, and can also function as a cooling mechanism by circulating a refrigerant. The heating mechanism 23 may be installed to heat the entire heat treatment section 2a or a portion of the heat treatment section 2a. From the viewpoint of heating efficiency, it is preferable to install it to heat at least the bottom of the heat treatment section 2a.

[0063] The polymer resin recovery apparatus 1, 11, 12, and 13 of the present invention can be used to increase the temperature and / or pressure during heat treatment to the desired treatment temperature and / or treatment pressure in a short time. For example, the polymer resin recovery apparatus 1, 11, 12, and 13 of the present invention can increase the temperature from 80°C to the treatment temperature within 60 minutes, more preferably within 30 minutes, even more preferably within 20 minutes, even more preferably within 10 minutes, and particularly preferably within 5 minutes. If the time required to increase the temperature from 80°C to the treatment temperature is within 60 minutes, a polymer resin 62 with further suppressed deterioration can be recovered. Furthermore, the polymer resin recovery apparatus 1, 11, 12, and 13 of the present invention can increase the pressure from 0.05 MPa to the treatment pressure within 60 minutes, more preferably within 30 minutes, even more preferably within 20 minutes, even more preferably within 10 minutes, and particularly preferably within 5 minutes. If the time required to increase the pressure from 0.05 MPa to the treatment pressure is within 60 minutes, the polymer resin 62 can be recovered with further suppressed deterioration.

[0064] By using the polymer resin recovery devices 1, 11, 12, and 13 of the present invention, the polymer resin 62 can be efficiently recovered even with a relatively short heat treatment time. The heat treatment time can be set appropriately depending on the treatment temperature and treatment pressure, but is preferably 30 seconds to 240 minutes, more preferably 45 seconds or more, even more preferably 1 minute or more, more preferably 180 minutes or less, even more preferably 120 minutes or less, and even more preferably 60 minutes or less. That is, the heat treatment time is preferably 45 seconds to 180 minutes, even more preferably 1 minute to 120 minutes, and even more preferably 1 minute to 60 minutes. If the treatment time is within the above range, the polymer resin 62 can be easily separated from the unmelted material (such as silicone resin) while suppressing degradation, such as decomposition, of the polymer resin 62.

[0065] Since the polymer resin melted by the heat treatment solidifies upon cooling, cooling after the heat treatment allows the polymer resin to be separated from the composite material 22 and unmelted materials (such as silicone resin) as a solid. A solid state is preferable because it is easy to handle. The polymer resin recovery apparatus of the present invention may have a cooling mechanism 5 capable of cooling the heat treatment section 2a and / or the polymer resin after the heat treatment. If the polymer resin recovery apparatus does not have a cooling mechanism 5, the polymer resin melted by the heat treatment solidifies by natural cooling. From the viewpoint of further suppressing deterioration of the resulting polymer resin 62, the polymer resin recovery apparatus preferably has a cooling mechanism 5. A known cooler, such as a water-cooled or air-cooled type, can be used as the cooling mechanism 5. The cooling mechanism 5 may be provided in the heat treatment section 2a or the separation section 2b, or may be provided downstream of the heat treatment section 2a or the separation section 2b. From the viewpoint of recovering a polymer resin 62 with further suppressed deterioration, it is preferable to provide the cooling mechanism 5 downstream of the heat treatment section 2a. When the polymer resin recovery device has a cooling mechanism 5 and a recovery section 6 , the cooling mechanism 5 is preferably provided in the recovery section 6 or upstream of the recovery section 6 .

[0066] Specifically, the cooling mechanism 5, 51, which cools the high-pressure hot water and molten polymer resin discharged from the discharge section 4 illustrated in Figures 1, 2, and 4, cools the treatment liquid (water containing the polymer resin) to a temperature below the melting point of the polymer resin. When the composite material 22 contains polyamide polyester as the polymer resin, the cooling mechanism 5, 51 preferably cools the treatment liquid to a temperature below the melting point of the polymer resin in water, more preferably below 150°C, even more preferably below 130°C, and may be below 120°C, below 110°C, or even below 100°C. Furthermore, considering the removal of the separated polymer resin, a temperature of 80°C or less is even more preferable, and a temperature of 60°C or less is particularly preferable. The temperature of the treatment liquid is preferably 20°C or higher, more preferably 30°C or higher. That is, the temperature of the treatment liquid is preferably 20°C or higher and lower than its melting point in water, more preferably 30°C or higher and lower than 150°C, and even more preferably a combination of 30°C or higher and lower than 130°C, 120°C, 110°C, 100°C, 80°C or lower, or 60°C or lower. The cooling mechanisms 5, 51 may be any cooling mechanism capable of maintaining the treatment liquid within the above temperature range, such as a liquid circulation cooling mechanism that circulates a cooling liquid (e.g., cold water). In the polymer resin recovery devices 1, 11, 13, the cooling mechanisms 5, 51 cool the treatment liquid below the temperature at which the polymer resin melts, solidifying the polymer resin and allowing it to be recovered in the recovery section 6. Furthermore, by cooling the high-pressure hot water and molten polymer resin discharged from the discharge section 4 using the cooling mechanisms 5, 51, the progression of degradation of the polymer resin can be further suppressed.

[0067] Furthermore, when the cooled water is circulated and reused, a low cooling temperature increases the energy required for reheating. In such cases, the temperature of the treatment liquid during treatment operation is preferably 100°C or higher, more preferably 110°C or higher, and even more preferably 120°C or higher. When the treatment operation is interrupted and the polymer resin is removed, it is also preferable to set the temperature to less than 100°C, 80°C or lower, or 60°C or lower. That is, when the cooled water is circulated and reused, the cooling temperature during treatment operation is preferably 100°C or higher and lower than the melting point in water, more preferably 110°C or higher and lower than the melting point in water, even more preferably 120°C or higher and lower than the melting point in water, more preferably 100°C or higher and lower than 150°C, even more preferably 110°C or higher and lower than 150°C, and even more preferably 110°C or higher and lower than 130°C. The cooling temperature when the polymer resin is removed after the treatment operation is interrupted is preferably 20°C or higher and lower than 100°C, more preferably 30°C or higher and lower than 80°C, and even more preferably 30°C or higher and lower than 60°C.

[0068] By using the polymer resin recovery devices 1, 11, 12, and 13 of the present invention, for example, the temperature can be lowered from the treatment temperature to 80° C. within 60 minutes, preferably within 30 minutes, and more preferably within 20 minutes. If the time required to lower the temperature from the treatment temperature to 80° C. is within 60 minutes, it is possible to recover a polymer resin with further suppressed deterioration.

[0069] The polymer resin recovery apparatus of the present invention may include a recovery section 6 for recovering solidified polymer resin. Specifically, the recovery section 6 recovers the solidified polymer resin after melting and separating it from the composite material 22 by heat treatment. If the polymer resin recovery apparatus does not include the recovery section 6, the polymer resin 62 may be recovered from the heat treatment section 2a or the discharge section 4 using a scoop or the like, or by filtering the treatment liquid using a known filtration device provided separately from the polymer resin recovery apparatus. The polymer resin recovery apparatus of the present invention includes a separation section 2b equipped with a first filter member, thereby easily recovering the polymer resin 62. From the viewpoint of improving the recovery efficiency of the polymer resin 62, the polymer resin recovery apparatus preferably includes the recovery section 6. Recovery in the recovery section 6 may be performed by filtration using a filter member (second filter member) or the like, or may be performed by scraping using a scraping device equipped with a scraping means such as a rotatable scraping blade. From the viewpoint of more efficient recovery of the polymer resin 62, recovery in the recovery section 6 is preferably performed by filtration using a second filter member.

[0070] The polymer resin recovery apparatus of the present invention may be configured such that multiple recovery sections 6 are provided in parallel (when the cooling mechanism 5 and recovery section 6 are integrated, multiple cooling mechanisms 5 and recovery sections 6 are provided in parallel), and the flow path from the heat treatment section 2a to the recovery section 6 is switched to allow continuous treatment operation using other recovery sections 6 while removing the polymer resin recovered from at least one recovery section 6. In this case, the cooling mechanisms 5, 51 preferably adjust the temperature of the treatment liquid in the operating recovery section 6 to the cooling temperature during the treatment operation, and the recovery section 6 from which the polymer resin is removed preferably adjusts the temperature to the cooling temperature at the time of removal. The polymer resin recovery apparatus of the present invention may also be configured such that multiple heat treatment sections 2a are provided in parallel, and the flow path from the heat treatment section 2a to the recovery section 6 is switched to allow continuous treatment operation using other heat treatment sections 2a while replacing the composite material 22 being heat-treated in at least one heat treatment section 2a. When multiple recovery sections 6 and / or heat treatment sections 2a are provided in parallel, it is preferable that the number of recovery sections 6 and heat treatment sections 2a be either two, three, or four, independently of one another.

[0071] When the recovery unit 6 is a container type equipped with a second filter member provided downstream of the heat treatment unit 2a, the internal volume of the recovery unit 6 is, for example, preferably 0.5 L to 1500 L, more preferably 1 L or more, even more preferably 2 L or more, even more preferably 5 L or more, more preferably 1200 L or less, even more preferably 1000 L or less, and even more preferably 800 L or less. That is, the internal volume of the recovery unit 6 is more preferably 1 L to 1200 L, more preferably 2 L to 1000 L, and even more preferably 5 L to 800 L. By having the internal volume of the recovery unit 6 within the above range, the polymer resin 62 can be recovered more efficiently.

[0072] The second filter member 61 is preferably detachable from the recovery unit 6. The second filter member 61 may be detachable through an opening C by attaching an opening C to the recovery unit 6 and a cover C that can openably and closably close the opening C. Because the second filter member 61 is detachable, the recovered polymer resin 62 can be easily removed. Furthermore, because the second filter member 61 is detachable, the configuration of the second filter member 61 (such as the size of the through holes) can be easily changed, which also improves the ease of cleaning the polymer resin recovery device.

[0073] The second filter member 61 has a plurality of through holes (B). The size of each through hole (B) in the second filter member 61 is large enough to filter the polymer resin 62 solidified by cooling and separate it from the water. Specifically, the opening area of ​​each through hole (B) in the second filter member 61 is 0.001 mm 2 ~1cm 2 is preferable, and 0.005 mm 2 ~0.8cm 2 More preferably, 0.01 mm 2 ~0.5cm 2 Of the plurality of through holes (B) in the second filter member 61, the proportion of the number of through holes (B) having an opening area within the above range is preferably 60% to 100%, more preferably 80% to 100%, and even more preferably 90% to 100%.

[0074] A known filter having the through-holes (B) of the above-described embodiment can be used as the second filter member 61. The second filter member 61 may be, for example, a woven or nonwoven fabric made of fibers of metal, resin, glass, or the like, or may be a plate- or bucket-shaped member made of metal, resin, or the like with a plurality of fine holes formed therethrough.

[0075] The polymer resin recovery device of the present invention may be configured so that the liquid after removing the polymer resin 62 in the recovery section 6 or the like is directly discharged from a drain (not shown), or may be configured so that residue removal filters 111, 112 are provided as needed to remove fine residue from the liquid before discharging the liquid from the drain. As the residue removal filters 111, 112, known filters having pores of a size that allows water to pass through but does not allow the residue that is desired to be removed to pass through can be used.

[0076] A water storage tank 9 may be provided downstream of the separation section 2b or the recovery section 6 (preferably downstream of the residue removal filters 111, 112) to temporarily store the liquid after removing the polymer resin 62. Providing the water storage tank 9 allows for further post-treatment (e.g., pH adjustment) of the liquid. Furthermore, providing a high-pressure hot water preparation mechanism 7b downstream of the water storage tank 9 allows the water stored in the water storage tank 9 to be used as raw water for the high-pressure hot water. When the post-treatment is performed in the water storage tank 9, a second water storage tank (not shown) for storing the post-treatment water may be further provided. When the liquid after removing the polymer resin 62 is reused as raw water for the high-pressure hot water, the provision of the second water storage tank allows for post-treatment of the liquid in the water storage tank 9 without stopping the supply of high-pressure hot water. The internal volumes of the water storage tank 9 and the second water storage tank are not particularly limited and may be appropriately designed depending on the amount of water circulating through the polymer resin recovery apparatus.

[0077] The pressure adjustment mechanism 71 constituting the high-pressure hot water preparation mechanism 7b can be a valve or the like, preferably a pressure adjustment valve equipped with a pressure control device. The heating mechanism 72 constituting the high-pressure hot water preparation mechanism 7b can be, for example, a light heating (infrared) type, an IH heater type, an alumina heater type, an oil heater type, or the like.

[0078] If the polymer resin recovery device does not have the high-pressure hot water preparation mechanism 7b, a known high-pressure hot water production device may be connected to the hot water supply unit 3 to supply high-pressure hot water to the heat treatment unit 2a.

[0079] In addition to the above configuration, the polymer resin recovery devices 1, 11, 12, and 13 may be provided with devices such as a liquid delivery device (such as a liquid delivery pump), a thermometer, and a pressure gauge at any desired location.

[0080] The composite material 22 processed by the polymer resin recovery apparatuses 1, 11, 12, and 13 of the present invention contains a polymer resin. The composite material 22 can be various molded products (preferably, various used molded products to be recycled) or scraps generated during the manufacture of molded products. Examples of the composite material 22 include textile products such as airbag fabric, film products, and bottle products. Textile products are preferred, and airbag fabric is more preferred. Specifically, airbag fabric is a base fabric formed from a polymer resin such as a polyamide resin or a polyester resin, to which a silicone resin is applied. In airbag fabric, the silicone resin need only be applied to at least one side of the base fabric. When the composite material 22 is airbag fabric, the airbag fabric may be scraps generated during the manufacture of airbags or waste from used airbags. When used airbags are used, the fabric is preferably fabric pieces obtained by cutting or shredding.

[0081] The polymer resin constituting the airbag fabric is preferably a polyamide-based resin or a polyester-based resin. The base fabric, which is a polyamide or polyester fabric, is preferably a woven fabric composed of multifilaments of polyamide or polyester fibers. Examples of the woven fabric include plain weave, twill weave, satin weave, and variations thereof. From the viewpoint of recovering the polymer resin 62 with high recyclability, the number of filaments in the multifilament yarn constituting the woven fabric (base fabric) is preferably, for example, 30 to 200, and more preferably 40 to 180. The number of filaments can be determined by counting from a cross-sectional photograph of the multifilament yarn. From the viewpoint of recovering the polymer resin 62 with high recyclability, the total fineness of the multifilament yarn constituting the woven fabric (base fabric) is preferably, for example, 200 dtex to 1000 dtex, and more preferably 250 dtex to 800 dtex. The total fineness of the multifilament yarn can be measured in accordance with JIS L1013 (2010) 8.3.1. From the viewpoint of recovering the polymer resin 62 with higher recyclability, the tensile strength of the multifilament yarn constituting the woven fabric (base fabric) is preferably, for example, 6.0 cN / dtex to 10 cN / dtex, and more preferably 6.5 cN / dtex to 9.5 cN / dtex. The tensile strength of the multifilament yarn can be measured in accordance with JIS L1013 (2010) 8.5.1. From the viewpoint of recovering the polymer resin 62 with higher recyclability, the weave density of the woven fabric (base fabric) is preferably, for example, 35 threads / 2.54 cm to 80 threads / 2.54 cm in both the warp and weft directions, and more preferably 40 threads / 2.54 cm to 75 threads / 2.54 cm. The weave density can be measured in accordance with JIS L1096 (2010) 8.6.1. From the viewpoint of recovering the polymer resin 62 with higher recyclability, the cover factor (CF) of the woven fabric (base fabric) is preferably, for example, 1,500 to 2,500, and more preferably 1,700 to 2,300. The cover factor is an index of the coverage rate of the woven fabric, and can be calculated by the following formula: CF = (total fineness of warp yarns) 0.5 × Warp density + (total weft fineness) 0.5 ×Weft density

[0082] The polymer resin recovery device of the present invention utilizes the fact that polymer resins in a hydrated state have a lower melting point and can be molten even at relatively low temperatures, and thus performs heat treatment in a hydrated state to release the polymer resin from the composite material 22. For this reason, the polymer resin contained in the composite material 22 is preferably a polymer resin that melts in high-pressure hot water (preferably water at 1.0 MPa to 4.0 MPa and 160°C to 250°C), and examples of such polymer resins include polyamide-based resins and polyester-based resins. The inventors have confirmed that polyamide-based resins and polyester-based resins can be sufficiently melted by treatment with high-pressure hot water (water at 1.0 MPa to 4.0 MPa and 160°C to 250°C (preferably 180°C to 250°C)) because their melting points are lower than their melting points in air. Specifically, the melting point of nylon 66, a polyamide resin, was measured using a differential scanning calorimeter (DSC; "DSC214Polyma" manufactured by Netsch Japan Co., Ltd.) to measure the heat flow and confirm the melting point in air and water. The measured melting point in air was 257°C, while the measured melting point in water was 177°C. DSC measurements were performed by placing 10 mg of nylon 66 (for measurements in air) or 10 mg of nylon 66 and 19 mg of water (for measurements in water) in a pressure-resistant DSC pan, over a temperature range of 30°C to 300°C, at a heating rate of 10°C / min, and the temperature at the maximum endothermic peak was taken as the melting temperature (melting point). DSC measurement data for nylon 66 in air and water are shown in Figure 5. As shown in Figure 5, the melting point of nylon 66 was approximately 80°C lower in water than in air. Similarly, when the melting point of polyethylene terephthalate was measured using DSC, it was found that the melting point in water was about 30° C. lower than that in air.

[0083] Polyamide resins are polymers having amide bonds in their main chains. Examples of polyamide resins include polycaproamide (nylon 6), polyhexamethylene adipamide (nylon 66), polytetramethylene adipamide (nylon 46), polyhexamethylene sebacamide (nylon 610), polyhexamethylene dodecamide (nylon 612), polylauryllactam (nylon 12), and polyundecaneamide (nylon 11), as well as copolymers and mixtures thereof. For airbag fabrics having a base fabric formed from a polyamide resin, polycaproamide resin obtained by polycondensation of ε-caprolactam, commonly known as nylon 6, and nylon 66 are typically preferred in terms of heat resistance and cost, with nylon 66 being particularly preferred. Therefore, nylon 6 and nylon 66 are preferred polyamide resins contained in the composite material 22 in terms of versatility, with nylon 66 being more preferred.

[0084] Polyester-based resins are formed by reacting a carboxylic acid component with a hydroxyl group component. Examples of carboxylic acid components include terephthalic acid, isophthalic acid, adipic acid, sebacic acid, and naphthalenedicarboxylic acid. Examples of hydroxyl group components include ethylene glycol, 1,4-butanediol, diethylene glycol, neopentyl glycol, and cyclohexanedimethanol. Examples of polyester-based resins include polyethylene terephthalate, polytrimethylene terephthalate, polybutylene terephthalate, and copolymer polyesters obtained by copolymerizing these polymers with a third component. For airbag fabrics having a base fabric formed from a polyester-based resin, polyethylene terephthalate is typically preferred because it combines cost with physical properties such as strength. For this reason, polyethylene terephthalate is preferred as the polyester-based resin contained in the composite material 22 in terms of versatility.

[0085] The polymer resin content in the composite material 22 is preferably 40% by mass to 99.5% by mass, more preferably 50% by mass or more, even more preferably 60% by mass or more, and more preferably 99% by mass or less, and even more preferably 97% by mass or less. That is, the polymer resin content in the composite material 22 is more preferably 50% by mass to 99% by mass, and even more preferably 60% by mass to 97% by mass.

[0086] The composite material 22 contains components other than the polymer resin. The other components preferably do not melt or decompose in high-pressure hot water (preferably, water at 1.0 MPa to 4.0 MPa and 160°C to 250°C (preferably, 180°C to 250°C)), or are water-soluble. Components that do not melt or decompose in high-pressure hot water are restricted in movement by the first filter member 21 and are retained within the heat treatment unit 2a, allowing high-purity polymer resin 62 to be recovered. Water-soluble components are not captured by the second filter member 61 of the recovery unit 6, allowing high-purity polymer resin 62 to be more easily recovered.

[0087] Examples of other components include antioxidants, heat stabilizers, smoothing agents, antistatic agents, thickeners, flame retardants, weather resistance agents, coloring inhibitors, colorants, reinforcing agents, and surface treatment agents. Specifically, a preferred other component is silicone resin. The present inventors have confirmed that silicone resin does not melt or decompose when exposed to high-pressure hot water (water at 1.0 MPa to 4.0 MPa and 160°C to 250°C (preferably 180°C to 250°C)).

[0088] The silicone resin is not particularly limited, but specific examples include addition polymerization type silicone rubber, etc. Examples include dimethyl silicone rubber, methyl vinyl silicone rubber, methyl phenyl silicone rubber, trimethyl silicone rubber, fluorosilicone rubber, methyl silicone resin, methyl phenyl silicone resin, methyl vinyl silicone resin, epoxy-modified silicone resin, acrylic-modified silicone resin, polyester-modified silicone resin, etc. Among these, addition polymerization type methyl vinyl silicone rubber is preferred.

[0089] The composite material 22 may be a laminate of a polymer resin and other components, i.e., a laminate including a layer formed from a polymer resin (e.g., a polyamide cloth or a polyester cloth) and a layer formed from other components (e.g., a silicone resin layer).

[0090] When the composite material 22 is an airbag fabric, the airbag fabric preferably comprises a silicone resin-containing coating resin applied to at least one side of a base fabric to form a silicone resin layer. The viscosity of the coating resin is preferably 5,000 mPa·sec to 40,000 mPa·sec, and more preferably 7,000 mPa·sec to 38,000 mPa·sec. Within the above viscosity range, the coating resin may be either solvent-based or solventless, with solventless being preferred. In this specification, the viscosity of the coating resin refers to the viscosity of a coating resin composition containing additives other than the resin, i.e., the viscosity of the resin actually applied to the base fabric. The coating resin may contain additives other than the silicone resin and solvent. Examples of such additives include reactive curing agents such as platinum catalysts (specifically, platinum black, chloroplatinic acid, alcohol-modified chloroplatinic acid, complexes of chloroplatinic acid with olefins, aldehydes, vinylsiloxanes, or acetylene alcohols); adhesion aids such as amino silane coupling agents, epoxy-modified silane coupling agents, vinyl silane coupling agents, chlorine-based silane coupling agents, and mercapto silane coupling agents; reinforcing inorganic fillers such as fumed silica and dry silica; non-reinforcing inorganic fillers such as crosslinkable silicones (silicone resins) with modified terminal groups, calcium carbonate, calcium silicate, and titanium dioxide; antioxidants; antistatic agents; flame retardants; weathering agents; coloring inhibitors; and colorants. When a platinum catalyst is contained as a reactive curing agent, the content is preferably 100 ppm to 2000 ppm, and more preferably 150 ppm to 1800 ppm, of platinum metal per 100 parts by mass of silicone resin. When a silane coupling agent is contained as an adhesion aid, the content thereof is preferably 0.01 to 3 parts by mass, more preferably 0.02 to 2 parts by mass, per 100 parts by mass of the silicone resin. When an inorganic filler is contained, the content thereof is preferably 0.1 to 200 parts by mass, more preferably 0.1 to 100 parts by mass, per 100 parts by mass of the silicone resin. The coating resin (i.e., silicone resin) on the base fabric may be applied using a conventional, known application method.Examples of coating methods include knife coating, roll coating, reverse coating, gravure coating, gravure reverse coating, and kiss coating, and it is preferable that the silicone resin is applied by knife coating.

[0091] The amount of silicone resin applied to the airbag fabric, which is the composite material 22, is set to 5 g / m from the viewpoint of ease of separation of the polymer resin from the silicone resin. 2 ~150g / m 2 It is preferable that the density is 7 g / m 2 More preferably, 10 g / m or more 2 More preferably, 120 g / m 2 More preferably, 100 g / m or less 2 More preferably, 70 g / m or less 2 More preferably, the amount of silicone resin applied to the composite material 22 is 7 g / m 2 ~120g / m 2 More preferably, 10 g / m 2 ~100g / m 2 More preferably, 10 g / m 2 ~70g / m 2 is even more preferred.

[0092] When the composite material 22 is an airbag fabric, the airbag fabric may contain a mixture of uncoated airbag fabric and / or non-silicone-coated airbag fabric, but preferably silicone-coated airbag fabric, in which a silicone resin layer is formed on at least one side of a base fabric, accounts for 50% or more by mass of the entire airbag fabric, more preferably 60% or more by mass, even more preferably 70% or more by mass, and particularly preferably 80% or more by mass.

[0093] From the viewpoint of ease of separation of the polymer resin, the weight ratio of the polymer resin in the composite material 22 is preferably 50% by weight to 99% by weight, more preferably 55% by weight or more, even more preferably 60% by weight or more, even more preferably 70% by weight or more, and more preferably 97% by weight or less, even more preferably 95% by weight or less, and even more preferably 93% by weight or less. That is, the weight ratio of the polymer resin in the composite material 22 is preferably 55% by weight to 97% by weight, even more preferably 60% by weight to 95% by weight, and even more preferably 70% by weight to 93% by weight. Note that when the composite material 22 is an airbag fabric and the proportion of materials other than the polymer resin in the base fabric is small (for example, 5% by weight or less, or even 3% by weight or less), the weight ratio of the polymer resin described above may be interpreted as the weight ratio of the base fabric.

[0094] The content of the other components in the composite material 22 is preferably 0.5% by mass to 60% by mass, more preferably 50% by mass or less, even more preferably 40% by mass or less, and may be 1% by mass or more or 3% by mass or more. That is, the content of the other components in the composite material 22 is more preferably 1% by mass to 50% by mass, even more preferably 3% by mass to 40% by mass.

[0095] The polymer resin 62 recovered by the polymer resin recovery devices 1, 11, 12, and 13 of the present invention is exposed to high pressure and high temperature for a short period of time, and therefore deterioration is suppressed. Furthermore, the polymer resin recovery device 12 of the present invention uses a water flow to separate the polymer resin 62, and the polymer resin recovery devices 1, 11, and 13 of the present invention use a water flow to separate and recover the polymer resin 62, so that they are simple devices that do not require complicated operations.

[0096] The polymer resin 62 recovered using the polymer resin recovery devices 1, 11, 12, and 13 of the present invention may be appropriately subjected to post-treatments such as washing with a cleaning liquid such as water or an organic solvent, drying, etc. After the recovered polymer resin 62 is washed with a cleaning liquid such as water or an organic solvent, or subjected to post-treatments such as drying, it can be melted by heat or using a solvent, and pelletized or sheeted to obtain a recycled polymer resin composition.

[0097] The polymer resin 62 recovered by the polymer resin recovery apparatus 1, 11, 12, and 13 of the present invention preferably has a low silicone content. In recycled polymer resin compositions using the polymer resin 62, the silicone content is preferably 50,000 ppm or less, more preferably 40,000 ppm or less, and even more preferably 30,000 ppm or less. By keeping the silicone content below the upper limit, problems such as thread breakage and film rupture are less likely to occur when the recycled polymer resin composition is processed into fibers, films, molded products, etc., and deterioration of appearance such as strength reduction due to foreign matter, surface roughness, and foreign matter defects are less likely to occur. Furthermore, when the recycled polymer resin composition is processed, filter clogging is less likely to occur when the molten resin is filtered, allowing for continuous and stable production of processed products. On the other hand, when the composite material 22 is an airbag fabric, silicone-based oils may be used in the spinning and weaving process of the base fabric of the airbag fabric, and the silicone-based oils may not be completely removed. Furthermore, while the amount of silicone resin can be reduced by improving the precision of the first filter member, this may result in a slower filtration rate and reduced productivity. Taking these factors into consideration, the lower limit of the silicone content in a recycled polymer resin composition using polymer resin 62 may be 2000 ppm, 4000 ppm, or even 5000 ppm. Recycled polymer resin compositions with a low silicone content can be used in a wide range of applications as material recycled polymer resin compositions. The silicone content can be measured, for example, by the following method. The polymer resin 62 recovered by the polymer resin recovery device is powdered by freeze-pulverization to prepare a measurement sample. Using an X-ray fluorescence spectrometer (XL3t-950S, manufactured by Thermo Fisher Scientific), measurements are performed in the Cu / Zn mode of the mineral mode (FP method) with a measurement field of view of an 8 mm diameter spot. The amount of Si element (mass ppm) in the obtained sample can be evaluated as the silicone content.In this specification, the recovered polymer resin 62 may contain various additives and trace amounts of coating agent derived from the base fabric, and although it is sometimes referred to as a polymer resin composition, it can also be considered the same as a polymer resin. When measured using the above method, even nylon 66 (a polyamide resin), the raw material for airbag base fabrics, may exhibit a silicone content of 3,000 to 3,500 ppm. Furthermore, when pelletized without removing the coating agent, it may exhibit a value of 250,000 to 300,000 ppm. Taking into account additives derived from the base fabric (such as silicone oil), if the silicone content is below the upper limit, it can be considered that most of the coating agent (coating resin containing silicone resin) has been removed.

[0098] The silicone content can be further reduced by reducing the opening area of ​​the first filter member or by passing the polymer resin 62 through an additional filter when pelletizing or sheeting it. The silicone content can also be reduced by increasing the amount of water (high-pressure hot water) used relative to the composite material 22 during heat treatment. The lower limit of the amount of water used relative to the composite material 22 is preferably 1.1 times by mass, more preferably 1.5 times, even more preferably 2 times, even more preferably 5 times, even more preferably 10 times, and even more preferably 30 times. By using an amount of water relative to the composite material 22 that is equal to or greater than the lower limit, the separation efficiency of the polymer resin is improved. The upper limit of the amount of water used relative to the composite material 22 is preferably 10,000 times by mass, more preferably 5,000 times, and even more preferably 1,000 times, but is not particularly limited thereto. In a flow-type apparatus equipped with a pump 82 as a water flow generator 8, as exemplified in FIGS. 1 and 2 , the amount of water used relative to the composite material 22 can be even greater. That is, the amount of water used relative to the composite material 22 is, for example, preferably 1.1 to 10,000 times by mass, more preferably 1.5 to 10,000 times, even more preferably 2 to 10,000 times, even more preferably 5 to 10,000 times, even more preferably 10 to 5,000 times, and even more preferably 30 to 1,000 times.

[0099] The polymer resin 62 recovered by the polymer resin recovery devices 1, 11, 12, and 13 preferably contains substantially no components other than the polymer resin 62. "Substantially no" means that the content of components other than the polymer resin in the polymer resin 62 is 3% by mass or less, preferably 1% by mass or less, more preferably 0.5% by mass or less, and even more preferably 0.1% by mass or less. There is no particular lower limit, and the content is preferably 0% by mass or more, and may be 0.01% by mass or more. That is, the content of components other than the polymer resin in the polymer resin 62 is preferably 0% by mass to 3% by mass, more preferably 0% by mass to 1% by mass, more preferably 0% by mass to 0.5% by mass, and even more preferably 0.01% by mass to 0.1% by mass or less. A polymer resin 62 that does not substantially contain components other than the polymer resin 62 is highly recyclable. The content of components other than the polymer resin 62 contained in the polymer resin 62 can be calculated based on values ​​obtained using, for example, a Fourier transform infrared spectrophotometer (FT-IR) or the like.

[0100] Furthermore, the polymer resin 62 recovered by the polymer resin recovery devices 1, 11, 12, and 13 preferably has low alkali metal and alkaline earth metal contents. The alkali metal content is the sum of the amounts of potassium, sodium, and lithium, and the alkaline earth metal content is the sum of the amounts of calcium and magnesium. The total amount of alkali metals and alkaline earth metals is preferably 1000 ppm or less, more preferably 700 ppm or less, even more preferably 500 ppm or less, even more preferably 250 ppm or less, and even more preferably 200 ppm or less. The lower limit of the total amount of alkali metals and alkaline earth metals may be 1 ppm, 5 ppm, or 10 ppm. That is, the total amount of alkali metals and alkaline earth metals in the polymer resin 62 is preferably 1 ppm to 1000 ppm, more preferably 1 ppm to 700 ppm, even more preferably 1 ppm to 500 ppm, even more preferably 5 ppm to 250 ppm, and even more preferably 10 ppm to 200 ppm.

[0101] The total amount of alkali metals is preferably 700 ppm or less, more preferably 500 ppm or less, and further preferably 300 ppm or less, 250 ppm or less, 200 ppm or less, 150 ppm or less, and 120 ppm or less, in that order. The amounts of potassium, sodium, and lithium are each preferably 500 ppm or less, more preferably 300 ppm or less, even more preferably 250 ppm or less, even more preferably 200 ppm or less, still more preferably 150 ppm or less, and even more preferably 120 ppm or less. In particular, the amount of sodium is preferably 100 ppm or less, more preferably 70 ppm or less, even more preferably 50 ppm or less, even more preferably 40 ppm or less, even more preferably 30 ppm or less, and even more preferably 20 ppm or less. The preferred range of the lithium amount is the same as the preferred range listed for the sodium amount. It is also preferable that both the amount of sodium and the amount of lithium are within the above ranges.

[0102] The preferred range of the total amount of alkaline earth metals is the same as the preferred range listed for the total amount of alkali metals. The amounts of calcium and magnesium are each preferably 500 ppm or less, more preferably 300 ppm or less, even more preferably 200 ppm or less, even more preferably 100 ppm or less, and even more preferably 50 ppm or less. At least one of the amounts of calcium and magnesium is preferably 70 ppm or less, more preferably 50 ppm or less, even more preferably 40 ppm or less, even more preferably 30 ppm or less, even more preferably 20 ppm or less, and even more preferably 15 ppm or less. It is preferable that both the amounts of calcium and magnesium are within the above-mentioned ranges. Furthermore, it is preferable that the amounts of sodium, lithium, calcium, and magnesium are all within the above-mentioned individually preferred ranges, and each or all of lithium, calcium, and magnesium may be 10 ppm or less, or 5 ppm or less.

[0103] By keeping the alkali metals and alkaline earth metals within the above ranges, it is possible to obtain an excellent polymer resin composition in which the recovered polymer resin 62 has high thermal stability, is less discolored when remelted during use, and contains less foreign matter due to residual metals.

[0104] The elemental amounts of alkali metals and alkaline earth metals can be measured, for example, by the following method. First, a sample of the recovered polymer resin formed into a sheet is pretreated as described below to prepare a measurement solution. The element concentrations in the obtained measurement solution are then measured under the following conditions using an inductively coupled plasma (ICP) optical emission spectrometer (SPECTROBLUE, manufactured by Hitachi High-Tech Science Corporation), and the element contents in the sample are calculated. (Pretreatment) The sample of the recovered polymer resin formed into a sheet is weighed into a platinum crucible and pre-carbonized to 400°C on a hot plate. Then, an ashing treatment is carried out at 550°C for 8 hours using a Yamato Scientific electric furnace, Model FO610. After ashing, small amounts of 6.0 N hydrochloric acid and hydrofluoric acid are added, and acid decomposition is carried out on a hot plate, followed by heat treatment until the acids are completely evaporated. After acid decomposition is complete, the solution obtained by adjusting the volume to the required volume using 20 mL of 1.2 N hydrochloric acid is used as the measurement solution. (ICP optical emission analysis conditions) Plasma power: 1400 W Plasma gas: 12.0 L / min Auxiliary gas: 1.0 L / min Nebulizer: Crossflow nebulizer Chamber: Scott chamber Measurement wavelength (nm): Mg: 280.27 Ca: 315.887 K: 766.491 Na: 589.592 Li: 670.78

[0105] The higher the recovery rate of the polymer resin 62 recovered by the polymer resin recovery devices 1, 11, 12, and 13, the better, with the upper limit being 100% by mass, preferably 1% by mass or more, more preferably 5% by mass or more, even more preferably 7% by mass or more, and even more preferably 10% by mass or more. The recovery rate of the polymer resin 62 can be calculated from the content (parts by mass) of the polymer resin in the composite material 22 before the heat treatment and the amount (parts by mass) of the recovered polymer resin 62. Alternatively, the recovery rate of the polymer resin 62 can be calculated by recovering the polymer resin 62 after the heat treatment, measuring its weight (B parts by weight), and using the weight (A parts by weight) of the composite material 22 before the heat treatment and the weight ratio (C%) of the polymer resin in the composite material 22 before the heat treatment, using the following formula: Recovery rate (%) = {B / [A x (C / 100)]} x 100

[0106] The degree of deterioration of the polymer resin 62 recovered by the polymer resin recovery devices 1, 11, 12, and 13 can be confirmed by its viscosity (e.g., relative viscosity, intrinsic viscosity). Because viscosity and the molecular weight of a resin are proportional, the higher the viscosity, the higher the molecular weight of the recovered polymer resin 62, i.e., the more hydrolysis is suppressed and the polymer state is maintained. Specifically, if the polymer resin 62 is a polyamide-based resin, a relative viscosity of 1.3 or higher (preferably 1.5 or higher, more preferably 1.7 or higher, even more preferably 1.9 or higher, even more preferably 2.1 or higher, and even more preferably 2.3 or higher) indicates that the polyamide-based resin is suitable for material recycling. If the polymer resin 62 is a polyester-based resin, a relative viscosity of 0.3 dL / g or higher (preferably 0.5 dL / g or higher, more preferably 0.7 dL / g or higher) indicates that the polyester-based resin is suitable for material recycling.

[0107] The relative viscosity (RV) of the polymer resin 62 can be calculated by dissolving 0.25 g of the polymer resin in 46 g of 96% sulfuric acid, placing 10 ml of this solution in an Oswald viscosity tube, measuring at 20° C., and using the following formula: RV=T / T0 (RV: relative viscosity, T: dripping time of the sample solution, T0: dripping time of the solvent).

[0108] The intrinsic viscosity (η) of the polymer resin 62 can be determined by dissolving 0.1 g of the polymer resin in 25 mL of a mixed solvent of phenol / 1,1,2,2-tetrachloroethane (60 / 40 (weight ratio)) and measuring the viscosity at 30° C. using an Ostwald viscometer.

[0109] When the relative viscosity (RV0) of the polymer resin before heat treatment can be measured, it is preferable that the ratio (RV / RV0) of RV (relative viscosity of the recovered polymer resin 62) to RV0 is 0.4 or more (preferably 0.5 or more, more preferably 0.6 or more, even more preferably 0.7 or more, and even more preferably 0.8 or more). If the value of RV / RV0 is within the above range, the polymer resin 62 recovered by the polymer resin recovery devices 1, 11, 12, and 13 is suppressed in deterioration and can be said to be a polymer resin that is suitable for use in material recycling. When the intrinsic viscosity (η0) of the polymer resin before heat treatment can be measured, it is preferable that the ratio (η / η0) of η (intrinsic viscosity of the recovered polymer resin 62) to η0 is 0.3 or more (preferably 0.5 or more, more preferably 0.7 or more). If the value of η / η0 is within the above range, it can be said that the polymer resin 62 recovered by the polymer resin recovery devices 1, 11, 12, and 13 is suppressed in deterioration and can be said to be a polymer resin that is suitable for use in material recycling.

[0110] The polymer resin 62, which can be suitably used for material recycling, can be reused without further processing such as polymerization, which is advantageous from the viewpoint of energy costs and has particularly high recyclability.

[0111] The uses of the polymer resin recovered by the polymer resin recovery device of the present invention are not particularly limited because deterioration is suppressed. For example, the polymer resin can be reused by decomposing it into monomers and repolymerizing it (chemical recycling), or it can be reused by melting it and re-pelletizing it without decomposing it into monomers (material recycling). From the viewpoint of energy costs, it is preferable to use the polymer resin for material recycling.

[0112] The polymer resin (preferably polyamide-based resin or polyester-based resin) recovered by the polymer resin recovery device of the present invention can be chemically recycled or materially recycled to form recycled products containing the polymer resin as at least a part of the raw material.

[0113] This application claims the benefit of priority based on Japanese Patent Application Nos. 2023-183802, 2023-183803, 2024-097737, and 2024-162410, filed on October 26, 2023. The entire contents of the specifications of Japanese Patent Application Nos. 2023-183802, 2023-183803, 2024-097737, and 2024-162410, filed on October 26, 2023, and 2024-162410, filed on September 19, 2024, are incorporated herein by reference.

[0114] The present invention will be described in more detail below with reference to examples. However, the present invention is not limited to the following examples, and it is of course possible to carry out the invention by making appropriate modifications within the scope of the above and below-described aims, and all such modifications are included in the technical scope of the present invention.

[0115] In the following examples, a composite material was processed to recover a polymer resin using the polymer resin recovery apparatus 12 shown in Figure 3, and in the comparative examples, a composite material was processed using an apparatus that was the same as the polymer resin recovery apparatus 12 shown in Figure 3 except that the separation section 2b and the water flow generation section 8 were removed. In the following examples and comparative examples, the following polyamide resin airbag fabric 1 was used as the composite material.

[0116] (Polyamide Resin Airbag Fabric 1) A plain weave fabric was obtained using polyamide 66 multifilament yarn with a raw yarn strength of 8.4 cN / dtex, a total fineness of 470 dtex, and 68 filaments, with a warp density of 46 threads / 2.54 cm, a weft density of 46 threads / 2.54 cm, and a cover factor of 1994. One side of the plain weave fabric (base fabric) was coated with an addition polymerization type solventless vinyl methyl silicone resin with a resin viscosity of 14,000 mPa sec and dried at 200°C for 1 minute, resulting in a resin coating amount of 25 g / m. 2 Thus, a polyamide resin airbag fabric 1 was obtained. The weight ratio of polyamide resin in the polyamide resin airbag fabric 1 was 87%.

[0117] In the following examples and comparative examples, the polyamide resin, which is a polymer resin recovered from the polyamide resin airbag fabric 1, was evaluated in the following manner.

[0118] (Recovery Rate) After the heat treatment, the polyamide resin separated from the silicone resin in the heat treatment section 2a was recovered by the separation section 2b. The weight of the recovered polyamide resin (B parts by weight) was measured, and the recovery rate was calculated using the weight of the sample before treatment (A parts by weight) and the weight ratio of the polyamide resin in the sample before treatment (C%) according to the following formula: Recovery rate (%) = {B / [A x (C / 100)]} x 100

[0119] (Silicone Content) After the heat treatment, the polyamide resin separated from the silicone resin by the separation section 2b was recovered in the heat treatment section 2a. The recovered polyamide resin was powdered by freeze-grinding to prepare a measurement sample, which was then measured using an optical X-ray measurement device (XL3t-950S manufactured by Thermo Fisher Scientific). Specifically, the measurement was performed in Cu / Zn mode in the mineral mode (FP method) with a measurement field of view of an 8 mm diameter spot. The amount of Si element (ppm by mass) in the measurement sample was evaluated as the silicone content. Note that the silicone content of the polyamide resin airbag fabric 1 before the above measurement was 250,000 ppm by mass.

[0120] (Relative Viscosity) After the heat treatment, the polyamide resin separated from the silicone resin by the separation section 2b was recovered in the heat treatment section 2a. 0.25 g of the recovered polyamide resin was dissolved in 46 g of 96% sulfuric acid, and 10 mL of this solution was placed in an Oswald viscosity tube and measured at 20°C. The relative viscosity was calculated using the following formula. Since the relative viscosity and the molecular weight of the resin are proportional, the higher the relative viscosity, the higher the molecular weight of the recovered polyamide resin, which means that it maintains a polymeric state. RV = T / T0 (RV: relative viscosity, T: dripping time of the sample solution, T0: dripping time of the solvent)

[0121] (Elemental Amounts of Alkali Metals and Alkaline Earth Metals) A sample of the recovered polyamide resin sheet was pretreated as follows to prepare a measurement solution. The element concentrations in the resulting measurement solution were then measured under the following conditions using a high-frequency inductively coupled plasma (ICP) emission spectrometer (SPECTROBLUE, manufactured by Hitachi High-Tech Science Corporation), and the element contents in the sample were calculated. ((Pretreatment)) The recovered polyamide resin sheet sample was weighed into a platinum crucible and pre-carbonized to 400°C on a hot plate. Then, an ashing treatment was carried out at 550°C for 8 hours using a Yamato Scientific electric furnace, Model FO610. After ashing, small amounts of 6.0 N hydrochloric acid and hydrofluoric acid were added, and the sample was subjected to acid decomposition on a hot plate and heated until the acid was completely evaporated. After acid decomposition, the solution was adjusted to volume with 20 mL of 1.2 N hydrochloric acid, and the resulting solution was used as the measurement solution. (ICP optical emission analysis conditions) Plasma power: 1400 W Plasma gas: 12.0 L / min Auxiliary gas: 1.0 L / min Nebulizer: Crossflow nebulizer Chamber: Scott chamber Measurement wavelength (nm): Mg: 280.27 Ca: 315.887 K: 766.491 Na: 589.592 Li: 670.78

[0122] Example 1 The polyamide resin airbag fabric 1 was cut into 40 mm square pieces. 10 g of the cut sample was placed in the heat treatment section 2a (internal volume: 500 mL) of the high-pressure hot water treatment device 12 along with 300 mL of water. The cut sample was submerged in water using the first filter element 21 (a metal filter containing aluminum with a 2 mm mesh size) of the separation section 2b. While stirring with the stirring blade 81 to generate an upward water flow, the sample was heated to 220°C using the heating mechanism 23. The pressure at this time was 2.3 MPa. After 10 minutes of heat treatment, the heat treatment section 2a was cooled to room temperature using a spot cooler (not shown), and the separated polyamide resin was recovered. The evaluation results of the recovered polyamide resin are shown in Table 1. In Example 1, the polyamide resin recovery rate was 39%, and the recovered polyamide resin had a relative viscosity of 2.06. Therefore, when recovering polymer resin using the polymer resin recovery device 12 of Example 1, it can be said that the silicone resin and polyamide resin can be easily separated, and furthermore, the polyamide resin can be recovered in a polymer state (a state in which deterioration is suppressed).

[0123] (Examples 2 to 4) In Examples 2 to 4, polyamide resin was recovered in the same manner as in Example 1, except that the conditions were changed as shown in Table 1. The evaluation results of the recovered polyamide resin are shown in Table 1. When recovering polymer resin using polymer resin recovery device 12 in Examples 2 to 4, it was possible to easily separate the silicone resin and polyamide resin, and furthermore, it was possible to recover the polyamide resin in a polymer state (a state in which deterioration was suppressed).

[0124] The potassium content of the polyamide resins recovered in Examples 1 to 4 was 100 ppm by mass, the sodium content was 10 ppm by mass, and the lithium, calcium, and magnesium contents were all 2 ppm by mass or less.

[0125] Comparative Example 1 In Comparative Example 1, polyamide resin was recovered in the same manner as in Example 1, except that a polymer resin recovery device was used that did not have the separation section 2b and the water flow generating section 8. However, in Comparative Example 1, the polyamide resin that had melted due to the heat treatment adhered to the silicone resin when solidified, and it was not possible to recover the polyamide resin that had separated from the silicone resin.

[0126]

[0127] From the above, it has been found that the polymer resin recovery device disclosed herein and the recovery method using the polymer resin recovery device can easily recover polymer resin that is suitable for material recycling because it is in a polymer state (a state in which deterioration is suppressed) from airbag fabric made of polymer resin, which is a composite material.

[0128] DESCRIPTION OF SYMBOLS 1, 11, 12, 13 Polymer resin recovery device 2a Heat treatment section 2b Separation section 21 First filter element 22 Composite material 23 Heating mechanism 3 Hot water supply section 4 Discharge section 5, 51 Cooling mechanism 6 Recovery section 61 Second filter element 62 Solidified polymer resin 7a Hot water preparation mechanism 7b High-pressure hot water preparation mechanism 71 Pressure adjustment mechanism (high-pressure hot water preparation mechanism) 72 Heating mechanism (high-pressure hot water preparation mechanism) 73 Heating mechanism (hot water preparation mechanism) 8 Water flow generation section 81 Stirring blade 82 Pump 9 Water storage tank 91 Recovered water storage tank 111, 112 Residue removal filter 121, 122, 123, 124, 125 Valve 131 Check valve 141 Motor

Claims

1. An apparatus for treating a composite material containing a polymer resin with high-pressure hot water and recovering the polymer resin from the composite material, comprising: a heat treatment section that contains the composite material and brings it into contact with high-pressure hot water; a separation section that has a first filter member that allows the polymer resin melted in the heat treatment section to pass while restricting the movement of the composite material and the movement of unmelted material in the heat treatment section; and a water flow generation section that sends a water flow to the separation section.

2. The polymer resin recovery device according to claim 1, further comprising a cooling mechanism for cooling the molten polymer resin separated in said separation section together with high-pressure hot water to solidify the polymer resin.

3. The polymer resin recovery device according to claim 2, further comprising a recovery section for recovering the solidified polymer resin.

4. The polymer resin recovery device according to claim 3, wherein the recovery section is provided with a second filter member for filtering out the solidified polymer resin.

5. The polymer resin recovery apparatus according to claim 1, further comprising a hot water supply section for supplying hot water to the heat treatment section.

6. The polymer resin recovery apparatus according to claim 5, further comprising a hot water preparation mechanism upstream of said hot water supply section.

7. The polymer resin recovery device according to claim 1, wherein the heat treatment section has a heating mechanism.

8. The polymer resin recovery apparatus according to claim 1, wherein the water flow generating section is an agitating blade provided in the heat treatment section.

9. The polymer resin recovery device according to claim 1, further comprising a discharge section for discharging the polymer resin molten in the heat treatment section together with high-pressure hot water.

10. The polymer resin recovery device according to claim 1, wherein the first filter member is detachable.

11. The polymer resin recovery apparatus according to claim 1, wherein said first filter member is made of metal.

12. The polymer resin recovery device according to claim 11, wherein the metal is made of at least one member selected from the group consisting of stainless steel and aluminum.

13. The first filter member has a plurality of through holes (A), and the opening area of ​​each of the through holes (A) is 0.001 mm 2 ~200cm 2 The polymer resin recovery device according to claim 1 , 14. The second filter member has a plurality of through holes (B), and the opening area of ​​each of the through holes (B) is 0.001 mm 2 ~1cm 2 The polymer resin recovery device according to claim 4, 15. The polymer resin recovery device according to claim 1, wherein the internal volume of the heat treatment section is 0.5L to 3000L.

16. The polymer resin recovery device according to claim 3, comprising a plurality of said recovery sections.

17. The polymer resin recovery apparatus according to claim 1, comprising a plurality of said heat treatment sections.

18. A method for recovering a polymer resin from a composite material containing the polymer resin, using the polymer resin recovery device according to any one of claims 1 to 17.

19. The method for recovering polymeric resin according to claim 18, wherein the composite material is an airbag fabric containing silicone and the polymeric resin is a polyamide-based resin or a polyester-based resin.

20. A recycled product, at least part of whose raw material is a polyamide resin or a polyester resin obtained by the method according to claim 19.

21. Use of the polymer resin recovery device according to any one of claims 1 to 17 to recover a polymer resin from a composite material containing the polymer resin.

22. The use of the polymer resin recovery device according to claim 21, wherein the composite material is an airbag fabric containing silicone, and the polymer resin is a polyamide-based resin or a polyester-based resin.