Method for recycling of decommissioned wind turbine blades and thermal insulation material

Abstract

The present application belongs to the technical field of wind turbine blade recycling and reuse, and discloses a resource utilization method of decommissioned wind turbine blades and a thermal insulation material. The method comprises the following steps: cutting and crushing the decommissioned wind turbine blade materials, and screening to obtain blade glass fiber reinforced plastic waste; dispersing the blade glass fiber reinforced plastic waste into water, and performing ultrasonic crushing treatment to obtain a glass fiber reinforced plastic dispersion liquid; mixing a sodium alginate / sodium hyaluronate mixed solution with the glass fiber reinforced plastic dispersion liquid to obtain a mixed dispersion liquid; adding a calcium compound to the mixed dispersion liquid, and stirring until the calcium compound is uniformly dispersed to obtain a uniform dispersion liquid; adding a crosslinking agent to the uniform dispersion liquid, and allowing the crosslinking agent to stand until complete gelation is achieved to obtain a gelation product; and freeze-drying the gelation product to obtain a glass fiber reinforced plastic-sodium alginate composite aerogel thermal insulation material. The present application realizes effective conversion and recycling of resources of decommissioned wind turbine blades, and effectively reduces the environmental pollution caused by recycling of wind turbine blades.

Description

Technical Field

[0001] This invention belongs to the field of wind turbine blade recycling and reuse technology, and specifically relates to a method for the resource utilization of retired wind turbine blades and a heat insulation material. Background Technology

[0002] With the continuous development of the wind power industry, the scale of wind turbines and wind turbine blades is constantly increasing. As wind turbines reach the end of their service life, the number of retired wind turbines and wind turbine blades that need to be processed will also increase dramatically. Therefore, the recycling and processing of retired wind turbine blades is a key issue that the wind power industry urgently needs to solve.

[0003] The main material of wind turbine blades is fiberglass, a composite material of epoxy resin and glass fiber. Currently, the main methods for reusing retired wind turbine blades include direct recycling, energy recovery, and reprocessing into building materials. Direct recycling involves crushing or cutting the blades into small pieces, then chemically or physically processing them to extract the glass fiber and resin for use in manufacturing new composite products. Energy recovery involves using retired blades as fuel, converting them into energy, such as heat or combustible gas, through pyrolysis or gasification. Reprocessing into building materials involves processing the blade material into building materials, such as reinforcing concrete or as part of a building structure. However, the above-mentioned existing recycling methods generally cause serious environmental pollution. Given the large number of retired wind turbine blades to be recycled in the future, it is crucial to continue searching for zero-waste recycling methods. Summary of the Invention

[0004] In view of the technical problems existing in the prior art, the present invention provides a method for resource utilization of retired wind turbine blades and a heat insulation material, so as to solve the technical problem of serious environmental pollution that exists in the existing wind turbine blade recycling methods.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0006] This invention provides a method for the resource utilization of retired wind turbine blades, comprising:

[0007] The material of retired wind turbine blades is cut, crushed, and screened to obtain fiberglass waste fragments of the blades.

[0008] The waste fiberglass blade fragments were dispersed in water and ultrasonically crushed to obtain a fiberglass dispersion.

[0009] The sodium alginate / sodium hyaluronate mixed solution was mixed with the fiberglass dispersion to obtain the mixed dispersion;

[0010] Add calcium compounds to the mixed dispersion and stir until the dispersion is uniform to obtain a homogeneous dispersion.

[0011] A cross-linking agent is added to a uniform dispersion, and the mixture is allowed to stand until cross-linking is complete to obtain a gelled product.

[0012] The gelation product was freeze-dried to obtain a fiberglass-sodium alginate composite aerogel insulation material.

[0013] Furthermore, the particle size of the waste fiberglass blade fragments is greater than 50 mesh; the particle size of the waste fiberglass blade fragments in the fiberglass dispersion is 10-100 μm.

[0014] Furthermore, in the process of dispersing the waste fiberglass blade fragments into water and ultrasonically crushing them to obtain a fiberglass dispersion, an ultrasonic crusher is used for ultrasonic crushing treatment.

[0015] Furthermore, the mass ratio of sodium alginate, sodium hyaluronate and fiberglass in the mixed dispersion is (2-4):1:(10-12).

[0016] Furthermore, during the process of adding calcium compounds to the mixed dispersion, the amount of calcium compounds added is 1%-3% of the total mass of sodium alginate, sodium hyaluronate, and fiberglass in the mixed dispersion.

[0017] Furthermore, the calcium compounds are one of calcium carbonate, calcium chloride, and calcium sulfate.

[0018] Furthermore, the crosslinking agent is D-gluconic acid lactone.

[0019] Furthermore, a crosslinking agent is added to the uniform dispersion, and the mixture is allowed to stand for crosslinking until complete gelation is achieved. In the process of obtaining the gelled product, the crosslinking is carried out at 25-60℃ for 30-600 min.

[0020] Furthermore, in the process of freeze-drying the gelled product to obtain the fiberglass-sodium alginate composite aerogel insulation material, the freeze-drying temperature is -40~-80℃ and the time is 24-120h.

[0021] The present invention also provides a thermal insulation material, wherein the thermal insulation material is a fiberglass-sodium alginate composite aerogel thermal insulation material; the fiberglass-sodium alginate composite aerogel thermal insulation material is prepared by the resource utilization method of the retired wind turbine blades described above.

[0022] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0023] This invention provides a method for the resource utilization of retired wind turbine blades. Using retired wind turbine blade materials as raw materials, sodium alginate and sodium hyaluronate are added, and freeze-drying technology is used to obtain a fiberglass-sodium alginate composite aerogel insulation material. This transforms waste blades into high-performance insulation materials, achieving effective conversion and resource recycling of retired wind turbine blades, and effectively reducing the environmental pollution caused by wind turbine blade recycling. The composite aerogel insulation material has extremely low density, high porosity, and excellent insulation performance, enabling it to effectively block heat transfer while maintaining its lightweight nature, giving it potential application advantages in the field of insulation. Furthermore, the addition of calcium compounds and crosslinking agents achieves gelation of the mixed dispersion. The process is simple, easy to operate, and allows for effective control of the material's structure and properties. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 The image shows a scanning electron microscope (SEM) image of the fiberglass scrap material from the blades in Example 1.

[0026] Figure 2 This is a scanning electron microscope image of the fiberglass-sodium alginate composite aerogel insulation material in Example 1 at 200 μm.

[0027] Figure 3 This is a scanning electron microscope image of the fiberglass-sodium alginate composite aerogel insulation material in Example 1 at 10 μm. Detailed Implementation

[0028] To make the technical problems, technical solutions, and beneficial effects solved by this application clearer, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0029] This invention provides a method for the resource utilization of retired wind turbine blades, comprising the following steps:

[0030] Step 1: Physically cut and crush the retired wind turbine blade material, and screen the crushed fiberglass waste to obtain blade fiberglass waste fragments; wherein the particle size of the blade fiberglass waste fragments is greater than 50 mesh.

[0031] Step 2: Disperse the scrap of fiberglass blades into distilled water and crush it using an ultrasonic crusher to obtain a fiberglass dispersion; wherein the particle size of the scrap of fiberglass blades in the fiberglass dispersion is 10-100μm.

[0032] Step 3: Dissolve sodium alginate and sodium hyaluronate in distilled water to obtain a sodium alginate / sodium hyaluronate mixed solution; mix the sodium alginate / sodium hyaluronate mixed solution with fiberglass dispersion to obtain a mixed dispersion; wherein the mass ratio of sodium alginate, sodium hyaluronate and fiberglass in the mixed dispersion is (2-4):1:(10-12).

[0033] Step 4: Add the calcium compound to the mixed dispersion and stir until evenly dispersed to obtain a uniform dispersion; wherein, the amount of calcium carbonate powder added is 1%-3% of the total mass of sodium alginate, sodium hyaluronate and fiberglass in the mixed dispersion; the calcium compound is one of calcium carbonate, calcium chloride and calcium sulfate.

[0034] Step 5: Add a crosslinking agent to the uniform dispersion, and allow it to stand at 25-60℃ for 30-600 min to crosslink and obtain the gelled product; wherein, the crosslinking agent is D-gluconolactone.

[0035] Step 6: Freeze-dry the gelled product to obtain fiberglass-sodium alginate composite aerogel insulation material; wherein the freeze-drying temperature is -40~-80℃ and the time is 24-120h.

[0036] The principle of resource utilization methods:

[0037] The resource utilization method for retired wind turbine blades described in this invention effectively reduces waste generation and environmental burden by recycling retired wind turbine blades; it transforms waste blades into new thermal insulation materials, realizing resource recycling and improving resource utilization efficiency; specifically, ultrasonic waves are used to crush fiberglass waste, improving its dispersibility and providing favorable conditions for subsequent preparation of a uniform dispersion; using waste fiberglass material as a reinforcing phase of the thermal insulation material not only significantly improves the mechanical strength of the thermal insulation material but also gives it good thermal insulation performance; the addition of sodium alginate and sodium hyaluronate enhances the molding of the fiberglass waste, giving it good thermal insulation performance; the addition of calcium compounds and crosslinking agents achieves gelation of the mixed dispersion, effectively controlling the structure and properties of the material; this invention realizes the resource utilization of retired wind turbine blades without the need for separation or conversion of fiberglass waste, generating no additional waste. The waste is fully utilized through physical, chemical, and physicochemical processes, forming a high-value-added fiberglass-sodium alginate composite aerogel thermal insulation material, which has potential application value in high-performance thermal insulation materials.

[0038] In this invention, retired wind turbine blades are used as raw materials. Sodium alginate and sodium hyaluronate are added, and a fiberglass-sodium alginate composite aerogel insulation material is obtained using freeze-drying technology. This transforms waste blades into high-performance insulation materials, achieving effective conversion and resource recycling of retired wind turbine blades, and effectively reducing environmental pollution from wind turbine blade recycling. The composite aerogel insulation material has extremely low density, high porosity, and excellent insulation performance, allowing it to effectively block heat transfer while remaining lightweight, giving it potential advantages in the field of insulation. Furthermore, the addition of calcium compounds and crosslinking agents enables gelation of the mixed dispersion, a simple and easy-to-operate process that effectively controls the material's structure and properties.

[0039] Example 1

[0040] This embodiment 1 provides a method for the resource utilization of retired wind turbine blades, including the following steps:

[0041] Step 1: Place the decommissioned wind turbine blade material in a high-speed pulverizer for physical cutting, and then pulverize it using a ball mill to obtain the pulverized material; use a 50-mesh standard inspection sieve to screen the pulverized material to obtain blade fiberglass waste fragments with a particle size greater than 50 mesh.

[0042] Step 2: Disperse 5g of fiberglass blade waste fragments into 30mL of distilled water and crush them using an ultrasonic crusher for 2 hours to obtain a fiberglass dispersion; wherein the particle size of the fiberglass blade waste fragments in the fiberglass dispersion is 10-100μm.

[0043] Step 3: Dissolve 1.4g of sodium alginate and 0.44g of sodium hyaluronate in 75mL of distilled water to obtain a sodium alginate / sodium hyaluronate mixed solution; mix the sodium alginate / sodium hyaluronate mixed solution with fiberglass dispersion to obtain a mixed dispersion.

[0044] Step 4: Add 0.2g of calcium carbonate powder to the mixed dispersion and stir at room temperature until it is evenly dispersed to obtain a uniform dispersion.

[0045] Step 5: Add 0.06 mL of D-glucosidase to the uniform dispersion, and allow it to stand at 60°C for 30 min to crosslink, thereby obtaining the gelled product.

[0046] Step 6: Freeze-dry the gelled product at a freeze-drying temperature of -40℃ for 120 hours to obtain fiberglass-sodium alginate composite aerogel insulation material.

[0047] As attached Figure 1 As shown, attached Figure 1 The attached document provides scanning electron microscope (SEM) images of the fiberglass scrap from Example 1; from the attached document... Figure 1 As can be seen, the waste fiberglass blades exhibit a typical fiber and debris structure, with irregular debris particles on the fiber surface.

[0048] As attached Figure 2-3 As shown, attached Figure 2 The image provided is a scanning electron microscope (SEM) image of the fiberglass-sodium alginate composite aerogel insulation material in Example 1 at 200 μm. Figure 3 The image provided is a scanning electron microscope (SEM) image of the fiberglass-sodium alginate composite aerogel insulation material in Example 1 at 10 μm; from the attached image... Figure 2-3 As can be seen, by adding fiberglass, the fiberglass-sodium alginate composite aerogel insulation material retains the original porous network structure with very rough pore walls. Among them, typical rod-shaped glass fibers are arranged interlaced in the aerogel matrix as a skeleton. The fiberglass obtained after mechanical crushing of retired blades is a rod-shaped fiber structure with uneven length. These fibers are richly distributed on the pore walls and are embedded in the pore walls like a brick-and-mortar structure. Fiberglass fragments serve as a reinforcing phase material to support the insulation composite material's resistance to pressure, increasing the compressive strength by more than two times.

[0049] Performance test results explanation:

[0050] The fiberglass-sodium alginate composite aerogel insulation material prepared in Example 1 was tested, and the results were as follows: at 71% compressive strain, the compressive strength of the fiberglass-sodium alginate composite aerogel insulation material reached 1 MPa; wherein, the fiberglass fragments, as the reinforcing phase material, support the insulation composite material's resistance to pressure, increasing the compressive strength by more than two times; the thermal conductivity of the fiberglass-sodium alginate composite aerogel insulation material was only 0.041 W / (m∙K), indicating its excellent thermal insulation performance.

[0051] Example 2

[0052] The method for resource utilization of decommissioned wind turbine blades provided in Embodiment 2 is basically the same as the method in Embodiment 1 above, except that:

[0053] In the mixed dispersion of step 3, the mass ratio of sodium alginate, sodium hyaluronate and fiberglass is 2:1:10; the remaining steps are basically the same and will not be repeated here.

[0054] Performance test results explanation:

[0055] At 71% compressive strain, the compressive strength of the fiberglass-sodium alginate composite aerogel insulation material reaches 1.1 MPa; wherein, fiberglass fragments serve as a reinforcing phase material to support the insulation composite material's resistance to pressure, increasing the compressive strength by more than two times; the thermal conductivity of the fiberglass-sodium alginate composite aerogel insulation material is only 0.040 W / (m∙K).

[0056] Example 3

[0057] The method for resource utilization of decommissioned wind turbine blades provided in this embodiment 3 is basically the same as the method in embodiment 1 above, except that:

[0058] In the mixed dispersion of step 3, the mass ratio of sodium alginate, sodium hyaluronate and fiberglass is 3:1:12; the remaining steps are basically the same and will not be repeated here.

[0059] Performance test results explanation:

[0060] At 71% compressive strain, the compressive strength of the fiberglass-sodium alginate composite aerogel insulation material reaches 1.02 MPa; wherein, fiberglass fragments serve as a reinforcing phase material to support the insulation composite material's resistance to pressure, increasing the compressive strength by more than two times; the thermal conductivity of the fiberglass-sodium alginate composite aerogel insulation material is only 0.042 W / (m∙K).

[0061] Example 4

[0062] The method for resource utilization of decommissioned wind turbine blades provided in this embodiment 4 is basically the same as the method in embodiment 1 above, except that:

[0063] In the mixed dispersion of step 3, the mass ratio of sodium alginate, sodium hyaluronate and fiberglass is 4:1:11; the remaining steps are basically the same and will not be repeated here.

[0064] Performance test results explanation:

[0065] At 71% compressive strain, the compressive strength of the fiberglass-sodium alginate composite aerogel insulation material reaches 1.4 MPa; wherein, fiberglass fragments serve as a reinforcing phase material to support the insulation composite material's resistance to pressure, increasing the compressive strength by more than two times; the thermal conductivity of the fiberglass-sodium alginate composite aerogel insulation material is only 0.039 W / (m∙K).

[0066] Example 5

[0067] The method for resource utilization of decommissioned wind turbine blades provided in Embodiment 5 is basically the same as the method in Embodiment 1 above, except that:

[0068] In step 4, the calcium compound added is calcium chloride, and the amount of calcium chloride added is 1% of the total mass of sodium alginate, sodium hyaluronate and fiberglass in the mixed dispersion.

[0069] Performance test results explanation:

[0070] At 71% compressive strain, the compressive strength of the fiberglass-sodium alginate composite aerogel insulation material reaches 0.99 MPa; wherein, fiberglass fragments serve as a reinforcing phase material to support the insulation composite material's resistance to pressure, increasing the compressive strength by more than two times; the thermal conductivity of the fiberglass-sodium alginate composite aerogel insulation material is only 0.043 W / (m∙K).

[0071] Example 6

[0072] The method for resource utilization of decommissioned wind turbine blades provided in Embodiment 6 is basically the same as the method in Embodiment 1 above, except that:

[0073] In step 4, the added calcium compound is calcium sulfate, and the amount of calcium chloride added is 2% of the total mass of sodium alginate, sodium hyaluronate and fiberglass in the mixed dispersion.

[0074] Performance test results explanation:

[0075] At 71% compressive strain, the compressive strength of the fiberglass-sodium alginate composite aerogel insulation material reaches 0.93 MPa; wherein, fiberglass fragments serve as a reinforcing phase material to support the insulation composite material's resistance to pressure, increasing the compressive strength by more than two times; the thermal conductivity of the fiberglass-sodium alginate composite aerogel insulation material is only 0.048 W / (m∙K).

[0076] Example 7

[0077] The method for resource utilization of decommissioned wind turbine blades provided in Embodiment 7 is basically the same as the method in Embodiment 1 above, except that:

[0078] In step 5, a crosslinking agent is added to the uniform dispersion, and the mixture is allowed to stand for crosslinking until complete gelation is achieved to obtain the gelled product. In this process, the crosslinking is carried out at 35°C for 400 min.

[0079] Performance test results explanation:

[0080] At 71% compressive strain, the compressive strength of the fiberglass-sodium alginate composite aerogel insulation material reaches 1.2 MPa; wherein, fiberglass fragments serve as a reinforcing phase material to support the insulation composite material's resistance to pressure, increasing the compressive strength by more than two times; the thermal conductivity of the fiberglass-sodium alginate composite aerogel insulation material is only 0.040 W / (m∙K).

[0081] Example 8

[0082] The method for resource utilization of decommissioned wind turbine blades provided in this embodiment 8 is basically the same as the method in embodiment 1 above, except that:

[0083] In step 5, a crosslinking agent is added to the uniform dispersion, and the mixture is allowed to stand for crosslinking until complete gelation is achieved to obtain the gelled product. In this process, the crosslinking is carried out at 25°C for 600 min.

[0084] Performance test results explanation:

[0085] At 71% compressive strain, the compressive strength of the fiberglass-sodium alginate composite aerogel insulation material reaches 1.11 MPa; wherein, fiberglass fragments serve as a reinforcing phase material to support the insulation composite material's resistance to pressure, increasing the compressive strength by more than two times; the thermal conductivity of the fiberglass-sodium alginate composite aerogel insulation material is only 0.043 W / (m∙K).

[0086] Example 9

[0087] The method for resource utilization of decommissioned wind turbine blades provided in Embodiment 9 is basically the same as the method in Embodiment 1 above, except that:

[0088] In step 6, the freeze-drying temperature is -50℃ and the time is 60h.

[0089] Performance test results explanation:

[0090] At 71% compressive strain, the compressive strength of the fiberglass-sodium alginate composite aerogel insulation material reaches 1.05 MPa; wherein, fiberglass fragments serve as a reinforcing phase material to support the insulation composite material's resistance to pressure, increasing the compressive strength by more than two times; the thermal conductivity of the fiberglass-sodium alginate composite aerogel insulation material is only 0.041 W / (m∙K).

[0091] Example 10

[0092] The method for resource utilization of decommissioned wind turbine blades provided in this embodiment 10 is basically the same as the method in embodiment 1 above, except that:

[0093] In step 6, the freeze-drying temperature is -80℃ and the time is 24 minutes.

[0094] Performance test results explanation:

[0095] At 71% compressive strain, the compressive strength of the fiberglass-sodium alginate composite aerogel insulation material reaches 1.01 MPa; wherein, fiberglass fragments serve as a reinforcing phase material to support the insulation composite material's resistance to pressure, increasing the compressive strength by more than two times; the thermal conductivity of the fiberglass-sodium alginate composite aerogel insulation material is only 0.044 W / (m∙K).

[0096] The resource utilization method for retired wind turbine blades described in this invention mixes fiberglass waste with sodium alginate / sodium hyaluronate and treats it with calcium compounds and crosslinking agents to prepare a composite aerogel material with excellent thermal insulation properties. The raw materials used are mainly retired wind turbine blades and sodium alginate and sodium hyaluronate, two natural polymer materials. No toxic or harmful chemicals are used in the preparation process, so the environmental impact is minimal, allowing for the effective conversion and utilization of fiberglass waste. The prepared fiberglass-sodium alginate composite aerogel thermal insulation material has broad application prospects in construction, transportation, aerospace and other fields. In particular, the application of ultrasonic crushing and freeze-drying technologies helps to obtain a more uniform and finer material structure.

[0097] The above embodiments are merely one of the implementation methods for achieving the technical solution of the present invention. The scope of protection claimed by the present invention is not limited to this embodiment, but also includes any variations, substitutions and other implementation methods that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention.

Claims

1. A method for the resource utilization of retired wind turbine blades, characterized in that, include: The material of retired wind turbine blades is cut, crushed, and screened to obtain fiberglass waste fragments of the blades. The waste fiberglass blade fragments were dispersed in water and ultrasonically crushed to obtain a fiberglass dispersion. The sodium alginate / sodium hyaluronate mixed solution was mixed with the fiberglass dispersion to obtain the mixed dispersion; Add calcium compounds to the mixed dispersion and stir until the dispersion is uniform to obtain a homogeneous dispersion. A cross-linking agent is added to a uniform dispersion, and the mixture is allowed to stand until cross-linking is complete to obtain a gelled product. The gelation product was freeze-dried to obtain a fiberglass-sodium alginate composite aerogel insulation material. The mass ratio of sodium alginate, sodium hyaluronate and fiberglass in the mixed dispersion is (2-4):1:(10-12). During the process of adding calcium compounds to the mixed dispersion, the amount of calcium compounds added is 1%-3% of the total mass of sodium alginate, sodium hyaluronate, and fiberglass in the mixed dispersion; In the process of adding a crosslinking agent to a uniform dispersion and allowing it to stand for crosslinking until complete gelation is achieved, the gelled product is obtained by standing for crosslinking at 25-60℃ for 30-600 min. In the process of freeze-drying the gelation product to obtain fiberglass-sodium alginate composite aerogel insulation material, the freeze-drying temperature is -40~-80℃ and the time is 24-120h.

2. The method for resource utilization of decommissioned wind turbine blades according to claim 1, characterized in that, The particle size of the waste fiberglass blade fragments is greater than 50 mesh; the particle size of the waste fiberglass blade fragments in the fiberglass dispersion is 10-100 μm.

3. The method for resource utilization of decommissioned wind turbine blades according to claim 1, characterized in that, In the process of dispersing the waste fiberglass blade fragments into water and ultrasonically crushing them to obtain a fiberglass dispersion, an ultrasonic crusher is used for ultrasonic crushing treatment.

4. The method for resource utilization of decommissioned wind turbine blades according to claim 1, characterized in that, Calcium compounds are one of calcium carbonate, calcium chloride, and calcium sulfate.

5. A method for resource utilization of decommissioned wind turbine blades according to claim 1, characterized in that, The crosslinking agent is D-glucosidase.

6. A heat insulation material, characterized in that, The thermal insulation material is a fiberglass-sodium alginate composite aerogel thermal insulation material; the fiberglass-sodium alginate composite aerogel thermal insulation material is prepared by the resource utilization method of retired wind turbine blades as described in any one of claims 1-5.

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