WO2024103672A1

WO2024103672A1 - Method for enriching glass fibers in waste wind turbine blades

Info

Publication number: WO2024103672A1
Application number: PCT/CN2023/096219
Authority: WO
Inventors: 刘向辉; 何发泉
Original assignee: 国能龙源环保有限公司
Priority date: 2022-11-14
Filing date: 2023-05-25
Publication date: 2024-05-23
Also published as: CN115447028A; CN115447028B

Abstract

The present invention relates to the field of recovery of retired wind turbine blades, and discloses a method for enriching glass fibers in waste wind turbine blades. The method comprises: (1) crushing waste wind turbine blades to obtain a crushed material, then sieving same, and collecting the crushed material, which has a particle size of 20-200 mesh; (2) mixing the collected crushed material with a particle size of 20-200 mesh with water, then stirring same at 40-80°C for 2-16 h, and sieving same with a 140-mesh sieve to obtain an oversize product A; (3) mixing the oversize product A with an organic solvent, then stirring same at 40-80°C for 2-8 h, and sieving same with an 80-mesh sieve to obtain an oversize product B; and (4) mixing the oversize product B with ethyl alcohol, wherein the liquid-solid ratio of the ethyl alcohol to the oversize product B is 30-50 mL/g, then stirring same at 50-80°C for 2-7 h, filtering same, and drying a solid obtained by means of filtration at 60-150°C for 2-24 h. By means of the method of the present invention, glass fibers in waste wind turbine blades can be fully utilized; and as the glass fibers in the wind turbine blades are enriched via a simple and fast means, the subsequent recycling thereof is facilitated.

Description

A method for enriching glass fibers in discarded wind turbine blades

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of Chinese patent application 202211417649.4 filed on November 14, 2022, the contents of which are incorporated herein by reference.

Technical Field

The invention relates to the field of recycling retired wind turbine blades, and in particular to a method for enriching glass fibers in discarded wind turbine blades.

Background technique

Wind power generation is an important way for my country to develop low-carbon power. At present, the proportion of wind power generation in my country and even in the world is increasing year by year. The main components of wind power generation are wind turbine blades, which account for a large proportion of the power generation cost.

At present, the main material of wind turbine blades is a composite material formed by fiber and resin, and the fiber is mainly glass fiber. Early wind turbine blades were mainly made of glass fiber, and the mass proportion of glass fiber usually reached 60%, but there was a large amount of resin bonding, which was extremely unfavorable for the subsequent fiber utilization. At the same time, the complete resin and fiber separation process is costly and the process is long, making it difficult to fully apply.

Summary of the invention

The purpose of the present invention is to overcome the difficulty of glass fiber in existing waste wind turbine blades. In order to solve the separation problem, a method for collecting glass fibers from discarded wind turbine blades is provided. This method can greatly improve the applicable fields and application scope of the product by further enriching the fibers and increasing the glass fiber content of the product and appropriately reducing the resin content, thereby achieving the purpose of low-cost resource utilization.

In order to achieve the above object, the present invention provides a method for enriching glass fibers in waste wind turbine blades, the method comprising the following steps:

(1) crushing the discarded wind turbine blades to obtain crushed materials, and controlling the proportion of particles with a particle size of more than 20 mesh in the crushed materials to be 10-30% by weight, and the proportion of particles with a particle size of 20-200 mesh to be ≥20% by weight, and then screening and collecting the crushed materials with a particle size of 20-200 mesh;

(2) mixing the collected pulverized material with a particle size of 20-200 mesh with water, stirring at 40-80° C. for 2-16 hours, and then passing through a 140-mesh sieve to obtain an oversize material A;

(3) mixing the oversize A with an organic solvent, stirring at 40-80° C. for 2-8 hours, and then passing through an 80-mesh sieve to obtain an oversize B;

(4) Mix the sieve material B with ethanol, wherein the liquid-to-solid ratio of the ethanol to the sieve material B is 30-50 mL/g, and then stir at 50-80° C. for 2-7 h, followed by filtering, and drying the filtered solid at 60-150° C. for 2-24 h.

Preferably, in step (1), the proportion of particles with a particle size of >20 mesh in the pulverized material is controlled to be 15-25% by weight.

Preferably, in step (2), the liquid-to-solid ratio of the water to the pulverized material with a particle size of 20-200 mesh is 20-60 mL/g.

Preferably, in step (2), the stirring temperature is 50-70°C.

Preferably, in step (2), the stirring time is 5-12 hours.

Preferably, in step (3), the liquid-to-solid ratio of the organic solvent to the sieve oversize A is 10-60 mL/g.

Preferably, in step (3), the liquid-to-solid ratio of the organic solvent to the sieve oversize A is 20-40 mL/g.

Preferably, in step (3), the organic solvent is selected from one or more of methanol, ethanol, ethylene glycol, polyethylene glycol, glycerol, methyl acetate and ethyl acetate.

Preferably, in step (3), the stirring temperature is 60-80°C.

Preferably, in step (4), the drying temperature is 80-105° C., and the drying time is 4-16 h.

The method of the present invention can make full use of the glass fibers in the waste wind turbine blades, enrich the glass fibers in the wind turbine blades by simple and quick means, and recover materials with high glass fiber enrichment by combining crushing and stirring, thereby facilitating their subsequent recycling. The process has low energy consumption and is environmentally friendly.

Detailed ways

The specific embodiments of the present invention are described in detail below. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

The endpoints and any values of the ranges disclosed herein are not limited to the exact ranges or values, and these ranges or values should be understood to include values close to these ranges or values. For numerical ranges, the endpoint values of each range, the endpoint values of each range and the individual point values, and the individual point values can be combined with each other to obtain one or more new numerical values. Value ranges are intended to be considered specifically disclosed herein.

The present invention provides a method for enriching glass fibers in waste wind turbine blades, the method comprising the following steps:

In the present invention, the discarded wind turbine blades are blades that are retired from wind power plants or cannot be used due to accidents. The blades are mainly composed of a thermosetting composite material composed of glass fibers (the content of other substances is extremely small and can be ignored, and the properties are not much different from the main components). The glass fiber content in the discarded wind turbine blades is 50-85% by weight, and the resin content is 15-50% by weight.

In step (1), it is necessary to simultaneously control the proportion of the pulverized material with a particle size of >20 mesh to be 10-30 weight % and the proportion of the particle size of 20-200 mesh to be ≥20 weight %.

In a preferred embodiment, in step (1), the proportion of the pulverized material with a particle size of >20 mesh is controlled to be 15-25% by weight. The proportion of particle size >20 mesh in the material can be 15 weight %, 16 weight %, 17 weight %, 18 weight %, 19 weight %, 20 weight %, 21 weight %, 22 weight %, 23 weight %, 24 weight % or 25 weight %.

In step (2) of the present invention, the liquid-to-solid ratio of the water to the pulverized material with a particle size of 20-200 mesh is 20-60 mL/g, preferably 30-60 mL/g, specifically 30 mL/g, 35 mL/g, 40 mL/g, 45 mL/g, 50 mL/g, 55 mL/g or 60 mL/g.

Preferably, in step (2), the stirring temperature is 50-70° C. In a specific embodiment, in step (2), the stirring temperature can be 50° C., 55° C., 60° C., 65° C. or 70° C.

In a preferred embodiment, in step (2), the stirring time is 5-12 hours. In a specific embodiment, in step (2), the stirring time can be 5 hours, 6 hours, 7 hours, 8 hours, 9 hours, 10 hours, 11 hours or 12 hours.

In step (3) of the present invention, the liquid-to-solid ratio of the organic solvent to the sieve material A is 10-60 mL/g, preferably 20-40 mL/g, specifically 20 mL/g, 25 mL/g, 30 mL/g, 35 mL/g or 40 mL/g.

More preferably, in step (3), the stirring temperature is 60-80°C, and specifically can be 60°C, 65°C, 70°C, 75°C or 80°C.

In a specific embodiment, in step (3), the stirring time can be 2h, 3h, 4h, 5h, 6h, 7h or 8h.

In step (3) of the present invention, in order to avoid the subsequent organic components and crushed materials Therefore, in a preferred embodiment, after the stirring is completed, the mixture does not need to be cooled to room temperature, but is directly passed through an 80-mesh sieve immediately after the stirring is completed.

In a specific embodiment, in step (4), the liquid-to-solid ratio of the ethanol to the oversize material B can be 30 mL/g, 35 mL/g, 40 mL/g, 45 mL/g or 50 mL/g.

In a specific embodiment, in step (4), the stirring temperature can be 50°C, 55°C, 60°C, 65°C, 70°C, 75°C or 80°C, and the stirring time can be 2h, 3h, 4h, 5h, 6h or 7h.

Further preferably, in step (4), the drying temperature is 80-105°C, and the drying time is 4-16h. Specifically, the drying temperature can be 80°C, 85°C, 90°C, 95°C, 100°C or 105°C, and the drying time can be 4h, 7h, 10h, 13h or 16h.

The inventors obtained the above process conditions through a large number of experimental studies and full consideration of the differences in the degree of crushing of glass fibers and resins in the crushing stage, as well as the differences in the agglomeration of fibers and resins in the solution.

The method of the present invention can make full use of the glass fibers in the waste wind turbine blades, enrich the glass fibers in the wind turbine blades by simple and quick means, and recover materials with high glass fiber enrichment by combining overall crushing and stirring, which can facilitate their subsequent recycling. The process has low energy consumption and is environmentally friendly.

This method can greatly improve the applicable fields and application scope of the product by further enriching the fiber, increasing the glass fiber content of the product, and appropriately reducing the resin content, thereby achieving the purpose of low-cost resource utilization.

The present invention will be described in detail below by way of examples. It’s not just that.

The discarded wind turbine blades used in the following examples and comparative examples come from a domestic wind power plant, and the contents of glass fiber and resin are shown in Table 1.

Example 1

(1) crushing the discarded wind turbine blades as a whole to obtain crushed materials, and controlling the proportion of particles with a particle size of more than 20 mesh to be 21.3% by weight, and the proportion of particles with a particle size of 20-200 mesh to be 35.47% by weight, and then screening and collecting the crushed materials with a particle size of 20-200 mesh;

(2) mixing the collected pulverized material with a particle size of 20-200 mesh with water (the liquid-to-solid ratio of water to the pulverized material with a particle size of 20-200 mesh is 40 mL/g), stirring at 50° C. for 8 h, and then passing through a 140-mesh sieve to obtain an oversize material A;

(3) Mix the oversize A with methanol (the liquid-to-solid ratio of methanol to oversize A is 30 mL/g), then stir at 60° C. for 4 h, and then immediately pass through an 80-mesh sieve while hot to obtain oversize B;

(4) The oversize material B was mixed with ethanol at a liquid-to-solid ratio of ethanol to oversize material B of 40 mL/g, and then stirred at 60° C. for 5 h, followed by filtration, and the filtered solid was dried at 80° C. for 12 h.

Example 2

(1) crushing the discarded wind turbine blades as a whole to obtain crushed materials, and controlling the proportion of particles with a particle size of more than 20 mesh to be 18.9% by weight, and the proportion of particles with a particle size of 20-200 mesh to be 31.66% by weight, and then screening and collecting the crushed materials with a particle size of 20-200 mesh;

(2) mixing the collected pulverized material with a particle size of 20-200 mesh with water (the liquid-to-solid ratio of water to the pulverized material with a particle size of 20-200 mesh is 40 mL/g), stirring at 60° C. for 8 h, and then passing through a 140-mesh sieve to obtain an oversize material A;

(3) Mixing the oversize A with ethylene glycol (the liquid-to-solid ratio of ethylene glycol to oversize A is 30 mL/g), stirring at 70° C. for 4 h, and then immediately passing the mixture through an 80-mesh sieve while hot to obtain oversize B;

(4) The oversize material B was mixed with ethanol at a liquid-to-solid ratio of ethanol to oversize material B of 40 mL/g, and then stirred at 70° C. for 6 h, followed by filtration, and the filtered solid was dried at 80° C. for 10 h.

Example 3

(1) crushing the discarded wind turbine blades as a whole to obtain crushed materials, and controlling the proportion of particles with a particle size of more than 20 mesh to be 15.6% by weight, and the proportion of particles with a particle size of 20-200 mesh to be 36.76% by weight in the crushed materials, and then screening and collecting the crushed materials with a particle size of 20-200 mesh;

(2) mixing the collected pulverized material with a particle size of 20-200 mesh with water (the liquid-to-solid ratio of water to the pulverized material with a particle size of 20-200 mesh is 30 mL/g), stirring at 60° C. for 8 h, and then passing through a 140-mesh sieve to obtain an oversize material A;

(3) The oversize A was mixed with ethyl acetate (the liquid-to-solid ratio of ethyl acetate to the oversize A was 20 mL/g), and then stirred at 70° C. for 4 h, and then immediately passed through an 80-mesh sieve while hot to obtain an oversize B.

(4) Mix the sieve material B with ethanol, the liquid-to-solid ratio of ethanol to the sieve material B is 35 mL/g, then stir at 80°C for 6 h, filter, and dry the filtered solid at 80°C 8h.

Example 4

(1) crushing the discarded wind turbine blades as a whole to obtain crushed materials, and controlling the proportion of particles with a particle size of more than 20 mesh to be 22.4% by weight, and the proportion of particles with a particle size of 20-200 mesh to be 34.33% by weight, and then screening and collecting the crushed materials with a particle size of 20-200 mesh;

(2) mixing the collected pulverized material with a particle size of 20-200 mesh with water (the liquid-to-solid ratio of water to the pulverized material with a particle size of 20-200 mesh is 50 mL/g), stirring at 65° C. for 8 h, and then passing through a 140-mesh sieve to obtain an oversize material A;

(3) mixing the oversize A with ethylene glycol (the liquid-to-solid ratio of ethylene glycol to the oversize A is 40 mL/g), stirring at 60° C. for 6 h, and then immediately passing the oversize B through an 80-mesh sieve while hot to obtain an oversize B;

(4) The oversize material B was mixed with ethanol at a liquid-to-solid ratio of ethanol to oversize material B of 40 mL/g, and then stirred at 70° C. for 5 h, followed by filtration, and the filtered solid was dried at 100° C. for 4 h.

Comparative Example 1

The method of Example 1 is followed, except that in step (1), the proportion of particles with a particle size of >20 mesh in the crushed material is controlled to be 2.48% by weight, and the proportion of particles with a particle size of 20-200 mesh is controlled to be 41.22% by weight, and then screening is performed to collect the crushed material with a particle size of 20-200 mesh.

Comparative Example 2

The method of Example 1 is followed, except that in step (1), the proportion of particles with a particle size of >20 mesh in the crushed material is controlled to be 43.86% by weight, and the proportion of particles with a particle size of 20-200 mesh is controlled to be 22.43% by weight, and then screening is performed to collect the crushed material with a particle size of 20-200 mesh.

Comparative Example 3

(1) crushing the discarded wind turbine blades as a whole to obtain crushed materials, and controlling the proportion of particles with a particle size of more than 20 mesh to be 21.3% by weight, and the proportion of particles with a particle size of 20-200 mesh to be 26.26% by weight, and then screening and collecting the crushed materials with a particle size of 20-200 mesh;

(2) The collected pulverized material with a particle size of 20-200 mesh was mixed with water (the liquid-to-solid ratio of water to the pulverized material with a particle size of 20-200 mesh was 40 mL/g), and then stirred at 50° C. for 8 h, and then passed through a 140-mesh sieve to obtain an oversize material A, which was directly dried at 80° C. for 12 h.

Test Example 1

The content of glass fiber in the products obtained in Examples 1-4 and Comparative Examples 1-3 was detected respectively.

The method for detecting the content of glass fiber is: accurately weigh the sample weight M1, and after calcining at 600°C for 3 hours, weigh the weight M2. The content of glass fiber is R=M2/M1*100%.

The results are shown in Table 1.

Table 1

It can be seen from the results in Table 1 that after rapid enrichment by this method, the glass fiber content in the obtained product is already above 85%, which is very high and can be directly used in the fields of building materials and the like.

The preferred embodiments of the present invention are described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications, including the combination of various technical features in any other suitable manner, and these simple modifications and combinations should also be regarded as the contents disclosed by the present invention and belong to the protection scope of the present invention.

Claims

A method for enriching glass fibers in waste wind turbine blades, characterized in that the method comprises the following steps:

(1) crushing the discarded wind turbine blades to obtain crushed materials, and controlling the proportion of particles with a particle size of more than 20 mesh in the crushed materials to be 15-25% by weight, and the proportion of particles with a particle size of 20-200 mesh to be ≥20% by weight, and then screening and collecting the crushed materials with a particle size of 20-200 mesh;

(2) mixing the collected pulverized material with a particle size of 20-200 mesh with water, stirring at 40-80° C. for 2-16 hours, and then passing through a 140-mesh sieve to obtain an oversize material A;

(3) mixing the oversize A with an organic solvent, stirring at 40-80° C. for 2-8 hours, and then passing through an 80-mesh sieve to obtain an oversize B;

(4) Mix the sieve material B with ethanol, wherein the liquid-to-solid ratio of the ethanol to the sieve material B is 30-50 mL/g, and then stir at 50-80° C. for 2-7 h, followed by filtering, and drying the filtered solid at 60-150° C. for 2-24 h.
The method according to claim 1 is characterized in that in step (2), the liquid-to-solid ratio of the water to the crushed material with a particle size of 20-200 mesh is 20-60 mL/g.
The method according to claim 1, characterized in that in step (2), the stirring temperature is 50-70°C.
The method according to claim 1 or 3, characterized in that, in step (2), the stirring time is 5-12 hours.
The method according to claim 1, characterized in that in step (3), the liquid-to-solid ratio of the organic solvent to the sieve oversize A is 10-60 mL/g.
The method according to claim 1, characterized in that in step (3), the liquid-to-solid ratio of the organic solvent to the sieve oversize A is 20-40 mL/g.
The method according to claim 1 or 5, characterized in that in step (3), the organic solvent is selected from one or more of methanol, ethanol, ethylene glycol, polyethylene glycol, glycerol, methyl acetate and ethyl acetate.
The method according to claim 1, characterized in that in step (3), the stirring temperature is 60-80°C.
The method according to claim 1 is characterized in that, in step (4), the drying temperature is 80-105°C and the drying time is 4-16h.