Waste wind power blade crushing and grinding process

Abstract

The invention relates to the technical field of wind power blade recovery, and discloses a waste wind power blade crushing and grinding process which comprises the following steps: cutting / segmenting a waste wind power blade to obtain small blocks suitable for subsequent treatment; the cut materials are fed into coarse crushing equipment to be subjected to coarse crushing, and large particles are obtained; feeding the coarsely crushed material into fine crushing equipment for further crushing to obtain smaller particles; metal impurities in the materials are removed through high-intensity magnetic separation equipment; and the crushed materials are classified and screened through screening equipment. By adopting a comprehensive treatment process scheme comprising a plurality of links of cutting, segmentation, coarse crushing, fine crushing, screening, iron removal, grinding and the like, the technical effect of remarkably improving the treatment efficiency of the waste wind power blade is achieved. Compared with a single crushing or grinding technical scheme which is mostly adopted in the prior art, through a multi-stage treatment process, the effects of all equipment are fully exerted, and the burden of each link is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of wind turbine blade recycling, and in particular to a process for crushing and grinding waste wind turbine blades. Background Art

[0002] Wind turbine blades are usually made of composite materials (such as glass fiber, carbon fiber, resin, etc.), which have excellent mechanical properties and corrosion resistance. Therefore, wind turbine blades can withstand the test of extreme weather and strong winds during use. However, it is precisely because of the special properties of these materials that the recycling of discarded wind turbine blades has become very difficult. Traditional waste disposal methods, such as incineration or landfill, not only cannot efficiently recycle useful materials in wind turbine blades, but may also cause secondary pollution to the environment. Therefore, how to effectively recycle and utilize the materials of waste wind turbine blades, especially how to process the discarded wind turbine blades into powder for further use, has become a technical problem that needs to be solved urgently.

[0003] The treatment of waste wind turbine blades mainly relies on mechanical crushing and chemical treatment. Mechanical crushing usually uses a single crushing equipment for processing, such as a single-shaft shredder, a hammer crusher, etc. Although these devices can crush wind turbine blades into smaller particles, due to the complexity and hardness of wind turbine blade materials, single crushing equipment often cannot effectively crush them into fine particles. The crushing efficiency is low and it is difficult to control the particle size, resulting in some larger particles not being fully processed, affecting the effect of subsequent processing.

[0004] In addition, the screening process in the existing technology also has some shortcomings. Most processing processes use a single screening device to classify the crushed materials, but a single screening device is often difficult to achieve efficient particle size control and it is difficult to ensure the particle size uniformity of the product in large-scale production. The mixing of different granular materials not only increases the difficulty of subsequent processing, but also reduces the recovery rate of powder. Summary of the invention

[0005] In view of the shortcomings of the prior art, the present invention provides a process for crushing and grinding waste wind turbine blades, which solves the problem that due to the complexity and hardness of wind turbine blade materials, a single crushing equipment often cannot effectively crush them into fine particles, the crushing efficiency is low, and the particle size is difficult to control.

[0006] To achieve the above objectives, the present invention is implemented through the following technical solutions: A waste wind turbine blade crushing and grinding process, comprising the following steps:

[0007] Cutting / splitting the waste wind turbine blades to obtain small pieces suitable for subsequent processing;

[0008] The cut materials are sent to the coarse crushing equipment for coarse crushing to obtain larger particles;

[0009] The coarsely crushed material is sent to the fine crushing equipment for further crushing to obtain smaller particles;

[0010] Use strong magnetic separation equipment to remove metal impurities in the material;

[0011] The crushed materials are graded and screened through screening equipment;

[0012] The screened materials are sent to the grinding mill for pulverization;

[0013] Separate fine powder from larger particles through secondary screening equipment;

[0014] The fine powder is stored and the larger particles are sent back to the mill through the return system for further grinding.

[0015] Preferably, the cutting and trimming steps are performed by a mechanical cutting machine, a laser cutting machine or a water jet cutting machine, wherein:

[0016] The mechanical cutter cuts the waste wind turbine blades with a high-speed rotating blade at a speed of 50 to 100 mm per minute;

[0017] The laser cutting machine uses a focused laser beam to precisely cut the blades. The laser power is 500W to 2kW and the cutting accuracy is ±0.5mm.

[0018] The water jet cutting machine uses high-pressure water jet for cutting, with a water pressure of 2500 to 4000 bar, and is suitable for processing wind turbine blades with complex shapes.

[0019] Preferably, the coarse crushing device is a double-shaft shredder, and the fine crushing device is a double-shaft shredder or a hammer mill, wherein:

[0020] The double-shaft shredder’s cutter is designed with a multi-tooth blade made of high-strength alloy. The shear force generated by the synchronously rotating double shafts tears the waste wind turbine blades into larger particles. The rotation speed is 60-80RPM, and the cutter gap is 5-10cm.

[0021] The hammer mill uses a high-hardness alloy hammer head to strike the material through the high-speed rotating hammer head. The degree of material crushing is adjustable and it is suitable for refining particles to the millimeter level.

[0022] Preferably, the screening equipment is a vibrating screen, a rotary screen or a drum screen, and the screen aperture is set to multiple levels, namely 20 mm, 5 mm and 1 mm, and the screening process includes the following characteristics:

[0023] The vibrating screen separates the particles through the screen by high-frequency vibration, the vibration frequency is 50 to 100 times per minute, and the screen material is wear-resistant steel mesh;

[0024] The rotary screen uses a circular screen, which improves the passing efficiency of materials through the rotating action, and the screening effect is more uniform;

[0025] The drum screen is suitable for processing larger particles. The screen is made of metal mesh or stainless steel mesh and rotates at a speed of 30 to 40 RPM.

[0026] Preferably, the mill is a jet mill or a roller mill, and the mill is equipped with a water cooling system, wherein:

[0027] The airflow mill uses high-speed airflow to create collision and friction between the material and the grinding disc, and can achieve efficient grinding at low temperatures. It is suitable for crushing high-strength composite materials. The feed particle size is 5mm and the output particle size is 10-50 microns.

[0028] The roller mill uses rolling to press the material, which can efficiently crush hard materials. The output particle size is adjustable and it is suitable for large-scale production.

[0029] Preferably, the feed particle size of the airflow mill is 5 mm, the grinding pressure is 30-50 kN, the airflow velocity is 200-300 m / s, and the airflow mill is equipped with a water cooling system with a water temperature of 5-10°C to ensure that the temperature of the powder does not exceed 50°C to avoid material adhesion problems caused by overheating.

[0030] Preferably, the strong magnetic separation equipment is a permanent magnetic separator or an electromagnetic separator, and the magnetic field strength is set to 800-1200 Gauss, wherein:

[0031] Permanent magnetic separators are suitable for materials with less metal impurities and can effectively remove iron materials through permanent magnets;

[0032] Electromagnetic separators are suitable for materials with high metal impurity content. They can efficiently separate metal impurities by generating strong magnetic force through electromagnetic fields.

[0033] Preferably, the return material system is an automated conveying system, and the system comprises:

[0034] Belt conveyors, screw conveyors or pneumatic conveying systems are used to return incompletely ground particles to the mill for secondary grinding;

[0035] The system also includes an automated control system that can automatically adjust the amount of returned material according to the material particle size and degree of crushing to ensure grinding efficiency.

[0036] Preferably, the secondary screening equipment is a high-efficiency vibrating screen with a screen aperture of 0.5 mm, which is used to separate fine powder from incompletely crushed particles, wherein:

[0037] The amplitude and frequency of the vibrating screen can be adjusted according to the material characteristics to ensure the best grading effect of the material;

[0038] The screen material is made of wear-resistant metal mesh, which can operate stably for a long time and ensure the screening accuracy.

[0039] Preferably, the storage step is performed in a storage bin, and the storage bin is equipped with a temperature control device to ensure the stability of the quality of the powder during storage, and the temperature control device includes:

[0040] Temperature sensors, heaters and coolers are used to maintain the temperature inside the storage silo between 10 and 25°C to prevent moisture and temperature fluctuations from causing powder agglomeration or deterioration.

[0041] The present invention provides a process for crushing and grinding waste wind turbine blades. It has the following beneficial effects:

[0042] 1. The present invention achieves the technical effect of significantly improving the treatment efficiency of waste wind turbine blades by adopting a comprehensive treatment process scheme including cutting, segmentation, coarse crushing, fine crushing, screening, iron removal, grinding and other links. Compared with the prior art that mostly adopts a single crushing or grinding technical scheme, the present invention uses a multi-stage treatment process to give full play to the role of each device, reduce the burden of each link, optimize the particle size distribution of the material, and ensure the efficient separation and full utilization of the waste.

[0043] 2. The present invention introduces intelligent control, temperature control system, automatic material return and other technical means into the process, which effectively reduces energy consumption and improves the stability of equipment operation. Compared with the problems of equipment overload operation and energy waste that may exist in the prior art, the present invention reduces the thermal damage of materials and equipment wear during the processing process by optimizing the processing flow and accurately controlling the temperature of the mill and the equipment load, thereby improving the service life of the equipment and the stability of long-term operation.

[0044] 3. The present invention ensures the uniformity and purity of the powder through multi-stage screening, precision grinding and iron removal technology, achieving the technical effect of improving the quality of the powder. Compared with the technical solutions in the prior art that may cause uneven particle size or ineffective removal of metal impurities, the present invention can more accurately separate materials of different particle sizes and remove impurities through multiple screening and an efficient iron removal system, ensuring the smooth progress of subsequent processing links. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 is a flow chart of the method of the present invention;

[0046] Figure 2 It is a schematic diagram of the overall framework of the present invention. DETAILED DESCRIPTION

[0047] The following will be combined with the drawings in the specification of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0048] Please refer to the attached Figure 1 - Attachment Figure 2 The embodiment of the present invention provides a waste wind turbine blade crushing and grinding process, comprising the following steps:

[0049] Cutting / splitting the waste wind turbine blades to obtain small pieces suitable for subsequent processing;

[0050] The cut materials are sent to the coarse crushing equipment for coarse crushing to obtain larger particles;

[0051] The coarsely crushed material is sent to the fine crushing equipment for further crushing to obtain smaller particles;

[0052] Use strong magnetic separation equipment to remove metal impurities in the material;

[0053] The crushed materials are graded and screened through screening equipment;

[0054] The screened materials are sent to the grinding mill for pulverization;

[0055] Separate fine powder from larger particles through secondary screening equipment;

[0056] The fine powder is stored and the larger particles are sent back to the mill through the return system for further grinding.

[0057] Specifically, the waste wind turbine blades are cut or split into small pieces suitable for subsequent processing, and then these small pieces are sent to the coarse crushing equipment for coarse crushing to obtain larger particles, and then the coarsely crushed materials are sent to the fine crushing equipment for further crushing to obtain smaller particles, and then the strong magnetic separation equipment is used to remove metal impurities in the materials to ensure the equipment safety and powder purity in subsequent processing. Next, the materials are graded and screened by screening equipment, and the materials are separated according to particle size to ensure the collection of fine powder and the removal of coarse particles. The screened materials are then sent to the grinding mill for further crushing to obtain finer powder, and then the fine powder is separated from larger particles by secondary screening equipment, the fine powder is stored, and the larger particles are sent back to the grinding mill through the return system for further grinding. The entire process flow greatly improves the recovery rate and powder quality of waste wind turbine blades through the optimization and combination of each link, and at the same time solves the problems of incomplete crushing, uneven particle size, and incomplete removal of metal impurities in traditional technologies, thereby realizing efficient and environmentally friendly recycling and reuse of waste wind turbine blades.

[0058] The cutting and trimming steps are performed by a mechanical cutting machine, a laser cutting machine or a water jet cutting machine, wherein:

[0059] The mechanical cutter cuts the waste wind turbine blades with a high-speed rotating blade at a speed of 50 to 100 mm per minute;

[0060] The laser cutting machine uses a focused laser beam to precisely cut the blades. The laser power is 500W to 2kW and the cutting accuracy is ±0.5mm.

[0061] The water jet cutting machine uses high-pressure water jet for cutting, with a water pressure of 2500 to 4000 bar, and is suitable for processing wind turbine blades with complex shapes.

[0062] Specifically, mechanical cutting machines use high-speed rotating blades to cut waste wind turbine blades at a cutting speed of 50-100 mm per minute. This method can quickly and efficiently cut wind turbine blades into small pieces suitable for subsequent processing, but may face the challenge of uneven cutting when processing thicker or harder materials; laser cutting machines use focused laser beams to accurately cut blades. The laser power range is 500W~2kW, and the cutting accuracy is ±0.5mm. It can achieve high-precision cutting and is especially suitable for applications with high cutting accuracy requirements. It can reduce thermal damage during the cutting process and avoid material deformation, but its equipment cost is high and its scope of application is relatively limited; water jet cutting machines use high-pressure water jets to cut blades. Cutting, the water pressure is 2500-4000bar, which is suitable for processing wind turbine blades with complex shapes and thicker materials. The advantage of water jet cutting technology is that it can efficiently process wind turbine blades with complex shapes and hard materials without causing thermal effects, thus avoiding the problem of thermal deformation in traditional cutting methods. However, since a large amount of water and high energy consumption are required during the water jet cutting process, its use cost is relatively high, and more subsequent treatments may be required to remove water stains. Through the combined application of multiple cutting technologies, the present invention can select the best cutting method according to the different characteristics of waste wind turbine blades, ensuring the cutting effect while taking into account processing efficiency and economy, thereby providing an ideal material basis for subsequent crushing and grinding steps.

[0063] The coarse crushing equipment is a double-shaft shredder, and the fine crushing equipment is a double-shaft shredder or a hammer mill, wherein:

[0064] The double-shaft shredder’s cutter is designed with a multi-tooth blade made of high-strength alloy. The shear force generated by the synchronously rotating double shafts tears the waste wind turbine blades into larger particles. The rotation speed is 60-80RPM, and the cutter gap is 5-10cm.

[0065] The hammer mill uses a high-hardness alloy hammer head to strike the material through the high-speed rotating hammer head. The degree of material crushing is adjustable and it is suitable for refining particles to the millimeter level.

[0066] Specifically, the shear force generated by the synchronously rotating double shafts is used to tear the waste wind turbine blades into larger particles. The rotation speed is usually 60-80RPM, and the tool gap is 5-10cm. This design can efficiently carry out preliminary processing of larger waste wind turbine blades, and use the shear force generated by the relative movement between the double shafts to tear the materials into larger particles. At the same time, the high-strength alloy tool ensures the durability and long service life of the equipment. However, due to the large force generated during the shearing process, it is easy to cause certain deformation to the material. Therefore, it is suitable for coarse crushing of the material to prepare for subsequent fine crushing. The choice of fine crushing equipment is a double-shaft shredder or a hammer mill. Among them, the double-shaft shredder can also be used during the fine crushing process. The synchronously rotating double shafts tear the material into smaller particles with higher precision, but its applicability and production efficiency are usually lower than those of a hammer mill, and it is mainly suitable for material processing that requires finer particles; the hammer mill uses a high-hardness alloy hammer head, and the high-speed rotating hammer head strikes the material to break and refine the material. The degree of material crushing is adjustable, and it is suitable for refining the material to the millimeter level, which can effectively improve the processing accuracy and crushing efficiency of the material. Especially when processing hard composite materials such as wind turbine blades, the hammer mill has stronger adaptability, but it also needs to control the heat generated during the crushing process to avoid excessive temperature affecting the material properties. Therefore, in actual applications, a temperature control system is usually used to reduce the thermal effect to ensure the stability of the equipment and the crushing effect. The reasonable combination of the two enables the present invention to achieve efficient material processing in the crushing process of waste wind turbine blades, which not only ensures the processing of larger particles, but also achieves the goal of fine granulation, meeting the requirements of subsequent screening and grinding processes.

[0067] The screening equipment is a vibrating screen, a rotary screen or a drum screen, and the screen aperture is set to multiple levels, namely 20 mm, 5 mm and 1 mm. The screening process includes the following features:

[0068] The vibrating screen separates the particles through the screen by high-frequency vibration, the vibration frequency is 50 to 100 times per minute, and the screen material is wear-resistant steel mesh;

[0069] The rotary screen uses a circular screen, which improves the passing efficiency of materials through the rotating action, and the screening effect is more uniform;

[0070] The drum screen is suitable for processing larger particles. The screen is made of metal mesh or stainless steel mesh and rotates at a speed of 30 to 40 RPM.

[0071] Specifically, the vibrating screen separates particles through the screen through high-frequency vibration, with a vibration frequency of 50 to 100 times per minute. The screen is made of wear-resistant steel mesh, and the high-frequency vibration can quickly pass the material through the screen. At the same time, the high-frequency vibration allows the material particles to fully move on the screen surface, thereby effectively separating particles of different sizes. The screen is made of wear-resistant steel mesh to ensure durability and wear resistance during the screening process, and is suitable for large-scale, high-intensity material screening processing; the rotary screen uses a circular screen to improve the material passing efficiency through the rotating action, and the screening effect is more uniform. The advantage of the rotary screen is that its unique rotating mechanism can make the material produce a strong dynamic force on the screen surface, increase the contact area between the particles and the screen, and thereby improve the screening efficiency and screening accuracy, especially when processing more complex types of materials, its separation effect It is relatively stable and can ensure a relatively uniform particle size distribution. It is suitable for processing waste wind turbine blade materials of different types and sizes. The drum screen is suitable for processing larger particles. The screen is composed of a metal mesh or a stainless steel mesh, and the rotation speed is 30-40RPM. The drum screen makes the material tumble continuously by rotating the cylinder, and the material particles are gradually separated from the screen by gravity and friction. It is suitable for processing larger particles. The screen material is made of a metal mesh or a stainless steel mesh, which not only has strong pressure resistance and wear resistance, but also can withstand a large load, ensuring long-term stable operation. The rotation speed is set to 30-40RPM to meet the processing requirements of different materials. By adjusting the rotation speed, the screening efficiency and material processing capacity can be effectively controlled, ensuring the smooth separation of larger particles, and finally making the screening process achieve the best effect in the processing of materials of different particle sizes. Through the cooperation of a variety of screening equipment, the present invention can select the most suitable screening method according to the different characteristics of the material, ensure that the screening effect of each stage is accurate and efficient, and provide an ideal material distribution basis for the subsequent grinding and recycling process.

[0072] The grinding mill is a jet mill or a roller mill, and the grinding mill is equipped with a water cooling system, wherein:

[0073] The airflow mill uses high-speed airflow to create collision and friction between the material and the grinding disc, and can achieve efficient grinding at low temperatures. It is suitable for crushing high-strength composite materials. The feed particle size is 5mm and the output particle size is 10-50 microns.

[0074] The roller mill uses rolling to press the material, which can efficiently crush hard materials. The output particle size is adjustable and it is suitable for large-scale production.

[0075] Specifically, the air flow mill uses high-speed airflow to create collision and friction between the material and the grinding disc, and can achieve efficient grinding at low temperatures. It is suitable for crushing high-strength composite materials. The working principle of the air flow mill is based on the strong impact force generated by the high-speed airflow, which causes the material particles to violently collide and rub against the grinding disc in a short period of time, thereby crushing the material to the micron level. It is especially suitable for the processing of hard composite materials such as wind turbine blades. It can be ground in a low-temperature environment, effectively avoiding the adhesion and deformation of the material due to excessive temperature, ensuring the quality of the powder and the stability of the equipment. The feed particle size is usually 5mm and the output particle size is 10-50 microns. By adjusting the air flow speed, pressure and grinding disc gap, the powder size can be precisely controlled to meet the powder requirements of different particle size requirements; the roller mill uses rolling to press the material, and the high pressure between two or more rollers presses the material Crushing, with high crushing efficiency, especially suitable for crushing harder materials, roller mill can crush materials efficiently in a short time, and less excessive heat is generated during the crushing process. Compared with other types of grinding equipment, its energy consumption is lower, suitable for large-scale production needs, and the discharge particle size is adjustable. The size of the final particles can usually be controlled by adjusting the gap between the rollers or the pressing pressure. It is suitable for large-scale material processing. In the crushing process of waste wind turbine blades, it can efficiently process materials, reduce energy consumption and improve production efficiency. The mill is also equipped with a water cooling system, which uses a water cooling device to take away the heat generated by the material during the grinding process in time, avoiding problems such as material adhesion, equipment failure or reduced production efficiency caused by overheating, ensuring the stability and continuity of the entire grinding process, and the water cooling system also effectively extends the service life of the equipment and improves the reliability of the overall process. Through the reasonable selection and matching of airflow mills and roller mills.

[0076] The feed particle size of the air flow mill is 5 mm, the grinding pressure is 30-50 kN, the air flow velocity is 200-300 m / s, and the air flow mill is equipped with a water cooling system with a water temperature of 5-10°C to ensure that the temperature of the powder does not exceed 50°C to avoid material adhesion problems caused by overheating.

[0077] Specifically, the material particles are accelerated to an extremely high speed by high-speed airflow. Driven by the airflow, the material particles produce strong collision and friction with the grinding disc and other particles in the grinding chamber, thereby achieving efficient crushing of the material. This grinding method can crush the material into micron-level powder in a short time, which is suitable for the processing of high-hardness and high-strength composite materials. The feed particle size is controlled within 5mm, ensuring that the material has reached a suitable particle size before entering the grinding mill to reduce the load of the grinding mill and improve the grinding efficiency. The grinding pressure is set in the range of 30-50kN to provide sufficient crushing force while avoiding equipment loss caused by excessive pressure. The air flow speed is set between 200-300m / s. By adjusting the air flow speed, the crushing requirements of different materials can be met to ensure uniform particle size and stable quality of the powder. In addition, in order to solve the heat problem generated by high-speed collision during the grinding process, the air flow mill is equipped with an efficient water cooling system. The circulating cooling water keeps the temperature in the grinding chamber within an appropriate range. The water temperature is usually controlled at 5-10°C to quickly take away the heat generated during the operation of the equipment and ensure that the temperature of the powder does not exceed 50°C, thereby avoiding the material adhesion caused by excessive temperature. The water cooling system can not only effectively control the grinding temperature, but also reduce equipment wear, improve the operating stability and service life of the equipment, through the reasonable design of the air flow mill and the coordinated use of the water cooling system.

[0078] The strong magnetic separation equipment is a permanent magnetic separator or an electromagnetic separator, and the magnetic field strength is set to 800-1200 Gauss, wherein:

[0079] Permanent magnetic separators are suitable for materials with less metal impurities and can effectively remove iron materials through permanent magnets;

[0080] Electromagnetic separators are suitable for materials with high metal impurity content. They can efficiently separate metal impurities by generating strong magnetic force through electromagnetic fields.

[0081] Specifically, the permanent magnetic separator is suitable for materials with less metal impurities. It can effectively remove iron impurities from the materials by using the magnetic field of the permanent magnet. It has the advantages of simple structure, stable operation, and low maintenance cost. It is especially suitable for processing waste wind turbine blades or other solid wastes with low metal impurity content. When removing iron materials, the permanent magnetic separator can maintain a high sorting efficiency, while avoiding the problem of excessive energy consumption that may occur when the traditional electromagnetic separator is processing low-magnetic materials; while the electromagnetic separator is suitable for materials with high metal impurity content. The electromagnetic separator generates a strong magnetic force through the electromagnetic field, which can efficiently separate the metal impurities during the sorting process. The intensity and operating frequency of the electromagnetic field can be adjusted according to the characteristics of the material, thereby realizing efficient separation of different metal impurities. Especially when processing composite materials such as waste wind turbine blades, the electromagnetic separator can quickly separate iron-containing and other metal substances from non-metallic components, avoiding the problems of incomplete sorting and impurity residue when traditional magnetic separation equipment processes high-impurity materials, and further improving the purity and efficiency of subsequent processing. The combined use of the two can select the most suitable sorting equipment according to the metal impurity content of the material, ensuring the magnetic separation effect in the entire processing process, and effectively improving the resource utilization rate of waste wind turbine blades, reducing the impurity pollution that may occur in subsequent processing links, thereby providing a cleaner raw material basis for the final utilization of the material.

[0082] The return material system is an automated conveying system, and the system comprises:

[0083] Belt conveyors, screw conveyors or pneumatic conveying systems are used to return incompletely ground particles to the mill for secondary grinding;

[0084] The system also includes an automatic control system that can automatically adjust the amount of returned material according to the material particle size and degree of crushing to ensure grinding efficiency.

[0085] Specifically, belt conveyors are suitable for dry materials with large particles and good fluidity, which can ensure the smooth transmission of materials and have a low system failure rate; screw conveyors show strong advantages when handling wet or sticky materials, avoiding blockage or accumulation of materials during transmission, and have strong adaptability; and pneumatic conveying systems use air power to quickly and evenly transport materials to designated locations, which is especially suitable for the recovery of fine powder or light materials, has a good dust control effect, reduces factory environmental pollution, and improves work efficiency. The automated control system can monitor the particle size and grinding conditions of the material in real time by installing sensors, monitoring instruments and regulators. The system can automatically adjust the amount of return material according to different material conditions to avoid excessive return material causing the mill to be overloaded, and to avoid the material being sent back before reaching the ideal particle size, thereby improving the accuracy and efficiency of material crushing. Through this intelligent and automated material return mechanism, the entire material handling process is not only more efficient and energy-saving, but also can effectively reduce errors in human operations, improve the degree of automation in the production process and the consistency of material handling, thereby further improving the overall operating efficiency and product quality of the waste wind turbine blade crushing and grinding process.

[0086] The secondary screening equipment is a high-efficiency vibrating screen with a screen aperture of 0.5 mm, which is used to separate fine powder from incompletely crushed particles, wherein:

[0087] The amplitude and frequency of the vibrating screen can be adjusted according to the material characteristics to ensure the best grading effect of the material;

[0088] The screen material is made of wear-resistant metal mesh, which can operate stably for a long time and ensure the screening accuracy.

[0089] The storage step is carried out in a storage bin, and the storage bin is equipped with a temperature control device to ensure the stability of the powder quality during storage. The temperature control device includes:

[0090] Temperature sensors, heaters and coolers are used to maintain the temperature inside the storage silo between 10 and 25°C to prevent moisture and temperature fluctuations from causing powder agglomeration or deterioration.

[0091] Specifically, the amplitude and frequency of the vibrating screen can be adjusted according to the characteristics of the material to ensure the best grading effect of the material. The vibrating screen realizes efficient grading of particles through the vibration principle. The material undergoes vibrating motion on the screen surface, so that particles of different sizes can be quickly separated. The amplitude and frequency can be flexibly adjusted according to the characteristics of the material such as humidity, particle size and adhesion, so as to obtain an ideal grading effect. This adjustability greatly improves the adaptability and processing efficiency of the equipment, and can accurately separate fine powder and larger particles, ensuring the consistency of powder quality in subsequent processing. The screen material adopts wear-resistant metal mesh, which can operate stably for a long time and ensure screening accuracy. The metal mesh has high wear resistance and can withstand large mechanical friction and material impact. It is not easy to be damaged or deformed during long-term use, ensuring screening accuracy and work efficiency. Especially when processing waste wind turbine blades with high strength and hardness, the wear-resistant metal mesh can effectively extend the service life of the screening equipment, reduce maintenance frequency and maintenance costs, thereby improving the stability and economy of the entire processing process. The storage step is carried out through a storage bin, and the storage bin is equipped with a temperature control device to ensure the stability of the quality of the powder during storage. The temperature control device includes a temperature sensor, a heater and a cooler to maintain the temperature inside the storage bin between 10 and 25°C to prevent moisture and temperature fluctuations from causing powder agglomeration or deterioration. The temperature control system ensures the stability of the internal environment of the storage bin by real-time monitoring the temperature in the bin and automatically adjusting the heating or cooling function, thereby avoiding powder agglomeration, powder quality deterioration or adhesion problems caused by environmental factors such as moisture or temperature changes. The temperature sensor can accurately monitor the temperature in the bin to ensure that the temperature during storage is always maintained within an appropriate range. The heater and cooler adjust the temperature according to actual needs to keep the environment inside the storage bin at a constant temperature to meet storage needs under various weather conditions. Through these control measures, the quality of the powder material is effectively prevented from changing, ensuring that the powder maintains high quality and consistency during subsequent processing or use.

[0092] The optimization of the pulverizing efficiency directly affects the material processing speed and energy consumption. In the jet mill of the present invention, the pulverizing efficiency can be described by the following formula:

[0093]

[0094] Among them, η is the crushing efficiency, P f is the mass of powder crushed per unit time, P m The invention significantly improves the grinding efficiency by optimizing the grinding pressure, air flow velocity and temperature control of the air flow mill. Compared with the traditional grinding equipment, it can significantly reduce energy consumption and improve the grinding capacity per unit time.

[0095] In the secondary screening device of the present invention, the accuracy of the particle size distribution determines the quality stability and availability of the final product. The classification accuracy can be described by the screening accuracy index (CI), which is related to the vibration frequency of the screening device, the mesh aperture and the material properties. The specific formula is as follows:

[0096]

[0097] Where CI is the particle classification accuracy, d i is the size of the ith particle, d0 is the desired target particle size, and n is the number of particles in the particle size distribution. By adjusting the amplitude, frequency and mesh aperture of the vibrating screen, the present invention can achieve higher particle classification accuracy, make the distribution of powder particle size more uniform, and effectively improve the recyclability of the material and the efficiency of subsequent processing.

[0098] In order to further improve the energy utilization rate of the entire waste wind turbine blade crushing and grinding process, the optimization of the return system and the automatic control system of the present invention improves the overall energy efficiency ratio of the equipment. The energy efficiency ratio (ER) reflects the material processing capacity that can be achieved per unit energy input. The specific calculation formula is as follows:

[0099]

[0100] Among them, ER is energy efficiency ratio, M output is the mass of material processed per unit time, P input The invention can accurately adjust the return material amount and grinding intensity by the automatic control system according to the input energy power, effectively reduce the overall energy consumption of the system, increase the material processing capacity per unit input power, and reduce unnecessary energy waste.

[0101] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A process for crushing and grinding waste wind turbine blades, characterized in that: The following steps are involved: Cutting / splitting the waste wind turbine blades to obtain small pieces suitable for subsequent processing; The cut materials are sent to the coarse crushing equipment for coarse crushing to obtain larger particles; The coarsely crushed material is sent to the fine crushing equipment for further crushing to obtain smaller particles; Use strong magnetic separation equipment to remove metal impurities in the material; The crushed materials are graded and screened through screening equipment; The screened materials are sent to the grinding mill for pulverization; Separate fine powder from larger particles through secondary screening equipment; The fine powder is stored and the larger particles are sent back to the mill through the return system for further grinding.

2. The process for crushing and grinding waste wind turbine blades according to claim 1, characterized in that: The cutting and trimming steps are performed by a mechanical cutting machine, a laser cutting machine or a water jet cutting machine, wherein: The mechanical cutter cuts the waste wind turbine blades with a high-speed rotating blade at a speed of 50 to 100 mm per minute; The laser cutting machine uses a focused laser beam to precisely cut the blades. The laser power is 500W to 2kW and the cutting accuracy is ±0.5mm. The water jet cutting machine uses high-pressure water jet for cutting, with a water pressure of 2500 to 4000 bar, and is suitable for processing wind turbine blades with complex shapes.

3. The process for crushing and grinding waste wind turbine blades according to claim 1, characterized in that: The coarse crushing equipment is a double-shaft shredder, and the fine crushing equipment is a double-shaft shredder or a hammer mill, wherein: The double-shaft shredder’s cutter is designed with a multi-tooth blade made of high-strength alloy. The shear force generated by the synchronously rotating double shafts tears the waste wind turbine blades into larger particles. The rotation speed is 60-80RPM, and the cutter gap is 5-10cm. The hammer mill uses a high-hardness alloy hammer head to strike the material through the high-speed rotating hammer head. The degree of material crushing is adjustable and it is suitable for refining particles to the millimeter level.

4. The process for crushing and grinding waste wind turbine blades according to claim 1, characterized in that: The screening equipment is a vibrating screen, a rotary screen or a drum screen, and the screen aperture is set to multiple levels, namely 20 mm, 5 mm and 1 mm. The screening process includes the following features: The vibrating screen separates the particles through the screen by high-frequency vibration, the vibration frequency is 50 to 100 times per minute, and the screen material is wear-resistant steel mesh; The rotary screen uses a circular screen, which improves the passing efficiency of materials through the rotating action, and the screening effect is more uniform; The drum screen is suitable for processing larger particles. The screen is made of metal mesh or stainless steel mesh and rotates at a speed of 30 to 40 RPM.

5. The process for crushing and grinding waste wind turbine blades according to claim 1, characterized in that: The grinding mill is a jet mill or a roller mill, and the grinding mill is equipped with a water cooling system, wherein: The airflow mill uses high-speed airflow to create collision and friction between the material and the grinding disc, and can achieve efficient grinding at low temperatures. It is suitable for crushing high-strength composite materials. The feed particle size is 5mm and the output particle size is 10-50 microns. The roller mill uses rolling to press the material, which can efficiently crush hard materials. The output particle size is adjustable and it is suitable for large-scale production.

6. The waste wind turbine blade crushing and grinding process according to claim 1 is characterized in that: The feed particle size of the air flow mill is 5 mm, the grinding pressure is 30-50 kN, the air flow velocity is 200-300 m / s, and the air flow mill is equipped with a water cooling system with a water temperature of 5-10°C to ensure that the temperature of the powder does not exceed 50°C to avoid material adhesion problems caused by overheating.

7. The process for crushing and grinding waste wind turbine blades according to claim 1, characterized in that: The strong magnetic separation equipment is a permanent magnetic separator or an electromagnetic separator, and the magnetic field strength is set to 800-1200 Gauss, wherein: Permanent magnetic separators are suitable for materials with less metal impurities and can effectively remove iron materials through permanent magnets; Electromagnetic separators are suitable for materials with high metal impurity content. They can efficiently separate metal impurities by generating strong magnetic force through electromagnetic fields.

8. The process for crushing and grinding waste wind turbine blades according to claim 1, characterized in that: The return material system is an automated conveying system, and the system comprises: Belt conveyors, screw conveyors or pneumatic conveying systems are used to return incompletely ground particles to the mill for secondary grinding; The system also includes an automated control system that can automatically adjust the amount of returned material according to the material particle size and degree of crushing to ensure grinding efficiency.

9. The process for crushing and grinding waste wind turbine blades according to claim 1, characterized in that: The secondary screening equipment is a high-efficiency vibrating screen with a screen aperture of 0.5 mm, which is used to separate fine powder from incompletely crushed particles, wherein: The amplitude and frequency of the vibrating screen can be adjusted according to the material characteristics to ensure the best grading effect of the material; The screen material is made of wear-resistant metal mesh, which can operate stably for a long time and ensure the screening accuracy.

10. The waste wind turbine blade crushing and grinding process according to claim 1, characterized in that: The storage step is carried out in a storage bin, and the storage bin is equipped with a temperature control device to ensure the stability of the powder quality during storage. The temperature control device includes: Temperature sensors, heaters and coolers are used to maintain the temperature inside the storage silo between 10 and 25°C to prevent moisture and temperature fluctuations from causing powder agglomeration or deterioration.

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