Under the environmental protection policy, how to deal with 10,000-ton retired wind turbine blades

Recently, a seminar on window pushing and industrial development model of wind power blades was organized in Beijing, and relevant industry associations focused on the recycling and post-processing of decommissioned blades
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There was a special discussion on how to promote the industrialization technology and efficient comprehensive utilization of blade recycling.
This is the first time that the wind power industry and the material industry have publicly discussed blade recycling and post-processing comprehensive utilization
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With the gradual exhaustion of traditional fossil energy sources such as coal, oil, and natural gas, the development and utilization of new energy sources such as wind energy and solar energy have also attracted more and more attention, and has become one of the most promising projects in the energy field.
Rapid development at home and abroad
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The development of wind power in China began in the 1950s.
The early development was mainly used for the problem of power vacancies in islands and remote areas, mainly the construction of non-grid-connected small wind turbines
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In the late 1970s, China began to study grid-connected wind power, mainly by introducing foreign wind turbines to build demonstration farms.

In the process of continuous development, China’s wind power industry has experienced an early demonstration stage, industrialization exploration stage, rapid growth stage, rapid development stage, adjustment stage, and a steady growth stage starting in 2014
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After the early reshuffle, the phenomenon of overheating of China's wind power industry has been curbed to a certain extent, and the development model has changed from emphasizing scale and speed to emphasizing efficiency and quality

Among the domestic complete machine manufacturers, Xinjiang Goldwind, Zhejiang Yunda, Dalian Heavy Industry Group, and Dongfang Steam Turbine Factory have good market prospects and occupy a large share of the market
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In the wind power industry, the situation of the blade market largely determines the situation of the complete machine market

At present, global wind power companies are in a highly competitive development process.
Domestic developers are catching up.
Compared with foreign wind power giants, there is still a certain distance
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Wind power blades affect the development of the entire wind power industry.

In the current development of wind power blades, composite materials are the most widely used
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At present, the application of composite materials in wind power generation is mainly in the manufacture of rotor blades, nacelle covers and fairings

In the history of the rise of wind turbines for more than 100 years, blade materials have experienced wooden blades, cloth-skinned blades, aluminum alloy blades and so on
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With the emergence of networked wind turbines, wind power has entered a period of rapid development.

The wind turbine blade is a thin shell structure made of composite materials, which is generally composed of three parts: the root, the outer shell, and stiffeners or beams.
The composite material generally accounts for more than 90% of the weight of the entire wind turbine blade
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At the beginning of the development of composite blades, cheap glass fiber reinforced unsaturated polyester resin system was used, and it is still the material used in most blades until today

Based on the current high price of carbon fiber in the world, some people think that the use of carbon fiber in blade production is too expensive and should not be used.
In fact, this is not the case.
On the one hand, due to the increase in blade length, the rigidity requirements are more stringent.
In the manufacture of larger blades, the stiffness of carbon fiber is about three times that of other materials, such as glass fiber, and the stiffness of the composite material is about twice that of glass fiber reinforced plastic.
In this sense, the introduction of carbon fiber is necessary and necessary; On the other hand, due to the increase in the size of the blade, its mass is becoming more and more huge.
The introduction of high-performance carbon fiber can reduce the weight of the blade to a large extent.
, Platforms and tower covers can also be lightweight, which can reduce the cost of wind turbines as a whole, offset or partially offset the cost increase caused by the introduction of carbon fiber
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With the manufacture and operation of large and ultra-large offshore wind turbines, the era of large-scale application of carbon fiber in wind power blades is not far away

In the blade manufacturing process, the traditional blade production generally adopts the mold opening process, especially the hand lay-up method.
A large amount of volatile and toxic gases such as styrene will be generated during the production process, which will bring harm to the operator and the environment; As the size of the blades increases, in order to ensure the smooth operation of the generator and the safety of the tower, it is necessary to ensure that the blades are light and have a uniform mass distribution
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This promotes the development of blade production technology from open mold to closed mold
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The use of closed-mold technology, such as the popular vacuum resin injection molding method, can not only greatly reduce the volatilization of styrene during the molding process, but also make it easier to accurately control the resin content, thereby ensuring the uniformity of the composite blade mass distribution, and Improve the quality stability of the blade
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The development of wind power is gratifying.
However, the recycling of retired blades has been ignored by everyone.
As time goes by, more and more people will pay attention to it.
What causes the current result? What kind of composite materials, even "recycling" should be discussed on the table?

Its professional name is fiber reinforced resin composite material
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The resins mentioned here include various types of epoxy resins, unsaturated resins and polyurethane resins that are being used and promoted
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Of course, the biggest feature of composite materials is light weight and high strength.
The unit density is only 1/3 of that of steel.
The mechanical properties of materials of the same weight are several times that of metals; and the performance can be designed.
The difference from metal materials is anisotropy.
The physical properties of the product are required to be designed, and the fan blades have such functional requirements and use composite materials as the blade material
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However, one of the characteristics of composite materials is that the chemical process of the material cannot be reversed.
Once it is cured and formed, it cannot return to the original material matrix properties.
More importantly, it cannot be degraded if it is not processed by a new process.
This is a high pressure for the current environmental protection policy.
In terms of it, it is a huge threat
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The recycling and reuse of fan blades has become a pain point in the industry
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The report clearly requires that "strengthen the disposal of solid waste and garbage, promote the overall conservation and recycling of resources, and realize the circular link between the production system and the living system"
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The Law on the Prevention and Control of Environmental Pollution by Solid Wastes, which came into effect on September 1, 2020, is known as the “Strict Solid Waste Law in History”
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The new "Solid Waste Law" has been more stringent in five aspects: the supervision and management system for the prevention and control of environmental pollution by solid waste, the prevention and control system for environmental pollution by industrial solid waste, the prevention and control system for domestic waste pollution, the extended producer responsibility system, and the industrial solid waste discharge permit system.
Regulations
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Under the high-pressure environmental protection policy, the recycling and post-processing of blades has become a major problem that the industry is about to face, because no matter which recycling method the blade adopts, it requires a high cost and is subject to the strict institutional constraints of the "solid waste regulations"
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Thousand-ton blades will be recycled soon: 10,000-ton blades will be dealt with in 2026
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According to statistics from industry conferences, as of the end of 2020, the number of wind power installed in the country exceeded 140 million, and by the end of 2021, the actual number of wind turbines that could be retired exceeded 383,000 kilowatts (this is unofficial data, and it is estimated that there are differences in statistical calibers).
The current consumption of blades per kilowatt is calculated at 16kg/kw.
By the end of this year, the weight of composite blades of wind turbines that can actually be retired is as high as 6096 tons (roughly estimated)
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According to industry statistics (the table below), the amount of blades in 2006 exceeded 20,000 tons for the first time, which means that the blade recycling industry in 2026 will usher in the first big test of wind power retirement
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By 2029, the annual volume of processing and recycling blades will reach 220,000 tons, and its scale will reach about 527,000 tons in 2035
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Post-processing of blades is still in its infancy: the industry still has time to deal with it
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From the perspective of scale, the annual blade processing capacity will be between 1,000-2,000 tons until 2023.
From the perspective of the comprehensive utilization of composite materials, it is still in the engineering test stage.
In other words, our industry still has 2-3 Years to carry out experimental research and engineering scale applications in this area
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Starting from 2024, the annual scale will begin to reach more than 5,000 tons.
This is not our small workshop->
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At present, the retired blades are simply treated, but they are all based on temporary treatment.
After the real large-scale retired wind turbine blades begin, it is necessary to consider how to do a good job in the comprehensive utilization of the retired blades on the basis of meeting environmental protection.
Turn waste into treasure
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In fact, our blade industry companies are also taking action, including Sinoma Technology, Times New Materials, and Chengfei Zhongtong.
They are also doing research in this area.
They have also received national support, but there is still a long way to go before large-scale applications.
It’s a long way to go.
It needs to be pointed out that I personally believe that as the most familiar with blades, the blade company should be the most important unit for blade recycling and comprehensive utilization, and it should be the main implementer of the recycling and post-processing, and the wind turbine owner The person must consider the cost of the wind turbine decommissioning treatment
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Recycling and post-processing of blades: future wind farms need to prepare reserves for wind turbine retirement as a part of the full life cycle.
Wind turbine retirement also requires cost.
This may not be considered in the past wind farms, but at the end of the actual life.
At that time, a sum of money needs to be spent on the retirement of the wind turbine
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Except for blades, most of the other metal parts can be recycled, but blades are industrial non-degradable solid waste, and a solid waste treatment fund is required.
Unlike the regeneration of towers and unit metal parts, the blades need to be recycled.
The corresponding solid waste treatment costs of the processing unit, coupled with the realization of a part of the comprehensive utilization after the blade recovery, makes the blade recovery business model established, with the most basic industry profit (the enterprise can operate normally), then the wind power industry's wind turbines are decommissioned and recycled Realize the real green development
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In addition, the industry is also formulating relevant solid waste treatment standards for blade composite materials to determine whether the recycling of blades in the future meets the environmental protection policy.
This is also a new issue we face
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The green and circular development of the wind power equipment industry is the foundation for the healthy development of the wind power industry.
The recycling and post-processing of blades is also a new problem that has arisen and faced at a certain stage of development.
The industry is paying attention, and enterprises should pay more attention to it, especially wind farm owners.
It is another important historical task of wind turbine blades to spend the least money to realize green comprehensive utilization of solid waste such as blades while avoiding the punishment of high-pressure environmental protection policies
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