Disposal device and method for fan retired blades based on low-temperature catalytic oxidation

Abstract

The invention relates to the technical field of heat treatment of low-calorific-value solid waste, in particular to a fan retired blade treatment device and method.The treatment device comprises an oxidation furnace, a heating rod and a catalysis unit, a material chamber and a gas storage chamber which communicate with each other are formed in the oxidation furnace, and the material chamber is located above the gas storage chamber; the material chamber is communicated with the smoke exhaust pipe; the gas storage chamber is communicated with the gas inlet pipe; the heating rod is arranged in the material chamber and used for heating materials; the catalytic unit is arranged around the heating rod, and after the catalytic unit is heated by the heating rod, a catalyst in the catalytic unit is gasified and diffused into the material chamber. The device can improve the action efficiency of a catalyst, reduce the oxidation activation energy of resin and accelerate the smoldering reaction rate; the ventilation and heat preservation performance of the furnace body is optimized, the oxygen utilization rate is increased, and the unburned carbon residual rate is reduced; accurate dynamic regulation and control of the reaction process are achieved, the stable smoldering state is maintained, and the treatment period is shortened.

Description

Technical Field

[0001] This application relates to the field of thermal treatment technology for low-calorific-value solid waste, and in particular to a device and method for treating decommissioned wind turbine blades based on low-temperature catalytic oxidation. Background Technology

[0002] Wind power, as one of the fastest-growing renewable energy sources in my country, has become a core supporting industry for achieving the "dual carbon" goals. However, the standard service life of wind turbine blades is only 20-25 years, and the industry has now entered a large-scale retirement cycle, showing a trend of "replacing smaller blades with larger ones." The pressure of disposing of retired blades is becoming increasingly prominent. How to achieve efficient, low-consumption, and environmentally friendly disposal of scrapped blades has become a major technical challenge spanning the wind power industry and the solid waste disposal field.

[0003] The main component of the scrapped blades is made of resin-glass fiber composite material (containing 30% resin and 60% glass fiber). The characteristics of this component lead to two major bottlenecks in its disposal: First, the calorific value is extremely low (less than 10 MJ / kg, only 1 / 3 of that of coal), and a large amount of non-combustible glass fiber is prone to melting and coking at high temperatures, which seriously hinders the combustion process. Second, traditional disposal technologies have significant defects. Among them, mechanical processing and chemical dissolution technologies have low resource utilization. Traditional thermal disposal technologies such as pyrolysis / incineration require a large amount of auxiliary fuel to maintain high temperatures, resulting in excessive energy consumption and often negative net energy output, making them economically unfeasible. Traditional smoldering devices face problems such as high unburned carbon residue rates, as high as 20%-30%, poor combustion stability, and long disposal cycles, making it difficult to meet the needs of large-scale disposal.

[0004] Smoldering technology, as a low-temperature oxidation (200-500℃) self-sustaining combustion technology for organic components, requires only initial ignition energy for continuous reaction. Its low-temperature characteristics simultaneously avoid the energy consumption of high-temperature maintenance and the risk of glass fiber melting and coking, making it an ideal technology for disposing of blade composite materials. However, existing smoldering devices have slow smoldering reaction rates, long single-furnace waste disposal cycles, and a large amount of unburned carbon residue, which limits their application effectiveness in the disposal of decommissioned wind turbine blades. To address these issues, this invention proposes a low-temperature catalytic oxidation-based device and method for disposing of decommissioned wind turbine blades, aiming to solve the aforementioned technical problems. Summary of the Invention

[0005] This application provides a device and method for disposing of decommissioned wind turbine blades based on low-temperature catalytic oxidation, which solves the problems of slow smoldering reaction rate, long waste disposal cycle per furnace, and large amount of unburned carbon residue in the prior art.

[0006] On the one hand, this application provides a device for disposing of decommissioned wind turbine blades based on low-temperature catalytic oxidation, characterized in that it includes: An oxidation furnace has a material chamber and a gas storage chamber that are connected to each other. The material chamber is located above the gas storage chamber and is connected to the exhaust pipe. The gas storage chamber is connected to the gas inlet pipe. Heating rods are installed in the material chamber to heat the materials; The catalytic unit is located around the heating rod. After being heated by the heating rod, the catalyst inside the catalytic unit is vaporized and diffused into the material chamber.

[0007] In one possible design, the catalytic unit includes a shell and a catalyst disposed within the shell. The shell has micropores, and the catalyst includes potassium nitrate, sodium chloride, and potassium chloride.

[0008] In one possible design, the molar ratio of potassium nitrate:sodium chloride:potassium chloride is 6:2:2.

[0009] In one possible design, the oxidation furnace is equipped with a sieve plate that separates the material chamber from the gas storage chamber, and the heating rods and catalytic unit are mounted on the sieve plate.

[0010] In one possible design, the oxidation furnace includes a base furnace body and foamed metal segments. Multiple foamed metal segments are intermittently embedded in the base furnace body along its height direction, and each foamed metal segment has several pores formed on it.

[0011] In one possible design, the porosity of the foamed metal segment gradually decreases from bottom to top along the height of the base furnace body.

[0012] In one possible design, the base furnace body is a ring-shaped steel structure, and the foamed metal section is a ring-shaped foamed metal composite. The base furnace body and the foamed metal section are connected alternately at intervals in the height direction.

[0013] One possible design also includes: Temperature sensors, multiple temperature sensors are distributed along the height direction on the inner wall of the oxidation furnace; A wind speed sensor is installed inside the smoke exhaust pipe 2; An oxygen concentration sensor is installed inside the flue pipe 2.

[0014] In one possible design, a storage silo and an ash separation silo are also included. The storage silo is equipped with an agitator, and a basic furnace body is set between the storage silo and the feed inlet of the oxidizer, and between the ash separation silo and the slag discharge outlet of the oxidizer.

[0015] On the other hand, this application also provides a method for disposing of decommissioned wind turbine blades, employing the wind turbine blade disposal device based on low-temperature catalytic oxidation as described above, the method comprising: After the leaf fragments are premixed with quartz, they are filled into the material chamber of the oxidation furnace; The heating rod is heated to the first preset temperature and kept at that temperature for a preset time. The catalyst is heated and vaporized, and then permeates into the micropores of the material in the material chamber. The heating rod triggers the ignition of the material. After the average temperature of the material reaches the second preset temperature, gas is introduced into the gas storage chamber of the oxidation furnace to initiate a self-sustaining smoldering reaction of the material. The smoldering wave propagates upward with the airflow, and the slight negative pressure inside the oxidation furnace drives the air outside the oxidation furnace to permeate into the oxidation furnace through the side wall.

[0016] The beneficial effects of this application are as follows: The wind turbine blade disposal device based on low-temperature catalytic oxidation of this application uses an alkali metal composite catalyst, which is heated to form a Na-K solid solution, significantly reducing the catalyst melting temperature and resin oxidation activation energy. The blade waste disposal rate is 36% higher than that of traditional technology, and the disposal cycle is significantly shortened.

[0017] The oxidation furnace uses gradient porous foam metal sections, which, combined with the airflow inside the furnace, can form a slight negative pressure on the inner wall, thereby automatically drawing in air. The oxygen flux on the wall is significantly increased, and the unburned carbon residue rate is reduced from 20%-30% in traditional technologies to below 2%, resulting in more thorough treatment.

[0018] By using multiple sensors for real-time monitoring and dynamic control, a stable smoldering temperature and wave velocity are maintained, with reaction rate fluctuations of less than ±5%, thus avoiding the lag defects of traditional static control.

[0019] The low-temperature catalytic oxidation characteristic avoids the energy consumption required to maintain high temperatures, eliminates the need for large amounts of auxiliary fuel, and inhibits the melting and coking of glass fibers; the recycling of quartz sand reduces material costs, achieving an overall efficient, low-consumption, and environmentally friendly disposal process.

[0020] The wind turbine blade disposal method provided in this application, by employing the wind turbine blade disposal device based on low-temperature catalytic oxidation as described in this application, simultaneously incorporates all the aforementioned advantages of the wind turbine blade disposal device based on low-temperature catalytic oxidation. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the specific embodiments of this application or the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0022] Figure 1 A schematic diagram of the structure of the wind turbine decommissioned blade disposal device based on low-temperature catalytic oxidation provided in the embodiments of this application. Figure 1 ; Figure 2A schematic diagram of the structure of the wind turbine decommissioned blade disposal device based on low-temperature catalytic oxidation provided in the embodiments of this application. Figure 2 ; Figure 3 Microstructure and atomic distribution diagram of the catalyst in the low-temperature catalytic oxidation-based wind turbine blade disposal device provided in the embodiments of this application; Figure 4 A flowchart illustrating a method for disposing of decommissioned wind turbine blades provided in an embodiment of this application.

[0023] Figure label: 100. Oxidation furnace; 110. Material chamber; 120. Gas storage chamber; 130. Basic furnace body; 140. Foamed metal section; 150. Screen plate; 210. Exhaust pipe; 220. Inlet pipe; 300. Heating rod; 400. Catalytic unit; 510. Temperature sensor; 520. Wind speed sensor; 530. Oxygen concentration sensor; 600. Storage silo; 700. Agitator; 800. Ash and slag separation silo; 900. Basic furnace body. Detailed Implementation

[0024] The technical solutions of this application will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0025] The following is combined Figures 1-4 This application describes a wind turbine blade decommissioning device based on low-temperature catalytic oxidation provided in the embodiments of this application.

[0026] Reference Figure 1 As shown in the embodiment of this application, the wind turbine decommissioned blade disposal device based on low-temperature catalytic oxidation includes an oxidation furnace 100, a heating rod 300, and a catalytic unit 400.

[0027] The oxidizer 100 contains a connected material chamber 110 and a gas storage chamber 120. The material chamber 110 is located above the gas storage chamber 120 and is used to contain the mixture of leaf fragments and quartz to be processed. The material chamber 110 is connected to the exhaust pipe 210 for discharging reaction waste gas. The gas storage chamber 120 is connected to the air inlet pipe 220 for introducing air to maintain combustion. A sieve plate 150 is provided inside the oxidizer 100, which separates the material chamber 110 from the gas storage chamber 120. The sieve plate 150 is made of foamed metal with a porosity of 40%, which serves both to ensure uniform airflow distribution and to support the material.

[0028] In some embodiments, the oxidation furnace 100 includes a base furnace body 130 and foamed metal segments 140. Multiple foamed metal segments 140 are spaced apart and embedded in the base furnace body 130 along its height direction, and each foamed metal segment 140 has a plurality of pores. Specifically, the base furnace body 130 is a ring-shaped steel structure, serving both load-bearing and sealing functions. The foamed metal segments 140 are ring-shaped foamed metal composites. The base furnace body 130 and the foamed metal segments 140 are alternately connected in the height direction, balancing structural strength and permeability.

[0029] In some embodiments, along the height direction of the base furnace body 130, the porosity of the foamed metal section 140 gradually decreases from bottom to top, with the lower layer having a porosity of 50-60%, which can enhance initial oxygen permeation, and the upper layer having a porosity reduced to 40%, which can balance heat preservation and reduce heat dissipation. For example, the porosity of the foamed metal section 140 from bottom to top is 60%, 50%, and 40%.

[0030] Heating rods 300 are disposed within the material chamber 110 and mounted on the sieve plate 150. They are used to heat the material to trigger ignition and to provide heat for gasification to the catalytic unit 400. Preferably, three rod-shaped insert heaters are used, symmetrically distributed within the furnace to ensure uniform heating.

[0031] The catalytic unit 400 is disposed around the heating rod 300. Heated by the heating rod 300, the catalyst inside the catalytic unit 400 vaporizes and diffuses into the material chamber 110. Specifically, the catalytic unit 400 includes a shell and a catalyst disposed within the shell. The shell is fitted onto the heating rod 300 and has micropores to facilitate the permeation of the vaporized catalyst into the material. Preferably, the shell has a thermal conductivity >200W / m. Made of K, a highly thermally conductive metal, to enhance heat transfer. The catalyst includes potassium nitrate (K₂NO₃), sodium chloride (NaCl), and potassium chloride (KCl), which can form a stable Na-K solid solution, lowering the catalyst melting temperature and enabling rapid vaporization and diffusion.

[0032] In this implementation scheme, the molar ratio of the composite alkali metal catalyst has different effects on the low-temperature oxidation reaction process of the resin. Therefore, the two key indicators, the peak smoldering temperature and the blade waste disposal rate, were tested under different ratios. The specific test data are shown in the table below.

[0033] Table 1. Relationship between different molar ratios of composite alkali metal catalysts and smoldering peak temperature and blade waste disposal rate.

[0034] Detailed analysis of the data in Table 1: The blade waste disposal rate of control group 1 was set as 1. The optimal ratio group was group 3, where the peak smoldering temperature was 668℃ and the blade waste disposal rate reached 1.36 (relative value), exhibiting the best overall performance. The second-best range was the molar ratio from 4:3:3 to 2:4:4 (groups 4 and 5), also maintaining relatively high disposal efficiency. Inefficient groups, such as those with ratios of 0:1:1 and 8:1:1, showed lower disposal rates. These performance differences are related to the degree of Na-K solid solution formation. The high-efficiency range favors the formation of the low-Na, high-K solid solution KNaCl(ss), thereby promoting the overall gasification of the catalyst.

[0035] Therefore, the above analysis shows that the composite alkali metal catalyst has a promoting effect on the smoldering reaction. Among them, the composite alkali metal catalyst has the best promoting effect on the smoldering reaction when the molar ratio of K2NO3 / NaCl / KCl is 6:2:2.

[0036] In some embodiments, the inner wall of the oxidizing furnace 100 is also provided with a plurality of temperature sensors 510, which are evenly distributed along the height direction to monitor the smoldering temperature in different areas. For example, a total of five sets of temperature sensors 510 are provided, from bottom to top, namely temperature sensor 1, temperature sensor 2, temperature sensor 3, temperature sensor 4, and temperature sensor 510.

[0037] A wind speed sensor 520 and an oxygen concentration sensor 530 are also installed in the exhaust pipe 210 to monitor the exhaust gas flow rate and oxygen concentration, respectively, to provide data support for regulation.

[0038] In some embodiments, the device includes a storage silo 600 and an ash separation silo 800. An agitator 700, employing a dual-shaft differential speed agitator 700 with a rotation speed of 30 / 15 rpm, is installed inside the storage silo 600 for premixing the blade fragments and quartz. A basic furnace body 900, such as a tubular screw conveyor, is installed between the storage silo 600 and the feed inlet of the oxidation furnace 100, and between the ash separation silo 800 and the slag discharge outlet of the oxidation furnace 100, respectively, to achieve automated material conveying and residue recovery.

[0039] Reference Figure 4 As shown in the embodiments of this application, a method for disposing of decommissioned wind turbine blades is also provided. This method employs the low-temperature catalytic oxidation-based decommissioned wind turbine blade disposal device described in the above embodiments. The disposal method specifically includes the following steps: Material pretreatment: The decommissioned blades are crushed into fragments with a particle size of 5-10mm and mixed with quartz stone at a volume ratio of 1:1.2. The mixture is then added to the storage silo 600 and stirred for 15 minutes to form a homogeneous material. The homogeneous material is then pushed to the material chamber 110 of the oxidation furnace 100 through the basic furnace body 900, filling the chamber to 80% of the total height of the oxidation furnace 100.

[0040] Catalyst vaporization: Start heating rod 300, heat up to 600℃ and keep it at that temperature for 5 minutes. The catalyst in the catalytic unit 400 is heated and vaporized, and then permeates into the micropores of the material through the micropores of the shell.

[0041] Ignition trigger: The heating rod 300 continuously heats the material. When the bottom temperature sensor 510 detects that the average temperature of the material reaches 300℃, the ignition is determined to be successful, and the heating rod 300 is turned off.

[0042] Smoldering start-up: Air is introduced into the gas storage chamber 120 through the air inlet pipe 220. The air inlet flow rate is adjusted to form a slight negative pressure (-50Pa) in the furnace. The bottom material initiates a self-sustaining smoldering reaction. The smoldering wave propagates upward with the airflow. External air permeates into the material chamber 110 through the pores of the foam metal section 140.

[0043] Dynamic control: Temperature sensor 510, wind speed sensor 520, and oxygen concentration sensor 530 provide real-time feedback of temperature, wind speed, and oxygen concentration data. If the upstream temperature sensor 510 ( Figure 4 (Taking the No. 2 sensor as an example) If the data deviates from the bottom temperature history baseline curve, adjust the intake air flow and the 300 auxiliary power of the heating rod to maintain the smoldering wave velocity of 1.2-1.5 mm / s and the reaction temperature of 400℃±20℃.

[0044] Residue treatment: When the temperature sensor 510 detects that the temperature has dropped below 350℃, the treatment is deemed complete. The residue is discharged through the slag discharge port and sent from the basic furnace body 900 to the ash and slag separation bin 800. The quartz sand recovered by the vibrating screen is returned to the storage bin 600 for recycling.

[0045] In this embodiment, the blade waste disposal rate is increased by 36% compared with the traditional smoldering device, the unburned carbon residue rate is 1.8%, the single furnace disposal cycle is shortened by 40%, the quartz sand recovery rate reaches 92%, no auxiliary fuel needs to be added throughout the process, and the energy consumption is reduced by 65% ​​compared with the traditional thermal treatment technology.

[0046] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0047] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0048] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between components; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0049] In this application, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0050] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.

Claims

1. A device for disposing of decommissioned wind turbine blades based on low-temperature catalytic oxidation, characterized in that, include: An oxidation furnace, wherein a material chamber and a gas storage chamber are connected inside the oxidation furnace, the material chamber is located above the gas storage chamber, the material chamber is connected to the exhaust pipe, and the gas storage chamber is connected to the gas inlet pipe; A heating rod, disposed in the material chamber, is used to heat the material; A catalytic unit is disposed around the heating rod. After being heated by the heating rod, the catalyst inside the catalytic unit is vaporized and diffused into the material chamber.

2. The wind turbine blade decommissioning device based on low-temperature catalytic oxidation according to claim 1, characterized in that, The catalytic unit includes a shell and a catalyst disposed within the shell. The shell has micropores, and the catalyst includes potassium nitrate, sodium chloride, and potassium chloride.

3. The wind turbine blade decommissioning device based on low-temperature catalytic oxidation according to claim 2, characterized in that, The molar ratio of potassium nitrate:sodium chloride:potassium chloride is 6:2:

2.

4. The wind turbine blade decommissioning device based on low-temperature catalytic oxidation according to claim 1, characterized in that, The oxidation furnace is equipped with a sieve plate, which separates the material chamber from the gas storage chamber. The heating rod and the catalytic unit are mounted on the sieve plate.

5. The wind turbine blade decommissioning device based on low-temperature catalytic oxidation according to any one of claims 1-4, characterized in that, The oxidation furnace includes a base furnace body and foamed metal segments. Multiple foamed metal segments are interspersed on the base furnace body along the height direction, and each foamed metal segment has a number of pores formed on it.

6. The wind turbine blade decommissioning device based on low-temperature catalytic oxidation according to claim 5, characterized in that, Along the height direction of the basic furnace body, the porosity of the foamed metal segment gradually decreases from bottom to top.

7. The wind turbine blade decommissioning device based on low-temperature catalytic oxidation according to claim 5, characterized in that, The basic furnace body is a ring-shaped steel structure, and the foamed metal segment is a ring-shaped foamed metal composite. The basic furnace body and the foamed metal segment are connected alternately at intervals in the height direction.

8. The wind turbine blade decommissioning device based on low-temperature catalytic oxidation according to claim 5, characterized in that, Also includes: Temperature sensors, a plurality of which are distributed along the height direction on the inner wall of the oxidation furnace; A wind speed sensor is installed inside the exhaust pipe 2; An oxygen concentration sensor is installed inside the exhaust pipe 2.

9. The wind turbine blade decommissioning device based on low-temperature catalytic oxidation according to claim 1, characterized in that, It also includes a storage silo and an ash and slag separation silo. The storage silo is equipped with a stirrer. Basic furnace bodies are respectively installed between the storage silo and the feed inlet of the oxidation furnace, and between the ash and slag separation silo and the slag discharge outlet of the oxidation furnace.

10. A method for disposing of decommissioned wind turbine blades, characterized in that, The method of using the low-temperature catalytic oxidation-based decommissioned wind turbine blade disposal device according to any one of claims 1-9 includes: After the leaf fragments are premixed with quartz, they are filled into the material chamber of the oxidation furnace; The heating rod is heated to the first preset temperature and kept at that temperature for a preset time. The catalyst is heated and vaporized, and then permeates into the micropores of the material in the material chamber. The heating rod triggers the ignition of the material; After the average temperature of the material reaches the second preset temperature, gas is introduced into the gas storage chamber of the oxidation furnace to initiate a self-sustaining smoldering reaction of the material. The smoldering wave propagates upward with the airflow, and the slight negative pressure inside the oxidation furnace drives the air outside the oxidation furnace to permeate into the oxidation furnace through the side wall.

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