Method for recycling microfiberglass waste

Abstract

The application discloses a recycling method of micro-fiber glass wool waste, which comprises the following steps: (1) wet pretreatment: the micro-fiber glass wool waste is put into a liquid medium, and is stirred to be fully soaked and preliminarily dispersed; then, ultrasonic treatment is carried out; filtration, drying, and glass fibers are obtained; (2) high-temperature melting separation: the glass fibers are mixed with glass raw materials, heated to 1300-1500 DEG C and kept for 1-2 hours; cooling, separation, and lower transparent glass blocks are reserved; (3) component recovery remelting: the transparent glass blocks are mixed with glass raw materials, and are subjected to sufficient melting and homogenization treatment; cooling, and recycled glass blocks are obtained. The recycling method of the micro-fiber glass wool waste can remove impurities and recover components through wet pretreatment, melting separation and component recovery, and can realize high-quality recycling of the glass wool waste; and on this basis, CFD simulation optimization of dust removal pipelines can be supplemented, so that the energy efficiency in the recycling process is improved.

Description

Technical Field

[0001] This invention relates to a method for recycling and reusing microfiber glass wool waste, belonging to the field of glass fiber waste recycling technology. Background Technology

[0002] Glass fiber (also known as glass fiber wool) is a commonly used thermal insulation material, widely used in construction and industrial fields due to its light weight and low thermal conductivity. During the production and processing of glass fiber, as well as during building demolition, a large amount of fine glass fiber waste is generated. This waste, containing binder residues and construction impurities, is often directly disposed of as solid waste through landfill or incineration, wasting valuable inorganic glass fiber resources and potentially causing long-term environmental damage. With increasingly stringent environmental regulations and the promotion of the circular economy concept, how to efficiently recycle and utilize glass fiber waste and reduce industrial solid waste emissions has become an urgent problem to be solved in the glass fiber materials field.

[0003] However, the recycling and reuse of waste glass wool faces numerous technical challenges. Waste glass wool is often mixed with calcium and sulfur impurities, primarily originating from other materials that adhere during production and use. For example, in building insulation demolition waste, glass wool is often mixed with gypsum board fragments and cement dust, leading to a significant increase in calcium and sulfur content. Furthermore, some binders or additives used in glass wool products may leave behind impurities such as calcium oxide and sulfides after combustion. These calcium and sulfur impurities severely affect the remelting quality of waste glass wool: excessive calcium and sulfur can cause abnormal viscosity and surface tension in the glass melt, easily leading to crystallization and precipitates, reducing the mechanical properties and spinnability of the resulting glass; sulfides and sulfate impurities may decompose and release gases during melting, causing blistering and foaming of the melt, interfering with normal fiber drawing processes. Therefore, the traditional practice of directly adding waste glass wool to glass furnaces is impractical; untreated impurities will result in substandard fiber quality or even damage to equipment. Some fiberglass manufacturers have attempted to remelt small amounts of clean waste materials, but the addition ratio is limited and the impurity content needs to be strictly controlled. Once the waste contains impurities such as gypsum powder and dust, its reuse rate is almost zero, and it can only be discarded. Therefore, in order to realize the resource utilization of fiberglass waste, it is necessary to develop a pretreatment and melting process that can efficiently remove harmful impurities such as calcium and sulfur.

[0004] In the field of solid waste treatment, common methods include physical sorting, chemical leaching, and high-temperature melting. For example, for industrial waste containing calcium and sulfur, wet leaching can dissolve and remove some soluble salts, while high-temperature melting can transform the waste into an inert glass and capture heavy metals. However, specifically for glass wool waste, there is a lack of specialized recycling processes. Glass wool fibers are fine in diameter and have a large specific surface area. When directly heated at high temperatures, the organic binder will burn, and the fine fibers may scatter, causing loss and pollution. At the same time, impurities easily form refractory inclusions during the melting process, and the composition of the glass blocks obtained after simple melting often deviates from product requirements, making it difficult to use directly in fiber production. These problems have not yet been effectively solved.

[0005] On the other hand, in the recycling of glass wool waste, processes such as high-temperature melting and fiber processing usually require dust removal systems to capture furnace exhaust gas and fiber dust, preventing the emission of fine glass fibers and dust into the environment. Glass fiber dust is lightweight and fibrous; if dust removal measures are inadequate, the escape of tail fibers (i.e., the leakage of fine glass fibers carried in the exhaust gas) will cause air pollution and health hazards, and also signify the loss of valuable fiber resources. Traditional dust removal systems (such as bag filters and cyclone separators) are technically mature in handling general dust, but their collection efficiency and resistance characteristics may decrease when dealing with fibrous particles, especially in cases of poorly designed dust removal ducts. This can lead to uneven local flow field distribution: high shear velocities can shear fibers into even finer, harder-to-capture particles; backflow eddies can cause some fibers to flow around without entering the filter; and localized high-temperature areas may be caused by the accumulation of hot exhaust gas or stagnant flow, increasing energy loss and potentially damaging pipes and filter bags. These problems all reduce the effectiveness and energy efficiency of the dust removal system. Traditional pipeline design relies mainly on experience or simplified formulas for calculation, making it difficult to detect the aforementioned detailed problems in a timely manner.

[0006] With the development of computer simulation technology, Computational Fluid Dynamics (CFD) has provided a powerful tool for optimizing flow fields in industrial pipelines. By performing CFD simulations on dust collection pipelines during the design phase, the distribution of airflow and fiber particles inside the pipeline can be intuitively understood, undesirable flow regions can be identified, and structural improvements can be guided. For example, CFD simulations can reveal the velocity distribution and vortex morphology of airflow within a bend, thus prompting designers to improve the flow field by increasing the bend curvature or adding flow guiding devices. If CFD co-optimization can be applied to the design of dust collection pipelines in glass wool waste treatment systems, it is expected to significantly improve the collection efficiency of fiber dust, reduce tail fiber emissions, and simultaneously reduce system pressure loss and energy consumption. This approach of emphasizing both process and equipment and optimizing them as a whole will help build more environmentally friendly and efficient glass wool waste recycling production lines. Summary of the Invention

[0007] In view of the above-mentioned prior art, the present invention provides a method for recycling and reusing microfiber glass wool waste, and further provides a CFD collaborative optimization method.

[0008] This invention is achieved through the following technical solution: A method for recycling and reusing microfiber glass wool waste includes the following steps: (1) Wet pretreatment: The microfiber glass wool waste is put into water and stirred to fully wet and initially disperse it. The soluble calcium and sulfur impurities on the surface and inside of the microfiber glass wool waste are dissolved. Then, ultrasonic treatment is performed to loosen the fiber bundles and promote the removal of impurities. Then, the filter is filtered and the filter residue is dried to obtain glass fiber. Wet pretreatment can destroy the bonding layer on the fiber surface and remove fluxing ions, which can significantly reduce the content of Ca and S impurities in the microfiber glass wool waste, which is beneficial to the subsequent liquid-liquid immiscible phase separation of the high temperature melt. (2) High-temperature melting and separation: The glass fibers obtained by the above wet pretreatment are mixed with an appropriate amount of glass raw materials to restore the content of the main components of the mixture (including SiO2, Al2O3, MgO, Na2O and K2O) to the same or similar content as the main components of the finished glass, so as to supplement the silicon and alkali metal components and adjust the CaO / MgO ratio; heat to 1300-1500℃ and hold for melting for 1-2 hours. Based on the interfacial tension difference induced by pretreatment, the Ca and S impurities in the glass melt form independent impurity phases (slag phase or precipitate phase) that are immiscible with the silicate melt phase and aggregate and precipitate; cool to produce upper and lower phase stratification, separate the two phases, and retain the lower transparent glass block; (3) Composition recovery and remelting: The transparent glass block obtained by high-temperature melting and separation is mixed with an appropriate amount of glass raw materials. By adding raw materials, the content of the main components of the mixture (including SiO2, Al2O3, CaO, MgO, Na2O and K2O) is restored to the same or similar to the content of the main components of the finished glass. The mixture is fully melted and homogenized, cooled, and a recycled glass block is obtained.

[0009] It also includes the following steps: (4) Preparation of glass fiber cotton: glass fiber cotton is prepared by conventional process using recycled glass blocks as raw materials. The glass fiber cotton production line drawing section is equipped with a tail gas dust removal system. The tail gas dust removal system includes a cyclone dust collector. The inlet of the cyclone dust collector is connected to the tail gas outlet through a vertical bend pipe. The outlet at the top of the cyclone dust collector is connected to the fan inlet through a return bend pipe.

[0010] Furthermore, for the exhaust gas dust removal system, considering the thermal sensitivity and fragility of recycled glass due to its reduced viscosity, CFD simulation analysis was used for structural optimization. The optimized scheme involves increasing the radius of curvature of the pipe bends to 3-5 times the pipe diameter, creating a low-shear transport flow field, controlling the maximum shear stress on the pipe wall below 1.1 Pa, and eliminating backflow stagnation zones within the pipe to suppress secondary breakage and thermal adhesion of recycled fibers during transport. Specifically, the radius of curvature of the vertical bends is set to 4 times the pipe diameter, and the radius of curvature of the return bends is set to 3 times the pipe diameter. Guide plates are installed on the outside of the vertical and return bends to further reduce turbulent kinetic energy. The optimized dust removal pipeline system exhibits lower pressure loss and higher fiber capture efficiency. Specifically, the uniformity of the airflow velocity field at the dust collector inlet is improved, local high-temperature areas are eliminated, and the concentration of escaped tail fibers is reduced by at least 30% compared to before optimization, thereby improving the energy efficiency ratio of the dust removal system and reducing the emission of glass fiber particles into the environment.

[0011] Further, in step (1), the parameters for ultrasonic treatment are: power 300–700 W, frequency 15–40 kHz, and treatment time 10–30 minutes. Preferably, the parameters are: power 500 W, frequency 25 kHz, and treatment time 20 minutes.

[0012] Furthermore, in steps (2) and (3), the glass raw materials are selected from any one or more of the following: quartz sand, soda ash, feldspar, limestone, borax, or alumina powder.

[0013] Further, in steps (2) and (3), after adding glass raw materials, the content of SiO2 in the mixture is 67%–69%, the content of Al2O3 is 2.5%–3.5%, the content of MgO is 2.5%–3.5%, the content of Na2O is 17%–19%, and the content of K2O is 1%–2.5%. Preferably, the content of SiO2 in the mixture is 68%, the content of Al2O3 is 3%, the content of MgO is 3%, the content of Na2O is 18%, and the content of K2O is 2%.

[0014] Preferably, in step (2), the temperature is heated to 1400°C and kept at that temperature for 1 hour to melt the material.

[0015] Preferably, in step (3), the parameters for melting and homogenizing are: heating to 1550°C for 30 minutes, raising the temperature to 1600°C for clarification for 15 minutes, and then lowering the temperature to 1200°C for homogenization for 30 minutes.

[0016] Furthermore, in step (3), a clarifying agent is added to the mixture to promote the subsequent removal of bubbles. The clarifying agent is composed of sodium nitrate and sodium sulfate.

[0017] The present invention provides a method for recycling and reusing microfiber glass wool waste, focusing on solving the following technical problem: how to efficiently remove impurities such as Ca and S from glass wool waste and ensure that the composition of the recycled glass is consistent with that of the finished glass wool, thereby overcoming the problems of large compositional deviation and poor fiber performance after direct melting of existing waste materials. To solve this technical problem, the present invention first uses wet pretreatment to dissolve soluble calcium and sulfur-containing impurities, then removes the Ca and S impurities from the slag through high-temperature melting and phase separation, and finally restores the composition of the recycled glass block to be consistent with that of the finished glass. Specifically, the off-line waste generated during the microfiber glass wool production process is selected as raw material W0 and subjected to wet pretreatment. Specifically, W0 is added to an appropriate amount of water, fully soaked and disintegrated under mechanical stirring, and then ultrasonic oscillation is applied to accelerate the dispersion of fiber bundles and the removal of impurities from the fiber surface. After thorough stirring and ultrasonic treatment, the slurry is separated into solid and liquid components using a filter screen. The glass fibers in the filter residue are rinsed with clean water to remove impurities and dried at low temperature to obtain a pre-removed fiber sample W1. The W1 sample had been largely free of soluble salt impurities and larger solid debris, but microscopic observation revealed the potential presence of small inorganic particles (such as calcium salt crystals). Next, W1 was mixed with glass raw materials such as quartz sand and soda ash in a specific ratio and then melted in a high-temperature furnace. Maintaining a melting temperature of approximately 1400°C for an appropriate time allowed the glass wool waste and the newly added raw materials to fully melt and undergo high-temperature phase separation. Utilizing the difference in density and solubility between the impurities and silicate glass, the melt cooled to create two phases: an upper layer forming a milky white solid (W1-2) and a lower layer a transparent glassy phase (W1-1). The cooled upper white solid was completely peeled off and removed, leaving only the lower transparent and homogeneous glass block (corresponding to the subsequent W2 sample) as recycled raw material. Chemical composition analysis showed that the content of harmful impurities sulfur and calcium in sample W2 was significantly reduced compared to W1. Correspondingly, most of the sulfur and excess calcium were enriched in the removed W1-2 slag, whose main components were sulfates such as CaSO4 and a small amount of unmelted quartz and other impurities. Thus, efficient separation of calcium and sulfur impurities in glass wool waste was achieved through wet pretreatment combined with high-temperature melting. Subsequently, in order to make the composition of W2 meet the requirements of finished glass, composition recovery treatment was carried out on W2. The amount of glass raw material to be added was calculated according to the analysis results, mixed with W2, and melted again. After secondary melting and clarification and homogenization, the recycled glass block was obtained by casting and cooling. In the XRD diffraction pattern of the recycled glass block, no obvious crystalline impurity peaks appeared, indicating that impurity phases such as sulfates had been effectively removed. The recycled glass is mainly composed of amorphous glass phase, with the same amorphous structure characteristics as the finished glass. Furthermore, the main oxide content of the recycled glass blocks is very close to that of the original finished glass blocks. It can be seen that the waste glass formula has been restored through composition compensation and remelting, so that the chemical composition of the recycled glass returns to the range of the finished glass formula. Moreover, the number of bubbles in the recycled glass and the finished glass is also similar.

[0018] Furthermore, after solving the aforementioned technical problems, this invention further optimizes the dust removal system using CFD simulation to overcome the issues of uneven flow field, high energy consumption, and fiber escape that may exist in traditional dust removal pipelines. Specifically, this invention conducts CFD simulation analysis and structural optimization of the exhaust gas dust removal system in the drawing section of a microfiber glass wool production line. First, a three-dimensional model of the cyclone dust collector and its connected pipeline geometry is created using CFD modeling. The model includes the entire flue gas flow path from the outlet of the drawing blower to the inlet of the induced draft fan, encompassing horizontal and vertical pipe sections, bends, and the cyclone separator body. The model boundary conditions are set with flue gas inlet velocity (calculated based on the exhaust volume of the drawing furnace), flue gas temperature field, and cyclone dust collector outlet parameters consistent with actual production, and considers glass fiber particles (discrete phase) with a certain concentration and particle size distribution carried in the flue gas. The k-Ω SST turbulence model is used to simulate gas-phase turbulence, combined with DPM (discrete phase model) to track the movement trajectory of fiber particles, to simulate the gas-solid two-phase flow within the pipeline. Simulation results show that the original system design exhibits unfavorable flow and heat transfer characteristics in certain local areas: At the vertical downflow duct at the cyclone dust collector inlet and at the sharp bend connecting to the dust collector, a local high-speed airflow zone appears. Under all operating conditions, the peak airflow velocity in this zone can reach approximately 34 m / s, significantly higher than the average flow velocity of approximately 25 m / s in the rest of the system. Accompanying this high speed are drastic changes in pressure and shear force, resulting in a high-pressure zone and high shear stress concentration on the outer wall of the sharp bend, accompanied by a low-pressure vortex separation zone nearby. This coupling phenomenon of "geometric abrupt change—local high speed—high shear / low-pressure backflow" intensifies local turbulence and mixing, leading to significant flow field inhomogeneity and additional energy loss. Simultaneously, at the inlet and outlet of the cyclone dust collector, the abrupt change in airflow direction generates strong vortices and turbulent structures, forming a high-turbulence region at the top of the dust collector, corresponding to a severe dissipation of gas kinetic energy. The aforementioned turbulent and recirculating structures, on the one hand, rapidly carry high-temperature airflow and heat out of the system, resulting in a decrease in effective heat utilization; on the other hand, they lead to uneven ventilation distribution, with localized low-speed stagnation zones and flow separation, weakening the heat exchange effect and causing uneven temperature distribution. These factors negatively impact temperature control and fiber collection in the fiber drawing process: localized overheating can easily cause fiber melting and adhesion, carbon buildup and blockage, while undercooling may cause premature fiber solidification and deposition, and high-speed turbulence can directly carry uncaptured fine fiber particles out of the system. For example, under the original operating conditions, the exhaust gas at the cyclone dust collector outlet still contains a large number of fine glass wool fiber particles (particle streamlines show fibers escaping with the airflow), indicating that the existing dust collection system has structural deficiencies in capturing fine fibers under high-temperature and high-speed conditions. To solve the above problems, this invention performs targeted structural optimization of the dust collection pipeline system based on simulation results. While maintaining the overall layout of the pipeline route, the focus is on optimizing the curvature radius of the bends.By increasing the curvature of the bends, the airflow turns more smoothly, weakening the strong centrifugal effect and adverse pressure gradient at the original sharp bends. In the preferred embodiment of this invention, the radius of curvature of the lower 180° bend section is increased from approximately 0.75 m to 1.5–2.5 m, and the radius of curvature of the upper 90° bend connecting to the dust collector inlet is increased from approximately 0.85 m to 1.25–2.0 m. The cross-sectional shape of the bends is also appropriately optimized to reduce the generation of secondary flow. After these modifications, compared with the baseline (case 0) without modifications, the simulation results of different schemes show improved flow field uniformity within the pipe in all schemes with increased curvature radii. The separated vortex region at the bend is significantly reduced or even eliminated, the temperature gradient on the pipe cross-section is reduced, and local overheating is alleviated. Among these, the scheme in case 4 (specific curvature combination) shows the best effect, with the most uniform temperature field and almost no dead zones within the bend, indicating that a reasonable curvature amplification combination can effectively eliminate the backflow zone and enhance the consistency of heat transfer. Furthermore, with the increase in the curvature of the bend, the maximum shear stress on the wall surface is significantly reduced: from approximately 1.26 Pa in the original case 0 to approximately 1.07 Pa in case 4, and the range of the high shear stress region shrinks synchronously. The local high stress on the wall surface caused by "sharp bend scouring" is alleviated, which helps to reduce the risk of pipe wall wear and fatigue failure. The pressure loss inside the pipe is also significantly reduced: the maximum pressure inside the pipe in the baseline (case 0) is approximately 297 Pa, while the optimized schemes generally reduce it to approximately 214-221 Pa, indicating that the high-pressure impact zone on the outside of the bend and the low-pressure separation zone on the inside are both weakened, the pressure field distribution tends to be more uniform, and the total pressure drop is reduced by more than 25%. This means that the power consumption load of the dust removal system's fan is reduced, and the energy-saving effect is significant. In terms of the velocity field, the high-speed jet in the optimized pipe is suppressed, the local maximum flow velocity of up to 34.4 m / s in the baseline (case 0) is reduced to about 30 m / s, and the range of the high-speed zone is reduced, and the streamline distribution is smoother. The more uniform velocity distribution not only reduces kinetic energy loss, but also reduces the risk of flow-induced vibration and noise. It is worth noting that the effect of increasing the curvature of the bend on the turbulence intensity is non-monotonic: moderately increasing the curvature (as in cases 1 and 2) can reduce the overall turbulent kinetic energy within the system, but excessively large curvature combinations (cases 3 and 4) may induce new shear layer instability, causing a rebound in local turbulent kinetic energy. Therefore, in practical engineering implementation, it is necessary to comprehensively consider factors such as pressure drop, wall stress, and flow stability to select an optimized combination of curvature parameters. The optimized scheme finally determined in this invention reduces energy consumption while ensuring a stable flow field and avoiding new turbulence problems. Simulations of the optimized dust removal system show that the maximum shear stress on the wall, the peak local pressure in the pipe, and the number of uncaptured fiber particles in the exhaust gas all decrease significantly, the uniformity of the flow field and temperature field is greatly improved, and the energy efficiency and fiber recovery performance of the entire fiber drawing exhaust gas treatment system are synergistically improved.

[0019] The present invention provides a method for recycling and reusing microfiber glass wool waste. Through wet pretreatment, melt phase separation, and composition recovery, impurities are removed and the composition is restored, achieving high-quality regeneration of glass wool waste. Furthermore, CFD simulation can be used to optimize the dust removal pipeline, thereby improving energy efficiency during the regeneration process. This invention specifically addresses the two key bottlenecks of impurity purification and flow field optimization, constructing a new process that combines resource recycling and clean production, significantly improving the quality and efficiency of glass wool waste recycling. The beneficial effects of this invention are mainly reflected in the following aspects: (1) Efficient separation of impurities: This invention uses a wet pretreatment process combined with high-temperature melting and phase separation to fully separate calcium and sulfur impurities, such as calcium sulfate, from glass wool waste. After the upper layer of enriched Ca and S impurity slag is removed, the content of sulfur and other impurities in the recycled glass melt is significantly reduced, avoiding problems such as bubbles and inclusions caused by sulfur decomposition when directly melting waste, thus ensuring the quality of recycled glass from the source.

[0020] (2) Composition Restoration and Fiber Applicability: Through composition restoration compensation and secondary melting, the recycled glass block obtained by this invention has a chemical composition highly consistent with the original finished glass. The main components of the recycled glass (SiO2, Na2O, CaO, etc.) are restored to the normal formula range, and XRD detection shows an amorphous structure, indicating that the phase and composition of the recycled material are the same as those of standard glass, and it has the adaptability to be directly used in fiber drawing process. The high-temperature viscosity-temperature curve of the recycled glass is close to that of the original waste glass and slightly lower, which means that its viscosity is slightly lower at the same fiber forming temperature range. It is expected that the furnace temperature can be appropriately reduced while ensuring stable fiber forming, thereby achieving the effect of saving energy.

[0021] (3) Flow field optimization and energy efficiency improvement: This invention uses CFD simulation to identify problematic areas such as local high flow velocity, high shear, and backflow in the dust removal system, and optimizes the pipe structure (especially the curvature of bends) accordingly. After optimization, the flow in the dust removal pipe is more stable, the maximum shear stress on the wall and the pressure drop in the pipe are significantly reduced (by more than 20%), and the airflow distribution and temperature field tend to be more uniform. This reduces the ineffective energy loss caused by turbulence and local hot spots, and improves the system's thermal energy utilization efficiency. At the same time, airflow optimization reduces the probability of the tail fiber being carried out by the airflow, and the cyclone dust collector's collection efficiency for fine fibers is improved, further reducing the generation of fiber waste.

[0022] (4) Cleaner Production Synergistic Benefits: This invention combines waste recycling with source emission reduction optimization, achieving a cleaner improvement across the entire glass wool production process. On the one hand, the recycling process transforms accumulated glass wool scraps into reusable high-quality raw materials, turning waste into treasure, reducing the consumption of virgin raw materials, and lowering waste treatment costs. On the other hand, process optimization reduces energy consumption and pollutant emissions in the exhaust gas, improving the production environment and equipment reliability. The synergistic effect of these two aspects constructs a closed-loop mechanism from reducing new waste generation to recycling existing waste, improving the resource utilization efficiency and environmental friendliness of microfiber glass wool production, and possessing significant economic and social value and broad application prospects.

[0023] (5) Deep Synergistic Effect of Material Regeneration and Equipment Optimization: The method of this invention is not merely a simple superposition of regeneration process and dust removal technology, but rather an inherent technological dependence between the two. Because the viscosity of the glass melt regenerated by this invention is slightly lower than that of the virgin glass in the fiber-forming temperature range, the drawn regenerated fibers are more susceptible to shear damage and thermal adhesion in high-temperature flue gas. If conventional dust removal pipes (with high shear zones and reflux hot spots) are used, these highly sensitive regenerated fibers will break or adhere to the pipe wall in large quantities, leading to a sharp decline in the recovery rate. The specific "low-shear, no-thermal-retention" flow field (with a maximum shear stress reduction of over 15%) constructed by this invention through CFD optimization is precisely designed to adapt to the specific rheological characteristics of regenerated glass fibers. Experiments and simulations show that when only the regeneration process is used without matching optimized pipes, only existing waste can be recycled; however, when both are used synergistically, the effective recovery rate of the tail fiber can be significantly improved. This synergistic design of "adapting the flow field to the material" overcomes the bottleneck of the difficulty in industrial application of low-viscosity regenerated glass.

[0024] The various terms and phrases used in this invention have their general meanings known to those skilled in the art. Attached Figure Description

[0025] Figure 1 A simplified flowchart of the recycling method for microfiber glass wool waste.

[0026] Figure 2 The phase composition and elemental composition analysis results of W0, W1, W1-2 and W1-1 are shown in (a) for the phase composition comparison of W0 and W1, (b) for the elemental composition comparison of W0 and W1, and (c) for the phase composition comparison of W1-1 and W1-2.

[0027] Figure 3 The results of measurements of viscosity, shear force, rotational speed, torque, and shear rate of raw waste glass.

[0028] Figure 4The results of measurements of viscosity, shear force, rotational speed, torque, and shear rate of recycled glass.

[0029] Figure 5 XRD and phase composition comparisons of recycled glass blocks, finished glass blocks, and glass wool waste. The left image shows the XRD comparison of recycled glass blocks, finished glass blocks, and glass wool waste, while the right image shows the phase composition comparison of finished glass blocks and recycled glass blocks.

[0030] Figure 6 Comparison of the number of air bubbles in recycled glass blocks and finished glass blocks.

[0031] Figure 7 : Velocity distribution and dynamic pressure distribution under the operation of all equipment, where (a) velocity distribution under the operation of all equipment, and (b) dynamic pressure distribution under the operation of all equipment.

[0032] Figure 8 Shear stress distribution on the surface of the cyclone dust collector and pipelines under full equipment operation.

[0033] Figure 9 : Velocity distribution and dynamic pressure distribution under single equipment operation, wherein (a) velocity distribution under single equipment operation, and (b) dynamic pressure distribution under single equipment operation.

[0034] Figure 10 Shear stress distribution on the surface of cyclone dust collectors and pipelines under single-equipment operation.

[0035] Figure 11 : Turbulence intensity and turbulent kinetic energy under the operation of all equipment, and turbulence intensity and turbulence kinetic energy under the operation of a single equipment, wherein (a) turbulence intensity under the operation of all equipment, (b) turbulence kinetic energy under the operation of all equipment, (c) turbulence intensity under the operation of a single equipment, and (d) turbulence kinetic energy under the operation of a single equipment.

[0036] Figure 12 Temperature distribution and total pressure distribution under full equipment operation, where (a) temperature distribution under full equipment operation and (b) total pressure distribution under full equipment operation.

[0037] Figure 13 : Particle streamline diagram and particle velocity vector diagram under full equipment operation, wherein (a) particle streamline diagram under full equipment operation, and (b) particle velocity vector diagram under full equipment operation.

[0038] Figure 14 Temperature distribution and total pressure distribution under single-device operation, where (a) temperature distribution under single-device operation and (b) total pressure distribution under single-device operation.

[0039] Figure 15: Particle streamline diagram, particle velocity vector diagram and schematic diagram of glass wool loss in the dust removal system under single equipment operation, wherein (a) particle streamline diagram under single equipment operation, (b) particle velocity vector diagram under single equipment operation, and (c) schematic diagram of glass wool loss in the dust removal system.

[0040] Figure 16 Temperature simulation mapping for cases 1-4.

[0041] Figure 17 Temperature shear stress in cases 1-4.

[0042] Figure 18 Temperature and pressure in cases 1-4.

[0043] Figure 19 Temperature flow rate in cases 1-4.

[0044] Figure 20 Temperature-turbulent kinetic energy in cases 1-4.

[0045] Figure 21 The maximum wall shear stress, maximum pressure in the pipeline, maximum velocity in the flow line, and maximum turbulent kinetic energy in the cyclone separator are given for cases 0-4, where (a) is the maximum wall shear stress, (b) is the maximum pressure in the pipeline, (c) is the maximum velocity in the flow line, and (d) is the maximum turbulent kinetic energy in the cyclone separator. Detailed Implementation

[0046] The present invention will be further described below with reference to embodiments. However, the scope of the present invention is not limited to the following embodiments. Those skilled in the art will understand that various changes and modifications can be made to the present invention without departing from the spirit and scope thereof.

[0047] Unless otherwise specified, the instruments, reagents, and materials used in the following embodiments are all conventional instruments, reagents, and materials already available in the prior art and can be obtained through legitimate commercial channels. Unless otherwise specified, the experimental methods and detection methods used in the following embodiments are all conventional experimental methods and detection methods already available in the prior art.

[0048] Example 1: Recycling of waste microfiber glass wool A simplified flowchart of the recycling method for microfiber glass wool waste is shown below. Figure 1 As shown, the steps are as follows: (1) Wet pretreatment Microfiber glass wool waste (W0) is added to water and stirred to fully wet and initially disperse it, so that soluble calcium and sulfur impurities on the surface and inside of the microfiber glass wool waste dissolve out. Then, it is subjected to ultrasonic treatment to loosen the fiber bundles and promote the removal of impurities. Then, it is filtered, and the filter residue is wet glass fiber. After drying, the pretreated glass fiber (W1) is obtained. Wet pretreatment can destroy the bonding layer on the fiber surface and remove flux ions, which can significantly reduce the content of Ca and S impurities in microfiber glass wool waste, which is beneficial to the subsequent liquid-liquid immiscible phase separation of the high-temperature melt.

[0049] Specifically, waste fiber material (containing a small amount of sand and dust and resin binder residue) collected from a microfiber glass wool production line was used as raw material W0. 5 kg of W0 was placed in a washing tank equipped with a stirrer, and 25 L of deionized water was added (liquid-to-solid ratio 5:1). Mechanical stirring was started and the mixture was stirred at 300 rpm for 30 minutes to fully impregnate and initially disperse the glass fibers. Subsequently, the slurry was treated with ultrasound at a power of 500 W and a frequency of 25 kHz for 20 minutes to loosen the fiber bundles and promote impurity removal. After stirring-ultrasound treatment, the slurry was filtered through an 80-mesh filter. The filtrate was a pale yellow clear liquid, and the filter residue was wet glass fibers. The filter residue was repeatedly washed with deionized water until the filtrate had no obvious color. The filter residue was then dried in an 80℃ hot air oven to constant weight, yielding approximately 3.8 kg of glass fiber sample W1.

[0050] Visually, W1 appears as clean, white, cotton-like material, clearly distinguishable from the yellow appearance of waste WO. Chemical analysis of WO and W1 revealed that WO's sulfur content (as SO3) was 9.6%, while W1's sulfur content decreased to 1.8%; WO's calcium content (as CaO) was approximately 15%, while W1's calcium content decreased to approximately 10%. This indicates that wet pretreatment removed a large amount of soluble sulfur-containing salts and some alkaline earth metal impurities, but microscopic observation revealed the potential presence of small amounts of fine inorganic particles (such as calcium salt crystals).

[0051] (2) High-temperature melting separation The glass fiber (W1) obtained through the above wet pretreatment is mixed with an appropriate amount of glass raw materials, such as quartz sand, soda ash, feldspar, limestone, borax, or alumina powder, to restore the content of the main components of the mixture (including SiO2, Al2O3, MgO, Na2O, and K2O) to the content of the main components of the finished glass (SiO2 content of 67%–69%, Al2O3 content of 2.5%–3.5%, MgO content of 2.5%–3.5%, Na2O content of 17%–19%, and K2O content of 1%–2.5%). The contents are the same or similar to supplement the silicon and alkali metal components and adjust the CaO / MgO ratio; heat to 1300-1500℃ and hold for 1-2 hours to melt the material fully and cause high-temperature phase separation: based on the interfacial tension difference induced by pretreatment, the Ca and S impurities in the glass melt form independent impurity phases (slag phase or precipitate phase) that are immiscible with the silicate melt phase and aggregate and precipitate; cool, and two phases are generated, the upper layer is a milky white solid (W1-2), and the lower layer is a transparent glass block (W1-1); separate the two phases and retain the lower transparent glass block (W2).

[0052] Specifically, 3.8 kg of glass fiber 1 (W1) obtained through wet pretreatment was mixed with an appropriate amount of glass raw materials to restore the content of the main components of the mixture (including SiO2, Al2O3, MgO, Na2O, and K2O) to the same level as the main components of the finished glass (approximately 68% SiO2, 18% Na2O, 3% MgO, 3% Al2O3, and 2% K2O). The mixture was then placed in a high-platinum crucible and heated to 1400°C in an electric furnace for 1 hour. During this melting process, a unique "interface-induced immiscible phase separation" phenomenon was observed: because the preceding wet ultrasonic pretreatment effectively destroyed the high-energy binder layer on the surface of the waste fiber and removed the soluble trace ions that acted as fluxing emulsifiers, impurities such as calcium sulfate (CaSO4) in the melt could not form a homogeneous solid solution or microemulsion as in the treatment of virgin waste. Conversely, driven by the surface tension gradient, the impurity phase significantly agglomerates and undergoes liquid-liquid immiscibility separation with the silicate main phase, eventually spontaneously floating upwards due to the density difference (the impurity phase has a lower density). It is important to note that if the waste is directly melted without wet pretreatment (wet deagglomeration and ultrasonic exfoliation), the impurities will remain in the glass phase as microbubbles or dispersed microcrystals, failing to form a clear macroscopic stratification interface. Subsequently, the molten liquid, along with the crucible, is transferred to a muffle furnace for annealing and cooling, slowly cooling to room temperature, resulting in the formation of upper and lower phase stratification, as shown below. Figure 1As shown, observations revealed that the cooled glass block exhibited a clear 'two-phase structure': the upper 1 / 3 of the thickness consisted of a milky white, porous, brittle solid (enriched Ca and S separated phases) (W1-2), while the lower 2 / 3 consisted of a transparent, homogeneous glass block (W1-1). The upper impurities were removed, and the lower transparent glass block was retained, resulting in the fully impurity-removed sample W2 (W2).

[0053] Chemical composition analysis of W2 yielded the following results: SiO2, 68.0%; Na2O, 13.2%; CaO, 8.5%; MgO, 2.9%; Al2O3, 2.8%; K2O, 1.1%; Fe2O3, 0.3%; SO3, 0.3%; the remainder being trace impurities. Compared to the standard formulation of the finished glass from this production line (approximately 68% SiO2, 18% Na2O, 5% CaO, 3% MgO, 3% Al2O3, 2% K2O, <1% Fe2O3, <0.1% SO3), the main differences in W2 composition are: slightly lower Na2O and higher CaO and SO3. The decrease in Na2O is attributed to some Na elements entering the upper sulfate phase during the melting and phase separation process (upper impurity analysis showed approximately 16% Na2O). The higher CaO and residual SO3 indicate that a small amount of sulfate was not completely separated.

[0054] The phase composition and elemental composition of glass wool waste (W0), W1, W1-2, and W1-1 (i.e., W2) were analyzed, and the results are as follows: Figure 2 As shown in the figure, chemical composition analysis indicates that the content of harmful impurities sulfur and calcium in sample W2 has been significantly reduced compared to W1. For example, the SO3 content has decreased from approximately 1.75% to below 0.3%, and the CaO content has decreased to approximately 8%. Correspondingly, most of the sulfur and excess calcium are enriched in the removed W1-2 slag, whose main components are sulfates such as CaSO4 and a small amount of unmelted quartz and other impurities. It is evident that efficient separation of calcium and sulfur impurities from glass wool waste has been achieved through wet pretreatment combined with high-temperature melting.

[0055] (3) Composition recovery and remelting The transparent glass block (W2) obtained by high-temperature melting and separation is mixed with an appropriate amount of glass raw materials, such as quartz sand, soda ash, feldspar, limestone, borax, or alumina powder. By adding raw materials, the content of the main components of the mixture (including SiO2, Al2O3, MgO, Na2O, and K2O) is restored to the same or similar content as the main components of the finished glass. A clarifying agent can be added to the mixture to promote the subsequent removal of bubbles. The clarifying agent is composed of sodium nitrate and sodium sulfate. The mixture is then fully melted and homogenized, and cooled to obtain the recycled glass block.

[0056] Specifically, 1.0 kg of W2 was added to another platinum crucible. Based on the composition analysis results of step (2) and the comparison results with the standard proportion of the finished glass, the amount of raw materials to be added was calculated. Glass raw materials such as soda ash and quartz sand were added to restore the content of the main components of the mixture (including SiO2, Al2O3, MgO, Na2O and K2O) to the same level as the main components of the finished glass (approximately 68% SiO2, approximately 18% Na2O, approximately 3% MgO, approximately 3% Al2O3, and approximately 2% K2O). An appropriate amount of refining clarifying agent (0.2 kg of sodium nitrate and 0.1 kg of sodium sulfate) was added to promote the subsequent removal of bubbles. The crucible was placed in an electric melting furnace, heated to 1550℃ for melting for 30 minutes, the temperature was increased to 1600℃ for clarification for 15 minutes, and then lowered to 1200℃ for homogenization for 30 minutes. Subsequently, it was cast into shape and annealed and cooled to obtain a recycled glass block sample.

[0057] XRD analysis of the recycled glass blocks revealed no obvious crystalline phase diffraction peaks, only broad diffuse scattering peaks consistent with standard glass, indicating that the recycled glass is a homogeneous amorphous state without residual impurities such as sulfate crystals. Chemical composition analysis showed the following results: SiO2, 67.5%; Na2O, 17.8%; CaO, 5.1%; MgO, 3.2%; Al2O3, 3.0%; K2O, 1.3%; Fe2O3, 0.3%; SO3, 0.06%. The major oxides are very similar to those in the finished glass, with sulfur content reduced to below 0.1%. This demonstrates that through compositional recovery compensation and remelting, the waste material was successfully transformed into recycled glass that meets production requirements.

[0058] To evaluate the processing performance of recycled glass, the high-temperature viscosity characteristics of the recycled glass blocks were tested and compared with glass made directly from waste WO (obtained by direct melting and clarification without impurity removal, hereinafter referred to as original waste glass) and normal finished glass. The results are as follows: Figure 3 , Figure 4 As shown in the figure. The results indicate that the viscosity of recycled glass in the fiber-forming temperature range of 1100–1200℃ is very close to that of finished glass (both are within 10). 3 The viscosity of recycled glass (on the order of Pa·s) is slightly lower than that of virgin waste glass. This means that the viscosity required for fiber drawing can be achieved at a slightly lower temperature, which helps reduce melting energy consumption. At the same time, the slope of the viscosity-temperature curve of recycled glass is comparable to that of the finished product, indicating that its viscosity is similarly sensitive to temperature changes, suggesting that the temperature control strategy in the fiber drawing process does not require major adjustments. Therefore, recycled glass blocks are perfectly suitable for the existing fiber drawing process of microfiber glass wool and can directly replace a portion of the virgin batch material in production.

[0059] XRD comparison and phase composition comparison of recycled glass blocks, finished glass blocks, and glass wool waste Figure 5As shown, no obvious crystalline impurity peaks appeared in the XRD diffraction pattern of the recycled glass block, indicating that impurity phases such as sulfates have been effectively removed. The recycled glass is mainly composed of an amorphous glass phase, maintaining the same amorphous structural characteristics as the finished glass. Furthermore, the content of major oxides in the recycled glass block is highly similar to that of the original finished glass block; for example, SiO2 is approximately 68%, Na2O approximately 18%, CaO approximately 5%, MgO and Al2O3 approximately 3% each, and the contents of trace components such as K2O and Fe2O3 are also basically at the same level. It is evident that through compositional compensation and remelting, the waste glass formulation has been restored, bringing the chemical composition of the recycled glass back to the range of the finished glass formulation.

[0060] To understand the bubble situation within the glass block, the number of bubbles was analyzed, and the results are as follows: Figure 6 As shown, the number of bubbles in recycled glass and finished glass is similar.

[0061] Example 2: CFD Analysis and Structural Optimization of Dust Collection Ducts Using the recycled glass blocks prepared in Example 1 as raw materials, glass fiber wool can be prepared through conventional processes. However, the exhaust gas dust removal system of the drawing section in the existing microfiber glass wool production line is not very effective. This example performs CFD analysis and structural optimization on it. Specifically, a CFD simulation study is conducted on the exhaust gas dust removal pipeline of the drawing system of a glass wool factory, and an optimization scheme is given based on the simulation results.

[0062] The dust removal system consists of two parallel wire drawing production lines whose exhaust gases are drawn into a cyclone dust collector. The outlet of each production line is connected to the inlet cylinder of the dust collector through a 90° vertical bend pipe, and a 180° turnaround channel is provided below to guide the exhaust port of the dust collector to the inlet of the induced draft fan.

[0063] First, a full-size 3D model was created using the computational fluid dynamics software Fluent, including: a vertical bend (upper bend) from the exhaust gas outlet of the wire drawing furnace to the inlet of the cyclone dust collector; the cyclone dust collector body (diameter 0.5 m, height 1.5 m, volute inlet size as actual); and a return bend (lower bend) from the top outlet of the cyclone dust collector to the fan inlet. After meshing the model, boundary conditions were applied: a total inlet flow rate of 5000 m³ / h for the exhaust gas from both wire drawing furnaces. 3 / h, temperature 300℃, particulate matter concentration 2 g / m³ 3 (Fiber particle size distribution 0.5–5 μm); the discharge resistance at the lower ash outlet of the cyclone dust collector is set according to the actual load, and the air outlet connection fan is set to a fixed pressure boundary (0 Pa gauge pressure). The flow field is simulated using the standard k-Ω SST turbulence model, and the DPM model is used to track the fiber particle trajectory to calculate the airflow velocity, pressure, temperature, and particle distribution in the pipeline under steady-state conditions.

[0064] The results of the simulated baseline operating condition (full operating conditions of both production lines) are as follows: Figure 7 , Figure 8 , Figure 9 , Figure 10 and Figure 11 As shown (Note: Full equipment operation refers to both production lines running; single equipment operation refers to a single piece of equipment running), at the T-shaped connection at the cyclone dust collector inlet and in the vertical downflow section, the airflow velocity increases sharply and changes direction drastically, forming obvious jets and vortices. The maximum flow velocity occurs in one of the inlet bends, approximately 34 m / s. The shear stress on the wall in this area also reaches a peak of approximately 1.26 Pa, far exceeding the average level of the pipeline, indicating a strong scouring effect. Above the interior of the cyclone dust collector, there is also a region of high-intensity turbulence caused by airflow rotation, with a maximum turbulent kinetic energy of approximately 5 m³ / s. 2 / s 2 .

[0065] like Figure 12 As shown, these uneven flow phenomena lead to localized heat accumulation: the temperature near the dust collector inlet was measured to be more than 20°C higher than the system average temperature, and molten, deformed fibrous flocs were observed adhering to the pipe wall at this location, indicating that the high-temperature airflow had caused some of the tail fibers to adhere and melt. On the other hand, simulations showed the presence of low-speed backflow vortices in the inner region of the cyclone dust collector outlet bend, corresponding to a stagnant area where fibers may deposit. Figure 13 , Figure 14 and Figure 15 As shown, the DPM trajectory results of fiber particles indicate that some fine fibers are directly ejected at the top outlet of the cyclone dust collector by the high-speed airflow, and the cyclone's collection efficiency for these fibers is poor.

[0066] For the identified problem areas, the following optimization schemes are proposed for the dust removal ducts: Increase the curvature radius of the bends and optimize the flow field design. The two upper bends (90° bends perpendicular to the cyclone inlet) will have their bending radii increased from the original 0.85 m to 1.25 m, and the cross-section will be changed from a circle to a combination of square and circle with a slight transition section to smoothly distribute the airflow. The lower bend (180° bend at the cyclone outlet) will have its radius increased from the original 0.75 m to 1.5 m, and guide vanes will be added to the outer wall of the bends to guide the airflow to adhere to the wall and change direction. Based on this optimization, further optimizations will be made considering the special rheological properties of recycled glass fiber (see below). There are four optimization schemes (the original scheme is case 0): Case 1, Case 2, Case 3, and Case 4. The specific optimization schemes for Cases 1 to 4 are as follows: Case 1: The upper curvature radius of the upper bend is 1.25 m (approximately 2.5 times the pipe diameter), the lower curvature radius of the upper bend is 1.00 m (approximately 2.0 times the pipe diameter), and the lower curvature radius of the lower bend is 1.50 m (approximately 3.0 times the pipe diameter).

[0067] Case 2: The upper curvature radius of the upper bend is 2.00 m (approximately 4.0 times the pipe diameter), the lower curvature radius of the upper bend is 1.50 m (approximately 3.0 times the pipe diameter), and the lower curvature radius of the lower bend is 2.00 m (approximately 4.0 times the pipe diameter).

[0068] Case 3: The upper curvature radius of the upper bend is 2.50 m (approximately 5.0 times the pipe diameter), the lower curvature radius of the upper bend is 2.00 m (approximately 4.0 times the pipe diameter), and the lower curvature radius of the lower bend is 2.50 m (approximately 5.0 times the pipe diameter).

[0069] Case 4: The upper curvature radius of the upper bend is 2.00 m (approximately 4.0 times the pipe diameter), the lower curvature radius of the upper bend is 1.50 m (approximately 3.0 times the pipe diameter), and the lower curvature radius of the lower bend is 1.50 m (approximately 3.0 times the pipe diameter).

[0070] The CFD calculations were performed again using the optimized geometric model, and the resulting flow field was significantly improved compared to the original model: the temperature simulation mappings for cases 1-4 are as follows. Figure 16 As shown, the shear stress is as follows Figure 17 As shown, the pressure is as Figure 18 As shown, the flow velocity is as follows Figure 19 As shown, turbulent kinetic energy is as follows Figure 20 As shown in Figure 19; it can be seen from Figure 19 that the maximum flow velocity at the upper bend drops to about 29 m / s, according to Figure 17 The peak wall shear stress was reduced to 1.17 Pa, and the high shear stress region was reduced from the entire outer arc surface to a small area confined to the front end of the guide vane; the turbulence intensity at the confluence of the two airflows at the cyclone inlet decreased by about 5%, according to Figure 16 It can be seen that the localized overheating caused by the convergence of the two hot air streams has disappeared, and the temperature distribution is more uniform. Figure 20 It can be seen that at the lower bend, due to the increased radius of curvature and the effect of flow guiding measures, the original separation vortex zone is greatly weakened, and backflow stagnation almost no longer occurs within the bend, allowing the airflow to smoothly turn while adhering closely to the pipe wall. From Figure 18 The pressure readings in the pipeline show a reduction in pressure loss, with calculations indicating a decrease in total pressure drop of approximately 28%, corresponding to a saving of about 5 kW in induced draft fan power. More importantly, the fate of fiber particles in the exhaust gas has changed positively: DPM statistics show that over 97% of the fibers entering the cyclone are captured in the cyclone ash hopper, while the proportion directly escaping with the exhaust gas has decreased from 5% to below 1%. This demonstrates that the optimized dust collection system significantly improves the fiber capture rate.

[0071] Maximum wall shear stress, maximum pressure in the pipeline, maximum velocity in the conveyor line, and maximum turbulent kinetic energy in the cyclone separator for cases 0-4 are as follows: Figure 21 As shown. From Figure 21 The changes in parameters after the modification of the dust removal system reveal that, based on the above optimizations, this embodiment further explores the coupling effect of different combinations of pipe curvature on wall shear stress and secondary turbulent kinetic energy. This is a key consideration based on the special rheological properties of recycled glass fiber: as shown in the aforementioned viscosity test results (see...). Figure 3 and Figure 4 Recycled glass has a slightly lower viscosity at high temperatures than virgin glass, meaning that recycled fibers are more thermally sensitive and brittle during pneumatic transport, and are extremely sensitive to shear forces. While conventional large curvature designs can reduce pressure drop, simulations show (comparing cases 3 and 4) that blindly increasing the curvature radius can induce secondary flow instability at the center of the pipe, leading to a rise in local turbulent kinetic energy (Figure 21(d) shows the rise in turbulent kinetic energy in case 3), which can cause fiber flutter and breakage. Considering all factors, this embodiment ultimately selects case 4 as the only recommended implementation. That is, the upper bend has a curvature radius of 2.0 m (approximately 4 times the pipe diameter), and the lower bend has a curvature radius of 1.5 m (approximately 3 times the pipe diameter). This specific curvature combination creates a low-shear, low-turbulence window, strictly controlling the maximum wall shear stress below 1.07 Pa (Figure 21(a)), effectively preventing secondary breakage and pipe wall adhesion of low-viscosity recycled fibers during transport. Therefore, the scheme in case 4 is not a simple parameter rotation, but a fluid-structure interaction matching design tailored to the material properties of the recycled fibers.

[0072] The above embodiments demonstrate that the proposed method for synergistic optimization of glass wool waste recycling and CFD treatment is feasible. The recycled glass blocks meet all production requirements, and the optimized pipeline dust collection system significantly improves the tail fiber recovery rate and thermal energy utilization efficiency. This method can be used for the technical transformation of existing glass wool production lines and the clean production process design of new production lines, which is of great significance for achieving waste reduction and resource recycling in the glass fiber industry.

[0073] The above embodiments are provided to those skilled in the art to fully disclose and describe how the claimed implementations can be carried out and used, and are not intended to limit the scope of the disclosure herein. Modifications that will be obvious to those skilled in the art will be within the scope of the appended claims.

Claims

1. A method for recycling and reusing microfiber glass wool waste, characterized in that, Includes the following steps: (1) Wet pretreatment: The microfiber glass wool waste is put into water, stirred to fully soak and initially disperse it; then ultrasonic treatment is carried out. Filtration, drying of the filter residue, yielding glass fiber; (2) High-temperature melting and separation: The glass fiber obtained by the above wet pretreatment is mixed with glass raw materials to restore the content of the main components of the mixture to the same or similar content as the main components of the finished glass; heated to 1300-1500℃ and kept at the temperature for 1-2 hours to melt; cooled to produce upper and lower phases, the two phases are separated, and the lower transparent glass block is retained; (3) Composition recovery and remelting: The transparent glass block obtained by high-temperature melting and separation is mixed with glass raw materials. By adding raw materials, the content of the main components of the mixture is restored to the same or similar to the content of the main components of the finished glass. The mixture is fully melted and homogenized, cooled, and a recycled glass block is obtained.

2. The method for recycling and reusing microfiber glass wool waste according to claim 1, characterized in that, It also includes the following steps: (4) Preparing glass fiber cotton: glass fiber cotton is prepared by using recycled glass blocks as raw materials, wherein the glass fiber cotton production line drawing section is equipped with a tail gas dust removal system; the tail gas dust removal system includes a cyclone dust collector, the inlet of the cyclone dust collector is connected to the tail gas outlet through a vertical bend pipe, and the air outlet at the top of the cyclone dust collector is connected to the fan inlet through a return bend pipe.

3. The method for recycling and reusing microfiber glass wool waste according to claim 2, characterized in that: The radius of curvature of the vertical bend is set to 4 times the pipe diameter, and the radius of curvature of the return bend is set to 3 times the pipe diameter.

4. The method for recycling and reusing microfiber glass wool waste according to claim 2, characterized in that: A guide vane is installed on the outside of the vertical bend and / or return bend.

5. The method for recycling and reusing microfiber glass wool waste according to claim 1, characterized in that: In step (1), the parameters for ultrasonic treatment are: power 300-700 W, frequency 15-40 kHz, and treatment time 10-30 minutes.

6. The method for recycling and reusing microfiber glass wool waste according to claim 1, characterized in that: In steps (2) and (3), the glass raw materials are selected from any one or more of the following: quartz sand, soda ash, feldspar, limestone, borax, or alumina powder.

7. The method for recycling and reusing microfiber glass wool waste according to claim 1, characterized in that: In steps (2) and (3), after adding glass raw materials, the content of SiO2 in the mixture is 67% to 69%, the content of Al2O3 is 2.5% to 3.5%, the content of MgO is 2.5% to 3.5%, the content of Na2O is 17% to 19%, and the content of K2O is 1% to 2.5%.

8. The method for recycling and reusing microfiber glass wool waste according to claim 7, characterized in that: The mixture contains 68% SiO2, 3% Al2O3, 3% MgO, 18% Na2O, and 2% K2O.

9. The method for recycling and reusing microfiber glass wool waste according to claim 1, characterized in that: In step (2), the temperature is raised to 1400°C and kept at that temperature for 1 hour to melt the metal. In step (3), the parameters for melting and homogenizing are: heating to 1550℃ for 30 minutes, raising the temperature to 1600℃ for clarification for 15 minutes, and then lowering the temperature to 1200℃ for homogenization for 30 minutes.

10. The method for recycling and reusing microfiber glass wool waste according to claim 1, characterized in that: In step (3), a clarifying agent is added to the mixture.

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