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Xu M, Yang J, Ji H, Wu Y, Li J, Di J, Meng X, Jiang H, Lu Q. Recovering high-quality glass fibers from end-of-life wind turbine blades through swelling-assisted low-temperature pyrolysis. WASTE MANAGEMENT (NEW YORK, N.Y.) 2024; 187:179-187. [PMID: 39038429 DOI: 10.1016/j.wasman.2024.07.020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2024] [Revised: 07/14/2024] [Accepted: 07/18/2024] [Indexed: 07/24/2024]
Abstract
The recycling of end-of-life wind turbine blades has become a global environmental challenge driven by the rapid growth of wind power. Pyrolysis is a promising method for recovering glass fibers from these discarded blades, but traditional pyrolysis is often operated at high temperatures, which degrades the mechanical properties of recovered fibers. To address this issue, a swelling-assisted pyrolysis method was proposed to recover high-quality glass fibers from end-of-life wind turbine blades at low temperatures. The results confirmed that the decomposition of the resin matrix within the blade was significantly promoted at low temperatures in the swelling-assisted pyrolysis process, achieving a resin decomposition ratio of 76.8 % at 350 °C. This improvement was attributed to enhanced heat transfer and co-pyrolysis with acetic acid. Swelling could physically disrupt the cross-linked structure of the blade, creating a more porous and layered structure, thereby enhancing heat transfer during the pyrolysis process. Simultaneously, the co-pyrolysis with acetic acid could generate hydrogen radicals, which promoted the cracking of macromolecular oligomers into lighter products or gaseous alkanes. Consequently, the formation of pyrolysis char within the solid pyrolysis product was reduced, shortening the oxidation duration to 30 min. In comparison to traditional pyrolysis, the swelling-assisted pyrolysis process effectively suppressed the diffusion of surface defects over the recovered fibers, leading to promising improvements in their flexibility, elasticity, and mechanical properties, with tensile strength notably increased by 27.5 %. These findings provided valuable insights into recovering high-quality glass fibers from end-of-life wind turbine blades.
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Affiliation(s)
- Mingxin Xu
- National Engineering Research Center of New Energy Power Generation, North China Electric Power University, Beijing 102206, China
| | - Jie Yang
- National Engineering Research Center of New Energy Power Generation, North China Electric Power University, Beijing 102206, China
| | - Haiwen Ji
- National Engineering Research Center of New Energy Power Generation, North China Electric Power University, Beijing 102206, China
| | - Yachang Wu
- National Engineering Research Center of New Energy Power Generation, North China Electric Power University, Beijing 102206, China
| | - Jihong Li
- National Engineering Research Center of New Energy Power Generation, North China Electric Power University, Beijing 102206, China
| | - Jinyi Di
- National Engineering Research Center of New Energy Power Generation, North China Electric Power University, Beijing 102206, China
| | - Xiangxi Meng
- National Engineering Research Center of New Energy Power Generation, North China Electric Power University, Beijing 102206, China
| | - Hao Jiang
- National Engineering Research Center of New Energy Power Generation, North China Electric Power University, Beijing 102206, China
| | - Qiang Lu
- National Engineering Research Center of New Energy Power Generation, North China Electric Power University, Beijing 102206, China.
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Sola A, Rosa R, Ferrari AM. Environmental Impact of Fused Filament Fabrication: What Is Known from Life Cycle Assessment? Polymers (Basel) 2024; 16:1986. [PMID: 39065302 PMCID: PMC11281121 DOI: 10.3390/polym16141986] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2024] [Revised: 07/04/2024] [Accepted: 07/09/2024] [Indexed: 07/28/2024] Open
Abstract
This systematic review interrogates the literature to understand what is known about the environmental sustainability of fused filament fabrication, FFF (also known as fused deposition modeling, FDM), based on life cycle assessment (LCA) results. Since substantial energy demand is systematically addressed as one of the main reasons for ecological damage in FFF, mitigation strategies are often based on reducing the printing time (for example, adopting thicker layers) or the embodied energy per part (e.g., by nesting, which means by printing multiple parts in the same job). A key parameter is the infill degree, which can be adjusted to the application requirements while saving printing time/energy and feedstock material. The adoption of electricity from renewable resources is also expected to boost the sustainability of distributed manufacturing through FFF. Meanwhile, bio-based and recycled materials are being investigated as less impactful alternatives to conventional fossil fuel-based thermoplastic filaments.
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Affiliation(s)
- Antonella Sola
- Department of Sciences and Methods for Engineering (DISMI), University of Modena and Reggio Emilia, Via G. Amendola 2, 42122 Reggio Emilia, Italy; (R.R.); (A.M.F.)
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Papatheodorou A, Gavalas I, Ntenekou D, Karatza A. The Influence of Thermoplastic Composite Recycling on the Additive Manufacturing Process and In-Use Phase as Candidate Materials for Wearable Devices Applications. Polymers (Basel) 2023; 15:3775. [PMID: 37765629 PMCID: PMC10535287 DOI: 10.3390/polym15183775] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Revised: 08/30/2023] [Accepted: 08/31/2023] [Indexed: 09/29/2023] Open
Abstract
Fused filament fabrication (FFF) is a popular additive manufacturing (AM) method for creating thermoplastic parts with intricate geometrical designs. Pure thermoplastic materials utilized in FFF, whose polymeric matrix is reinforced with other materials, such as carbon fibers (CFs), introduce products with advanced mechanical properties. However, since not all of these materials are biodegradable, the need for recycling and reuse immediately emerges to address the significant problem of how to dispose of their waste. The proposed study evaluates the printability, surface morphology and in vitro toxicity of two thermoplastic-based composite materials commonly used in wearable device manufacturing to provide enhanced properties and functionalities, making them suitable for various applications in the field of wearable devices. Tritan Copolyester TX1501 with 7.3% chopped CFs (cCFs) and Polyamide 12 (PA12) with 8.6%cCFs and 7.5% iron Magnetic Nanoparticles (MNPs)-Fe4O3 were used in the discrete ascending cycles of recycling, focusing on the surface quality performance optimization of the printed parts. Through stereoscopy evaluation, under-extrusion, and over-extrusion defects, as well as non-uniform material flow, are assessed in order to first investigate the influence of various process parameters' application on the printing quality of each material and, second, to analyze the optimal value fluctuation of the printing parameters throughout the recycling cycles of the materials. The results indicate that after applying certain adjustments to the main printing parameter values, the examined recycled reinforced materials are still effectively 3D printed even after multiple cycles of recycling. A morphology examination using scanning electron microscope (SEM) revealed surface alterations, while a cytotoxicity assessment revealed the adverse effects of both materials in the form of cell viability and the release of proinflammatory cytokines in the cell culture medium.
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Affiliation(s)
- Alexandra Papatheodorou
- BioG3D P.C., 1 Lavriou Ave., Technological & Cultural Park of Lavrion, 19500 Lavrion, Greece
| | - Iakovos Gavalas
- BioG3D P.C., 1 Lavriou Ave., Technological & Cultural Park of Lavrion, 19500 Lavrion, Greece
| | - Despoina Ntenekou
- BioG3D P.C., 1 Lavriou Ave., Technological & Cultural Park of Lavrion, 19500 Lavrion, Greece
| | - Anna Karatza
- BioG3D P.C., 1 Lavriou Ave., Technological & Cultural Park of Lavrion, 19500 Lavrion, Greece
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Recycling of Thermoset Materials and Thermoset-Based Composites: Challenge and Opportunity. Polymers (Basel) 2022; 14:polym14194153. [PMID: 36236101 PMCID: PMC9570833 DOI: 10.3390/polym14194153] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2022] [Revised: 09/21/2022] [Accepted: 09/30/2022] [Indexed: 11/23/2022] Open
Abstract
Thermoset materials and their composites are characterized by a long life cycle with their main applications in aircrafts, wind turbines and constructions as insulating materials. Considering the importance of recovery and valorization of these materials at their end-of-life, avoiding landfilling, the interest concerning their recycling grows continuously. The thermoset materials and their composites, to be successfully recovered and valorized, must degrade their three-dimensional structures and recover the mono-oligomers and/or fillers. The thermoset materials could successfully degrade through thermal treatment at different temperatures (for example, above 1000 °C for incineration, ca. 500 °C for oxidation/combustion of organic constituents, etc.), chemical degradation by catalyst, irradiation with or without the presence of water, alcohol, etc., and mechanical recycling, obtaining fine particles that are useful as filler and/or reinforcement additives. Among these recycling methods, this mini-review focuses on the formulation and recovery method of innovative thermoset with in-build recyclability, i.e., materials having chemical links that could be degraded on-demand or containing dynamic covalent bonds to have re-processable and/or recyclable thermoset. This issue could be considered the future perspective in developing novel thermoset materials. The aim of this review is to get an overview of the state of the art in thermoset recycling and of the most commonly used thermoset composites, recovering valuable reinforcing fibers. Additionally, in this work, we also report not only known recycling routes for thermoset and thermoset-based composites, but also new and novel formulating strategies for producing thermosets with built-in recyclability, i.e., containing chemical-triggered on-demand links. This mini-review is also a valuable guide for educational purposes for students and specialized technicians in polymer production and recycling.
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Sun Y, Zheng Z, Wang Y, Yang B, Wang J, Mu W. PLA composites reinforced with rice residues or glass fiber—a review of mechanical properties, thermal properties, and biodegradation properties. JOURNAL OF POLYMER RESEARCH 2022. [DOI: 10.1007/s10965-022-03274-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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Carbon Fiber/PLA Recycled Composite. Polymers (Basel) 2022; 14:polym14112194. [PMID: 35683865 PMCID: PMC9182835 DOI: 10.3390/polym14112194] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Revised: 05/23/2022] [Accepted: 05/24/2022] [Indexed: 12/16/2022] Open
Abstract
Due exceptional properties such as its high-temperature resistance, mechanical characteristics, and relatively lower price, the demand for carbon fiber has been increasing over the past years. The widespread use of carbon-fiber-reinforced polymers or plastics (CFRP) has attracted many industries. However, on the other hand, the increasing demand for carbon fibers has created a waste recycling problem that must be overcome. In this context, increasing plastic waste from the new 3D printing technology has been increased, contributing to a greater need for recycling efforts. This research aims to produce a recycled composite made from different carbon fiber leftover resources to reinforce the increasing waste of Polylactic acid (PLA) as a promising solution to the growing demand for both materials. Two types of leftover carbon fiber waste from domestic industries are handled: carbon fiber waste (CF) and carbon fiber-reinforced composite (CFRP). Two strategies are adopted to produce the recycled composite material, mixing PLA waste with CF one time and with CFRP the second time. The recycled composites are tested under tensile test conditions to investigate the impact of the waste carbon reinforcement on PLA properties. Additionally, thermogravimetric analysis (TGA), X-ray diffraction (XRD), and Fourier-transformed infrared spectroscopy (FTIR) is carried out on composites to study their thermal properties.
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A Review of Polylactic Acid as a Replacement Material for Single-Use Laboratory Components. MATERIALS 2022; 15:ma15092989. [PMID: 35591324 PMCID: PMC9100125 DOI: 10.3390/ma15092989] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Revised: 04/04/2022] [Accepted: 04/18/2022] [Indexed: 02/04/2023]
Abstract
Every year, the EU emits 13.4 Mt of CO2 solely from plastic production, with 99% of all plastics being produced from fossil fuel sources, while those that are produced from renewable sources use food products as feedstocks. In 2019, 29 Mt of plastic waste was collected in Europe. It is estimated that 32% was recycled, 43% was incinerated and 25% was sent to landfill. It has been estimated that life-sciences (biology, medicine, etc.) alone create plastic waste of approximately 5.5 Mt/yr, the majority being disposed of by incineration. The vast majority of this plastic waste is made from fossil fuel sources, though there is a growing interest in the possible use of bioplastics as a viable alternative for single-use lab consumables, such as petri dishes, pipette tips, etc. However, to-date only limited bioplastic replacement examples exist. In this review, common polymers used for labware are discussed, along with examining the possibility of replacing these materials with bioplastics, specifically polylactic acid (PLA). The material properties of PLA are described, along with possible functional improvements dure to additives. Finally, the standards and benchmarks needed for assessing bioplastics produced for labware components are reviewed.
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Moslehi A, Ajji A, Heuzey M, Rahimizadeh A, Lessard L. Polylactic acid/recycled wind turbine glass fiber composites with enhanced mechanical properties and toughness. J Appl Polym Sci 2022. [DOI: 10.1002/app.51934] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Amirhosein Moslehi
- Département de génie chimique Polytechnique Montréal Montréal Quebec Canada
| | - Abdellah Ajji
- Département de génie chimique Polytechnique Montréal Montréal Quebec Canada
| | | | | | - Larry Lessard
- Department of Mechanical Engineering McGill University Montreal Quebec Canada
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Fabrication and Characterization of Fiber-Reinforced Composite Sandwich Structures Obtained by Fused Filament Fabrication Process. COATINGS 2021. [DOI: 10.3390/coatings11050601] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The application of fused filament fabrication processes is rapidly expanding in many domains such as aerospace, automotive, medical, and energy, mainly due to the flexibility of manufacturing structures with complex geometries in a short time. To improve the mechanical properties of lightweight sandwich structures, the polymer matrix can be strengthened with different materials, such as carbon fibers and glass fibers. In this study, fiber-reinforced composite sandwich structures were fabricated by FFF process and their mechanical properties were characterized. In order to conduct the mechanical tests for three-point bending, tensile strength, and impact behavior, two types of skins were produced from chopped carbon-fiber-reinforced skin using a core reinforced with chopped glass fiber at three infill densities of 100%, 60%, and 20%. Using microscopic analysis, the behavior of the breaking surfaces and the most common defects on fiber-reinforced composite sandwich structures were analyzed. The results of the mechanical tests indicated a significant influence of the filling density in the case of the three-point bending and impact tests. In contrast, the filling density does not decisively influence the structural performance of tensile tests of the fiber-reinforced composite sandwich structures. Composite sandwich structures, manufactured by fused filament fabrication process, were analyzed in terms of strength-to-mass ratio. Finite element analysis of the composite sandwich structures was performed to analyze the bending and tensile behavior.
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Additive Re-Manufacturing of Mechanically Recycled End-of-Life Glass Fiber-Reinforced Polymers for Value-Added Circular Design. MATERIALS 2020; 13:ma13163545. [PMID: 32796697 PMCID: PMC7476045 DOI: 10.3390/ma13163545] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 08/06/2020] [Accepted: 08/07/2020] [Indexed: 11/16/2022]
Abstract
Despite the large use of composites for industrial applications, their end-of-life management is still an open issue for manufacturing, especially in the wind energy sector. Additive manufacturing technology has been emerging as a solution, enhancing circular economy models, and using recycled composites for glass fiber-reinforced polymers is spreading as a new additive manufacturing trend. Nevertheless, their mechanical properties are still not comparable to pristine materials. The purpose of this paper is to examine the additive re-manufacturing of end-of-life glass fiber composites with mechanical performances that are comparable to virgin glass fiber-reinforced materials. Through a systematic characterization of the recyclate, requirements of the filler for the liquid deposition modeling process were identified. Printability and material surface quality of different formulations were analyzed using a low-cost modified 3D printer. Two hypothetical design concepts were also manufactured to validate the field of application. Furthermore, an understanding of the mechanical behavior was accomplished by means of tensile tests, and the results were compared with a benchmark formulation with virgin glass fibers. Mechanically recycled glass fibers show the capability to substitute pristine fillers, unlocking their use for new fields of application.
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Sustainable Additive Manufacturing: Mechanical Response of Acrylonitrile-Butadiene-Styrene over Multiple Recycling Processes. SUSTAINABILITY 2020. [DOI: 10.3390/su12093568] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Sustainability in additive manufacturing refers mainly to the recycling rate of polymers and composites used in fused filament fabrication (FFF), which nowadays are rapidly increasing in volume and value. Recycling of such materials is mostly a thermomechanical process that modifies their overall mechanical behavior. The present research work focuses on the acrylonitrile-butadiene-styrene (ABS) polymer, which is the second most popular material used in FFF-3D printing. In order to investigate the effect of the recycling courses on the mechanical response of the ABS polymer, an experimental simulation of the recycling process that isolates the thermomechanical treatment from other parameters (i.e., contamination, ageing, etc.) has been performed. To quantify the effect of repeated recycling processes on the mechanic response of the ABS polymer, a wide variety of mechanical tests were conducted on FFF-printed specimens. Regarding this, standard tensile, compression, flexion, impact and micro-hardness tests were performed per recycle repetition. The findings prove that the mechanical response of the recycled ABS polymer is generally improved over the recycling repetitions for a certain number of repetitions. An optimum overall mechanical behavior is found between the third and the fifth repetition, indicating a significant positive impact of the ABS polymer recycling, besides the environmental one.
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Effect of Diisocyanates as Compatibilizer on the Properties of BF/PBAT Composites by In Situ Reactive Compatibilization, Crosslinking and Chain Extension. MATERIALS 2020; 13:ma13030806. [PMID: 32050633 PMCID: PMC7040694 DOI: 10.3390/ma13030806] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/27/2019] [Revised: 02/06/2020] [Accepted: 02/06/2020] [Indexed: 11/16/2022]
Abstract
Due to the hydrophobic nature of poly (butylene terephthalate) (PBAT), and the hydrophilic nature of bamboo flour (BF), a BF/PBAT (50/50) blend shows low mechanical properties, and especially shows poor impact strength. In order to increase the interfacial adhesion between BF and PBAT, diisocyanate was used as a reactive compatibilizer to modify bamboo powder. A series of BF/PBAT composites were prepared by the method of mixing and melting in an internal mixer. After adding reactive compatibilizer 4,4′-methylenebis(phenyl isocyanate) (MDI), BF/PBAT (50/50) composites with high mechanical properties were successfully prepared. The tensile strength, elongation at break, and impact strength of the BF/MDI-2/PBAT composite with 2 wt % MDI content were increased by 1.9, 6.8, and 4.3 times respectively over the BF/PBAT blend without the added MDI. The higher toughening effect of MDI in BF/PBAT composites can be mainly ascribed to the improved interface bonding between BF and PBAT. The isocyanate group of MDI can react with the hydroxyl group on the BF surface and in situ formation of the carbamate group on the BF surface. The residual isocyanate can then react with the hydroxyl group of PBAT and form carbamate groups. The rheological behaviors demonstrate that addition of appropriate amounts of MDI, 1 wt % and 2 wt %, can promote the flowability of the molten BF/PBAT composites due to the decrease in interparticle interaction between bamboo powder and the increase in the thermal motion of the molecules.
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Building a Wind Power Plant from Scrap and Raising Public Awareness for Renewable Energy Technology in a Circular Economy. SUSTAINABILITY 2019. [DOI: 10.3390/su12010090] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Putting renewable energy to good use is necessary to deal with one of the greatest challenges of our time, namely, climate change. One problem, however, is that the technology we are using today turns into toxic waste at the end of its useful life, which in particular concerns the blades of wind turbines. We investigated how the ideas of a circular economy can be applied to address this issue. To this end, we built a small wind turbine almost entirely from used materials. The social purpose of this is to raise public awareness about renewable energy technology that is part of a circular economy. Therefore, we chose a reliable and easy-to-build concept for a small wind turbine, which can be reproduced in a “Do It Yourself” (DIY) approach. The core challenges we had to face consisted of how to acquire appropriate used materials and how to improve the efficiency of the system to obtain adequate electrical power. With a financial investment of less than €100, we built a Savonius wind turbine for use in, for example, a private garden to charge a power bank or other USB-chargeable devices.
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