A Comparative Environmental and Economic Analysis of CFRP Recycling Processes Using Life Cycle Assessment and Life Cycle Costing

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While CFRPs offer exceptional specific mechanical properties, their thermosetting matrix complicates recycling efforts, often resulting in energy-intensive disposal or significant waste accumulation. In recent years, considerable advancements have been made in CFRP recycling, with three primary processes emerging: mechanical, thermal, and chemical recycling. Existing comparisons of these methods have focused on the mechanical performance of recovered fibers, yet their broader sustainability implications warrant further exploration. This study undertakes a comprehensive Life Cycle Assessment (LCA) and Environmental Life Cycle Costing (eLCC) analysis of four key recycling techniques: mechanical recycling, pyrolysis, solvolysis, and high-voltage fragmentation. The analysis encompasses the metrics of cumulative energy demand, global warming potential, damage assessment by the Recipe endpoint method, and cost. In the analysis, available data from the literature, process models, and experimental and manufacturing procedures were used. The study's findings emphasize that CFRP recycling methods significantly reduce energy consumption and carbon footprints compared to the production of virgin fibers. Among the recycling techniques evaluated, mechanical recycling and high-voltage fragmentation demonstrate the lowest environmental impact, contributing positively to human health and the preservation of natural resources. The results enable the informed selection of sustainable and cost-effective CFRP recycling processes, supporting advancements in sustainable manufacturing and end-of-life product management. Carbon fiber reinforced plastics Recycling Life cycle assessment Life cycle costing Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 1. Introduction Carbon Fiber Reinforced Polymers (CFRPs), particularly thermoset composite materials, are widely used across aerospace, aviation, automotive, construction, and energy industries (Pantelakis and Tserpes 2020 ). CFRPs have become increasingly popular in engineering because of their excellent strength-to-weight ratio, stiffness, corrosion resistance, and overall mechanical, thermal, and chemical properties (Mouritz and Gibson 2007 ). The potential for weight reduction, which results in reduced fuel use and major environmental advantages, is a major factor in this shift toward CFRP (Borjan et al. 2021 ). Despite the performance benefits of thermoset composites, recyclability remains a significant barrier, particularly as these materials approach the end of their life cycle. Thermoset composites are not biodegradable and, unlike thermoplastics, cannot be melted and reshaped into new products (Pickering 2006 ). Although waste management has been a priority in the European Union in recent decades (Jacob 2006 ), many composite waste still ends up in landfills or incinerated (Ribeiro et al. 2015 ). For years, landfill and incineration have been the main disposal methods, but both have significant disadvantages: landfilling contributes to waste accumulation, while incineration consumes large amounts of energy (Karuppannan Gopalraj and Kärki 2020 ). To protect the environment, stricter legislation and economic initiatives are needed to encourage more sustainable recycling practices for composite materials (Pickering 2006 ). This has led to the development of three main recycling techniques for CFRPs: mechanical, thermal, and chemical recycling. The mechanical recycling process involves crushing, shredding, and milling CFRP components into smaller fragments and then grounding them into a fine powder. One of the primary advantages of mechanical recycling is that it generally requires less energy than other recycling technologies helping to lower also the cost (Aldosari et al. 2024 ). Thermal recycling, especially pyrolysis, has the ability to recover carbon fibers without the need for chemical solvents (Marsh 2008 ). While thermal recycling is effective for fiber recovery, additional oxidation steps may sometimes be required to improve fiber quality (Butenegro et al. 2021 ). Chemical recycling, or solvolysis, involves using a solvent to separate fibers from the matrix. This process uses various solvents applied at high pressure and temperature to break down the polymer matrix (Oliveux et al. 2015 ). A significant advantage of solvolysis is the recovery of valuable fibers and residual chemicals (Das and Varughese 2016 ). A recent innovative alternative for recycling CFRP that utilizes their electrical properties is high voltage fragmentation (Diani et al. 2023 ). Recycling thermoset polymer composites is motivated by the high cost of producing virgin fibers and the need to address environmental issues (Maheshwari and Deswal 2017 ). Recycling solutions aim to reduce both the financial and environmental costs of CFRP materials (Helbig et al. 2016 ). Furthermore, Life Cycle Assessment (LCA) has proven valuable for decision-making, providing insight into environmental and cost impacts. The evaluation of environmental and cost impacts of CFRP recycling processes have been studied by many authors: mechanical recycling (Howarth et al. 2014 ; Li et al. 2016 ), pyrolysis (Dong et al. 2018 ; Kawajiri and Kobayashi 2022 ; Yousef et al. 2024 ), solvolysis (La Rosa et al. 2021 ; Kawajiri and Kobayashi 2022 ), and high voltage fragmentation (Shuaib and Mativenga 2017 ; Leißner et al. 2018 ). Additionally, other studies have compared and evaluated various recycling methods based on their environmental and/or economic performance, highlighting differences and benefits among them. For instance, (Vo Dong et al. 2018 ) assessed the environmental and economic feasibility of several CFRP waste management methods, including grinding, pyrolysis, microwave, and supercritical water recycling. Using LCA and Life Cycle Costing (LCC), the study compared the effectiveness of these processes in recovering carbon fibers and reducing GWP. Furthermore,(Meng et al. 2018 ) examined recycling processes like pyrolysis, fluidized bed, and chemical recycling, demonstrating significant reductions in GWP and primary energy demand (PED) compared to landfill and incineration, with GWP reductions between 19 and 27 kg CO 2 eq and PED savings from 395 to 520 MJ per kg CFRP. (Khalil 2018 ) compared the environmental impacts of pyrolysis and solvolysis using supercritical water. The findings showed that solvolysis offers no significant gains over pyrolysis in terms of environmental and human health impacts. Finally, (Pillain et al. 2019 ) carried out a comparison of end-of-life scenarios, such as landfilling and incineration, with recycling technologies like pyrolysis, supercritical solvolysis, and electrodynamic fragmentation, shows that while recycling generally has a higher energy demand becomes environmentally advantageous when substitution of virgin products is considered. In this study, the environmental and economic impacts of CFRP recycling will be addressed utilizing the LCA and LCC approach using SimaPro software to evaluate four recycling processes: mechanical recycling, pyrolysis, solvolysis (with supercritical and subcritical water as a solvent), and high-voltage fragmentation. The aim of this study is: (i) to quantify and compare the environmental impacts of selected recycling methods using cumulative energy consumption and global warming potential over a 100-year horizon, and (ii) to assess the life cycle costs associated with each recycling process to provide a view of their economic feasibility. 2. LCA and LCC methodology According to ISO 14040 and 14044, LCA is the process of gathering and evaluating a product system's inputs, outputs, and environmental impacts during its entire life cycle. LCA consists of four phases ([CSL STYLE ERROR: reference with no printed form.]): Goal and Scope Definition: This stage establishes the study's objectives. Key methodological decisions are also determined here, such as defining the functional unit, setting system boundaries, identifying impact categories, and selecting Life Cycle Impact Assessment (LCIA) models. Life Cycle Inventory (LCI): This phase collects data and calculates system inputs and outputs. Data gathering includes foreground operations (such as manufacturing and packing) and background processes (such as the production of bought power and materials). Life Cycle Impact Assessment: This phase connects LCI data with environmental impact categories and indicators. LCIA methods categorize emissions into impact categories and quantify them in equivalent units, allowing for a more accurate evaluation of ecological impacts. Life Cycle Interpretation: The final phase aligns the outcomes of LCI and LCIA with the purpose and scope. This stage comprises checking for completeness, sensitivity, and consistency. LCC is an assessment tool of all costs associated with a product across its whole life cycle. Environmental Life Cycle Costing (eLCC) is designed to enhance an environmental Life Cycle Assessment (eLCA) by addressing the economic aspects of a product or a process. LCC is aligned with LCA, following the same structured steps throughout the analysis. This study will use eLCA and eLCC to assess each CFRP recycling method's environmental and economic effects. 2.1 Goal and Scope Definition The goal of this work is to assess and compare the environmental impacts and life cycle costs of four different recycling processes (mechanical recycling, pyrolysis, solvolysis (supercritical and subcritical water), and high-voltage fragmentation) for CFRP, with a baseline comparison to the production of CFRP from virgin carbon fibers. The functional unit is defined as 1 kg of CFRP waste. The CFRP plate used in this study was manufactured in the faculties of the Hellenic Aerospace Industry and consisted of 8 plies. They were made with CYTEC PRISM EP2400 epoxy resin and TENAX-E IMS65 E23 24K carbon fabric. The fiber volume fraction was 70.5% and each ply was 0.22 mm thick. The total amount of the CFRP manufactured was 1 kg. A cradle-to-grave life cycle model is chosen to assess the impacts. This approach includes all phases, from raw material extraction (cradle) to the final disposal or end-of-life treatment (grave). The processes are assumed to take place in Europe, according to the geographical relevance of the data sources. The analysis relies on data collected during experiments and the manufacturing stage, supplemented by information from the ecoinvent database and relevant literature. The LCA and LCC are carried out using SimaPro software. Categories of impacts such as global warming potential and cumulative energy demand are considered. Transport is excluded from the analysis as an assumption and, therefore, transport-related impacts are not considered in the LCA and LCC. 2.2 Life Cycle Inventory 2.2.1 Production of CFRP The initial step is the production of vCFs. This procedure begins with synthesizing acrylonitrile (AN) through the ammoxidation of propylene, known as the Sohio process. This process is well-documented in the ecoinvent database. Polyacrylonitrile (PAN) is synthesized through the polymerization of AN, including up to 5% by weight of co-monomers such as methyl acrylate or itaconic acid (Frank et al. 2012 ). The polymer is then dissolved in a solvent, typically dimethylformamide (DMF) (Kaur et al. 2016 ). For every kilogram of CF produced, approximately 0.61 kg of DMF is required, with a reuse efficiency of 99%. The production of PAN fibers requires energy inputs, primarily in the form of electricity and steam. These requirements for the production of PAN fibers are detailed by (Duflou et al. 2009 ; Meng et al. 2017 ). The spinning stage includes stretching and washing the fibers, followed by a sizing step. During sizing, approximately 10% by weight of protective silicone, primarily polydimethylsiloxane (PDMS), is applied to complete the PAN fiber production (Duflou et al. 2009 ). The inventory data for producing 1 kg of PAN are summarized in Table 1 . Table 1 Life cycle inventory for the production of 1 kg PAN Input Quantity Acrylonitrile 0.95 kg Methyl acrylate 0.05 kg Dimethylformamide solvent 0.0061 kg Polydimethylsiloxane 0.1 kg Electric energy 66.87 MJ Steam 18 kg The transformation from PAN to carbon fiber involves additional stages: oxidation (stabilization), carbonization, surface treatment, and sizing, ensuring the final material's mechanical properties and surface compatibility for applications (Fig. 1 ). The precursor fibers are stabilized by heating in an oxidizing atmosphere, which induces chemical changes to make them thermally stable. The stabilized fibers are then heated in an inert nitrogen atmosphere, where non-carbon atoms are removed, increasing carbon content to 93–95%. The carbonized fibers undergo treatment, to roughen the surface and introduce functional groups, enhancing adhesion to matrix resins (Park 2018 ). The final step is the sizing. So a protective coating is applied to the fibers to facilitate handling and improve compatibility with the matrix resin (Gill et al. 2016 ). An epoxy sizing of 1.3% by weight was considered, as specified in the carbon fiber datasheet. A weight ratio of 1.724 between the required PAN input and the obtained CF was assumed based on (Meng 2017 ). From these processes occurs the life cycle inventory for the production of virgin carbon fibers as illustrated in Fig. 2 . These data are derived from (Pillain et al. 2019 ). Background processes are modeled using the ecoinvent database, while the production of PAN is based on the description provided earlier. The typical electricity consumption for unidirectional (UD) production is calculated to be approximately 0.48 MJ/kg, based on data provided by (Stiller 1999 ). The UD carbon fabric used in this study incorporates a binder, which is used to stabilize the fabric layers during handling and impregnation in liquid composite molding (LCM) processes. Binders, typically based on epoxy, polyester, or other compatible resins, play a critical role in enhancing the compression, stability, and permeability of preforms (Terekhov and Chistyakov 2021 ). The binder is assumed to be low-density polyethylene (LDPE), with data derived from the ecoinvent database. The PRISM EP2400 epoxy resin is a single-component, toughened liquid epoxy system. It offers both flexibility in processing and the damage tolerance required for high-performance composite structures, such as aerospace applications. However, for this study, the life cycle modeling will assume that the epoxy resin is represented by the production process documented in the ecoinvent database. This involves the reaction of bisphenol-A and epichlorohydrin in the presence of a sodium hydroxide catalyst, reflecting a common industrial practice for commercial epoxy resin manufacturing. Furthermore, the epoxy resin used in this study includes a small amount of polyethersulfone (PES) copolymer to improve the performance characteristics. However, due to the minimal PES content and for simplification in LCA, the environmental impacts are approximated based on the data for the epoxy resin only, without explicitly considering the PES. The CFRP was fabricated using the Liquid Resin Infusion (LRI) process. In this process, dry carbon fabric is placed in a vacuum environment, and liquid resin is infused under controlled pressure. This method allows the exact resin distribution, minimizing voids and optimizing the material's mechanical properties (Karachalios et al. 2021 ). The energy consumption for LRI (or vacuum-assisted resin injection (VARI), a similar technique), is approximately 10.2 MJ/kg of composite produced (Suzuki and Takahashi 2005 ). Also, several consumables are required to support the LRI process. These include vacuum bags, peel ply, infusion mesh (resin flow media), tacky tape (sealant tape), as well as components like aspiration tubes, valves, vacuum hoses, and spiral tubing. These consumables, supplied by Easy Composites, are essential for creating the vacuum environment necessary for the LRI. For LCA, representative materials for these consumables were identified from the ecoinvent database, as shown in Table 2 . The quantities of these materials were carefully recorded during the manufacturing of the CFRP plate. It is important to note that consumables used in the manufacturing stage are considered waste after use. It is also assumed that there are no material losses or wastes, such as scraps or excess resin, generated during the manufacturing process. Table 2 Representation of consumables with materials and processes (selected from the ecoinvent database) Product Material Vacuum bag Nylon 6–6 Peel ply Polyethylene terephthalate, granulate Infusion mesh Polypropylene, granulate Tacky tape Synthetic rubber Aspiration tubes Nylon 6–6 Vacuum hose Polypropylene, granulate Valves, spiral tubing, etc Polypropylene, granulate 2.2.2 End-of-life processes- Recycling processes Mechanical recycling. Mechanical recycling of composites focuses on reducing the size of waste components for reuse in new materials (Pimenta and Pinho 2011 ). The recycling process typically starts with a primary crushing phase, where CFRPs are reduced in size to pieces about 50–100 mm. The next step involves secondary grinding, carried out using hammer mills or high-speed mills, which reduces the material into finer particles, generally ranging from 10 mm to under 50 µm (Pickering 2006 ; Palmer et al. 2009 ). The output of the recycling process consists of 24 wt% fine fibers, 19 wt% fine powders, and 57 wt% coarse recyclate (Palmer et al. 2010 ). The fine fibers can be repurposed as reinforcement in new composite materials by partially replacing raw fiber. However, there is a limit to the amount of rCF that can be used before the mechanical properties of the composite begin to degrade significantly (Pickering 2006 ). Material losses are common during the mechanical recycling of CFRP waste. Typically, about 10% of the original CFRP waste input is lost, mainly due to the steps of size reduction and grinding. The total energy demand for CFRP recycling in this process involves two stages: shredding and mechanical milling. The shredding stage requires 0.27 MJ/kg, while the next stage of mechanical milling has an energy demand of 2.03 MJ/kg based on (Howarth et al. 2014 ). This calculation for grinding is based on industrial grinding with a feed hopper with a processing rate of 10 kg/hour. Figure 3 provides a detailed flowchart of the mechanical recycling process. Pyrolysis. Pyrolysis is a widely studied thermal recycling process for composites, where materials are heated in the absence or presence of oxygen, and more recently, in steam (Oliveux et al. 2015 ). This method breaks down the resin matrix into oils, gases, and solid residues, including fibers that may require cleaning to remove char (Cunliffe and Williams 2003 ). Post-treatment at high temperatures (450–1300°C) can effectively clean the fibers but risks degrading their mechanical properties. Carbon fibers retain better properties depending on the pyrolysis conditions, balancing resin removal and fiber integrity (Meyer et al. 2009 ). The CFRP waste is first shredded using a mechanical mill using energy requirements data based on (Howarth et al. 2014 ). Pyrolysis, a thermal decomposition process, occurs in the absence of oxygen or with controlled oxygen flow at temperatures between 300°C and 800°C. Nitrogen is also used to prevent the oxidation of carbon fibers. Gases from resin degradation are collected, while solid residues (char) are usually disposed of in landfills. Energy consumption for recovering 1 kg of carbon fiber is estimated at approximately 30 MJ, producing rCF, ash, and emissions to the air (Witik et al. 2012 ). The LCI data are from (Meng et al. 2018 ) with nitrogen input referenced from(Lefeuvre et al. 2017 ). Figure 4 provides the flowchart. Solvolysis. Chemical recycling involves the depolymerization of polymer matrices using specific chemical solvents. This process recovers clean fibers, and matrix material, which can be transformed into monomers or petrochemical feedstocks. Known as solvolysis, the method varies by solvent type, including hydrolysis (water), glycolysis (glycols), etc. High temperatures and pressures are often applied under subcritical or supercritical conditions for faster, more efficient dissolution (Dang et al. 2005 ). The experimental setup involved a high-pressure, high-temperature reactor, where CFRP samples were treated with supercritical and subcritical water. The solvent was chosen for its environmental benefits, availability, and low toxicity (Vogiantzi and Tserpes 2023 ). In this process, CFRP waste is placed in the reactor without pre-shredding, as the reactor size is designed to accommodate the desired fiber length. Water is pressurized to about 250 bars for supercritical water and 170 bars for subcritical water. The temperatures are 380°C and 350°C respectively. Water consumption is approximately 10 L/kg of CFRP (Pillain et al. 2019 ). Energy requirements are calculated based on the water's heat capacity. To determine the energy required to heat the water, considering that heat capacity is not constant ([CSL STYLE ERROR: reference with no printed form.]), the equation is expressed as: $$\:Q=m{\int\:}_{{T}_{1}}^{{T}_{2}}{c}_{p}dT.$$ 1 Here, \(\:Q\) is the energy required (J), \(\:m\) is the mass of water (kg), \(\:{T}_{1}\) is the ambient temperature in °C, \(\:{T}_{2}\) is the desired temperature of the experiment in °C and \(\:{c}_{p}\) is the heat capacity (J/kg°C), which varies with temperature. This integral accounts for the changing value of \(\:{c}_{p}\) between 20°C and 380°C for the supercritical solvolysis and between 20°C and 380°C for the subcritical solvolysis. After calculating the energy requirements (approximately) for both supercritical and subcritical solvolysis, the results are presented in Fig. 5 (a) and Fig. 5 (b), respectively. These figures illustrate the input and output flows of each process. In this study, it is assumed that all water used during the solvolysis process is treated as waste, with no evaporation considered. Additionally, the entire quantity of the epoxy matrix is considered resin waste, as its recovery or reuse is not included within the scope of this analysis. High Voltage Fragmentation. High-voltage fragmentation (HVF) is a recycling process that uses electrical discharges to break down materials. High-voltage pulses are generated by a Marx generator, creating plasma channels in a water-filled vessel between electrodes (Roux et al. 2017 ). These plasma channels produce intense energy, high pressures, and shock waves, leading to cracks and fragmentation in the material, especially in weaker components (Bluhm et al. 1997 ). Water is the dielectric medium due to its low cost, availability, and environmental advantages (Roux et al. 2017 ). The process decomposes the materials through repeated pulses, eventually fragmenting the CFRP. The process for high-voltage shredding recycling starts by shredding the CFRP waste into smaller pieces. These shreds are processed in a high-voltage fragmentation system, where deionized water acts as a dielectric medium. During the process, nitrogen is used to create the optimal conditions for effective fragmentation. Afterward, the treated material undergoes filtration to separate and recover the fragmented CFs for further utilization. The filters used can be reused, therefore, they are excluded from consideration in the LCA and LCC. The data for this HVF process are based on findings from the study conducted by (Pillain et al. 2019 ), which details the energy consumption, operational parameters, and mass balance. The HVF recycling process is illustrated in Fig. 4 . In some recycling processes, such as solvolysis, the fibers require cleaning and oven drying to eliminate humidity. However, the consumption of water or solvents such as acetone for cleaning and the energy consumption of the drying oven are not included in the calculation. 2.3 Life cycle impact assessment In this study, the environmental impacts and costs of recycling CFRP waste and the production of CFRP are assessed using the SimaPro 9.6.01 software with the ecoinvent 3 database. The methods selected for LCA are Cumulative Energy Demand (CED), IPCC 2021 GWP100, and ReCiPe Endpoint. These methodologies enable the comprehensive assessment of energy use, climate change potential (in kg CO₂-eq over a 100-year horizon), and endpoint-level damage to ecosystems, human health, and resource depletion. For the LCC analysis, the method proposed by SimaPro was developed. This approach includes economic data within the LCA framework to evaluate the costs associated with the different recycling processes and CFRP production. The methodology includes cost categories such as operational costs, which cover energy and material costs, and integrates them into the life cycle stages to provide an economic assessment. 3. Results The final phase of LCA is the interpretation of the results. This phase evaluates the findings from the LCI and LCIA stages, providing an analysis of the environmental impacts of the studied scenarios. This is followed by the LCC, where the economic aspects of the same scenarios are assessed. Below, the interpretation of the results is presented. 3.1. Interpretation of LCA results After completing the LCA, the CED for producing 1kg of vCFs was calculated to be 747 MJ, while the GWP was determined to be 34.3 kg CO₂-eq. Additionally, a tree diagram illustrating the process of vCFs production is provided in Fig. 7 . The red lines in the tree diagram represent flow indicators, with line thickness corresponding to the environmental impact of each process stage. PAN production has a significant environmental footprint due to high electricity requirements and extensive use of chemicals such as AN. Afterward, we evaluate the manufacturing of the CFRP plate with consumables using the LRI technique. The CED method is applied to analyze the electricity consumption for CFRP production, and the GWP is calculated to assess the carbon footprint of the process. The CED analysis (Fig. 8 ) indicates that the production of vCFs has the highest impact on energy consumption. For this calculation, average electricity consumption data for Europe were used. However, it is important to note that this amount is likely to vary in different geographical areas due to differences in energy sources and efficiency. The total GWP is 25.2 kg CO₂eq, comprising: 23.3 kg CO₂eq from UD fabric production, reflecting the high impact of the carbon fiber production stage, 1.31 kg CO₂eq from epoxy resin production, and 0.624 kg CO₂eq from consumables such as vacuum bags. Also, an evaluation of the damage assessment using the Recipe Endpoint method is depicted in Fig. 9 . The results highlight the relative contributions of CFRP and consumables to environmental impacts, measured in points (Pt). It is important to note that the waste of consumables category does not contribute to the environmental impact in this analysis, as the waste is simply considered as discarded material with no further treatment applied such as landfill. The impacts are categorized into three areas: human health, ecosystems, and resources. The main impact is due to the manufacturing of CFRP itself, which significantly outweighs the contribution of consumables and waste. Specifically, the human health category is most affected by CFRP, due to the energy-intensive processes involved. To enable the comparison of the recycling methods, Table 3 presents the CED and GWP values for each process. Only the impacts of energy requirements and materials used during recycling processes are considered. Energy consumption associated with waste treatment, such as wastewater or epoxy resin waste management and potential energy recovery are excluded. Including these factors could reveal potential energy gain or revenue from energy recovery. Therefore, the focus remains on the energy inputs and material use during recycling processes. Table 3 CED and GWP of recycling for recycling processes Recycling process CED (MJ/kg CFRP waste) GWP (kg CO₂eq/kg CFRP waste) Mechanical recycling 5.82 0.218 Pyrolysis 66.3 2.84 Solvolysis-subcritical water 49.8 1.87 Solvolysis-supercritical water 66.3 2.49 HVF 4.97 0.0796 Recycling processes have significantly lower energy consumption and carbon footprints compared to vCFs production. Among the recycling methods, mechanical recycling and HVF exhibit the lowest CED and GWP values, primarily due to their minimal energy requirements. In contrast, pyrolysis and supercritical water solvolysis require substantial energy inputs, with pyrolysis relying on natural gas, and solvolysis needing high energy to surpass the critical point of water and reach the required 380°C temperature for processing. Additionally, an evaluation of the damage assessment for the different recycling methods is presented (Fig. 10 ). Μechanical recycling and HVF show minimal impacts in all categories, benefiting human health and resources in particular. In contrast, pyrolysis and solvolysis with supercritical water have significant negative effects on human health and ecosystems. Pyrolysis, in particular, has significant environmental impacts, especially in terms of resources. Solvolysis with subcritical water, however, has more balanced environmental impacts. 3.2. LCC results In the LCC, only material and energy costs are considered. The country of material production is considered; however, transportation costs are excluded from the analysis. Material costs are obtained from suppliers selling these materials, while energy costs are based on the average energy price in Europe ([CSL STYLE ERROR: reference with no printed form.]). The LCC data inventory for materials and energy costs associated with manufacturing CFRP plate is detailed in Table 4 , with costs presented in €/kg for each input. It accounts for the total cost of producing carbon fiber, epoxy resin, and consumables. These costs are relatively high, as the calculation is based on the production of a single kilogram rather than mass production, where economies of scale would reduce costs. Additionally, the analysis considers raw material and energy costs, not the market price of finished products like carbon fiber. After calculations, the total cost for producing 1 kg of CFRP is 211€. Table 4 LCI of costs for materials and energy for the production of CFRP Input Impact category Factor Unit UD production Material costs 246 €/kg Epoxy resin Material costs 100 €/kg Consumables Material costs 16.5 €/kg Electricity Energy costs 0.052 €/MJ For the recycling processes, only the material and energy costs associated with the operational aspects of the methods were considered. These include the inputs and energy consumed during the recycling stages. However, potential revenue from recycled carbon fibers (rCFs) could also be factored in (not included in this analysis). If the quality and mechanical properties of the recycled fibers are sufficient, they can be reused. This could offset part of the recycling costs. As a result, reusing recycled fibers can contribute positively to the overall economic viability of the processes. In Fig. 11 , the material and energy costs for each recycling process are displayed, offering a detailed overview of the costs associated with each method. In mechanical recycling and pyrolysis, the materials costs are either negligible or zero. However, for solvolysis and HVF, the primary material cost comes from deionized water. Regarding energy costs, pyrolysis stands out with the highest cost due to its significant energy demands. Solvolysis with supercritical water follows as it requires considerable energy to heat the water to 380°C. The total cost for each recycling process is as follows: mechanical recycling costs 0.106 €/kg CFRP waste, pyrolysis costs 4.66 €/kg, solvolysis with subcritical water costs 50.9 €/kg, solvolysis with supercritical water costs 51.2 €/kg, and HVF costs 155 €/kg. 4. Discussion This paper discusses four recycling methods for CFRP, including the three main recycling methods and one innovative approach (HVF). When assessing these methods, it is important to consider both environmental impacts and cost factors such as capital and operational costs. However, the quality of the recycled fibers also plays a critical role - if the quality of the fibers is poor, recycling may not be viable. In addition, the technology readiness levels of these methods (TRL) vary. Mechanical recycling and pyrolysis are at a high TRL, which makes them ready for use on an industrial scale, while the other methods are still in the laboratory scale phase (Rybicka et al. 2016 ). This difference highlights the challenge of scaling up recycling processes from small samples or parts to complete structures. A significant limitation of this study is the assumption that the fibers are perfectly recycled, 100% clean, and resin-free. In reality, this is not always the case, and additional steps are often required to ensure the fibers are thoroughly cleaned. These additional steps inevitably contribute to environmental impacts and economic costs, yet they are challenging to quantify and integrate into the study. Furthermore, chemical recycling, particularly solvolysis, remains an evolving field. This method allows for a diverse selection of solutions and process parameters, including temperature, pressure, and reaction time (Utekar et al. 2021 ). To evaluate solvolysis effectively, it is essential to optimize process parameters to achieve a balance among mechanical properties, environmental impact, and cost efficiency. Furthermore, only the costs of materials and energy used in the recycling processes have been considered in this study. Potential costs or revenues associated with waste, recycled fibers, and possible energy recovery from these processes have not been included. The integration of these factors could provide a more complete estimate of total costs. For instance, (Shehab et al. 2021 ) categorize costs into dismantling, transportation, operation, and capital and present a fuzzy logic-based system for estimating the recycling costs of CFRPs. Depending on the perspective of the study, recycling methods could be evaluated as a service, with the cost of providing this service being included in the analysis. Last but not least, the most important limitation of this study is that the LCI data used for the assessment comes from various sources, including literature, experiments, and industry reports. As a result, the materials analyzed in each recycling method differ, which could impact the results. Specifically, although the study focuses on epoxy resin, the data used is derived from different types of epoxy resins. Thus, variations in the chemical formulation of the resins might affect their environmental impacts. Therefore, a more reliable comparison of recycling processes would require the use of the same material (CFRP) and quantity across all methods. Additionally, input and energy requirements should be consistently calculated for each process to ensure an accurate assessment of their environmental impacts and operational costs. 4. Conclusions This paper evaluates the production of vCFs and the manufacturing of CFRPs using the LRI method. Additionally, it compares three conventional CFRP recycling methods—mechanical recycling, pyrolysis, and solvolysis—alongside an innovative approach, HVF. A comprehensive cost analysis of material and energy requirements accompanies these comparisons. The LCA indicates that mechanical recycling is the most environmentally friendly and cost-effective method, with the lowest energy consumption and carbon footprint. Conversely, pyrolysis and solvolysis are associated with significantly higher energy demands and environmental impacts. Nevertheless, the preservation of carbon fiber mechanical properties should be incorporated into future assessments, ensuring the alignment of environmental and economic analyses with fiber reuse potential. The study is limited by assumptions such as complete resin decomposition, which may impact accuracy. Future research should aim to standardize CFRP across recycling methods, investigate energy recovery opportunities, and examine factors influencing the quality and reuse potential of recycled fibers. Declarations CRediT authorship contribution statement Konstantinos Tserpes: Methodology, Writing - review & editing, Conceptualization, Supervision. Christina Vogiantzi: Methodology, Writing - original draft, Software, Investigation, Visualization. Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. 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Polymers 13:4370. https://doi.org/10.3390/polym13244370 Shuaib NA, Mativenga PT (2017) Carbon Footprint Analysis of Fibre Reinforced Composite Recycling Processes. Procedia Manuf 7:183–190. https://doi.org/10.1016/j.promfg.2016.12.046 Stiller H (1999) Material intensity of advanced composite materials. Results of asudy for the Verbundwerkstofflabor Bremen e.V Suzuki T, Takahashi J (2005) Prediction of energy intensity of carbon fiber reinforced plastics for mass-produced passenger cars Terekhov IV, Chistyakov EM (2021) Binders Used for the Manufacturing of Composite Materials by Liquid Composite Molding. Polymers 14:87. https://doi.org/10.3390/polym14010087 Utekar S, V K S, More N, Rao A (2021) Comprehensive study of recycling of thermosetting polymer composites – Driving force, challenges and methods. Compos Part B: Eng 207:108596. https://doi.org/10.1016/j.compositesb.2020.108596 Vo Dong PA, Azzaro-Pantel C, Cadene A-L (2018) Economic and environmental assessment of recovery and disposal pathways for CFRP waste management. Resour Conserv Recycl 133:63–75. https://doi.org/10.1016/j.resconrec.2018.01.024 Vogiantzi C, Tserpes K (2023) On the Definition, Assessment, and Enhancement of Circular Economy across Various Industrial Sectors: A Literature Review and Recent Findings. Sustainability 15:16532. https://doi.org/10.3390/su152316532 Witik RA, Gaille F, Teuscher R et al (2012) Economic and environmental assessment of alternative production methods for composite aircraft components. J Clean Prod 29–30:91–102. https://doi.org/10.1016/j.jclepro.2012.02.028 Yousef S, Eimontas J, Stasiulaitiene I et al (2024) Recovery of energy and carbon fibre from wind turbine blades waste (carbon fibre/unsaturated polyester resin) using pyrolysis process and its life-cycle assessment. Environ Res 245:118016. https://doi.org/10.1016/j.envres.2023.118016 European Platform on LCA | EPLCA https://eplca.jrc.ec.europa.eu/lifecycleassessment.html . Accessed 23 Jul 2024a Water - Specific Heat vs Temperature. https://www.engineeringtoolbox.com/specific-heat-capacity-water-d_660.html . Accessed 25 Nov 2024b Electricity price statistics https://ec.europa.eu/eurostat/statistics-explained/index.php?title=Electricity_price_statistics . Accessed 27 Nov 2024c Additional Declarations The authors declare no competing interests. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. 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fibers\u003c/p\u003e","description":"","filename":"image1.png","url":"https://assets-eu.researchsquare.com/files/rs-5626810/v1/b8b5a1b79c8c6d4ec987860c.png"},{"id":71308196,"identity":"27f9cc1a-439b-489a-98a6-91a4bd3c5558","added_by":"auto","created_at":"2024-12-13 06:53:03","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":280267,"visible":true,"origin":"","legend":"\u003cp\u003eLife cycle inventory for the production of virgin fibers\u003c/p\u003e","description":"","filename":"image2.png","url":"https://assets-eu.researchsquare.com/files/rs-5626810/v1/243f63c49c6897873965ab20.png"},{"id":71308197,"identity":"68c4a242-fb85-4da1-b0ad-c26436bb3c98","added_by":"auto","created_at":"2024-12-13 06:53:03","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":175242,"visible":true,"origin":"","legend":"\u003cp\u003eFlowchart of the mechanical recycling process\u003c/p\u003e","description":"","filename":"image3.png","url":"https://assets-eu.researchsquare.com/files/rs-5626810/v1/597afab827fe57f6fed587a7.png"},{"id":71309768,"identity":"c4a7fbb4-5af1-4aba-89da-f6b1102bc8ad","added_by":"auto","created_at":"2024-12-13 07:09:03","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":184926,"visible":true,"origin":"","legend":"\u003cp\u003eFlowchart of the pyrolysis process\u003c/p\u003e","description":"","filename":"image4.png","url":"https://assets-eu.researchsquare.com/files/rs-5626810/v1/2af60bb1dd5dbaf4ffa5ebc1.png"},{"id":71308206,"identity":"f4f6a72b-8cf4-48c2-b183-8b0f775691cc","added_by":"auto","created_at":"2024-12-13 06:53:04","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":172458,"visible":true,"origin":"","legend":"\u003cp\u003eFlowchart of the solvolysis process (a) with supercritical water, (b) with subcritical water\u003c/p\u003e","description":"","filename":"image5.png","url":"https://assets-eu.researchsquare.com/files/rs-5626810/v1/dbf1ad0478142427ec9e0e0c.png"},{"id":71308221,"identity":"87141e7a-fc6a-404e-9dd9-5cf6c2a9913e","added_by":"auto","created_at":"2024-12-13 06:53:05","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":197399,"visible":true,"origin":"","legend":"\u003cp\u003eFlowchart of the HVF recycling process\u003c/p\u003e","description":"","filename":"image6.png","url":"https://assets-eu.researchsquare.com/files/rs-5626810/v1/acf0adc2e9e83d054e4a9c93.png"},{"id":71309021,"identity":"bf4efbab-140a-498d-a70a-4eb93b811a59","added_by":"auto","created_at":"2024-12-13 07:01:04","extension":"jpeg","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":45683,"visible":true,"origin":"","legend":"\u003cp\u003eTree diagram of the production of virgin fibers.\u003c/p\u003e","description":"","filename":"image7.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-5626810/v1/87cad8fa73aef2b3c42f5a4f.jpeg"},{"id":71308229,"identity":"8a8b1848-da61-4bd7-973e-d6752493327a","added_by":"auto","created_at":"2024-12-13 06:53:06","extension":"jpeg","order_by":8,"title":"Figure 8","display":"","copyAsset":false,"role":"figure","size":105765,"visible":true,"origin":"","legend":"\u003cp\u003eCED for the manufacturing process of CFRP plate\u003c/p\u003e","description":"","filename":"image8.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-5626810/v1/f6c7b1626ca364aeb9aa9724.jpeg"},{"id":71309026,"identity":"63825264-f102-47a3-b000-f6c319091fb3","added_by":"auto","created_at":"2024-12-13 07:01:04","extension":"jpeg","order_by":9,"title":"Figure 9","display":"","copyAsset":false,"role":"figure","size":113986,"visible":true,"origin":"","legend":"\u003cp\u003eDamage assessment of CFRP production using Recipe Endpoint\u003c/p\u003e","description":"","filename":"image9.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-5626810/v1/0723431b37a894d7e1a8ab94.jpeg"},{"id":71308216,"identity":"bc494407-19b8-487c-8244-4c6d8d3519ae","added_by":"auto","created_at":"2024-12-13 06:53:04","extension":"jpeg","order_by":10,"title":"Figure 10","display":"","copyAsset":false,"role":"figure","size":136114,"visible":true,"origin":"","legend":"\u003cp\u003eComparison of the damage assessment of the recycling processes\u003c/p\u003e","description":"","filename":"image10.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-5626810/v1/800bd8ad5865cdbc11f4303e.jpeg"},{"id":71308210,"identity":"a9a929c3-38d9-4f45-bac6-0b0d66a53e36","added_by":"auto","created_at":"2024-12-13 06:53:04","extension":"jpeg","order_by":11,"title":"Figure 11","display":"","copyAsset":false,"role":"figure","size":128675,"visible":true,"origin":"","legend":"\u003cp\u003eComparison of materials and energy costs of the recycling processes\u003c/p\u003e","description":"","filename":"image11.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-5626810/v1/3e352a1aa72faebe3fa33e9e.jpeg"},{"id":71310086,"identity":"a303eb7a-53a2-4ce8-b918-6d6d94ea652a","added_by":"auto","created_at":"2024-12-13 07:17:05","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2233817,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-5626810/v1/2a3eac86-f67e-4d1c-acb1-66be490b4cf3.pdf"}],"financialInterests":"The authors declare no competing interests.","formattedTitle":"\u003cp\u003eA Comparative Environmental and Economic Analysis of CFRP Recycling Processes Using Life Cycle Assessment and Life Cycle Costing\u003c/p\u003e","fulltext":[{"header":"1. Introduction","content":"\u003cp\u003eCarbon Fiber Reinforced Polymers (CFRPs), particularly thermoset composite materials, are widely used across aerospace, aviation, automotive, construction, and energy industries (Pantelakis and Tserpes \u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e2020\u003c/span\u003e). CFRPs have become increasingly popular in engineering because of their excellent strength-to-weight ratio, stiffness, corrosion resistance, and overall mechanical, thermal, and chemical properties (Mouritz and Gibson \u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e2007\u003c/span\u003e). The potential for weight reduction, which results in reduced fuel use and major environmental advantages, is a major factor in this shift toward CFRP (Borjan et al. \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e2021\u003c/span\u003e). Despite the performance benefits of thermoset composites, recyclability remains a significant barrier, particularly as these materials approach the end of their life cycle. Thermoset composites are not biodegradable and, unlike thermoplastics, cannot be melted and reshaped into new products (Pickering \u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e2006\u003c/span\u003e). Although waste management has been a priority in the European Union in recent decades (Jacob \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e2006\u003c/span\u003e), many composite waste still ends up in landfills or incinerated (Ribeiro et al. \u003cspan citationid=\"CR40\" class=\"CitationRef\"\u003e2015\u003c/span\u003e). For years, landfill and incineration have been the main disposal methods, but both have significant disadvantages: landfilling contributes to waste accumulation, while incineration consumes large amounts of energy (Karuppannan Gopalraj and K\u0026auml;rki \u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e2020\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eTo protect the environment, stricter legislation and economic initiatives are needed to encourage more sustainable recycling practices for composite materials (Pickering \u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e2006\u003c/span\u003e). This has led to the development of three main recycling techniques for CFRPs: mechanical, thermal, and chemical recycling. The mechanical recycling process involves crushing, shredding, and milling CFRP components into smaller fragments and then grounding them into a fine powder. One of the primary advantages of mechanical recycling is that it generally requires less energy than other recycling technologies helping to lower also the cost (Aldosari et al. \u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e2024\u003c/span\u003e). Thermal recycling, especially pyrolysis, has the ability to recover carbon fibers without the need for chemical solvents (Marsh \u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e2008\u003c/span\u003e). While thermal recycling is effective for fiber recovery, additional oxidation steps may sometimes be required to improve fiber quality (Butenegro et al. \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e2021\u003c/span\u003e). Chemical recycling, or solvolysis, involves using a solvent to separate fibers from the matrix. This process uses various solvents applied at high pressure and temperature to break down the polymer matrix (Oliveux et al. \u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e2015\u003c/span\u003e). A significant advantage of solvolysis is the recovery of valuable fibers and residual chemicals (Das and Varughese \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e2016\u003c/span\u003e). A recent innovative alternative for recycling CFRP that utilizes their electrical properties is high voltage fragmentation (Diani et al. \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e2023\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eRecycling thermoset polymer composites is motivated by the high cost of producing virgin fibers and the need to address environmental issues (Maheshwari and Deswal \u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e2017\u003c/span\u003e). Recycling solutions aim to reduce both the financial and environmental costs of CFRP materials (Helbig et al. \u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e2016\u003c/span\u003e). Furthermore, Life Cycle Assessment (LCA) has proven valuable for decision-making, providing insight into environmental and cost impacts. The evaluation of environmental and cost impacts of CFRP recycling processes have been studied by many authors: mechanical recycling (Howarth et al. \u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e2014\u003c/span\u003e; Li et al. \u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e2016\u003c/span\u003e), pyrolysis (Dong et al. \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e2018\u003c/span\u003e; Kawajiri and Kobayashi \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e2022\u003c/span\u003e; Yousef et al. \u003cspan citationid=\"CR52\" class=\"CitationRef\"\u003e2024\u003c/span\u003e), solvolysis (La Rosa et al. \u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e2021\u003c/span\u003e; Kawajiri and Kobayashi \u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e2022\u003c/span\u003e), and high voltage fragmentation (Shuaib and Mativenga \u003cspan citationid=\"CR44\" class=\"CitationRef\"\u003e2017\u003c/span\u003e; Lei\u0026szlig;ner et al. \u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e2018\u003c/span\u003e). Additionally, other studies have compared and evaluated various recycling methods based on their environmental and/or economic performance, highlighting differences and benefits among them. For instance, (Vo Dong et al. \u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e2018\u003c/span\u003e) assessed the environmental and economic feasibility of several CFRP waste management methods, including grinding, pyrolysis, microwave, and supercritical water recycling. Using LCA and Life Cycle Costing (LCC), the study compared the effectiveness of these processes in recovering carbon fibers and reducing GWP. Furthermore,(Meng et al. \u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e2018\u003c/span\u003e) examined recycling processes like pyrolysis, fluidized bed, and chemical recycling, demonstrating significant reductions in GWP and primary energy demand (PED) compared to landfill and incineration, with GWP reductions between 19 and 27 kg CO\u003csub\u003e2\u003c/sub\u003eeq and PED savings from 395 to 520 MJ per kg CFRP. (Khalil \u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e2018\u003c/span\u003e) compared the environmental impacts of pyrolysis and solvolysis using supercritical water. The findings showed that solvolysis offers no significant gains over pyrolysis in terms of environmental and human health impacts. Finally, (Pillain et al. \u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e2019\u003c/span\u003e) carried out a comparison of end-of-life scenarios, such as landfilling and incineration, with recycling technologies like pyrolysis, supercritical solvolysis, and electrodynamic fragmentation, shows that while recycling generally has a higher energy demand becomes environmentally advantageous when substitution of virgin products is considered.\u003c/p\u003e \u003cp\u003eIn this study, the environmental and economic impacts of CFRP recycling will be addressed utilizing the LCA and LCC approach using SimaPro software to evaluate four recycling processes: mechanical recycling, pyrolysis, solvolysis (with supercritical and subcritical water as a solvent), and high-voltage fragmentation. The aim of this study is: (i) to quantify and compare the environmental impacts of selected recycling methods using cumulative energy consumption and global warming potential over a 100-year horizon, and (ii) to assess the life cycle costs associated with each recycling process to provide a view of their economic feasibility.\u003c/p\u003e"},{"header":"2. LCA and LCC methodology","content":"\u003cp\u003eAccording to ISO 14040 and 14044, LCA is the process of gathering and evaluating a product system's inputs, outputs, and environmental impacts during its entire life cycle. LCA consists of four phases ([CSL STYLE ERROR: reference with no printed form.]):\u003c/p\u003e\n\u003col\u003e\n\u003cli\u003e\n\u003cp\u003eGoal and Scope Definition: This stage establishes the study's objectives. Key methodological decisions are also determined here, such as defining the functional unit, setting system boundaries, identifying impact categories, and selecting Life Cycle Impact Assessment (LCIA) models.\u003c/p\u003e\n\u003c/li\u003e\n\u003cli\u003e\n\u003cp\u003eLife Cycle Inventory (LCI): This phase collects data and calculates system inputs and outputs. Data gathering includes foreground operations (such as manufacturing and packing) and background processes (such as the production of bought power and materials).\u003c/p\u003e\n\u003c/li\u003e\n\u003cli\u003e\n\u003cp\u003eLife Cycle Impact Assessment: This phase connects LCI data with environmental impact categories and indicators. LCIA methods categorize emissions into impact categories and quantify them in equivalent units, allowing for a more accurate evaluation of ecological impacts.\u003c/p\u003e\n\u003c/li\u003e\n\u003cli\u003e\n\u003cp\u003eLife Cycle Interpretation: The final phase aligns the outcomes of LCI and LCIA with the purpose and scope. This stage comprises checking for completeness, sensitivity, and consistency.\u003c/p\u003e\n\u003c/li\u003e\n\u003c/ol\u003e\n\u003cp\u003eLCC is an assessment tool of all costs associated with a product across its whole life cycle. Environmental Life Cycle Costing (eLCC) is designed to enhance an environmental Life Cycle Assessment (eLCA) by addressing the economic aspects of a product or a process. LCC is aligned with LCA, following the same structured steps throughout the analysis. This study will use eLCA and eLCC to assess each CFRP recycling method's environmental and economic effects.\u003c/p\u003e\n\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e\n\u003ch2\u003e2.1 Goal and Scope Definition\u003c/h2\u003e\n\u003cp\u003eThe goal of this work is to assess and compare the environmental impacts and life cycle costs of four different recycling processes (mechanical recycling, pyrolysis, solvolysis (supercritical and subcritical water), and high-voltage fragmentation) for CFRP, with a baseline comparison to the production of CFRP from virgin carbon fibers. The functional unit is defined as 1 kg of CFRP waste. The CFRP plate used in this study was manufactured in the faculties of the Hellenic Aerospace Industry and consisted of 8 plies. They were made with CYTEC PRISM EP2400 epoxy resin and TENAX-E IMS65 E23 24K carbon fabric. The fiber volume fraction was 70.5% and each ply was 0.22 mm thick. The total amount of the CFRP manufactured was 1 kg. A cradle-to-grave life cycle model is chosen to assess the impacts. This approach includes all phases, from raw material extraction (cradle) to the final disposal or end-of-life treatment (grave). The processes are assumed to take place in Europe, according to the geographical relevance of the data sources. The analysis relies on data collected during experiments and the manufacturing stage, supplemented by information from the ecoinvent database and relevant literature. The LCA and LCC are carried out using SimaPro software. Categories of impacts such as global warming potential and cumulative energy demand are considered. Transport is excluded from the analysis as an assumption and, therefore, transport-related impacts are not considered in the LCA and LCC.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec4\" class=\"Section2\"\u003e\n\u003ch2\u003e2.2 Life Cycle Inventory\u003c/h2\u003e\n\u003cdiv id=\"Sec5\" class=\"Section3\"\u003e\n\u003ch2\u003e2.2.1 Production of CFRP\u003c/h2\u003e\n\u003cp\u003eThe initial step is the production of vCFs. This procedure begins with synthesizing acrylonitrile (AN) through the ammoxidation of propylene, known as the Sohio process. This process is well-documented in the ecoinvent database. Polyacrylonitrile (PAN) is synthesized through the polymerization of AN, including up to 5% by weight of co-monomers such as methyl acrylate or itaconic acid (Frank et al. \u003cspan class=\"CitationRef\"\u003e2012\u003c/span\u003e). The polymer is then dissolved in a solvent, typically dimethylformamide (DMF) (Kaur et al. \u003cspan class=\"CitationRef\"\u003e2016\u003c/span\u003e). For every kilogram of CF produced, approximately 0.61 kg of DMF is required, with a reuse efficiency of 99%. The production of PAN fibers requires energy inputs, primarily in the form of electricity and steam. These requirements for the production of PAN fibers are detailed by (Duflou et al. \u003cspan class=\"CitationRef\"\u003e2009\u003c/span\u003e; Meng et al. \u003cspan class=\"CitationRef\"\u003e2017\u003c/span\u003e). The spinning stage includes stretching and washing the fibers, followed by a sizing step. During sizing, approximately 10% by weight of protective silicone, primarily polydimethylsiloxane (PDMS), is applied to complete the PAN fiber production (Duflou et al. \u003cspan class=\"CitationRef\"\u003e2009\u003c/span\u003e). The inventory data for producing 1 kg of PAN are summarized in Table\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e.\u003c/p\u003e\n\u003cdiv class=\"gridtable\"\u003e\n\u003cdiv class=\"colspec\" align=\"left\"\u003e\u0026nbsp;\u003c/div\u003e\n\u003cdiv class=\"colspec\" align=\"left\"\u003e\u0026nbsp;\u003c/div\u003e\n\u003ctable id=\"Tab1\" border=\"1\"\u003e\u003ccaption\u003e\n\u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e\n\u003cdiv class=\"CaptionContent\"\u003e\n\u003cp\u003eLife cycle inventory for the production of 1 kg PAN\u003c/p\u003e\n\u003c/div\u003e\n\u003c/caption\u003e\n\u003cthead\u003e\n\u003ctr\u003e\n\u003cth align=\"left\"\u003e\n\u003cp\u003eInput\u003c/p\u003e\n\u003c/th\u003e\n\u003cth align=\"left\"\u003e\n\u003cp\u003eQuantity\u003c/p\u003e\n\u003c/th\u003e\n\u003c/tr\u003e\n\u003c/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eAcrylonitrile\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e0.95 kg\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eMethyl acrylate\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e0.05 kg\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eDimethylformamide solvent\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e0.0061 kg\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003ePolydimethylsiloxane\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e0.1 kg\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eElectric energy\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e66.87 MJ\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eSteam\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e18 kg\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003c/tbody\u003e\n\u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003eThe transformation from PAN to carbon fiber involves additional stages: oxidation (stabilization), carbonization, surface treatment, and sizing, ensuring the final material's mechanical properties and surface compatibility for applications (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e). The precursor fibers are stabilized by heating in an oxidizing atmosphere, which induces chemical changes to make them thermally stable. The stabilized fibers are then heated in an inert nitrogen atmosphere, where non-carbon atoms are removed, increasing carbon content to 93\u0026ndash;95%. The carbonized fibers undergo treatment, to roughen the surface and introduce functional groups, enhancing adhesion to matrix resins (Park \u003cspan class=\"CitationRef\"\u003e2018\u003c/span\u003e). The final step is the sizing. So a protective coating is applied to the fibers to facilitate handling and improve compatibility with the matrix resin (Gill et al. \u003cspan class=\"CitationRef\"\u003e2016\u003c/span\u003e). An epoxy sizing of 1.3% by weight was considered, as specified in the carbon fiber datasheet.\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eA weight ratio of 1.724 between the required PAN input and the obtained CF was assumed based on (Meng \u003cspan class=\"CitationRef\"\u003e2017\u003c/span\u003e). From these processes occurs the life cycle inventory for the production of virgin carbon fibers as illustrated in Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e. These data are derived from (Pillain et al. \u003cspan class=\"CitationRef\"\u003e2019\u003c/span\u003e). Background processes are modeled using the ecoinvent database, while the production of PAN is based on the description provided earlier.\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThe typical electricity consumption for unidirectional (UD) production is calculated to be approximately 0.48 MJ/kg, based on data provided by (Stiller \u003cspan class=\"CitationRef\"\u003e1999\u003c/span\u003e). The UD carbon fabric used in this study incorporates a binder, which is used to stabilize the fabric layers during handling and impregnation in liquid composite molding (LCM) processes. Binders, typically based on epoxy, polyester, or other compatible resins, play a critical role in enhancing the compression, stability, and permeability of preforms (Terekhov and Chistyakov \u003cspan class=\"CitationRef\"\u003e2021\u003c/span\u003e). The binder is assumed to be low-density polyethylene (LDPE), with data derived from the ecoinvent database.\u003c/p\u003e\n\u003cp\u003eThe PRISM EP2400 epoxy resin is a single-component, toughened liquid epoxy system. It offers both flexibility in processing and the damage tolerance required for high-performance composite structures, such as aerospace applications. However, for this study, the life cycle modeling will assume that the epoxy resin is represented by the production process documented in the ecoinvent database. This involves the reaction of bisphenol-A and epichlorohydrin in the presence of a sodium hydroxide catalyst, reflecting a common industrial practice for commercial epoxy resin manufacturing. Furthermore, the epoxy resin used in this study includes a small amount of polyethersulfone (PES) copolymer to improve the performance characteristics. However, due to the minimal PES content and for simplification in LCA, the environmental impacts are approximated based on the data for the epoxy resin only, without explicitly considering the PES.\u003c/p\u003e\n\u003cp\u003eThe CFRP was fabricated using the Liquid Resin Infusion (LRI) process. In this process, dry carbon fabric is placed in a vacuum environment, and liquid resin is infused under controlled pressure. This method allows the exact resin distribution, minimizing voids and optimizing the material's mechanical properties (Karachalios et al. \u003cspan class=\"CitationRef\"\u003e2021\u003c/span\u003e). The energy consumption for LRI (or vacuum-assisted resin injection (VARI), a similar technique), is approximately 10.2 MJ/kg of composite produced (Suzuki and Takahashi \u003cspan class=\"CitationRef\"\u003e2005\u003c/span\u003e).\u003c/p\u003e\n\u003cp\u003eAlso, several consumables are required to support the LRI process. These include vacuum bags, peel ply, infusion mesh (resin flow media), tacky tape (sealant tape), as well as components like aspiration tubes, valves, vacuum hoses, and spiral tubing. These consumables, supplied by Easy Composites, are essential for creating the vacuum environment necessary for the LRI. For LCA, representative materials for these consumables were identified from the ecoinvent database, as shown in Table\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e. The quantities of these materials were carefully recorded during the manufacturing of the CFRP plate. It is important to note that consumables used in the manufacturing stage are considered waste after use. It is also assumed that there are no material losses or wastes, such as scraps or excess resin, generated during the manufacturing process.\u003c/p\u003e\n\u003cdiv class=\"gridtable\"\u003e\n\u003cdiv class=\"colspec\" align=\"left\"\u003e\u0026nbsp;\u003c/div\u003e\n\u003cdiv class=\"colspec\" align=\"left\"\u003e\u0026nbsp;\u003c/div\u003e\n\u003ctable id=\"Tab2\" border=\"1\"\u003e\u003ccaption\u003e\n\u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e\n\u003cdiv class=\"CaptionContent\"\u003e\n\u003cp\u003eRepresentation of consumables with materials and processes (selected from the ecoinvent database)\u003c/p\u003e\n\u003c/div\u003e\n\u003c/caption\u003e\n\u003cthead\u003e\n\u003ctr\u003e\n\u003cth align=\"left\"\u003e\n\u003cp\u003eProduct\u003c/p\u003e\n\u003c/th\u003e\n\u003cth align=\"left\"\u003e\n\u003cp\u003eMaterial\u003c/p\u003e\n\u003c/th\u003e\n\u003c/tr\u003e\n\u003c/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eVacuum bag\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eNylon 6\u0026ndash;6\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003ePeel ply\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003ePolyethylene terephthalate, granulate\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eInfusion mesh\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003ePolypropylene, granulate\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eTacky tape\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eSynthetic rubber\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eAspiration tubes\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eNylon 6\u0026ndash;6\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eVacuum hose\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003ePolypropylene, granulate\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eValves, spiral tubing, etc\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003ePolypropylene, granulate\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003c/tbody\u003e\n\u003c/table\u003e\n\u003c/div\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec6\" class=\"Section3\"\u003e\n\u003ch2\u003e2.2.2 End-of-life processes- Recycling processes\u003c/h2\u003e\n\u003cp\u003e\u003cstrong\u003eMechanical recycling.\u003c/strong\u003e Mechanical recycling of composites focuses on reducing the size of waste components for reuse in new materials (Pimenta and Pinho \u003cspan class=\"CitationRef\"\u003e2011\u003c/span\u003e). The recycling process typically starts with a primary crushing phase, where CFRPs are reduced in size to pieces about 50\u0026ndash;100 mm. The next step involves secondary grinding, carried out using hammer mills or high-speed mills, which reduces the material into finer particles, generally ranging from 10 mm to under 50 \u0026micro;m (Pickering \u003cspan class=\"CitationRef\"\u003e2006\u003c/span\u003e; Palmer et al. \u003cspan class=\"CitationRef\"\u003e2009\u003c/span\u003e). The output of the recycling process consists of 24 wt% fine fibers, 19 wt% fine powders, and 57 wt% coarse recyclate (Palmer et al. \u003cspan class=\"CitationRef\"\u003e2010\u003c/span\u003e). The fine fibers can be repurposed as reinforcement in new composite materials by partially replacing raw fiber. However, there is a limit to the amount of rCF that can be used before the mechanical properties of the composite begin to degrade significantly (Pickering \u003cspan class=\"CitationRef\"\u003e2006\u003c/span\u003e). Material losses are common during the mechanical recycling of CFRP waste. Typically, about 10% of the original CFRP waste input is lost, mainly due to the steps of size reduction and grinding. The total energy demand for CFRP recycling in this process involves two stages: shredding and mechanical milling. The shredding stage requires 0.27 MJ/kg, while the next stage of mechanical milling has an energy demand of 2.03 MJ/kg based on (Howarth et al. \u003cspan class=\"CitationRef\"\u003e2014\u003c/span\u003e). This calculation for grinding is based on industrial grinding with a feed hopper with a processing rate of 10 kg/hour. Figure\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003e provides a detailed flowchart of the mechanical recycling process.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003ePyrolysis.\u003c/strong\u003e Pyrolysis is a widely studied thermal recycling process for composites, where materials are heated in the absence or presence of oxygen, and more recently, in steam (Oliveux et al. \u003cspan class=\"CitationRef\"\u003e2015\u003c/span\u003e). This method breaks down the resin matrix into oils, gases, and solid residues, including fibers that may require cleaning to remove char (Cunliffe and Williams \u003cspan class=\"CitationRef\"\u003e2003\u003c/span\u003e). Post-treatment at high temperatures (450\u0026ndash;1300\u0026deg;C) can effectively clean the fibers but risks degrading their mechanical properties. Carbon fibers retain better properties depending on the pyrolysis conditions, balancing resin removal and fiber integrity (Meyer et al. \u003cspan class=\"CitationRef\"\u003e2009\u003c/span\u003e). The CFRP waste is first shredded using a mechanical mill using energy requirements data based on (Howarth et al. \u003cspan class=\"CitationRef\"\u003e2014\u003c/span\u003e). Pyrolysis, a thermal decomposition process, occurs in the absence of oxygen or with controlled oxygen flow at temperatures between 300\u0026deg;C and 800\u0026deg;C. Nitrogen is also used to prevent the oxidation of carbon fibers. Gases from resin degradation are collected, while solid residues (char) are usually disposed of in landfills. Energy consumption for recovering 1 kg of carbon fiber is estimated at approximately 30 MJ, producing rCF, ash, and emissions to the air (Witik et al. \u003cspan class=\"CitationRef\"\u003e2012\u003c/span\u003e). The LCI data are from (Meng et al. \u003cspan class=\"CitationRef\"\u003e2018\u003c/span\u003e) with nitrogen input referenced from(Lefeuvre et al. \u003cspan class=\"CitationRef\"\u003e2017\u003c/span\u003e). Figure\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e4\u003c/span\u003e provides the flowchart.\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eSolvolysis.\u003c/strong\u003e Chemical recycling involves the depolymerization of polymer matrices using specific chemical solvents. This process recovers clean fibers, and matrix material, which can be transformed into monomers or petrochemical feedstocks. Known as solvolysis, the method varies by solvent type, including hydrolysis (water), glycolysis (glycols), etc. High temperatures and pressures are often applied under subcritical or supercritical conditions for faster, more efficient dissolution (Dang et al. \u003cspan class=\"CitationRef\"\u003e2005\u003c/span\u003e). The experimental setup involved a high-pressure, high-temperature reactor, where CFRP samples were treated with supercritical and subcritical water. The solvent was chosen for its environmental benefits, availability, and low toxicity (Vogiantzi and Tserpes \u003cspan class=\"CitationRef\"\u003e2023\u003c/span\u003e). In this process, CFRP waste is placed in the reactor without pre-shredding, as the reactor size is designed to accommodate the desired fiber length. Water is pressurized to about 250 bars for supercritical water and 170 bars for subcritical water. The temperatures are 380\u0026deg;C and 350\u0026deg;C respectively. Water consumption is approximately 10 L/kg of CFRP (Pillain et al. \u003cspan class=\"CitationRef\"\u003e2019\u003c/span\u003e). Energy requirements are calculated based on the water's heat capacity. To determine the energy required to heat the water, considering that heat capacity is not constant ([CSL STYLE ERROR: reference with no printed form.]), the equation is expressed as:\u003c/p\u003e\n\u003cdiv id=\"Equ1\" class=\"Equation\"\u003e\n\u003cdiv id=\"FileID_Equ1\" class=\"mathdisplay\"\u003e$$\\:Q=m{\\int\\:}_{{T}_{1}}^{{T}_{2}}{c}_{p}dT.$$\u003c/div\u003e\n\u003cdiv class=\"EquationNumber\"\u003e1\u003c/div\u003e\n\u003c/div\u003e\n\u003cp\u003eHere, \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:Q\\)\u003c/span\u003e\u003c/span\u003e is the energy required (J), \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:m\\)\u003c/span\u003e\u003c/span\u003e is the mass of water (kg), \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:{T}_{1}\\)\u003c/span\u003e\u003c/span\u003e is the ambient temperature in \u0026deg;C, \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:{T}_{2}\\)\u003c/span\u003e\u003c/span\u003e is the desired temperature of the experiment in \u0026deg;C and \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:{c}_{p}\\)\u003c/span\u003e\u003c/span\u003e is the heat capacity (J/kg\u0026deg;C), which varies with temperature. This integral accounts for the changing value of \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:{c}_{p}\\)\u003c/span\u003e\u003c/span\u003e between 20\u0026deg;C and 380\u0026deg;C for the supercritical solvolysis and between 20\u0026deg;C and 380\u0026deg;C for the subcritical solvolysis. After calculating the energy requirements (approximately) for both supercritical and subcritical solvolysis, the results are presented in Fig.\u0026nbsp;5 (a) and Fig.\u0026nbsp;5 (b), respectively. These figures illustrate the input and output flows of each process. In this study, it is assumed that all water used during the solvolysis process is treated as waste, with no evaporation considered. Additionally, the entire quantity of the epoxy matrix is considered resin waste, as its recovery or reuse is not included within the scope of this analysis.\u003c/p\u003e\n\u003cdiv class=\"gridtable\"\u003e\u0026nbsp;\u003c/div\u003e\n\u003cp\u003e\u003cstrong\u003eHigh Voltage Fragmentation.\u003c/strong\u003e High-voltage fragmentation (HVF) is a recycling process that uses electrical discharges to break down materials. High-voltage pulses are generated by a Marx generator, creating plasma channels in a water-filled vessel between electrodes (Roux et al. \u003cspan class=\"CitationRef\"\u003e2017\u003c/span\u003e). These plasma channels produce intense energy, high pressures, and shock waves, leading to cracks and fragmentation in the material, especially in weaker components (Bluhm et al. \u003cspan class=\"CitationRef\"\u003e1997\u003c/span\u003e). Water is the dielectric medium due to its low cost, availability, and environmental advantages (Roux et al. \u003cspan class=\"CitationRef\"\u003e2017\u003c/span\u003e). The process decomposes the materials through repeated pulses, eventually fragmenting the CFRP. The process for high-voltage shredding recycling starts by shredding the CFRP waste into smaller pieces. These shreds are processed in a high-voltage fragmentation system, where deionized water acts as a dielectric medium. During the process, nitrogen is used to create the optimal conditions for effective fragmentation. Afterward, the treated material undergoes filtration to separate and recover the fragmented CFs for further utilization. The filters used can be reused, therefore, they are excluded from consideration in the LCA and LCC. The data for this HVF process are based on findings from the study conducted by (Pillain et al. \u003cspan class=\"CitationRef\"\u003e2019\u003c/span\u003e), which details the energy consumption, operational parameters, and mass balance. The HVF recycling process is illustrated in Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e4\u003c/span\u003e.\u003c/p\u003e\n\u003cp\u003eIn some recycling processes, such as solvolysis, the fibers require cleaning and oven drying to eliminate humidity. However, the consumption of water or solvents such as acetone for cleaning and the energy consumption of the drying oven are not included in the calculation.\u003c/p\u003e\n\u003c/div\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec7\" class=\"Section2\"\u003e\n\u003ch2\u003e2.3 Life cycle impact assessment\u003c/h2\u003e\n\u003cp\u003eIn this study, the environmental impacts and costs of recycling CFRP waste and the production of CFRP are assessed using the SimaPro 9.6.01 software with the ecoinvent 3 database. The methods selected for LCA are Cumulative Energy Demand (CED), IPCC 2021 GWP100, and ReCiPe Endpoint. These methodologies enable the comprehensive assessment of energy use, climate change potential (in kg CO₂-eq over a 100-year horizon), and endpoint-level damage to ecosystems, human health, and resource depletion.\u003c/p\u003e\n\u003cp\u003eFor the LCC analysis, the method proposed by SimaPro was developed. This approach includes economic data within the LCA framework to evaluate the costs associated with the different recycling processes and CFRP production. The methodology includes cost categories such as operational costs, which cover energy and material costs, and integrates them into the life cycle stages to provide an economic assessment.\u003c/p\u003e\n\u003c/div\u003e"},{"header":"3. Results","content":"\u003cp\u003eThe final phase of LCA is the interpretation of the results. This phase evaluates the findings from the LCI and LCIA stages, providing an analysis of the environmental impacts of the studied scenarios. This is followed by the LCC, where the economic aspects of the same scenarios are assessed. Below, the interpretation of the results is presented.\u003c/p\u003e\n\u003cdiv id=\"Sec9\" class=\"Section2\"\u003e\n\u003ch2\u003e3.1. Interpretation of LCA results\u003c/h2\u003e\n\u003cp\u003eAfter completing the LCA, the CED for producing 1kg of vCFs was calculated to be 747 MJ, while the GWP was determined to be 34.3 kg CO₂-eq.\u0026nbsp;Additionally, a tree diagram illustrating the process of vCFs production is provided in Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e7\u003c/span\u003e. The red lines in the tree diagram represent flow indicators, with line thickness corresponding to the environmental impact of each process stage. PAN production has a significant environmental footprint due to high electricity requirements and extensive use of chemicals such as AN.\u003c/p\u003e\n\u003cp\u003eAfterward, we evaluate the manufacturing of the CFRP plate with consumables using the LRI technique. The CED method is applied to analyze the electricity consumption for CFRP production, and the GWP is calculated to assess the carbon footprint of the process. The CED analysis (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e8\u003c/span\u003e) indicates that the production of vCFs has the highest impact on energy consumption. For this calculation, average electricity consumption data for Europe were used. However, it is important to note that this amount is likely to vary in different geographical areas due to differences in energy sources and efficiency.\u003c/p\u003e\n\u003cp\u003eThe total GWP is 25.2 kg CO₂eq, comprising:\u003c/p\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cp\u003e23.3 kg CO₂eq from UD fabric production, reflecting the high impact of the carbon fiber production stage,\u003c/p\u003e\n\u003c/li\u003e\n\u003cli\u003e\n\u003cp\u003e1.31 kg CO₂eq from epoxy resin production, and\u003c/p\u003e\n\u003c/li\u003e\n\u003cli\u003e\n\u003cp\u003e0.624 kg CO₂eq from consumables such as vacuum bags.\u003c/p\u003e\n\u003c/li\u003e\n\u003c/ul\u003e\n\u003cp\u003eAlso, an evaluation of the damage assessment using the Recipe Endpoint method is depicted in Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e9\u003c/span\u003e. The results highlight the relative contributions of CFRP and consumables to environmental impacts, measured in points (Pt). It is important to note that the waste of consumables category does not contribute to the environmental impact in this analysis, as the waste is simply considered as discarded material with no further treatment applied such as landfill. The impacts are categorized into three areas: human health, ecosystems, and resources. The main impact is due to the manufacturing of CFRP itself, which significantly outweighs the contribution of consumables and waste. Specifically, the human health category is most affected by CFRP, due to the energy-intensive processes involved.\u003c/p\u003e\n\u003cp\u003eTo enable the comparison of the recycling methods, Table\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003e presents the CED and GWP values for each process. Only the impacts of energy requirements and materials used during recycling processes are considered. Energy consumption associated with waste treatment, such as wastewater or epoxy resin waste management and potential energy recovery are excluded. Including these factors could reveal potential energy gain or revenue from energy recovery. Therefore, the focus remains on the energy inputs and material use during recycling processes.\u003c/p\u003e\n\u003cdiv class=\"gridtable\"\u003e\n\u003cdiv class=\"colspec\" align=\"left\"\u003e\u0026nbsp;\u003c/div\u003e\n\u003ctable id=\"Tab3\" border=\"1\"\u003e\u003ccaption\u003e\n\u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e\n\u003cdiv class=\"CaptionContent\"\u003e\n\u003cp\u003eCED and GWP of recycling for recycling processes\u003c/p\u003e\n\u003c/div\u003e\n\u003c/caption\u003e\n\u003cthead\u003e\n\u003ctr\u003e\n\u003cth align=\"left\"\u003e\n\u003cp\u003eRecycling process\u003c/p\u003e\n\u003c/th\u003e\n\u003cth align=\"left\"\u003e\n\u003cp\u003eCED (MJ/kg CFRP waste)\u003c/p\u003e\n\u003c/th\u003e\n\u003cth align=\"left\"\u003e\n\u003cp\u003eGWP (kg CO₂eq/kg CFRP waste)\u003c/p\u003e\n\u003c/th\u003e\n\u003c/tr\u003e\n\u003c/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eMechanical recycling\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e5.82\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.218\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003ePyrolysis\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e66.3\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e2.84\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eSolvolysis-subcritical water\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e49.8\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e1.87\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eSolvolysis-supercritical water\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e66.3\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e2.49\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eHVF\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e4.97\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"char\" char=\".\"\u003e\n\u003cp\u003e0.0796\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003c/tbody\u003e\n\u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003eRecycling processes have significantly lower energy consumption and carbon footprints compared to vCFs production. Among the recycling methods, mechanical recycling and HVF exhibit the lowest CED and GWP values, primarily due to their minimal energy requirements. In contrast, pyrolysis and supercritical water solvolysis require substantial energy inputs, with pyrolysis relying on natural gas, and solvolysis needing high energy to surpass the critical point of water and reach the required 380\u0026deg;C temperature for processing. Additionally, an evaluation of the damage assessment for the different recycling methods is presented (Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e10\u003c/span\u003e). \u0026Mu;echanical recycling and HVF show minimal impacts in all categories, benefiting human health and resources in particular. In contrast, pyrolysis and solvolysis with supercritical water have significant negative effects on human health and ecosystems. Pyrolysis, in particular, has significant environmental impacts, especially in terms of resources. Solvolysis with subcritical water, however, has more balanced environmental impacts.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec10\" class=\"Section2\"\u003e\n\u003ch2\u003e3.2. LCC results\u003c/h2\u003e\n\u003cp\u003eIn the LCC, only material and energy costs are considered. The country of material production is considered; however, transportation costs are excluded from the analysis. Material costs are obtained from suppliers selling these materials, while energy costs are based on the average energy price in Europe ([CSL STYLE ERROR: reference with no printed form.]). The LCC data inventory for materials and energy costs associated with manufacturing CFRP plate is detailed in Table\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e4\u003c/span\u003e, with costs presented in \u0026euro;/kg for each input. It accounts for the total cost of producing carbon fiber, epoxy resin, and consumables. These costs are relatively high, as the calculation is based on the production of a single kilogram rather than mass production, where economies of scale would reduce costs. Additionally, the analysis considers raw material and energy costs, not the market price of finished products like carbon fiber. After calculations, the total cost for producing 1 kg of CFRP is 211\u0026euro;.\u003c/p\u003e\n\u003cdiv class=\"gridtable\"\u003e\n\u003cdiv class=\"colspec\" align=\"left\"\u003e\u0026nbsp;\u003c/div\u003e\n\u003ctable id=\"Tab4\" border=\"1\"\u003e\u003ccaption\u003e\n\u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e\n\u003cdiv class=\"CaptionContent\"\u003e\n\u003cp\u003eLCI of costs for materials and energy for the production of CFRP\u003c/p\u003e\n\u003c/div\u003e\n\u003c/caption\u003e\n\u003cthead\u003e\n\u003ctr\u003e\n\u003cth align=\"left\"\u003e\n\u003cp\u003eInput\u003c/p\u003e\n\u003c/th\u003e\n\u003cth align=\"left\"\u003e\n\u003cp\u003eImpact category\u003c/p\u003e\n\u003c/th\u003e\n\u003cth align=\"left\"\u003e\n\u003cp\u003eFactor\u003c/p\u003e\n\u003c/th\u003e\n\u003cth align=\"left\"\u003e\n\u003cp\u003eUnit\u003c/p\u003e\n\u003c/th\u003e\n\u003c/tr\u003e\n\u003c/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eUD production\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eMaterial costs\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e246\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e\u0026euro;/kg\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eEpoxy resin\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eMaterial costs\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e100\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e\u0026euro;/kg\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eConsumables\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eMaterial costs\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e16.5\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e\u0026euro;/kg\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003ctr\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eElectricity\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003eEnergy costs\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e0.052\u003c/p\u003e\n\u003c/td\u003e\n\u003ctd align=\"left\"\u003e\n\u003cp\u003e\u0026euro;/MJ\u003c/p\u003e\n\u003c/td\u003e\n\u003c/tr\u003e\n\u003c/tbody\u003e\n\u003c/table\u003e\n\u003c/div\u003e\n\u003cp\u003eFor the recycling processes, only the material and energy costs associated with the operational aspects of the methods were considered. These include the inputs and energy consumed during the recycling stages. However, potential revenue from recycled carbon fibers (rCFs) could also be factored in (not included in this analysis). If the quality and mechanical properties of the recycled fibers are sufficient, they can be reused. This could offset part of the recycling costs. As a result, reusing recycled fibers can contribute positively to the overall economic viability of the processes. In Fig.\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e11\u003c/span\u003e, the material and energy costs for each recycling process are displayed, offering a detailed overview of the costs associated with each method. In mechanical recycling and pyrolysis, the materials costs are either negligible or zero. However, for solvolysis and HVF, the primary material cost comes from deionized water. Regarding energy costs, pyrolysis stands out with the highest cost due to its significant energy demands. Solvolysis with supercritical water follows as it requires considerable energy to heat the water to 380\u0026deg;C. The total cost for each recycling process is as follows: mechanical recycling costs 0.106 \u0026euro;/kg CFRP waste, pyrolysis costs 4.66 \u0026euro;/kg, solvolysis with subcritical water costs 50.9 \u0026euro;/kg, solvolysis with supercritical water costs 51.2 \u0026euro;/kg, and HVF costs 155 \u0026euro;/kg.\u003c/p\u003e\n\u003cp\u003e\u0026nbsp;\u003c/p\u003e\n\u003c/div\u003e"},{"header":"4. Discussion","content":"\u003cp\u003eThis paper discusses four recycling methods for CFRP, including the three main recycling methods and one innovative approach (HVF). When assessing these methods, it is important to consider both environmental impacts and cost factors such as capital and operational costs. However, the quality of the recycled fibers also plays a critical role - if the quality of the fibers is poor, recycling may not be viable. In addition, the technology readiness levels of these methods (TRL) vary. Mechanical recycling and pyrolysis are at a high TRL, which makes them ready for use on an industrial scale, while the other methods are still in the laboratory scale phase (Rybicka et al. \u003cspan citationid=\"CR42\" class=\"CitationRef\"\u003e2016\u003c/span\u003e). This difference highlights the challenge of scaling up recycling processes from small samples or parts to complete structures.\u003c/p\u003e \u003cp\u003eA significant limitation of this study is the assumption that the fibers are perfectly recycled, 100% clean, and resin-free. In reality, this is not always the case, and additional steps are often required to ensure the fibers are thoroughly cleaned. These additional steps inevitably contribute to environmental impacts and economic costs, yet they are challenging to quantify and integrate into the study. Furthermore, chemical recycling, particularly solvolysis, remains an evolving field. This method allows for a diverse selection of solutions and process parameters, including temperature, pressure, and reaction time (Utekar et al. \u003cspan citationid=\"CR48\" class=\"CitationRef\"\u003e2021\u003c/span\u003e). To evaluate solvolysis effectively, it is essential to optimize process parameters to achieve a balance among mechanical properties, environmental impact, and cost efficiency.\u003c/p\u003e \u003cp\u003eFurthermore, only the costs of materials and energy used in the recycling processes have been considered in this study. Potential costs or revenues associated with waste, recycled fibers, and possible energy recovery from these processes have not been included. The integration of these factors could provide a more complete estimate of total costs. For instance, (Shehab et al. \u003cspan citationid=\"CR43\" class=\"CitationRef\"\u003e2021\u003c/span\u003e) categorize costs into dismantling, transportation, operation, and capital and present a fuzzy logic-based system for estimating the recycling costs of CFRPs. Depending on the perspective of the study, recycling methods could be evaluated as a service, with the cost of providing this service being included in the analysis.\u003c/p\u003e \u003cp\u003eLast but not least, the most important limitation of this study is that the LCI data used for the assessment comes from various sources, including literature, experiments, and industry reports. As a result, the materials analyzed in each recycling method differ, which could impact the results. Specifically, although the study focuses on epoxy resin, the data used is derived from different types of epoxy resins. Thus, variations in the chemical formulation of the resins might affect their environmental impacts. Therefore, a more reliable comparison of recycling processes would require the use of the same material (CFRP) and quantity across all methods. Additionally, input and energy requirements should be consistently calculated for each process to ensure an accurate assessment of their environmental impacts and operational costs.\u003c/p\u003e"},{"header":"4. Conclusions","content":"\u003cp\u003eThis paper evaluates the production of vCFs and the manufacturing of CFRPs using the LRI method. Additionally, it compares three conventional CFRP recycling methods\u0026mdash;mechanical recycling, pyrolysis, and solvolysis\u0026mdash;alongside an innovative approach, HVF. A comprehensive cost analysis of material and energy requirements accompanies these comparisons.\u003c/p\u003e \u003cp\u003eThe LCA indicates that mechanical recycling is the most environmentally friendly and cost-effective method, with the lowest energy consumption and carbon footprint. Conversely, pyrolysis and solvolysis are associated with significantly higher energy demands and environmental impacts. Nevertheless, the preservation of carbon fiber mechanical properties should be incorporated into future assessments, ensuring the alignment of environmental and economic analyses with fiber reuse potential.\u003c/p\u003e \u003cp\u003eThe study is limited by assumptions such as complete resin decomposition, which may impact accuracy. Future research should aim to standardize CFRP across recycling methods, investigate energy recovery opportunities, and examine factors influencing the quality and reuse potential of recycled fibers.\u003c/p\u003e "},{"header":"Declarations","content":"\u003cp\u003e \u003cb\u003eCRediT authorship contribution statement\u003c/b\u003e \u003c/p\u003e \u003cp\u003eKonstantinos Tserpes: Methodology, Writing - review \u0026amp; editing, Conceptualization, Supervision. Christina Vogiantzi: Methodology, Writing - original draft, Software, Investigation, Visualization.\u003c/p\u003e\u003cp\u003e \u003ch2\u003eDeclaration of competing interest\u003c/h2\u003e \u003cp\u003eThe authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.\u003c/p\u003e \u003c/p\u003e\u003ch2\u003eData availability\u003c/h2\u003e \u003cp\u003eData will be made available on request.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eAldosari SM, AlOtaibi BM, Alblalaihid KS et al (2024) Mechanical Recycling of Carbon Fiber-Reinforced Polymer in a Circular Economy. 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Accessed 27 Nov 2024c\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Carbon fiber reinforced plastics, Recycling, Life cycle assessment, Life cycle costing","lastPublishedDoi":"10.21203/rs.3.rs-5626810/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-5626810/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eThe growing adoption of Carbon Fiber Reinforced Polymers (CFRPs) in advanced structural applications has emphasized the need for sustainable recycling methods to address environmental and economic challenges associated with end-of-life (EoL) management. While CFRPs offer exceptional specific mechanical properties, their thermosetting matrix complicates recycling efforts, often resulting in energy-intensive disposal or significant waste accumulation. In recent years, considerable advancements have been made in CFRP recycling, with three primary processes emerging: mechanical, thermal, and chemical recycling. Existing comparisons of these methods have focused on the mechanical performance of recovered fibers, yet their broader sustainability implications warrant further exploration. This study undertakes a comprehensive Life Cycle Assessment (LCA) and Environmental Life Cycle Costing (eLCC) analysis of four key recycling techniques: mechanical recycling, pyrolysis, solvolysis, and high-voltage fragmentation. The analysis encompasses the metrics of cumulative energy demand, global warming potential, damage assessment by the Recipe endpoint method, and cost. In the analysis, available data from the literature, process models, and experimental and manufacturing procedures were used. The study's findings emphasize that CFRP recycling methods significantly reduce energy consumption and carbon footprints compared to the production of virgin fibers. Among the recycling techniques evaluated, mechanical recycling and high-voltage fragmentation demonstrate the lowest environmental impact, contributing positively to human health and the preservation of natural resources. The results enable the informed selection of sustainable and cost-effective CFRP recycling processes, supporting advancements in sustainable manufacturing and end-of-life product management.\u003c/p\u003e","manuscriptTitle":"A Comparative Environmental and Economic Analysis of CFRP Recycling Processes Using Life Cycle Assessment and Life Cycle Costing","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-12-13 06:52:59","doi":"10.21203/rs.3.rs-5626810/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"6ae6fd7b-02f2-4c34-a96e-17cfe7180b22","owner":[],"postedDate":"December 13th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2024-12-13T06:52:59+00:00","versionOfRecord":[],"versionCreatedAt":"2024-12-13 06:52:59","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-5626810","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-5626810","identity":"rs-5626810","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}