Journal of Composites Science

Research

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13 pages, 4156 KiB

Open AccessArticle

Transformation of Biomass Power Plant Ash into Composite Fertilizers: A Perspective to Prepare a Rain-Controlled Ammonium Ion–Releasing Composite Fertilizer

by László Kótai, Márk Windisch and Kende Attila Béres

J. Compos. Sci. 2024, 8(9), 336; https://doi.org/10.3390/jcs8090336 - 24 Aug 2024

Viewed by 796

Abstract

We have developed a convenient route to transform biomass power plant ashes (BPPA) into porous sponge-like fertilizer composites. The absence of water prevents the chemical reaction and carbon dioxide formation when concentrated sulfuric acid is mixed with BPPA and CaCO₃. Adding [...] Read more.

We have developed a convenient route to transform biomass power plant ashes (BPPA) into porous sponge-like fertilizer composites. The absence of water prevents the chemical reaction and carbon dioxide formation when concentrated sulfuric acid is mixed with BPPA and CaCO₃. Adding water, however, initiates the protonation reaction of carbonate ion content and starts CO₂ evolution. The key element of the method was that the BPPA and, optionally, CaCO₃ and/or CaSO₄·0.5H₂O were mixed with concentrated sulfuric acid to make a paste-like consistency. No gas evolution occurred at this stage; however, with the subsequent and controlled addition of water, CO₂ gas evolved and was released through the channels developed in the pastry-like material due to the internal gas pressure, but without foaming. Using a screw-containing tube reactor, the water can be introduced under pressure. Due to the pressure, the pores in the pastry-like material became smaller, and consequently, the mechanical strength of the granulated and solidified mixture became higher than that of the reaction products prepared under atmospheric pressure. The main reaction products were syngenite (K₂Ca(SO₄)₂·H₂O) and polyhalite (K₂Ca₂Mg(SO₄)₄·2H₂O). These compounds are valuable fertilizer components in themselves, but the material’s porous nature helps absorb solutions of microelement fertilizers. Surprisingly, concentrated ammonium nitrate solutions transform the syngenite content of the porous fertilizer into ammonium calcium sulfate ((NH₄)₂Ca(SO₄)₂·2H₂O, koktaite). Koktaite is slightly soluble in water, thus the amount of ammonium ion released on the dissolution of koktaite depends on the amount of available water. Accordingly, ammonium ion release for plants can be increased with rain or irrigation, and koktaite is undissolved and does not decompose in drought situations. The pores (holes) of this sponge-like fertilizer product can be filled with different solutions containing other fertilizer components (phosphates, zinc, etc.) to adjust the composition of the requested fertilizer compositions for particular soils and plant production. The method allows the preparation of ammonium nitrate composite fertilizers containing metallic microelements, and various solid sponge-like composite materials with adjusted amounts of slowly releasing fertilizer components like syngenite and koktaite. Full article

(This article belongs to the Special Issue From Waste to Advance Composite Materials)

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15 pages, 6785 KiB

Open AccessArticle

Comprehensive Utilization of Fossil Energy: Fabrication of Fire-Retardant Building Materials from Waste Plastic

by Zheng Wang, Long Geng, Jiateng Zhao, Wenyuan Qiao and Changhui Liu

J. Compos. Sci. 2024, 8(7), 266; https://doi.org/10.3390/jcs8070266 - 10 Jul 2024

Viewed by 888

Abstract

As one of the most common fossil derivatives, plastics are widely used for their exceptional chemical stability, low density, and ease of processing. In recent years, there has been a significant increase in the production of waste plastics, coupled with a low recycling [...] Read more.

As one of the most common fossil derivatives, plastics are widely used for their exceptional chemical stability, low density, and ease of processing. In recent years, there has been a significant increase in the production of waste plastics, coupled with a low recycling rate, resulting in serious environmental pollution. To enhance the use of waste plastics, this research synthesized flame-retardant materials from hypercrosslinked polystyrene with different molar fractions of flame retardants. Waste polystyrene foam was used as the raw material, while aniline, triphenylphosphine, and melamine were employed as flame-retardant additives. The flame-retardant additives were successfully doped into the porous skeleton structure of hypercrosslinked polystyrene through a chemical reaction or physical mixing to achieve in situ flame retardancy, and the materials were shaped by a phenolic resin prepolymer. Then, the samples were characterized in detail, and the results indicate that the addition of a flame retardant enhances the flame retardancy of the material. In addition, the material has excellent thermal insulation performance, with a minimum thermal conductivity of 0.04176 W/(m·K). Full article

(This article belongs to the Special Issue From Waste to Advance Composite Materials)

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19 pages, 19740 KiB

Open AccessArticle

Composite Materials with Glass Fiber Waste and Blast Furnace Slag

by Mihaela Fanache, Leonid Vasiliu and Maria Harja

J. Compos. Sci. 2024, 8(7), 256; https://doi.org/10.3390/jcs8070256 - 2 Jul 2024

Viewed by 998

Abstract

Fiberglass is a waste generated in the construction materials industry, which is not dangerous for the environment, but long-term and very long-term storage is expensive. Finding a method of reuse as in creating a useful composite material led to the research work in [...] Read more.

Fiberglass is a waste generated in the construction materials industry, which is not dangerous for the environment, but long-term and very long-term storage is expensive. Finding a method of reuse as in creating a useful composite material led to the research work in this study. The impact of waste fiberglass and furnace slag on the characteristics of novel composite materials was examined in this study. The density and mechanical properties of the composite samples were examined to determine the impact of waste fiberglass (WFG) concentration in it. Washed river aggregates were replaced with WFG in various ratios in our laboratory tests. Concrete class C16/20 was utilized, having 0.35–0.7 w. % WFG and 2–10% slag. The obtained material was evaluated for density, workability, and compressive strength. The experiments were carried out in an accredited concrete station laboratory. The density of the resulting materials decreased as the WFG content was increased. The densities were higher than the witness sample, ranging from 2358 to 2405 kg/m³. The findings show that adding WFG and slag to concrete has a positive impact on its characteristics. With the addition of WFG, the mixture became more non-homogenous, but these characteristics can be optimized in future. Because of the differential in density between WFG and natural coarse aggregates, the fresh density of obtained composites dropped as the percentage of WFG increased; this could be an advantage, as the newly obtained material became lighter. The findings show that adding waste to concrete has a detrimental impact on its qualities. The introduction of blast furnace slag up to 5% does not modify the compressive strength, compared to the reference samples, but 10% slag causes a decrease in compressive strength of 4.2%. A proportion of 0.25% WFG causes a slight increase in mechanical strength; therefore, 0.25% WFG and 5% slag increased the compressive strength, the maximum value being obtained for a composite with 0.25% WFG, 5% slag, 5% sand and aggregates. Capitalization of WFG and slag resulted in significant economic and environmental benefits by reducing waste storage costs and production costs, and advantages resulted from the new material. Full article

(This article belongs to the Special Issue From Waste to Advance Composite Materials)

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16 pages, 5979 KiB

Open AccessArticle

Preparation and Characterization of Particleboard Made from Industrial-Type Wood Particles and Discarded Duck Feathers

by Nidal Del Valle Raydan, Bertrand Charrier, Grzegorz Kowaluk and Eduardo Robles

J. Compos. Sci. 2024, 8(7), 241; https://doi.org/10.3390/jcs8070241 - 25 Jun 2024

Cited by 1 | Viewed by 1416

Abstract

Global poultry waste production is substantial, with billions of poultry raised annually for meat and egg production, resulting in significant feather waste. Conventional poultry waste disposal methods are restricted due to environmental concerns. Meanwhile, wood-composite panel industries face raw material shortages, emphasizing the [...] Read more.

Global poultry waste production is substantial, with billions of poultry raised annually for meat and egg production, resulting in significant feather waste. Conventional poultry waste disposal methods are restricted due to environmental concerns. Meanwhile, wood-composite panel industries face raw material shortages, emphasizing the need for sustainable, renewable fiber sources. In this study, in the core layer of panels, wood particles were replaced with 5 wt% clean duck feathers without pretreatment to take advantage of feather attributes like hydrophobicity, thermal insulation, and sound damping as an alternative construction material. Three adhesives—urea-formaldehyde (UF), polymeric 4,4′-diphenylmethane diisocyanate (pMDI), and polyvinyl acetate (PVAc)—were examined for resin–feather compatibility. The control panels in this study were identical but wood was not replaced with feathers. The results revealed that wood–feather particleboard with pMDI and PVAc resins meets the requirements of the relevant standard for P2 boards (where applicable) concerning their modulus of rupture (MOR: 11 N·mm⁻²), modulus of elasticity (MOE: 1600 N·mm⁻²), internal bond (IB: 0.35 N·mm⁻²), and screw withdrawal resistance (SWR). However, those produced with UF resin did not meet the standards for IB and MOE. Furthermore, the physical properties showed similar water resistance and thickness swelling to control panels with pMDI. Notably, substituting 5 wt% wood with feathers improved thermal insulation by approximately 10% for UF and pMDI resins. Additionally, particleboard with feathers demonstrated improved sound absorption at high frequencies, ranging from 2500 to 500 Hz, particularly with pMDI resin, approaching Class B classification according to EN ISO 11654:1997. This study identifies the higher compatibility of pMDI over PVAc and UF adhesives for feather-based composite materials in construction applications. Full article

(This article belongs to the Special Issue From Waste to Advance Composite Materials)

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15 pages, 11738 KiB

Open AccessArticle

Gypsum Composites with Modified Waste Expanded Polystyrene

by Pauls P. Argalis, Girts Bumanis and Diana Bajare

J. Compos. Sci. 2023, 7(5), 203; https://doi.org/10.3390/jcs7050203 - 18 May 2023

Cited by 6 | Viewed by 1729

Abstract

The construction and demolition waste recycling into secondary raw materials is vital to achieving a sustainable and circular building life cycle. Expanded polystyrene (EPS) is one of the materials whose recycling rate should be increased. EPS boards can be shredded and used as [...] Read more.

The construction and demolition waste recycling into secondary raw materials is vital to achieving a sustainable and circular building life cycle. Expanded polystyrene (EPS) is one of the materials whose recycling rate should be increased. EPS boards can be shredded and used as aggregate of lightweight cement composites resulting in a material with combined properties subjected from EPS and mineral binder. To reduce the open structure of shredded EPS particles, proper treatment could improve EPS performance. The heat treatment of the aggregates can reduce the volume and increase their density. In this paper, EPS aggregates were heat-treated at 120 and 130 °C, and heat-modified EPS aggregates with a bulk density of 40 and 100 kg/m³ were incorporated as filler material in gypsum composites. The composites’ density, compressive strength, thermal conductivity, and sound absorption were characterized. Results indicate that a composite with a compressive strength from 15 to 136 kPa and a material density ranging from 48 to 194 kg/m³ can be obtained. Thermal conductivity was achieved from 0.0390 to 0.0604 W/(mK). Following the ISO 10534-2 standard, the noise reduction coefficient was determined and showed promising results at 600 to 800 Hz, reaching a sound absorption coefficient of 0.88. Full article

(This article belongs to the Special Issue From Waste to Advance Composite Materials)

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10 pages, 3175 KiB

Open AccessArticle

Study on the Direct Transformation of Milk Bottle and Wood into Wood–Plastic Composite through Injection Molding

by Md. Shahruk Nur-A-Tomal, Farshid Pahlevani and Veena Sahajwalla

J. Compos. Sci. 2022, 6(8), 230; https://doi.org/10.3390/jcs6080230 - 5 Aug 2022

Cited by 2 | Viewed by 2150

Abstract

Plastic has transformed the world; however, it generates a huge amount of waste plastics. It is well evident that, if urgent action is not undertaken on plastic pollution, it will pose threats to not only the environment, but also human life. Just simply [...] Read more.

Plastic has transformed the world; however, it generates a huge amount of waste plastics. It is well evident that, if urgent action is not undertaken on plastic pollution, it will pose threats to not only the environment, but also human life. Just simply discarding waste plastics will result in wasting a lot of valuable materials that could be recycled. Recently, the use of waste plastics has been considered for producing wood plastic composites (WPCs), which are superior to normal wood. Waste plastics are pelletized using an extruder and are then subjected to injection molding. In this study, investigations were carried out to determine the possibility of producing WPCs without the palletization of waste plastic to turn WPC production into a shorter, simple, and easy-to-achieve process. Here, a waste milk bottle, a familiar single-use plastic, was picked as a case study. Waste plastic granules and wood particles were mixed and directly injection molded to produce valuable WPCs. The water absorption of WPCs with 20% wood is 0.35%, and this increased to 0.37% when wood content was increased to 40%. The tensile strength at yield, elongation at break, and impact strength of WPCs with 20% wood content are 19.54 MPa, 5.21%, and 33.92 KJ/m², respectively, whereas it was 17.23 MPa, 4.05%, and 26.61 KJ/m² for the WPCs with 40% wood content. This process can be a potential solution for two problematic wastes at the same time. Full article

(This article belongs to the Special Issue From Waste to Advance Composite Materials)

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14 pages, 1750 KiB

Open AccessArticle

Utilization of Wood Flour from White Oak Branches as Reinforcement in a Polypropylene Matrix: Physical and Mechanical Characterization

by José Angel Hernández-Jiménez, Rosa María Jiménez-Amezcua, María Guadalupe Lomelí-Ramírez, José Antonio Silva-Guzmán, José Guillermo Torres-Rendón and Salvador García-Enriquez

J. Compos. Sci. 2022, 6(7), 184; https://doi.org/10.3390/jcs6070184 - 22 Jun 2022

Cited by 6 | Viewed by 2177

Abstract

Compared to other fibrous materials, plant fibers can act as a reinforcement in plastics due to their relatively high strength and rigidity, low cost, low density, biodegradability, and renewability. In this context, this study examines the effect of the particle size and content [...] Read more.

Compared to other fibrous materials, plant fibers can act as a reinforcement in plastics due to their relatively high strength and rigidity, low cost, low density, biodegradability, and renewability. In this context, this study examines the effect of the particle size and content of white oak wood flour (Quercus laeta Liemb), obtained from its branches, on the properties of commercial polypropylene. In Mexico, wood from the branches of Quercus laeta Liemb is barely utilized despite its abundance and viability. The main objective of this study is to demonstrate that this waste material can be exploited to prepare useful materials, in this case composites with competitive properties. Tensile and flexural tests, as well as impact strength and melt flow index were evaluated. In addition, density and water absorption capacity were also tested. Results showed that the water absorption increased with the incorporation of wood particles. Mechanical properties were strongly influenced by particle content. A reduction in elongation and strength was observed, while Young’s modulus and flexural modulus increased with the incorporation of wood particles. Impact strength increased with particle size and particle content. Full article

(This article belongs to the Special Issue From Waste to Advance Composite Materials)

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19 pages, 4883 KiB

Open AccessArticle

Structural Changes and Their Implications in Foamed Flexible Polyurethane Composites Filled with Rapeseed Oil-Treated Ground Tire Rubber

by Paulina Kosmela, Adam Olszewski, Łukasz Zedler, Paulina Burger, Krzysztof Formela and Aleksander Hejna

J. Compos. Sci. 2021, 5(3), 90; https://doi.org/10.3390/jcs5030090 - 23 Mar 2021

Cited by 8 | Viewed by 2849

Abstract

The utilization of post-consumer car tires is an essential issue from an ecological and economic point of view. One of the simplest and the least harmful methods is their material recycling resulting in ground tire rubber (GTR), which can be further applied as [...] Read more.

The utilization of post-consumer car tires is an essential issue from an ecological and economic point of view. One of the simplest and the least harmful methods is their material recycling resulting in ground tire rubber (GTR), which can be further applied as fillers for polymer-based composites. Nevertheless, insufficient interfacial interactions implicate the necessity of GTR modification before introduction into polymer matrices. In this study, we investigated the influence of rapeseed oil-assisted thermo-mechanical treatment of GTR using a reactive extrusion process on the processing, structure, and performance of flexible polyurethane/GTR composite foams. Applied modifications affected the processing of polyurethane systems. They caused a noticeable reduction in the average cell size of foams, which was attributed to the potential nucleating activity of solid particles and changes in surface tension caused by the presence of oil. Such an effect was especially pronounced for the waste rapeseed oil, which resulted in the highest content of closed cells. Structural changes caused by GTR modification implicated the enhancement of foams’ strength. Mechanical performance was significantly affected by the applied modifications due to the changes in glass transition temperature. Moreover, the incorporation of waste GTR particles into the polyurethane matrix noticeably improved its thermal stability. Full article

(This article belongs to the Special Issue From Waste to Advance Composite Materials)

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Review

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23 pages, 6490 KiB

Open AccessReview

Modern Trends in Recycling Waste Thermoplastics and Their Prospective Applications: A Review

by Isiaka Oluwole Oladele, Christian Junior Okoro, Anuoluwapo Samuel Taiwo, Linus N. Onuh, Newton Itua Agbeboh, Oluwayomi Peter Balogun, Peter Apata Olubambi and Senzeni Sipho Lephuthing

J. Compos. Sci. 2023, 7(5), 198; https://doi.org/10.3390/jcs7050198 - 13 May 2023

Cited by 11 | Viewed by 6506

Abstract

Thermoplastics and thermosetting plastics are two major classes of polymers in that have recently become materials that are indispensable for humankind. Regarding the three basic needs of human beings—food, shelter, and clothing—polymers and polymer-based materials have gained pre-eminence. Polymers are used in food [...] Read more.

Thermoplastics and thermosetting plastics are two major classes of polymers in that have recently become materials that are indispensable for humankind. Regarding the three basic needs of human beings—food, shelter, and clothing—polymers and polymer-based materials have gained pre-eminence. Polymers are used in food production, beginning with farming applications, and in the health sector for the development of various biomaterials, as well as in shelter and clothing for a variety of applications. Polymers are the material of choice for all modern-day applications (transportation, sporting, military/defence, electronics, packaging, and many more). Their widespread applications have created many negative challenges, mainly in the area of environmental pollution. While thermoplastics can be easily reprocessed to obtain new products, thermosetting plastics cannot; thus, this review focuses more on the use of waste from thermoplastics with less emphasis on thermosetting plastics. Hence, the review presents a concise summary of the availability of waste thermoplastics as raw materials for product development and the anticipated benefits. The prospects for waste thermoplastics and thermosetting plastics, the possibility of cleaning the environment, and the uncovering of opportunities for further research and development are presented. The limitations of the current methods of waste polymer recycling are highlighted with possible future prospects from newly introduced methods. With zero tolerance for polymer waste in our environments, potential uses for recycled thermosetting plastics are described. Waste polymers should be seen as potential raw materials for research and development as well as major materials for new products. Recycled polymers are expected to be processed for use in advanced materials applications in the future due to their availability. This review shows that the major source of environmental pollution from polymers is the packaging, hence the need to modify products for these applications by ensuring that most of them are biodegradable. Full article

(This article belongs to the Special Issue From Waste to Advance Composite Materials)

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20 pages, 34692 KiB

Open AccessReview

Thermal Transformation of Secondary Resources of Carbon-Rich Wastes into Valuable Industrial Applications

by Sepideh Hemati, Sanjith Udayakumar, Charlotte Wesley, Smitirupa Biswal, Md. Shahruk Nur-A-Tomal, Negin Sarmadi, Farshid Pahlevani and Veena Sahajwalla

J. Compos. Sci. 2023, 7(1), 8; https://doi.org/10.3390/jcs7010008 - 3 Jan 2023

Cited by 6 | Viewed by 2468

Abstract

Carbon-based materials have become an indispensable component in a myriad of domestic and industrial applications. Most of the carbon-based end-of-life products discussed in this review end up in landfills. Where recycling is available, it usually involves the production of lower-value products. The allotropic [...] Read more.

Carbon-based materials have become an indispensable component in a myriad of domestic and industrial applications. Most of the carbon-based end-of-life products discussed in this review end up in landfills. Where recycling is available, it usually involves the production of lower-value products. The allotropic nature of carbon has been analysed to identify novel materials that could be obtained from used products, which also transform into a secondary carbon resource. Thermal transformation of carbon-rich wastes is a promising and viable pathway for adding value to waste that would otherwise go to landfills. The valorisation routes of four different carbon-rich wastes by thermal transformation are reviewed in the study—automotive shredder residue (ASR), textile wastes, leather wastes, and spent coffee grounds (SCGs). Textile wastes were thermally transformed into carbon fibres and activated carbon, while ASRs were used as a reductant to produce silicon carbide (SiC) from waste glass. The leather wastes and spent coffee grounds (SCGs) were employed as reductants in the reduction of hematite. This paper examines the possible routes of thermally transforming carbon-rich wastes into different industrial processes and applications. The transformation products were characterised using several techniques to assess their suitability for their respective applications. The strategy of valorising the wastes by thermal transformation has successfully prevented those wastes from ending up in landfills. Full article

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30 pages, 3272 KiB

Open AccessReview

Challenges and Impacts of COVID-19 Pandemic on Global Waste Management Systems: A Review

by Ismail Luhar, Salmabanu Luhar and Mohd Mustafa Al Bakri Abdullah

J. Compos. Sci. 2022, 6(9), 271; https://doi.org/10.3390/jcs6090271 - 14 Sep 2022

Cited by 23 | Viewed by 7203 | Correction

Abstract

Unfortunately, nearly the whole world came to a standstill due to the coronavirus disease 2019, i.e., the COVID-19 pandemic, which negatively and severely impacted almost all facets of society, systems, and lives on the planet during the last few years. During this time, [...] Read more.

Unfortunately, nearly the whole world came to a standstill due to the coronavirus disease 2019, i.e., the COVID-19 pandemic, which negatively and severely impacted almost all facets of society, systems, and lives on the planet during the last few years. During this time, a surge in the generation of a huge volume of diverse wastes at an unprecedented rate occurred due to the extensive use of disposables and personal shielding safety gear such as personal protective equipment (PPE) for both infected and uninfected people as well as frontline staff, etc., as corona protocols, especially in the form of “plastic wastes”. Consequently, all these factors induced a novel route for the pollution of air, soil, and water, inviting a great number of health hazards in addition to the pandemic. Beyond a doubt, the susceptibility of the spread of the coronavirus through polluted waste is high, an issue for which the waste management measures are comparatively not up to the mark. The spread of COVID-19 forced the world into lockdown, which had both constructive and unconstructive effects on not only the environment but also systems such as the waste management sector, etc. The unforeseen increase in the quantity of waste created a challenge concerning normal waste disposal facilities, negatively impacting the global waste management industry, and hence, leading to an urgent situation internationally. Still, in developing nations, the sector of waste management is at its nascent stage, and therefore, the sector of waste management during the pandemic period has been influenced severely in many parts of the world. The current comprehensive review provides not only an overview of the impacts and challenges of COVID-19 on the waste management sector but also extends the systematic data of waste generation that has been made accessible so far along with a discussion on the safety of the related workers and staff as well as suggestions for the possible approaches towards better waste management services, which are essential to manage the waste increase resultant of the COVID-19 pandemic in a majority of nations. Full article

(This article belongs to the Special Issue From Waste to Advance Composite Materials)

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30 pages, 5261 KiB

Open AccessEditor’s ChoiceReview

Recent Advances in Geopolymer Technology. A Potential Eco-Friendly Solution in the Construction Materials Industry: A Review

by Matteo Sambucci, Abbas Sibai and Marco Valente

J. Compos. Sci. 2021, 5(4), 109; https://doi.org/10.3390/jcs5040109 - 17 Apr 2021

Cited by 49 | Viewed by 7471

Abstract

In the last ten years, the Portland cement industry has received wide criticism due to its related high embodied energy and carbon dioxide footprint. Recently, numerous “clean” strategies and solutions were developed. Among these, geopolymer technology is gaining growing interest as a functional [...] Read more.

In the last ten years, the Portland cement industry has received wide criticism due to its related high embodied energy and carbon dioxide footprint. Recently, numerous “clean” strategies and solutions were developed. Among these, geopolymer technology is gaining growing interest as a functional way to design more eco-friendly construction materials and for waste management issues suffered by various industries. Previous research has highlighted the attractive engineering properties of geopolymeric materials, especially in terms of mechanical properties and durability, resulting in even higher performance than ordinary concrete. This review provides a comprehensive analysis of current state-of-the-art and implementations on geopolymer concrete materials, investigating how the key process factors (such as raw materials, synthesis regime, alkali concentration, water dosage, and reinforcement fillers) affect the rheological, microstructural, durability, and mechanical properties. Finally, the paper elucidates some noteworthy aspects for future research development: innovative geopolymer-based formulations (including alkali-activated blends for additive manufacturing and thermo-acoustic insulating cellular compounds), concrete applications successfully scaled in the civil-architectural fields, and the perspective directions of geopolymer technology in terms of commercialization and large-scale diffusion. Full article

(This article belongs to the Special Issue From Waste to Advance Composite Materials)

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33 pages, 3337 KiB

Open AccessEditor’s ChoiceReview

Composite Material Recycling Technology—State-of-the-Art and Sustainable Development for the 2020s

by Andrey E. Krauklis, Christian W. Karl, Abedin I. Gagani and Jens K. Jørgensen

J. Compos. Sci. 2021, 5(1), 28; https://doi.org/10.3390/jcs5010028 - 15 Jan 2021

Cited by 217 | Viewed by 28621

Abstract

Recently, significant events took place that added immensely to the sociotechnical pressure for developing sustainable composite recycling solutions, namely (1) a ban on composite landfilling in Germany in 2009, (2) the first major wave of composite wind turbines reaching their End-of-Life (EoL) and [...] Read more.

Recently, significant events took place that added immensely to the sociotechnical pressure for developing sustainable composite recycling solutions, namely (1) a ban on composite landfilling in Germany in 2009, (2) the first major wave of composite wind turbines reaching their End-of-Life (EoL) and being decommissioned in 2019–2020, (3) the acceleration of aircraft decommissioning due to the COVID-19 pandemic, and (4) the increase of composites in mass production cars, thanks to the development of high volume technologies based on thermoplastic composites. Such sociotechnical pressure will only grow in the upcoming decade of 2020s as other countries are to follow Germany by limiting and banning landfill options, and by the ever-growing number of expired composites EoL waste. The recycling of fiber reinforced composite materials will therefore play an important role in the future, in particular for the wind energy, but also for aerospace, automotive, construction and marine sectors to reduce environmental impacts and to meet the demand. The scope of this manuscript is a clear and condensed yet full state-of-the-art overview of the available recycling technologies for fiber reinforced composites of both low and high Technology Readiness Levels (TRL). TRL is a framework that has been used in many variations across industries to provide a measurement of technology maturity from idea generation (basic principles) to commercialization. In other words, this work should be treated as a technology review providing guidelines for the sustainable development of the industry that will benefit the society. The authors propose that one of the key aspects for the development of sustainable recycling technology is to identify the optimal recycling methods for different types of fiber reinforced composites. Why is that the case can be answered with a simple price comparison of E-glass fibers (~2 $/kg) versus a typical carbon fiber on the market (~20 $/kg)—which of the two is more valuable to recover? However, the answer is more complicated than that—the glass fiber constitutes about 90% of the modern reinforcement market, and it is clear that different technologies are needed. Therefore, this work aims to provide clear guidelines for economically and environmentally sustainable End-of-Life (EoL) solutions and development of the fiber reinforced composite material recycling. Full article

(This article belongs to the Special Issue From Waste to Advance Composite Materials)

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