scholarly journals Environmentally Sustainable Cement Composites Based on End-of-Life Tyre Rubber and Recycled Waste Porous Glass

Materials ◽  
2019 ◽  
Vol 12 (20) ◽  
pp. 3289 ◽  
Author(s):  
Andrea Petrella ◽  
Rosa Di Mundo ◽  
Sabino De Gisi ◽  
Francesco Todaro ◽  
Claudia Labianca ◽  
...  

In this paper, environmentally sustainable cement mortars were prepared with end-of-life tyre rubber (TR) and recycled waste porous glass (PG) as aggregates in order to obtain lightweight products characterized by renewable and not-pretreated materials specifically for indoor applications. The secondary raw materials were added as partial and/or total replacement of the conventional sand aggregate. The resulting lightweight specimens were characterized by rheological, mechanical, thermal, microstructural and wettability tests. Fine tyre rubber aggregates affected the cohesiveness of the composites, as opposite to coarse tyre rubber and porous glass. The flexural and the compressive strengths of the porous glass samples were higher than the tyre rubber samples because of the higher stiffness and good adhesion of the glass to the cement paste as observed by microstructural observations. On the contrary, an unfavorable adhesion of the tyre aggregates to the cement paste was observed, together with discrete cracks after failure without separation of the two parts of the specimens. The latter result can explain the best results obtained by tyre rubber mortars in the case of impact compression tests where the super-elastic properties of the elastomeric material were evidenced by a deep groove before complete failure. Moreover, the thermal conductivity decrease of the lightweight porous TR and PG composites was in the range of ~80–90% with respect to the sand-based samples, which suggests that they can be used as plasters and masonries, and, in the case of tyre rubber specimens, outside applications are not excluded as observed from the wettability tests.

Materials ◽  
2021 ◽  
Vol 14 (1) ◽  
pp. 225
Author(s):  
Andrea Petrella ◽  
Michele Notarnicola

Lightweight cement mortars containing end-of-life tire rubber (TR) as aggregate were prepared and characterized by rheological, thermal, mechanical, microstructural, and wetting tests. The mixtures were obtained after total replacement of the conventional sand aggregate with untreated TR with different grain sizes (0–2 mm and 2–4 mm) and distributions (25%, 32%, and 40% by weight). The mortars showed lower thermal conductivities (≈90%) with respect to the sand reference due to the differences in the conductivities of the two phases associated with the low density of the aggregates and, to a minor extent, to the lack of adhesion of tire to the cement paste (evidenced by microstructural detection). In this respect, a decrease of the thermal conductivities was observed with the increase of the TR weight percentage together with a decrease of fluidity of the fresh mixture and a decrease of the mechanical strengths. The addition of expanded perlite (P, 0–1 mm grain size) to the mixture allowed us to obtain mortars with an improvement of the mechanical strengths and negligible modification of the thermal properties. Moreover, in this case, a decrease of the thermal conductivities was observed with the increase of the P/TR dosage together with a decrease of fluidity and of the mechanical strengths. TR mortars showed discrete cracks after failure without separation of the two parts of the specimens, and similar results were observed in the case of the perlite/TR samples thanks to the rubber particles bridging the crack faces. The super-elastic properties of the specimens were also observed in the impact compression tests in which the best performances of the tire and P/TR composites were evidenced by a deep groove before complete failure. Moreover, these mortars showed very low water penetration through the surface and also through the bulk of the samples thanks to the hydrophobic nature of the end-of-life aggregate, which makes these environmentally sustainable materials suitable for indoor and outdoor elements.


2018 ◽  
Vol 27 (4) ◽  
pp. 096369351802700 ◽  
Author(s):  
Mehmet Önal ◽  
Gökdeniz Neşer

Glass reinforced polyester (GRP), as a thermoset polymer composites, dominates boat building industry with its several advantages such as high strength/weight ratio, cohesiveness, good resistance to environment. However, proper recovering and recycling of GRP boats is became a current environmental requirement that should be met by the related industry. In this study, to propose in a cost effective and environmentally friendly way, Life Cycle Assessment (LCA) has been carried out for six scenarios include two moulding methods (namely Hand Lay-up Method, HLM and Vacuum Infusion Method, VIM) and three End-of-Life (EoL) alternatives(namely Extruding, Incineration and Landfill) for a recreational boat's GRP hulls. A case study from raw materials purchasing phase to disposal/recycling stages has been established taking 11 m length GRP boat hull as the functional unit. Analysis show that in the production phase, the impacts are mainly due to the use of energy (electricity), transport and raw material manufacture. Largest differences between the methods considered (HLM and VIM) can be observed in the factors of marine aquatic ecotoxicity and eutrophication while the closest ones are abiotic depletion, ozon layer depletion and photochemical oxidation. The environmental impact of VIM is much higher than HLM due to its higher energy consumption while vacuum infusion method has lower risk than hand lay-up method in terms of occupational health by using less raw material (resin) in a closed mold. In the comparison of the three EoL techniques, the mechanical way of recycling (granule extruding) shows better environmental impacts except terrestrial ecotoxicity, photochemical oxidation and acidification. Among the EoL alternatives, landfill has the highest environmental impacts except ‘global warming potential’ and ‘human toxicity’ which are the highest in extrusion. The main cause of the impacts of landfill is the transportation needs between the EoL boats and the licenced landfill site. Although it has the higher impact on human toxicity, incineration is the second cleaner alternative of EoL techniques considered in this study. In fact that the similar trend has been observed both in production and EoL phases of the boat. It is obvious that using much more renewable energy mix and greener transportation alternative can reduce the overall impact of the all phases considerably.


Energies ◽  
2021 ◽  
Vol 14 (10) ◽  
pp. 2742
Author(s):  
Raquel Iglesias ◽  
Raúl Muñoz ◽  
María Polanco ◽  
Israel Díaz ◽  
Ana Susmozas ◽  
...  

The present work reviews the role of biogas as advanced biofuel in the renewable energy system, summarizing the main raw materials used for biogas production and the most common technologies for biogas upgrading and delving into emerging biological methanation processes. In addition, it provides a description of current European legislative framework and the potential biomethane business models as well as the main biogas production issues to be addressed to fully deploy these upgrading technologies. Biomethane could be competitive due to negative or zero waste feedstock prices, and competitive to fossil fuels in the transport sector and power generation if upgrading technologies become cheaper and environmentally sustainable.


Detritus ◽  
2021 ◽  
pp. 25-31
Author(s):  
Cecilia Matasci ◽  
Marcel Gauch ◽  
Heinz Boeni

Environmental threats are triggered by the overconsumption of raw materials. It is therefore necessary to move towards a society that both reduces extraction and keeps the majority of the extracted raw materials in the socio-economic system. Circular economy is a key strategy to reach these goals. To implement it effectively, it is necessary to understand and monitor material flows and to define hotspots, i.e. materials that need to be tackled with the highest priority. This paper is aimed at determining how to increase circularity in the Swiss economy by means of a Material Flow Analysis coupled with a simplified Life Cycle Assessment. After having characterized material flows, we analyzed two types of hotspots: i) Raw materials consumed and/or disposed at high level, and ii) Raw materials whose extraction and production generates high environmental impacts. The Material Flow Analysis shows that each year 119 Mt of raw materials enter the Swiss economy. Therefrom, 15 Mt are derived from recycled waste inside the country; 67 Mt leave the system yearly; 27 Mt towards disposal. Out of the disposed materials, 56% are recycled and re-enter the socio-economic system as secondary materials. Looking at hotspots; concrete, asphalt, gravel and sand are among materials that are consumed and disposed at high level. Yet, looking at greenhouse gas emissions generated during extraction and production, metals - including the ones in electrical and electronic equipment - as well as textiles are among the categories that carry the biggest burden on the environment per unit of material.


2020 ◽  
Vol 12 (23) ◽  
pp. 9861
Author(s):  
Jorge Martínez Leal ◽  
Stéphane Pompidou ◽  
Carole Charbuillet ◽  
Nicolas Perry

In the context of a circular economy, one can observe that (i) recycling chains are not adapted enough to the end-of-life products they have to process and that (ii) products are not sufficiently well designed either to integrate at best their target recycling chain. Therefore, a synergy between product designers and recycling-chains stakeholders is lacking, mainly due to their weak communication and the time-lag between the product design phase and its end-of-life treatment. Many Design for Recycling approaches coexist in the literature. However, to fully develop a circular economy, Design from Recycling also has to be taken into account. Thus Re-Cycling, a complete circular design approach, is proposed. First, a design for recycling methodology linking recyclability assessment to product design guidelines is proposed. Then, a design from recycling methodology is developed to assess the convenience of using secondary raw materials in the design phase. The recyclability of a smartphone and the convenience of using recycled materials in a new cycle are both analyzed to demonstrate our proposal. The Fairphone 2® and its treatment by the WEEE French takeback scheme are used as a case study.


2018 ◽  
Vol 49 (5-6) ◽  
pp. 14-17
Author(s):  
Jessica Wade ◽  
Sebastian Wood

The combined challenges of growing populations, climate change and increasing scarcity of raw materials is driving innovation in materials and design. The motivation to innovate comes from the economic impact of not doing so, as well as consumer demand, with mature customers actively seeking out more environmentally sustainable solutions.


2019 ◽  
Vol 12 (1) ◽  
pp. 147 ◽  
Author(s):  
Fernando Enzo Kenta Sato ◽  
Toshihiko Nakata

This study aims to propose a model to forecast the volume of critical materials that can be recovered from lithium-ion batteries (LiB) through the recycling of end of life electric vehicles (EV). To achieve an environmentally sustainable society, the wide-scale adoption of EV seems to be necessary. Here, the dependency of the vehicle on its batteries has an essential role. The efficient recycling of LiB to minimize its raw material supply risk but also the economic impact of its production process is going to be essential. Initially, this study forecasted the vehicle fleet, sales, and end of life vehicles based on system dynamics modeling considering data of scrapping rates of vehicles by year of life. Then, the volumes of the critical materials supplied for LiB production and recovered from recycling were identified, considering variations in the size/type of batteries. Finally, current limitations to achieve closed-loop production in Japan were identified. The results indicate that the amount of scrapped electric vehicle batteries (EVB) will increase by 55 times from 2018 to 2050, and that 34% of lithium (Li), 50% of cobalt (Co), 28% of nickel (Ni), and 52% of manganese (Mn) required for the production of new LiB could be supplied by recovered EVB in 2035.


2018 ◽  
Vol 276 ◽  
pp. 248-253
Author(s):  
Jiří Zach ◽  
Jitka Peterková ◽  
Vítězslav Novák

The paper deals with the possibilities of using secondary raw materials in the development of new advanced lightweight plasters. It was about fibers from recycled waste materials (waste paper, PET bottles, tyres) and recycled insulation (stone wool). The aim of adding fibers to these lightweight building materials was improvement of mechanical properties, improvement thermal insulation properties and reduction of crack sensitivity. It can be stated, based on the evaluation of the selected measurements, that both types of cellulose fibers and fibers from recycled tyres had positive influence on the mechanical properties, namely in the case of compressive strength. From the point of view of thermal insulating properties, it can be said that only 2 types of fibers have reduced the value of the thermal conductivity. They were mixtures with stone fibers and with recycled tyres fibers. Both of these mixtures also showed the lowest average values of bulk density. Based on the carried out research works can be it concluded that the use of recycled tyres fibers show as optimal.


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