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Waste segregation is an essential aspect of a smoothly functioning waste management system. Usually, various recyclable waste types are disposed of together at the source, and this brings in the necessity to segregate them into their categories. Dry waste needs to be separated into its own categories to ensure that the proper procedures are implemented to treat and process it, which leads to an overall increased recycling rate and reduced landfill impact. Paper, plastics, metals, and glass are just a few examples of the many dry waste materials that can be recycled or recovered to create new goods or energy. Over the past years, much research has been conducted to devise effective and productive ways to achieve proper segregation for the waste that is being produced at an ever-increasing rate. This article introduces a multi-class garbage segregation system employing the YOLOv5 object detection model. Our final prototype demonstrates the capability of classifying dry waste categories and segregating them into their respective bins using a 3D-printed robotic arm. Within our controlled test environment, the system correctly segregated waste classes, mainly paper, plastic, metal, and glass, eight out of 10 times successfully. By integrating the principles of artificial intelligence and robotics, our approach simplifies and optimizes the traditional waste segregation process. [ABSTRACT FROM AUTHOR]

Glass waste products represent a significant environmental concern, with an estimated 1.4 billion tons being landfilled globally and 200 million tons annually. This results in a significant use of land resources. Therefore, it would be highly advantageous to develop a new method for disposing of waste glass. Waste glass can be recycled and ground into waste glass powder (WGP) for use in solidified soil applications as a sustainable resource. This study is based on solidified soil research, wherein NaOH, Ca(OH)2, and Na2SO4 were incorporated as activators to enhance the reactivity of WGP. The optimal solidified soil group was determined based on unconfined compressive strength tests, which involved varying the activator concentrations and WGP content in combination with cement. X-ray diffraction (XRD) was used to study the composition of solidified soil samples. Microscopic pore characteristics were investigated using scanning electron microscopy (SEM), and the Image J software was employed to quantify the number and size of pores. Fourier-transform infrared spectroscopy (FTIR) was employed to examine the activation effect of waste glass powder. This study investigated the solidification mechanism and porosity changes. The results demonstrate that the addition of activated WGP to solidified soil enhances its strength, with a notable 12% increase in strength achieved using a 6% Ca(OH)2 solution. The use of 2% concentration of Na2SO4 and NaOH also shows an increase in strength of 7.6% and 8.6%, respectively, compared to the sample without WGP. The XRD and SEM analyses indicate that activated WGP enhances the content of hydrates, reduces porosity, and fosters the formation of a more densely packed solidified soil structure. [ABSTRACT FROM AUTHOR]

In 2022, 150 million tons of glass was produced globally, and approximately 47% of that amount was glass hollowware for tableware and food, beverage, and cosmetics packaging. Glass is considered one of the most recyclable materials as its properties and performance do not degrade upon reheating and reforming; yet only 21% of global production is recycled. The most recycled type of glass is soda–lime silicate bottle glass based on its widespread availability and its ability to accommodate higher levels of contamination compared to flat glass and specialty glass. Bottle glass manufacturers melt glass batch that is 10%–60% recycled glass cullet, limited only by the availability of pristine glass cullet that is free of contaminants such as plastic, metal, and organic material. Increasing rates of recycled content in glass manufacturing is stymied by the lack of a supply chain to deliver high quality glass cullet to manufacturers, as well as risk of material incompatibility and contamination. In this work, post‐consumer glass bottles of different colors, shapes, and brands were analyzed for chemical composition and thermal properties to quantify variation across five major color families: clear, blue, amber, forest green, and emerald green. This work shows that post‐consumer bottles of different colors and brands can be remelted without risk of material incompatibility and presents various processing methods to control color homogeneity in glass produced exclusively from mixed color cullet from recycled glass bottles. [ABSTRACT FROM AUTHOR]

The main objective of this research is the explanation of the replacement of feldspar limestone imported from Spain with recycled automotive glass, in order to reduce waste and promote environmental sustainability. Details and efforts of making porcelain ceramics from local raw materials such as quartz, kaolin and glass are also given. Replacing the feldspar with reclaimed automotive glass shows the effect of the Na2O and CaO solvents contained in the glass on the sintering and crystallization of the studied porcelain. The results showed that the added glass contributes to the reduction of the density and the acceleration of the sintering process, by occupying the sites of the open spaces, observed in the samples not containing feldspars. By reaching a nonporous ratio at a temperature of 1000∘C, the melting of the material is accelerated due to the dissolved oxides it contains, in addition to the linear shrinkage rate in samples that contain a lot of glass reaching the normal level of porcelain (about 12%) at low temperature compared to ordinary porcelain. [ABSTRACT FROM AUTHOR]

The work was devoted to the study of the recycling of household glass waste by the electric pulse method. Cullet and glass containers were considered as the object of research. Cullet and used glass containers are considered suitable for recycling among solid household waste. The treatment of solid household waste was carried out with the formation of electrical discharges in an inhomogeneous environment (glass fragments and glass products in an aqueous environment). The experiments were carried out at different values of pulse discharge voltage (from 12 kV to 37 kV), capacitor bank capacity (from 0.4 to 1.2 µF), number of pulse discharges (from 250 to 1,000) and frequency (from 0.3 Hz to 2 Hz). The dependence of the output of the finished product on the parameters of electric pulse discharges has been revealed from the research results. According to the main results of the research work, it was found that as the parameters of electric pulse discharges increase, the yield of the finished product increases. The data made it possible to assign effective parameters for processing cullet and glass products using the electric pulse method. The granulometric composition of the powder material obtained by this method has been determined. A product with a diameter of the largest fraction of 5-8 mm and a diameter of a small fraction of 0.4 mm and 0.7 mm was obtained. The results of the experiment can be used in research on saving natural resources, energy conservation and solving environmental problems of solid waste recycling. Powdered glass is used as a thermal insulator and decorative material in construction. In addition, crushed glass is used in the production of concrete as an additional raw material. [ABSTRACT FROM AUTHOR]

This study aims to address the complex stress state commonly observed in concrete structures in practical engineering, as well as the challenges posed by resource scarcity and environmental pollution. To achieve this, a total of 168 cylinder specimens of glass fiber recycled coarse aggregate concrete (GFRAC) were designed for conventional triaxial compression tests. The analysis of the test results reveals that the application of lateral restraint force induces a shift in the failure mode of GFRAC from longitudinal splitting failure to plastic deformation failure, occurring either in the middle or at the end of the specimen. The lateral constraint force can effectively improve the stress and strain at the peak point of GFRAC and the modulus of elasticity of the specimen. The glass fiber increases the peak stress of the specimen, and the maximum growth rate is 20%. On the contrary, the glass fiber reduces the peak strain, and the maximum reduction is 49.66%. Increasing the replacement rate of recycled coarse aggregate will lead to a decrease in peak stress, with a maximum decrease of 19.17%. Glass fiber (GF) limits the appearance and propagation of cracks by bridging, pulling out or breaking. Finally, three different failure criteria are used to analyze the triaxial compression state of GFRAC from a macro perspective. [ABSTRACT FROM AUTHOR]

Siemens is leading a £54 million R&D project to develop an optimized approach for boosting glass furnaces with electrical heating, which is estimated to cut UK emissions from glass manufacturing by 56%. The Glass Futures experimental facility in St Helens, Merseyside, will be the first to adopt Siemens' new digital control system, PCS Neo, to manage all plant operations and provide end-to-end monitoring and control. The facility aims to model and develop a solution that large-scale manufacturers can adopt or learn from to achieve significant emission reductions in glass manufacturing. The text also discusses various updates and developments in the glass industry, including new products, partnerships, and sustainability initiatives. [Extracted from the article]

Composite structures with L, C, and T shape geometries are commonly used in the design of aerospace structural components. These complex structures are prone to delamination failure at the curved region. This study investigates the effect of thickness and recycled milled glass fiber fillers to improve the strength properties and delamination resistance of glass/epoxy composite angle brackets. Different thicknesses of 3.5 mm (16 layers), 5 mm (24 layers), and 6.5 mm (32 layers) specimens were subjected to four-point bending test with acoustic emission (AE) monitoring for evaluating damage resistance. Mechanical results reveal that the specimen with a higher thickness of 6.5 mm has better damage tolerance, followed by 3.5 and 5 mm angle brackets. Moreover, the location of AE signals and % of AE hits noticed the initiation and propagation of delamination in 5 mm thickness specimen at the earlier stage of loading. However, the curved beam strength and interlaminar tensile strength (ILTS) of 5 mm thickness specimen were improved by 31.02% and 19.2% respectively, through the incorporation of 2 wt% of fillers. Further, the interfacial adhesion between the fillers and epoxy matrix was studied using Fourier-transform infrared analysis to confirm the improvement of delamination resistance in 5 mm thickness specimen. Finally, the mechanical and AE results were well correlated with field emission scanning electron microscope images to characterize the damage mechanisms in composite angle brackets. Highlights • Effect of thickness on the delamination resistance of composites was studied. • Interlaminar properties of composite angle brackets were assessed. • Acoustic emission parameters were used to study the damage mechanisms. • Recycled milled glass fillers were employed to improve delamination resistance. • Mechanical and acoustic emission results were correlated with field emission scanning electron microscope images. [ABSTRACT FROM AUTHOR]

[Display omitted] • Sensitivity analysis in packaging EoL modeling to evaluate influence in EoL impacts. • Take-back presents environmental benefits due to paper and glass recycling. • Incineration with energy recovery reduces EoL impacts from pharmaceutical packaging. • Smaller pharmaceutical packaging and EoL valorization reduces impacts. • Decisions at packaging early design stage influence EoL impacts. Pharmaceutical packaging waste has increased due to a higher global demand for pharmaceutical products, leading to more waste generation and associated environmental impacts. The main goal of this article is to present a cradle-to-grave life cycle assessment of pharmaceutical packaging, evaluating end-of-life (EoL) alternatives, aiming to identify hotspots and opportunities for improvement. A life cycle model was implemented for three types of pharmaceutical packaging (blisters, sachets, bottles; 23 packaging). The functional unit is the storage and delivery of medicines containing the same active pharmaceutical ingredient, dosage, and amount of medicines. Two EoL analyses were performed: 1) compare take-back (recycling and incineration) with domestic waste collection (landfill or incineration); and 2) assess different EoL situations of pharmaceutical packaging in Europe. A life cycle impact assessment was performed for 13 categories. Analysis 1 shows that take-back presents lower environmental impacts than domestic waste collection for seven out of 13 categories due to paper and glass recycling benefits. Analysis 2 shows that in the take-back, higher amounts of packaging are recycled or incinerated, which leads to lower EoL impacts. A sensitivity analysis was performed to evaluate the influence of parameters and assumptions in packaging EoL impacts. Packaging production contributes significantly to life cycle impacts, followed by transportation, EoL, and packing process. Ecodesign initiatives are recommended, such as packaging with less material and volume, using materials with lower impacts to significantly reduce the impacts of pharmaceutical packaging. [ABSTRACT FROM AUTHOR]

The climate is changing rapidly due to anthropogenic greenhouse gases. Glass is a significant contributor to these emissions, with 95 million tons of CO2 being emitted due to glass manufacturing in recent years. Furthermore, glass recycling remains poor in the United States, and most glass is left to landfill after a single use. The lack of recycling and the carbon footprint of manufacturing have made glass an environmentally damaging material despite its theoretical infinite recyclability. Additionally, glass has the potential to enable next‐generation energy materials, enabling the necessary technology for a green economy. In this review, we briefly cover the challenges of glass manufacturing and how to make glass the benchmark material for a carbon‐neutral economy. [ABSTRACT FROM AUTHOR]

This study investigates the bond behavior of glass aggregate–reinforced concrete (GARC) after freeze–thaw cycles, considering a number of freeze–thaw cycles (10, 20, and 30) and fine aggregate replacement rates (25%, 50%, and 75%) as variable parameters. Sixteen groups of specimens were designed to conduct central pullout tests after freeze–thaw cycles, and the bond–slip curves of each group were plotted. The bond performance of the GARC and its failure mechanism after freeze–thaw cycles were examined by analyzing the failure mode, ultimate bond strength, peak displacement, and bond stiffness. The results indicated that freeze–thaw cycles had a deteriorating effect on the bond performance of GARC. However, under the effect of the same number of freeze–thaw cycles, in comparison with the bonding performance of natural aggregate–reinforced concrete, GARC exhibited a higher resistance to the deterioration effect of freeze–thaw cycles, which was enhanced by increasing the replacement rate. In addition, the optimization effect of glass sand on the bonding properties became increasingly prominent as the freeze–thaw cycle deepened. Therefore, after freeze–thaw cycles, GARC exhibited excellent bonding behavior, and 75% GARC exhibited the best bonding performance. Based on the experimental data, considering the number of freeze–thaw cycles and aggregate replacement rate, the bond–slip constitutive equation of GARC after freeze–thaw conditions was established. Glass aggregate–reinforced concrete has excellent resistance to freeze–thaw cycle damage. After freeze–thaw cycles, glass aggregate concrete has better bonding performance with reinforcement than natural aggregate concrete, and the degree of improvement is related to the replacement rate of glass sand. The bond mechanism between the glass aggregate concrete and reinforcement was explained after freeze–thaw cycles. The research results proved the potential capacity and advantages of glass aggregate concrete under a complex environment and demonstrated the research potential of glass aggregate concrete. In addition, this study provided a new approach to improving the resistance of conventional concrete materials to complex environments. By replacing part of the river sand in concrete with glass sand, the resistance of concrete to freeze–thaw cyclic damage could be significantly improved without affecting the mechanical properties of reinforced concrete. This could also effectively address the problem of recycling waste glass and increasing shortage of river sand. [ABSTRACT FROM AUTHOR]

Glass fiber-reinforced plastics (GFRP) have been produced in large quantities for over half a century and nowadays their waste has become a problem worldwide. Their recycling is difficult because they are predominantly manufactured from thermosetting matrices that are not suitable for secondary processing. Only few technologies are able to target full-scale utilization of residual mechanical performance at recycling, with the replacement of gravel in asphalt concrete being one of them. The possibility of introducing crushed GFRP (GFRP crumb) into asphalt concrete and its impact on mechanical characteristics have been investigated in our study. As the source of GFRP, road noise-protection fence was chosen due to large quantities of its waste accumulated in urban economy. Several approaches to produce crumbs were attempted with only shredding being successful. The GFRP crumb has provided excellent mechanical performance of asphalt concrete fabricated by standard routine. In particular, the improvement in compressive modulus was 40%, even under conditions of elevated asphalt concrete temperature at 50 °C. Besides, introduction of GFRP crumb reduced the overall weight of asphalt concrete mixture, providing further reduction of a carbon footprint. The results obtained indicated that recycling of GFRP waste as replacement of gravel in asphalt concrete provides an economically and environmentally safe solution. [ABSTRACT FROM AUTHOR]

Theoretically, glass can be recycled entirely, but there are several requirements for remanufacturing. For the first time, this work studied industrial bottle waste glass (WG), which cannot be used to remanufacture new glass as a cement replacement for concrete applications. Wet and dry milling treatments were performed to reduce the particle size of WG and remove fibre and plastic contaminants. The different waste glasses treated were characterised by chemical, physical, and morphological analysis. Afterwards, mortar-level studies followed, using raw WG and wet-milled WG (AGWG) as a 10% Portland cement replacement. Mechanical and several durability indicators were assessed. WG and AGWG incorporation improved mortar performance against water capillary absorption, chloride ingress, and alkali–silica reaction. The unfavourable effect, namely, mechanical strength loss on glass-modified mortars, was mainly due to fibre contaminants observed by SEM on WG and AGWG samples. Even though wet milling reduced the amount and length of the fibre contaminants, it still did not guarantee adequate mechanical strength for the mortar. Thus, additional or alternative treatments, such as thermal treatments, must be explored. [ABSTRACT FROM AUTHOR]

The production of Portland cement (PC) is associated with carbon emissions. One-part geopolymer "just add water" is a user- and environmentally-friendly binder that can potentially substitute PC. However, there is limited research on the setting time, fresh, and strength properties of one-part metakaolin (MK)-based geopolymer concrete (OMGPC) incorporating recycled aggregates. Hence, the study explored the fresh, mechanical (compressive, flexural, splitting tensile, and E-modulus) and microstructural properties of ambient cured (7-, 28-, and 90-day) OMGPC containing recycled waste plastics (RESIN8) and recycled fine waste glass aggregate (FWG) at 5% and 10% by volume of the sand. The study result shows that 2% trisodium phosphate by wt. of the binder retard the initial and final setting times of OMGPC. At the same time, the incorporation of RESIN8 and FWG aggregates improved the workability of geopolymer concrete. The lightweight properties of RESIN8 aggregate reduce the hardened density of OMGPC, while the FWG specimens show a similar density to the control. The compressive strength of RESIN8 and FWG OMGPC range from 19.8 to 24.6 MPa and 26.9 to 30 MPa, respectively, compared to the control (26 to 28.9 MPa) at all curing ages. The flexural and splitting tensile strength of the OMGPC range from 2.2 to 4.5 MPa and 1.7 to 2.8 MPa, respectively. OMGPC is a viable alternative to Portland cement, and FWG can substitute sand in structural concrete by up to 10% and RESIN8 aggregate at 5% by volume of the natural sand. [ABSTRACT FROM AUTHOR]

Abrasive waterjet (AWJ) machining offers the possibility of creating a wide range of features on mechanical parts with different degrees of complexity with a relatively high efficiency. However, after the roughing passes, the surface quality of features such as blind pockets is rather low, with unfavorable implications for surface waviness and form deviations apart from high surface roughness. Apart from the traditional methods for finishing, such as grinding or lapping, it is worth attempting either to improve the surface quality obtained during roughing by an AWJ or to integrate a post-processing step by using a pure WJ in the existing process in order to ameliorate the surface quality. Thus, in the current study, the effect of pure waterjet (WJ) post-processing of machined pockets by AWJ milling on a Ti-6Al-4V workpiece using recycled glass beads was investigated under different conditions. The findings indicate that although the different post-processing treatments by a pure WJ can affect the surface quality on average, these differences are not considerably important, probably due to an insufficient capability of material removal, which hinders the smoothing effect on machined surfaces. Thus, it was indicated that a higher number of post-processing passes under different conditions than those of the roughing pass can be more favorable for efficient post-treatment by a pure WJ. [ABSTRACT FROM AUTHOR]

Thermoset polymer composite was made in an original version less expensive than the known techniques, in which alumina-borosilicate glass recycled from used laboratory glass was chosen as filler into the mixture of starting materials together with polyurethane resin as a matrix. The matrix/filler weight ratio was modified during the experiment from 0.67 to 1.22 and this change influenced the features of manufactured products. The temperature and time of the thermoset polymer curing process played an important role. It was opted for the electric heating of the material mixture up to 300-305 ℃ with the heating rate between 3.06- 3.22 ℃/min, keeping at the maximum temperature for 100 min, and cooling in about 30 min. Results showed making a dense material type with relatively low heat conductivity. Tensile strength was around 40 MPa and compressive modulus of elasticity registered around 19 GPa, above the level of thermoplastic polymer. [ABSTRACT FROM AUTHOR]

Photovoltaic (PV) solar panels suffer from efficiency losses due to the accumulation of dust on their surface during operation, as well as the loss of transparency in the top glass. The efficiency can be increased when hydrophobic films are deposited on the top glass of the solar cells. The top glass of solar cells must have three characteristics: high transmittance in the 380–750 nm range, a band gap greater than 3.2 eV and a refractive index higher than 1.23. So, the films require the same characteristics. This work presents an increase in the contact angle (related to an increase in the hydrophobic character) when Ta2O5 is partially substituted with ZnO. The studied films, physically deposited on glass by e-gun technology, present a non-crystalline state in the form of the X-ray patterns shown. The films have a transmission of 75%–80% in the visible range. The morphology and roughness of the coatings were evaluated by atomic force microscopy. All films show the values of the Millipore water contact angle higher than 91 degrees, leading to the acquisition of hydrophobic properties on the surface. In comparison, the substrate is hydrophilic, with an average contact angle of 53.81 ± 2.16. The hydrophobic properties and self-cleaning ability make the films recommendable for application. The band gap of the coatings was calculated with the Tauc method, and they have values of 4.5–4.6 eV. [ABSTRACT FROM AUTHOR]

• Produced added-value glass-ceramics without using chemical additives. • Predicted the crystallisation behaviour of the glass-ceramics. • Anorthite was formed and transformed into wollastonite in glass-ceramics. • The incorporation of waste glass densified and refined the pore structure. Disposal of waste glass and incinerated sewage sludge ash (ISSA) in landfills is a waste of resources and poses significant environmental risks. This work aims to recycle waste glass and ISSA together to form value-added glass-ceramics. The physical and mechanical properties, leaching behaviour, and microstructure of the glass-ceramics produced with different proportions of waste glass powder (WGP) and ISSA were investigated. Thermodynamic calculations were performed to predict the formation of crystalline phases and the phase transformation involved. The results showed the potential of WGP and ISSA as raw materials in glass-ceramics production. WGP effectively densified the microstructure of the glass-ceramics by forming a viscous phase. As WGP content increased, the total porosity of glass-ceramics decreased whereas the density increased, accompanied by the formed anorthite transforming into wollastonite. The incorporation of WGP densified and refined the pore structure of the glass-ceramics, thereby improving the mechanical properties and reducing the water absorption. The glass-ceramics produced with a 50:50 blend of WGP and ISSA exhibited the highest compressive strength of 43.7 MPa and the lowest water absorption of 0.3 %. All fabricated glass-ceramics exhibited innocuous heavy metal leaching. The co-sintering of ISSA and WGP can produce additive-free glass-ceramics, characterized by reduced energy consumption and notable heavy metal immobilization capacity. These materials hold promise for utilization in construction as building materials. [ABSTRACT FROM AUTHOR]

Cementitious–glass composite bricks (CGCBs) with 3D-printed reinforcement structures made of PET-G could be an innovative production method that relies on recycling glass waste (78%) and PET-G (8%). These bricks offer a promising solution for the construction industry, which has a significant impact on climate change due to its greenhouse gas emissions and extensive use of natural aggregates. The approach presented in this article serves as an alternative to using conventional building materials that are not only costlier but also less environmentally friendly. The conducted research included mechanical tests using digital image correlation (DIC), utilized for measuring deformations in specimens subjected to three-point bending and compression tests, as well as thermal investigations covering measurements of their thermal conductivity, thermal diffusivity, and specific heat. The results highlighted the superior thermal properties of the CGCBs with PET-G reinforcements compared to traditional cementitious–glass mortar (CGM). The CGCBs exhibited a 12% lower thermal conductivity and a 17% lower specific heat. Additionally, the use of specially designed reinforcement substantially enhanced the mechanical properties of the bricks. There was a remarkable 72% increase in flexural strength in the vertical direction and a 32% increase in the horizontal direction. [ABSTRACT FROM AUTHOR]

Ultra-high-performance concrete (UHPC) is a high-tech concrete whose excellent mechanical and durability characteristics are ascribed to the homogeneity and high packing density of its matrix. However, due to the high contents of cement and silica fume usually necessaries for achieving this packing density, UHPC's final cost and carbon-footprint are far higher than standard concretes. Therefore, over the last few years, the spotlight of UHPC's research has focused sharply on the analysis of locally available supplementary cementitious materials as partial replacement of cement and silica fume. This article presents an investigation to analyze the effect of rice husk ash (RHA) as partial substitution of cement in a previously optimized mixture of recycled-glass-UHPC by means of several statistical tools. Cementitious materials employed in this research involved silica fume, limestone powder, recycled glass powder and ordinary Portland cement (OPC). Based on the results, it can be concluded that RHA addition in the optimized glass UPHC yields to a significant decrease in the workability of concrete and a slight decrease of compressive strength. Results also demonstrated the high interaction between the RHA and water contents, which could be ascribed to the water absorption and internal curing provided by RHA particles. [ABSTRACT FROM AUTHOR]

The given text provides a range of information related to the glass industry. It discusses topics such as the future of creative glass in Sunderland, efforts to reduce carbon emissions in glass production, advancements in glass cutting technology, and the use of renewable energy in glass manufacturing. It also highlights collaborations and partnerships aimed at creating sustainable packaging options for beauty brands. Additionally, the text includes statements and announcements regarding low carbon hydrogen production, low carbon glass alternatives, solar integrated glass units, solar glass manufacturing using recycled materials, glass recycling initiatives, and a policy position document released by British Glass. [Extracted from the article]

In order to promote the sustainable use of resources and reduce the waste of waste glass and tailings resources. The present study focuses on a fluorite mine as the research subject, utilizing coarse tailings, fine tailings, cement substitute-curing agent, and recycled waste glass as the primary raw materials. It investigates the changes in compressive strength of coarse tailing with varying sand- binder ratios and glass content at 3-day, 7-day, and 28-day intervals when the filling slurry concentration is set at 77% and the ratio of coarse tailings to fine tailings is maintained at 2:1. The findings indicate that there is minimal impact on the compressive strength of test blocks when using a sand binder ratio of 4:1 and a glass sand content below 10%. However, once the glass sand content exceeds 10%, a significant decline in compressive strength occurs. Scanning electron microscope (SEM) images reveal ettringite crystal formation in test blocks with both 0% and 25% glass sand content due to high levels of Na2O in the glass sand. This leads to internal expansion within test blocks resulting in reduced strength. Notably, when using a sand-binder ratio of 8:1 along with a glass sand content of 25%, early strength characteristics are observed for test blocks. Furthermore, incorporating glass sand has little influence on late-stage strength for backfill when employing either an 8:1 or 12:1 sand-binder ratio. Based on this experiment conducted under conditions including mass concentration of 77%, the optimal waste-glass-to-mine-tailings-filling-sand-binder-ratio is determined as 8:1with a corresponding glass content of 25%. [ABSTRACT FROM AUTHOR]

A circular economy is expected to reduce the use of primary resources through the reuse of products, components, and materials. Material recycling, though advantageous in many cases for saving primary resources by diverting them away from the landfill, may have perverse effects when analyzed from a systems perspective considering the entire material life cycle as well as economy‐wide effects of recycling. Using the case of metals, glass, and plastics recycling, the advantages of a systems view including the entire material life cycle in analyzing material recycling are illustrated. The advantages of recycling as compared to virgin production may vary significantly depending of the energy and resource requirements during the recycling process, logistics, and alloying of materials. Expanding the systems view further to analyze the economy‐wide effects of material recycling reveal the possibility of rebound effects which may reduce or even negate its advantages. Sustainable consumption is absolutely essential along with any technological advances to counter the rebound effects that may lead to overshoot. The article demonstrates the importance of considering a systems view incorporating a life cycle perspective and economy‐wide effects in analyzing and trying to maintain the advantages of material recycling. This article is categorized under:Climate and Environment > Circular EconomyEmerging Technologies > MaterialsClimate and Environment > Pollution Prevention [ABSTRACT FROM AUTHOR]

Composite materials are used in a substantial number of products. Environmental concerns highlight the need for the inclusion of recovered waste in their formulation, thus reducing their carbon footprint. These solutions raise the need to confirm the mechanical characteristics of these materials, avoiding unwanted failures. In this work, the authors present an experimental study on the drilling effects on fibrous–particulate hybrid composites made of glass/carbon fabrics and three different micro-inclusions: silica particles, recycled carbon fibre powder and cement. The mechanical features of the plates are confirmed by thrust force monitoring during drilling and by flexural testing. The range of results confirm the mechanical outcomes due to machining. The plates with monolithic carbon fabric or with carbon fabric plies in the outer plies returned higher mechanical characteristics. The plates with micro-inclusions had enhanced the flexural strength by 23% and 10%, in 40% and 60% fabric plates, respectively. The results demonstrate that the use of alternative formulations with micro-inclusions from recovered waste can contribute both to the reduction of the mechanical degradation of drilled hybrid composites and to environmental purposes by avoiding the increase in landfill waste. [ABSTRACT FROM AUTHOR]

Expansive clay soils, characterized by their propensity to undergo significant volume changes in response to moisture variations, present considerable challenges in construction engineering. These challenges manifest as structural damage, including fractures, asymmetrical settlements, and erosion. This study investigates the application of sustainable waste materials, specifically a mixture of plastic and glass waste, as an innovative approach to soil stabilization. In the context of Anbar, Iraq, laboratory experiments were conducted to evaluate the efficacy of incorporating plastic and glass waste in various proportions (0%, 4%, 5%, 6%) into clayey soil. The primary focus was to assess changes in geotechnical properties, notably the reduction in swelling potential and alterations in the maximum dry unit weight of the soil. Results indicated that the inclusion of waste materials in the specified proportions significantly mitigated the soil's swelling behavior, with reductions of 2%, 3%, and 5% observed for the respective waste content. Concurrently, enhancements in soil density were recorded, with increases in the maximum dry unit weight by 4%, 5%, and 9% corresponding to the same proportions of waste additives. These findings underscore the potential of using recycled waste materials in soil stabilization, aligning with environmental sustainability goals through the repurposing of waste. Additionally, this approach offers an economically viable alternative to traditional stabilization methods. The utilization of waste materials not only addresses the environmental impact of construction activities but also contributes to the broader goal of waste management and resource conservation. [ABSTRACT FROM AUTHOR]

The stabilisation of expansive clay subgrades using recycled glass (RG) was proposed, as a sustainable ground improvement technique. Previous studies mainly focused on using RG powder with contents up to 10%, while the current study utilised sand-size particles and up to 40% RG content. Physical properties, compressibility, strength characteristics, and long-term climatic effects on the volumetric behaviour of stabilised clay were investigated. Volumetric responses of stabilised clay were analysed through a constitutive model developed for environmentally stabilised clay. The experimental results revealed that the plasticity of mixtures decreased by 30% as RG content increased to 40%. By using larger RG particles, the strength and bearing capacity increased by about 45% and 130% with the addition of 25% RG. However, adding about 6% of glass powder was sufficient to increase the strength and bearing capacity to about 100% and 200%, respectively. The swell-shrink results suggested that the maximum swelling was achieved in the second cycle in which the clay classification was converted from medium to high expansive clay. The experimental results were also compared and discussed with corresponding data collected from the literature. The outcomes of this study advance the prediction and understanding of the mechanical behaviour of RG-stabilised clay. [ABSTRACT FROM AUTHOR]

This paper explores the mechanical recycling of continuous fiber-reinforced thermoplastics (CFRTPs) waste into injection molded products, focusing on the influence of recycling parameters on fiber length and mechanical properties. CFRTPs are gaining attention for their promising attributes, including weight-specific mechanical properties, short cycle times, storability, and recyclability, making them suitable for diverse applications. However, as CFRTP production rates rise, recycling strategies become crucial for sustainability. This study investigates the processability of CFRTP waste, defines size reduction conditions, and evaluates the impact of various compounding parameters such as temperature, screw speed, and fiber volume content during extrusion. The research findings indicate that higher screw speeds lead to fiber length reduction, whereas elevated temperatures result in longer fibers. Increased fiber volume intensifies interactions, resulting in shorter lengths. Additionally, the study examines the influence of injection molding parameters such as back pressure, screw speed, and initial fiber length on the resulting fiber length and mechanical properties of injection molded specimens, emphasizing the need for precise parameter control to optimize performance in recycled CFRTPs. Key findings are that increasing the initial fiber length from 260 μm to 455 μm results in an average fiber length after injection molding of 225 μm and 341 μm, respectively. This implies that longer initial fibers are more prone to breakage. Regarding the mechanical properties, increasing back pressure from 20 bar to 60 bar results in a reduction in Young's modulus of approximately 40 MPa. Higher screw speed also reduces modulus by approximately 70 MPa due to intensified fiber–screw interactions. However, back pressure and screw speed have neutral effects on the tensile strength and the elongation at break. [ABSTRACT FROM AUTHOR]

Adsorption is a rapid and known method to treat wastewater and remove contaminants such as ammonia (NH3+) and nitrogen derivatives. Herein, novel adsorption materials are demonstrated to eliminate the most hazard industrial and municipal contaminants including ammonia and nitrogen derivatives. Oxide glasses as new adsorbing media are beneficial for wastewater treatment due to dangling bond defects and non-bridging oxygen, which act as adsorption centers. Oxide glasses are characterized by their low cost and simple preparation method. Different types of oxide glasses including borate, phosphate, silicate, and germinate glasses are used as adsorbents to estimate the glass type of the optimal removal efficiency. It is found that the higher removal efficiency is exhibited for both borate and silicate glasses. Therefore, by preparing hybrid borate-silicate (borosilicate) glass, the best efficiency is achieved. The influences of boundary conditions including contact time, adsorption temperature, and adsorbent dosage on the efficiency of adsorption process are demonstrated. The optimal removal efficiency is achieved when using borosilicate glass sample (as adsorbent) with contact time of 90 min, adsorption temperature of 70 °C, and adsorbent dosage of 1.5 mg/100 ml. Finally, by comparing our results with the previous adsorption treatment works, it is found that adsorption capacity of ammonia reached to 9.12 mg/g, which is a valid and acceptable value. [ABSTRACT FROM AUTHOR]

In this study, a glassy borosilicate compound was synthesized using recycled glass and natural clays. Even though glass recycling is the generally accepted standard practice for managing glass waste, fine fractions of container soda-lime glass or cullet of other compositions are still disposed of in landfills. Thus, advanced upcycled products that offer greater economic motivation for implementation in industry may be the key to success, but these are frequently linked to alternative methods of product synthesis. Here, a simple and facile route of borosilicate compound production has been synthesized and characterized. The physicochemical characterization of the compounds was carried out to determine their properties and the antibacterial efficacy of the synthesized compound against Escherichia coli (E. coli) was investigated. The structural and spectroscopic characteristics were identified as a compound that conformed to quartz, cristobalite, and silicon hexaboride (SiB6). For the antibacterial activity, two test types were typically performed; in the first one, the dilutions of the grind were combined with chloramphenicol at a concentration of 20 µg/mL to perform a synergistic action against the bacteria and in the second one, only the amorphous borosilicate compound was tested against E. coli ATCC 25922 strains. The treatments applied considered the dilutions from 8 to 40 µg/mL. The minimum inhibitory concentration (MIC) sensitivity tests began with incubation at 37 °C in the tubes and subsequent seeding in Petri dishes for colony-forming unit (CFU) counting. The results obtained indicated that the samples possessed a productive antibacterial effect, which support their use in various biomedical applications. [ABSTRACT FROM AUTHOR]

In the modern age, where global warming is intensifying year by year, carbon reduction has long been an issue that countries all over the world must pay attention to. Therefore, governments have established a carbon tax and trading system to control the total carbon emissions of each country. According to the European Container Glass Federation (FEVE), every 10% recycled waste glass can reduce carbon dioxide emissions by 5%. Recycling waste glass will not only save the cost of raw materials but also make a significant contribution to sustainable development. This study uses the circular economy concept in the glass industry to recycle waste glass. It combines activity-based costing (ABC) and the Theory of Constraints (TOCs) to establish a production decision-making model, including carbon tax and trading. The objectives of this study are to solve the problem through mathematical programming to explore the impact of the carbon tax and carbon rights cost on corporate profits and to provide the government with the results as a reference for establishing a carbon tax system. [ABSTRACT FROM AUTHOR]

Marl soils with different carbonate contents usually show more unpredictable behavior than other problematic soils. In some marl soil groups, freezing–thawing (F-T) cycles can result in slaking and detrimental effects on the soil mechanical properties. However, up to now, studies on the performance of stabilized marl with alkali-activated materials under F-T cycles have been noticed to be quite limited. Moreover, the filled pores in the marl layered matrix and cementing materials bonded particles during the formation mechanism have not been clearly explored yet. This study investigated the improvement of slaking marl soil with a geopolymer based on recycled glass powder (RGP) activated with sodium hydroxide (NaOH) for complete replacement of industrial cement. The study evaluated the effects of the changes of the curing times (7, 28, and 90 days), RGP content (5%, 10%, and 15%), alkali concentration (2, 4, and 6M), curing temperatures as close to research conditions as possible (20°C and 50°C), volumetric strain, and 12 cycles of F-T for the unconfined compression strength (UCS) and consolidation test results. The control sets, comprising natural and cement-stabilized samples, were prepared and examined to provide a reference baseline. The mineralogical and microstructural characteristics were determined through X-ray diffractometer (XRD) and scanning electron microscopy (SEM) techniques. The results revealed that the cyclic F-T actions damaged the bonding between marl layers and made an irreversible structure with a lower UCS value. The results indicated that after conducting F-T cycles, the UCS of stabilized samples (15% RGP content, 2 M NaOH, 90 days curing) diminished from 3,667 to 2,668 kPa (27% reduction) after 12 F-T cycles. The one-dimensional consolidation test results confirmed a considerable reduction (92% for 90-day cured samples) in the settlement. [ABSTRACT FROM AUTHOR]

In this article, the authors investigate the effectiveness of glass and metal recycling in Roman towns. The comparison of sealed primary deposits (reflecting what was in use in Roman towns) with dumping sites shows a marked drop in glass and metal finds in the dumps. Although different replacement ratios and fragmentation indices affect the composition of the assemblages recovered in dumps, recycling appears to have played a fundamental role, very effectively reintroducing into the productive chain most glass and metal items before their final discard. After presenting a case study from Pompeii, the authors examine contexts from other sites that suggest that recycling practices were not occasional. In sum, recycling should be considered as an effective and systematic activity that shaped the economy of Roman towns. [ABSTRACT FROM AUTHOR]