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[Display omitted] • Investigating policy impact on reverse supply networks for end-of-life wind blades. • 3 policy scenarios: As-Is; upcoming EU Proposal on waste shipments; Landfilling Ban. • Optimal material flows and recycling facilities locations for each policy scenario. • Trade-off between circularity and emissions in 'EU Proposal' and 'Landfilling ban' • Landfilling fees to be significantly increased to reach circularity for wind blades. Wind energy is key to supply renewable energy. However, the increasing number of end-of-life wind turbines is still predominantly landfilled, while regulatory aspects such as waste shipment and landfilling rules hinder the development and scalable implementation of reverse supply networks. This work aims to understand how EU directives impact the structure and viability of circularity-enabling networks by investigating the optimal reverse supply network design for end-of-life wind turbine blades under different policy scenarios. Three policy scenarios were explored through a Mixed-Integer-Linear-Programming model: (i) 'as-is'; (ii) 'EU Proposal 2021/0367′, removing transboundary restrictions on waste shipments; (iii) 'Landfilling Ban' enforcing an EU-wide ban on landfilling composites. The optimal reverse supply networks with minimum costs were identified for each scenario, contextually determining location and sizing of recycling facilities and calculating landfilling quota and GHG emissions. The costs and emissions were minimum for the EU Proposal scenario, at 15,706,041€ and 2,081 tCO2e respectively. A sensitivity analysis on landfilling gate fees highlighted that they should be significantly increased to incentivise higher recycling rates and close material loops. This research is the first to evaluate the effects of policy initiatives on the shaping of optimised reverse supply chains through mathematical programming methods. The work contributes to the waste management literature by designing optimal circular supply chain networks for the management of waste from wind turbines decommissioning at the EU-level to improve sustainability of renewable energy installations. [ABSTRACT FROM AUTHOR]

• Introduced a circular economy-based cost model for kerbside wastes. • Evaluated costs in closed-loop and open-loop recycling. • Demonstrated KGRSB cost less than KRMB model. • Alignment of cost model with attributional LCA model for kerbside waste recycling. Rapid expansion in urban areas has engendered a superfluity of municipal solid waste (MSW) stemming from contemporary civilization, encompassing commercial sectors and human undertakings. Kerbside waste, a type of MSW, has the potential for recycling and reuse at the end of its first life cycle, but is often limited to a linear cycle. This study aimed to assess the life cycle costs of different separation and recycling methods for handling kerbside waste. A new life cycle cost model, drawing from the circular economy's value retention process (VRP) model, has been created and applied to assess the continuous recycling of kerbside glass. The study investigates two key separation techniques, kerbside recycling mixed bin recycling (KRMB) kerbside glass recycling separate bin (KGRSB) and analyses their impact on the life cycle cost of the recycling process. Additionally, the research explores two approaches of recycling and downcycling: closed-loop recycling, which pertains to the recycling of glass containers, and open-looped recycling, which involves the use of recycled glass in asphalt. The results showed when use annually collected waste as the functional unit, the KRMB model incurred lower costs compared to the KGRSB model due to its lower production output. However, when evaluated over a 1-ton production of glass container and asphalt, the KGRSB method demonstrated superior cost performance with a 40–50% reduction compared to the KRMB method. The open-loop recycling method (asphalt) incurred a higher cost compared to the closed-loop recycling method due to its larger production volume over a 21-year period. [ABSTRACT FROM AUTHOR]

• This study proposes a model to consider quality degradation in glass recycling. • The model is based on technical quality substitutability and market applicability. • The model was applied to a case study on glass waste treatment. • Accounting for quality degradation, only 83% of cullet can replaces raw materials. • The decrease of recycling benefits was of 13–23% for the examined impact categories. The sustainability assessment of waste management systems requires tools capable of evaluating material quality degradation during recycling. Existing research has predominantly focused on the development of substitutability models for plastics, leaving a gap in addressing other materials like glass. Glass is commonly regarded as endlessly recyclable, even though its actual recyclability depends on several crucial factors, such as colour and pollutant contamination. Many Life Cycle Assessment (LCA) studies in this field assume a one-to-one substitution coefficient, neglecting material deterioration and inaccurately representing real-world scenarios. This study proposes and assesses a substitutability model for glass, aiming to measure the replacement extent between virgin materials and recycled crushed glass (cullet). The methodology is based on two key factors: technical quality substitutability, considering impurities and colour contaminations in cullet, and market applicability, accounting for market demand. Once formulated, the model was applied to a European case study on glass waste treatment. Two scenarios were considered: one assuming complete substitution between cullet and raw materials, the other incorporating quality degradation. Findings indicate that, accounting for quality degradation, only 83% of cullet effectively replaces raw materials, resulting in a decrease of the benefit associated with recycling of 13–23% for the different examined impact categories, compared to complete replacement assumption. This underscores the importance of considering quality deterioration in glass recycling impact assessments. [ABSTRACT FROM AUTHOR]

• The utilization characteristics of gold tailings were reviewed. • The recovery of valuable components from gold tailings was summarized. • The application of gold tailings in the field of materials was adumbrated. • A new process combining magnetic separation and cemented filling was proposed. Gold tailings are characterized by low-grade, complex composition, fine embedded particle size, environmental pollution, and large land occupation. This paper describes the mineralogical properties of gold tailings, including chemical composition, phase composition, particle size distribution, and microstructure; summarizes the recycling and utilization of components such as mica, feldspar, and valuable metals in gold tailings; reviews harmless treatment measures for harmful elements in gold tailings; and adumbrated the research progress of gold tailings in the application fields of building materials, ceramics, and glass materials. Based on these discussions, a new technology roadmap that combines multistage magnetic separation and cemented filling is proposed for the clean utilization of all components of gold tailings. [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]

• 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]

• Through enhanced IBA treatment extensive metal recovery is possible. • Bottom ashes from fluidized bed contain far more glass than from grate incineration. • Glass can be recovered from fluidized bed, but not from grate IBA. • Fluidized bed IBA is better suited for concrete production than grate IBA. Enhanced treatment of incineration bottom ashes (IBA) from municipal solid waste incineration can contribute to a circular economy since not only metals can be recovered but also glass for recycling. Moreover, the remaining mineral fraction can be utilized in concrete as manufactured aggregate. To evaluate the effects of an enhanced treatment, three IBAs from fluidized bed combustion (FB-IBAs) and three grate incineration bottom ashes (G-IBAs) were standardly treated in a jig and further processed on a pilot scale, including improved metal recovery and sensor-based glass separation. The removed glass fractions were weighed and their composition was assessed by means of manual sorting. The manufactured aggregate was also sorted manually and its total and leachate contents were determined before and after aging. Results showed general differences between FB-IBAs and G-IBAs. For G-IBAs, higher contents of heavy metals and residual metal pieces were determined, while the share of glass removed was low compared to FB-IBA. The treated mineral fractions from G-IBA contained more mineral agglomerates, whereas FB-IBAs contained more glass. However, the glass-fractions removed from FB-IBAs need further treatment to be accepted in glass recycling. Austrian limit values for utilization in concrete were met by all manufactured aggregates produced from FB-IBA, but only by one from G-IBA. Overall, the enhanced treatment in the study performed well compared to the literature. Nevertheless, further investigations are necessary to improve the recyclability of the recovered glass fractions and to determine the technical suitability of manufactured aggregates produced from IBAs. [ABSTRACT FROM AUTHOR]

• Methodology to automatically generate geo-located waste container maps. • Use of Computer Vision algorithms to detect waste containers. • Automatic division into locations with and without containers in city maps. • Robust model with consistent performance disregarding the container type. • System evaluated in eleven Spanish cities with an average accuracy of 89%. This paper describes the scientific achievements of a collaboration between a research group and the waste management division of a company. While these results might be the basis for several practical or commercial developments, we here focus on a novel scientific contribution: a methodology to automatically generate geo-located waste container maps. It is based on the use of Computer Vision algorithms to detect waste containers and identify their geographic location and dimensions. Algorithms analyze a video sequence and provide an automatic discrimination between images with and without containers. More precisely, two state-of-the-art object detectors based on deep learning techniques have been selected for testing, according to their performance and to their adaptability to an on-board real-time environment: EfficientDet and YOLOv5. Experimental results indicate that the proposed visual model for waste container detection is able to effectively operate with consistent performance disregarding the container type (organic waste, plastic, glass and paper recycling,...) and the city layout, which has been assessed by evaluating it on eleven different Spanish cities that vary in terms of size, climate, urban layout and containers' appearance. [ABSTRACT FROM AUTHOR]

• Detect-waste and classify-waste datasets benchmarks were introduced. • The quality of waste detection in various environments has been tested. • Semi-supervised training can boost classification of different types of waste. • Remarkable performance in waste detection is obtained by the two-stage framework. Waste pollution is one of the most significant environmental issues in the modern world. The importance of recycling is well known, both for economic and ecological reasons, and the industry demands high efficiency. Current studies towards automatic waste detection are hardly comparable due to the lack of benchmarks and widely accepted standards regarding the used metrics and data. Those problems are addressed in this article by providing a critical analysis of over ten existing waste datasets and a brief but constructive review of the existing Deep Learning-based waste detection approaches. This article collects and summarizes previous studies and provides the results of authors' experiments on the presented datasets, all intended to create a first replicable baseline for litter detection. Moreover, new benchmark datasets detect-waste and classify-waste are proposed that are merged collections from the above-mentioned open-source datasets with unified annotations covering all possible waste categories: bio, glass, metal and plastic, non-recyclable, other, paper , and unknown. Finally, a two-stage detector for litter localization and classification is presented. EfficientDet-D2 is used to localize litter, and EfficientNet-B2 to classify the detected waste into seven categories. The classifier is trained in a semi-supervised fashion making the use of unlabeled images. The proposed approach achieves up to 70% of average precision in waste detection and around 75% of classification accuracy on the test dataset. The code and annotations used in the studies are publicly available online 1 1 https://github.com/wimlds-trojmiasto/detect-waste.. [ABSTRACT FROM AUTHOR]

• Waste glass is used as a partial activator and as a mineral precursor in one-part AAMs. • Waste glass powder serves as an effective silica supplier in the solid activator. • Waste glass as a mineral precursor retards the early strength of one-part AAMs. • Waste glass-based one-part AAMs are 23% cheaper and 84% greener than OPC binders. The feasibility of the extensive recycling of waste glass in alkali-activated materials (AAMs) was evaluated. The waste glass was utilised in AAMs for two purposes: a partial activator and a mineral precursor. The waste glass was blended with commercial sodium hydroxide and then heated to produce the solid activator powder. The technical performance of waste glass-based activator was investigated to replace commercial sodium silicate, a common alkali-activator used in AAMs. The effect of waste glass using only as the activator (WGA) and using as both activator and precursor (WGAP) in fly ash/slag-based one-part AAMs was studied using strength and microstructure characterisations. A mass-cost and emission analysis of waste glass-based AAMs (WGA and WGAP) was conducted, comparing the results with ordinary Portland cement (OPC). Characterisation tests of waste glass-based activator showed the effective formation of sodium silicate minerals with the adequate dissolution of activator in water by releasing reactive alkali and silica. Both WGA and WGAP showed comparable strengths at 56 days with a denser microstructure under ambient curing. According to mass analysis, waste glass could be utilised up to 17% by mass of total binder. Based on the analysis of cost and CO 2 emissions, WGA and WGAP are around 23% and 15% cheaper and 84% and 82% greener than OPC. The dual role of waste glass in AAMs as an activator and as a precursor broadens the recycling of glass waste in the cement industry by favouring technical and environmental outcomes. [ABSTRACT FROM AUTHOR]

• Separation and recovery of polymeric fractions as backsheet and encapsulant. • Recycling of metallic silver and silicon from EVA residue. • 82% recycling rate, 94% recovery rate and 73% value recovery for EOL PVP treatment. The increase in the annual flux of the end-of-life photovoltaic panels (EoL-PVPs) imposed the development of effective recycling strategies to reach EU regulation targets (i.e. 80% recycling; 85% recovery, starting from August 2018). The recycling targets in a PVP are generally glass, photovoltaic cell and metals, while no scientific paper or patent addressed polymeric fractions recycling and recovery, i.e. encapsulant polymer (EVA) and backsheet (Tedlar), starting from preliminarily milled EoL-PVPs. In the present study an optimization following the solvent treatment operation of the basic Photolife process (demonstrated at pilot scale), was proposed (lab scale) and validated (micropilot scale), focusing on polymers separation and metals recovery. The optimization was performed by testing 4 different processes. Specifically, the selectivity of the filtration operation (subsequent the solvent treatment) on polymers separation grade was evaluated, demonstrating that Tedlar can be effectively separated from EVA residues. Moreover, in comparison to the basic Photolife, a further operation was introduced treating thermally the EVA residues (containing the PV cell). The metal extraction yields highlighted the effectiveness of that strategy in comparison with direct extraction from the uncombusted EVA residues. Processing 100 Kg of crushed material, 0.03 Kg of Ag, 45.5 Kg of high value glass, 10 Kg of Al scraps and 1.2 Kg of metallic filaments can be recovered. Thanks to the optimization the recycling rate of the implemented process grew up to 82% (75% during demonstration of the basic Photolife process), while the recovery was estimated at 94%. Remarkably, these rates get over with EU Directive. [ABSTRACT FROM AUTHOR]

• Ex-ante analysis of recycling and recovery infrastructures for GFRP/CFRP waste. • Impacts of potential political regulations. • Impacts of potential markets for secondary materials. • Optimal choice of recycling and recovery options for GFRP/CFRP waste. Establishing recycling and recovery infrastructures for innovative materials like high-performance composites is very challenging. For such materials, recycling and recovery infrastructures are not yet established, research on end-of-life treatment technologies is still in the development state, and secondary markets for recycled materials are still missing. Against this background, we provide an ex-ante analysis on the design of future cost-minimal recycling and recovery infrastructures for glass (GFRP) and carbon (CFRP) fiber reinforced plastic waste from rotor blades of wind power plants based on a mathematical optimization model. We present insights into future capacities and technologies for the recycling and recovery infrastructures within the EU-28. We systematically analyze the impacts of political regulations and of secondary markets on the design of these infrastructures. While future recycling of CFRP mainly depends on the development of secondary markets independent of political regulations, GFRP is mainly combusted in incineration plants or co-processed in cement clinker plants. Hence, political decision makers should focus on providing measures that support the development of secondary markets for recycled carbon fibers and provide incentives for co-processing of GFRP to overcome capacity limitations. [ABSTRACT FROM AUTHOR]

• Waste mixing during glass dump excavation jeopardizes resource recovery potential. • ERT can detect glass hotspots for careful excavation to avoid costly waste sorting steps. • Glass and bedrock resistivity similarities require caution when interpreting ERT data. • Resistivity discrepancies introduce artifacts, causing increased uncertainty with depth. • ERT is applicable to glass dumps given their shallowness (less uncertainty near surface). This study investigates the potential for Electrical Resistivity Tomography (ERT) to detect buried glass 'hotspots' in a glass waste dump based on results from an open glass dump investigated initially. This detection potential is vital for excavation and later use of buried materials as secondary resources. After ERT, test pits (TPs) were excavated around suspected glass hotspots and physico-chemical characterisation of the materials was done. Hotspots were successfully identified as regions of high resistivity (>8000 Ωm) and were thus confirmed by TPs which indicated mean glass composition of 87.2% among samples (up to 99% in some). However, high discrepancies in material resistivities increased the risk for introduction of artefacts, thus increasing the degree of uncertainty with depth, whereas similarities in resistivity between granite bedrock and crystal glass presented data misinterpretation risks. Nevertheless, suitable survey design, careful field procedures and caution exercised by basing data interpretations primarily on TP excavation observations generated good results particularly for near-surface materials, which is useful since glass waste dumps are inherently shallow. Thus, ERT could be a useful technique for obtaining more homogeneous excavated glass and other materials for use as secondary resources in metal extraction and other waste recycling techniques while eliminating complicated and often costly waste sorting needs. [ABSTRACT FROM AUTHOR]

• Indium can be recycled from waste LCD panel by an integrated recovery process. • Indium recovery includes leaching and purification after hydrothermal pretreatment. • Acid leaching under optimal conditions can achieve 100% leaching yield of indium. • Recovery efficiency of indium reaches 97.25% under optimal purification parameters. • The integrated process of indium recovery does not affect glass recovery. Indium is one of the components with great recycling value in waste LCDs. Degradation of organic materials and the remain of indium in the solid phase can be simultaneously achieved by hydrothermal pretreatment via parameter regulation. Indium was transferred from the solid phase to the liquid phase by using sulfuric acid after hydrothermal pretreatment. Di-(2-ethylhexyl) phosphoric acid diluted by sulfonated kerosene and hydrochloric acid were used as extractant and stripping agent respectively to purify and concentrate indium from acidic leaching solution. The results indicated that the leaching yield of indium reached 100% under the optimal condition of reaction time of 40 min, reaction temperature of 70–80 °C, acid concentration of 0.5 M and solid-liquid (S/L) ratio of 1:2 g/mL. Given conditions of extraction time of 3 min at the organic phase to aqueous phase (O/A) ratio of 1:10 by 20% D2EHPA and stripping time of 10 min at the (O/A) ratio of 10:1 by 4 M HCl, the recovery efficiency of indium reached 97.25%. In addition, acid leaching process did not change the surface topography and molecular structure of glass substrate and had no negative effect on subsequent recycling of glass. The kinetic equation of leaching yield and reaction time at the temperature of 80 °C is 1 − (1 − y)1/3 = 0.0215 t. The reaction activation energy of metal indium leaching process is 50.64 kJ/mol. [ABSTRACT FROM AUTHOR]

Highlights • Framework was developed for efficient waste management in construction industry. • Mechanical performance was evaluated for glass-incorporated concrete. • CO 2 footprint and volume of non-renewable raw materials were also assessed. • Sustainable concrete was selected by mechanical-environmental performance. • Analytical techniques were applied for verification of proposed framework. Abstract This work was designed to incorporate glass waste as partial replacement of coarse aggregate in concrete through optimization of its amount by assessment of mechanical and environmental performances. Fresh and hardened properties of glass waste concrete were evaluated and compared with the conventional concrete. Moreover, compressive strength was evaluated experimentally as well as analytically at different ages. While, environmental performance was evaluated with an assessment of CO 2 footprint and volume utilization of raw materials for both types of concrete; conventional and glass waste concrete. Consequently, a sustainable concrete was selected that possesses high workability and mechanical performance, minimum CO 2 footprint and least utilization of conventional natural raw materials. For optimization, corresponding values of designed parameters were translated into a framework for glass waste management by application of analytical hierarchy process (AHP) and technique for order preference by similarity to ideal solution (TOPSIS). Similar prioritization for all types of mixtures was achieved through proposed framework by applying such multi criteria decision making techniques. Proposed framework may further be used for adjusting the priority weights for each criterion according to the requirement as well as for extended evaluation of additional criteria. [ABSTRACT FROM AUTHOR]

The present paper deals with physico-mechanical pre-treatments for dismantling of spent liquid crystal displays (LCDs) and further recovery of valuable fractions like plastic, glass and indium. After a wide experimental campaign, two processes were designed, tested and optimized. In the wet process, 20%, 15% and 40% by weight of the feeding panels are recovered as plastic, glass and indium concentrate, respectively. Instead, in the dry process, only two fractions were separated: around 11% and 85% by weight are recovered as plastic and glass/indium mixture. Indium, that concentrated in the −212 μm fraction, was completely dissolved by sulphuric acid leaching (0.75 mol L −1 H 2 SO 4 solution, 80 °C, 10%vol H 2 O 2 , pulp density 10%wt/vol, leaching time 3 h). 100% of indium can be extracted from the pregnant solution with 5%wt/vol Amberlite™ resin, at room temperature and pH 3 in 24 h. Indium was thus re-extracted from the resin by means of a 2 mol L −1 H 2 SO 4 solution, at room temperature and S/L of 40%wt/vol. [ABSTRACT FROM AUTHOR]

Considering indium scarcity, the end-of-life (EOL) LCD, which accounts for up to 90% of market share can be a feasible secondary resource upon successful recycling. In the preferred hydrometallurgical process of such critical metals, leaching is the essential primary and essential phase has been investigated. In this process, LCD was mechanically separated along with other parts from EOL TVs through a smartly engineered process developed at our institute, Institute for Advanced Engineering (IAE), the Republic of Korea. After removing plastics and metals from the LCD, it was mechanically shredded for size reduction. The mechanically shredded LCD waste was leached with HCl for recovery of indium. Possible leaching parameters such as; effect of acid concentration, pulp density, temperature and effect of oxidant H 2 O 2 concentration were investigated to identify the best conditions for indium extraction. Indium (76.16 × 10 −3 g/L) and tin (10.24 × 10 −3 g/L) leaching was achieved at their optimum condition, i.e. lixiviant of 5 M HCl, a pulp density of 500 g/L, temperature 75 °C, agitation speed of 400 rpm and time for 120 min. At optimum condition the glass, plastic and the valuable metal indium have completely been separated. From indium enriched leach liquor, indium can be purified and recovered through hydrometallurgy. [ABSTRACT FROM AUTHOR]

Insights derived from life-cycle assessment of solid waste management strategies depend critically on assumptions, data, and modeling at the unit process level. Based on new primary data, a process model was developed to estimate the cost and energy use associated with material recovery facilities (MRFs), which are responsible for sorting recyclables into saleable streams and as such represent a key piece of recycling infrastructure. The model includes four modules, each with a different process flow, for separation of single-stream, dual-stream, pre-sorted recyclables, and mixed-waste. Each MRF type has a distinct combination of equipment and default input waste composition. Model results for total amortized costs from each MRF type ranged from $19.8 to $24.9 per Mg (1 Mg = 1 metric ton) of waste input. Electricity use ranged from 4.7 to 7.8 kW h per Mg of waste input. In a single-stream MRF, equipment required for glass separation consumes 28% of total facility electricity consumption, while all other pieces of material recovery equipment consume less than 10% of total electricity. The dual-stream and mixed-waste MRFs have similar electricity consumption to a single-stream MRF. Glass separation contributes a much larger fraction of electricity consumption in a pre-sorted MRF, due to lower overall facility electricity consumption. Parametric analysis revealed that reducing separation efficiency for each piece of equipment by 25% altered total facility electricity consumption by less than 4% in each case. When model results were compared with actual data for an existing single-stream MRF, the model estimated the facility’s electricity consumption within 2%. The results from this study can be integrated into LCAs of solid waste management with system boundaries that extend from the curb through final disposal. [ABSTRACT FROM AUTHOR]

Highlights: [•] This paper aims to find the most efficient market structure for waste recycling in Portugal. [•] Some economies of output density and some economies of size were found in this study. [•] The utilities should especially increase the quantities of glass for recycling. [•] The results show that utilities should become larger. [•] Private management and incineration seem to reduce the costs of utilities. [ABSTRACT FROM AUTHOR]

Highlights: [•] The compressive strength of CRT-Concrete exceeds that of the control specimens. [•] The workability of the concrete is affected by the addition of CRT glass. [•] A maximum of 10% CRT glass should be used to avoid ASR expansions. [•] Lead leaching from CRT-Concrete is pH dependent. [•] Use of biopolymer solutions help reduce lead leaching from CRT-Concrete. [Copyright &y& Elsevier]

Abstract: Cathode Ray Tube, CRT, waste glass recycling has plagued glass manufacturers, electronics recyclers and electronics waste policy makers for decades because the total supply of waste glass exceeds demand, and the formulations of CRT glass are ill suited for most reuse options. The solutions are to separate the undesirable components (e.g. lead oxide) in the waste and create demand for new products. Achieving this is no simple feat, however, as there are many obstacles: limited knowledge of waste glass composition; limited automation in the recycling process; transportation of recycled material; and a weak and underdeveloped market. Thus one of the main goals of this paper is to advise electronic glass recyclers on how to best manage a diverse supply of glass waste and successfully market to end users. Further, this paper offers future directions for academic and industry research. To develop the recommendations offered here, a combination of approaches were used: (1) a thorough study of historic trends in CRT glass chemistry; (2) bulk glass collection and analysis of cullet from a large-scale glass recycler; (3) conversations with industry members and a review of potential applications; and (4) evaluation of the economic viability of specific uses for recycled CRT glass. If academia and industry can solve these problems (for example by creating a database of composition organized by manufacturer and glass source) then the reuse of CRT glass can be increased. [Copyright &y& Elsevier]

Abstract: As part of the EU Life + NOVEDI project, a new eco-efficient recycling route has been implemented to maximise resources and energy recovery from post-consumer waste glass, through integrated waste management and industrial production. Life cycle assessment (LCA) has been used to identify engineering solutions to sustainability during the development of green building products. The new process and the related LCA are framed within a meaningful case of industrial symbiosis, where multiple waste streams are utilised in a multi-output industrial process. The input is a mix of rejected waste glass from conventional container glass recycling and waste special glass such as monitor glass, bulbs and glass fibres. The green building product is a recycled foam glass (RFG) to be used in high efficiency thermally insulating and lightweight concrete. The environmental gains have been contrasted against induced impacts and improvements have been proposed. Recovered co-products, such as glass fragments/powders, plastics and metals, correspond to environmental gains that are higher than those related to landfill avoidance, whereas the latter is cancelled due to increased transportation distances. In accordance to an eco-efficiency principle, it has been highlighted that recourse to highly energy intensive recycling should be limited to waste that cannot be closed-loop recycled. [Copyright &y& Elsevier]

Abstract: A comprehensive suite of geotechnical laboratory tests was undertaken on samples of recycled crushed glass produced in Victoria, Australia. Three types of recycled glass sources were tested being coarse, medium and fine sized glass. Laboratory testing results indicated that medium and fine sized recycled glass sources exhibit geotechnical behavior similar to natural aggregates. Coarse recycled glass was however found to be unsuitable for geotechnical engineering applications. Shear strength tests indicate that the fine and medium glass encompass shear strength parameters similar to that of natural sand and gravel mixtures comprising of angular particles. Environmental assessment tests indicated that the material meets the requirements of environmental protection authorities for fill material. The results were used to discuss potential usages of recycled glass as a construction material in geotechnical engineering applications particularly road works. [Copyright &y& Elsevier]

Abstract: In this study, wasted glasses from structural glass walls up to 45wt.% were added into clay mixtures in brick manufacturing process. Physical and mechanical properties of clay bricks were investigated as functions of the wasted glass content and the firing temperature. The results indicated that with proper amount of wasted glasses and firing temperature, clay bricks with suitable physical and mechanical properties could be obtained. The compressive strength as high as 26–41MPa and water absorption as low as 2–3% were achieved for bricks containing 15–30wt.% of glass content and fired at 1100°C. When the glass waste content was 45wt.%, apparent porosity and water absorption was rapidly increased. [Copyright &y& Elsevier]

Mixed glass cullet (crushed recycled glass containers) is stockpiled uncovered before use as roadway construction aggregate or daily cover in landfills. Rainwater that leaches through the stockpiles dissolves and suspends contaminants such as those from food residuals and paper labels. The objective of this study was to determine leachate quantity and quality from cullet stockpiles as a basis for development of Best Management Practices (BMPs). Four 35-tonne field stockpiles were set up for leachate analysis and to determine the effects of mechanical turning treatment on the leachate. Field-collected leachate and laboratory-generated washwater of cullet (water:cullet=3:1 by weight) were both analyzed for basic wastewater parameters, which showed pollutant levels comparable to or higher than those of untreated domestic wastewater or urban stormwater. While organic contamination decreased substantially (e.g., washwater BOD>95% reduction), TKN and total-phosphorus levels in leachate ranged between 11.6–154mgL−1 and 1.6–12.0mgL−1, respectively, and remained comparable to levels found in untreated domestic wastewater after four months. Turning enhanced the degradation of the organic constituents inside the stockpiles, which was confirmed by elevated temperatures. Based on this study, leachate from glass cullet stockpiles should not be released to surface water. For leachate from long-term cullet stockpiles, release to groundwater should be only done after treatment to reduce nitrogen levels. [Copyright &y& Elsevier]

Abstract: Use of waste glass or glass cullet (GC) as concrete aggregate is becoming more widespread each day because of the increase in resource efficiency. Recycling of wastes is very important for sustainable development. When glass is used as aggregate in concrete or mortar, expansions and internal stresses occur due to an alkali–silica reaction (ASR). Furthermore, rapid loss in durability is generally observed due to extreme crack formation and an increase in permeability. It is necessary to use some kind of chemical or mineral admixture to reduce crack formation. In this study, mortar bars are produced by using three different colors of glass in four different quantities as fine aggregate by weight, and the effects of these glass aggregates on ASR are investigated, corresponding to ASTM C 1260. Additionally, in order to reduce the expansions of mortars, 10% and 20% fly ash (FA) as mineral admixture and 1% and 2% Li2CO3 as chemical admixture are incorporated by weight in the cement and their effects on expansion are examined. It is observed that among white (WG), green (GG) and brown glass (BG) aggregates, WG aggregate causes the greatest expansion. In addition, expansion increases with an increase in amount of glass. According to the test results, it is seen that over 20% FA and 2% Li2CO3 replacements are required to produce mortars which have expansion values below the 0.2% critical value when exposed to ASR. However, usages of these admixtures reduce expansions occurring because of ASR. [Copyright &y& Elsevier]

Waste glass creates a serious environmental problem, mainly because of the inconsistency of the waste glass streams. The use of waste glass as a finely ground mineral additive (FGMA) in cement is a promising direction for recycling. Based on the method of mechano-chemical activation, a new group of ECO-cements was developed. In ECO-cement, relatively large amounts (up to 70%) of portland cement clinker can be replaced with waste glass. This report examines the effect of waste glass on the microstructure and strength of ECO-cement based materials. Scanning electron microscopy (SEM) investigations were used to observe the changes in the cement hydrates and interface between the cement matrix and waste glass particles. According to the research results, the developed ECO-cement with 50% of waste glass possessed compressive strength properties at a level similar to normal portland cement. [Copyright &y& Elsevier]

Abstract: The presence of ceramic glass contaminants in glass recycling plants reduces production quality and increases production costs. The problem of ceramic glass inspection is related to the fact that its detectable physical and pictorial properties are quite similar to those of glass. As a consequence, at the sorting plant scale, ceramic glass looks like normal glass and is detectable only by specialized personnel. In this paper an innovative approach for ceramic glass recognition, based on imaging spectroscopy, is proposed and investigated. In order to define suitable inspection strategies for the separation between useful (glass) and polluting (ceramic glass) materials, reference samples of glass and ceramic glass presenting different colors, thicknesses, shapes and manufacturing processes have been selected. Reflectance spectra have been obtained using two equipment covering the visible and near infrared wavelength ranges (400–1000 and 1000–1700nm). Results showed as recognition of glass and ceramic glass is possible using selected wavelength ratios, in both visible and near infrared fields. [Copyright &y& Elsevier]

Vitrification and production of ceramics materials starting from sediment excavated from Venice lagoon is described. This sediment is classified as toxic waste because contains several heavy metal ions and organic pollutants and was successfully vitrified at 1200–1350 °C. Twenty weight percentage of glass cullet, coming from a community glass recycling program, was added to the raw materials, previously calcined at 900 °C, as a way of adjusting the variations of composition of the individual sediment batches. Chemical durability (leaching) tests showed that the optimized glass compositions are inert, and thus not only volume reduction but also inertization of the waste was obtained by this process. Moreover, the economics of the entire process was analysed. The valorization of the waste was accomplished by the subsequent processing of the glass derived from the inertization. Glass ceramic materials were produced by viscous phase sintering of pressed glass powders which crystallized during the densification process. Sintered glass ceramic products had good mechanical characteristics (HV=7.5 GPa, bending strength 150±8 MPa), making them suitable for applications in the building industry. [Copyright &y& Elsevier]