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The aim of this paper is to investigate the flexural performance of a new steel–concrete composite beam system, which is required to carry higher loads when applied in flooring systems with less self-weight and cost compared with conventional composite beams. This new composite member is prepared by filling a single cold-formed steel C-section with concrete material that has varied lightweight-recycled aggregates. In addition, varied stiffening scenarios are suggested to improve the composite behavior of this member, since these cold-formed C-sections are of a slender cross-section and more likely to buckle and twist under high bending loads than those of hot-rolled C-sections. The influence of using four different lightweight-recycled aggregates that combine together in the infill concrete material was investigated. These recycled aggregates are recycled concrete aggregate (RCA), expanded polystyrene (EPS) beads, crumb rubber aggregates (CRA) and fine glass aggregates (FGA). For this purpose, 14 samples of cold-formed galvanized steel C-purlin were filled with concrete material (containing 0 to 100% recycled aggregates) which are experimentally tested under pure bending load, and 1 additional sample was tested without the filling material. Further numerical models were prepared and analyzed using finite element analysis software to investigate the effects of additional parameters that were not experimentally examined. Generally, the results confirm that filling the C-sections with concrete material that contains varied percentages of recycled aggregates offer significantly improved the flexural stiffness, bending capacity, and ductility performances. For example, using infill concrete materials with 0% and 100% recycled aggregate replacement increased the bending capacity of hollow C-section by about 11.4 and 8.6 times, respectively. Furthermore, stiffening of the concrete-filled C-sections with steel strips or screw connectors eventually improved the compo

Landfilling of mine and industrial waste streams leads to environmental and economic issues. Sustainable management methods through valorization in manufacturing green construction materials are a current research interest. Here, a promising process for recycling mine tailings, such as phosphate sludge, is proposed. A mixture of phosphate sludge, kaolin clay (Al source), and glass waste (Si source) was prepared. Three fluxing agents were tested at 1000 °C (NaOH, Na2CO3, Na2SO4). Na2CO3 was selected as the most cost-effective. The precursors were alkaline activated with NaOH solution (2, 6, and 8 M). At 28 days of curing (20 h room temperature + 6 h 85 °C + room temperature), the best compressive strength (of more than 45 MPa) was obtained with 8 M NaOH. The reaction products, characterized by XRD, FTIR, SEM, and MAS NMR, show that the main reaction products is a gel N–A–S–H/(N,C)–A–S–H together with some unreacted crystalline phases formed during the fusion.

This paper presents the casting of volumetric glass components from glass waste as an alternative glass-recycling approach. The approach is characterized by its flexibility to accommodate a variety of compositions and ability to yield volumetric (solid or thick-walled) glass products that can tolerate higher contamination rates without a significant compromise to their properties. The novelty of the proposed glass-to-glass recycling method lies in the “as-received” recycling of glass waste, using relatively low forming temperatures (750–1200 °C). This reduces both the need for expensive, labour-intensive and logistically complex purifying, segregation and treatment (e.g. removal of coatings) techniques, and the required energy and CO2 emissions for product forming. Aim of this paper is to provide an overview of the potential but also of the technical and supply-chain challenges and limitations that still need to be tackled, in order to introduce this recycling approach to the market. Addressing the supply-chain barriers of glass recycling, the principal challenges linked to the collection and separation of glass waste and the established quality standards for the prevailing glass production technologies are identified, in order to argue upon the potential of this new recycling approach. In continuation, addressing the technical challenges that are mainly linked to contamination, an overview is provided of the main experimental findings on the influence of cullet contaminants and casting parameters on the generation of defects, and how these affect the mechanical properties. The experiments study a broad variety of glass compositions, including soda-lime, borosilicate, aluminosilicate and lead/barium glasses, and different levels of cullet contamination, of embedded (e.g. frit, wire) or external (e.g. stones, glass ceramics) character. Based on the cullet characteristics and imposed firing schedules, different glass quality grades arise and critical def, Structural Design & Mechanics

Landfilling of mine and industrial waste streams leads to environmental and economic issues. Sustainable management methods through valorization in manufacturing green construction materials are a current research interest. Here, a promising process for recycling mine tailings, such as phosphate sludge, is proposed. A mixture of phosphate sludge, kaolin clay (Al source), and glass waste (Si source) was prepared. Three fluxing agents were tested at 1000 °C (NaOH, NaCO, NaSO). NaCO was selected as the most cost-effective. The precursors were alkaline activated with NaOH solution (2, 6, and 8 M). At 28 days of curing (20 h room temperature + 6 h 85 °C + room temperature), the best compressive strength (of more than 45 MPa) was obtained with 8 M NaOH. The reaction products, characterized by XRD, FTIR, SEM, and MAS NMR, show that the main reaction products is a gel N–A–S–H/(N,C)–A–S–H together with some unreacted crystalline phases formed during the fusion.

The development of alternative materials for the construction industry, based on different types of waste, is gaining significant importance in recent years. This is mostly due to the need to increase sustainability of this heavily polluting activity, thus mitigating the dependence on, for instance, Portland cement. The present paper is related to the development of an alkaline activated cement (AAC) exclusively fabricated from industrial by-products (both precursor and activator). Coal combustion fly ash, a common residue from thermoelectric powerplants, and glass waste, from the manufacture of ophthalmic lenses, were used as precursors. These precursors were activated with a recycled alkaline solution, resulting from the cleaning of aluminium extrusion dies, instead of the more common commercial reagents usually applied for this type of binder. Several pastes were studied, combining the precursor and alkaline solution in different proportions. When the most-performing cements were defined, they were used to stabilise a cohesive soil. The experimental procedure and subsequent analysis were designed based on a Response Surface Methodology model, considering the Activator/Solids and Soil/Precursor ratios as the most relevant variables of the stabilisation process. It was observed that, depending on the type of alkaline cement used, there was an optimum precursor and activator contents to optimise the mechanical properties of the stabilised soil. The reliability of this prediction was especially dependent on the type of precursors and, also, on their respective dissolution process right before the homogenization with the soil, under the working conditions available.

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.

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.

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.

Around former glass factories in south eastern Sweden, there are dozens of dumps whose radioactivity and physico-chemical properties were not investigated previously. Thus, radiometric and physico-chemical characteristics of waste at Madesjö glass dump were studied to evaluate pre-recycling storage requirements and potential radiological and environmental risks. The material was sieved, hand-sorted, leached and scanned with X-Ray Fluorescence (XRF). External dose rates and activity concentrations of Naturally Occurring Radioactive Materials from 238U, 232Th series and 40K were also measured coupled with a radiological risk assessment. Results showed that the waste was 95% glass and dominated by fine fractions (< 11.3 mm) at 43.6%. The fine fraction had pH 7.8, 2.6% moisture content, 123 mg kg-1 Total Dissolved Solids, 37.2 mg kg-1 Dissolved Organic Carbon and 10.5 mg kg-1 fluorides. Compared with Swedish EPA guidelines, the elements As, Cd, Pb and Zn were in hazardous concentrations while Pb leached more than the limits for inert and non-hazardous wastes. With 40K activity concentration up to 3000 Bq kg-1, enhanced external dose rates of 40K were established (0.20 mSv h-1) although no radiological risk was found since both External Hazard Index (Hex) and Gamma Index (Iγ) were < 1. The glass dump needs remediation and storage of the waste materials under a safe hazardous waste class ‘Bank Account’ storage cell as a secondary resource for potential future recycling.

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.

The use of non-biodegradable waste such as glass and plastic in the construction industry has received significant attention for a cleaner environment. This work presents a study of bricks’; mechanical properties containing aggregates, glass, and polyethylene terephthalate pellets. The bricks were melted at a temperature up to 240 ° C for 3 hours and cooled by natural convection. The results showed that an increase in the content of glass and aggregates generates an increase in density, being higher in the samples with a higher aggregates content. The same trend was observed in compressive strength. The sample with the highest aggregates’; content showed an improvement of 243% compared to the reference (prepared only with plastic). The results indicated that carbon dioxide emissions decreased by around 30% in the prepared samples, compared to traditional bricks. The use of plastic and glass waste in brick production is expected to become a recovery route., El uso de desechos no biodegradables como el vidrio y el plástico en la industria de la construcción ha recibido atención significativa para un medio ambiente más limpio. Este trabajo presenta un estudio de las propiedades mecánicas de ladrillos que contienen agregados, vidrio y pellets de tereftalato de polietileno. Los ladrillos se fundieron a 240 °C durante 3 horas y se enfriaron por convección natural. Los resultados mostraron que un aumento en el contenido de vidrio y agregados genera un incremento en la densidad, que es superior en las muestras con mayor contenido de agregados. La misma tendencia se observó en la resistencia a la compresión: la muestra con mayor contenido de agregados mostró una mejora del 243 % comparada con la referencia (preparada solo con plástico). Los resultados indicaron que las emisiones de dióxido de carbono disminuyeron alrededor del 30 % en las muestras preparadas, en comparación con los ladrillos tradicionales. Se espera que el uso de residuos de plástico y vidrio en la producción de ladrillos se convierta en una ruta para su valorización

The use of non-biodegradable waste such as glass and plastic in the construction industry has received significant attention for a cleaner environment. This work presents a study of bricks’; mechanical properties containing aggregates, glass, and polyethylene terephthalate pellets. The bricks were melted at a temperature up to 240 ° C for 3 hours and cooled by natural convection. The results showed that an increase in the content of glass and aggregates generates an increase in density, being higher in the samples with a higher aggregates content. The same trend was observed in compressive strength. The sample with the highest aggregates’; content showed an improvement of 243% compared to the reference (prepared only with plastic). The results indicated that carbon dioxide emissions decreased by around 30% in the prepared samples, compared to traditional bricks. The use of plastic and glass waste in brick production is expected to become a recovery route., El uso de desechos no biodegradables como el vidrio y el plástico en la industria de la construcción ha recibido atención significativa para un medio ambiente más limpio. Este trabajo presenta un estudio de las propiedades mecánicas de ladrillos que contienen agregados, vidrio y pellets de tereftalato de polietileno. Los ladrillos se fundieron a 240 °C durante 3 horas y se enfriaron por convección natural. Los resultados mostraron que un aumento en el contenido de vidrio y agregados genera un incremento en la densidad, que es superior en las muestras con mayor contenido de agregados. La misma tendencia se observó en la resistencia a la compresión: la muestra con mayor contenido de agregados mostró una mejora del 243 % comparada con la referencia (preparada solo con plástico). Los resultados indicaron que las emisiones de dióxido de carbono disminuyeron alrededor del 30 % en las muestras preparadas, en comparación con los ladrillos tradicionales. Se espera que el uso de residuos de plástico y vidrio en la producción de ladrillos se convierta en una ruta para su valorización

Waste reuse is considered an excellent alternative for sustainable development. For the World Commission on Environment and Development in Our Common Future, sustainability is "one that meets the needs of the present without compromising the ability of future generations to meet their needs." One way to provide a sustainable solution for glass would be the reuse of glass waste in the production of concrete. Glass residues when suitably crushed and sieved, to assume appropriate granulometry, may exhibit characteristics similar to natural aggregates. The use of glass waste when used in concrete manufacturing reduces production costs. The main objective of the research was to replace, as much as possible, in percentage, the quantity of sand and gravel aggregates by glass waste with the same granulometry, as a way to reduce costs, reduce the use of raw materials and reduce the quantity of wastes that were inadequately disposed of in landfills. Samples of glass waste were collected in the construction industry itself, in works and glassware companies that work with cutting and delivery of the product. Comparisons were made between concretes produced with natural and concrete aggregates produced with the substitution of 20%, 30%, 40% and 50% of the fine aggregate, all of which glass was used as a substitute. The comparative analyzes were the mechanical properties of compression strength and diametral compression traction at 7, 14, 21, 28 and 90 days.

Physico-chemical characteristics of waste, particularly fine fraction (FF), from an old crystal glass waste dump in Sweden were studied to assess recycling or disposal alternatives. Hand-sorting of the waste indicated glass content of 44.1% while sieving established the FF as a more soil-like mix of glass and other materials constituting 33.3% of all excavated waste. The FF was around neutral pH with 24.4% moisture content, low values of Total Dissolved Solids, Dissolved Organic Carbon and fluorides, but hazardous concentrations of As, Cd, Pb and Zn according to the Swedish Environmental Protection Agency guidelines. While the FF leached metals in low concentrations at neutral pH, it leached considerably during digestion with nitric acid, implying leaching risks at low pH. Thus, the waste requires safe storage in hazardous waste class ‘bank account’ storage cells to avoid environmental contamination as metal recovery and other recycling strategies for the glass waste are being developed. The study could fill the information gap regarding preservation of potential resources in the on-going, fast-paced excavation and re-landfilling of heavy metal contaminated materials in the region.

Physico-chemical characteristics of waste, particularly fine fraction (FF), from an old crystal glass waste dump in Sweden were studied to assess recycling or disposal alternatives. Hand-sorting of the waste indicated glass content of 44.1% while sieving established the FF as a more soil-like mix of glass and other materials constituting 33.3% of all excavated waste. The FF was around neutral pH with 24.4% moisture content, low values of Total Dissolved Solids, Dissolved Organic Carbon and fluorides, but hazardous concentrations of As, Cd, Pb and Zn according to the Swedish Environmental Protection Agency guidelines. While the FF leached metals in low concentrations at neutral pH, it leached considerably during digestion with nitric acid, implying leaching risks at low pH. Thus, the waste requires safe storage in hazardous waste class ‘bank account’ storage cells to avoid environmental contamination as metal recovery and other recycling strategies for the glass waste are being developed. The study could fill the information gap regarding preservation of potential resources in the on-going, fast-paced excavation and re-landfilling of heavy metal contaminated materials in the region.

Risks associated with metal contaminated sites are tightly linked to material leachability and contaminant mobility. In this study, metal solubility and transport were characterized within a glass waste landfill through i) lysimeter-collection of pore water and standardized batch leaching tests, ii) soil profiles extending from the landfill surface, through unsaturated soil underneath, and into the groundwater zone, and iii) groundwater samples upstream, at, and downstream of the landfill. The soil analyzes targeted both pseudo-total and geochemically active concentrations of contaminant metals (As, Cd, Pb, Sb) and basic soil geochemistry (pH, org. C, Fe,Mn). Water samples were analyzed for dissolved, colloid-bound and particulate metals, and speciation modelling of the aqueous phase was conducted. The results revealed a highly contaminated system, with mean metal concentrationsin the waste zone between 90 and 250 times the regional background levels. Despite severe contamination of the waste zone and high geochemically active fractions (80–100%) of all contaminant metals as well as elevated concentrations in landfill pore water, the concentrations of Cd and Pb decrease abruptly at the transition between landfill and underlying natural soil and no indication of groundwater contamination was found. The efficient cation retention is likely due to the high pH. However, the sorption of As and Sb is weaker at such high pH,which explains their higher mobility from the pore water zone into groundwater. The field soil:solution for Pb, ranging from 140 to 2,900,000 l kg−1), despite little variability in basic geochemical variables, which we suggest is due to waste material heterogeneity.

Risks associated with metal contaminated sites are tightly linked to material leachability and contaminant mobility. In this study, metal solubility and transport were characterized within a glass waste landfill through i) lysimeter-collection of pore water and standardized batch leaching tests, ii) soil profiles extending from the landfill surface, through unsaturated soil underneath, and into the groundwater zone, and iii) groundwater samples upstream, at, and downstream of the landfill. The soil analyzes targeted both pseudo-total and geochemically active concentrations of contaminant metals (As, Cd, Pb, Sb) and basic soil geochemistry (pH, org. C, Fe,Mn). Water samples were analyzed for dissolved, colloid-bound and particulate metals, and speciation modelling of the aqueous phase was conducted. The results revealed a highly contaminated system, with mean metal concentrationsin the waste zone between 90 and 250 times the regional background levels. Despite severe contamination of the waste zone and high geochemically active fractions (80–100%) of all contaminant metals as well as elevated concentrations in landfill pore water, the concentrations of Cd and Pb decrease abruptly at the transition between landfill and underlying natural soil and no indication of groundwater contamination was found. The efficient cation retention is likely due to the high pH. However, the sorption of As and Sb is weaker at such high pH,which explains their higher mobility from the pore water zone into groundwater. The field soil:solution for Pb, ranging from 140 to 2,900,000 l kg−1), despite little variability in basic geochemical variables, which we suggest is due to waste material heterogeneity.

Risks associated with metal contaminated sites are tightly linked to material leachability and contaminant mobility. In this study, metal solubility and transport were characterized within a glass waste landfill through i) lysimeter-collection of pore water and standardized batch leaching tests, ii) soil profiles extending from the landfill surface, through unsaturated soil underneath, and into the groundwater zone, and iii) groundwater samples upstream, at, and downstream of the landfill. The soil analyzes targeted both pseudo-total and geochemically active concentrations of contaminant metals (As, Cd, Pb, Sb) and basic soil geochemistry (pH, org. C, Fe, Mn). Water samples were analyzed for dissolved, colloid-bound and particulate metals, and speciation modelling of the aqueous phase was conducted. The results revealed a highly contaminated system, with mean metal concentrations in the waste zone between 90 and 250 times the regional background levels. Despite severe contamination of the waste zone and high geochemically active fractions (80-100%) of all contaminant metals as well as elevated concentrations in landfill pore water, the concentrations of Cd and Pb decrease abruptly at the transition between landfill and underlying natural soil and no indication of groundwater contamination was found. The efficient cation retention is likely due to the high pH. However, the sorption of As and Sb is weaker at such high pH, which explains their higher mobility from the pore water zone into groundwater. The field soil:solution partitioning (Kd) displayed a high spatial variability within the waste zone (the highest Kd variability was seen for Pb, ranging from 140 to 2,900,000 1 kg(-1)), despite little variability in basic geochemical variables, which we suggest is due to waste material heterogeneity.

Waste reuse is considered an excellent alternative for sustainable development. For the World Commission on Environment and Development in Our Common Future, sustainability is "one that meets the needs of the present without compromising the ability of future generations to meet their needs." One way to provide a sustainable solution for glass would be the reuse of glass waste in the production of concrete. Glass residues when suitably crushed and sieved, to assume appropriate granulometry, may exhibit characteristics similar to natural aggregates. The use of glass waste when used in concrete manufacturing reduces production costs. The main objective of the research was to replace, as much as possible, in percentage, the quantity of sand and gravel aggregates by glass waste with the same granulometry, as a way to reduce costs, reduce the use of raw materials and reduce the quantity of wastes that were inadequately disposed of in landfills. Samples of glass waste were collected in the construction industry itself, in works and glassware companies that work with cutting and delivery of the product. Comparisons were made between concretes produced with natural and concrete aggregates produced with the substitution of 20%, 30%, 40% and 50% of the fine aggregate, all of which glass was used as a substitute. The comparative analyzes were the mechanical properties of compression strength and diametral compression traction at 7, 14, 21, 28 and 90 days.

Waste reuse is considered an excellent alternative for sustainable development. For the World Commission on Environment and Development in Our Common Future, sustainability is "one that meets the needs of the present without compromising the ability of future generations to meet their needs." One way to provide a sustainable solution for glass would be the reuse of glass waste in the production of concrete. Glass residues when suitably crushed and sieved, to assume appropriate granulometry, may exhibit characteristics similar to natural aggregates. The use of glass waste when used in concrete manufacturing reduces production costs. The main objective of the research was to replace, as much as possible, in percentage, the quantity of sand and gravel aggregates by glass waste with the same granulometry, as a way to reduce costs, reduce the use of raw materials and reduce the quantity of wastes that were inadequately disposed of in landfills. Samples of glass waste were collected in the construction industry itself, in works and glassware companies that work with cutting and delivery of the product. Comparisons were made between concretes produced with natural and concrete aggregates produced with the substitution of 20%, 30%, 40% and 50% of the fine aggregate, all of which glass was used as a substitute. The comparative analyzes were the mechanical properties of compression strength and diametral compression traction at 7, 14, 21, 28 and 90 days.

Physico-chemical characteristics of waste, particularly fine fraction (FF), from an old crystal glass waste dump in Sweden were studied to assess recycling or disposal alternatives. Hand-sorting of the waste indicated glass content of 44.1% while sieving established the FF as a more soil-like mix of glass and other materials constituting 33.3% of all excavated waste. The FF was around neutral pH with 24.4% moisture content, low values of Total Dissolved Solids, Dissolved Organic Carbon and fluorides, but hazardous concentrations of As, Cd, Pb and Zn according to the Swedish Environmental Protection Agency guidelines. While the FF leached metals in low concentrations at neutral pH, it leached considerably during digestion with nitric acid, implying leaching risks at low pH. Thus, the waste requires safe storage in hazardous waste class ‘bank account’ storage cells to avoid environmental contamination as metal recovery and other recycling strategies for the glass waste are being developed. The study could fill the information gap regarding preservation of potential resources in the on-going, fast-paced excavation and re-landfilling of heavy metal contaminated materials in the region.

The design of bioactive glass materials which is strictly related to glass technology is one of the main achievements in glass production. The attention towards the preparation of glass and glass-ceramics materials for applications in dentistry has increased. The CaO-SiO2-CaF2-P2O5-Al2O3 glass system has been studied by other researchers where the material produced has high mechanical strength as compared to other bioactive glass and glass-ceramics. Although this glass and glass-ceramics are well established for dental application, its effect on using waste materials such as clam shell (CS) and soda lime silica (SLS) glass for use in the dental field has not been extensively studied. Thus, in this study, Alumino-Silicate-Fluoride (ASF) glass and glass- ceramics were fabricated and synthesised using CS and SLS glass as a source of CaO and SiO2, respectively. A series of ASF glass samples were prepared by using the conventional melt-quench technique. The thermal, chemical, physical, structural and mechanical properties of precursor glass and glass-ceramics were measured by differential scanning calorimetry (DSC), x-ray fluorescence (XRF), energy-dispersive x-ray (EDX), average density, molar volume, linear shrinkage, x-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), Fourier transform infrared (FTIR) and Vickers hardness (Hv) measurement. The density of the un-sintered pellets was found to increase with increasing of CS powder in the glass samples. Moreover, the density and linear shrinkage of glass-ceramic samples also increased with the increasing of sintering temperature. However, these measurements have slightly decreased at 1100 ℃ and 1200 ℃. The introduction of CaO-SiO2-CaF2-P2O5-Al2O3 containing materials, as well as the specific regime of sintering of the glass, gave glass-ceramics materials with crystalline phases of the hexagonal Ca5(PO4)3F (fluorapatite), orthorhombic Al5SiO9.5 (mullite) and anorthic (Ca(Al2Si2O8)) (anorthite) cry

Risks associated with metal contaminated sites are tightly linked to material leachability and contaminant mobility. In this study, metal solubility and transport were characterized within a glass waste landfill through i) lysimeter-collection of pore water and standardized batch leaching tests, ii) soil profiles extending from the landfill surface, through unsaturated soil underneath, and into the groundwater zone, and iii) groundwater samples upstream, at, and downstream of the landfill. The soil analyzes targeted both pseudo-total and geochemically active concentrations of contaminant metals (As, Cd, Pb, Sb) and basic soil geochemistry (pH, org. C, Fe,Mn). Water samples were analyzed for dissolved, colloid-bound and particulate metals, and speciation modelling of the aqueous phase was conducted. The results revealed a highly contaminated system, with mean metal concentrationsin the waste zone between 90 and 250 times the regional background levels. Despite severe contamination of the waste zone and high geochemically active fractions (80–100%) of all contaminant metals as well as elevated concentrations in landfill pore water, the concentrations of Cd and Pb decrease abruptly at the transition between landfill and underlying natural soil and no indication of groundwater contamination was found. The efficient cation retention is likely due to the high pH. However, the sorption of As and Sb is weaker at such high pH,which explains their higher mobility from the pore water zone into groundwater. The field soil:solution for Pb, ranging from 140 to 2,900,000 l kg−1), despite little variability in basic geochemical variables, which we suggest is due to waste material heterogeneity.

Physico-chemical characteristics of waste, particularly fine fraction (FF), from an old crystal glass waste dump in Sweden were studied to assess recycling or disposal alternatives. Hand-sorting of the waste indicated glass content of 44.1% while sieving established the FF as a more soil-like mix of glass and other materials constituting 33.3% of all excavated waste. The FF was around neutral pH with 24.4% moisture content, low values of Total Dissolved Solids, Dissolved Organic Carbon and fluorides, but hazardous concentrations of As, Cd, Pb and Zn according to the Swedish Environmental Protection Agency guidelines. While the FF leached metals in low concentrations at neutral pH, it leached considerably during digestion with nitric acid, implying leaching risks at low pH. Thus, the waste requires safe storage in hazardous waste class ‘bank account’ storage cells to avoid environmental contamination as metal recovery and other recycling strategies for the glass waste are being developed. The study could fill the information gap regarding preservation of potential resources in the on-going, fast-paced excavation and re-landfilling of heavy metal contaminated materials in the region.

Waste reuse is considered an excellent alternative for sustainable development. For the World Commission on Environment and Development in Our Common Future, sustainability is "one that meets the needs of the present without compromising the ability of future generations to meet their needs." One way to provide a sustainable solution for glass would be the reuse of glass waste in the production of concrete. Glass residues when suitably crushed and sieved, to assume appropriate granulometry, may exhibit characteristics similar to natural aggregates. The use of glass waste when used in concrete manufacturing reduces production costs. The main objective of the research was to replace, as much as possible, in percentage, the quantity of sand and gravel aggregates by glass waste with the same granulometry, as a way to reduce costs, reduce the use of raw materials and reduce the quantity of wastes that were inadequately disposed of in landfills. Samples of glass waste were collected in the construction industry itself, in works and glassware companies that work with cutting and delivery of the product. Comparisons were made between concretes produced with natural and concrete aggregates produced with the substitution of 20%, 30%, 40% and 50% of the fine aggregate, all of which glass was used as a substitute. The comparative analyzes were the mechanical properties of compression strength and diametral compression traction at 7, 14, 21, 28 and 90 days.

Waste reuse is considered an excellent alternative for sustainable development. For the World Commission on Environment and Development in Our Common Future, sustainability is "one that meets the needs of the present without compromising the ability of future generations to meet their needs." One way to provide a sustainable solution for glass would be the reuse of glass waste in the production of concrete. Glass residues when suitably crushed and sieved, to assume appropriate granulometry, may exhibit characteristics similar to natural aggregates. The use of glass waste when used in concrete manufacturing reduces production costs. The main objective of the research was to replace, as much as possible, in percentage, the quantity of sand and gravel aggregates by glass waste with the same granulometry, as a way to reduce costs, reduce the use of raw materials and reduce the quantity of wastes that were inadequately disposed of in landfills. Samples of glass waste were collected in the construction industry itself, in works and glassware companies that work with cutting and delivery of the product. Comparisons were made between concretes produced with natural and concrete aggregates produced with the substitution of 20%, 30%, 40% and 50% of the fine aggregate, all of which glass was used as a substitute. The comparative analyzes were the mechanical properties of compression strength and diametral compression traction at 7, 14, 21, 28 and 90 days.

Physico-chemical characteristics of waste, particularly fine fraction (FF), from an old crystal glass waste dump in Sweden were studied to assess recycling or disposal alternatives. Hand-sorting of the waste indicated glass content of 44.1% while sieving established the FF as a more soil-like mix of glass and other materials constituting 33.3% of all excavated waste. The FF was around neutral pH with 24.4% moisture content, low values of Total Dissolved Solids, Dissolved Organic Carbon and fluorides, but hazardous concentrations of As, Cd, Pb and Zn according to the Swedish Environmental Protection Agency guidelines. While the FF leached metals in low concentrations at neutral pH, it leached considerably during digestion with nitric acid, implying leaching risks at low pH. Thus, the waste requires safe storage in hazardous waste class ‘bank account’ storage cells to avoid environmental contamination as metal recovery and other recycling strategies for the glass waste are being developed. The study could fill the information gap regarding preservation of potential resources in the on-going, fast-paced excavation and re-landfilling of heavy metal contaminated materials in the region.

Physico-chemical characteristics of waste, particularly fine fraction (FF), from an old crystal glass waste dump in Sweden were studied to assess recycling or disposal alternatives. Hand-sorting of the waste indicated glass content of 44.1% while sieving established the FF as a more soil-like mix of glass and other materials constituting 33.3% of all excavated waste. The FF was around neutral pH with 24.4% moisture content, low values of Total Dissolved Solids, Dissolved Organic Carbon and fluorides, but hazardous concentrations of As, Cd, Pb and Zn according to the Swedish Environmental Protection Agency guidelines. While the FF leached metals in low concentrations at neutral pH, it leached considerably during digestion with nitric acid, implying leaching risks at low pH. Thus, the waste requires safe storage in hazardous waste class ‘bank account’ storage cells to avoid environmental contamination as metal recovery and other recycling strategies for the glass waste are being developed. The study could fill the information gap regarding preservation of potential resources in the on-going, fast-paced excavation and re-landfilling of heavy metal contaminated materials in the region.

Risks associated with metal contaminated sites are tightly linked to material leachability and contaminant mobility. In this study, metal solubility and transport were characterized within a glass waste landfill through i) lysimeter-collection of pore water and standardized batch leaching tests, ii) soil profiles extending from the landfill surface, through unsaturated soil underneath, and into the groundwater zone, and iii) groundwater samples upstream, at, and downstream of the landfill. The soil analyzes targeted both pseudo-total and geochemically active concentrations of contaminant metals (As, Cd, Pb, Sb) and basic soil geochemistry (pH, org. C, Fe,Mn). Water samples were analyzed for dissolved, colloid-bound and particulate metals, and speciation modelling of the aqueous phase was conducted. The results revealed a highly contaminated system, with mean metal concentrationsin the waste zone between 90 and 250 times the regional background levels. Despite severe contamination of the waste zone and high geochemically active fractions (80–100%) of all contaminant metals as well as elevated concentrations in landfill pore water, the concentrations of Cd and Pb decrease abruptly at the transition between landfill and underlying natural soil and no indication of groundwater contamination was found. The efficient cation retention is likely due to the high pH. However, the sorption of As and Sb is weaker at such high pH,which explains their higher mobility from the pore water zone into groundwater. The field soil:solution for Pb, ranging from 140 to 2,900,000 l kg−1), despite little variability in basic geochemical variables, which we suggest is due to waste material heterogeneity.

The design of bioactive glass materials which is strictly related to glass technology is one of the main achievements in glass production. The attention towards the preparation of glass and glass-ceramics materials for applications in dentistry has increased. The CaO-SiO2-CaF2-P2O5-Al2O3 glass system has been studied by other researchers where the material produced has high mechanical strength as compared to other bioactive glass and glass-ceramics. Although this glass and glass-ceramics are well established for dental application, its effect on using waste materials such as clam shell (CS) and soda lime silica (SLS) glass for use in the dental field has not been extensively studied. Thus, in this study, Alumino-Silicate-Fluoride (ASF) glass and glass- ceramics were fabricated and synthesised using CS and SLS glass as a source of CaO and SiO2, respectively. A series of ASF glass samples were prepared by using the conventional melt-quench technique. The thermal, chemical, physical, structural and mechanical properties of precursor glass and glass-ceramics were measured by differential scanning calorimetry (DSC), x-ray fluorescence (XRF), energy-dispersive x-ray (EDX), average density, molar volume, linear shrinkage, x-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), Fourier transform infrared (FTIR) and Vickers hardness (Hv) measurement. The density of the un-sintered pellets was found to increase with increasing of CS powder in the glass samples. Moreover, the density and linear shrinkage of glass-ceramic samples also increased with the increasing of sintering temperature. However, these measurements have slightly decreased at 1100 ℃ and 1200 ℃. The introduction of CaO-SiO2-CaF2-P2O5-Al2O3 containing materials, as well as the specific regime of sintering of the glass, gave glass-ceramics materials with crystalline phases of the hexagonal Ca5(PO4)3F (fluorapatite), orthorhombic Al5SiO9.5 (mullite) and anorthic (Ca(Al2Si2O8)) (anorthite) cry

Physico-chemical characteristics of waste, particularly fine fraction (FF), from an old crystal glass waste dump in Sweden were studied to assess recycling or disposal alternatives. Hand-sorting of the waste indicated glass content of 44.1% while sieving established the FF as a more soil-like mix of glass and other materials constituting 33.3% of all excavated waste. The FF was around neutral pH with 24.4% moisture content, low values of Total Dissolved Solids, Dissolved Organic Carbon and fluorides, but hazardous concentrations of As, Cd, Pb and Zn according to the Swedish Environmental Protection Agency guidelines. While the FF leached metals in low concentrations at neutral pH, it leached considerably during digestion with nitric acid, implying leaching risks at low pH. Thus, the waste requires safe storage in hazardous waste class ‘bank account’ storage cells to avoid environmental contamination as metal recovery and other recycling strategies for the glass waste are being developed. The study could fill the information gap regarding preservation of potential resources in the on-going, fast-paced excavation and re-landfilling of heavy metal contaminated materials in the region.

Risks associated with metal contaminated sites are tightly linked to material leachability and contaminant mobility. In this study, metal solubility and transport were characterized within a glass waste landfill through i) lysimeter-collection of pore water and standardized batch leaching tests, ii) soil profiles extending from the landfill surface, through unsaturated soil underneath, and into the groundwater zone, and iii) groundwater samples upstream, at, and downstream of the landfill. The soil analyzes targeted both pseudo-total and geochemically active concentrations of contaminant metals (As, Cd, Pb, Sb) and basic soil geochemistry (pH, org. C, Fe,Mn). Water samples were analyzed for dissolved, colloid-bound and particulate metals, and speciation modelling of the aqueous phase was conducted. The results revealed a highly contaminated system, with mean metal concentrationsin the waste zone between 90 and 250 times the regional background levels. Despite severe contamination of the waste zone and high geochemically active fractions (80–100%) of all contaminant metals as well as elevated concentrations in landfill pore water, the concentrations of Cd and Pb decrease abruptly at the transition between landfill and underlying natural soil and no indication of groundwater contamination was found. The efficient cation retention is likely due to the high pH. However, the sorption of As and Sb is weaker at such high pH,which explains their higher mobility from the pore water zone into groundwater. The field soil:solution for Pb, ranging from 140 to 2,900,000 l kg−1), despite little variability in basic geochemical variables, which we suggest is due to waste material heterogeneity.

An old glass dumpsite in southern Sweden was mapped and investigated to locate glass abundance zones (“hotspots”) and understand physicochemical parametres of the waste. Global Positioning System (GPS) was used for mapping the site while a geophysical method of Electrical Resistivity was used for detecting glass hotspots in the dump. Test pits were excavated and samples taken, after which hand sorting, sieving and X-Ray Fluorescence (XRF) scanning of the waste were used for physicochemical properties. Geophysical mapping was found to be a feasible nondestructive tool in locating glass hotspots. In terms of composition, glass was found to be the most abundant fraction at 90% average from all 4 sampling points. From particle size distribution, particles > 11.3 mm were more abundant (75% average) than particles < 11.3 mm. XRF scanning yielded As, Cd and Pb concentrations of 3,700 mg/kg, 500 mg/kg and 5,300 mg/kg, respectively. In conclusion, it is possible to locate glass hotspots and excavate them carefully in readiness for metal extraction while avoiding the need for complicated sorting post-excavation.

Landfills and dumpsites have been the ultimate end of life sinks for various materials and products. As such, they are considered rich stocks of secondary raw materials for the circular economy. However, most of them are non-sanitary as they lack protective measures against environmental contamination. Over the years, the need to exploit the resource potential of landfills as well as to mitigate their contamination problems, among other factors, has led to the concept of landfill mining, resulting in a number of mainly pilot scale mining of landfills and dumps globally. In southeastern Sweden for instance, where there are over forty old, contaminated glass dumps, a number of remedial dumpsite excavations have been going on, with eventual landfilling of excavated materials in sanitary landfills. Hence, based on the Swedish situation, this study presents three scenarios about: contaminated materials in non-sanitary dumps as they currently stand; ongoing material excavations with subsequent landfilling; and material excavations coupled with materials recovery towards reduced landfilling. The third scenario is presented as more suitable from the circular economy perspective. The scenario is thus discussed in terms of technological implications of the process from identification of concealed valuable materials in dumps to their excavation, sorting, temporal storage, valorization and eventual resource recovery. In addition, legal implications as well as potential social, economic and environmental barriers against the scenario’s implementation are discussed. Finally, the study provides recommendations that would be useful in decision making surrounding the management of contaminated and non-sanitary dumpsites.

An old glass dumpsite in southern Sweden was mapped and investigated to locate glass abundance zones (“hotspots”) and understand physicochemical parametres of the waste. Global Positioning System (GPS) was used for mapping the site while a geophysical method of Electrical Resistivity was used for detecting glass hotspots in the dump. Test pits were excavated and samples taken, after which hand sorting, sieving and X-Ray Fluorescence (XRF) scanning of the waste were used for physicochemical properties. Geophysical mapping was found to be a feasible nondestructive tool in locating glass hotspots. In terms of composition, glass was found to be the most abundant fraction at 90% average from all 4 sampling points. From particle size distribution, particles > 11.3 mm were more abundant (75% average) than particles < 11.3 mm. XRF scanning yielded As, Cd and Pb concentrations of 3,700 mg/kg, 500 mg/kg and 5,300 mg/kg, respectively. In conclusion, it is possible to locate glass hotspots and excavate them carefully in readiness for metal extraction while avoiding the need for complicated sorting post-excavation.

Although in theory glass can be endlessly remelted without loss in quality, in practice only a small percentage gets recycled, mainly by the packaging industry. Most of the discarded glass fails to pass the high quality standards of the prevailing glass industry -due to coatings, adhesives, other contaminants or incompatibility of the recipe- and ends up in the landfill. However, employing discarded glass in cast components for building applications can be a way to reintroduce this waste to the supply chain. Such components can tolerate a higher percentage of inclusions, without necessarily compromising their mechanical or aesthetical properties. This paper explores the potential but also the limitations of recycling glass in order to obtain load-bearing components. First, an overview is provided regarding which types of glass reach the recycling plants and the which not, arguing on the reasons behind this selection. Afterwards, a series of experiments is presented, exploring the possibilities of recycling everyday glass waste, from beer bottles and Pyrex® trays to mobile phone screens. Each type of glass waste is initially cast separately to define its flow capability and risk of crystallization. The above information is linked to the X-ray fluorescence (XRF) analyses of the samples prior to recycling. Then, the possibility to mix different glass recipes without fracturing is evaluated. The results point out the types of glass with potential in structural applications, and the overall feasibility of the concept., Applied Mechanics, Structural Design & Mechanics, OLD Structural Design

Although in theory glass can be endlessly re-melted without loss in quality, in practice only a small percentage gets recycled, mainly by the packaging industry. Most of the discarded glass fails to pass the high quality standards of the prevailing glass industry – due to coatings, adhesives, other contaminants or incompatibility of the recipe – and ends up in landfill. However, using discarded glass in cast components for building applications can be a good way to reintroduce this waste to the supply chain. Such components can tolerate a higher percentage of inclusions, without necessarily compromising their mechanical or aesthetical properties. This paper explores the potential but also the limitations of recycling glass in order to obtain load-bearing components. First, an overview is provided regarding which types of glass reach the recycling plants and which not, arguing on the reasons behind this selection. Afterwards, a series of experiments is presented, exploring the possibilities of recycling everyday glass waste, from beer bottles and Pyrex trays to mobile phone screens. Each type of glass waste is cast at different temperatures and firing/cooling rates to define its flow capability and risk of crystallization. The above information is linked to the X-ray fluorescence (XRF) analyses of the samples prior to recycling. The results point out the types of glass with potential in structural applications, and the overall feasibility of the concept. This paper is an extension of previously reported work by Bristogianni et al. 2018., Applied Mechanics, Structural Design & Mechanics, OLD Structural Design

An old glass dumpsite in southern Sweden was mapped and investigated to locate glass abundance zones (“hotspots”) and understand physicochemical parametres of the waste. Global Positioning System (GPS) was used for mapping the site while a geophysical method of Electrical Resistivity was used for detecting glass hotspots in the dump. Test pits were excavated and samples taken, after which hand sorting, sieving and X-Ray Fluorescence (XRF) scanning of the waste were used for physicochemical properties. Geophysical mapping was found to be a feasible nondestructive tool in locating glass hotspots. In terms of composition, glass was found to be the most abundant fraction at 90% average from all 4 sampling points. From particle size distribution, particles > 11.3 mm were more abundant (75% average) than particles < 11.3 mm. XRF scanning yielded As, Cd and Pb concentrations of 3,700 mg/kg, 500 mg/kg and 5,300 mg/kg, respectively. In conclusion, it is possible to locate glass hotspots and excavate them carefully in readiness for metal extraction while avoiding the need for complicated sorting post-excavation.

An old glass dumpsite in southern Sweden was mapped and investigated to locate glass abundance zones (“hotspots”) and understand physicochemical parametres of the waste. Global Positioning System (GPS) was used for mapping the site while a geophysical method of Electrical Resistivity was used for detecting glass hotspots in the dump. Test pits were excavated and samples taken, after which hand sorting, sieving and X-Ray Fluorescence (XRF) scanning of the waste were used for physicochemical properties. Geophysical mapping was found to be a feasible nondestructive tool in locating glass hotspots. In terms of composition, glass was found to be the most abundant fraction at 90% average from all 4 sampling points. From particle size distribution, particles > 11.3 mm were more abundant (75% average) than particles < 11.3 mm. XRF scanning yielded As, Cd and Pb concentrations of 3,700 mg/kg, 500 mg/kg and 5,300 mg/kg, respectively. In conclusion, it is possible to locate glass hotspots and excavate them carefully in readiness for metal extraction while avoiding the need for complicated sorting post-excavation.

An old glass dumpsite in southern Sweden was mapped and investigated to locate glass abundance zones (“hotspots”) and understand physicochemical parametres of the waste. Global Positioning System (GPS) was used for mapping the site while a geophysical method of Electrical Resistivity was used for detecting glass hotspots in the dump. Test pits were excavated and samples taken, after which hand sorting, sieving and X-Ray Fluorescence (XRF) scanning of the waste were used for physicochemical properties. Geophysical mapping was found to be a feasible nondestructive tool in locating glass hotspots. In terms of composition, glass was found to be the most abundant fraction at 90% average from all 4 sampling points. From particle size distribution, particles > 11.3 mm were more abundant (75% average) than particles < 11.3 mm. XRF scanning yielded As, Cd and Pb concentrations of 3,700 mg/kg, 500 mg/kg and 5,300 mg/kg, respectively. In conclusion, it is possible to locate glass hotspots and excavate them carefully in readiness for metal extraction while avoiding the need for complicated sorting post-excavation.

Landfills and dumpsites have been the ultimate end of life sinks for various materials and products. As such, they are considered rich stocks of secondary raw materials for the circular economy. However, most of them are non-sanitary as they lack protective measures against environmental contamination. Over the years, the need to exploit the resource potential of landfills as well as to mitigate their contamination problems, among other factors, has led to the concept of landfill mining, resulting in a number of mainly pilot scale mining of landfills and dumps globally. In southeastern Sweden for instance, where there are over forty old, contaminated glass dumps, a number of remedial dumpsite excavations have been going on, with eventual landfilling of excavated materials in sanitary landfills. Hence, based on the Swedish situation, this study presents three scenarios about: contaminated materials in non-sanitary dumps as they currently stand; ongoing material excavations with subsequent landfilling; and material excavations coupled with materials recovery towards reduced landfilling. The third scenario is presented as more suitable from the circular economy perspective. The scenario is thus discussed in terms of technological implications of the process from identification of concealed valuable materials in dumps to their excavation, sorting, temporal storage, valorization and eventual resource recovery. In addition, legal implications as well as potential social, economic and environmental barriers against the scenario’s implementation are discussed. Finally, the study provides recommendations that would be useful in decision making surrounding the management of contaminated and non-sanitary dumpsites.

An old glass dumpsite in southern Sweden was mapped and investigated to locate glass abundance zones (“hotspots”) and understand physicochemical parametres of the waste. Global Positioning System (GPS) was used for mapping the site while a geophysical method of Electrical Resistivity was used for detecting glass hotspots in the dump. Test pits were excavated and samples taken, after which hand sorting, sieving and X-Ray Fluorescence (XRF) scanning of the waste were used for physicochemical properties. Geophysical mapping was found to be a feasible nondestructive tool in locating glass hotspots. In terms of composition, glass was found to be the most abundant fraction at 90% average from all 4 sampling points. From particle size distribution, particles > 11.3 mm were more abundant (75% average) than particles < 11.3 mm. XRF scanning yielded As, Cd and Pb concentrations of 3,700 mg/kg, 500 mg/kg and 5,300 mg/kg, respectively. In conclusion, it is possible to locate glass hotspots and excavate them carefully in readiness for metal extraction while avoiding the need for complicated sorting post-excavation.

Although in theory glass can be endlessly re-melted without loss in quality, in practice only a small percentage gets recycled, mainly by the packaging industry. Most of the discarded glass fails to pass the high quality standards of the prevailing glass industry – due to coatings, adhesives, other contaminants or incompatibility of the recipe – and ends up in landfill. However, using discarded glass in cast components for building applications can be a good way to reintroduce this waste to the supply chain. Such components can tolerate a higher percentage of inclusions, without necessarily compromising their mechanical or aesthetical properties. This paper explores the potential but also the limitations of recycling glass in order to obtain load-bearing components. First, an overview is provided regarding which types of glass reach the recycling plants and which not, arguing on the reasons behind this selection. Afterwards, a series of experiments is presented, exploring the possibilities of recycling everyday glass waste, from beer bottles and Pyrex trays to mobile phone screens. Each type of glass waste is cast at different temperatures and firing/cooling rates to define its flow capability and risk of crystallization. The above information is linked to the X-ray fluorescence (XRF) analyses of the samples prior to recycling. The results point out the types of glass with potential in structural applications, and the overall feasibility of the concept. This paper is an extension of previously reported work by Bristogianni et al. 2018., Applied Mechanics, Structural Design & Mechanics, OLD Structural Design

Although in theory glass can be endlessly remelted without loss in quality, in practice only a small percentage gets recycled, mainly by the packaging industry. Most of the discarded glass fails to pass the high quality standards of the prevailing glass industry -due to coatings, adhesives, other contaminants or incompatibility of the recipe- and ends up in the landfill. However, employing discarded glass in cast components for building applications can be a way to reintroduce this waste to the supply chain. Such components can tolerate a higher percentage of inclusions, without necessarily compromising their mechanical or aesthetical properties. This paper explores the potential but also the limitations of recycling glass in order to obtain load-bearing components. First, an overview is provided regarding which types of glass reach the recycling plants and the which not, arguing on the reasons behind this selection. Afterwards, a series of experiments is presented, exploring the possibilities of recycling everyday glass waste, from beer bottles and Pyrex® trays to mobile phone screens. Each type of glass waste is initially cast separately to define its flow capability and risk of crystallization. The above information is linked to the X-ray fluorescence (XRF) analyses of the samples prior to recycling. Then, the possibility to mix different glass recipes without fracturing is evaluated. The results point out the types of glass with potential in structural applications, and the overall feasibility of the concept., Applied Mechanics, Structural Design & Mechanics, OLD Structural Design

An old glass dumpsite in southern Sweden was mapped and investigated to locate glass abundance zones (“hotspots”) and understand physicochemical parametres of the waste. Global Positioning System (GPS) was used for mapping the site while a geophysical method of Electrical Resistivity was used for detecting glass hotspots in the dump. Test pits were excavated and samples taken, after which hand sorting, sieving and X-Ray Fluorescence (XRF) scanning of the waste were used for physicochemical properties. Geophysical mapping was found to be a feasible nondestructive tool in locating glass hotspots. In terms of composition, glass was found to be the most abundant fraction at 90% average from all 4 sampling points. From particle size distribution, particles > 11.3 mm were more abundant (75% average) than particles < 11.3 mm. XRF scanning yielded As, Cd and Pb concentrations of 3,700 mg/kg, 500 mg/kg and 5,300 mg/kg, respectively. In conclusion, it is possible to locate glass hotspots and excavate them carefully in readiness for metal extraction while avoiding the need for complicated sorting post-excavation.

Landfills and dumpsites have been the ultimate end of life sinks for various materials and products. As such, they are considered rich stocks of secondary raw materials for the circular economy. However, most of them are non-sanitary as they lack protective measures against environmental contamination. Over the years, the need to exploit the resource potential of landfills as well as to mitigate their contamination problems, among other factors, has led to the concept of landfill mining, resulting in a number of mainly pilot scale mining of landfills and dumps globally. In southeastern Sweden for instance, where there are over forty old, contaminated glass dumps, a number of remedial dumpsite excavations have been going on, with eventual landfilling of excavated materials in sanitary landfills. Hence, based on the Swedish situation, this study presents three scenarios about: contaminated materials in non-sanitary dumps as they currently stand; ongoing material excavations with subsequent landfilling; and material excavations coupled with materials recovery towards reduced landfilling. The third scenario is presented as more suitable from the circular economy perspective. The scenario is thus discussed in terms of technological implications of the process from identification of concealed valuable materials in dumps to their excavation, sorting, temporal storage, valorization and eventual resource recovery. In addition, legal implications as well as potential social, economic and environmental barriers against the scenario’s implementation are discussed. Finally, the study provides recommendations that would be useful in decision making surrounding the management of contaminated and non-sanitary dumpsites.

An old glass dumpsite in southern Sweden was mapped and investigated to locate glass abundance zones (“hotspots”) and understand physicochemical parametres of the waste. Global Positioning System (GPS) was used for mapping the site while a geophysical method of Electrical Resistivity was used for detecting glass hotspots in the dump. Test pits were excavated and samples taken, after which hand sorting, sieving and X-Ray Fluorescence (XRF) scanning of the waste were used for physicochemical properties. Geophysical mapping was found to be a feasible nondestructive tool in locating glass hotspots. In terms of composition, glass was found to be the most abundant fraction at 90% average from all 4 sampling points. From particle size distribution, particles > 11.3 mm were more abundant (75% average) than particles < 11.3 mm. XRF scanning yielded As, Cd and Pb concentrations of 3,700 mg/kg, 500 mg/kg and 5,300 mg/kg, respectively. In conclusion, it is possible to locate glass hotspots and excavate them carefully in readiness for metal extraction while avoiding the need for complicated sorting post-excavation.

An old glass dumpsite in southern Sweden was mapped and investigated to locate glass abundance zones (“hotspots”) and understand physicochemical parametres of the waste. Global Positioning System (GPS) was used for mapping the site while a geophysical method of Electrical Resistivity was used for detecting glass hotspots in the dump. Test pits were excavated and samples taken, after which hand sorting, sieving and X-Ray Fluorescence (XRF) scanning of the waste were used for physicochemical properties. Geophysical mapping was found to be a feasible nondestructive tool in locating glass hotspots. In terms of composition, glass was found to be the most abundant fraction at 90% average from all 4 sampling points. From particle size distribution, particles > 11.3 mm were more abundant (75% average) than particles < 11.3 mm. XRF scanning yielded As, Cd and Pb concentrations of 3,700 mg/kg, 500 mg/kg and 5,300 mg/kg, respectively. In conclusion, it is possible to locate glass hotspots and excavate them carefully in readiness for metal extraction while avoiding the need for complicated sorting post-excavation.

Landfills and dumpsites have been the ultimate end of life sinks for various materials and products. As such, they are considered rich stocks of secondary raw materials for the circular economy. However, most of them are non-sanitary as they lack protective measures against environmental contamination. Over the years, the need to exploit the resource potential of landfills as well as to mitigate their contamination problems, among other factors, has led to the concept of landfill mining, resulting in a number of mainly pilot scale mining of landfills and dumps globally. In southeastern Sweden for instance, where there are over forty old, contaminated glass dumps, a number of remedial dumpsite excavations have been going on, with eventual landfilling of excavated materials in sanitary landfills. Hence, based on the Swedish situation, this study presents three scenarios about: contaminated materials in non-sanitary dumps as they currently stand; ongoing material excavations with subsequent landfilling; and material excavations coupled with materials recovery towards reduced landfilling. The third scenario is presented as more suitable from the circular economy perspective. The scenario is thus discussed in terms of technological implications of the process from identification of concealed valuable materials in dumps to their excavation, sorting, temporal storage, valorization and eventual resource recovery. In addition, legal implications as well as potential social, economic and environmental barriers against the scenario’s implementation are discussed. Finally, the study provides recommendations that would be useful in decision making surrounding the management of contaminated and non-sanitary dumpsites.

Landfills and dumpsites have been the ultimate end of life sinks for various materials and products. As such, they are considered rich stocks of secondary raw materials for the circular economy. However, most of them are non-sanitary as they lack protective measures against environmental contamination. Over the years, the need to exploit the resource potential of landfills as well as to mitigate their contamination problems, among other factors, has led to the concept of landfill mining, resulting in a number of mainly pilot scale mining of landfills and dumps globally. In southeastern Sweden for instance, where there are over forty old, contaminated glass dumps, a number of remedial dumpsite excavations have been going on, with eventual landfilling of excavated materials in sanitary landfills. Hence, based on the Swedish situation, this study presents three scenarios about: contaminated materials in non-sanitary dumps as they currently stand; ongoing material excavations with subsequent landfilling; and material excavations coupled with materials recovery towards reduced landfilling. The third scenario is presented as more suitable from the circular economy perspective. The scenario is thus discussed in terms of technological implications of the process from identification of concealed valuable materials in dumps to their excavation, sorting, temporal storage, valorization and eventual resource recovery. In addition, legal implications as well as potential social, economic and environmental barriers against the scenario’s implementation are discussed. Finally, the study provides recommendations that would be useful in decision making surrounding the management of contaminated and non-sanitary dumpsites.