Differences during the last 15years in materials' composition in Municipal Solid Waste Incineration (MSWI) regarding bottom ash (BA) were assessed as a function of particle size (>16, 8–16, 4–8, 2–4, ...1–2 and 0–1mm). After sieving, fractions >2mm were carefully washed in order to separate fine particles adhering to bigger particles. The characterization took into account five types of materials: glass (primary and secondary), ceramics (natural and synthetic), non-ferrous metals, ferrous metals and unburned organic matter. The evaluation was performed through a visual (>2mm) and chemical (0–2mm) classification. Results showed that total weight of glass in the particles over 16mm has decreased with respect to 1999. Moreover, the content of glass (primary and secondary) in BA was estimated to be 60.8wt%, with 26.4wt% corresponding to primary glass in >2mm size fractions. Unlike 1999, in which glass was the predominant material, ceramics are currently the major phase in bottom ash (BA) coarse fractions. As for the metals, respect to 1999, results showed a slight increase in all size fractions. The greatest content (>22wt%) of ferromagnetic was observed for the 2–4mm size fraction while the non-ferrous type was almost non-existent in particles over 16mm, remaining below 10wt% for the rest fractions. In the finest fractions (<2mm), about 60 to 95% of non-ferrous metals corresponded to metallic aluminium. The results from the chemical characterization also indicated that the finest fractions contributed significantly to the total heavy metals content, especially for Pb, Zn, Cu, Mn and Ti.
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•The content of glass in particles >16mm has decreased in weathered bottom ash (WBA).•Entire glass bottles have been easily recycled and extensively substituted by plastic.•There's still a significant amount of glass that's left unrecycled: 60.8%.•Ceramics are currently the major phase in WBA coarse fractions.•The finest fractions are the major contributors to the heavy metals content.
•Glasses were prepared using tungsten mine tailings.•The wastes tested were suitable for the manufacture of commercial glass.•The obtained glasses retains the potentially toxic elements.
Glasses from ...different types of tungsten mine tailings were obtained and studied to determine their ability to be used as raw materials of commercial glass. Tailings of granitic composition from Barruecopardo, of calc-silicate wastes from Morille, and of schists and quartz from Panasqueira, were used as raw materials. The addition of CaCO3 and NaCO3 was necessary for the manufacture of the glass. Samples were characterised by XRF, XRD, HSM and DTA-TG. Furthermore, the expansion coefficient, Vickers microhardness and leaching properties were measured. The results show that all the tungsten mine tailings used were suitable for the manufacture of commercial glass, with the addition of calcium and soda. The calc-silicate tailing needs less additive content to produce a glass. Also, they present lower workability temperatures and higher durability. Glasses obtained from all the tested tailings retain the potentially toxic elements in their structure and prevents the environmental pollution.
•The analysis of the lithic industry from Cova del Vidre defines its evolutionary changes between 10.800-5.000 cal. BC.•A new C14 date is presented in the Sauveterrian phase allowing it to model and ...fix its lithics to the chronological sequence.•The lithic production for each phase is in line with the traits of Western Mediterranean except for Late Mesolithic.
Cova del Vidre (Roquetes, Tarragona, Spain), strategically located in El Port massif, a high-altitude mountain range contrasting with the lower course of the Ebro River, has an interrupted sequence of occupations from the beginning of the Holocene until the establishment of the first Neolithic groups (c. 10,800–5000 cal. BC). It is currently the site with the most complete sequence detected in the lower Ebro valley.
The comprehensive analysis of the knapped lithic industry from the four phases identified during excavations in the 1950s–1960s and 1992 (Microlaminar Epipaleolithic, Sauveterrian, Late Mesolithic, and Early Cardial Neolithic) reveals significant evolution in the management and exploitation of chipped stone raw materials, their technology, and the formalization of tools in the four occupation phases. Furthermore, the chronological determination of the Sauveterrian phase by radiocarbon dating (14C) allows us to integrate the largest assemblage in the sequence within the regional productive dynamics. It also enables us to establish the temporal sequence of the detected occupations together with the previously published radiocarbon dates.
Concrete is a material which is widely used in architecture, not only for structural purposes but also for architectural elements for its versatility and excellent performance. However, the ...manufacturing of this material as a mixture of water, cement, and fine and coarse aggregate comes with a high environmental cost, such as gas emissions, among other things. This is the reason why different alternatives are being proposed in order to replace coarse aggregates with other recycled materials, as it is one of the less sustainable components of the mixture in terms of extraction. One of these alternatives is recycled glass coming from drinking bottles, crushed into small grains and mixed in the same proportions as regular aggregates. This study proposes the mechanical characterization of a new architectural concrete mixture by using white Lafarge cement and glass-recycled aggregates; this proposed concrete is made especially for architectural elements like façade panels, rather than structural elements. The mechanical evaluation of this new material is done through a set of experimental tests under compression and also bending, comparing three different ratios of glass aggregate in the mixture.
Tailings from tungsten mining activities in the vicinity of Barruecopardo (Salamanca) represent high environmental pollution. In this paper we present a study of the use of these wastes as raw ...materials for the manufacture of glass. This procedure aims to contribute to environmental remediation of mining areas through vitrification, a process which offers an alternative for stabilization of hazardous wastes. In addition, the marketing of the obtained product would provide an additional income to the mining areas. The chemical composition of the tailings to be used as raw materials was determined by X-ray fluorescence and their mineralogy by X-ray diffraction. Wastes are of granitic composition enriched in potentially toxic elements. For this study, a representative sample of mining wastes of sandy grain size was used to make the glass. On the basis of its composition, glass was formulated by adding 29.28 mass% of CaCO3 and 14.03 mass% of Na2CO3 and a green glass was produced. Crystallisation temperatures, obtained by DTA, were 875 and 1022 °C and the melting temperature was 1175 °C. The transition temperature of glass was of 644 °C. The temperatures for the fixed viscosity points, and the working temperatures were obtained. A thermal treatment induced devitrification to produce a glass-ceramic made of nepheline and wollastonite. Leaching tests of the obtained glass confirm its capacity to retain potentially toxic elements.
Technology of production of polychrome lustre Molina, Gloria; Tite, Michael S.; Molera, Judit ...
Journal of the European Ceramic Society,
09/2014, Letnik:
34, Številka:
10
Journal Article, Publication
Recenzirano
Odprti dostop
Lustre is a decoration consisting of a few hundreds of nanometres thick surface layer of silver and copper metal nanoparticles incorporated into the glaze. Polychrome lustreware with several ...combinations of colours and shines was produced in Abbasid Iraq in the 9th century AD. Three colour combinations, black plus red, white-silvery plus red-coppery and yellow-golden plus red-coppery, have been studied, and the materials and methods of production determined. Two separated firings the first for the copper and the second for the silver lustre were performed. The black, white, yellow and green colours of the silver lustres are associated with the different sizes of the nanoparticles and to their distribution in the layer. Although the addition of lead and tin in the initial mixture is demonstrated, their incorporation in the glaze has been found to be the key factor in the production of the red-coppery and yellow-golden lustre.
A grisaille is a brown‐blackish paint applied onto the inner surface of stained glass to draw the contours and details of the figures and to produce the effect of shades and volumes. Grisailles were ...traditionally made of finely ground oxides of iron but also of copper, zinc, lead, or manganese mixed with a flux such as lead ground glass and a binder and fixed onto the flat glass by firing. The grisailles have typical layer thickness varying between 10 and 100 μm and are formed by a complex mixture of pigment particles, crystalline, and amorphous reaction compounds, aging, and weathering compounds. The high brilliance, collimation, energy selection, and monochromacity of the SR beam are ideal to obtain micro‐XRD patterns from thin cross sections of the grisailles. The analyses are complemented with SEM‐EDX and LA‐ICPMS. A selection of grisailles from several cathedrals and buildings in Spain, Avila, Burgos, Alcalá de Henares, and in particular from Segovia, dating from early 16th to the 20th century and belonging to several master glaziers are studied. Changes in the methods of production and materials in the different historical periods are obtained and also related to the conservation state of the materials.
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