Search results for "Smelting"
showing 9 items of 9 documents
The contamination legacy of a decommissioned iron smelter in the Italian Alps
2018
The economically important activity of metal processing can tend to contribute to the degradation of the environment. Smelting is an important source of contaminants, dispersing large quantities of potentially toxic elements (PTE) and coproducts into the environment. Soils in the vicinity of smelters frequently contain high concentrations of PTE. In terms of the quantities processed, the major PTE are iron (Fe), aluminium (Al), copper (Cu), lead (Pb), manganese (Mn), and zinc (Zn); of these Cu, Pb and Zn are, potentially, highly hazardous elements. The general problem addressed by this study is to determine if the PTE concentration in the soils of an area downwind from a decommissioned iron…
Soil decomposer animal community in heavy-metal contaminated coniferous forest with and without liming
2002
Abstract Responses of decomposer animals to heavy-metal contamination were studied near a Cu–Ni smelter in Finland. Samples were taken 0.5, 2 and 8 km from the smelter. In addition, plots fertilised with lime were sampled. Decomposer community in coniferous forest soil appeared to be quite resistant to heavy-metals. Only in the vicinity (0.5 km) of the smelter, were numbers of soil animals clearly decreased and their community structure strongly altered as compared to the control site (8 km). At the 2-km site, the community structure was only slightly changed. Most of the collembolan species were still found at the 0.5-km site. High metal sorption capacity of the humus, and heterogeneous di…
Analysis of Sagunto Ibero-Roman votive bronze statuettes by portable X-ray fluorescence
2019
Abstract The main objective of this work was the study of chemical composition of an important collection of Ibero-Roman votive bronze statuettes exposed in the Archaeological Museum of Sagunto (Spain). Precision and accuracy of the measurements were obtained developing a proper analytical method, also avoiding any possible damage to the studied objects using a portable energy dispersive X- ray fluorescence system. Principal Components Analysis (PCA) to discriminate between groups based on ratios Fe/Cu, Pb/Cu, Sn/Cu, Ag/Cu, Ni/Cu and Impurities/Cu were employed to observe differences between the used smelting, manufacturing processes and raw materials. The characterisation of bronze statuet…
Relationships between societies and their environment in the Sahel in southwestern Niger over the past four thousand years : a geoarchaeological appr…
2013
The Sahel, a zone between the Sahara Desert and the Sudan forests, is currently experiencing major environmental changes. Since the droughts in 1970s and 1980s, and with the high population growth rate, vegetation cover has deteriorated considerably, contributing to increased runoff and soil erosion. Starting from this observation, we undertook the study of past societies in the Niamey region, to assess their impact on the environment. The lack of archaeological data meant that it was necessary to identify key indicators of occupation during the Neolithic and the Iron Age. In addition to providing new evidence to date the Neolithic site of Kirkissoy, a sedimentary study was conducted on a p…
Classification et chronologie de bas fourneaux de réduction du fer à usage unique au sud-ouest du Niger
2016
In southwestern Niger, near Niamey, several thousand single-use bloomery furnaces have been mapped and identified. The archaeological study of approximately 30 furnaces and their slag reveals the existence of four methods for iron smelting: three types of pit furnace and one slag-tapping type. The slag pit furnaces are clearly differentiated by the form and volume of their pits. All slag-tapping furnaces drain off slag through small openings. The slag is tapped either vertically or laterally. According to radiocarbon dates, the smelting activity developed in the 2 nd century AD and intensified through to the 14 th century. It continued to evolve until the middle of the 20 th century. The lo…
Historical mining and smelting in the Vosges Mountains (France) recorded in two ombrotrophic peat bogs
2010
Two peat sequences were sampled in the vicinity of the main mining districts of the Vosges Mountains: Sainte-Marie-aux-Mines and Plancher-les-Mines. Lead isotopic compositions and excess lead fluxes were calculated for each of these radiocarbon-dated sequences. Geochemical records are in very good agreement with the mining history of the area, well known over the last millennium. Except for an anomaly corresponding to the Middle Bronze Age which has not yet been resolved, there is no clear geochemical evidence of local metal production in the Vosges before the 10th century as excess lead deposition archived between 500 BC and 500 AD is attributed to long-range transport of polluted particul…
Metallic lead recovery from lead-acid battery paste by urea acetate dissolution and cementation on iron
2009
Abstract A suitable hydrometallurgical and environmentally friendly process was studied to replace the currently used practices for recycling lead-acid batteries via smelting. Metallic lead was recovered by cementation from industrial lead sludge solutions of urea acetate (200 to 500 g/L) using different types of metallic iron substrates (nails, shaving or powder) as reducing agents. Under specific operating conditions, up to 99.7% of lead acid battery paste, mainly composed of PbSO4, PbO2 and PbO·PbSO4 species, was converted to metallic lead.. The conversion of the metallic lead and rate of the cementation reaction were strictly dependent on the type of iron substrate used as the reductant…
Environmental impact of early Basque mining and smelting recorded in a high ash minerogenic peat deposit.
2004
International audience; More than four metres of core, covering almost 5000 years of deposition, were collected in a high ash minerogenic peat deposit located in the High Aldudes valley (Basque country), an area well known for its mineral abundance, exploited from Roman Times at least.Although minerogenic peatlands are not generally considered as the best archives to reconstruct past atmospheric metal deposition history, lead isotopic geochemistry demonstrates the integrity of the Pb record at least within the three upper meters; that is to say over the last four millennia.Zn, Cd and Cumay have been widely redistributed either by biological cycling, advective groundwater movements, or diffu…
Lead in the Bones of Cows from a Medieval Pb-Ag Metallurgical Settlement: Bone Mineralization by Metalliferous Minerals
2021
Pb contents (13-53 mg kg−1) and pathological changes in almost complete cow skeletonsdiscovered in graves adjacent to Pb and Ag smelting furnaces active in the Silesian-Cracovian region, in the mid-12th century are reported in the article. In addition to Pb,elements such as Zn, Cd, Fe, Mn, Cd, and Ba characteristic of Zn-Pb-Ag ores in the regionwere identified. Bone fragments and the soil in which they had lain for almost 800 yearswere examined by SEM, EDS. XRD was used to identify minerals present in soils. Theenrichment of the bones with Zn, Pb, Fe, Mn, and Cd is associated with the remobilisationof elements from soil contaminated with primary and synthetic phase-rich metals. In bioticmat…