Spelling suggestions: "subject:"soil pollution 0nvironmental aspects"" "subject:"soil pollution anvironmental aspects""
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Soil contamination and plant uptake of metal pollutants released from Cu(In, Ga)Se₂ thin film solar panel and remediation using adsorbent derived from mineral waste materialSu, Lingcheng 15 June 2018 (has links)
The Cu(In,Ga)Se2 (CIGS) thin-film solar panels (TFSPs) are widely used in integrated photovoltaic (PV) and solar power systems because of their perfect PV characteristics and ductility. However, the semiconductor layers of these panels contain potentially toxic metals. In this study, the potential environmental pollution arisen by CIGS TFSP treated as construction trash at the end of their useful life was examined. Acid extraction was used to simulate leaching toxicity followed by burying CIGS TFSP material in different soils, namely a synthetic soil, a Mollisol, and an Oxisol, to determine whether metal pollutants might be released into the soil. A vegetable, Brassica parachinensis L. H. Bariley (VegBrassica), was selected to grow in these polluted soils to investigate the uptake of metals and their bioaccumulation. The simulative remediation of contaminated soils was carried out using a remediation module created by the combination of activated carbon and modified mineral waste material (MMWM) in this research. The activated carbon derived from the waste biomass material was produced by an environmental friendly method, and the MMWM was obtained through a thermal dehydroxylation treatment. The physiochemical properties of MMWM, with focusing on mineral phase transformation, were related to the changes in surface morphology due to dehydroxylation occurred during the process of thermal treatment of MMWM samples, and the adsorption performances of metal (lead, Pb) and organic compound (methyl orange, MO) onto this newly modified MMWM were studied. Furthermore, an end-of-life treatment method was designed and proposed for harmless disposal of CIGS TFSP. Various metals, including Pb, zinc (Zn), nickel (Ni), chromium (Cr), gallium (Ga), copper (Cu), indium (In) and aluminum (Al) were found to be released into the soil and caused contamination when scrapped end-of-life CIGS TFSP were buried, and the rates of metal release changed with the variations of both the amounts of CIGS TFSP material in the soil and the soil properties. The increases in concentrations of heavy metals such as Zn, Cu, Ni, Ga, Pb, In, and Cr were correlated with the amounts of CIGS TFSP material added in soils. The Pollution Index and the Nemerow Contamination Index calculated from our results confirmed that, when buried, the CIGS TFSP material polluted the soil. Plants grew well in the synthetic soil and the Mollisol, but those in the Oxisol showed prominent signs of chlorosis and died after 30 days. The bioaccumulation factor (BF) and concentration of Zn were 3.61 and 296 mg/kg, respectively in VegBrassica grown in the synthetic soil with 10% (200 g to 2 kg of soil) of added CIGS TFSP, while the BF and concentration of In were 3.80 and 13.72 mg/kg, respectively in VegBrassica grown in the Mollisol, indicating that bioaccumulation occurred. The thermally treated MMWM samples showed morphological transformation mainly on surface based on the scanning electron microscopy (SEM) observations, and an increasing trend in BET specific surface area (SSA) from 120 to 500 ℃ followed by a decreasing trend up to 1000 ℃. Thermal modification had successfully improved Pb adsorption capacity up to 515 mg/g, corresponding to MMWM modified at 600 ℃ with an SSA of 6.5 m2/g. The MO adsorption capacity was also improved after thermal treatment of MMWM, which performed the best adsorption of 87.6 mg/g at 400 ℃. The adsorption of Pb and MO were mainly chemisorption and monolayer coverage, as pseudo-second-order model and Langmuir equation displayed good relationships of correlation for Pb and MO adsorption data. It is therefore indicated that the newly designed soil remediation modules could significantly remove metals from the contaminated soils. In summary, c
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Trace metal speciation and bioavailability in urban contaminated soilsGe, Ying, 1974- January 1999 (has links)
No description available.
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Methods to predict and reduce trace metal levels in lettuce grown on contaminated urban soils = Méthodes pour prédire et réduire les métaux traces dans la laitue cultivés sur des sols contaminésTambasco, Giuseppe. January 1998 (has links)
No description available.
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Site specific evaluation of urban brownfields contaminated with trace metalsMurray, Patricia, 1964- January 1999 (has links)
This thesis is part of a broader project that examines three different approaches to evaluating trace metal contamination in urban brownfields: the measure of total soil metals; calculating bioavailable metals; and the use of species as bioindicators of trace metals in soils. Chapter 1 discusses the problems inherent in each approach such as; inconsistent results due to differences in techniques, extrapolation from laboratory to field, and the influence of species differences and environmental conditions. Chapter 2 is a site description measuring biodiversity, community structure and activity of three urban brownfields. The site description was used to select organisms that were subsequently evaluated for their usefulness as bioindicators of trace metals (chapter 3). Of the three plant species used (dandelion, bladder campion, and chicory), dandelion has the possibility of being a suitable bioindicator of Cd, Ni, and Zn, while bladder campion may be suitable for evaluating Cd, Ni, Pb, and Zn.
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Chemical pollution arising from heavy inorganic industries in Richards Bay - an assessment.January 2004 (has links)
The industrial port of Richards Bay on the eastern seaboard of KwaZulu-Natal, South Africa has undergone
rapid growth over the last 25 years. This industrial growth has inevitably led to an increase in the anthropogenic
pollutant inputs in the area. However, the degree of this contamination has not previously been assessed not
been accompanied by an awareness of its environmental impacts. This project serves to assess the current
environmental situation of the area and provide background levels against which the environmental impacts of
further growth in the area can be assessed.
The main pollution point sources in the area were identified as a pulp and paper plant, a sulfuric acid/fertiliser
plant and aluminium smelters. The chemical and physical processes involved within these industries were
identified and discussed in detail. The common inorganic pollutants emitted by these industries were identifies
as trace metals, sulfur dioxide, NOx gases and fluoride. It was these pollutants that therefore became the focus of
this study.
Reservoirs within Richards Bay that may become sinks for contamination were identified and water, sediment
and soil samples were taken from these reservoirs. The samples were analysed for trace metal contamination,
pH, alkalinity and fluoride levels.
Analysis of the acidity and alkalinity of water, sediment and soils samples demonstrated that there is presently
no long-term acidification of the environment in Richards Bay. The only samples that showed increased acidity
were the soils taken from the roadside sites immediately outside the industries. This lack of overall acidification
indicates that, at present, there are no detrimental effects of acidic emissions on the hydrosphere and geosphere.
Only cursory investigations were conducted into the fluoride levels found in water samples. None of the samples
analysed demonstrated detectable amounts of fluoride present.
Comprehensive trace metal analyses were performed on the water, sediment and soil samples through the use of
ICP-AES. Levels obtained were compared with levels from samples taken from relatively uncontaminated
background sites. Trace metal analysis indicated contamination of the freshwater reservoirs when compared
with the background, while the soils and saltwater reservoirs remain largely uncontaminated. However, the
contaminated areas did not show levels greater than quality guideline concentrations.
Further studies should be conducted with regards to the trace metal contamination of the biosphere and the
bioavailability of the contaminants already present in the waters, sediments and soils. More detailed
investigations should also be conducted into the levels of atmospheric pollutants and fluoride levels in all
reservoirs. / Thesis (M.Sc.) - University of KwaZulu-Natal, Pietermaritzburg, 2004.
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Site specific evaluation of urban brownfields contaminated with trace metalsMurray, Patricia, 1964- January 1999 (has links)
No description available.
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