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Anthropogenic particles in soils of historical mining areas
Shalabai, Anastasiia ; Ettler, Vojtěch (advisor) ; Tuhý, Marek (referee)
Soils are an important receptor of anthropogenic contamination. The aim of this bachelor's thesis was to summarize the information about the anthropogenic particles in soils, characterize their chemical and mineralogical composition and find out in which forms the risk elements are found in them. An experimental part of the work was carried out on samples of soils from historical mining and ore processing areas (Jihlava, Příbram) and, for comparison purposes, on an urban soil (Prague - Suchdol) in order to determine the binding of contaminants in particles of anthropogenic origin using a combination of portable X-ray fluorescence (pXRF), optical microscopy, scanning electron microscopy (SEM) and electron probe micro-analyzer (EPMA). Dust particles in the studied soils originating from ore mining and processing and burning processes are especially enriched in As, Pb, Zn and Fe. The key contaminants are mainly bound in silicates, glass, oxide phases and sulfides. Iron is also present in the form of metallic droplets. The highest concentration of potentially toxic elements was found in samples from Příbram (mg/kg): As (1514), Pb (7970), Zn (10053). Arsenic was determined in pyrite (up to 2.27 wt.%), which typically is of ore mining. Lead is mostly bound in glass in slag particles (up to 25.12 wt.%...
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Percolation column tests and investigation of contaminant leaching from mineral wastes: theory and experiment with metallurgical slag
Gottvald, Matouš ; Ettler, Vojtěch (advisor) ; Vítková, Martina (referee)
Leaching represents an essential concept related to the natural processes that occur at the contact between solids and solutions. The leaching properties of mineral wastes point to the mobility of contained contaminants in various scenarios and, thus, the environmental risk of the wastes. Experimental tools have been developed to determine the leachability over a range of conditions and to be a part of the waste evaluation workflow. Special emphasis is given to the dynamic column leaching tests that approximate percolation occurring in the field and enable to describe the time dependence of leaching. Processes that are observed in full-scale systems may substantially differ from those in the laboratory simulations. Apart from the field experiments and geochemical modelling, also modifying the original leaching test protocols expands our awareness of the mineral waste behaviour. We performed a column leaching test. Secondary Pb metallurgical slag coming from the Pb-scrap recycling was leached according to the standardised column leaching test EN 14405 as a part of broader research on the leachability of slag exposed to the wetting-drying cycles. The cumulative leached mass of both metal and major elements was lower compared to the previous turn; bulk leached masses of the main contaminants related...
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Mineralogy and bioaccessibility of contaminants in wastes from mining and processing of Cu-Ni ores from Selebi-Phikwe (Botswana)
Hladíková, Karolína ; Ettler, Vojtěch (advisor) ; Kříbek, Bohdan (referee)
Mining, processing, and metallurgy of Cu-Ni ore in Selebi-Phikwe, Botswana, resulted in a large amount of solid waste material in the form of overburden, slag dumps, tailings, and smelter emissions. Fine particles could spread by wind and contaminate nearby soils or pose a risk for human health by inhalation or unintentional ingestion. Samples of granulated slag, flotation tailings, and contaminated soil were subjected to a multi-method mineralogical and geochemical analysis (ICP-MS, XRD analysis, EPMA, SEM, Raman spectrometry) to identify the distribution and binding of inorganic contaminants. Especially, the fine dust fractions <48 μm and < 10 μm, which could potentially pose a risk through ingestion or inhalation, were studied. Trace elements analysis indicated that slag is enriched in Cr (up to 499 mg/kg), Co (up to 857 mg/kg), Cu (up to 9600 mg/kg), Ni (up to 7000 mg/kg) and Zn (up to 690 mg/kg). Flotation tailings contain relatively high concentrations of Ni (up to 3000 mg/kg) and contaminated soil is especially enriched in As (up to 53,8 mg/kg), Cd (up to 28 mg/kg), Cu (up to 3810 mg/kg), Ni (up to 2790 mg/kg) and Pb (up to 181 mg/kg). The finer dust fraction <10 μm is generally more metal(loid)-rich than the <48 μm fraction. The main contaminant hosting phases in all the studied samples are...
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Mobility of trace elements in tropical soils
Kindlová, Helena ; Ettler, Vojtěch (advisor) ; Vaněk, Aleš (referee)
This bachelor thesis is focused on mobility of trace elements in highly weathered tropical soils. In the first part of the thesis, the taxonomy and classification of tropical soils, processes of their formation and occurrence throughout the world are explained. Basic properties of tropical soils with emphasis on the trace element mobility are mentioned in the second part. The final part of the thesis is dedicated to the potential sources of trace elements in tropical areas, their forms and speciations, and in particular binding to individual soil constituents.
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Use of geochemical archives for the investigation of historical Hg deposition
Sýkorová, Kateřina ; Ettler, Vojtěch (advisor) ; Zuna, Milan (referee)
Human activities affect fluxes of mercury into the atmosphere and modify its biogeochemical cycle. Current emissions, concentrations and deposition rates of mercury are measured by a series of monitoring networks. For the estimation of historical deposition rates of mercury, we use numerous geochemical archives, which represent long-term records of atmospheric pollutants Trends in concentrations and accumulation of mercury well correspond to trends in burning of fossil fuels, industrialization and use of mercury during the 19th and 20th century. Peat bogs as geochemical archives are suitable for studying these trends. Further research will be devoted to deciphering the processes of sequestration and cycling of mercury in peatlands, especially the role of vegetation in these systems.
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Usage and environmental stability of MSWI bottom ash in road construction
Pospíšilová, Eliška ; Ettler, Vojtěch (advisor) ; Šebek, Ondřej (referee)
This bachelor thesis is a compilation of scientific and technical literature focused on treatments of municipal solid waste incinerator (MSWI) bottom ash such as carbonation or electro-kinetic remediation for the purpose of the decrease of the contaminant lechability. The carbonation the cheapest solution and is generally used as a first stage of MSWI bottom ash treatment. The second part of the thesis deals with possible applications of MSWI bottom ash for the construction purposes. Addition of bottom ash to the concrete is used as the alternative of natural purposes. Addition of bottom ash to the concrete is used as the alternative of natural gravel. Due to similar physical properties with crushed aggregate, bottom ash is also commonly used as a subbase of roads or pavement in numerous countries. Mixed bottom ash with the Portland cement can also find some applications as a light concrete with similar physical and mechanical properties.
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Transformation of fly ash from Pb metallurgy in soils
Valigurová, Radka ; Ettler, Vojtěch (advisor) ; Komárek, Michael (referee)
The fly ash from secondary lead metallurgy was placed in two different soils in order to investigate the kinetics of release (in a time horizon of 504 h) and mobility of metals/metalloids in soil water and soil. Uncontaminated soils used for the pot experiment were two: acidified forest soil N and agricultural soil H. An experimental bag containing 0.5 g of fly ash was placed in a pot with 200 g of soil, which was watered using deionised water at the 60 % water holding capacity (WHC) level. Using Rhizon pore water samplers the soil solution was regularly sampled and subsequently analysed. The soil solution analysis was supplemented by the geochemical speciation-solubility modelling using the PHREEQC-2 code and the mineralogical investigation of solid phase. For Cd, Zn and As the release in soil water had similar behaviour in time: during first 96 hours of the experiment their concentration increased up to maximum values and then slowly decreased till the end of experiment. This trend has not been observed for Cu, Pb and Sb, being tightly bound to secondary phases newly formed directly in the fly ash or to soil constituents, or indicating possible resistance to leaching. Weight loss after the experiment for the fly ash was in both soils approximately 60 %, indicating high level of its dissolution....
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Experimental in situ transformation of smelting wastes in soil systems
Jarošíková, Alice ; Ettler, Vojtěch (advisor) ; Hiller, Edgar (referee) ; Doušová, Barbora (referee)
Metallurgical activities are one of the important sources of environmental pollution, especially due to inappropriate treatment of waste materials containing potentially harmful elements. Soils in the vicinity of smelting operations are the main target reservoirs for these emitted contaminants. The aim of this study was to depict reactivity of copper smelter flue dusts and slags in aqueous and soil environments using laboratory and field experiments. Slags exhibited high concentrations of As (up to 0.95 wt.%), Cu (up to 2.4 wt.%), Pb (up to 1.02 wt.%), Sb (up to 0.37 wt.%), and Zn (up to 2.45 wt.%). Copper and other metal(loid)s were predominantly bound in sulphides, especially bornite, digenite, chalcocite, and galena. Flue dusts were mainly composed of As2O3 phase (arsenolite and claudetite), with minor amounts of gypsum, galena, quartz and covellite. The main contaminants in the dust were As (53.3 wt.%), Pb (3.41 wt.%), Sb (1.26 wt.%), Zn (1.41 wt.%), Cu (1.07 wt.%) and Bi (0.80 hm.%). The leaching tests performed in the pH range of 3-12 indicated that the release of metal(loid)s from both types of metallurgical wastes was highly pH-dependent. During the leaching in deionised water, up to 42 mg/kg As was released from slags and up to 52.6 g/kg was leached from the flue dust; the latter highly...
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Mercury emissions from anthropogenic sources
Podolský, Filip ; Ettler, Vojtěch (advisor) ; Hojdová, Marie (referee)
This bachelor thesis is focused on mercury fluxes in the environment wit the emphasis on the industrial pollution. Based on general information about mercury and characteristics of it's compounds, occurrence in the atmosphere, hydrosphere and pedosphere mercury fluxes and behaviour of mercury in the global biogeochemical cycle are described. The main topic of this thesis is to overview all sectors, which are the main contributors to the global mercury pollution. The largest producers of the Hg emissions are coal-fired power plants, artisanal small-scale mining and the mining/production of non-ferrous metals. Conclusions are dedicated to comparisons of natural and anthropogenic emissions of Hg in the present and in pre-industrial times.
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Variability of water quality parameters in selected reservoirs in Prague
Stará, Eva ; Ettler, Vojtěch (advisor) ; Chalupová, Dagmar (referee)
Small water reservoirs in urban areas have important landscape-forming and environmental roles. However, numerous anthropogenic activities can influence the water quality in these urban ponds. This thesis evaluates and compares the water quality in selected ponds in Prague area (Motol, Stodůlky, Háje) by means of regular water monitoring between May and November 2013. Parameters commonly used as indicators of anthropogenic load were monitored (NO3 - , NH4 + , PO4 3- , Cl- , dissolved oxygen, chemical oxygen demand) and supplemented with the investigation of other chemical and physico-chemical parameters (alkalinity, acidity, water hardness, pH, Ca2+ , NO2 - , specific conductivity). Data were evaluated using Czech technical norm (ČSN - EN 75 7221), which defines five categories of surface water quality. Our data indicated that surface water from reservoirs in Motol exhibited the best water quality (1st category), reservoirs from Stodůlky were slightly polluted and reservoirs from Háje exhibited the poorest water quality (with some parameters exhibiting values corresponding to the 4th category). We found statistically significant correlations between the alkalinity, water hardness, COD and concentrations of NO3 - , Ca2+ , Cl- and PO4 3- . Moreover, numerous parameters are dependent on cumulative...
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