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Mobility of chromium and nickel in naturally contaminated soils
Kvapil, Jindřich ; Ettler, Vojtěch (advisor) ; Vaněk, Aleš (referee)
Soils developed on ultramafic rocks are relatively rich in trace elements, e.g. Cr, Co and Ni. Soils studied here and developed on serpentinites in the southern Bohemia exhibit high concentrations of these elements with up to several thousands mg/kg. Particularly soils with high Ni concentrations host specific vegetation and are are poor in nutrients. In this thesis we sampled two soil profiles located in the vicinity of closed Ni mining near Křemže in the southern Bohemia. Analyses of physicochemical parameters of soils, total concentrations of elements and their extractability using EDTA targeting "bioavailable" fraction were carried out. Concentrations of studied elements were the following: 27,1 - 423 mg Co/kg, 90,3 - 1190 mg Cr/kg, 170 - 4950 mg Ni/kg. Concentrations of Ni, Co and Cr significantly correlated with Fe (R2= 0.76-0.99) and were higher for agricultural soil profile with an increase as a function of depth. Maximum "bioavailable" concentrations were 47.6 mg Co/kg, 2.95 mg Cr/kg and 163 mg Ni/kg. Powered by TCPDF (www.tcpdf.org)
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Mineralogy of particulates from semi-arid soils polluted by mining and smelting and their transformation/re-mobilization during bushfires
Tuhý, Marek ; Ettler, Vojtěch (advisor) ; Kříbek, Bohdan (referee)
This thesis is focused on biomass-containing topsoils from a highly contaminated semi-arid area in the vicinity of mining and smelting operations in Tsumeb and Kombat in the northern Namibia. The highest concentrations of inorganic contaminants were found in samples from Tsumeb and attained the following values (mg/kg): As 1920, Cd 81, Cu 5840, Hg 7,66, Pb 4880, Sb 266, Zn 3310. X-ray diffraction analysis (XRD), scanning electron microscopy (SEM) and electron microprobe analysis (EPMA) have been used for determination of mineralogical composition of particulates adhering to surfaces of biomass and occurring in the heavy mineral fraction of topsoils. Quantitative partitioning of contaminants within individual mineral phases has been determined using autoSEM; contaminants were mainly bound in the slag glass (As: 16.7 %; Cu: 12.7 %; Pb: 26.2 %; Zn: 33.9 % of total concentration) and in metal(loid)-rich Fe-hydroxides (As: 14.4 %; Cu: 7.7 %; Pb: 21.6 %; Zn: 32.5 %). On biomass- rich topsoil samples, we have experimentally proved that bushfires can be responsible for transformation and re-mobilization of contaminants. Mercury is completely released at temperatures around 300 řC. In the same temperature range, also As anad Sb are released due to arsenolite (As2O3) thermal degradation. Cadmium is released...
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Stability of amorphous Mn oxide-based sorbent as a function of pH
Tomášová, Zdeňka ; Ettler, Vojtěch (advisor) ; Vítková, Martina (referee)
Soil systems contaminated by toxic metals and metalloids from anthropogenic sources present hazard for human health and other environmental compartments. Chemical stabilization using the Fe, Al and Mn oxides is one of the potential decontamination techniques. Manganese oxides exhibit a number of properties for being efficient sorbents of toxic metals, such as low point of zero charge, structure that allows ion acceptance and large specific surface. The focus of this thesis is to determine the stability of novel synthetic amorphous manganese oxide (AMO) as a function of pH using the pH-static leaching test. Manganese was released into the solution, with decreasing concentration in leachate as a function of pH: Mn concentration at pH 3 was 34 100 mg/L and at pH 8 only 90 mg/L. The data show that the solid phase mass loss is clearly dependent on the pH value, with the mass loss of 98,4 % and 11,2 % at pH 3 and 8, respectively. On the AMO surfaces, the newly formed crystals of rodochrosite (MnCO3) were observed; they partly control the Mn release at pH > 5. Based on the observed pH-dependent stability, it appears that the use of AMO as a sorbent of toxic metals could be a suitable method for neutral or alkaline soils, while its application for acidic soils seems to be unsuitable. Powered by TCPDF (www.tcpdf.org)
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Distribution, binding and mobility of Ni in soil in the closed Ni mining area in the vicinity of Křemže
Pipková, Zuzana ; Ettler, Vojtěch (advisor) ; Vaněk, Aleš (referee)
Soils in the vicinity of Křemže in the Southern Bohemia are developed on altered ultrabasic rocks. The occurrence of Ni-hydrosilicate and Fe-rich ores in this area lead to their mining mainly during 19th century, then during the World War II. This thesis is focused on distribution and availability of Ni, Cr and Co and accompanying elements in soils at former mine and prospection sites (2 soil profiles and 32 topsoil samples at historical surface mine area). In all soil samples, physico-chemical parameters (pH, TOC, TS) and bulk concentrations of Al, Ca, Co, Cr, Cu, Fe, Mg, Mn, Ni, Pb and Zn were measured. In addition, deionised water, DTPA and EDTA extracts were used to determine the (bio)availability and mobility of these elements. Some of trace elements were found in elevated concentrations in the mining area topsoils; mean Ni: 1175 mg/kg (range 545-2849 mg/kg), mean Cr: 416 mg/kg (240-849 mg/kg), mean Co: 127 mg/kg (65-238 mg/kg), mean Fe: 49155 mg/kg (30460-113800 mg/kg), mean Mg: 12648 mg/kg (8795-18770 mg/kg) and mean Mn: 1480 mg/kg (1028-2319 mg/kg). In soil profiles the Ni availability decreased with depth. In the uppermost organic O horizon in forest soil profile, 19.5 % and 23.8 % of total Ni was extracted by DTPA and EDTA, respectively. The extractabilities are decreasing down to mineral...
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Use of LCA (life cycle assessment) in environmental sciences
Francová, Michaela ; Ettler, Vojtěch (advisor) ; Vítková, Martina (referee)
The goal of this bachelor thesis is to describe the analytical method called the Life Cycle Assessment (LCA) and to show its practical applications in case studies especially in waste management. The LCA method consists of four phases. The first phase is the definition of the intention and volume of the study, which includes the subject, the recipient, the place concerned and the purpose of the study together with specifications of the scope of product system. The second phase deals with the life cycle inventory. The investigators collect the accessible data on individual inputs and outputs of the product system, which are consequently embedded into the inventory chart. The third phase applies to the assessment of the life cycle impact on predefined categories using the impact categories indicators. The final phase summarizes the interpretation of the life cycle, its intelligibility for the submitter being mainly considered.
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Spatial distribution of heavy metals in aluvial sediments of Litavka river and reconstruction of contamination history
Kotková, Kristýna ; Mihaljevič, Martin (advisor) ; Ettler, Vojtěch (referee)
SUMMARY: This thesis is focused on identification of spatial distribution of Pb, Zn and Cu pollution in floodplain sediments of the Litavka River and reconstruction of its pollution history related to mining and metallurgy of Ag, Pb and Zn in the Příbram area. Sampling was performed in floodplain and sediments were analysed by X-ray fluorescence spectroscopy (ED XRF) in aim to understand the distribution of the target elements in the floodplain fill. The results of ED XRF were calibrated by analyses of selected sediment samples by inductively coupled plasma mass spectrometry with (ICP- MS). The same method was used to determine ratios of lead stable isotopes 206 Pb and 207 Pb. Additionally, magnetic susceptibility was measured, granulometric analysis of selected samples was performed, and cation-exchange capacity (CEC) was determined. The aim of the work was to attempt to reconstruct history of pollution of the floodplain sediments. Sediment dating was performed by 14 C, 137 Cs and 210 Pb. Key words: aluvial sediment, contamination, heavy metals, reconstruction
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"Waste-to-Energy" concept and its environmental implications
Koretz, Michal ; Ettler, Vojtěch (advisor) ; Baloch, Tomáš (referee)
Summary: This work focuses on assessing the environmental implications of the concept of waste-to-energy. An integrated waste management systems are described, which are instruments for extracting energy from municipal solid waste. It compares these systems by method of life-cycle-assessment (LCA). This work describes the municipal solid waste as a raw material for combustion process with integrated treatment technology. It focuses on the global problem and reason of inventing waste management system, the increasing volume of waste produced by mankind and its solution using the concept of waste-to-energy. This work also addresses the issue of over-representation of landfilling in waste management systems of different nations. Finally, the paper deals with the impacts associated with emissions of contaminants arising from the waste combustion.
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