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Efficiency of chemical stabilization of a contaminated soil using amorphous manganese oxide
Tomášová, Zdeňka ; Ettler, Vojtěch (advisor) ; Trakal, Lukáš (referee)
Soil contamination by toxic metals and metalloids is currently one of the most discussed topics in the environmental sciences. Chemical stabilization of contaminated soils using amendments such as Fe, Mn and Al oxides belongs to one of the in situ remediation methods. Manganese oxides are naturally present in soils and they exhibit a number of properties for being efficient sorbents of toxic metal(loid)s, such as a low point of zero charge, a large specific surface and a structure that allows ion acceptance. The focus of this thesis is to determine efficiency of chemical stabilization of a smelter-contaminated soil using the amorphous manganese oxide (AMO) under various pH conditions. The agricultural soil polluted by emission from a Pb smelter (located in Příbram, Czech Republic; Pb 1 100 mg/kg, Zn 294 mg/kg, Cd 4.98 mg/kg, As 118 mg/kg and Sb 48.9 mg/kg) was amended with the AMO and incubated for 2 and 6 months. The soil was subsequently subjected to a pH-static leaching procedure in the pH range of 3-8. The presence of AMO in soil increased the soil natural pH from 5.77 to 6.59 and 6.23 after 2 and 6 months, respectively. The pH-static experiments indicated that no effect of the AMO treatment was observed for Cd and Zn, whereas the leaching of other contaminants (As, Cu, Pb, Sb) decreased...
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Contaminant mobility and toxicity in soil profiles in the Mufulira smelting area (Copperbelt, Zambia)
Konečný, Ladislav ; Ettler, Vojtěch (advisor) ; Frouz, Jan (referee)
ii SUMMARY The smelter in Mufulira is one of the several active copper smelters in Copperbelt area in Zambia. It had operated for almost 70 years and during that period all offgas and dust were released into the atmosphere. Six profiles, three of them beneath trees, were sampled in the distances of 3.6, 8 and 24 km from the smelter. Each profile consisted of 9-10 layers collected continuously from the topsoil till depth of 60-70 cm. Following parameters were measured for each layer: pH, TC, TS a CEC, then total concentration of Ag, As, Al, Fe, Co, Cr, Cu, Mn, Mo, Ni, Pb, Sb, Se, Sn, V a Zn and extractability by EDTA. The total concentrations of metals/metalloids were measured by ICP-OES and quadrupole- based ICP-MS. TC and TS were determined by thermal analysis and mobility of metals was assessed according to their extractability by EDTA. The aim of this work was to compare vertical distribution and mobility especially of these metals Co, Cr, Cu, Pb, V and Zn among profiles. Finally a standardized toxicity test was performed with ten selected layers (include all top soils) from all profiles. This reproductive test with Enchytraeus crypticus reflected how tested soil samples were suitable for living and reproducing this specimen of invertebrates. Generally the total concentrations of metals decreased in...
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Contaminant binding to colloids in water from a mining/smelting area
Walter, Dominik ; Ettler, Vojtěch (advisor) ; Faimon, Jiří (referee)
This study deals with the association of trace elements with colloids and particles in surface waters and groundwaters of mining and smelting district of Příbram. Colloids were studied using combination of cascade filtration a tangential flow ultrafiltration method to separate individual colloid fractions. Colloids were separated by filtration membranes with nominal pore size 0,8 μm, 0,45 μm, 0,1 μm, 100 kDa, and 5 kDa. Water samples were analyzed using ICP-OES, ICP-MS and HPLC. The data were used for thermodynamic modeling using PHREEQC-2 programme. The results show that major and trace elements can be divided into several groups, based on their abundance in individual size fractions. Most elements dominate in fraction of truly dissolved matter as dissociated ions (< 5 kDa), maximum concentration in colloid fraction is 5-20 % and almost exclusively in fraction 5 kDa - 100 kDa. Gradual decrease of concentration in all fractions at low ionic strength (1,2 mmol/l) was observed in case of elements such as As, Co, Cr, Si, Sb and U. Gradual decrease of concentration in several samples was observed for Cd, Fe, Pb, Mn and Zn. Dominant binding to colloids and particles in surface waters was observed for Fe and Pb, where these fractions accounted for over 90 %. The main factor influencing colloid...
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Binding of trace elements to colloids in MSW landfill leachates
Matura, Marek ; Ettler, Vojtěch (advisor) ; Pitter, Pavel (referee) ; Faimon, Jiří (referee)
1 SUMMARY The association of trace elements with colloids in leachates from closed and active municipal solid waste (MSW) was studied using the cascade filtration/ultrafiltration method. A study was carried out after long-term monitoring of seasonal variations of the leachate quality. Both landfills are situated in the vicinity of Prague and the closed landfill site represents a serious environmental risk for part of this city. In the first step, the evaluation of the long-term seasonal changes in the main and trace element contents in leachate from the closed landfill was performed and supplemented by investigation of precipitation/dissolution processes in the solid phases. It was shown that the quality of the leachate is strongly influenced by rain events, which are responsible for the dissolution of calcite and Fe oxides in the landfill body. This process leads to the release of Cu, Zn and Cd bound to these solid phases and to an increase in their concentrations in the leachate. The contents of the other element are significantly decreased by simple dilution. Therefore, the mobility of all the studied elements increases substantially during rain events. Monitoring of the seasonal variation in the leachate quality enabled us to determine the appropriate conditions for isolated sampling for studying the...
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Mercury in soils from mining and smelting districts in Zambia and Namibia
Podolský, Filip ; Ettler, Vojtěch (advisor) ; Vaňková, Maria (referee)
This master thesis is a part of project IGCP No. 594: "Assessment of Impact of Mining and Mineral Processing on the Environment and Human Health in Africa" and its goal is to determine and compare mercury content in 91 soil samples from mining and smelting areas in northern Namibia and 68 soil samples from the Copperbelt province in Zambia. Highest mercury concentrations in soils (with maximum 4.39 mg Hg kg-1 ) were found near the Tsumeb copper smelter in Namibia, whereas Hg concentrations were significantly lower in the Zambian Copperbelt (up to 0.392 mg Hg kg-1 ). Decreasing concentration of contamination corresponding to distance from the source of pollution has been confirmed at both localities. For an estimation of a possible source of contamination, 26 samples from smelting processes and waste were also taken. Highest concentrations of Hg were observed in Tsumeb again (219 mg Hg kg-1 in bag- house residue and 3,5 mg Hg kg-1 in processing wastes on tailing dams). Studies of mercury mobility in soil profile by correlation coefficients has shown Hg dependent on the content of sulfur and organic carbon, which indicates a dependence on the content of organic matter. Among metals and metalloids best correlations between Hg and Cu, As, Sb, Pb, and Zn were calculated. Because mercury is currently...
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Stability and efficiency of a new Mn-oxide based sorbent in contrasting soils
Knytl, Vladislav ; Ettler, Vojtěch (advisor) ; Komárek, Michael (referee)
Metal contamination of soils is one of the most important environmental problems throughout the world. One of the possible remediation technique of contaminated soils is based on chemical stabilization using various amendments. Due to their structure and sorption properties (pHZPC, specific surface, CEC etc.), Fe, Mn and Al oxides are suitable for this remediation technique. The focus of this diploma thesis is to evaluate the stability and the effectivity of the new synthetic amorphous Mn oxide (AOM) in soil samples with contrasting physicochemical parameters, mainly pH: soil N (pH 4,2), soil H (pH 5,4), soil S (pH 7,3). In a 90-day laboratory pot experiment with incubation of AMO in these soils we found that stability of AOM is strictly pH-dependent. Higher dissolution was observed in the most acidic soil N (mass loss up to 18%), whereas in alkaline soil S themass loss attained only 10%. The dissolution of AOM in acidic soils (N, H) was connected with a significant release of Mn into the soil pore water. For soils H and S the massive formation of secondary carbonate phases (rodochrozite - MnCO3, kutnahorite - (Ca,Mn)CO3) was detected on the AOM surfaces by X-ray diffraction analysis (XRD), transmission electron microscopy (TEM) and scanning electron microscopy (SEM). Granulometric measurements...
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Mercury in stream sediments from a mining/smelting area: Sampling campaigns 10 years apart
Sýkorová, Kateřina ; Ettler, Vojtěch (advisor) ; Navrátil, Tomáš (referee)
This master thesis compares mercury concentrations in 64 samples of stream sediments from the Břehové Hory ore district (Příbram, Czech Republic), where lead and silver were mined and processed. Sampling took place in May 2003, September 2012 and October 2013 with intention to assess the influence of floods in August 2002 and June 2013 on changes of the level of mercury contamination in the stream sediments. In all three sampling campaigns, the background concentrations near the headwaters of the stream were about 0.2 mg Hg/kg, as a consequence of the weathering of geological units. Because of draining the historical mining and smelting region, the highest concentrations reach 3.2 mg Hg/kg downstream the Březové Hory ore district. The source of this contamination are probably former ore processing plants and the failures of tailing ponds. Extensive transport occurs especially during flood events and as the result, contamination can occur not only in the stream, but also in the alluvium materials. The main point source of the contamination in the area is the secondary Pb smelter, but its influence on the concentrations of mercury in stream sediment is insignificant. Nevertheless, it is a possible source of the contamination of the stream sediments with lead, cadmium and zinc. The concentrations up to...
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Environmental characteristics of mineral waste from metallurgy
Vítková, Martina ; Ettler, Vojtěch (advisor) ; Bollinger, Jean-Claude (referee) ; Dijkstra, Joris J (referee)
Mineralogical and geochemical characteristics of metallurgical wastes from the Cu-Co smelters situated in the Zambian Copperbelt have been investigated. A number of instrumental analytical methods (XRD, SEM/EDS, EPMA, TEM/EDS) has been used to identify primary and secondary phases in smelter slags and dusts. A set of leaching experiments (CEN/TS 14997 pH-static test, EN 12457 batch test) in combination with geochemical modelling has been performed, with the emphasis on the leaching behaviour of potential contaminants and their release as a function of the pH. The effect of sample preparation on metal leachability from slag was also evaluated, considering the grain size reduction required by the standardised leaching protocols. Environmental and health risk assessments of the dust samples have been performed. It was shown that the main carriers of metals in the studied slags were Cu sulphides (bornite, digenite, chalcocite), Co sulphides (cobaltpentlandite), Co-bearing intermetallic phases and alloys. Copper and cobalt were detected in major silicates and spinels, substituting for Fe or Mg in their structures, and in glass. The presence of secondary metal-bearing phases observed on the slag surfaces indicated the reactivity of the slags on contact with water/atmosphere. It was reported that in...
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Experimental investigation of copper smelter fly ash dissolution in a tropical soil
Petráňová, Veronika ; Ettler, Vojtěch (advisor) ; Kříbek, Bohdan (referee)
In a laboratory pot experiment we investigated a time-dependent release of contaminants from smelter dusts into the soil water and soil. In the experiment we used smelter dusts from two different Cu smelters located in Copperbelt in Zambia (Mufulira and Chambishi). Experimental bags with 0.5 g of dust were placed into pots with 200 g of uncontaminated tropical soil (oxisol) and studied in a time frame of 504 h. Pots were irrigated by deionised water and maintained at the 80 % water holding capacity (WHC). Ten samplings of pore water were performed using the Rhizon pore water samplers. In soil waters, the major released contaminants were Cu, Co and Zn. Concentrations of Cu and Co in soil waters C (from soil with the dust from Chambishi) and M (from soil with the dust from Mufulira) increased during first 48 and 216 h, while concentration of Zn reached highest value in soil waters C and M in 24 and 144 h. This trend has not been observed for Pb, which was released in small amounts and obviously bound to soil constituents. Together with metals, sulfates were highly released into soil waters and affected the speciation of metals (formation of sulfate complexes). Compared to mass loss of the dust from Chambishi with low value (8%), the mass loss of dust from Mufulira after pot experiment were...
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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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