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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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Tree rings dendrochemistry near Cu smelter
Jarošíková, Alice ; Mihaljevič, Martin (advisor) ; Hojdová, Marie (referee)
Nkana smelter belonged to the main sources of contamination by trace elements (especially Cu and Co) in the area of African city Kitwe (Copperbelt, Zambia). The main objective of this study was to compare elemental and isotopic composition of Zambian soils and tree rings, and to investigate biogeochemical processes between plants and soils in contaminated and uncontaminated environment. Elemental composition (Cu, Co, Cr, Mn, Fe, Zn, Pb, Cd, Hg and Tl) and isotopic composition of Cu (63 Cu/65 Cu) were determined in soils and tree rings of pine trees (Pinus latteri, Pinus kesiya) using ICP-MS , AMA and MC ICP-MS. Our results demonstrated that soils and tree rings were both affected by mining and metallurgical activity. Increasing content of elements with depth is the result of the mobility of the elements in uncontaminated soil profile. Soil from contaminated site had the highest metal contents especially in the upper part of the soil profile as a result of continuous contribution of metallurgical components during long-term smelter operation. Fractionations of Cu isotopes in soils were caused primarily by interactions with plants. Concentration changes that some elements showed in the individual tree rings could be the effect of variable intensity of pollution in the area. In the case of Cu, however,...
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Pb-Zn slags from Kabwe (Zambia): mineralogy and gastric bioaccessibility of contaminants
Štěpánek, David ; Ettler, Vojtěch (advisor) ; Jarošíková, Alice (referee)
This bachelor thesis focuses on slags originating from Imperials Smelting Process (ISP) and Waelz metallurgical process in Kabwe, Zambia, where Pb-Zn ores have been historically processed. The aim of this thesis was to characterize the chemical and mineralogical compositions of the slags and to assess the bioaccessibility of contaminants (Cd, Pb, V, Zn) from the slag dusts in simulated gastric conditions to evaluate the potential health risks for humans. Slags are particularly enriched in Pb (up to 62700 mg/kg) and Zn (up to 190300 mg/kg). Main contaminants (Pb, Zn, V) are bound in the slag glass, Fe and Mn oxides and hydroxides and carbonates. Vanadium is largely bound in complex phases such as vanadates, phosphates and sulphates. Contaminant concentrations are higher in slag dust (fractions <48 µm and <10 µm) than in the original granulated slag samples and ISP slags generally exhibit higher concentrations than the Waelz slags. During the leaching in simulated gastric conditions (0.4 M glycine, pH 1.5, 1 hour at 37 řC), abundant slag glass, (phyllo)silicates and carbonates were dissolved. In contrast, Fe oxides and hydroxides remained in the residue and were therefore stable during the leaching. Relative bioaccessibility of contaminants was rather high (up to 82 % Cd, 92 % Pb, 100 % V and 81 %...
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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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Tree rings dendrochemistry near Cu smelter
Jarošíková, Alice ; Mihaljevič, Martin (advisor) ; Hojdová, Marie (referee)
Nkana smelter belonged to the main sources of contamination by trace elements (especially Cu and Co) in the area of African city Kitwe (Copperbelt, Zambia). The main objective of this study was to compare elemental and isotopic composition of Zambian soils and tree rings, and to investigate biogeochemical processes between plants and soils in contaminated and uncontaminated environment. Elemental composition (Cu, Co, Cr, Mn, Fe, Zn, Pb, Cd, Hg and Tl) and isotopic composition of Cu (63 Cu/65 Cu) were determined in soils and tree rings of pine trees (Pinus latteri, Pinus kesiya) using ICP-MS , AMA and MC ICP-MS. Our results demonstrated that soils and tree rings were both affected by mining and metallurgical activity. Increasing content of elements with depth is the result of the mobility of the elements in uncontaminated soil profile. Soil from contaminated site had the highest metal contents especially in the upper part of the soil profile as a result of continuous contribution of metallurgical components during long-term smelter operation. Fractionations of Cu isotopes in soils were caused primarily by interactions with plants. Concentration changes that some elements showed in the individual tree rings could be the effect of variable intensity of pollution in the area. In the case of Cu, however,...
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In situ weathering experiments of sulphides and silicates
Jarošíková, Alice ; Mihaljevič, Martin (advisor) ; Drahota, Petr (referee)
Weathering is a natural process which is occuring on the Earth's surface. Its effect on minerals and other materials is significant. Besides mechanical alteration, the result of weathering can reach the chemical reactions, which can lead to contamination of the environment (e.g. ground water and soils). Not only for this reason has weathering become an object of intensive studies. In situ weathering experiments are one way of research. The aim of this bachelor thesis is to review the advantages and disadvantages of these experiments, to describe their course and the complications which can happen during the experiments, and how to use knowledge of these observations. Attention is also focused on several concrete experiments which were concerned with the weathering of sulphides and silicates, and where it is possible to observe these things on them.
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