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Key factors in soil organic matter accumulation
Vindušková, Olga
Soil organic matter (SOM) is highly important for soil quality and the global carbon cycle. SOM content is influenced by a complex interplay of many different factors such as time, climate, parent material, vegetation, and others. The effect of time is often studied using the chronosequence approach using a set of study sites differing in age but comparable in other soil-forming factors. The effect of other factors can be studied by comparing two or more chronosequences. An important assumption of these approaches is that the SOM quantification methods produce comparable results both among sites of each sequence and among different sequences. In this thesis, I explored the key factors in SOM accumulation and dealt with SOM quantification methods. I studied SOM accumulation in two model situations - in post-mining sites after open-cast coal and oil shale mining and in landslides in the Western Carpathians. The results of this thesis are summarized in one book chapter accepted for publication and four papers, out of which three have been published and one is prepared for publication in an international journal with impact factor. The key factor affecting the rate of SOM accumulation after a major disturbance is time. The accumulation rates found in the first 40 to 100 years in both post-mining sites...
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Radiation exposure in coal miners
BÁŇOVÁ, Denisa
The bachelor thesis focuses on a problematics of radiation load of miners during coal mining. This topic is something that public and miners themselves are not aware of that well. The thesis sets following goals: To chart radiation load of miners during coal mining and the awareness of miners about risks of their job. For the theme were also set following research questions: How big is the rate of radiation exposure of miners during coal mining? Is there considered any radiation protection for miners? At what rate do the miners perceive threats associated with working at coal mine? Which risks the miners encountered during their work experience? How big is the awareness of miners about the threat of radiation load? The theoretical part of this bachelor thesis classifies and sets general characteristics of coal and its most significant coal deposits. Furthermore, the thesis describes natural radionuclides and its content in rocks, radiation load of miners and other risks connected to mining. The last section of theoretical part describes radiation protection, safety and protection of health at work. The practical part was processed based on literature study and qualitative research. For data collection was used semi-structured interview with miners which formerly worked at coal mines and with miners which are still actively working at mines. Furthermore, was conducted an interview with specialist which focuses on ionizing radiation sources in a form of industrial applications. After the analysis, the research questions can be answered as follows. According to studied literature can be concluded that radiation load of miners does exist. However, from conducted interviews emerged that minors do not know much about this problematic and most of them does not even consider radiation load as a threat. The radiation protection in Czech coal mines is regulated by legislation. Based on the valid legislative the average volume activity of radionuclides in the air must be measured in work environments with material containing increased content of natural radionuclides. However, the miners reported that they did not notice any radiation measurement in coal mines. From this statement can be considered that there are no exceeding levels set by legislation at coal mines where questioned miners worked. Other possibility might be that nobody deals with it which is indicated in the interview with radiation application specialist. Some miners realize threats connected to their work and some of them do not. Some miners reported gusts, shaking, presence of methane and coal dust, various injuries and more. Those who did not report specific threats responded that they do not consider these as threats after several years working at mines. Respondents reported a big amount of threats which they encountered at their work. Amongst others were mentioned gusts, accidents, shaking, stone falls, variable temperatures, risk of occupational disease, possibility of methane explosion, presence of noise and vibrations when working with machines.
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Key factors in soil organic matter accumulation
Vindušková, Olga
Soil organic matter (SOM) is highly important for soil quality and the global carbon cycle. SOM content is influenced by a complex interplay of many different factors such as time, climate, parent material, vegetation, and others. The effect of time is often studied using the chronosequence approach using a set of study sites differing in age but comparable in other soil-forming factors. The effect of other factors can be studied by comparing two or more chronosequences. An important assumption of these approaches is that the SOM quantification methods produce comparable results both among sites of each sequence and among different sequences. In this thesis, I explored the key factors in SOM accumulation and dealt with SOM quantification methods. I studied SOM accumulation in two model situations - in post-mining sites after open-cast coal and oil shale mining and in landslides in the Western Carpathians. The results of this thesis are summarized in one book chapter accepted for publication and four papers, out of which three have been published and one is prepared for publication in an international journal with impact factor. The key factor affecting the rate of SOM accumulation after a major disturbance is time. The accumulation rates found in the first 40 to 100 years in both post-mining sites...
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THE USE OF SINTERED ARTIFICIAL AGGREGATES PRODUCED FROM SOLID ENERGETIC WASTE FOR CONCRETE.
Batelka, Michal ; Stehlík, Michal (referee) ; Kolář,, Karel (referee) ; Cigánek,, Jindřich (referee) ; Adámek, Jiří (advisor)
This work deals with issues aimed at the possibility of treating the material which has not been used yet – coal tailings. The work includes among others the production, its optimalization and utilization of a new type of lightweight artificial aggregate in the process of production of concrete. The possibility of manufactured the artificial aggregate is dealt with the principle of self-burning of the raw material's batch at the agglomerative grate. The optimalization of the burning process was performed both with the homogenous and the layered batch. Further part of the work focuses on the fabrication of diverse types of concrete and determination of their parametres. This section is significantly extended with the comparison of basic physical and specific properities of the new type of concrete with those of the commonly produced types. The last part of presented work deals with the ecological - economic situation of these issues. The proposed solution points to the possibility of utilization of the coal tailings which are put to the tailings heaps. It was managed to optimize the burning process and to find the most convenient system for storing the raw material's batch at the agglomerative grate. Next, it was proved that the types of concrete produced with a new sort of aggregate are also suitable for fabricating the construction concrete with the strength above the border of 50 MPa, which are applicable even in harder conditions. These sorts of concrete also have a lower volume weight and very good bending properties. The major finding, which underlines the contribution of this work, is that the up to now unused material is suitable for fabrication of relatively high-quality and thermally stable aggregate of strength on the border of 5 MPa, which can be use for fabricating concrete with very good results even in this field. Another great contribution of this work can surely be the fact, that a preliminary economic balance of the manufacturing pr
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Boilers for solid fuel
Hotový, Michal ; Štelcl, Otakar (referee) ; Baláš, Marek (advisor)
The task of this bachelor thesis is write up a research about solid fuel boilers and describe solid fuels. In second part of bachelor thesis I make an experiment. I measure an emission and efficient burning wood and coal.
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Key factors in soil organic matter accumulation
Vindušková, Olga ; Frouz, Jan (advisor) ; Borůvka, Luboš (referee) ; Šarapatka, Bořivoj (referee)
Soil organic matter (SOM) is highly important for soil quality and the global carbon cycle. SOM content is influenced by a complex interplay of many different factors such as time, climate, parent material, vegetation, and others. The effect of time is often studied using the chronosequence approach using a set of study sites differing in age but comparable in other soil-forming factors. The effect of other factors can be studied by comparing two or more chronosequences. An important assumption of these approaches is that the SOM quantification methods produce comparable results both among sites of each sequence and among different sequences. In this thesis, I explored the key factors in SOM accumulation and dealt with SOM quantification methods. I studied SOM accumulation in two model situations - in post-mining sites after open-cast coal and oil shale mining and in landslides in the Western Carpathians. The results of this thesis are summarized in one book chapter accepted for publication and four papers, out of which three have been published and one is prepared for publication in an international journal with impact factor. The key factor affecting the rate of SOM accumulation after a major disturbance is time. The accumulation rates found in the first 40 to 100 years in both post-mining sites...
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Modernizace spalovacích zařízení v elektrárně Poříčí
Huvar, Karel
The task of this thesis is the introduction to combustion facilities modernization issues of the Poříčí power plant. Summary and content of the valid legislative regulations concerning the coal power plants is provided in the theoretical section. The original combustion technology of the granulations boilers prior the modernization and the present state of the fluidized bed combustion technology after it are described. Differences and specifications of the stated technologies are explained in the practical section. The impact of modernization from the environmental criteria point of view with production comparison of polluting emissions during fluidized bed combustion of coal and biomass is analyzed. The economic criteria of modernization on the emission fee calculations bases during fluidized bed combustion of coal and biomass are calculated too. The main differences in combusting the mentioned fuels are explained. The further possibilities of the solid fuel combustion technology in fluidized bed combustor at Poříčí power plant are discussed.
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