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Biochar effect on distribution of organic matter in soil
Haleš, Petr ; Širůček, David (referee) ; Kalina, Michal (advisor)
Biochar is a carbon-rich material that can be used in agronomy as a soil conditioner. The selection of the source biomass and the conditions used during pyrolysis (for example residence time and temperature) can have different effect on the physicochemical properties of this material. In this bachelor thesis biochar was produced from oat bran, woodchips, corn and compost by pyrolysis at 600 °C. The woodchips were also pyrolysed at temperatures in the range 400–700 °C. These biochar samples were subsequently leached with model rainwater. The main aim of this thesis was to assess how the conditions of biochar production influence the quantity and nature of substances, which can be released from this material. In the second part of this thesis, the commercial biochar Agrouhel (produced from sewage sludge at temperature 450–470 °C) was used (“Káňa”). This biochar was leached with model rainwater and dilute solutions of citric acid (which simulates root exudates) and hydrogen peroxide (which simulates enzymatic biochar degradation). Physicochemical characterization (pH and conductivity) of the extracts was realized after each leaching cycle. Additional analyses (UV-VIS and ICP-OES) of the solution were measured after the 1st, 5th and 10th cycle. The original solid biochar and biochar samples after the 10th cycle of leaching were used to determine the inorganic and organic fractions and to determine the elemental composition of the organic fraction (TGA and EA). The laboratory cultivation experiment with biochar Káňa was performed on the model plant (Lactuca sativa). Biochar obtained after termination of the cultivation was analysed (pH, conductivity, ICP-OES, TGA and EA) and the results were compared with data obtained for biochar Káňa leached by different model solutions. Fulvic and humic acids were extracted from the original biochar Káňa as well as from the biochar obtained after the termination of cultivation experiment. These samples were analysed on their inorganic and organic content and the abundance of organic elements (TGA and EA). Afterwards, the results were compared to each other and the correlations between the laboratory exposure to each soil factor and the cumulative exposure during the soil culture experiment were assessed.
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Study of adsorption of organic pollutants on wheat bran biochar
Hanák, Jan ; Pořízka, Jaromír (referee) ; Diviš, Pavel (advisor)
This diploma thesis explores the application of the Diffusive Gradients in Thin Films (DGT) method for determining and monitoring the concentrations of dissolved pharmaceuticals and organic dyes in water and food. The theoretical part introduces the issue of the occurrence of these organic substances in water and food, the principles of the DGT method, the characteristics of adsorption and adsorption isotherms, and the introduction of biochar as an adsorbent. The experimental section primarily focuses on optimizing and validating adsorption gels containing commercial biochar and unmodified biochar from wheat bran for the adsorption of specific substances using the DGT method. Oxytetracycline was primarily tested from a selection of antibiotics and malachite green from organic dyes, which is widely used in aquaristics. The results demonstrate a comparison of the effectiveness of adsorption using these two types of adsorbents and their characteristics, such as infrared spectroscopy analysis or images from a scanning electron microscope. From the Langmuir isotherm, the maximum adsorption capacity for oxytetracycline on commercial biochar was found to be 314,065 mgg-1 and the maximum adsorption capacity for wheat bran biochar was 89,720 mgg-1. The maximum adsorption capacity of commercial biochar for malachite green was 439,406 mgg-1. The work further emphasizes the potential of the DGT method as a tool for food analysis and investigating contaminants in water systems, which further move into the food chain.
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Analysis of organic compounds in the soil-biochar-salad system
Hlaváčová, Josefína ; Řezáčová, Veronika (referee) ; Mravcová, Ludmila (advisor)
The bachelor’s thesis presented focuses on the analysis of polycyclic aromatic hydrocarbons extracted from lettuce, soil, biochar and soil mixed with biochar. Polycyclic aromatic hydrocarbons are introduced into the biochar during the production process, i.e., pyrolysis. After applying the biochar to the soil, the polycyclic aromatic hydrocarbons can be released into the soil and contaminate it. The theoretical part of the thesis focuses on the production and characterisation of biochar, its applications to the soil and subsequent changes it induces within the soil. The experimental part focuses on the optimization of the microwave-assisted extraction process. Furthermore, experiments were carried out, assessing the influence of the added biochar on the concentration of polycyclic aromatic hydrocarbons within soil and lettuce. The sample analysis included microwave-assisted extraction and quantitative and qualitative determination using GC/MS/MS. The samples analysed were assessed for the presence and concentration of 16 different polycyclic aromatic hydrocarbons, prioritised by the U.S. Environmental Protection Agency. The analysis of the samples of lettuce grown in the soil containing biochar display a higher concentration of polycyclic aromatic hydrocarbons compared to samples without biochar. The analysis of the lettuce roots showed identical results.
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Preprocessing of sewage sludge for pyrolysis process
Ševčík, Jan ; Rusník,, Igor (referee) ; Bodík,, Igor (referee) ; Hlavínek, Petr (advisor)
The concept of sludge management at the level of sludge treating technology of sewage treatment plants, as well as at national, continental or world level, requires fundamental improvement in the interest of sustainable development. Sewage sludge production is continuously increasing. Sewage sludge contains a number of pollutants but also a significant renewable resource for material transformation and / or energy recovery. Sewage sludge is composed of an inorganic mineral part and organic components. Its organic part is a source of energy and nutrients, but also contains harmful pollutants for exapmple heavy metals. However, there are technologies that offer the possibility of neutralizing pollutants while using other sludge components in terms of recycling energy, nutrients and other attractive sludge components. The mentioned technologies include mainly thermal methods of sewage sludge treatment and one of them is pyrolysis. Thessis focuses on sewage sludge prepartation for pyrolysis process, which includes mixing with additives and peletization of prepared mixture for purposes of agricultural or energetical utilisation. Technology for material transformation and energy utilization of sewage sludge, in particular the mentioned pyrolysis or torrefaction, require an insignificant degree of detailed research in order to expand it in the field of sludge management. Indeed, it is not only research that will enable direct correct use of this technology in practice. The results of such research are the basis for the drafting of the relevant legislation, which will subsequently enable the deployment of pyrolysis technologies in practice.
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Determination of content of organic compounds in biochar
Novotná, Martina ; Řezáčová, Veronika (referee) ; Mravcová, Ludmila (advisor)
Biochar is created during the pyrolysis of organic biomass. Once added into the soil, it can improve its features. Biochars made from sewage sludge have various compositions. It is because of the vast difference between entrance materials. Organic pollutants can be absorbed into its surface during the cooling proces sof pyrolysis. If released into the enviroment, these compounds can cause inhibition of plant growth, get into food chains and adversely affect living organisms. Organic pollutans are determined most often by GC/MS after organic solvent extraction.
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Influence of pH on Extraction of Matter from Biochar-Soil Complex
Jakubčeková, Kristína ; Enev, Vojtěch (referee) ; Kalina, Michal (advisor)
Biochar is one of the possible solutions to improve the soil fertility, therefore it is necessary to investigate both its composition and the impact on the soil under various conditions. The aim of this bachelor thesis is to focus on the description of the influence of pH on the amount and type of substances (molecules, ions) that are leached from the biochar into the soil and thus consequently influence its properties. As a soil model it was chosen cambisol which is the most widespread soil in the Czech Republic. The selected pH values have been defined in such a way to cover the pH range that is common for various soil types in natural conditions. In the experimental part of this thesis the extracts from the used sample of biochar and soil were characterized first. These characteristics obtained in this way were subsequently compared with the data obtained for the biochar-soil complex extracts that was obtained after a defined period of cultivation of the mixture. For the characterization of extracts the basic physico-chemical methods (pH, conductivity, elemental and thermogravimetric analysis, UV-VIS) and also the analysis of leached ions and molecules by means of ICP/OES, GC-MS were used. Evaluated experimental data show that under the condition of cultivation experiments, the influence of biochar was observed only on the basic physico-chemical characteristics of the soil (mainly pH). On the other hand, there was no significant tendency of the impact of biochar on the representation of selected elements and on the content of organic matter in the soil. Long-term biochar-soil cultivation experiments could be a suitable solution.
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Preparation and basic chemical and physical characterization of biochar from wheat bran
Zouharová, Kamila ; Diviš, Pavel (referee) ; Pořízka, Jaromír (advisor)
At present, the extraction of biochar and its use is a much-discussed topic in the chemical and research fields. The use of biochar is very often declined in the areas of agriculture, waste management, environmental improvement and the fight against global warming. In addition to these sectors, the topic of biochar is also addressed in the production of bio-diesel and bio-oil. Due to the current use of secondary products during biotechnological processes, the presented theoretical and practical study focused on the issue of obtaining biochar from bran by pyrolysis at different temperatures. Part of the practical part was the extraction of biochar from bran and its subsequent analysis, which could be used to characterize biochar obtained from bran by pyrolysis physically and chemically. The characterization of bran biochar was solved by various analytical methods. These techniques yielded, for example, pH, conductivity, particle distribution, elemental composition of biochar, porosity and content of polycyclic aromatic hydrocarbons. Thanks to this study, the properties of biochar and its possible applications in everyday life were characterized in detail. Given the very promising use of biochar obtained from bran, it can be said that this will be a very desirable topic for the future.
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Ecotoxicological Assessment of Point Pollution in the Ecosystem
Doležalová, Šárka ; Beklová, Miroslava (referee) ; Kráčmar, Stanislav (referee) ; Koutný, Marek (referee) ; Vávrová, Milada (advisor)
The main subject of this dissertation is the ecotoxicological evaluation of significant point sources of pollution. These include wildfires and wide fires of factories and also industrial and urban wastewater treatment plants. The local application of pyrolytic product obtained from sewage sludge as the point source of pollution was also included in the thesis. Tests in aquatic and contact arrangement with using both water and soil organisms for ecotoxicity evaluation of selected matrices were chosen. Crustaceans Thamnocephalus platyurus, Daphnia magna Straus and sea bacteria Vibrio fischeri were selected as representative organisms of water animals. Duckweed Lemna minor was chosen as water plant. Further collembola Folsomia candida and earthworm Eisenia fetida were chosen as representatives of soil animals. Finally onion Allium cepa L. and mustard Sinapis alba are representatives of terrestrial plants. Submitted thesis deals about analytes of interest, their properties and ways of distribution to the environments. The output of the thesis is a comprehensive assessment of the effects of selected point sources of pollution on aquatic and terrestrial ecosystems organisms and ecotoxicological risks assessment. The fire extinguishing agents have been proven to be the most stressful substances for all selecteded organisms.
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The use of biochar as a sorption material for the removal of synthetic fragrances from water
Kašparová, Jarmila ; Zlámalová Gargošová, Helena (referee) ; Mravcová, Ludmila (advisor)
Synthetic fragrances (musk) are artificially produced organic compounds. It is used as fragrance ingredient in personal care products. Substances from this group have the ability to withstand the cleaning process in wastewater treatment plants. The physico-chemical properties of musk compounds cause their accumulation in the living and non-living components of the ecosystem, where they behave as persistent pollutants. The adsorption process is considered to be one of the most widely used separation and purification processes. The adsorption processes of a solution of sixteen synthetic fragrances took place with biochar and activated carbon. Solid phase microextraction (SPME) was used as a method for extracting analytes. Gas chromatography coupled with mass spectrometry (GC-MS) was applied for final analysis, time of flight analyzer was used as detector. The data were fitted with adsorption isotherms.
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Removal of micropollutants from wastewater by adsorbtion.
Trávníček, Jakub ; Macsek, Tomáš (referee) ; Hlavínek, Petr (advisor)
The aim of the thesis is to create a research on the issue of adsorption of micropolutants with a subsequent focus on biochar. The first part therefore deals with the micropolutants themselves, the origin of their formation in wastewater and their negative impact on the health of organisms. It also deals with adsorption technology, discusses its basic knowledge necessary to grasp the topic and describes known adsorbents and their use. It pays special attention to biochar. The second part of the thesis deals with practical filter tests of adsorption abilities of biochar on wastewater from tunnel maintenance and treatment carried out in the laboratory of the AdMaS centre.
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