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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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Non-energy Applications of Lignite
Majzlíková, Petra ; Maršálek, Roman (referee) ; Janoš, Pavel (referee) ; Pekař, Miloslav (advisor)
This thesis deals with various physical-chemical aspects of agricultural and environmental applications of the South Moravian lignite. The main attention was paid to the behavior of lignite in an aqueous environment and the application potential of lignite as a cheap, effective and universal sorbent. In the experimental part of the thesis, aqueous extracts of lignite were characterized in detail (by measurement of pH, conductivity, and by the qualitative and quantitative determination of inorganic constituents). The high sorption affinity towards polar (cationic dyes) and nonpolar compounds (petroleum products) was confirmed experimentally. At last, simple methods of the laboratory preparation of lignite granules was designed and optimized. The main aim of this part was to combine the unusual sorption properties of lignite with an improvement of the end-use properties of the product (user-friendly handling, controlled release of the lignite into the aqueous environment, etc.). The thesis represents a complex compilation of the results of pilot experiments which represent the starting point of detailed future works focused on the non-energetic application of this valuable natural material.
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Possibilities of utilization of boiler slag
Fialová, Gabriela ; Másilko, Jiří (referee) ; Opravil, Tomáš (advisor)
This bachelor thesis studies the boiler slag (slag) and its potential use in refractory materials industry. It concentrates its on chemical and mineral composition. Mullite parts and Fe2O3 probably lowers the melting point and heat resistance. During the work is proposed and experimentally validated a method for reducing the content of iron in the slag shares.Is observed the effect of the reduced number of iron units for the heat resistance of the material. The results are further processed and assessment. Thermal resistance was monitored using incandescent microscopy.
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Dexterity, or build your house
Netrefová, Klára ; MA, Klára Zahradníčková, (referee) ; Kristek, Jan (advisor)
The design of anthropoid / metamorphosis loosely follows the pre-diploma project Fortel or so called "build a house" when I decided to "put my hand to the work, cut, drill, fold…" and to rediscover the imprints of work and tools in the mass from which they disappeared due to the mass production. The output of the project was an eclectic, crumbling garden of prefabricated bricks. Capillary (open) porosity usually occurs in brick products. It allows the penetration and retention of a relatively large amount of water. The bricks are made of natural mineral raw materials, as well as expanded clay, which is commonly used as a hydroponic substrate. At the same time, the porosity of the brick blocks causes future degradation of the material in the exterior. The disrupted "worked" ceramic blocks in the garden burst, mix with the substrate and create a breeding ground for plants. In my diploma thesis I move away from materials formed into modules, imported to the construction site, and I deal with matter in its freest fluid form and forms arising in-situ. The work is permeated by three fluid media, water, clay and concrete. Concrete - initially a fluid material, takes the form of two other materials, solidifies. Clay - as a semi-solid - semi-fluid material Water - infinitely fluid material, still present, rapidly transforms, and periodically comes and disappears, transforms the other two materials. The materials mix together, form into matter, then drain and disintegrate and disappear when their time comes. With these nature-friendly processes, the design works on three scales. On a micro scale, matter decomposes into gravel, sand, loess, which nourishes soils and plants, and allows an environment suitable for a variety of animals. In the middle scale, these are small objects that shape and manipulate the landscape. And in a big scale, it is co-working with the landscape itself.
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Kaoline whitness improvement by mechano-chemical treatment
Uher, Samuel ; Bartoníčková, Eva (referee) ; Šoukal, František (advisor)
The thesis deals with the issue of increasing the whiteness of kaolin by acid leaching simultaneously with milling. Kaolin was prepared from kaolin raw material from the Otovice quarry (Sedlecký kaolin a.s.), which was subsequently grined in suspension with oxalic acid, tartaric acid or citric acid in a ball planetary mill. We had been observing the influence of the type and concentration of acid and grinding time on many aspects, such as: the whiteness index, the amount of leached Fe and Ti, the distribution of Fe and Ti in kaolin, and the kaolin structure order.
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Usage of Solders with Higher Melting Point for Hybrid Integrated Circuits
Janda, Ondřej ; Jankovský, Jaroslav (referee) ; Otáhal, Alexandr (advisor)
Bachelor thesis introduces the problematics of soldering, explains basic phenomena and principles affecting brazing and points out their positive and negative outcomes, as well as trying to suggest solutions to those negative symptoms accompanying the brazing. Practical part describes a design procedure of the test substrates, methodology of mechanical tests and optimalization of brazing process. As a part of the research, a design and construction of a various brazing tools with heat transfer through a conduit, is included.
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Recycling of steel-works flue dusts from electric arc and inductive furnaces
Huczala, Vít ; Koplík, Jan (referee) ; Šoukal, František (advisor)
This bachelor thesis deals with an application of electric arc furnace dust from steel production as secondary raw material for production of zinc and industrially process able zinc products. In this thesis the dust was processed by methods based on various physical and chemical properties. The most experiments were performed during the treatment with leaching in sulphuric acid. For this leaching the optimal concentration of sulphuric acid and the optimal ratio acid:dust was determined. The final products were prepared by precipitation or by evaporation of filtrate obtained after leaching. There were also used hydrolysis of dust and oxidative precipitation of filtrate during the processing. These steps led to increase of the quality of the final products. The price balance was also performed for the prepared products.
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Conductive net designing for thick film circuits
Strejček, Jindřich ; Řezníček, Michal (referee) ; Jankovský, Jaroslav (advisor)
Bachelor’s thesis was intent on determination the current rating thick film circuits. Describes an intelligent current source with voltage measurement function and its control. Contains a description of testing to test the test structure and processing of its results. From the evidence in trial testing was formed a new test structure, which was used for testing the current rating thic film conductors. Also copper conductors testing was performed. From measured values were drawed the graphs which represents current rating coductors in depend on width and temperature change of conductor.
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Development of the material for solidification based on carbonation of waste materials
Mikulová, Mária ; Koplík, Jan (referee) ; Másilko, Jiří (advisor)
The aim of this thesis was to create a material by solidification of waste materials from steel production. Ladle furnace slag (LFS) pre-treated by demetallization was used as a binder, Fe sludge and a mixture of slags and debris (MSD) coming from Třinecké železárny were used as fillers. The binding properties of LFS are the result of a high content of calcium silicates, which are able to react with CO2 and thus create carbonates, mainly calcite (CaCO3), which act as a binder – this process is called carbonation. Firstly, an effect of substitution of LFS by individual fillers on compressive strength of carbonated testing samples was examined. Based on these results, three solidified materials were proposed, of which compressive strength immediately after carbonation and after 28 days was observed. Leaching behaviour, weight gain of the samples after carbonation, their mineralogical composition, and carbon content were examined as well. Compressive strength of all three solidified materials raised above required 10 MPa after 28 days. Pure carbonated LFS was used and analysed as a reference sample.
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Possibilities of the hydrometallurgical process for the recovery of light metals
Skalík, Martin ; Ptáček, Petr (referee) ; Opravil, Tomáš (advisor)
This bachelor thesis focuses on the assembly of individual stages of the hydrometallurgical process for recovery of lithium, magnesium and aluminum from mica. The main focus was the primary process of hydrometallurgy, i.e. leaching of mica in order to obtain an leachate enriched with lithium, magnesium and aluminum ions. The concentration of metal ions in the leachate was assessed by F-AAS analysis to determine efficiency of the temperature while leaching, leaching time, leaching agent concentration and calcitantion of the input mica.
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