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Evaluation of technology for the biomass incineration.
Havelková, Pavla ; Máša, Vítězslav (referee) ; Jícha, Jaroslav (advisor)
This bachelor’s thesis is interested in description of the biomass and its utilization as a renewable energy source. The text is specified in the production of the biomass and also an overview of the technologies used in its processing and utilization, which is both energy and non-energy. Then, this thesis deals with the description of the various devices, in which the biomass is processed.
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Determination of organic compounds in biochar produced by microwave torrefaction of biomass
Meindl, Jiří ; Vávrová, Milada (referee) ; Mravcová, Ludmila (advisor)
The thesis is focused on a determination of polycyclic aromatic hydrocarbons (PAHs) contained in dried pelletized sewage sludge and pelletized biochar. Biochars were made in mild conditions by microwave torrefaction of prepared sewage sludge. There were analyzed and quantified the 34 of standardized PAHs compounds in two series. The first serie, also called “Sada 1”, has been aimed at comparison of extraction methods for the chosen sample of sewage sludge and the sample of biochar. In serie “Sada 1”, there were compared efficiencies of chosen type of solvent or solvent mixture by comparison of yields for 34 standardized analytes in a sample of biochar and a sample of sewage sludge. There were compared also to total yields of PAHs and to number of quantified compounds in analyzed samples. The most reliable extraction method has been used for the next analyses of samples in the second serie called “Sada 2”. In Sada 2, there were compared different samples of the same type (e.g. biochar, sludge). The origin of sewage sludge (small or big sewage treatment plant expressed as PE) and used additives (cellulose, chaff, hay) as modificators for torrefaction process were variables for different type of sample. The results of analysis were identification of the most suitable sewage sludge and additive to be used as modificator for microwave torrefaction process. The main goal of correctly chosen sludge and additive was to minimize production of PAH’s during torrefaction and in samples of biochar.
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Behaviour of the Interface of Low Toughness Materials
Halasová, Martina ; Pabst, Willi (referee) ; Tatarko, Peter (referee) ; Fintová, Stanislava (referee) ; Chlup, Zdeněk (advisor)
The work is focused on evaluation of factors influencing behaviour of interface in low toughness ceramic materials reinforced with fibres. The main aim was to characterise processing effects influencing the quality of fibre-matrix interface, with respect to final behaviour of composites at various loading type. The partial goal was to map the possibility of influencing the composite material by choice of matrix material, eventually by change of its processing, leading to change of interfacial properties without need of modification of reinforcement surface. The materials used in studied composites as a matrix were based on thermal transformation of polymer precursors, thus, the resulting materials were characterised in partially as well as in fully pyrolyzed state. Behaviour of interface in cpomposite materials was first evaluated from the global behaviour (i.e., change of mechanical properties) and in chosen representative composites also from the point of local changes in close surrounding of the interface (i.e., microstructure, chemical processes, fracture-mechanic processes, etc.) due to thermal exposition. In experiment were used particularly composite materials prepared by pyrolysis of polysiloxane resins reinforced by basalt fibres or Nextel™720 fibres. With respect to thermal resistance of the reinforcement, the basalt reinforced composites contained only partially pyrolyzed matrix (i.e., to temperature of 800°C), and in composites with Nextel™720 reinforcement was the matrix in form of fully pyrolyzed polymer into ceramic (SiOC). At partial pyrolysis of polysiloxane resin occurs rapid change of behaviour at temperature of 600°C. It was demonstrated, that around this temperature the formed interface with basalt fibre exhibits optimum adhesion/strength, allowing to reach sufficient level of composite strength at acceptable fracture toughness. Above temperature of 750°C occur significant difusion processes in the area of the interface and formation of new crystalline phases in the fibre, what deteriorates the fibre strength, and on the contrary, strengthen the interface cohesion, what leads to degradation of properties of the whole composite. At composite materials determined for high temperatures, reinforced by Nextel™720 fibres, was detected significant resistivity against oxidation caused especially by fully pyrolyzed matrix. As similarly important factor was observed the formation of mullite interphase in surface area of the fibre. Volume changes caused by formation of the interphase, difusional transport of the matter and thermal exposition led to formation of thermally and stress-induced micro-cracks, weakening interfacial surrounding in matrix as well as in fibre. This mechanism in contrast to amplifying chemical bond between fibre and matrix led to preserving of the composite properties also at high temperatures up to 1500°C. The work also dealed with effects of loading rate, where in contrast to static loading were observed different failure mechanisms. Realized research led to description and explanation of the influence of the fibre-matrix interface by change of matrix material processing parameters, which allow processing of economically advantageous and thermally stable composite.
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Inorganic analysis of microwave pyrolysis products from sewage sludge
Šintajová, Kristína ; Doležalová Weissmannová, Helena (referee) ; Komendová, Renata (advisor)
This bachelor thesis deals with the analysis of risk elements found in the sewage sludge of wastewater treatment plants and the issue of contamination caused by sludge deposition in soils. Extractions of sewage sludge samples before and after pyrolysis treatment were implemented according to the sequential extraction of BCR and also using aqueous leaching. The determination of the selected element was performed on an atomic absorption spectrometer. A literature research on the use of modified sewage sludge after pyrolysis to increase fertility, improve soil properties and improve their quality was also processed.
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Energetic use of wastewater sludge and microwave pyrolysis products
Šimek, Radim ; Ševčík, Jan (referee) ; Hlavínek, Petr (advisor)
The diploma thesis is focused on the energy utilization of sewage sludge before and after microwave pyrolysis process. The first part of the thesis deals with sludge management, treatment of sludge and its subsequent use or disposal. In the second part of the thesis prepared and modified samples of sludge from WWTP 1 and WWTP 2 are subjected to microwave pyrolysis process. Subsequently, samples are taken for analyzes to determine the total organic carbon, the specific surface area, the heavy metal content and the calorific values. The resulting data was processed in Microsoft Office Excel and presented at work. At the end of the thesis two case studies are then proposed for a specific design of the conceptual location of microwave pyrolysis for the sludge drying process and the drying process of the sewage sludge in the direct combustion boiler room.
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Mineral wool and binding agent interaction and behavior study
Fiala, Michal ; Šoukal, František (referee) ; Ptáček, Petr (advisor)
Diploma's thesis describes resolution of cause technological problems in mineral wool manufacturig in company Saint-Gobain Orsil. Main attention is paid to thermal and volatile process in mineral wool from filtration chamber and common commercial sales. Samples of mineral wool were characterizated by thermal analysis (simultaneous TG-DTA), effluent gas analysis (EGA), infrared spectroscopy (FT-IR), electron microscopy (SEM) and X-ray diffraction (XRD). Thermal analysis experiments was used to check thermal volatile processes. Technological problem of burning is linked with rise of isocyanic acid.
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Experimental reactors for combustion of biomass and municipal solid waste
Bialožyt, Michal ; Juřena, Tomáš (referee) ; Recman, Milan (advisor)
The main purpose of this thesis is background research about experimental reactors for combustion process research. Mainly semted on reactors with fixed bed for alternative fuels, such as biomass and municipal solid waste. Mathematical modeling of the combustion process with modern software products and its optimalization is not possible without input data gathering from these facilities. Thesis should serve as a source of information for building a new experimental reactor.
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Synthetic fuels
Pitoňák, Adam ; Kučera, Pavel (referee) ; Píštěk, Václav (advisor)
The bachelor’s thesis on the topic “Synthetic fuels” aims to introduce the reader to the issue of synthetic fuels and the possibilities of their application for internal combustion engines as alternatives to the conventional fuels derived from fossil sources. The first part of the work is focused on the introduction and division of synthetic fuels according to primary raw material. Subsequently, the properties of the fuels are compared with commonly used fossil fuels. The thesis also deals with the comparison of the equivalents of the emissions of individual synthetic fuels per unit of thermal energy supplied to the engine. Thanks to the model presented in the thesis, it is possible to compare the amount of CO2 equivalent per driven kilometre. The conclusion of this work summarizes the result of the comparison of synthetic fuels with prospects of such fuel in the future.
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Utilization of biodegradable waste
Švec, Jan ; Pěček, Jan (referee) ; Beňo, Zdeněk (advisor)
The aim of this paper is to summarize the current situation of the problem using biodegradable waste. The introductory chapters deal with descriptions of different types of biodegradable waste. The main part describes ways of handling this waste. For various types of waste are listed by their most appropriate treatment and further use. Emphasis is placed on legislation dealing with that waste legislation on the processing equipment.
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Recyclation of Plastics
Lasota, Ondřej ; Němec, Karel (referee) ; Molliková, Eva (advisor)
Plastic materials thanks to their properties like strength, durability, versatility and relatively low cost has gained this much popularity. With their constantly increasing amounts contribute to the waste. Most frequent method of waste disposal is landfill, which is due to plastic’s durability undesirable and causes serious problem for the environment. This bachelor thesis focuses on the use of secondary raw materials obtained from polymer waste. Large amounts of generated polymer waste can be appropriately designed methods processed to produce fuel, to modify asphalt mix and to reinforce concrete. Different methods are analyzed and their advantages and disadvantages are shown.
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