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Utilisation of already deposited energy by-products in cement production
Lukášek, David ; Švec, Jiří (referee) ; Opravil, Tomáš (advisor)
This bachelor thesis focuses at study of deposited high-temperatured fly ash and its utilization in production of cement. The theoretical part of the bachelor thesis deals with the production and division of cements. The individual advantages and disadvantages of high-temperature and fluid fly ash when added to cements are addressed. The theoretical knowledge was used to design subsequent experiments. The conclusion of the theoretical part of the work deals with pozzolans. The main content of the experimental part was the analysis of raw materials and subsequent analysis of the mechanical properties of the prepared mixtures. The experiments were designed in accordance with valid standards.
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Effect of ground limestone addition on properties of cement-slag binder systems
Bílek, Vlastimil ; Másilko, Jiří (referee) ; Opravil, Tomáš (advisor)
This thesis deals with the effect of ground limestone addition on properties of cement-slag binder system. The evolution of compressive and flexural strength of binary and ternary systems (pastes), where 25 % of cement was substituted by one or two admixtures in different ratio, were determined and mutually compared. Granulated blast furnace slag and three different limestones were these admixtures. Two of that limestones were natural and one was prepared by a precipitation. For comparison, mixtures, where ash was added insted of slag, were prepared. The mechanism, by which finely ground limestone participates in hydration process, was studied by conduductometric measurements of systems simulating conditions in fresh pastes, and by TG-DTA method, which was used to determination of added limestone amount which remains in its original form and the amount which participates in the formation of hydration products.
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Possibilities of using yet unused secondary products from the production of titanium white
Smirnov, Pavel ; Másilko, Jiří (referee) ; Opravil, Tomáš (advisor)
Waste products are an integral part of any production. The production of titanium white is no exception. The bachelor thesis is aimed at finding an application for a secondary product, red chemogypsum which is obtained by neutralizing waste sulfate water. The thesis aimed to find a suitable application for chemogypsum in the construction industry using experiments. The calcium sulfate dihydrate was processed by drying into monohydrate, which is the basic raw material of many products. Furthermore, the composition of the material was determined. Its properties such as onset of solidification, compressive and flexural tensile strength were investigated. Gypsum plasterboards and lightweight and insulating boards were also made. This binder was also used in filling bricks with inorganic insulating material. The knowledge gained from this work can be used to further research and improve products and hopefully make realistic use of this hitherto deposited material in the future. The thesis also provides concrete examples and suggestions for the use of this secondary raw material.
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Possibilities of using of fluid fly ash in the self-leveling systems
Zárybnická, Klára ; Bílek, Vlastimil (referee) ; Opravil, Tomáš (advisor)
The work deals with the study of possibilities of using fluid ashes in self-leveling floor systems. The task of this work is to reach a proper composition of self-leveling floor mixture with high capacity of fluid ash in binding compoment, which means replacement of portland cement primary. In the work there are monitored mechanical and durable properties of tested self-leveling systems, which are evaluated according to valid norm. Especially the work is focused on volume changes during hydratation and maturation of new designed self-leveling systems, because thanks to high capacity of free lime and anhydrite in fluid ashes there are volume changes thanks to formation of ettringite.
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Possibilities of using waste diatomaceous earth
Jonešová, Markéta ; Másilko, Jiří (referee) ; Opravil, Tomáš (advisor)
Waste diatomaceous earth is a by-product generated during a production of diatomaceous earth for filtration. It is a material with very specific properties, which has currently no use other than backfilling of mining areas. For this reason, this Bachelor thesis deals with exploration of potential utilization possibilities of this remarkable material. Analysis of the waste diatomaceous earth will be carried out, and the chemical and physical properties will be determined. During experimental part, a set of calcination tests will be carried out and evaluated with focus on properties of the waste diatomaceous earth, which could be significantly increased by the calcination process. For example, a pozzolanic activity could be significantly affected.
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Industrial sludges as alternative fuel in cement plant
Raška, Miroslav ; Kalina, Lukáš (referee) ; Opravil, Tomáš (advisor)
This thesis deals with the use of industrial sludge as an additive to alternative fuels in the cement industry. The first part is focused on solid alternative fuels, especially sewagesludge, processed and used in the firing process of Portland clinker and heatingpotential of the secondary raw materials, fuels. The second part deals with the history, production of cement and its raw material base. The last part contains information of practical measurements and draw conclusions about the appropriateness of using that type of industrial sludge in cement as a solid alternative fuel.
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Preparation of historical binders with high resistance to ambient influences
Nehybka, Josef ; Palovčík, Jakub (referee) ; Opravil, Tomáš (advisor)
This master’s thesis is focused on preparation of the mortar mixtures inspired by roman cement with a great resistivity against the corrosion environment, especially a seawater. There were prepared samples of a roman cement containing of pure lime and various artificial pozzolans and natural tuff which were used as pozzolan admixtures. The task of this work is to explore possibility of using pure lime and for example pozzolan admixture which can resist against the corrosive environment like a roman cement. There were prepared a lot of various samples which were tested separately on their mechanical characteristics before and after their exposure of the influence of the corrosive environment. There were used X-ray diffraction analysis for the characterization of a phase composition of the raw materials and some selected samples.
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The optimization of phosphate binders compozition used for refractories
Kalousová, Hana ; Ptáček, Petr (referee) ; Opravil, Tomáš (advisor)
This thesis deals with optimization of the composition phosphate binders. These binders are used in production of refractories. In this branch, the bauxite is very often used as an aggregate, but it contains tiny particles of iron which arise in milling process. These particles of iron react with the phosphate binder to form hydrogen – it is consequence of the reaction between phosphoric acid and iron. The formed gas causes the formation of bubbles and the deformation of refractories. The goal of this thesis is to find suitable additives which can be used to stop or to limit the production of hydrogen. Usually used binders were replaced by a model binder to simplify the system and for better understanding. The model binder was prepared in laboratory by dissolving aluminium hydroxide in phosphoric acid. They used pure powdered pentacarbonyl iron instead of tiny iron particles from the milling process. The model binder was modified with using a few inhibitors. The calcimetr was used to measure their influence on the production of hydrogen, as well as measuring concentrated rows of selected inhibitors. These rows are necessary to optimize the inhibitors quantity added in the binder.
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Possibilities of application of phosphate bond in brick abrasion dust treatment
Tmejová, Jana ; Havlica, Jaromír (referee) ; Opravil, Tomáš (advisor)
This bachelor´s thesis deals with possibilities of application of phosphate bond in brick abrasion dust treatment. Brick abrasion dust is produced as a secondary product of brick production during brick grinding. Brick abrasion dust is a relatively fine powder of the same composition as a burnt brick fragment. Since the brick abrasion contains an insufficient amount of the aluminum component, which is crucial for the formation of phosphate bond, the work is primarily concerned with finding a suitable aluminum dopant. The aim of the thesis is to find a suitable admixture that has a sufficient content of aluminum to form a phosphate bond and to determine the ideal amount to be added. Alternative sources of the aluminum component are tested in combination with a commercially available phosphate bond (Alufos 50).
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