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Comparison of microstructure of standard and modified fly ash autoclaved aerated concrete
Fleischhacker, Ján ; Kulísek, Karel (referee) ; Drochytka, Rostislav (advisor)
Nowadays, the amount of produced fly ash and fluidized ash is huge, so it is important to find ways of its proper use.Significant influence in field of fly ash consumption is production of autoclaved aerated concrete. Most important factor in production is properties of raw materials such as mineralogical and chemical composition. The study of raw materials is important to understand the mechanism of hydratation, tobermorite formation and mineralogy of final product. In present study, we investigate influence of raw materials to mineralogy of autoclaved aerated concrete, significantly to influence of fluidized ash on quality of autoclaved aerated concrete. Closure of study is design of the methodology, specialized in field of bachelor’s thesis study.
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The effect of fly ash aerated concrete production technology to formation of tobermoritic phases
Fleischhacker, Ján ; Kulísek, Karel (referee) ; Drochytka, Rostislav (advisor)
Autoclaved aerated concrete is long-time ecological building material with usefull properties. There needs to be done research of its mineralogical compound for reengineering the production. The main mineral compound of AAC is tobermorite, it increases its mechanical properties. In the presence study, we examine the usage of nature and artificial silicious materials. Also, we investigate the influence of sulfate and alumina admixtures, as well as fluidized bed combustion ash, which can be used as the lime and gypsum replacement. Closure of the study is design of the optimal raw material composition, also hydrothermal treatment of autoclaved aerated concrete. In relation to its mechanical properties, mineralogical composition and cost.
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The usage of the fine aggregates to cement bound mixtures
Švarcová, Monika ; Hýzl, Petr (referee) ; Stehlík, Dušan (advisor)
This bachelor thesis occupies with use of fine aggregates in hydraulically bound mixtures for road pavement bases and sub-bases. The theoretical part describes properties of bound mixtures, aggregates and bound materials. This part also deals with laboratory methods used for bound mixtures and foreign research. In the practical part sand and gravel, crushed stone and recycled fine aggregates are used in bound mixtures with cement or cement and fluidized bed combustion ash. The unconfined compressive strength and frost and water resistance of bound mixtures are tested. The results of laboratory tests are evaluated and compared. The used mixtures are mostly found as suitable for pavement sub-bases.
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Possibilities of utilization of solid residues from fluidized bed combustion for preparation of composite Portland cements
Beranová, Denisa ; Šiler, Pavel (referee) ; Opravil, Tomáš (advisor)
The bachelor thesis deals with possibilities of utilization of solid residues from fluidized bed combustion of coal, bed and filter ash, to be used in the production of composite Portland cements. 6 ash types were investigated, of which 3 were bed ash (finely ground) and 3 were filter ash colected from Ledvice, Tisová and Poříčí K8 power plants. The chemical composition of the ash collected was determined and the progress of a hydration reaction monitored, and then samples mixed with Portland clinker were prepared. Their respective compressive strength and flexural strength were then analysed and observations made on the hydration and composition of products of the hydration reaction. Finally the results of selected mixtures were verified with prepared standardized mortars.
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The usage of the fine aggregates to cement bound mixtures
Švarcová, Monika ; Hýzl, Petr (referee) ; Stehlík, Dušan (advisor)
This bachelor thesis occupies with use of fine aggregates in hydraulically bound mixtures for road pavement bases and sub-bases. The theoretical part describes properties of bound mixtures, aggregates and bound materials. This part also deals with laboratory methods used for bound mixtures and foreign research. In the practical part sand and gravel, crushed stone and recycled fine aggregates are used in bound mixtures with cement or cement and fluidized bed combustion ash. The unconfined compressive strength and frost and water resistance of bound mixtures are tested. The results of laboratory tests are evaluated and compared. The used mixtures are mostly found as suitable for pavement sub-bases.
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The effect of fly ash aerated concrete production technology to formation of tobermoritic phases
Fleischhacker, Ján ; Kulísek, Karel (referee) ; Drochytka, Rostislav (advisor)
Autoclaved aerated concrete is long-time ecological building material with usefull properties. There needs to be done research of its mineralogical compound for reengineering the production. The main mineral compound of AAC is tobermorite, it increases its mechanical properties. In the presence study, we examine the usage of nature and artificial silicious materials. Also, we investigate the influence of sulfate and alumina admixtures, as well as fluidized bed combustion ash, which can be used as the lime and gypsum replacement. Closure of the study is design of the optimal raw material composition, also hydrothermal treatment of autoclaved aerated concrete. In relation to its mechanical properties, mineralogical composition and cost.
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Possibilities of using of energy by-products as raw materials for hydrothermal reaction
Galvánková, Lucie ; Koplík, Jan (referee) ; Opravil, Tomáš (advisor)
The aim of this master thesis is study of possibilities of processing energy by-products, especially coal fly ash and fluidized bed ash, by hydrothermal treatment. Thanks to hydrothermal conditions and proper alkali activation of ashes we can obtain zeolites. Zeolites are microporous crystalline aluminosilicates which are use in many industrial sectors as catalysts, adsorbents and very good ion exchangers. The results of hydrothermal synthesis are influenced by many variable factors. This thesis mainly focused on influence of chosen alkali activator and the concentration of the activator together with a temperature of hydrothermal process. Other factor that is studied is choice of starting materials and solution/ash ratio. Phase composition of prepared samples was characterized by XRD and scanning electron microscopy (SEM). Also cation exchange capacity of prepared samples was determined.
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Possibilities of utilization of solid residues from fluidized bed combustion for preparation of composite Portland cements
Beranová, Denisa ; Šiler, Pavel (referee) ; Opravil, Tomáš (advisor)
The bachelor thesis deals with possibilities of utilization of solid residues from fluidized bed combustion of coal, bed and filter ash, to be used in the production of composite Portland cements. 6 ash types were investigated, of which 3 were bed ash (finely ground) and 3 were filter ash colected from Ledvice, Tisová and Poříčí K8 power plants. The chemical composition of the ash collected was determined and the progress of a hydration reaction monitored, and then samples mixed with Portland clinker were prepared. Their respective compressive strength and flexural strength were then analysed and observations made on the hydration and composition of products of the hydration reaction. Finally the results of selected mixtures were verified with prepared standardized mortars.
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Comparison of microstructure of standard and modified fly ash autoclaved aerated concrete
Fleischhacker, Ján ; Kulísek, Karel (referee) ; Drochytka, Rostislav (advisor)
Nowadays, the amount of produced fly ash and fluidized ash is huge, so it is important to find ways of its proper use.Significant influence in field of fly ash consumption is production of autoclaved aerated concrete. Most important factor in production is properties of raw materials such as mineralogical and chemical composition. The study of raw materials is important to understand the mechanism of hydratation, tobermorite formation and mineralogy of final product. In present study, we investigate influence of raw materials to mineralogy of autoclaved aerated concrete, significantly to influence of fluidized ash on quality of autoclaved aerated concrete. Closure of study is design of the methodology, specialized in field of bachelor’s thesis study.
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