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Utilization possibilities of industry gypsum and secondary materials containing for preparation of composites
Weiglová, Jana ; Šoukal, František (referee) ; Opravil, Tomáš (advisor)
The work studies the possibilities of the utilization of secondary raw materials produced by power industry. It addresses mainly the gypsum by-products and fluidized coal combustion ash. As for the secondary raw materials the content of sulphites is observed and the dependences of their transformation to sulphides via natural oxidation by air oxygen or by addition of adequate oxidant are studied. The work follows with describing the effect of sulphides contained in raw materials on the mechanical properties of composites prepared from several various matrices such as alumina or portland cement, lime or portland clinker. As for pure portland clinker the ability to retard the setting is also observed. The amount of contained sulphites is measured volumetrically via indirect titration of iodine surplus by sodium thiosulphate with the starch size as the indicator.
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Self-leveling floors based on secondary raw materials
Darakevová, Michaela ; Šiler, Pavel (referee) ; Opravil, Tomáš (advisor)
The work deals with the use of secondary raw materials in the self-leveling floor systems when used as a secondary raw material perform here especially classic ash, boiler slag and gypsum from flue gas. Work is looking for ways in as much as possible to replace conventional materials used in self-leveling flooring systems, secondary energy products. The aim of this work is to determine the optimal amount and ratio of secondary raw materials in self-leveling flooring compounds so that they are maintained or improved standard properties of these compounds reported in the standards. The work is divided into several points, the first point was first sought appropriate composite binder, where it was used as aggregates reach a standard sand. At other points the sand was then replaced by secondary materials. Were also tested ingredients to influence the rate of cooling, or for the onset of the initial strength.
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Supersulphates cements
Mohelská, Lucie ; Wirthová, Michaela (referee) ; Opravil, Tomáš (advisor)
The work is studying posibilities of use secondary materials produced by energetical industry. In fact it studies posibilities of preparing supersulphates cements with secondary raw materials. Its main system for simulation was used milled portland clinker. To clinker were added diferent secondary raw materials from energetical industry with sulphate. On prepared samples were watched mechanical properties in time. Tested were different samples of secondary raw materials.
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Possibilities of clay plasters shrinkage elimination
Melichar, Jindřich ; Koplík, Jan (referee) ; Opravil, Tomáš (advisor)
Earth plasters which are applicated in interiers don´t have just an estetic, but mainly heat storage function. To accomplish better storage properties the plaster has to be laid on the wall in sufficient thick ply. But this use to be accompained by creating of cracks during dehydration of the plaster. This bachelor work will be considering possibilities of elliminating this negative event by additing suitable components to suppress shrinkage and cracks by creating ettringite.
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Volume changes of concrete based on reactive powder components and possibilities of their regulation with chemical admixtures
Hlaváček, Jaroslav ; Kalinová, Helena (referee) ; Opravil, Tomáš (advisor)
Very high strength of RPC allows them to an unusual extreme possibilities of their applications. Volume change (shrinkage) negatively affects their relatively broad range of applications, particularly in applications which are used for filling tubes or other components. In today's advanced time with plenty of chemical ingredients and additives on the market (such as the expansion component) could be a side effect of this largely eliminated, or removed entirely. Only some components of the expansion will be appropriate for RPC cements. This reaserch investigates the expansion of ingredients on the basis of sulfates and monitors not only volume changes, but also the strength characteristics and tolerability of the tested anchors tested with a matrix component of the expansion.
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Gypsum free cements with retarded setting by plastisizer and alkali compond
Sedlařík, Tomáš ; Ptáček, Petr (referee) ; Havlica, Jaromír (advisor)
This thesis deals with preparation of gypsum free cements with retarded solidification. It focuses on their preparation by alkali activation with addition of superplasticizers and without superplasticizers. The main aim of this work is to suggest substitution of gypsum in Portland cement by other materials. Ash after fluidized combustion was chosen as a good compensatory raw material with respect to sustainable development. Milled fluidized bed ash from heating station Třinec was tested. Examined pastes were prepared by alkali activation. 50% solution NaOH and sodium water-glass were used as alkali activators. Trial specimens (20x20x100 mm) were prepared from pastes. Measurements of calorimetric properties of unprocessed pastes tested mixtures were implemented. Bending and compressive strength of pastes were also explored.
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Development of different types of fly ash autoclaved aerated concrete
Bednárik, Vít ; Kulísek,, Karel (referee) ; Drochytka, Rostislav (advisor)
This bachelor´s thesis deals with the current technologies of production and raw materials used in the production of fly ash autoclaved aerated concrete. The choice of suitable materials is an important prerequisite for achieving the desired properties of the finished product. Fly ash autoclaved aerated concrete has become one of the options, how to use fly ash, produced as a secondary raw material in the combustion of coal in heating power plants. This work deals with the comparison the physico - chemical properties of the fly ash in the Czech Republic and the subsequent optimization of the composition of the raw mix for the production of fly ash autoclaved aerated concrete with the maximum use of alternative raw materials.
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The database of waste incinerators in Europe
Šaldová, Lenka ; Ručka,, Jan (referee) ; Hluštík, Petr (advisor)
The aim of this thesis is to describe modern technological processing lines MSW incinerators. Describe individual objects and their links with the principle of thermal combustion. Processes described in the process line will be: waste reception, storage and waste materials, waste pretreatment, loading of waste into the process, thermal treatment of waste, energy utilization and conversion, gas cleaning, disposal of residues from flue gas cleaning, gas discharge, monitoring and control emissions , cleaning and inspection of wastewater treatment and disposal of ash (kiln ash), discharge (disposal) of solid residues. In the second part of this database will be set up incinerators occurring in Europe with basic information (address, website, kiln type, number of lines, the amount of waste incinerated, etc.). The developed database will be created graphs for better clarity and comparison. The database will be accompanied by the emission requirements of individual countries according to the applicable domestic and European legislation.
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