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Changes of slag particles during its alkaline activation
Petrů, Ludmila ; Hrubý, Petr (referee) ; Bílek, Vlastimil (advisor)
This bachelor thesis deals with changes of slag particles during its alkaline activation. The altered parts of the slag as well as the course of the alkaline activation varies depending on the activator used, and therefore suspensions of blast furnace slag in sodium hydroxide, water glass, sodium carbonate and, for comparison, in water were prepared. Slag particles were isolated from these suspensions at selected time intervals (5 min, 30 min, 1 h, 2 h, 5 h and 24 h) for particle size analysis and evaluation of BET specific surface. After solidification, the microstructure of the samples was observed using an electron microscope. To better assess the reaction processes, the pore solution was isolated from the suspensions and its composition was analyzed using optical emission spectrometry in inductively coupled plasma. The hydration process was monitored using isothermal calorimetry.
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Effect of curing conditions on the properties of alkali activated slag
Rypák, Peter ; Bayer, Patrik (referee) ; Rovnaník, Pavel (advisor)
Combination of fine ground granulated slag with proper alkaline activator gives alkali-activated slag – a material with remarkable properties. Theoretical part of the thesis deals with summarizing basic informations about alkali-activated slag, its properties, production and utilization. It also follows research devoted to effects of curing of alkali activated slag and shrinkage-reducing admixtures on its properties. Objective of the experimental part is to determine the influence of curing conditions on the mechanical properties and microstructure of alkali-activated slag. These properties are also monitored in alkali-activated slag with carbon nanotubes and hydroxypropylmethylcellulose as an shrinkage-reducing admixtures.
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The influence of alkali activator on immobilization of metals in alkali activated blast furnace slag
Bystrianska, Emília ; Kalina, Lukáš (referee) ; Koplík, Jan (advisor)
In this work the influence of alkaline activator on immobilization of lead and copper in alkali-activated blast furnace slag was investigated. A total of five activators were used; sodium water glass, potassium water glass, sodium hydroxide, potassium hydroxide and sodium carbonate. The leaching test according to ČSN EN 12457-4 was used to evaluate the level of immobilization of heavy metals, the leached solutions were analyzed by ICP-OES. For a better understanding of immobilization, the selected samples were characterized by analytical methods (FTIR, XRD, SEM, XPS). It was found that the degree of immobilization Pb2+ and Cu2+ in AAS was very high, regardless of the type of alkaline activator used.
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Effect of moisture on the electrical properties of silicate composites
Karlíková, Helena ; Kusák, Ivo (referee) ; Rovnaník, Pavel (advisor)
This work deals with study on the dependence of electrical properties on the moisture content in silicate composites. The theoretical part contains information about the electrical properties of cement-based and alkali-activated binders, as well as knowledge on moisture parameters and the presence of moisture in the material structure. Samples of cement-based mortars and alkali-activated slag with a graphite powder in the range of 0–18 per cent by weight were produced and quartz sand was used as filler in the experimental part. The samples were provided with copper electrodes and saturated with water after hardening. The electrical properties of the mortars were monitored by means of impedance spectroscopy during the gradual drying of the samples. The effect of microstructure has been studied using scanning electron microscopy and mercury intrusion porosimetry. The results indicate that a significant increase in electrical resistance occurs only when the relative sorption humidity content is below 20 per cent in the 40–5000 Hz frequency range.
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Changes of slag particles during its alkaline activation
Petrů, Ludmila ; Hrubý, Petr (referee) ; Bílek, Vlastimil (advisor)
This bachelor thesis deals with changes of slag particles during its alkaline activation. The altered parts of the slag as well as the course of the alkaline activation varies depending on the activator used, and therefore suspensions of blast furnace slag in sodium hydroxide, water glass, sodium carbonate and, for comparison, in water were prepared. Slag particles were isolated from these suspensions at selected time intervals (5 min, 30 min, 1 h, 2 h, 5 h and 24 h) for particle size analysis and evaluation of BET specific surface. After solidification, the microstructure of the samples was observed using an electron microscope. To better assess the reaction processes, the pore solution was isolated from the suspensions and its composition was analyzed using optical emission spectrometry in inductively coupled plasma. The hydration process was monitored using isothermal calorimetry.
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Effect of moisture on the electrical properties of silicate composites
Karlíková, Helena ; Kusák, Ivo (referee) ; Rovnaník, Pavel (advisor)
This work deals with study on the dependence of electrical properties on the moisture content in silicate composites. The theoretical part contains information about the electrical properties of cement-based and alkali-activated binders, as well as knowledge on moisture parameters and the presence of moisture in the material structure. Samples of cement-based mortars and alkali-activated slag with a graphite powder in the range of 0–18 per cent by weight were produced and quartz sand was used as filler in the experimental part. The samples were provided with copper electrodes and saturated with water after hardening. The electrical properties of the mortars were monitored by means of impedance spectroscopy during the gradual drying of the samples. The effect of microstructure has been studied using scanning electron microscopy and mercury intrusion porosimetry. The results indicate that a significant increase in electrical resistance occurs only when the relative sorption humidity content is below 20 per cent in the 40–5000 Hz frequency range.
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The influence of alkali activator on immobilization of metals in alkali activated blast furnace slag
Bystrianska, Emília ; Kalina, Lukáš (referee) ; Koplík, Jan (advisor)
In this work the influence of alkaline activator on immobilization of lead and copper in alkali-activated blast furnace slag was investigated. A total of five activators were used; sodium water glass, potassium water glass, sodium hydroxide, potassium hydroxide and sodium carbonate. The leaching test according to ČSN EN 12457-4 was used to evaluate the level of immobilization of heavy metals, the leached solutions were analyzed by ICP-OES. For a better understanding of immobilization, the selected samples were characterized by analytical methods (FTIR, XRD, SEM, XPS). It was found that the degree of immobilization Pb2+ and Cu2+ in AAS was very high, regardless of the type of alkaline activator used.
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Effect of curing conditions on the properties of alkali activated slag
Rypák, Peter ; Bayer, Patrik (referee) ; Rovnaník, Pavel (advisor)
Combination of fine ground granulated slag with proper alkaline activator gives alkali-activated slag – a material with remarkable properties. Theoretical part of the thesis deals with summarizing basic informations about alkali-activated slag, its properties, production and utilization. It also follows research devoted to effects of curing of alkali activated slag and shrinkage-reducing admixtures on its properties. Objective of the experimental part is to determine the influence of curing conditions on the mechanical properties and microstructure of alkali-activated slag. These properties are also monitored in alkali-activated slag with carbon nanotubes and hydroxypropylmethylcellulose as an shrinkage-reducing admixtures.
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