The thesis deals with possibilities of FBC fly ash utilization for composite cements. It focuses on thermodynamic stability of ettringite, which is produced during composite cements hydration. Specific tasks are dedicated to observation of influence of outdoor environment and influence of calciumhydrosilicate environment to stability of ettringite.

The subject of this thesis is the conversion and alternative proposal to the existing steel structure roofing the winter stadium in Jindrichuv Hradec. The building has a rectangular plan with dimensions of 80 x 52 m. The roof structure consists of lattice trusses and purlins, plotted using lattice steel columns. The other possibilities are parabolic lattice trusses and purlin with fly bracing that were designed and evaluated in accordance with applicable standards. The solution using parabolic trusses is designed on the original footprint of the structure. The distance of each bond is 8 m.

Alkali activated materials have great potential to be a material that could compete with Portland cement. Compared to concretes based on Portland cement they often exhibit greater durability and resistance to aggressive agents such as sulphates. Also their resistance to high temperature is substantial. This work is devoted to research on behavior of alkali-activated materials, particularly fly ash activated by sodium water glass and sodium hydroxide, exposed to these extreme conditions. The evaluation of properties was performed based on the detection of physico-mechanical parameters and microstructure examination by RTG diffraction analysis and scanning electron microscopy (SEM).

Betong är vårt vanligaste byggmaterial men cement står globalt sett för 5 % av CO2-emissionerna. Med detta som bakgrund så har CBI Betonginstitutet anordnat en tävling, där målet är att nå den högsta tryckhållfasthet i en resurssnål betong, med enbart 200 kg cement per m3. Syftet med denna rapport är att utvärdera tävlingen, vilket har utförts genom en omfattande litteraturstudie.  En första analys av de olika betongrecepten medförde att olika grupperingar kunde urskiljas. Ur dessa fanns det tre stycken vars resultat var väldigt bra.   Concrete Innovation Centre, som med ett lågt vct, stora mängder granulerad masugnsslagg (81 %) och lite silikastoft (5 %), uppnådde en tryckhållfasthet på 80 MPa vid 28 dygn och 95 MPa vid 56 dygn.   CBI Stockholm, som genom användandet av ulltrafint filler och silikastoft (4,8 %), uppnådde en tryckhållfasthet på 84 MPa vid 28 dygn och 98 MPa vid 56 dygn.   Thomas Concrete Group som genom att ersätta cementet med en medelmåttig mängd granulerad masugnsslagg (54 %), liten mängd flygaska (9 %), kalkfiller och silikastoft (5 %), uppnådde en tryckhållfasthet på 94 MPa vid 28 dygn och 98 MPa vid 56 dygn.  Det finns således tre recept som vidare studier kan vara rättfärdigade på, de tre ovan nämnda. Det bör tilläggas att en imponerande tryckhållfasthet på nästan 100 MPa, kan uppnås i en betong med enbart 200 kg cement per m3. / Concrete is the most frequently used construction material, but cement globally stands for 5 % of the world’s CO2 emissions. With this as a background CBI Betonginstitutet has arranged a competition, where the goal is to reach the highest compressive strength in a resource economic concrete, with only 200 kg cement per m3. The purpose of this report is to evaluate the competition, which has been done via a substantial literature study.  A first analysis of the different concrete recipes resulted in that different groups could be identified. From these there were three recipes whose result was very good.   Concrete Innovation Centre, which with a low w/c, a high amount of ground granulated blast furnace slag (81 %) and little silica fume (5 %), reached a compressive strength of 80 MPa at 28 days and 95 MPa at 56 days.   CBI Stockholm, which by the usage of ultrafine filler and silica fume (4,8 %), reached a compressive strength of 84 MPa at 28 days and 98 MPa at 56 days.   Thomas Concrete Group, which by replacing the cement with a moderate amount of ground granulated blast furnace slag (54 %), a small amount of fly ash (9 %), lime filler and silica fume (5 %), reached a compressive strength of 94 MPa at 28 days and 98 MPa at 56 days.  The conclusion is that there are three recipes that further studies are justified to continue with, the three mentioned above. It should be added that an impressive concrete compressive strength of almost 100 MPa, can be reach with the use of only 200 kg cement per m3.

Black soldier fly larvae (BSFL) waste treatment is becoming a more sought-after organic waste treatment since it produces larvae for animal feed as well as fertilizer, the need for prediction and optimization of treatment performance increases. This study aims to predict biomass conversion efficiency (BCE) for waste going into treatment, using only the nutritional data from other studies as it could give a good performance estimation while using available data. First, macronutrient fractions, based on a normalized total weight of volatile solids (VS), were calculated from nutritional data of other studies and of this present study.  Using the results, coordinates of these samples were calculated and put on the ternary plot, revealing trends for different macronutrient compositions. To validate these trends, selected nutrient compositions were created as waste mixtures containing fish, bread and vegetable waste and then treated by BSFL. After treatment, BCE and waste reduction in both VS and wet weight basis were noted.  The results showed that a composition high in carbohydrate and low in fat content is favorable for a high BCE value while protein content remained similar across all treatments and only seemed to slightly increase BCE. Treatment A5 held the highest BCE%VS (32.6 ± 3.5) with a composition of 73%VS carbohydrates, 19%VS protein and 8%VS fat and control treatment (A0) with no fish waste held the highest BCE%WW  (21.2 ± 1.8).   When comparing with the results of the other studies used to make the trends in the ternary plot, predictions of BCE were more accurate for a composition  of  70%VS carbohydrates, 20-25%VS protein and < 8%VS fat and also for compositions with similar waste substrates, as their percental changes were similar. This suggests that it is possible to predict high BCE  values from nutritional data in a ternary plot and could be of use when optimizing larval production. / Fluglarvskompostering med den amerikanska vapensflugan (Hermetia illucens) är en avfallsbehandling för organiskt avfall som producerar larver och gödselmedel som kan används som djurfoder respektive gödselmedel.  Många studier har undersökt hur makronäringsämnen påverkar larvproduktion eller behandlingseffektiviteten och kommit till olika resultat. I dagens läge skulle det underlätta om man kunde uppskatta den högsta möjliga effektiviteten baserat på data om avfallet som redan finns utan att behöva gå igenom en längre studie först. Den här studien har som syfte att undersöka om det är möjligt att förutspå biomassomvandlings-effektivitet (BCE) från makronäringsdata tagen från andra studier i ett triangulärt diagram. I denna studie användes studierna av Lopes et al., (2020) och Isibika et al., (2021) som basdata i triangulär diagrammet.  För att validera det trender som sågs i det triangulära diagrammet utfördes tester på valda kompositioner beståendes av ansjovis, bröd och grönsaksavfall med fluglarvkompostering. För att kunna applicera makronäringsämnernas data till triangulär diagrammet, beräknades mängden protein, kolhydrater och fett som en andel av den totala mängden glödförlust (VS).  Efter behandling beräknades BCE på våtvikt (WW) och VS basis.  Resultaten tyder på att en avfallskomposition med hög halt kolhydrater och låg halt fett (70%VS kolhydrater, 20–25%VS protein and <8%VS fett) bidrog till ett högt BCE värde, där proteinhalten var snarlik i alla behandlingar och verkade ha ett litet bidrag till ett högt BCE värde. Behandlingen A5 hade det högsta BCE%VS värdet (32.6 ± 3.5) med en komposition av 73%VS kolhydrater, 19%VS protein och 8%VS fett och kontroll behandlingen A0 (utan ansjovis avfall) hade högst BCE%WW värde (21.2 ± 1.8).   Vid jämförelse mellan de andra studierna och resultaten, var uppskattningar av BCE mer precisa för en komposition med ca 70%VS kolhydrater, 20–25%VS protein and <8%VS fett och för uppskattningar baserad på data från rapporter med liknande avfallssubstrat, då deras procentuella förändringar var liknande varandra. Detta stärker hypotesen att det är möjligt att kunna förutspå högt BCE värde med hjälp av näringsdata från avfallet och skulle kunna användas för att optimera av larvproduktion.

Reducing the impact of modern industrial production on the environment and reducing the waste generated is undoubtedly one of the most discussed topics of the present time. In the production of fossil-fueled electricity, a large amount of fine-grained waste fly ash is generated. The possible use of ash as secondary raw materials in the construction and building materials industry is one of the many environmental challenges that the energy industry is concerned with. The aim of this diploma thesis was to verify possibilities of utilization of different kinds of power station fly ash as filler in asphalt mixtures for the production of oxidized asphalt insulation strips. The main emphasis was put on the clarification of the influence of the properties of the different types of fly ashes on the resulting rheological behavior of the mixture of asphalt binder and power fly ash, which is professionally called mastic. Mastic forms a technology-critical insulating layer in the asphalt insulation strip. The prediction of the rheological properties and therefore the workability of mastic appears to be an essential element in the management of production, especially under the conditions of the variability of input raw materials. In order to solve the assigned task it was necessary to perform detailed analyzes of fly ash properties, to select the corresponding quantification variable for assessment of the mastic processability and to find the signal fly ash properties, which appears to be a control parameter of workability. As a suitable method for assessing the processability of mastic, a shear viscosity measurement method was chosen. On the basis of the findings, it is possible to state that the use of fly ash from the production of oxidized asphalt bands is not recommended as the mastic prepared from these fly ashes are unprocessed at the assumed concentrations. The negative effect of fly ash after denitrification on the mastic processability has not been demonstrated.

Electroconductive composites are modern materials that are commonly used in many industries such as the construction industry among others. For example these materials can be useful as sensors for monitoring changes in constructions. The aim of this thesis is the research of electrically conductive silicate composite based on secondary raw materials. The design of this composite is based on the development of its own mixtures and experimental verification of the effect of the structure. The introduction part consists of a detailed analysis of 15 materials. Samples of the 5 fine and 2 coarse electrically conductive fillers were tested. Composite with filler Condufit C4 was selected as representative for type of fine fillers. Composite with filler Supragraphite C300 was selected as representative for type of coarse fillers. The selection of the composites was based on the impedance of the fabricated composites with these fillers. Subsequently, the individual components of the primary mixture were substituted. The cement was replaced by high-temperature fly ash in the amount of 20, 30, and 40 %, the aggregate of a similar fraction was replaced by steel sawdust, and the primary electrically conductive fillers were replaced by secondary ones in the amount of 30 and 50 %. All proposed replacements reduced the impedance of the composite. The most effective replacement for impedance reduction was replacement with waste graphite (up to 92 % reduction), which also slightly improved the mechanical properties of the composite. The result of this thesis is an optimized electrically conductive composite based on secondary raw materials with a fine type of filler with 30 % replacement by waste graphite "odpad vysavač"which achieves an impedance of 5 ohms. The partial goal of this thesis is a verification of the influence of moisture on the impedance of composites. Results are significantly affected by moisture when using the coarse type of filler, when using the fine type are not.

In line with the current focus on utilizing side products of various production processes, this dissertation thesis analyzes the process of alkali activation of particular side products: fly ash and brick fragments. This activation produces geopolymeric materials widely used in civil engineering. The thesis aims to optimize the geopolymerization process so that the resulting geopolymer is both ecologically and economically viable. To that end, the thesis studies the course of geopolymeric reaction between the alkali activator and fly ash from: (i) the Chvaletice power plant, (ii) the Dětmarovice power plant, and (iii) biomass combustion, as well as (iv) fluid fly ash from the Hodonín power plant. All experiments of geopolymeric reaction have focused on the factors influencing the synthesis of geopolymers—that is: composition of the alkali activator, the ratio of alumino-silicate to the activator, and the impact of temperature on structure of the synthesized geopolymer. Further, the thesis analyzed the synthesized polymer’s microstructure, phase composition, resistance against corrosive conditions, and compressive strength, as well as mechanical-fracture properties of selected fly-ash geopolymers. The thesis finds that the most suitable for geopolymeric synthesis appears to be the fly ash from the Chvaletice power plant in which case the obtained geopolymers showed best properties in the studied areas. The fly ash from the Dětmarovice power plant, biomass fly ash, and fluid fly ash have failed to reach acceptable properties. Separately, the thesis studies the geopolymerization of brick body that could be suitable input for alkali activation. The geopolymers synthesized from brick fragments resulted in materials of supperior mechanical strength. A mixed use of fly ash and brick fragments failed to show a synergetic effect. Properties of the resulting geopolymers have been inferior to the properties of geopolymers produced using just fly ash or just brick body.

Wood-polymer composite is a relatively new type of material that combines shattered wood mass and a thermoplastic polymer. This material is utilized especially as an alternative to hard wood in the area of non-bearing exterior elements, as it reaches better properties in terms of the basic durability and low maintenance. Raw material composition and processing of the composite enable to provide a significant modification with further matters leading to an improvement of the end-product properties. Research and development in this field focuses predominantly on the utilization of such modifying additives that either enhance the resistance to weathering or are of the recycled nature, as a significant part of the raw material mixture comprises the constituent obtained from non-renewable resources. The aim of the thesis is the evaluation of the influence of the wood-polymer composite modification separately at two levels. First of them is the modification to matrix by using a recycled polymer, the second one comprises the modification of the wood flour with a secondary spherical filler. Both types of modified composites have been assessed in terms pf the prime characteristics and the resistance to adverse ambient.

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