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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
311

Vývoj vysokohodnotných betonů s využitím druhotných surovin / The development of high performance concrete with secondary raw materials

Osuská, Lucia January 2016 (has links)
The thesis is focused on the possibility of using secondary energy resources as an additive to concrete to improve some of its resulting properties. The theoretical part is devoted to the problems of shrinkage and prominence hydration process during hydration of the concrete. This section also contains the results of research work from domestic and foreign sources of high temperature fly ash and fluidized bed combustion fly ash use and their using in concrete. The practical part verifies the possibility of using these materials and their combination as an additive to concrete with impact on the physical and mechanical properties.
312

Aktivace vysokoteplotního popílku přídavkem popílku fluidního pro výrobu betonu / Activation of high ash addition of fly ash for concrete production fluid

Ťažký, Martin January 2016 (has links)
Secondary energy products are used in the construction industry for a long time. More strict environmental limits for emissions to air have created new technologies combustion of materials in thermal power plants. In this way combustion are produced a new secondary energy products. It is an attempt to find of suitable use for these products. Their use will have ecological impact on the environment and it will allow prepare of new compositions of higher utility properties. The aim of this study was to develop a new mixture, using the new secondary energy products, for production concrete with high utility properties.
313

Synthesis and electrochemical characterisation of conducting polyaniline-fly ash matrix composites

Mavundla, Sipho Enos January 2005 (has links)
>Magister Scientiae - MSc / The aim of this study was to produce useful composite materials from fly ash, a major waste product of coal combustion from power plants. Polyaniline-fly ash (PANI-FA) composites were prepared by in situ polymerisation of aniline in the presence of Fly Ash (FA) by two slightly different methods. In one case polystyrene sulphonic acid (PSSA) was used as a stabilizer and in another case the starting materials (aniline and FA) were aged before oxidation. The aging procedure formed nanotubes that have cross-sectional diameters of 50-110 nm. The other procedure produced nanotubes with a diameter of 100-500 nm and the length of up to 10μm. The presence of metal oxides and silica in FA were responsible for the formation of nanorods in PANI-PSSA-FA.. The formation of the composites was confirmed by UV-Vis and FTIR. The UV-Vis showed maximum absorbance at 330-360 nm ( due to π-π* transition of benzoid rings) and 600-650 nm(due to charge transfer excitons of quinoid rings), which are characteristics of emaraldine base. The electrochemical analysis of the composites showed that the composites were conductive and electroactive. The Cyclic Voltammetry of PANI-PSSA-FA showed three redox couples which are characteristics of sulphonated PANI. The morphology of the composites was studied by Scanning Electron Microscopy (SEM) and showed that our methods gave composites with improved homogeneity as compared to other reported methods. Thermo Gravimetric analysis (TGA) showed that the presence of FA in the composites improves the thermal stability of the composites by up to 100 0C.
314

Infestação de moscas-das-frutas (Diptera: Tephritidae e Lonchaeidae) relacionada à fenologia da goiabeira (Psidium guajava L.), nespereira (Eriobotrya japonica Lindl.) e do pessegueiro (Prunus persica Batsch) / Correlating the infestation of fruit flies (Diptera: Tephritidae and Loncheidae) to the guava, peach and loquat trees phenology

Miguel Francisco de Souza Filho 17 March 2006 (has links)
Os experimentos de campo foram realizados em 2002 e 2003 em três pomares no município de Monte Alegre do Sul, SP, representados por uma coleção de linhagens de goiabeiras (janeiro a abril), uma coleção de cultivares de nespereiras (agosto a setembro) e uma coleção de cultivares de pessegueiros (setembro a outubro). Nos ensaios de infestação, foram utilizadas três linhagens de goiaba (Guanabara, L7P28 e 252), duas cultivares de nêspera (Precoce Campinas e a Precoce 264-54) e três cultivares de pêssego (Aurora 2, Dourado 1 e Régis). Para a determinação do período de infestação, aplicou-se o processo de ensacamento e desensacamento quinzenal e semanal da goiaba e nêspera, respectivamente, e apenas o ensacamento semanal no pêssego. Cada experimento iniciou-se com os frutos ainda no início de seu desenvolvimento (frutos verdes). Para o processo de desensacamento, no início dos experimentos foram ensacados 500 e 400 frutos de goiaba e nêspera, respectivamente. Em cada ensaio, desde o início (frutos verdes pequenos) até a completa maturação, quinzenalmente (goiaba) ou semanalmente (nêspera e pêssego) foi ensacada/desensacada uma amostra de 30 frutos, os comprimentos e diâmetro eram mensurados e retirava-se amostras para realização das análises físico-químicas em laboratório. Após o completo amadurecimento, os frutos foram colhidos e levados ao laboratório, onde foram pesados, medidos os diâmetro e comprimento e depois acondicionados individualmente em copos plásticos com areia+vermiculita até aproximadamente a metade e cobertos com “voil” preso com fita elástica. Para o conhecimento da flutuação populacional das moscas, foram instaladas três armadilhas modelo McPhail com torula (atraente alimentar) em cada pomar, de janeiro/2002 a janeiro/2004. Das moscas-das-frutas originadas dos frutos, foram identificadas cinco espécies de tefritídeos e oito espécies de lonqueídeos. Os parasitóides emergidos foram das famílias Braconidae e Figitidae, representados por cinco espécies de cada uma. Ceratitis capitata apresentou comportamento sazonal com picos populacionais durante o segundo semestre. Verificou-se que a população de moscas-das-frutas (Anastrepha spp. e lonqueídeos) se mantém na área dos pomares (goiaba, nêspera e pêssego) durante o ano todo. Os três hospedeiros sofreram o ataque de moscas-das-frutas nos seus primeiros estádios de desenvolvimento, a partir de 2 cm de diâmetro. Ao longo do desenvolvimento, em todos os hospedeiros (goiaba, nêspera e pêssego), a infestação foi ascendente, apresentando as maiores elevações no final do amadurecimento. Os parâmetros físicos (tamanho, firmeza, brix e cor) mostraram-se mais confiáveis para o prognóstico da suscetibilidade do fruto ao ataque das moscas-das-frutas do que os parâmetros químicos (pH, acidez e umidade) para todos os hospedeiros. Os aspectos ecológicos da infestação dos frutos pela moscas-das-frutas e a relação tritrófica (parasitóide/mosca/fruto) foram discutidos. / Field experiments were conducted in three orchards in Monte Alegre do Sul, SP, each containing either a collection of strains of peach (September to October), guava (January to April) or loquat (August to September), during 2002 and 2003. Three strains of guava (Guanabara, L7P28 and 252), two of loquat (Precoce Campinas and Precoce 264-54) and three of peach (Aurora 2, Dourado 1 and Régis) were used for infestation assessment. Guava and loquat fruits were bagged and unbagged biweekly and weekly, respectively, for the assessment of the infestation period and only weekly for the peach. In all cases, fruits were bagged at the beginning of their development, while still green. A sample of 30 bagged fruits were unbagged weekly (loquat and peach) or biweekly (guava) until fruits were completely ripe, from a total of 500 (guava) and 400 (loquat) fruits. Fruits were measured and a sample was taken for physicochemical analysis. Fruits were harvested once they were ripe, taken to the laboratory, weighted and measured. They were placed into plastic cups half-filled with sand and covered with a fine fabric to allow for field-collected fly development. Three McPhail traps containing Torula yeast (food attractant) were hung from January/2002 to January/2004 to assess the population fluctuation of fruit flies in each orchard. Five tephritids and eight lonchaeids species emerged from field-collected fruits maintained in the lab. Five species each of braconid and figitid fruit fly parasitoids were also observed emerging from these fruits. Ceratitis capitata showed a sazonal behavior with population density peaking at the second semester. It was also observed that Anastrepha spp. and lonchaeids remained in the orchards throughout the year. All three host fruits larger than 2 cm in diameter were infested by fruit flies at the early stages of development. Fruit infestation increased in all orchards as fruit development occurred with the highest infestation level observed at the end of the ripening. Physical parameters, such as size, firmness, brix and color were more reliable in estimating fruit susceptibility to fruit-flies than the chemical parameters evaluated (pH, acidity and humidity) for all three host fruits. The ecological aspects of the infestation of fruits by fruit flies and the tritrophic interactions (parasitoid/fruit fly/fruit) were discussed.
315

Akumulace těžkých kovů v tkáních bezobratlých živočichů na struskopopílkových odkalištích / Accumulation of heavy metals in tissues of terrestrial arthropods at fly ash deposits

Mengr, Jan January 2017 (has links)
No description available.
316

Uppskalning av fluglarvskompostering : Luftningsbehov och ventilation / Scaling-up of fly larvae composting treatment : Aeration need and ventilation

Johannesdottir, Solveig January 2017 (has links)
Genom fluglarvskompostering erhålls biomassa från organiskt avfall samt en näringsrik behandlingsrest som kan användas som gödningsmedel eller för biogasutvinning. Larvbiomassan kan användas som djurfoder eller för att tillverka biodiesel. Eskilstuna Strängnäs Energi och Miljö AB planerar bygga en pilotanläggning för fluglarvskompostering med larver av den amerikanska vapenflugan (Hermetia illucens). Behandlingen ska ske i lådor staplade på varandra, avskilda med ett mellanrum för att tillåta luftning av materialet. Luftningsbehovet utgörs av larvernas syrebehov samt av att transportera bort fukt och värme från materialet. Syftet med det här projektet var att utvärdera luftningsbehovet under fluglarvskomposteringsbehandling av matavfall med staplade behandlingslådor. Först designades ett experimentskåp att utföra experimenten i och därefter ett ventilationssystem till skåpet. Två experiment utfördes där tre staplar med nio behandlingslådor vardera utvärderades. I experiment I användes totalt 15 kg matavfall och 15 000 larver per behandlingslåda, i experiment II användes 11 kg matavfall och 10 000 larver per behandlingslåda. Under experimenten togs prover för torrsubstans (TS) och glödförlust (VS), pH samt tillväxt av larverna. Sensorer mätte lufttemperatur, relativ luftfuktighet och materialtemperatur. I båda experimenten erhölls en behandlingsrest med betydligt lägre TS-halt än önskat, vilket troligtvis berodde på att luftflödet i experimentskåpet var lägre än beräknat. I experiment I evaporerade i genomsnitt 6,2 kg vatten per behandlingslåda och i experiment II 4,8 kg, vilket för båda experimenten motsvarade cirka 50 % av det med matavfallet tillsatta vattnet. Enligt resultaten av experimenten kan torrsubstansen av matavfallet reduceras med runt 60 %. Runt 32 % av torrsubstansen i matavfallet omvandlades till larvbiomassa. Materialtemperaturen var i genomsnitt 27–30 °C under experimenten. Lufttemperaturen i experimentskåpet var 27–28 °C och 31 °C i inluften. Den relativa luftfuktigheten i experimentskåpet var 59–67 % och 36 % i inluften. Baserat på resultaten krävs ett luftflöde på 8,4 m3/h per behandlingslåda för att nå en TS på 50 % i behandlingsresten om matavfallet har en TS-halt på 15 %. Baserat på resultaten är ett nedåtriktat luftflöde att föredra framför uppåtriktat i de fall ett vertikalt luftflöde används. Skillnader i temperaturer och luftfuktighet indikerade dock att det vertikala, nedåtriktade, luftflödet inte kunde förse alla behandlingslådor i staplarna med samma luftflöde. På grund av detta kan det vara lämpligt att överväga ett horisontellt luftflöde i containern i vilken behandlingen ska ske. Vidare kan det vara fördelaktigt att reglera vattenhalten i matavfallet så att stora variationer i luftningsbehov undviks eller reglera luftflödet efter vattenhalt i ingående matavfall. Inför val av ventilationsdesign rekommenderas fortsatta studier av hur höga luftflöden påverkar behandlingen. / Larvae of the Black Soldier Fly (Hermetia illucens) can convert organic waste into biomass. The residue is nutrient-rich and can be used as fertilizer or for biogas production. The aim of this study was to assess the aeration need for designing a ventilation system in a pilot plant for larvae composting in Sweden. First, a cabinet with required ventilation arrangement for performing the experiments was designed. Two experiments were performed, where three stacks each comprised of nine boxes with spacers were used. In the first experiment, a total of 15 kg of municipal food waste and 15 000 larvae were used per box. In the second experiment, a total of 11 kg food waste and 10 000 larvae were used per box. In the first experiment 6.2 kg of water evaporated per treatment box and in the second 4.8 kg, both corresponding to about 50 % of the water present in the substrate added. An average temperature of 31 °C in the inlet air resulted in temperatures of 27-30 °C in the material during the treatment. Based on the results, 8.4 m3/h of air is needed per treatment box to reach 50 % dry matter in the residue of food waste containing 15 % dry matter. The results also indicate that to reach the desired water content in the residue, there might be a need to adjust the initial water content in the food waste and use horizontal airflow in the treatment container. Before deciding on a ventilation design, further studies are necessary to assess how high airflows affect the treatment.
317

Akumulace těžkých kovů v tkáních bezobratlých živočichů na struskopopílkových odkalištích / Accumulation of heavy metals in tissues of terrestrial arthropods at fly ash deposits

Mengr, Jan January 2017 (has links)
No description available.
318

Stanovení možností zvyšování vazného potenciálu el. popílků pro výrobu cementových kompozitů / Determining the possibilities of increasing binding potencial of fly ash for the usage in cement composites

Jančaříková, Denisa Unknown Date (has links)
The deliberate use of fly ash in the production of concrete has been used for decades, but recent trends tend to maximise its utility properties. These are different types of activations from chemical through thermal to mechanical. An alkaline agent is added to chemical activation which, by etching the glass structure of the ash grain, promotes its reactivity. Mechanical activation is mainly focused on granulometry and particle size distribution curve. In this thesis three mechanical activation methods are compared: separation the ash into fractions by grain size, mixing these fractions to achieve the ideal particle size distribution curve and grinding. Four types of ash were collected from the Tušimice power plant – ash from individual electrostatic separators (I, II and III) and SESYP ash which represents the total volume of production. Ash from individual separators differ not only in the particle size but also in the chemical composition and reactivity. Better properties generally have smaller ash particles. This is used by mechanical activation by sorting. When mixing the individual ash fractions, the aim is to achieve an optimal grading curve of either the ash itself or the fine particle set in the concrete. In this work, ash is only used to calculate the mixing ratio and the grading curve according to Funk was selected as optimal. The last compared option of activation was grinding ash. Grinding was carried out in an industrial mill for 15, 30, 45, 60 and 75 minutes. The efficiency of the modified ash was monitored for cement paste in terms of rheology and for concrete in terms of consistency, strength and durability. Based on the results we can say that mechanical activation by sorting is suitable for special purposes, but it’s necessary to realise that coarser ash fractions remain unused. When mixing the fractions to ensure matrix density, the efficiency was shown mainly on the durability characteristics. Grinding cause positive effect.
319

Stomoxys calcitrans : évaluation du rôle dans la transmission de Besnoitia besnoiti et nouveaux moyens de contrôle / Stomoxys calcitrans : assessment of the role in the transmission of Besnoitia besnoiti and new methods of control

Sharif, Shukri 21 June 2018 (has links)
La mouche charbonneuse, Stomoxys calcitrans, est une mouche hématophage commune et cosmopolite. Elle est le vecteur de nombreux agents pathogènes dont Besnoitia besnoiti, une coccidie parasite des bovins à l’origine de la formation de kystes cutanés. La compétence vectorielle de S. calcitrans pour B. besnoiti reste cependant mal connue. Dans ce travail, la persistance des formes bradyzoites et tachyzoites de B. besnoiti a été évaluée sur les pièces buccales et dans le tractus digestif des mouches. Dans ces conditions expérimentales, B. besnoiti persiste deux jours au maximum chez les stomoxes. La destruction rapide du parasite chez ce vecteur suggère que la transmission vectorielle mécanique ne peut avoir lieu que très peu de temps après un repas contaminant sur un hôte bovin infecté. De plus, nous avons étudié la capacité des stomoxes à transmettre les formes bradyzoites ou tachyzoites à des lapins, utilisés ici comme animaux modèles de besnoitiose. Des repas interrompus de stomoxes ont été réalisés sur des bovins en phase chronique de besnoitiose (source de formes bradyzoites dans leur peau) ou bien sur du sang contaminé avec des tachyzoites de culture. Le repas a ensuite été complété sur des lapins. Les résultats de cette étude ont montré que 300 stomoxes sont suffisants pour transmettre des bradyzoites virulents d’un bovin à un lapin qui a montré des signes de besnoitiose aigue et une séroconversion. Dans la troisième partie de ce travail, des méthodes alternatives aux insecticides ont été testées afin de proposer des stratégies de contrôle efficaces et pérennes contre ces vecteurs. L’attractivité pour les stomoxes de sept types d’écrans bleus, présentant entre eux de légères variations de réflectance autour de 460 nm, a été étudiée, de même que les facteurs influençant l’efficacité des pièges (hauteur par rapport au sol, orientation est ou ouest de l’écran, proximité de différents hôtes ou d’un tas de fumier). Les résultats ont montré une très grande attractivité, de très hauts niveaux de capture et une grande sélectivité de tous les écrans testés. Un total de 164692 stomoxes a été capturé au cours de l’étude (soit 24 jours de piégeage avec 4 écrans par jour et 8 heures par jour). La moitié inférieure des écrans a capturé la majorité des stomoxes (70%), de même, le nombre de stomoxes capturés par la partie de l’écran orientée à l’Est est plus important que sur la face orientée à l’Ouest. Ces éléments soulignent l’intérêt de cetype de dispositifs dans la lutte contre les stomoxes. / The Stable fly, Stomoxys calcitrans, is a common and worldwide-distributed blood-feeding fly. It is the vector of numerous pathogens including Besnoitia besnoiti, a cyst-forming coccidian parasite of cattle. Vector competency of S. calcitrans for B. besnoiti remains poorly understood. We investigated here the persistence of bradyzoites and tachyzoites forms of B. besnoiti on mouthparts and in digestive tract of S. calcitrans. In experimental conditions, B. besnoiti proved to persist until two days in stable flies. The fast destruction of parasite within this vector suggests that mechanical transmission could occur a short time only after a contaminated blood meal. Moreover, we investigated the competence of stable flies to transmit immediately B besnoiti bradyzoites and tachyzoites to susceptible rabbits after an interrupted blood meal on chronically infected cows (source of bradyzoites) or on a tachyzoite-contaminated blood meal. The results show that 300 S. calcitrans only were able to transmit virulent bradyzoites to rabbits which suffered from clinical signs of acute besnoitiosis and seroconverted. In the third part of this study, we examined sustainable methods as alternative to insecticides but efficient to control this pest. Seven different types of blue screens, with slight differences in their reflectance around 460 nm, were tested in order to evaluate their attractiveness for stable flies and to determine the factors associated with the efficiency of trapping (height of screens, east versus west side of blue screen, proximity of different hosts and manure). The results showed high attractiveness, high number of captures and very high selectivity of all tested screens, with a total number of 164692 stable flies during the study (24 days of capture, 4 blue screens per day, 8 hours per day). The results showed that the lower part of the blue screens caught the majority of stable flies, whereas the east orientation was the most attractive which caught up to 60 % of the total number captured of stable flies. Taking together, these results are highlighting the interest of these new devices in the future control of stable flies.
320

Characterization, Stabilization, and Utilization of Waste-to-Energy Residues in Civil Engineering Applications

Tian, Yixi January 2022 (has links)
About 27 million metric tons of municipal solid waste are used annually as fuel in U.S. Waste-to-Energy (WTE) power plants, which annually generate seven million tons of bottom ash (BA) and fly ash (FA). In the U.S., bottom ash and fly ash residues are mixed to “combined ash” (CA) in the approximate ratio of 6 to 1, and are disposed in landfills after metal separation. The disposal of WTE ash is a significant cost and land use item of waste management. This dissertation aims to (i) comprehensively understand the characterization and properties of WTE ash; (ii) provide practical and economic stabilization technologies to reduce the leachability of heavy metals in WTE ash and assessing whether it can be further beneficially used as secondary materials; (iii) utilize the stabilized/processed WTE ash as secondary construction materials in civil engineering applications, thus diverting materials from landfills and contributing to the circular economy. The Characterization section provides a comprehensive assessment of WTE bottom ash, fly ash, and combined ash, including chemical composition (XRF, ICP-OES, IC), mineral composition (X-ray diffraction-XRD quantification), thermogravimetric analysis (TGA), particle size distribution, and scanning electron microscopy (SEM). The physical properties of WTE residues were also investigated, including moisture, bulk density, specific gravity, void content, and water absorption. Leaching Environmental Assessment Framework (LEAF) Method 1313 of the U.S. Environmental Protection Agency (EPA) was used to understand the effect of eluate pH on the leachability of heavy metals. Combination of the above methods was applied to quantify the crystalline and amorphous phases present in WTE residues and produced specimens. In the U.S., WTE BA is discharged from the combustion chamber into a water tank. The BA includes 50-70% mineral fraction, 15-30% glass and ceramics, 5-13% ferrous metals, 2-5% non-ferrous metals, and 1-5% unburned organics. This thesis received the BA samples after ferrous and non-ferrous metal recycling. The major chemical composition includes SiO2 (34%), CaO (21%), Al2O3 (9%), and Fe2O3 (11%). According to XRD quantification results, BA consists of 76% amorphous phases (glass and metastable minerals), and the dominant crystalline mineral is quartz (SiO2, 12%). The calcium silicate (aluminate) hydrates (C-S-(A)-H) gel formed during the water quenching process embeds fine particles in the amorphous phases. The U.S. WTE air pollution control systems commonly include semi-dry scrubbers, with a few plants using dry scrubbers. FA consists of two kinds of particles: the furnace particles carried in the process gas and the newly-formed particles in the scrubber. The major chemical composition in FA includes CaO (40%), Cl (15%), SO3 (8%), CO2 (8%), and activated carbon/organic matter (3%) due to the injection of absorbents (hydrated lime and activated carbon) and the effects of flue gas scrubbing. The empirical formulae of the constituent crystalline (40-50%) and amorphous (50-60%) phases were derived. The excess water in semi-dry scrubbers improved the hydration reaction between newly-formed particles and furnace particles and resulted in the transformation of amorphous phase to calcium silicate hydrates (C-S-H) phase. The hydration products of semi-dry FA immobilized some heavy metals and reduced their leachability to below the levels of the Resource Conservation and Recovery Act (RCRA) by Toxic Characteristic Leaching Procedure (TCLP) test, as compared to dry scrubber FA, which exceeded the limits of RCRA. The U.S. combined ash can pass the TCLP test and comply with the RCRA standards for non-hazardous landfill disposal. The Stabilization section examines the effects of processing combined ash. CA undergoes water washing, crushing, and size separation processes to three fractions: coarse (27%, CCA, 9.5-25 mm), medium (37%, MCA, 2-9.5 mm), and fine (25%, FCA, < 2 mm), identified by particle size distribution results. The by-products of the washing process are extra fine filter cake ash (EFFCA, 8% of CA) collected from the water treatment system and ash dissolved in the wastewater (3% of CA). The characterization (chemical composition, mineral composition, and leachability) of ash the fractions (CCA, MCA, and FCA) showed that their mineral changed during the processing and exhibited significantly lower leachability (LEAF Method 1313-pH dependence), in comparison to as-received CA. The processed ash fractions with reduced leachability of heavy metals, can be further beneficially used as secondary materials. The effect of pH of the washing agents (water, acid and alkaline solutions) on the chemical/mineral transformation and the heavy metals leachability of the FA, BA, and CA was assessed. A novel technique of determining the distribution of various elements in washed ash (product), filter cake (by-product), and wastewater (dissolution) during ash processing was developed to compare the effectiveness of the washing process, which is dominated by dissolution and precipitation reactions. As-received FA, BA, and CA contained 50-75% of amorphous phases in metastable status, which are transformed to crystalline phases during the washing process. It was concluded that water washing is the most practical method for transforming WTE CA to construction material. The Utilization section examined the use of WTE ash in civil engineering applications, i.e. (i) Using the CCA and MCA fractions as stone aggregate substitute in structural concrete; (ii) Using FCA as sand substitute or using the milled FCA (MFCA) powder as mineral addition in cement mortar; (iii) Using FCA and EFFCA powder as metakaolin substitute in artificial aggregate; (iv) Using FA and phosphate FA (PFA) as cement substitute in cement mortar. In conclusion, the CA size fractions, i.e., MCA and CCA, are suitable for use as aggregate substitutes in the production of structural concrete. Up to 100 wt.% of stone aggregate in concrete can be substituted by MCA and CCA. The compressive strength of the optimal products exceeds 28 MPa after 28 days of curing, which is comparable to commercial concrete products using natural stone aggregate. The optimum concrete mixture composition was 40 wt.% of MCA or CCA, 30 wt.% sand, 20 wt.% cement, 10 wt.% water, and superplasticizer, with compressive strength of 28-30 MPa and elastic modulus of 6,300-6,600 MPa. The optimal products complied with stringent leaching standards, and the properties of the final products were comparable to the conventional civil engineering materials. All FCA or MFCA products were effectively stabilized/solidified and transformed to non-hazardous material that can be used in construction. The main challenge in the utilization of FCA or MFCA in cement mortar is the cementitious phase expansion due to the metallic aluminum present in FCA or MFCA. It was concluded that up to 50 vol.% of sand in cement mortar can be directly substituted by FCA, and up to 25 vol.% of MFCA can be utilized as mineral addition to replace cement in the production of cement mortar. In the production of artificial aggregates, up to 15% of FCA or up to 10% of EFFCA can replace metakaolin by volume. The produced samples indicated crushing strength of 4 and 1.5 MPa, respectively. The specific gravity and water absorption of optimal ash aggregate is 1.3 and 30%. The FCA and EFFCA aggregates exhibited good chemical stability and reduced the cracks observed in the fire resistance test. The ash aggregates can be used as a lightweight aggregate for non-structural applications. FCA can improve the workability of the metakaolin mixture and extend the setting time, which is beneficial for geopolymer aggregate manufacturing. The heavy metals from FCA and EFFCA can be effectively stabilized/solidified in artificial aggregate. Phosphoric acid can effectively stabilize the as-received FA, so that the dry scrubber FA passes the TCLP test and complies with the RCRA standards. The mineral transformations of individual ash and ash-cement paste were investigated by the XRD quantification analysis. FA and PFA enhanced the hydration degree of cement, and received higher mechanical performance than reference in 0-25 vol.% cement replacement. The leachability of heavy metals was effectively reduced in a wide leaching range (eluate pH 0-12.5), realized the stabilization/solidification purposes under restricted non-hazardous landfill standards.

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