Bauxite residue (BR), a by-product of alumina and aluminum production, consists of high aluminum, silica, and iron content, and sodium from the bauxite ore digestion during the Bayer process. This waste is still being disposal into the lakes of mud, causing some environmental problems. So, the search for its application has gained interest. Studies reported in literature point out that one of the most promising applications is in association with Portland cement, which can also help to reduce the environmental impact caused by the CO2-emissions in its production. In this work, a combined evaluation of oscillatory rheometry and isothermal calorimetry was performed for the monitoring of the hardening stage of Portland cement (PC) compositions blended with BR generated in different sites in Brazil. The time-sweep test was applied to obtain the consistency gain of suspensions over-time, allowing us to understand the physical parameters of consolidation, while the changes in the hydration reaction showed considerable differences in the chemical contribution. As a conclusion, it was clear the impact of each BR, mainly due to the aspects related to soluble aluminates, silicates, and sodium, which in association with the soluble ions from PC, affected the chemical reaction and agglomeration/flocculation forces of particles.
Agradeço primeiramente à Deus, que me guiou por esse caminho, me dando forças quando nem eu mesmo tive, fazendo eu acreditar no meu potencial.Ao meu pai Vandair e minha mãe Guiomar, que na base da minha criação humilde moldaram meu caráter e que me ensinaram acima de tudo que o caminho correto é sempre o mais digno, embora, muitas vezes o mais doloroso.A minha noiva Pamela, que nunca duvidou do meu potencial, sempre acreditou na minha capacidade e me levou para cima nos momentos difíceis. Ela que segurou a barra num dos momentos mais difíceis da minha vida sendo uma das pessoas mais importantes nesse trajeto até a conclusão dessa dissertação. Sem palavras para enaltecer essa mulher, é um privilégio ter sua companhia ao meu lado.Ao meu orientador, Sérgio Angulo, pela paciência, compreensão e orientação de maneira a proporcionar diálogos abertos. Sua orientação foi exemplar em todos os aspectos.Obrigado pelas oportunidades oferecidas ao longo desse trajeto e pela amizade construída.
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