Abstract The aim of this paper is to analyze mixtures of basic oxygen furnace slag and granite waste in order to produce Portland cement. X-ray patterns were carried out in both the basic oxygen furnace slag and granite waste. Then, mixtures were prepared to obtain the binary basicity of 0.5, 0.9 and 1.2. The mixtures were melted at 1500ºC. Two cooling steps were performed. The first cooling step was accomplished inside the furnace in order to determine the phases formed during the melting step. The second cooling process was carried out in water in order to obtain an amorphous structure. Images via scanning electrons microscopy and EDS spectrum were obtained for the mixtures cooling in water. The results showed that basic oxygen furnace slag contains a higher percent of CaO. A binary basicity of 4.6 was determined. The granite waste appeared as mainly a quartz phase. During the slow cooling step, silicates (akermanite and gehlenite) were formed. On the fast cooling step, amorphous structures were obtained. In addition, images obtained via scanning electrons microscopy showed glass structures. EDS spectrum indicated that the glass structures were composed for calcium silicates. Thus, the results suggest that mixtures using basic oxygen furnace slag and granite waste presented characteristics desirable for Portland cement production.

Esse trabalho estuda a viabilidade técnica da fabricação de cimento com uma mistura de resíduo proveniente da serragem de blocos de granito e escória de aciaria LD. Para isso, foi preparada uma mistura desses materiais de modo que a relação %CaO / %SiO2 fosse 1,2. Essa mistura foi fundida e resfriada rapidamente em água. A amostra foi caracterizada e o difratograma de raios X mostrou um material amorfo e a presença das fases mineralógicas Akermanita e Gehlenita, as quais são consideradas como as fases mineralógicas ideais para a atividade hidráulica. Essa mistura foi adicionada ao clínquer para a fabricação de cimento. Com o cimento fabricado, foram feitos ensaios cujos resultados são apresentados e comparados com os valores obtidos para o cimento de alto-forno. Esses resultados indicam a viabilidade técnica da utilização da mistura na fabricação de cimento.

This article studies the technical feasibility of manufacturing cement agglomerated with granite block sawing waste and LD steel slag. The materials were mixed in order to maintain the relationship %CaO / %SiO2 of the mixture equal to 1:2. The mixture was melted and rapidly cooled in water. The sample was characterized and the X-ray diffractograms showed an amorphous material and the presence of mineral phases akermanite and gehlenite, which were considered ideal mineral phases for hydraulic activity. This mixture was added to clinker for cement production. The cement made with this mixture was tested for comparison with the blast furnace slag cement. These results indicate a technical feasibility for manufacturing cement with this mixture.

Esse trabalho estuda a viabilidade técnica do aproveitamento de resíduo proveniente do corte de granito para ajustar a basicidade (relação CaO/SiO2) da escória de aciaria LD, visando a sua utilização na fabricação de cimento Portland. Para isso, foram realizadas a caracterização química dos resíduos e a sua mistura e fusão, a fim de se obter uma relação CaO/SiO2 em torno de 0,9 e 1,2. As misturas fundidas foram resfriadas em água e ao forno. Nas amostras resfriadas em água, após uma análise por difratometria de raios X, constatou-se que estas se apresentaram, predominantemente, amorfas. Para as amostras resfriadas ao forno, que se apresentaram cristalinas, observou-se a presença das fases mineralógicas Akermanita e Gehlenita, as quais são consideradas como as fases mineralógicas ideais para a atividade hidráulica das escórias. Esses resultados permitem concluir que o ajuste da basicidade da escória de aciaria LD através da adição de resíduo de granito mostrou-se eficiente, indicando a sua viabilidade técnica para a fabricação de cimento Portland.

This study focuses on the technical feasibility of the utilization of waste from the cutting of granite to adjust the chemical composition of slag from steelworks LD, targeting the addition of clinker Portland cement. For this, chemical characterization of the waste, its mixture and fusion was performed, obtaining a CaO/SiO2 relationship of around 0.9 to 1.2 for the steelworks slag. We selected samples of the waste, mixed, melted and cooled in water and in the oven. Samples cooled in water, after examining with X-ray difractrograms, had been predominantly amorphous. For samples cooled in the furnace, which had vitreous, there was the presence of mineralogical phases Akermanita and Gehlenita, which is considered as the ideal stage for the mineral water activity of the slag. The adjustment of the chemical composition of the slag from steel works by the addition of waste granite was efficient, transforming the waste into a product that is the same as blast furnace slag and can be used in the manufacture of cement.

Esse trabalho tem os objetivos de caracterizar o resíduo de manta cerâmica, gerado no lingotamento contínuo dos aços, devido à diminuição da sua capacidade de isolamento térmico, e de estudar a viabilidade técnica da utilização desse resíduo na fabricação de argamassa. O resíduo foi submetido à análise química, difração de raios X e MEV e utilizado na preparação de argamassa. Foram feitas dosagens de 0%, 2%, e 6% em massa do resíduo, em substituição ao cimento, e realizado o ensaio de índice de consistência e compressão na argamassa. Dessa maneira, obtiveram-se resultados em três argamassas distintas. Os resultados indicam um aumento na resistência à compressão com adição do resíduo, em comparação com a argamassa-padrão, e o índice de consistência apresentou alterações pouco consideráveis.

The goal of this study is to characterize the waste of ceramic blankets used in the thermal insulation of the continuous casting machine, which was generated due to the decrease in the capacity of thermal insulation. It also investigated the technical feasibility of the use of this waste as raw material to produce mortar. The waste was characterized by chemical analysis, X-ray diffraction, and SEM. Proportions of 0%, 2%, and 6% of the mass of the waste were used in substitution of cement in the production of mortar samples. Samples were tested to obtain the consistency index and mortar compression tests. The results indicate an increase in the compression resistance with the addition of waste in comparison with standard mortar. The consistency index was not affected by the additions.