Avaliação técnica e ambiental da incorporação de pó de aciaria elétrica (PAE) em material cerâmico

Abstract

Scientific and technological researches have been indicated the possibility of recycling several kinds of waste in construction, among which it stands out the electric arc furnace dust (EAFD). The EAFD is originated in the steelmaking process and classified as a hazardous waste (ABNT, 2004a). The aim of this research was to evaluate the technical and environmental viability of ceramic material produced from EAFD addition in red clay. The methodological stage included sampling of raw materials, its chemical, physical, mineralogical and thermal characterization. Also, the formulation and molding of compositions with 0, 10, 20 and 30% of EAFD and the sampling of atmospheric emissions from sintering at 750, 850 e 950°C. Finally, it was realized technical and environmental tests in the obtained material. Among the results, it was verified that the red clay has in its chemical composition, Al, Si and K as majoritarian elements, while EAFD has, mainly, Fe and Zn. Besides that, the red clay has larger particle than EAFD’s, which in turn has spherical particles which tends to form agglomerates. As result of the thermal treatment, it was observed that the addition of 10 and 20% of EAFD and sintering at 850 and 950°C produces a material indicated to bricks in function of its flexural strength and water absorption. In environment terms, it can be concluded that additions up to 20% of EAFD processing at 750°C produce a material classified as not inert, according NBR 10006 (ABNT, 2004d) due to its Al content. Regarding atmospheric emissions, excluded the addition of 30% of EAFD sintering at 850°C, all conditions are according to the reference norms, even though there is no specific standard to this activity. In a global perspective, it is indicated the use of EAFD up to 10% to bricks sintering above 850°C, predicting its accordance to red ceramic specifications.