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The objective of this work is to characterization of sugarcane bagasse ash waste aiming the use it in red ceramic industry. The characterization was done in terms of chemical composition, X-ray diffraction, particle size distribution, morphology, and plasticity. The results show that the cane bagasse ash waste is a non plastic material, which contains high content of silica and minor amounts of Al, Fe, Ca, Mg, and K oxides. Thus, the sugar cane bagasse ash waste presents high potential for application in the manufacture of ceramic products such as bricks, roofing tiles, and ceramic tiles.

RESUMOO Brasil é o maior produtor mundial de açúcar e álcool proveniente de cana-de-açúcar. A indústria da canade-açúcar tem contribuído para o fortalecimento do agronegócio, desenvolvimento econômico e social do país. No entanto, o processo produtivo da indústria de cana-de-açúcar gera enormes quantidades de resíduos sólidos na forma de cinzas. Estes resíduos sólidos são de difícil disposição final e podem gerar problemas de poluição ambiental. Por esse motivo, devem-se buscar novas alternativas tecnológicas viáveis para o reuso ou reciclagem destes abundantes resíduos. Este trabalho tem como objetivo utilizar o resíduo de cinzas de bagaço de cana-de-açúcar como uma matéria-prima alternativa de baixo custo em mistura com argila caulinítica para obtenção de cerâmica vermelha. Foram estudadas cinco formulações com 0, 5, 10, 15 e 20 % em peso de resíduo de bagaço de cana-de-açúcar misturado com argila caulinítica. As peças cerâmicas foram preparadas por prensagem uniaxial e sinterizadas a 1000 ºC (24 h frio a frio). As peças sinterizadas foram caracterizadas em termos de retração linear, absorção de água, massa específica aparente, porosidade aparente e resistência à compressão. Ficou comprovado, após resultados dos ensaios realizados, que a incorporação de resíduos de cinzas de bagaço de cana-de-açúcar afeta significativamente as propriedades tecnológicas de cerâmica vermelha. Portanto, o resíduo de cinzas de bagaço de cana-de-açúcar pode ser usado como uma matéria-prima alternativa de baixo custo em cerâmica vermelha, desde que seja adicionado em quantidades moderadas.Palavras-chave: Cinzas, Bagaço de Cana-de-Açúcar, Cerâmica Vermelha, Reciclagem. ABSTRACTBrazil is the world's largest producer of sugar and ethanol from sugarcane. The sugarcane industry has contributed to the strengthening of agribusiness, as well as economic and social development of the country. However, the production process of the sugarcane industry generates huge amounts of solid wastes in the form of ashes. These solid wastes have difficult disposal and can lead to problems of environmental pollution. Therefore, one should look for new alternative technologies viable for reuse or recycling of these abundant wastes. The essay's goal is to evaluate the use of sugarcane bagasse ash waste as a low cost alternative raw material mixed with clay for production of red ceramic. Five formulations were studied with 0, 5, 10, 15 and 20 wt.% of waste mixed with kaolinitic clay. Ceramic pieces were prepared by uniaxial pressing and sintered at 1000 °C (24 cold cold). The pieces were characterized in terms of linear shrinkage, water absorption, apparent density, apparent porosity and compressive strength. It was proven, after results of tests performed, the incorporation of sugarcane bagasse ash waste significantly affects the technological properties of red ceramic. Therefore, the sugarcane bagasse ash waste can be used as an alternative raw material in red ceramic, since it is added in moderate amounts.

Abstract:The aim of this work is to evaluate the effectiveness of fiberglass and ceramic fiber cylinders as root-pass weld backing for a double-V groove in 16 mm-thick carbon steel. Three different cylinder diameters were tested: 4.8, 9.5 mm (fiberglass) and 6.4 mm (ceramic fiber). The welding process used was GMAW. The welding technique and the following process variables were investigated: root opening, current and travel speed. The results show that cylindrical fiberglass and ceramic fiber backings not only have excellent refractory properties, but also seal the root opening and contain the weld pool sufficiently to produce a root bead free of discontinuities and with a satisfactory shape and geometry. Working points were defined, together with a possible operating range for the welding parameters. It was concluded that cylindrical fiberglass and ceramic fiber weld backings hold great promise for use in root-pass welds in double-V grooves in applications in the naval and metallurgical industry.