Desenvolvimento de cerâmica vermelha com incorporação de cinzas de carvão de olarias e filito

Abstract

This study investigated the effects of incorporation of phyllite and coal ash as a raw material for the production of a red ceramic. The waste used was fly ash produced at the ceramic industries of the region. The clay and the phyllite used as ceramic matrix was extracted from the neighboring of Marabá – PA - Brazil. The raw materials were characterized by their chemical and mineralogical composition. Samples were prepared with amounts of 5, 15 and 25% fly ash, 35, 40 and 45% phyllite and 40, 45 and 50% clay, to obtain specimens. The specimens were sintered at the temperatures of 1050 ºC, 1100 ºC and 1150 ° C with heating rate of 10 ° C / min with 2 hours of soaking time. After the step of firing, the ceramic samples were characterized according to their technological performance, which evaluated their physical (linear shrinkage, water absorption, bulk density and porosity) and mechanical properties (three point bending strength). From the technological point of view the samples of all formulations behaved like typical traditional ceramic materials, and as the sintering temperature was increased, to a certain extent, a reduction in water absorption, apparent porosity and an increase of bulk density were observed, as well as an increase in linear shrinkage and bending strength were achieved. According to the results obtained in this work, the addition of fly ash, in association to phyllite and clay to produce ceramics was feasible from a technological standpoint.