Utilização do rejeito do granito Rain Forest como matéria prima alternativa para a fabricação de revestimentos cerâmicos de baixa absorção de água.

Abstract

This work describes a study on the technical viability of using Rain Forest granite rejects as an alternative raw material for the fabrication of ceramic tiles with low water absorption. The aim is to employ these tiles in the construction industry, thereby reducing the environmental impact of granite residues and minimizing fabrication costs. Initially the rejects were milled and sieved. A small amount of water was added, and the mixture was subjected to compression molding. Test samples dried for 24h and then sintered for 1h in a muffle furnace at the temperatures of 1155, 1165, 1175, 1185 and 1195 ºC, which compare to those used in industry ( from 1180 to 1250 ºC). The starting powders were characterized by X-ray fluorescence. Total weight loss during firing was determined by TGA (1.72%). DTA characteristic peaks were observed for the transition from alpha quartz to beta quartz. Linear contraction on firing was 8.5% and the water absorption measured was <0.5%. The results obtained have demonstrated the potentiality of the use granite powders for the desired application.