Características mineralógicas e granulométricas das fontes de poeiras no Polo Cerâmico de Santa Gertrudes - SP

Recent studies on the presence of dust flows into the atmosphere show that they can be up to eight times higher than the previously consolidated estimates. With origin mainly attributed to the new demands of uses of soils, fuels and rocks, this concentration can globally modify the main components of the Climate geosystem, and endanger the ecosystem limits which support life on the planet. Despite the importance of Brazil as a producer of mineral and agricultural commodities, and therefore a major producer of mineral dust, few such studies have been conducted. This study is related with this issue in a region known as Ceramic Cluster of Santa Gertrudes that have the largest ceramics industries of Brazil and also large agricultural production. X-ray diffraction and laser diffraction techniques were used to characterize the mineralogical composition and particle size distribution of soil (pedological source), clay mineral (lithological source) and their transformation products (terrigenous and industrial source), considered as the main emission sources of dust in this region. The presence of an assembly of silicate minerals rich in aluminum and iron that prevails in these sources of dust explains the high SiO2, Al2O3 and Fe2O3 contents found in the ore, soil and the atmosphere of the region. The predominance of minerals such as kaolinite clays can be considered as pedological source diagnostic, while the predominant illitic clays characterize the lithology source. The granulometric studies revealed that, among the various sources, the pedological is the one with the highest fraction of clay materials in MP10, and therefore has the higher potential to contribute with the resuspension processes that are efficient to transfer mineral dusts of surface to the atmosphere.