Brazilian coals contain high levels of impurities (pyrite and sedimentary rocks minerals), requiring concentration procedures. The coal tailing deposits demand a large physical area, whose topography is changed and acid mine drainage (AMD) is generated. The aim of this work was to characterize a typical coal tailing deposit in the carboniferous region of Santa Catarina, seeking the separation of three fractions for future reuse: (a) a fraction for energy production; (b) a fraction composed mainly by silicate minerals; and (c) a fraction with a high concentration of pyrite. The work methodology consisted in sample collection and characterization of the material. The characterization included particle size analysis, dissymmetric studies, XRD analysis, petrography studies, and acid-base accounting tests. The results showed that 68% of the material is composed of coarse particles, 15% of fine particles, and 17% of slurry from settling ponds. It is possible, by gravimetric concentration of the material, to recover 33.7% for energetic application and 10.3% as a pyrite concentrate. The remaining material, with intermediate density, will have a decrease of about 60% in its net acid generation potential and presents potential for application in civil engineering construction.
Coal tailings; coal preparation; environment