Estudo técnico-econômico conceitual para o reaproveitamento de rejeito de mineração na indústria automotiva de elementos de fricção

Abstract

The mining activity is responsible for the production of a large quantity of tailings and waste material. Over the last few decades environmental laws and requirements have been tightened regarding the disposal and recovery of materials and areas for future use. This case study is located in the district of Minas do Camaquã, in the municipality of Caçapava do Sul, state of Rio Grande do Sul, where an old dam of copper mining with about 122 ha has no future use. The tailings were deposited in the dam during 13 years, until the end of the copper mining carried out by Companhia Brasileira de Cobre (CBC). Previous technical work was done with the objective of characterizing the material deposited there, suggesting possible uses. The objective of this work is to conceptually analyze the technical and economic feasibility of using the tailings material as raw material in the manufacture of friction elements in the automotive industry. As methodology, sampling, drying and classifications techniques, fluorescence and x-ray diffraction assays were used from the tailings samples. The tests were performed in partnership with a manufacturer of friction elements, based in the city of Caxias do Sul / RS. Positive results were obtained in these trials, suggesting a sustainable reuse of mining waste, which today has no economic value, and thus reducing some of the environmental liabilities existing in this case study. A conceptual economic study was also performed, suggesting a possible operationalization of the tailings production process, obtaining a conceptual production cost that can be considered coherent when compared with commercially similar materials. The obtained results allow to conclude that the material has the qualities to be used in the composite of the friction elements, in an economically viable way, but future tests are still necessary in order to define the most appropriate proportions.