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The generation of tailings is an inevitable concern of mining operations, since they are generated in large quantities and affect the environment both qualitatively and quantitatively. Rarely are minerals found pure in nature; generally they are found in small concentrations in raw ore, which requires processing to extract the metal of interest. Among the various methods of tailings disposal, the most common at Brazilian mines is superficial disposal of tailings in the form of slurry, using tailings dams. These facilities must be designed and constructed to manage large quantities of water as well. Regarding the mining of iron ore in Brazil, there is a trend of increased production of tailings, which has generated growing concern among companies wanting to minimise the environmental impacts and costs associated with the disposal and containment of such material. Thus, ways to manage tailings is a topic of great interest to mining companies, which have been looking for alternative disposal methods that are cost-effective and environmentally safe. Dewatering of tailings has become an attractive alternative that mitigates the environmental and social impacts of mining. Beyond that, the new resolutions under the National Dam Safety Policy in Brazil, associated with lower filtering equipment costs and other advantages, make tailing filtration an attractive alternative to the current methods of surface tailings deposition, particularly when applied in other countries in areas where the availability of space and water is limited. The objective of this paper is to show the result of a conceptual analysis of tailings disposal in the Iron Quadrangle region of the state of Minas Gerais, through a case study of the technique of filtered tailings disposal. The methodology of this work consisted of developing conceptual and hypothetical scenarios for modelling tailings disposal alternatives. These scenarios involved the use of the tailings filtration technique and the conventional technique used for tailings disposal in Brazil. The data used in this study incorporated the studies of process engineering conducted by Guimaraes (2011) for evaluating dewatered tailings from the Iron Quadrangle. In this context, this paper also contributes to understanding of the geotechnical conditions for filtered tailings disposal and to prediction of the performance of this technique. |
