Iron ore tailings dry stacking in Pau Branco mine, Brazil.

Abstract

tThe mining industry has seen several significant dam failures in recent years. Dam failuresare associated with errors in design, implementation, operation, and monitoring (Azam,2014, [2]). Dewatered stockpiling (dry stacking) is a safer alternative to tailings dams (Ricoet al., 2008, [3]) for tailings disposal; however, this method has not yet been used in ironore mines in Brazil, where geotechnical conditions and abundance of water are favorablefor the use of tailings dams. This paper describes the results of the study that supportedthe implementation of an innovative dewatering plant for iron ore tailings in Pau Brancomine, Quadrilatero Ferrifero, Brazil, contributing to improve its sustainability (Gomes et al.,2015, [6]). Magnetic concentration rejects (>45 m) were feasibly dewatered through high-frequency screenings, and slimes (<45 m) were effectively filtered in a horizontal filterpress, enabling dry stacking of tailings. A comparison with the current tailings dam struc-ture is presented, demonstrating that Capital Expenditure (CAPEX) for the solution proposedhere is significantly lower.