Impact assessment of waste screening over the life of a Brazilian bauxite mining operation

ABSTRACT The mining sector is looking for new technologies to minimise its environmental impacts and to maximise its reserves. The need to increase the life of mines has led to investigations considering the options to maximise Brazilian bauxite mine reserves. This work evaluates the use of a flip screen in the loader bucket to recover ore from the overburden. The study investigates both the financial and technical feasibilities of this option. This device results in a decrease in the amount of waste and an increase in the life of mine. An average mass recovery of 48% is achieved. The concentration of the bauxite present in the overburden is possible using only screening and the oversized (>12.7 mm) product contains 40% of the available alumina, with less than 4% reactive silica and 0.5% organic carbon, which is acceptable for the Bayer process.