Technical and Economic Evaluation of Tailings Dewatering Circuits in the Largest Copper Mines

Several large copper mines are evaluating improvements in the tailings dewatering circuits. Most prevalent alternatives being considered optimize their thickening technologies or the implementation of tailings filtration and stacking. This requirement to optimize water recovery is due to a variety of factors; the deficit and high cost of the water make-up, environmental restrictions, and community relationships. The recent failures in conventional tailing deposit structures and the potential change to reduce the footprint of tailings impounds may also drive the desire to consider alternate technologies. This paper presents technical and economic review of alternate technologies, considering capital investment and operational costs. The five (5) selected alternatives include thickening technologies, pressure filters and a combination with cyclones for classification and filtration of the coarser fraction and thickening of the finer fraction. The selected alternatives are developed and evaluated at trade off study level.