In Chile, over a million tons of tailings are discharged daily, of which mostare of the conventional type. Also in Chile are some of the largest depositsin terms of the extent of the flooded area, the production rate and theheight of the dam. The tailings, which constitute the residue of theflotation process, are dewatered using thickeners, the dimensions of whichdepend on the treatment rate and sedimentation of solids.The tailings deposit receives these flows, which are deposited in theimpoundment, initiating the sedimentation process that develops alongthe beaches and under water (tailings pond). The difference insedimentation between a thickener and tailings beaches is a variable flowpath as tailings are deposited on beaches.The slurry flow that enters the impoundment loses mass on its way tothe pond by solids sedimentation, retention and water evaporation. MineraEscondida is one of the largest mining operations for sulfide ore tailingstreatment in the world, and it discharges its tailings at Laguna Seca Dam(TLS) following a deposition plan.This article analyzes the tailings deposition from a point of view thatthe tailings deposit is a sedimentation area where the flow is varied, with alateral velocity component that differentiates it from a thickener, which hasonly the vertical velocity component. Through the development of massbalances, the formation of a hydraulic approach and the adoption ofhypotheses based on the observation of operations and simple laboratorytests, there is a deposition model that allows the estimate of, among others,the following variables: extent of the active tailings beach, profile thatadopted by the tailings to support spatially varied flow, variation ofparameters along the tailings beach, solid mass that reaches the pond,water retained on the beach, water retained in underwater tailings, criteriafor estimating the minimum volume of pond and application of waterbalance models.
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