No abstract

In existing tailings-discharge (TD) systems, the feeding, settlement and discharge are conducted alternately in multiple vertical silos. A model of continuous TD, which differs from the aforementioned model, is proposed to solve the problems of the high fluctuation in underflow concentration and the relatively low, unstable actual discharge concentration in vertical tailings silos. The continuous discharge of the tailings in the silo was simulated using computational fluid dynamics software. In the simulation, four slurry-underflow conditions were selected to record the corresponding compression-region height and the variation of the slurry concentration with that height based on preset monitoring curves. In addition, a relationship between the tailings volume fraction and silo height was obtained by fitting, and a predictive model was proposed for the change in the volume fraction of the underflow tailings with the compression-region height. A new working mode of the discharge system in the backfilling system was proposed, and fluent software was used to simulate the new discharge system. Industrial field tests verified the reliability of the results of the numerical simulations. It greatly improved the work efficiency of the vertical silos as it reduced the number of working vertical silos, omitted the process of completely discharging and charging the silos, and simplified the preparation of the slurry materials. With these advantages, the model guaranteed the filling efficiency and quality. Applying the proposed model of continuous TD for vertical silos effectively overcame the technical problems facing the existing TD systems in mines.