Numerical Simulation of Deposition Characteristics During Pipeline Transport of Sulfide Tailings Slurry

This study investigates particle distribution and deposition during pipeline transport of sulfide tailings slurry using an Eulerian multiphase model in ANSYS Fluent 2024. A 200 mm-diameter pipeline was simulated over inlet mass concentrations of 20–50%, inlet velocities of 0.5–3.0 m s−1, and pipe inclinations of 0–40°. The measured particle-size distribution was represented by seven solid size classes, and the Wasp model was used to estimate the critical deposition velocity. Results show that low velocity and high concentration promote bottom deposition and increase relative deposited-bed height, whereas increasing velocity enhances particle suspension and reduces bed thickness. Increasing pipe inclination generally intensifies deposition over much of the developed-flow region, while the longitudinal bed profile becomes non-monotonic at larger inclinations. Medium-to-coarse particles preferentially settled near the pipe bottom, whereas the 30 μm fraction exhibited a more uniform cross-sectional distribution under the representative condition examined. Industrial pressure-gradient measurements were used to evaluate the hydraulic response of the model, yielding relative errors of 1.05–4.28% and a mean absolute percentage error of 2.86%. The results provide guidance for selecting operating conditions that limit deposition during sulfide-tailings pipeline transport.