• A gas–solid coupling theoretical model for dust generation and migration in high ore passes was established: systematically analyzing the combined effects of induced airflow, shear airflow, and impact airflow. The governing equations for airflow motion, dust particle dynamics, and diffusion were derived, providing a solid theoretical basis for subsequent numerical simulations. • EDEM–Fluent coupled simulations revealed the spatiotemporal distribution characteristics of dust: dust concentration rises rapidly to its peak during the initial unloading stage, followed by fluctuating decay; smaller particle sizes exhibit longer suspension times and wider dispersion ranges; dust in the connecting drifts is predominantly within the 1–100 μm range, with a high proportion of respirable particles. • The influence patterns of multiple factors on dust pollution levels were clarified: increasing the ore discharge rate, raising the intermediate section height, and reducing ore particle size all significantly elevate peak concentrations and prolong the duration of high dust levels; simultaneous unloading from multiple sections produces superimposed impact airflows and multi-peak concentration processes, intensifying dust dispersion and accumulation. . In contemporary mining operations, dust pollution generated during ore discharge from high ore passes presents a critical challenge. This study examines the distribution and migration patterns of dust during ore discharge in multi-level high ore passes. Through theoretical analysis, the research elucidates the mechanisms of dust generation under the combined effects of induced airflow, shear flow, and impact airflow. Theoretical models encompassing gas flow dynamics, dust particle force analysis and motion, and diffusion equations are established to support numerical simulations. Using the Lilu Iron Mine as a case study, a geometric model was developed with precise boundary conditions. To the best of our knowledge, few studies have employed coupled EDEM–Fluent simulations to comprehensively capture the gas–solid interactions governing dust generation and migration, which constitutes the research gap this work seeks to fill. Coupled EDEM–Fluent simulations were utilized to analyze the spatiotemporal distribution characteristics of dust concentration under various parameters, including discharge flow rate, intermediate level height, ore particle size, and simultaneous multi-level discharge. The findings demonstrate that increased discharge rates, greater intermediate level heights, and reduced ore particle sizes result in elevated dust concentration peaks with extended durations. During multi-level simultaneous discharge, interacting impact airflows and multi-point ore movement generate rapid increases in dust concentration. Additionally, staggered discharge timing and fluctuations in instantaneous flow rates produce multiple dust concentration peaks. This investigation provides essential theoretical foundation and practical guidance for optimizing ore discharge procedures and reducing dust pollution, thereby enhancing working conditions in underground mining environments.
Wang et al. (Sun,) studied this question.