Investigation of a jet and stirring synergistic flotation column combining two-phase flow and particle tracking simulation methods with experiments

Abstract

This paper details the design concept of a jet and stirring synergistic flotation column; it conducts a simulation study of the internal flow field using the two-phase flow module and particle tracking module in COMSOL software; and it establishes a 15-l jet and stirring synergistic flotation column for experimental research. The results show that in the jet-stirring coupling structure of the device, the flow field exhibits high turbulent kinetic energy and turbulence dissipation rate, which facilitates collision and mixing in the three-phase system. The device modifies coal slurry particles, increasing the slurry contact angle and enhancing the hydrophobicity of the particles. The speed distribution of the flow field, gas distribution, and particle distribution within the column are reasonable. The uniformity coefficient of aeration within the column reaches 96.10 %, and the solid-liquid ratio at sampling points on different height planes is similar, with no dead zones or particle accumulation. The flotation column with jet and stirring synergy exhibits good flotation performance, with the recovery rate reaching its maximum after 1 min, the flotation yield reaching 53.96 % within 5 min, and the ash content of the flotation clean coal stabilizing at 11.29 %, qualifying as high-quality flotation clean coal. The device shows good adaptability and demonstrates good flotation performance under conditions of low air intake. This study provides a new technical solution for efficiently separating fine-grained minerals, holds potential for further industrial development, and has positive significance for the R&D of flotation equipment and three-phase mixing devices.