With the decreasing availability of high-quality mineral resources and the increasing complexity of ore properties, efficient and sustainable flotation technology has become a research focus in the field of mineral processing. To optimize the taper angle of the air distributor in a KYF flotation machine, numerical simulation was used in this study to investigate its influence on the internal flow field, gas-phase characteristics, structural pressure distribution, and stirring power consumption. The results show that the peak turbulent kinetic energy and gas holdup are concentrated in the shear zone between the impeller and stator. Under the +5° condition, the peak turbulent kinetic energy is the lowest, while its vertical distribution is the most uniform. The peak gas holdup in the impeller–stator region reaches 19.2%, and the number of efficient bubbles with a diameter of 0.5 mm reaches 3.8 × 106 per m3, which is significantly higher than under the other conditions. During stable operation, this condition exhibits the lowest stirring power consumption at 126.0 W, which is 7.557% and 4.255% lower than under the −5° and 0° conditions, respectively. The optimal taper angle is therefore determined to be +5°. However, the associated large pressure gradient on the impeller surface may accelerate blade wear, indicating that surface strengthening measures should be considered to balance performance and durability.
Lv et al. (Wed,) studied this question.