Impellers play a key role in flotation cells, as the turbulence generated through agitation aids particle suspension, air dispersion and particle–bubble collision. Therefore, it is important to understand the effect that different impeller designs have on flotation hydrodynamics, as small variations could enhance flotation performance. The study of flotation hydrodynamics is, however, a complex task due to the nature of flotation systems, which are opaque, multiphase, and polydisperse. In this paper, the impact of impeller design modifications on the hydrodynamics of a flotation cell was quantified for the first time in a three-phase system. Two different impeller designs, with and without a stator, were assessed using positron emission particle tracking (PEPT), a technique that allows the position and velocity of radioactive particle tracers within an opaque vessel to be determined. A novel PEPT data analysis strategy, as well as a statistical analysis on the basis of the Jensen–Shannon distance, were used. This statistical analysis, applied for the first time to PEPT data, facilitated the comparison of the different designs, by generating a robust quantification of their hydrodynamic differences. The experimental results showed that the stator significantly modified the hydrodynamics within the flotation cell, distorting the lower mixing loop that is characteristic of radial impellers. The use of a stator also resulted in the reduction of particle velocity and swirling outside of the impeller–stator region, both at the level of the impeller and, notably, at the pulp–froth interface. These findings have important implications for impeller–stator design, evidencing that the impeller has a direct effect on the hydrodynamics of the pulp and froth.

叶轮在浮选槽中起着关键作用，因为通过搅拌产生的湍流有助于颗粒悬浮、空气分散和颗粒-气泡碰撞。因此，了解不同叶轮设计对浮选流体动力学的影响非常重要，因为小的变化可以提高浮选性能。然而，由于不透明、多相和多分散的浮选系统的性质，浮选流体动力学的研究是一项复杂的任务。在本文中，叶轮设计修改对浮选槽流体动力学的影响首次在三相系统中进行了量化。使用正电子发射粒子跟踪 (PEPT) 评估了带和不带定子的两种不同叶轮设计，一种允许确定不透明容器内放射性粒子示踪剂的位置和速度的技术。使用了一种新的 PEPT 数据分析策略，以及基于 Jensen-Shannon 距离的统计分析。这种统计分析首次应用于 PEPT 数据，通过对其流体动力学差异进行稳健的量化，促进了不同设计的比较。实验结果表明，定子显着改变了浮选槽内的流体动力学，扭曲了径向叶轮特有的下部混合回路。定子的使用还导致叶轮 - 定子区域外的粒子速度和漩涡的降低，在叶轮的水平，特别是在纸浆 - 泡沫界面。