Entrainment probability of coal particle by bubble trailing vortex in coal flotation

•Two typical coal particle trajectories around the cylinder tailing vortex region were measured.•Entrainment probability increased as coal particle size decreased, increased as particle density decreased, and increased as fluid flow velocity increased.•Entrainment probability increased as particle flowability increased independently of particle size, and the increase mainly concentrated in the range of particle flowability less than 12.5.