Axial mixing of continuous phase in a rotating disk extraction column has been studies by considering the flow characteristics of fluids in the column. Equations were developed to predict the effects of rotation speed of the disks

continuous-phase flow rate and disperse-phase flow rate on the axial mixing of the continuous-phase. For single phase flow

the overall axial mixing can be considered as the combined contribution from eddy diffusion and channeling phenomenon. The axial mixing of continuous-phase in single phase flow can be described by the following equation: For two phase counterflow in the column

the axial mixing of continuous-phase becomes even more complex owing to swarming of drops of disperse-phase. Physical model developed as well as experimental results indicates that axial mixing of continuous-phase could either be enhanced or diminished by the disperse-phase flow as operating conditions vary. The motion of wakes of continuous-phase behind the drops increases thebackmixing of continuous-phase. The backmixing ratio fw

from the wake movement can be represented by The movement of a swarm of drops in a continuous-phase reduces the channeling flow of continuous-phase and thus forward mixing. Decrease of the ratio of forward mixing AW can be correlated by The total contribution of disperse-phase to the axial mixing of continuous-phase is given by (fw-△W). Experimental results of axial mixing of continuous-phase in two phase counter-current flow can be represented satisfactorily by the following equation: