In this paper, a correlation between axial mixing in a discs and doughnuts pulsed extraction column, the geometrical characteristics of the column, and the pulsation conditions is established by numerical experimentation. The calculation method, based on the computational fluid dynamics approach and detailed on an example, consists in evaluating the axial dispersion coefficient from simulations of tracer mixing, transported by the turbulent pulsed flow in the column. Hydrodynamic characteristics of flow and tracer transport are calculated by the ESTET code. The results concerning the mean velocity fields of the oscillatory turbulent flow show a transition from an unstable to a stable recirculation regime. The stability of the recirculations and their size depend only on one geometrical parameter which is the distance between successive discs and doughnuts. A quantitative analysis of the dispersion process is obtained from the time variation’s study of the tracer cloud’s spatial moments. The results reveal that the distance between successive discs and doughnuts is the key parameter governing axial mixing in such columns. This work also confirms the proportionality observed by other authors between the axial dispersion coefficient and the pulsation intensity. Numerical results are compared with the experimental ones available.