where \({v_{l},\ H}_{B},\ N_{P}\), and \(\varepsilon_{i}\) indicate the
liquid velocity, column height, number of theoretical separation plates,
and interparticle voidage, respectively.
It is worth noting that the axial dispersion (mixing) usually happens
when a fluid flows through a packed column such as ion-exchangers (Gu,
2015).
In order to see where to include axial dispersion in the bed model, the
dimensionless Peclet number is employed which quantifies the degree of
the dispersion introduced into the system.