Computational fluid dynamics – population balance (CFD-PB) simulations are performed to predict Sauter mean drop diameter and dispersed phase holdup for liquid–liquid two-phase flow in a pulsed disc and doughnut column (PDDC). The continuity and momentum equations of the two-phases along with standard k–ε mixture model of turbulence and an appropriate model for interphase momentum exchange are solved to obtain temporal and spatial variations of dispersed phase holdup. Sauter mean drop diameter is obtained from Quadrature Method of Moments (QMOM)-based population balance model (PBM) which is solved along with the flow equations and takes into account coalescence and breakage of droplets. CFD-PB model is validated with the experimental data of Sauter mean drop diameter and dispersed phase holdup obtained for different pulsing velocities. Validated model is used to have detailed insights into the two-phase hydrodynamics prevalent inside the PDDC and to test the efficacy of scale-up methodology reported in literature.