Abstract: As a follow-up of previous work done, the two-phase flow characteristics in a pulsed-sieve-plate extraction column are being further studied. The hindering effect of drops, the - coalescence effect of drops, the interrelation between characteristic velocity and terminal velocity of single drop in the column and the flooding velocities are discussed. Semi-empirical equations are suggested. Work done in this respect serves as a basis for the scaling up of pulsed-sieve-plate extraction columns.