Abstract: The open turbine rotating disc contactor (OTRDC) has been constructed by adding three narrow strips to the lower surface of each rotating disc in the rotating disc contactor (RDC), so that it can be used for liquid-liquid-solid system with high solid particle content. Experiments were carried out in a 0.152 m diameter contactor using quartz particles, tap water (continuous phase) and kerosene (dispersed phase). The variables studied were the rotor speed, compartment height, stator ring opening, and the superficial velocities. Correlations for predicting holdup and backflow ratio of solid phase have been given.Experimental results have shown that (1) OTRDC is feasible for liquid-liquid-solid system; (2) the solid phase axial mixing is mainly determined by the particle size distribution and rotor speed.