A series of well-designed deflectors were used to regulate the liquid flow behaviour on the 95-Ⅱ tray. A multiple-plug flow pattern was observed in each liquid flow channel between two deflectors on the tray.On a test rig with a diameter of 1000 mm, the liquid layer temperature profiles in the vertical and horizontal directions were measured by resistivity thermal detectors(RTDs).An oxygen desorption experiment was carried out and the oxygen concentration in the inlet liquid and the outlet liquid were determined by iodimetry,through which the liquid phrase Murphree tray efficiency(E ML) was calculated. The results show that the well-designed and placed deflectors on the tray can obviously increase the tray efficiency by almost 30% under the same operating conditions.