The dynamic images of gas-liquid-solid three-phase flow in the riser were obtained by the high-speed camera system,the variation of the lifting performance of three-phase flow with operating parameters were studied,and the flow field structure and the movement characteristics of solid particles in the riser were analyzed based on the image processing method.The result showed that the periodic variation of flow pattern is formed in the riser,in turn,spare bubble flow-intensive bubble flow-bubble churn flow-mixed churn flow-spare bubble flow,in which the bubble churn flow is more conductive to lift solid particles.Under the same amount of air inlet,the discharged amount of solid,liquid and lifting-efficiency increases first and then decreases with the increase of submergence ratio.The effect of air inlet on the performance of system is higher than that of submergence under the same operating conditions.During the low flow rate of air,the particle concentration is low and most of it concentrate in the pipe wall.With the increase of air flow rate,the particles move to the core,and the particle concentration and the lifting velocity are more higher than other parts.In addition,the gas-liquid two-phase flow and gas-liquid-solid three-phase flow is appeared in turns in the riser with the change of air let,and the particle distribution and motion state also be affected by it.The system was proved a better performance,compared with the single particle,under the action of group particles.Particularly the velocity of particles in different radial positions are not equally distributed about the center line of the pipe.
