Experimental study of particle flow in a gas-solid separator with baffles using PDPA

Particle flow behavior in a gas-solid separator with a guide baffle and separation baffles developed by the Institute of Process Engineering (IPE) for cocurrent down-flow reactors has been studied with a Phase Doppler Particle Analyzer (PDPA), which allows to measure the particle size and velocity simultaneously. Profiles of particle velocities, particle size and particle number density at different heights in the separator were obtained. Analysis of the velocity profile indicates that the particle inertia has a significant effect on the behavior of particles in different size groups: the trajectories of the smaller particles are more influenced by the gas stream in relation to the larger, more heavier, particles. Experimental results reveal that the guide baffle together with the separation baffles plays a role of guidance as well as particle concentrators. Particles entrained by the gas flowing upward along the top side of the separation baffle may mainly come from the regions far from the guide baffle surface. Small particles are gradually dispersed toward the periphery of the two-phase flow field after being ejected from the rectangular nozzle, giving rise to a bimodal behavior of particle size distributions in the region far from the guide baffle.