PARTICLE VELOCITY AND PARTICLE CLUSTERING IN DOWNFLOW REACTORS: MEASUREMENTS USING A CREC-GS-OPTIPROBE

摘要

Particle velocity and particle clustering are phenomena of importance in many applications in gas-solid fluidized beds. The objective of the present study was to obtain this fluid dynamic information in a downflow unit using the novel CREC-GS-Optiprobe equipped with a GRIN lens. From experimental results it is concluded that in downflow units catalyst particles (FCC particles of 76 μm) evolve as particle strings with a relatively large size distribution: average cluster size ranging between 2.0 to 6.3 times of the average particle diameter with most of the particles strings having between 2.9 and 5.5 times of the average particle diameter.