Supplement Number 1-9

See the supplementary material for Fig. S1 which states the average pressure drops curves with fluidization water velocities under different fluidization gas velocities for various particle sizes and H/D ratios. The file also consists of Figs. S2-5 showing the conductivity tomograms of air-water system in FBFC freeboard region at different superficial water velocities, superficial gas velocities, particle sizes and H/D ratios, respectively, (a-c) Time-averaged cross sectional conductivity distribution, (d-f) Time-evolution of conductivity distribution along column diameter at X=0. Fig. S6 explains the effect of H/D ratios on gas holdup measured at Uw=35.0 L/min, Ug=8.0 L/min, Dp=5.0 mm, (a) Time-averaged cross-sectional gas holdup tomograms (b) Time-averaged radial gas holdup profiles along column diameter at Y=0. And Figs. S7-9 represent the probability density histogram of BSD and its lognormal fitting curve under different superficial gas velocities, particle sizes and H/D ratios, respectively.