Effect of Particle Penetration Depth on Solid/liquid Mass Transfer Rate by Particle Blowing Technique

抄録

In this study, cold model experiments on particle blowing were carried out to clarify the effect of particle penetration depth on solid/liquid mass transfer rate. A comparison of penetration depth obtained by experiment and CFD calculation using commercially available software was also carried out. The penetration depth was measured by a visual observation whereas the solid/liquid mass transfer rate was obtained from the ion-exchanged reaction between Na⁺ on pearlite particles and H⁺ in HCl aqueous solution. Both of the penetration depth and solid/liquid mass transfer rate increased with the increase in particle feed rate and top blowing gas flow rate, and the decrease in lance height and particle diameter. The following non-dimensional equation of particle penetration depth was obtained by several non-dimensional numbers:

where, Re_P: particle Reynolds number, Fr: Froude number, We: Weber number, ρ_l and ρ_p: liquid and particle densities (kg/m³), respectively. A good agreement was confirmed by the experiment. The particle penetration depth was also calculated by a combination of VOF and DEM model and it was in good agreement with the experiment. The solid/liquid mass transfer coefficient calculated by the CFD simulation and Froessling equation increased with the increase in top blowing gas flow rate, particle feed rate and penetration depth. The solid/liquid interfacial area was expressed by a function of penetration depth.