Characteristics of Gas-Solid Mixture Flows through a Packed Moving Bed of Coarse Particles

The gas-solid flow through a moving bed packed with coarse particles is investigated experimentally and theoretically in this study. By employing a bench-scale moving-bed column, different sizes of fine and coarse particles, gas flowrates, and moving-bed velocities are examined to ascertain the transport characteristics of fines. We propose models to predict the transport characteristics by performing a dimensional analysis and a regularized regression by machine learning. We observe that the transport phenomena of fines are dominated by the hydrodynamic properties of fines rather than the moving-bed velocity, and the size of coarse particles also has an impact on the transport characteristics, especially the fines holdup. Additionally, the split ratio and exiting velocity of fines are found to be a function of the gas flowrate and the size of coarse particles. Results of this study can guide the design of packed moving-bed reactors that utilize fine particles as the feedstock.