Hydrodynamics of semifluidization in gas—solid systems

Hydrodynamics of regular particles in a liquid–solid semi-fluidized bed

“…The independency of U osf on static bed height for the liquid-solid system has been reported by Roy and Sarma [19] and Roy and Sharat Chandra [20]. But Ho et al [2] have reported that the static bed height slightly affects the minimum semi-fluidization velocity in a gas-solid semi-fluidized bed. They have reported a decrease in the minimum semi-fluidization velocity with the increase in initial static bed height.…”

“…The pressure drop method seems to be the best one. Ho et al [2], Fan and Wen [18], Roy and Sarma [19], and Roy and Sharat Chandra [20] have recommended the pressure drop method for the prediction of U osf .…”

“…A few of them have represented the dimensionless minimum semi-fluidization velocity as the function of system and operating variables directly viz. Ho et al [2], but some other researchers (Roy and Sarma [19], Roy and Sharat Chandra [20]) have used the system and operating variables in dimensionless form. In the present work empirical equations for U osf /U mf have been represented in both the forms for the convenient use of the designers.…”

“…The development and advantages of the semi-fluidized bed relating to studies on hydrodynamics, mass transfer, reaction kinetics and filtration have been highlighted by Murthy and Roy [1] and Ho et al [2]. Subsequently a good number of research articles relating to various applications of the semi-fluidized bed system have been reported in literature [3][4][5][6][7][8][9][10][11][12][13][14].…”

“…A semi-fluidized bed has the advantages of both the packed and the fluidized beds. The disadvantages of fluidized beds, namely back-mixing of solids, attrition of particles and erosion of surfaces, and those of packed beds, such as non-uniform bed temperatures, segregation of solids and channeling, are taken care of, at least partially in a semi-fluidized bed [1,2].…”