THEORY OF SOLIDS PROJECTION FROM A FLUIDIZED BED SURFACE AS A FIRST STEP IN THE ANALYSIS OF ENTRAINMENT PROCESSES.

A theory is developed for a quantitative treatment of solids projection from a dense fluidized-bed surface. First, it is presupposed that the solids projected into the freeboard are originally contained in the bulges formed when gas bubbles approach the dense bed surface. With the relative movement between dense bed surface and bubbles described by the potential flow theory, an expression for the solids projection rate is delineated. Measurements of the elutriation rate are extrapolated to the dense bed surface for comparison with the theory. Good agreement is observed except in the region of very high gas velocities where slugging prevailed.