Sensitive dependency of minimum spouting velocity on angle of repose of solid particles and cone angle in conical spouted beds

Minimum spouting velocity (u(ms)) varies with the geometry of a Spouted Bed (SB) contactor and the gas-solid properties. The angle of repose (theta(r)), being an important bulk property of the solid granules, is found to play a critical role causing the variation of u(ms) with a change in contactor angle (y(c)). A systematic experimental study was conducted considering three different types of solid particles having significantly different theta(r) (25(degrees), 36(degrees) & 45(degrees)) and three different yc (28(degrees), 45(degrees) & 60(degrees)) for three different gas inlet diameters, to evaluate U-ms and bed pressure drop (Delta Pb). The variation of Ums is correlated with (tan yc/2) and it is found to have three distinct zones for different 0r for which exponent over (tan yc/2), epsilon, is highly affected making a significant change in ums.