Hydrodynamics of spouted and spout‐fluidized beds at high temperature

Hydrodynamic parameters were investigated in a 0.15 m diameter half‐column spout‐fluidized bed at temperatures up to 880°C for ratios of auxiliary air flow to total air flow from 0 to 0.62 and four narrow size ranges of silica sand. Equations in the literature gave poor agreement with the minimum spouting velocity over the entire temperature range. For large particles Um generally increased with temperature, while for small particles it decreased. Auxiliary air had more influence at elevated temperatures than at room temperature. Pulsations leading to choking appeared to cause spout termination at elevated temperatures. The McNab and Bridgwater (1977) equation correctly predicted the observed trends for maximum spoutable bed depth at high temperatures.