AN IMPROVED BUBBLE ASSEMBLAGE MODEL FOR FLUIDIZED-BED CATALYTIC REACTORS

A mathematical model based on bubble assemblage concepts for fluidized-bed catalytic reactors is presented. The bed is divided into three phases, namely, bubble, cloud-wake, and emulsion phases. The concept of axial gas mixing in the emulsion phase is incorporated. Hence, both upflow and downflow gas streams in the emulsion phase are simultaneously considered in the model. The model developed contains no adjustable parameters. Newly developed correlation equations for the predictions of bubble diameter and superficial bubble-phase gas velocity are also selected and tested for the model. Model predictions are shown to compare quite well with the various published experimental data on both axial concentration profiles and overall conversions.