THE FLUIDIZED-BED CATALYTIC REACTOR - A LEARNING-MODEL FOR FAST REACTION

The two-phase model of the bubbling fluidized bed catalytic reactor is modified in anticipation of rapid reaction occurring not in series but simultaneously with mass transport between lean and dense phases. Thus is invoked an intraphase effectiveness factor governed by chemical and physical kinetics. There emerges a fluid bed efficiency (relative to fixed bed plug flow behavior) which can, in principle, be ascertained by a novel gradientless laboratory reactor strategy suggested here. The telling influences of bubble size and feed velocity relative to that of minimum fluidization are explicated in terms of conversion and yield for a linear triangular catalytic reaction network. This “learning” model teaches that (a) bubbles and their growth are detrimental to space time conversion and yield of intermediates and as a consequence (b) a well horizontally baffled fluid bed operated at high velocities such that continuous “snakes” as opposed to “bubbles” are created grants superior fluid bed performance. © 1990, American Chemical Society. All rights reserved.