Formation of Reaction Bubbles in FCC Riser Reactor

Abstract

For modeling FCC unit, art of defining undefined hydrocarbon misxtures in conjunction with application of two different specialized fields of Chemical Engineering–Chemical Reaction Engineering (CRE) and Computational Fluid Dynamics (CFD) are required. CRE needs elaboarte and appropriate definition of undefined mixture and their chemical kinetics, whereas CFD needs solution of more regorous differential equations to define fluctuating and turbulent flow. Most of the reported works in available literature seems to be strong in only one field. To bridge this gap, in the present work a commercially availble CFD simulation package with k–epsilon turbulence model is used to solve a more regorous and realistic definition of cracking kinetics. The results obtained revealed that in the emulsion phase of fluidized bed, a new “reaction bubble” phase exist. Bubbles of non uniform reaction zones are formed inside emulsion phase where mass distribution of catalyst is fairly uniform.