Modeling and Simulation of an Industrial Fluid Catalytic Cracking Riser Reactor Using a Lump-Kinetic Model for a Distinct Feedstock

A process model for an industrial fluid catalytic cracking reactor is an important tool for predicting the flexibility to operate with different feedstocks within the expected range of conversion, yield of gasoline, and coke production. In this work, a steady-state process model has been developed to describe a two-phase transported-bed riser reactor that incorporates the stripping section and uses a lump-kinetic scheme to account for the cracking of different feedstocks characterized by the paraffin, aromatic, and naphthene contents. The dependency of the kinetic parameters on the type of feedstock is accounted for by expressing frequency factors as a function of the aromatic/naphthenic ratio in the feedstock. The stripping section, where the recovery of adsorbed hydrocarbons takes place, is modeled as a continuous stirred tank reactor where mainly the thermal cracking of the adsorbed species takes place. The process model is used to predict product yields from the catalytic cracking of three different gas oils, and the comparison with industrial data shows a good prediction.