Gas-solid-liquid reactive CFD simulation of an industrial RFCC riser with investigation of feed injection

Abstract

The feed injection zone involving gas–solid-liquid mixing, vaporization and reaction plays an important role in fluid catalytic cracking reactors. Our previous cold-model simulation indicated that a modification from the conventionally upward feed injection scheme to a downward one improves the oil-catalyst matching. This work aims to investigate the effects of such downward feed injection on the reaction behaviors through three-phase reactive simulation of an industrial riser. A twelve-lump kinetics and vaporization of liquid oil were considered in a multiphase Eulerian model with the energy-minimization multi-scale model. The predicted solids flux, temperature, and solids concentration were compared with experimental data. The simulation showed that the downward injection with an angle of around 30° and suitable mounting position helps improving the yield of gasoline and LPG and mitigating adhesion of the coking layer to the wall. We expect such an approach sheds light on the optimization of the three-phase chemical reactors.