Developing a Modeling-Based Approach to Design a Riser Reactor in the Fluid Catalytic Cracking (FCC) Process

The fluid catalytic cracking (FCC) process is a cost-effective and reliable route to convert heavy oil fractions into valuable and light products. The riser reactors are commonly commercialized to perform this process. In this study, using a novel modeling-based approach, the design of the FCC riser reactor system is presented based on the gas oil feed with 24.1 kg s-1 mass flow rate. Subsequently, the performance of the designed reactor is examined under various operating conditions. For this purpose, an algorithm is proposed as the design procedure. Initially, the numerical model of the riser reactor is developed and then validated using experimental data including product distribution and outlet temperature. The presented numerical model matches the experimental data of an industrial unit with an average error of 7.52%. Based on the proposed design, the gas oil conversion is 94.32% and the mass fractions of products including diesel, gasoline, LPG, dry gas, and coke are 21.66%, 49.82%, 12.55%, 4.35%, and 5.94%, respectively. The process controllability to operating conditions is also determined based on the sensitivity analysis so that the catalyst-to-oil ratio (COR), feed flow rate, feed temperature, and catalyst temperature can be adjusted to achieve a desirable product distribution.