Feedstock conversion and yield products are studied through a 3D model simulating the main reactor of the fluid catalytic cracking (FCC) process. Computational fluid dynamic (CFD) is used with Eulerian-Eulerian approach to predict the fluid catalytic cracking behavior. The model considers 12 lumps with catalyst deactivation by coke and poisoning by alkaline nitrides and polycyclic aromatic adsorption to estimate the kinetic behavior which, starting from a given feedstock, produces several cracking products. Different feedstock compositions are considered. The model is compared with sampling data at industrial operation conditions. The simulation model is able to represent accurately the products behavior for the different operating conditions considered. All the conditions considered were solved using a solver ANSYS CFX 14.0. The different operation process variables and hydrodynamic effects of the industrial riser of a fluid catalytic cracking (FCC) are evaluated. Predictions from the model are shown and comparison with experimental conversion and yields products are presented; recommendations are drawn to establish the conditions to obtain higher product yields in the industrial process.

Abstract-A three dimensional gas-solid reactive flow model based on the Eulerian-Eulerian approach was used to study the effects of different nozzle designs with internal parts inside the FCC riser. The simulations were solved using Computational Fluid Dynamics (CFD) with CFX version 14.0 as tool. The results showed that the nozzle designs have a significant influence on the gas-solid behavior, resulting in an important role in the hydrodynamics and thermal behavior of the riser. Furthermore, the simulations show it is possible to improve the catalyst-gas distribution with an appropriate nozzle design.

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La simulación de una caldera industrial en CFD se realiza, usualmente, por etapas debido al gran tamaño y a los diferentes fenómenos físicos que ocurren dentro del equipo. En este trabajo, la simulación de una caldera industrial de parrilla se realiza en tres etapas, la primera es el circuito de aire primario, la segunda es el circuito de aire secundario y la tercera corresponde a la caldera. La combustión de bagazo de caña es un fenómeno complejo que involucra vaporización de la humedad, devolatilización y combustión del carbón, de forma que para evaluar esos fenómenos las partículas de bagazo fueron modeladas en un marco Euleriano-Lagrangiano. Las simulaciones fueron desarrolladas en el software comercial ANSYS FLUENT y la tasa de devolatilización fue programada en lenguaje C como una función definida por el usuario. Cuando los resultados de las simulaciones se compararon con datos experimentales, se observó una concordancia satisfactoria. Se realizaron simulaciones con modificaciones en las entradas de aire primario y secundario buscando optimizar el funcionamiento de la caldera y los resultados de esas simulaciones presentaron una mejoría significativa en los parámetros de combustión.

In a 3D model simulating in the riser of the fluid catalytic cracking (FCC) was studied feedstock conversion and yield products. Computational fluid dynamics (CFD) and Eulerian-Eulerian approach with a 12-lump model was used to predict the hydrodynamic and kinetic behavior, respectively. All the equations and conditions were solved using a solver Ansys CFX 14.0. The different operation variables and hydrodynamic effects of the riser are evaluated. Predictions from the model are shown and comparison with experimental data is presented; recommendations are drawn to establish the conditions to obtain higher product yields in the industrial process.