Factorial CFD study of a chemical looping combustion reactor aimed at increasing fuel conversion and CO 2 capture

Abstract A factorial parametric approach based on CFD simulations was employed in this study to systematically analyze a chemical looping combustion system using two-dimensional numerical modeling. This methodology made it possible to identify the operating conditions that enhance the conversion of fuel gases and the inherent separation of CO 2 , enabling its capture and preventing its release into the atmosphere. Initially, eight simulations were evaluated by varying the inlet gas velocity and the initial temperature of the granular phase. Based on the results of the factorial parametric study, an additional simulation (Case 9) was performed by combining the most favorable operating conditions and boundary conditions identified in the factorial analysis. The simulations were conducted using the Eulerian multiphase model to represent the granular and gaseous phases, incorporating heterogeneous reactions between particles and gases, the species transport model, and the k–ε turbulence model. The results show increases in the molar concentrations of CO 2 at the outlet of the fuel reactor: for Case 1, the CO 2 concentration increased by a factor of 2.6; for Case 3, by a factor of 10; and for Case 9, by approximately 85, relative to a reference study. Additionally, a higher inlet gas velocity was observed to adversely affect particle distribution within the reactors.