Unsteady three-dimensional theoretical model and numerical simulation of a 120-kW chemical looping combustion pilot plant. (16th January 2019) - Hamidouche, Ziad
Graphical abstract: Highlights: An Euler-Euler model for the two-phase flow (solid OC and gas fuel) is developed. 3D unsteady numerical simulations of a CLC unit based on a DCFB are performed. Good agreement between numerical results and experimental measurements is found. Numerical results prove the ability of the approach to predict the CLC process. The local and instantaneous CLC behavior is analyzed and discussed. Abstract: In this paper, reactive unsteady three-dimensional numerical simulations of a chemical looping combustion (CLC) unit are presented. The configuration is a 120-kW pilot plant working with perovskite, CaMn0.9 Mg0.1 O3− δ, as the selected oxygen carrier. Numerical simulations were performed using NEPTUNE_CFD code in the frame of an Euler-Euler approach by computing both gas and solid phases in an Eulerian technique, accounting for specific closures in order to model the interphase mass, and momentum and energy transfers. Heterogeneous reduction and oxidation (gas–solid) reactions were modeled by means of a grain model to account for the competing mechanisms of the chemical reaction onto the grain surface, the gaseous diffusion through the product layer around the grain, and the external transfer through the gas mixture surrounding the particle. Results from numerical simulations were assessed against experimental measurements and analyzed in order to acquire insight on the local behavior of reactive gas-particle flow in the CLC system. The theoretical/numerical tool developed in this work can be used for the design upgrade of crucial parts of the system in the stage of scaling-up from pilot to industrial plants.