Transient Reacting Flow Simulation of Spouted Fluidized Bed for Coal Direct Chemical Looping Combustion

Abstract

Coaldirect chemicallooping combustion (CDCLC) is a next generation combustion technology that shows great promise as a solution for the need of highefficiency lowcost carbon capture from fossil fueled power plants. To realize this technology on an industrial scale, the development of highfidelity simulations is a necessary step to develop a thorough understanding of the CLC process. In this paper, simulations for multiphase flow of the CDCLC process with chemical reactions are performed using ANSYS Fluent computational fluid dynamics (CFD) software. The details of the solid–gas twophase hydrodynamics in the CLC process are investigated using the Lagrangian particletracking approach called the discrete element method (DEM) for the movement and interaction of the solid oxygen carrier particles with the gaseous fuel. The initial CFD/DEM simulation shows excellent agreement with the experimental results obtained in a laboratory scale fuel reactor in coldflow conditions at Darmstadt University of Technology. Subsequent simulations using 60% Fe2O3 supported on MgAl2O4 reacting with gaseous CH4 demonstrate successful integration of chemical reactions into the CFCD/DEM approach. This work provides a strong foundation for future simulations of CDCLC systems using solid coal as fuel, which will be crucial for successful deployment of CDCLC technology from the laboratory scale to pilot and industrial scale projects.