Computational fluid dynamics modeling and simulations of fluidized beds for chemical looping combustion

Efficient carbon capture and storage technologies are needed to address the rising carbon emissions from power generation using fossil fuels that have been linked to global warming and climate change. One such technology that shows great promise is chemical-looping combustion (CLC) due to its potential for high-purity carbon capture at low cost. To realize this technology on an industrial scale, the development of high-fidelity simulations is a necessary step to develop a thorough understanding of the CLC process. This chapter summarizes recent developments in reactor-level simulations of CLC using computational fluid dynamics (CFD) coupled with the Discrete Element Method (DEM) for tracking the individual oxygen carrier particles inside a CLC system. A coupled CFD-DEM model of a CLC reactor is presented that incorporates chemical reactions along with the multiphase flow simulation. Simulations are also conducted of a binary particle bed associated with a coal-direct CLC system consisting of coal (represented by plastic beads) and oxygen carrier particles and validated against an experimental riser-based carbon stripper. The work presented in this chapter provides valuable insights into the various process and design optimizations critical to the efficient operation and performance of the CLC process.