(335d) Numerical Simulation of CO2 Removal Process Using Solid Sorbent In a Fluidized Bed: A CFD-PBE Model

Carboncapture process based on solid sorbents is being considered as a potential solution to remove CO₂ from power plant flue gas. The process includes a circulating fluidized bed consisting of a riser as carbonator and a bubbling fluidized bed as regenerator to ensure feasibility of continuous operation of the system.

Experimental data in the literature on fresh, carbonated and regenerated sorbent particles have shown that the sorbent particles size distribution remains almost constant during carbonation and regeneration processes. However, the density of sorbent particle is a function of particle porosity and changes during both sorption and desorption processes. The structural changes in the particles due to the reaction between CO₂ and sorbent lead to the changes in porosity of particles. The focus of this study is to couple the Eulerian-Eulerian CFD model (Arastoopour, 1999 and Benyahia et al., 2000) with the population balance equation (PBE), to account for the evolution of particle density distribution. The model is used to simulate the reactive gas-solid flow inside the riser part of a circulating fluidized bed. The effect of change in particle density distribution on the hydrodynamics and the reaction are investigated.