Based on the gradient sub-grid scale model and the particle kinetic theory

considering the effect of filtering scale during large eddy simulation

the gas-solid drag coefficient was corrected and the gas-solid two phase flow large eddy simulation model was established.Moreover

the behavior of gas-solid two phase flow was simulated

and the core-annular structure in the riser tube was reasonably predicted.The simulation results were consistent with the experimental results.Furthermore

simulation of the CO2 capture process in the riser tube was conducted

and the gas composition and temperature field were obtained

which can provide references for optimization design of the fluidized bed reactor.