Energy & Fuels, Vol.33, No.1, 484-492, 2019
Numerical Simulation of Moderate Temperature Desulfurization in Circulating Fluidized Bed Reactor Considering Sorbent Abrasion
A computational platform was developed to model the desulfurization process in a circulating fluidized bed (CFB) reactor at moderate temperature range (873-1073 K). The model coupled the gas-solid multiphase flow, sorbent particle abrasion, and desulfurization reaction based on MFIX coding. Particle distribution characterization was applied to modify the drag force for gas-solid interaction calculation. The modified model provides a higher accuracy than the widely used homogeneous drag model as validated by the experimental data. Based on simulation results, the abrasion of sorbent particles in CFB leads to about 10% decrease in desulfurization efficiency. The CFB inventory weight is found to have significant influence on the removal efficiency by affecting the multiphase flow field, sorbent particle abrasion, and desulfurization reactions. There exists an optimum bed inventory weight to achieve high efficiency at a low operational cost. In this study, a bed inventory of P-inv = 0.5 was found to be the optimum condition, with the desulfurization efficiency of 59% and the pressure drop of similar to 400 Pa. The established model offers a more accurate way to simulate the desulfurization process and sheds light on the design and operation of a CFB reactor for desulfurization.