Dynamic Simulation of Chemical Looping Combustion in Packed Bed Reactors

Abstract

Abstract Chemical looping combustion (CLC) is a promising energy conversion technology for fossil fuel combustion with inherent carbon dioxide separation and minimum energy and cost penalties for CO 2 capture. Designing and setting the optimum operating conditions for the CLC reactors are important steps to be taken before implementing the process on an industrial scale. In this work, a dynamic mathematical model has been developed to simulate packed bed reactors used in a methane-based chemical looping combustion process with iron-based oxygen carrier. The air and fuel reactor models were interconnected with the models describing the purge steps of the process to highlight the dynamic behaviour of the entire process. The developed model was used to predict (in space and time): gas flow profile, gas composition distribution, behaviour of oxygen carrier and temperature profiles inside the air and fuel reactors. The simulation results of the 1D model had been compared with the experimental data published in the literature. The model developed is able to describe the process very accurately, for a wide range of gas flow rates. Increasing the flowrate by 20% of the base value lead to a shorter time in which the process achieved stationarity by approximately 300 s (for oxidation step). During the reduction step, the reaction rate decreases very fast at a solid conversion above 85%.