Investigation of oxygen permeation through disc-shaped BSCF ion transport membrane under reactive conditions

The present work investigates the performance of Ba_0.5Sr_0.5Co_0.8Fe_0.2O_3−δ ion transport membrane for separation of oxygen and its simultaneous reaction with gaseous fuels. A 2-D axisymmetric model is considered to investigate the flow and combustion characteristics of methane in a button cell experimental model. A model that includes surface kinetics on the permeate and feed sides together with the bulk diffusion for BSCF membrane is developed and validated well against the experimental results. The effects of reaction on oxygen permeation and combustion characteristics are presented. Firstly, the nonreactive cases are investigated for oxygen permeation only. Later, the effects of increasing CH₄% on the reactivity are explored. Finally, the effect of an increase in the operating temperatures on permeation of oxygen and reactivity are presented and quantified. It is found that the permeation of oxygen increases as the CH₄% is increased in the sweep side because of an increase in the volume flow rates. The reactivity increased with an increase in the CH₄%, however, beyond CH₄ = 2% in the sweep side the amount of unburned CH₄ also increased. It is also indicated that raising the operating temperatures results in shortened flame zones with more concentration in the vicinity of the ITM.