A Multiple-Compartment Ion-Transport-Membrane Reactive Oxygen Separator

Oxy-combustion using an integrated oxygen ion-transport membrane (ITM) could substantially improve the thermodynamic performance of power plants with carbon capture and sequestration (CCS). In a reactive ITM, fuel is burned inside the unit to enhance the oxygen partial pressure driving force, thus reducing the reactor membrane material required, compared to nonreactive ITM applications. The multiple-compartment reactive ion-transport membrane (MCRI) concept proposed herein mitigates key drawbacks of the reactive ITM and improves the performance by dividing the overall ITM into stages with individual input streams in a serial arrangement. This arrangement enables more-effective thermal management of the ITM and, thus, higher average oxygen permeation flux. Consequently, the pressure drop and size (volume/surface area) are significantly reduced, compared to conventional reactive ITM designs. The MCRI is modeled and simulated in ASPEN Plus, using multiple instances of an intermediate-fidelity ITM model that captures all relevant physical processes. The simulation results indicate that a power cycle using an integrated MCRI could significantly improve the economic viability of oxy-combustion CCS power plants.