Highly Efficient Integrated Chemical Looping Gasification Fuel Cell System

Chemical looping process is designed for indirect reactions between fuel and oxidants via exchanging a stream of oxygen carrier particles among separate reactors. It is a promising process that can effectively increase the exergy efficiency for carbonaceous fuel conversion. The chemical looping concept has been widely used for combustion applications in light of its inherent CO₂capture capability. However, its development towards gasification applications, such as hydrogen production, is limited.

Chemical looping gasification (CLG) process can effectively convert carbonaceous fuel such as coal and biomass into hydrogen, and flexibly unite with fuel cell for highly efficient electricity generation with nearly 100% CO₂ capture. This study first generalizes several chemical looping process configurations for hydrogen production. A novel integration between the CLG and the solid oxide fuel cell (SOFC) technology is proposed. The CLG-SOFC system consists of a closed loop between the chemical looping oxidizer and the SOFC anode through the circulation of the gaseous mixture of steam and H₂, which can significantly enhance the electricity generation. Process simulation and exergy analysis confirm the advantages of the proposed process. The results indicate that, through process intensification, the chemical looping gasification strategies have the potential to notably increase process efficiency in the fuel cell system.