Alstom’s Chemical Looping Combustion Technology for CO<Sub>2</Sub> Capture for New and Retrofit Coal-Fired Power Plants

Abstract

Cold Flow Modeling (CFM) is a critical tool to understand solid transport, corresponding process stability, and the impact on the performance of the LCL-CTM technology. As such it plays a central role in the development of the LCL-CTM process and deserves a standalone report in the final reporting on Phase II of the collaboration with DOE under award DE FE0009484. The 40-Foot Cold Flow Model (CFM) was constructed before the 3 MWth Prototype. The purpose of the CFM is to: develop design and operational information to design the Prototype help resolve solids transport problems that occur with the Prototype provide Prototype operator training. This report provides a review on the use of the CFM to achieve better understanding, design, and operation of solid transport for the LCL-CTM technology. Significant progress was made by iteratively designing, operating, and testing between the CFM and the Prototype scale. Fundamental understanding of the transport of reactive solids was acquired based on the reported effort. Unfortunately, the technical gaps identified for Phase II of the LCL-CTM technology development could not all be eliminated and the transport of solids under high fuel load remained unstable at the Prototype scale. The nature of the iterative learning going back and forth between CFM and Prototype scale became cost-prohibitive and forced the project to pivot at a relatively late date in the project. The LCL-CTM process switched from a Transport reactor design to a Bubbling Fluidized Bed (BFB) design in order to successfully achieve all process criteria but at the 100-kWth scale to accommodate the residual funding. The CFM remains a very relevant tool for future LCL-CTM process development. While the LCL-CTM technology still must be demonstrated under scale up conditions (and the success of the BFB testing would push to scale up in that configuration), the CFM will remain a preferred tool for troubleshooting and reducing the technical gaps of LCL-CTM.