Modeling and Validation of Flow and Heat Transfer Phenomena for Coal-Fired Boilers for Indirectly-Heated Supercritical Carbon Dioxide Power Cycles

The proposed effort is for integration of a coal-fired boiler with the primary heat exchanger of indirectly heated supercritical carbon dioxide power cycle. There is significant gaps in the current state-of-the-art knowledge on validated correlations for carbon dioxide heat transfer for a wide range of channel sizes, shapes, flow velocities, and heat fluxes. This lack of knowledge, combined with specific operational peculiarities of a supercritical carbon dioxide power cycle, makes design and optimization of boiler integrated with power cycle primary heat exchanger as a major gap and is the focus of this proposal. Final product which can be the outcome of these proposed efforts will lead to an optimized PC boiler implemented in an indirect fired sCO2 cycle. This will be an important step forward toward commercializing coal fired sCO, cycles. This will directly contribute to DOE’s Coal FIRST initiative. SE is developing modeling and design tools for sCO2 coal boiler that will be fully validated against testing at realistic conditions, that (1) provide design optimized for minimal exergy loss, and tube life, (2) provide life estimate for the entire PC-boiler under prescribed operational transients. To accomplish this, SE at its partners at the University of Central Florida (UCF) obtain high-quality data and correlations for the CO2 side heat transfer characteristics at conditions representative of those in coal-fired furnaces. This data will give the industry confidence in designing commercial scale equipment. The primary objective of this Phase I work is to model, validate and then create an optimization framework for design and optimization of a coal-fired boiler for an indirect-fired supercritical carbon dioxide (SCO2) cycle. In addition to CO2 heat transfer data, which is cornerstone of this project, the flue gas side of heat transfer will be modeled and then used to create a one-dimensional analysis code in IDAES for the CO2 primary heat exchanger integrated with boiler. The proposed efforts will help to develop the next generation of coal plants. Even though coal usage for power generation has decreased within the USA, coal usage in some parts of the world has increased significantly. Under this scenario, the proposed project can help US OEM’s to support those increased coal usages with environmentally friendly, and yet cost-effective, solution.