Advanced Concepts for Direct-Fired Cycles

In directly-fired supercritical CO2 power cycles, oxygen and fuel (either syngas or natural gas) are combusted, forming a stream of primarily supercritical CO2 and steam which is used as the working fluid in the power cycle. The higher temperature and pressure conditions of these cycles give the potential for even higher cycle efficiencies, while the process produces CO2 for either sequestration or reuse purposes. The R&D within this key technology aims to develop high-pressure and high-temperature oxy-fuel combustors to be used with CO2 as the diluent, as well as the integration of the combustors with the turbomachinery, for use in directly fired sCO2 power cycles. The challenges associated with this R&D include understanding combustion kinetics and dynamics under these conditions, combustion stability, flow path design, thermal management, pressure containment, and definition of turbine inlet conditions.

Southwest Research Institute’s Autoignition-Stabilized Combustor Concept for Direct Fired
Supercritical Oxy-Combustion Cycle

NETL is supporting several projects in the area of sCO2 oxy-fuel combustion R&D. Additionally, the University Turbine Systems Research Program (UTSR) addresses scientific research to develop and transition advanced turbines and turbine-based systems that will operate cleanly and efficiently, focusing on research in the areas of combustion, heat transfer/aerodynamics, and materials to support the Advanced Turbine Program goals. Within the UTSR Program, sCO2 cycle oxy-fuel combustion projects are being funded.

Georgia Tech shock tube for combustion studies in sCO2
(click to enlarge)