Design of a 1MW Direct-Fired Oxy Combustor for sCO2 Power Cycles

Abstract

Direct-fired super-critical carbon dioxide (sCO2) power cycles are a potential method for efficiently capturing nearly all of the CO2 emissions from burning fossil fuels. Direct-fired sCO2 cycles require a very high degree of recuperation, which in turn means that the inlet temperature to the combustor is significantly higher than would typically be seen in a similar gas turbine combustor. Previous efforts have shown that combustor inlet temperatures of around 700°C at 200 bar are to be expected for a cycle with around 1200°C combustor exit temperatures. The project team led by Southwest Research Institute is in the process of building and commissioning a 1MW scale direct-fired sCO2 oxy combustor. The test rig at SwRI uses laser ignition and advanced optical access to monitor combustion and characterize behavior. This paper will detail some of the challenges associated with the design and fabrication of the combustor and sCO2 power loop. These obstacles include thermal management, water generation, and constituent monitoring. The first ever unsteady simulations of this type of combustor were conducted as part of the design process. A presentation of the test rig layout, design considerations, and integration challenges will be covered.