OXY-TURBINES FOR POWER PLANTS WITH CO2 CAPTURE

摘要

Post-combustion capture is considered the leading option for capture of carbon dioxide (CO2) at natural gas fired power plants, but today there is an increasing interest in the alternative of oxy-combustion turbines, which use recycled CO2 and/or steam as the working fluid. The International Energy Agency Greenhouse Gas R&D programme (IEAGHG) decided to undertake a study that provides an independent evaluation of the performance and costs of several of oxy-turbine plants for power generation. The study includes: 1. Comprehensive literature review of the most relevant systems featuring oxy-combustion gas turbine cycles. 2. Detailed modelling of the gas turbine for the most promising cycles, including efficiency, stage number and blade cooling requirement, using a calculation code developed by Politecnico di Milano. Cycle configuration and optimisation is developed with the support of the main cycle developers, i.e. Clean Energy Systems, Graz University of Technology and NET Power; 3. Technical and economic modelling of promising oxy-turbine power plants, including sensitivity analyses on main technical and financial parameters, so to identify major design and cost criticalities for a viable business case. 4. Levelised costs of electricity generation and costs of CO2 emissions avoidance are calculated and compared with the conventional combined cycle. 5. Assessment of potential for future improvements, including high temperature turbine materials and advanced oxygen membrane separation technologies. 6. High-level evaluation of performance and costs of the most promising markets applications of oxy-turbines, for smaller power plants for Enhance Oil Recovery (EOR) application and integration with industrial power plants. 7. Assessment of oxy-turbine technology applied to coal gasification. The study has demonstrated that oxy-turbine power plants have the technical and economic potential to be a valid alternative to the post combustion capture technology.