The Impact of Gas Turbine Advancements on Coal IGCC

摘要

Integrated Gasification Combined Cycle (IGCC) has benefited from advancements in each of the four major subsystems that comprise an IGCC plant: gasification, air separation, syngas cleanup and gas turbine combined cycle. Today's challenge-to meet market requirements of cost, reliability, fuel flexibility, efficiency and environmental performance-is being met by process design optimization that capitalizes on the full benefits of these advancements. This paper focuses on the improvements in gas turbine technology that have contributed to the commercialization and leadership of IGCC for clean conversion of coal to power. Environmental performance is a key benchmark for IGCC, whose high marks in environmental performance derive from both the fundamental characteristics of the process and advances in gas turbine technology. The original breed of commercial coal power IGCC projects at Wabash, Indiana, and Polk County, Florida, are still achieving performance in criteria pollutants better than that of recently permitted direct combustion plants. This paper provides comparative data for IGCC as compared to direct coal combustion and highlights the improvements that have provided further enhancements to the environmental performance of IGCC. The future viability of coal depends on the ability and flexibility to meet developing standards in mercury as being considered for 3P legislation. Fuel flexibility has recently emerged as an important metric for choice of power technology. Fuel flexibility provides an effective physical hedge against variations in fuel cost and fuel availability. The robustness of gasification to deal with a wide range of solid and liquid fuels has been demonstrated in IGCC's wide application to coal power, refinery and steel mills. To date, GE gas turbines have accumulated more than 382,000 fired hours on synthesis fuel gas, of which 212,000 hours were fired on syngas derived from coal feedstock. This broad experience, which has been enabled in large part by development in gas turbine technology, serves as a superb entitlement for environmentally superior generation from poor-quality solid fuels. Improvements in gas turbine performance on low heating value syngas have improved the economics of IGCC to where it is a viable commercial contender for new power plants. GE currently has ten IGCC projects in operation, with six more plants either beginning or planned for operation within the next two years. GE continues its investment in the development of gas turbines for coal IGCC.