Currently, pressurized fluidized bed combustion (PFBC) combined cycle power plants apply multiple stages of cyclones to clean the combustion products prior to turbine expansion, and rugged, inefficient expanders are required for this dirty-gas duty. The turbine inlet temperature is limited to the fluid bed combustor temperature, about 843°C (1550°F), so the plant thermal efficiency is relatively low. The development of hot gas filtration and coal-gas topping for PFBC combined cycles is the next step in the evolution of PFBC, and will result in the use of modern, high-efficiency combustion turbines in PFBC applications as well as plant thermal efficiencies up to 47% (HHV). Westinghouse is developing integrated combustion turbine systems that interface with PFBC plants and incorporate the functions of hot gas filtration, alkali vapor removal, topping combustion, hot gas piping and control, and turbine compression and expansion. This paper reports on the engineering considerations made by Westinghouse for these integrated combustion turbine systems and summarizes the current development activities and status.

This content is only available via PDF.