Remodeling method of combined cycle plant, distribution duct, and combined cycle plant

摘要

A remodeling method of a combined cycle plant including gas turbines; heat recovery steam generators provided corresponding to number of the gas turbines and configured to recover heat of flue gas discharged from the gas turbines and produce steam by the recovered heat; ducts configured to guide the flue gas from the gas turbines toward the respective heat recovery steam generators; and a steam turbine configured to be rotationally driven by the steam produced by the heat recovery steam generators. The remodeling method of a combined cycle plant includes: removing gas turbines and ducts; installing, in place of the two gas turbines, a new gas turbine that is higher in efficiency and smaller in number than the two gas turbines; and installing, in place of the ducts, a distribution duct configured to distribute and guide flue gas from the new gas turbine to two heat recovery steam generators.