COMBINED GENERATION PLANT AND ITS OPERATING METHOD

摘要

PROBLEM TO BE SOLVED: To provide technology for preventing the corrosion of a preheater by effectively controlling the temperature of exhaust gas. SOLUTION: Pressure supply lines 40 are provided between each of a medium pressure drum 33b and a high pressure drum 33c and a low pressure drum 33a for bleeding air from the medium drum 33b and the high pressure drum 33c to the low pressure drum 33a to increase pressure in a whole low pressure line La, whereby the heat absorbing amount of an evaporator 34a provided on the upstream side in the flowing direction of exhaust gas beyond the preheater 30 is reduced in an exhaust heat collecting boiler 25 using the exhaust gas from a gas turbine 21 as a heat source. COPYRIGHT: (C)2004,JPO