COMBINED CYCLE POWER PLANT HAVING IMPROVED COOLING AND METHOD OF OPERATION THEREOF

摘要

An improved combined cycle power plant (10) having a plurality of kettleboilers (30, 31, 32) used in sequence for cooling the compressed air beingdirected via line (29) to cool portions of the gas turbine (20). The kettleboilers remove heat from the compressed air and produce a plurality of steamflows in lines (70, 71, 73) at pressures in parallel with the heat recoverysteam generator (41, 42, 43) steam flows. Steam in line (72) for cooling otherportions of the gas turbine is maintained at a very high level of purity byproviding a high rate of blowdown through line (65) from the steam drum (45)providing the steam. Heat from the blowdown flow is directed to heat exchanger(66) to heat incoming fuel gas from source (26), or alternatively to heat thecondensate via line (74) during periods of fuel oil operation.