General Electric Company
METHOD FOR OPERATING A COMBINED CYCLE POWER PLANT AND CORRESPONDING COMBINED CYCLE POWER PLANT

Abstract:

A method for operating a combined cycle power plant includes transferring exhaust gas from a gas turbine to a heat recovery steam generator. Further, the method includes preheating condensate before being fed as feedwater to the heat recovery steam generator. Moreover, the method includes reheating the feedwater in the heat recovery steam generator. The method also includes generating steam in the heat recovery steam generator for a steam turbine, wherein preheating the condensate includes monitoring a temperature of the condensate: if the temperature of the condensate is equal to or above a preset temperature, directing the condensate to a low-pressure economizer of the heat recovery steam generator; if the temperature of the condensate is lower than the preset temperature: directing a first fluid from an intermediate source of the low-pressure economizer to heat the condensate.