Patent ID: 6089012
Filing Date: 2000-07-18
Classification: F01K,F02C,F05D,Y02E

Abstract:
A steam cooled gas turbine system in a combined power plant which comprises a combination of a gas turbine plant and a steam turbine plant, and an exhaust heat recover boiler for generating steam turbine driving steam by utilizing exhaust heat from a gas turbine, the improvement comprising:conduits for supplying a gas turbine blade cooling steam and combustion exhaust cooling steam bled from an outlet of steam turbine to a fuel heater for heat exchange with fuel;a source of water mixable with the respective cooling steams for controlling the temperature of the cooling streams;a controller for supplying the temperature controlled cooling steams to a cooling portion for cooling blades of the gas turbine; andthe blade cooling steam that has left the cooling portion being recovered into an intermediate area of a reheater, while the exhaust cooling steam that has left the cooling portion is recovered into a inlet of the steam turbine.