Patent ID: 6679047
Filing Date: 2004-01-20
Classification: F01K,F02C,F05D,Y02E

Abstract:
A combined cycle gas turbine system comprising:a steam turbine having a high pressure turbine, an intermediate pressure turbine and a low pressure turbine; a condenser for condensing exhaust steam of said low pressure turbine of said steam turbine, a gland steam condenser being connected to said condenser; a gas turbine having a compressor for compressing air, a combustor for combusting fuel with air from said compressor and a turbine for expanding high temperature combustion gas from said combustor for driving a generator, said turbine including a moving blade and a stationary blade; a cooling steam system for cooling said combustor, said stationary blade and said moving blade of said turbine; and a waste heat recovery boiler including a feed water heater, an intermediate pressure superheater and a reheater, said waste heat recovery boiler being fed exhaust gas from said gas turbine so that condensed water coming from said condenser through said gland steam condenser can be heated and vaporized to supply steam to said high pressure turbine, said intermediate pressure turbine and said low pressure turbine; wherein said cooling steam system comprises a moving blade cooling system having a water spray rate control valve leading high pressure water from said feed water heater, a demineralizer connected to said water spray rate control valve and a water sprayer connected to said demineralizer for spraying the high pressure water into a passage leading cooling steam from an outlet of said high pressure turbine into said moving blade of said gas turbine, a stationary blade cooing system for leading a portion ofthe steam from the outlet of said high pressure turbine into said stationary blade of said gas turbine, and a combustor cooling system fed with steam from said intermediate pressure superheater for cooling a transition piece of said combustor, where steam from said moving blade cooling system is recovered into said reheater and steam from said stationary blade cooling system and said combustor cooling system is recovered into an inlet of said intermediate pressure turbine.