Patent ID: 6389797
Filing Date: 2002-05-21
Classification: F01K,F02C,Y02E

Abstract:
A gas turbine combined cycle 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 the low pressure turbine of the steam turbine; a gas turbine having a compressor for compressing air, a combustor for combusting fuel with the air coming from the compressor and a turbine for expanding a high temperature combustion gas coming from the combustor for driving a generator; a cooling system for cooling the combustor and blades of the turbine; and a waste heat recovery boiler having components including a feed water heater, an intermediate pressure economizer, a low pressure superheater, an intermediate pressure superheater, a high pressure superheater, a high pressure evaporator and a reheater, and being fed with exhaust gas of the gas turbine so that condensed water coming from the condenser is heated and vaporized via the components of the waste heat recovery boiler for supplying steam to the high pressure, intermediate pressure and low pressure turbines, respectively; wherein there is provided a fuel heater for heating the fuel before the fuel enters the combustor, wherein saturated water coming from the intermediate pressure economizer of the waste heat recovery boiler is partially diverted to flow to the fuel heater for heating the fuel, and wherein the saturated water so used for heating the fuel is supplied to an inlet of the feed water heater.