초록 ▼

Gas turbine combined cycle system is improved to enhance gas turbine efficiency and combined efficiency by effecting steam-cooling of combustor tail tube and turbine blades. In the combined cycle system comprising; gas turbine (8) having generator (1), compressor (2), combustor (3), blade cooling ai

Gas turbine combined cycle system is improved to enhance gas turbine efficiency and combined efficiency by effecting steam-cooling of combustor tail tube and turbine blades. In the combined cycle system comprising; gas turbine (8) having generator (1), compressor (2), combustor (3), blade cooling air cooler (4), fan (5) and turbine (6); steam turbine (29) having high pressure turbine (21), intermediate pressure turbine (22) and low pressure turbine (23); and waste heat recovery boiler (9), saturated water of intermediate pressure economizer (12) is partially led into fuel heater (30) for heating fuel and the water cooled thereby is supplied to feed water heater (10). Steam of intermediate pressure superheater (16) is led into the combustor tail tube for cooling thereof and the steam is then supplied to inlet of the intermediate pressure turbine (22). Steam of outlet of the high pressure turbine (21) is led into the turbine (6) for cooling blades thereof and the steam used for cooling stationary blades is supplied to the inlet of the intermediate pressure turbine (22) and the steam used for cooling moving blades is supplied to reheater (20). Thus, the efficiency is enhanced.

대표청구항 ▼

1. 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

1. 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.