Advanced humid air turbine power plant

Abstract

An advanced humid air turbine power plant capable of suppressing condensation of moisture in a cooling channel, which is provided to cool a high-temperature component of a gas turbine, in a start up stage, a coast down stage, and a load varying state of the gas turbine. In the advanced humid air turbine power plant comprising a compressed air supply line for supplying compressed air generated by a compressor to the high-temperature component of the gas turbine, and a humidified air supply line for supplying humidified air generated in a humidifying tower to the high-temperature component of the gas turbine, the power plant further comprises valves capable of adjusting respective air flow rates in the compressed air supply line and the humidified air supply line. A coolant is switched over from the compressed air to the humidified air in the start up stage and the load increasing stage of the gas turbine, and from the humidified air to the compressed air in the load decreasing stage and the coast down stage, as well as in the event of an abnormality in a humidifying line.

1 .- 9 . (canceled) 
     
     
         10 . A method of operating an advanced humid air turbine power plant comprising a compressor for compressing air, a humidifying tower for humidifying compressed air introduced from said compressor, a combustor for burning fuel and humidified air supplied from said humidifying tower, a gas turbine driven by combustion gases generated in said combustor, a recuperator for performing heat exchange between exhaust gases discharged from said combustor and the humidified air supplied to said combustor, a compressed air supply line for supplying, as cooling air, the compressed air generated by said compressor to a high-temperature component of said gas turbine, and a humidified air supply line for supplying the humidified air added with moisture in said humidifying tower to the high-temperature component of said gas turbine,
 wherein said operating method includes a step of switching over a cooling mode from cooling with the compressed air to cooling with the humidified air in a start up stage or a load increasing stage of said gas turbine.   
     
     
         11 . A method of operating an advanced humid air turbine power plant comprising a compressor for compressing air, a humidifying tower for humidifying compressed air introduced from said compressor, a combustor for burning fuel and humidified air supplied from said humidifying tower, a gas turbine driven by combustion gases generated in said combustor, a recuperator for performing heat exchange between exhaust gases discharged from said combustor and the humidified air supplied to said combustor, a compressed air supply line for supplying, as cooling air, the compressed air generated by said compressor to a high-temperature component of said gas turbine, and a humidified air supply line for supplying the humidified air added with moisture in said humidifying tower to the high-temperature component of said gas turbine,
 wherein said operating method includes a step of switching over a cooling mode from cooling with the compressed air to cooling with both of the compressed air and the humidified air in a start up stage or a load increasing stage of said gas turbine.   
     
     
         12 . A method of operating an advanced humid air turbine power plant comprising a compressor for compressing air, a humidifying tower for humidifying compressed air introduced from said compressor, a combustor for burning fuel and humidified air supplied from said humidifying tower, a gas turbine driven by combustion gases generated in said combustor, a recuperator for performing heat exchange between exhaust gases discharged from said combustor and the humidified air supplied to said combustor, a compressed air supply line for supplying, as cooling air, the compressed air generated by said compressor to a high-temperature component of said gas turbine, and a humidified air supply line for supplying the humidified air added with moisture in said humidifying tower to the high-temperature component of said gas turbine,
 wherein said operating method includes a step of starting to switch over a cooling mode from cooling with the compressed air to cooling with the humidified air in a start up stage or a load increasing stage of said gas turbine when a temperature in the high-temperature component of said gas turbine or an estimated temperature of the high-temperature component of said gas turbine obtained from a temperature at a location substituted for the high-temperature component of said gas turbine rises above a coolant temperature.   
     
     
         13 . A method of operating an advanced humid air turbine power plant comprising a compressor for compressing air, a humidifying tower for humidifying compressed air introduced from said compressor, a combustor for burning fuel and humidified air supplied from said humidifying tower, a gas turbine driven by combustion gases generated in said combustor, a recuperator for performing heat exchange between exhaust gases discharged from said combustor and the humidified air supplied to said combustor, a compressed air supply line for supplying, as cooling air, the compressed air generated by said compressor to a high-temperature component of said gas turbine, and a humidified air supply line for supplying the humidified air added with moisture in said humidifying tower to the high-temperature component of said gas turbine,
 wherein said operating method includes a step of switching over a cooling mode from cooling with the humidified air to cooling with the compressed air in a load decreasing state or a coast down stage of said gas turbine.   
     
     
         14 . A method of operating an advanced humid air turbine power plant comprising a compressor for compressing air, a humidifying tower for humidifying compressed air introduced from said compressor, a combustor for burning fuel and humidified air supplied from said humidifying tower, a gas turbine driven by combustion gases generated in said combustor, a recuperator for performing heat exchange between exhaust gases discharged from said combustor and the humidified air supplied to said combustor, a compressed air supply line for supplying, as cooling air, the compressed air generated by said compressor to a high-temperature component of said gas turbine, and a humidified air supply line for supplying the humidified air added with moisture in said humidifying tower to the high-temperature component of said gas turbine,
 wherein said operating method includes a step of switching over a cooling mode from cooling with the humidified air to cooling with the compressed air in the event of an abnormality in said humidified air supply line.   
     
     
         15 . A method of operating an advanced humid air turbine power plant comprising a compressor for compressing air, a humidifying tower for humidifying compressed air introduced from said compressor, a combustor for burning fuel and humidified air supplied from said humidifying tower, a gas turbine driven by combustion gases generated in said combustor, a recuperator for performing heat exchange between exhaust gases discharged from said combustor and the humidified air supplied to said combustor, a compressed air supply line for supplying, as cooling air, the compressed air generated by said compressor to a high-temperature component of said gas turbine, and a humidified air supply line for supplying the humidified air added with moisture in said humidifying tower to the high-temperature component of said gas turbine,
 wherein said operating method includes a step of switching over a cooling mode from cooling with the humidified air to cooling with the compressed air in the event of an abnormality in said humidified air supply line when at least one of humidity and pressure of the humidified air reduces to a level not higher than a certain threshold.   
     
     
         16 . A method of operating an advanced humid air turbine power plant comprising a compressor for compressing air, a humidifying tower for humidifying compressed air introduced from said compressor, a combustor for burning fuel and humidified air supplied from said humidifying tower, a gas turbine driven by combustion gases generated in said combustor, a recuperator for performing heat exchange between exhaust gases discharged from said combustor and the humidified air supplied to said combustor, a compressed air supply line for supplying, as cooling air, the compressed air generated by said compressor to a high-temperature component of said gas turbine, and a humidified air supply line for supplying the humidified air added with moisture in said humidifying tower to the high-temperature component of said gas turbine,
 wherein said operating method includes a step of switching over a cooling mode from cooling with the compressed air or the humidified air to cooling with an inert gas in a load decreasing stage or a coast down stage.