Steam turbine plant

A steam turbine plant, comprising:

• a boiler that generates steam;
• a steam turbine driven by the steam generated in the boiler;
• a feedwater system that recovers the steam exhausted from the steam turbine and supplies the steam to the boiler as feedwater, wherein the feedwater system includes a steam condenser connected to the steam turbine;
• a superheating combustor provided between the boiler and the steam turbine,
• wherein fuel originated from a hydrocarbon fuel and an oxidizer are mixed with the steam generated in the boiler and combusted in the superheating combustor to increase the temperature of the steam;
• and
• a compressor coupled with the steam condenser which separates noncondensing gas from the steam condenser.

In a steam turbine plant having a boiler that generates steam, a steam turbine driven by the steam generated in the boiler which utilizes coal, a feedwater system that recovers the steam exhausted from the steam turbine and supplies the steam to the boiler as a feedwater;

• a method for operating said steam turbine plant comprising:
• feeding said steam from said boiler to a superheating combustor;
• feeding a hydrocarbon fuel and an oxidizer to said superheating combustor;
• controlling a quantity of heat of the hydrocarbon fuel up to about 40 percent of a total heat quantity of the fuel and the coal utilized in the plant;
• combusting said hydrocarbon fuel and said oxidizer in said superheating combustor with said steam from said boiler to produce super high temperature steam;
• and,
• feeding said super high temperature steam to said steam turbine.

In a steam turbine plant having a boiler that generates steam, a steam turbine driven by the steam generated in the boiler, a feedwater system that recovers the steam exhausted from the steam turbine and supplies the steam to the boiler as a feedwater;

• a method for operating said steam turbine plant comprising:
• feeding said steam from said boiler to a superheating combustor;
• feeding a hydrocarbon fuel and an oxidizer to said superheating combustor;
• combusting said hydrocarbon fuel and said oxidizer in said superheating combustor with said steam from said boiler to produce super high temperature steam;
• feeding said super high temperature steam to said steam turbine;
• recovering the steam exhausted from the steam turbine in a steam condenser;
• and
• compressing noncondensing gas which is separated from the steam condenser.