Technical Field
The present invention relates to a gas turbine combustor and, more particularly, to a dual-fuel burning gas turbine combustor which is a multi-burner type gas turbine combustor including a plurality of burners and corresponds to both a liquid fuel and a gaseous fuel.
Background Art
Due to a recent critical demand for electric power in the power generation business, there is an increasing need for the use of various types of fuels including liquid fuels, which can be relatively easily supplied, so gas turbine power generation facilities that use a liquid fuel combustor are demanded.
An available gas turbine combustor uses a pre-evaporation/pre-mixing combustion method, in which a liquid fuel is mixed with air before the fuel is burned from the viewpoint of environment protection.
Technologies related to a dual-fuel burning gas turbine combustor that corresponds to both a liquid fuel and a gaseous fuel are disclosed in Japanese Laid-open Patent Publication Nos. 2007-327338 and 2003-148734.
The technology disclosed in Japanese Laid-open Patent Publication No. 2003-148734 relates to a gas turbine combustor in which a diffusive combustion burner is placed at the center and a plurality of pre-mixing combustion burners, each of which has a cylindrical mixing chamber to mix a fuel with combustion air, are provided around the outer circumference of the diffusive combustion burner.
The diffusive combustion burner disposed in the gas turbine combustor disclosed in Japanese Laid-open Patent Publication No. 2003-148734 has air holes to swivel combustion air. Combustion gas at a high temperature is spread toward the outer circumferential to use it as a firing source of the pre-mixing combustion burner, making its combustion more stable.
The pre-mixing combustion burner disposed in the gas turbine combustor has a liquid fuel nozzle substantially at the center of the axis and the mixing chamber is disposed downstream of the liquid fuel nozzle.