Patent ID: 7540154

Claim:
A gas turbine combustor in a gas turbine furnished with a dual fuel combustion low NO x combustor having a pilot nozzle capable of injecting a gaseous fuel and a liquid fuel simultaneously or selectively, and a plurality of main nozzles disposed around the pilot nozzle and being capable of injecting a gaseous fuel and a liquid fuel simultaneously or selectively, wherein the pilot nozzle has a gas nozzle portion for injecting the gaseous fuel, and a liquid nozzle portion for injecting the liquid fuel, adopts an air blast method for the liquid nozzle portion, uses combustion air as air for an air blast, and throws the combustion air at a liquid film formed in the liquid nozzle portion to atomize the liquid fuel by use of a velocity difference between the combustion air and the liquid film, wherein the liquid nozzle portion is formed in an annular shape in order to inject the liquid fuel in an annular liquid film state, and further has a first air blast nozzle portion for producing an air blast along an inner surface of a film of the liquid fuel injected in the annular liquid film state, and a second air blast nozzle portion for producing an air blast along an outer surface of the film of the liquid fuel, and wherein the first air blast nozzle portion is provided at a center of the pilot nozzle, and the combustion air within a turbine casing is supplied to the first air blast nozzle portion via external piping through an air passage penetrating a center of the pilot nozzle.