Method for the introduction of fuel into a premixing burner

1. A method for the introduction of fuel into a premixing burner having a pilot gas feed and a premix gaseous fuel feed for the operation of a gas turbine in the entire load range, in which the pilot gas feed and liquid fuel feed are carried out via a common delivery line in a burner lance provided in the premixing burner and the premix gaseous fuel feed is carried out via side wall shells of the premixing burner, the method comprising:

feeding the premix gaseous fuel;

regulating the feed of the pilot gas so as to enable the setting of a mixture ratio between premix gaseous fuel and pilot gas; and

regulating liquid fuel into the premixing burner via the burner lance in a load range when the pilot gas feed is interrupted;

wherein the pilot gas feed and the liquid fuel feed alternatively pass though a same single fuel feed passage of said common delivery line.

2. The method as claimed in claim 1 , wherein feeding the pilot gas comprises feeding axially to the longitudinal axis of the premixing burner, and further comprising:

intermixing the pilot gas downstream with the premix gas; and

igniting the pilot gas and premix gas.

3. The method as claimed in claim 1 , wherein regulating the feed of the pilot gas and regulating liquid fuel feed are performed alternatively though the same common delivery line.

4. A method for the introduction of fuel into a premixing burner having a pilot gas feed and a premix gaseous fuel feed for the operation of a gas turbine in the entire load range, in which the pilot gas feed and liquid fuel feed are carried out via a common delivery line in a burner lance provided in the premixing burner and the premix gaseous fuel feed is carried out via side wall shells of the premixing burner, the method comprising:

feeding the premix gaseous fuel;

regulating the feed of the pilot gas so as to enable the setting of a mixture ratio between premix gaseous fuel and pilot gas; and

regulating liquid fuel into the premixing burner via the burner lance in a load range when the pilot gas feed is interrupted;

wherein feeding the premix gas and the pilot gas is carried out via said common gas delivery line system.

5. A method for the introduction of fuel into a premixing burner having a pilot gas feed and a premix gaseous fuel feed for the operation of a gas turbine in the entire load range, in which the pilot gas feed and liquid fuel feed are carried out via a common delivery line in a burner lance provided in the premixing burner and the premix gaseous fuel feed is carried out via side wall shells of the premixing burner, the method comprising:

feeding the premix gaseous fuel;

regulating the feed of the pilot gas so as to enable the setting of a mixture ratio between premix gaseous fuel and pilot gas; and

regulating liquid fuel into the premixing burner via the burner lance in a load range when the pilot gas feed is interrupted;

wherein feeding the premix gaseous fuel comprises staged feeding so that the burner shells of the premixing burner are subdivided into sections forming a spatially separate premix gas feed along the burner shells.

6. The method as claimed in claim 5 , wherein, under full-load conditions, feeding the premix gas comprises feeding via all the sections of the burner shells of the premixing burner, and feeding liquid fuel though the burner lance.

7. The method as claimed in claim 5 , comprising, under part-load conditions, at least reducing premix gas feeding into one or more sections of the burner shells of the premixing burner, and feeding a reduced addition of liquid fuel or of pilot gas into the premixing burner via the burner lance.

8. The method as claimed in claim 5 , comprising, under low loads, feeding premix gas into at most one section of the burner shells of the premixing burner, feeding a reduced pilot gas stream into the premixing burner though the burner lance, or both.