PREMIX BURNER FOR A GAS TURBINE ASSEMBLY FOR POWER PLANT SUITABLE TO BE FED WITH COMMON AND HIGHLY REACTIVE FUELS, METHOD FOR OPERATING THIS BURNER AND GAS TURBINE ASSEMBLY FOR POWER PLANT COMPRISING THIS BURNER

A premix burner for a gas turbine assembly for a power plant, the premix burner (34) comprising: a swirler (35), having an upstream end fed by compressed air and a downstream end, the swirler being configured for swirling the air flow and being provided with premix injection nozzles (36) connected to a first gas fuel source; a casing (37) having a first end connected to the downstream end of the swirler (35) and a second end; a pilot lance (38) axially extending the swirler (35) and having a downstream end housed in the casing (37), the downstream end of the pilot lance (38) being provided with pilot injection nozzles connected to the first gas fuel source; a collar (39) having upstream end connected to second end of the casing (37) and a downstream end facing a combustion chamber. The collar (39) is provided with downstream injection nozzles (40) connected to a second gas fuel source; the second gas fuel source being a highly reactive H2-based fuel gas source.