Method and gas turbine combustion system for safely mixing H2-rich fuels with air

A method for mixing H2-rich fuels with air in a gas turbine combustion system having a combustion chamber with a burner, comprising:

• providing a first stream of burner air, branched from a stream of compressor air, and a second stream of a H2-rich fuel, wherein the first stream of burner air is not used for liner cooling;
• pre-premixing all of the H2-rich fuel to be injected with the first stream of burner air to produce a pre-premixed fuel/air mixture;
• and
• providing a main air stream, taken from the stream of compressor air and used for liner cooling before entering the burner;
• and
• in the burner, injecting the pre-premixed fuel/air mixture into the main air stream and premixing the pre-premixed fuel/air mixture and the main air to form a premixture within the burner which enters the combustion chamber;
• wherein the pre-premixed fuel/air mixture is injected in an axial direction that is in a cross-flow direction with respect to a direction of injection of the main air stream flow,
• wherein an air excess factor of A>1, is achieved in the premixing in the burner.