Hydrogen fuel supply system and re-heat gas turbine combustion

Carbon Capture and Storage (CCS) based on the pre-combustion routine involves a fuel supply and gas turbine combustion system which must handle a fuel with a very high content of Hydrogen. This might cause problems related to ignition and auto-oxidation in the piping in addition to thermo-acoustic instabilities, flash back and increased emissions in the gas turbine. In this work it is found that for typical fuel compositions problems with self ignition and auto-oxidation in the fuel supply system is avoided if the mixture temperature is kept below 400°C and the fraction of Oxygen in the fuel does not exceed 3%. Furthermore it is shown that even a reheat combustor can be fuelled with up to 70% Hydrogen and 30% Nitrogen as diluent at full load without problems with combustion instabilities or NOx emissions when inline fuel injection is used together with appropriate mixing devices.