Session: 04-06 High Hydrogen II

Paper Number: 128732

128732 - Experimental Study on Stability Enhancement of a Natural Gas GT Burner With Hydrogen Flame Piloting Operated With Simulated Exhaust Gas Recirculation 

Efficient coupling between gas turbine power plants fuelled with natural gas and Carbon Capture and Storage (CCS) units can be achieved by taking advantage of turbine Exhaust Gas Recirculation (EGR). In fact, the efficiency and compactness of CCS units increases with the CO₂ content of the incoming flow. On the other hand, the combustion process has to endure the reduction of overall flame reactivity caused by EGR, resulting in the potential increase of CO and UHC emissions. To counter this fact and to extend the combustor operability window, non-conventional pilot flames can be exploited to improve overall flame stabilization: in the current study the use of local hydrogen pilots was investigated.

A lean-premixed burner for heavy duty Gas Turbine was studied at ambient pressure in a reactive single-cup test rig at the THT Lab of the University of Florence. EGR is replicated at laboratory scale with the addition of CO₂ to the combustion air. In a previous work, the authors analysed the behaviour of the baseline configuration in simulated EGR conditions employing natural gas. This study presents the effect of hydrogen injection through the pilot fuel line with the same burner geometry, in order to highlight the change in performance, in terms of emissions (CO and NOx), stability limits and the onset of thermoacoustic instabilities. Additionally, OH* and CH* chemiluminescence images are presented to analyze the variation in flame topology with the addition of H₂, and thanks also to 2D-PIV flow-field measurements a very detailed analysis can be made. These results will be exploited to validate CFD models that will be employed to optimize the burner design.

Presenting Author: Sofia Galeotti DIEF - Department of Industrial Engineering of Florence - University of Florence

Presenting Author Biography: Sofia Galeotti is a PhD student of the Department of Industrial Engineering of University of Florence, where she got her master’s degree in 2021. Her studies currently focus on combustion diagnostics and heat transfer in gas turbines.

Authors:

Sofia Galeotti DIEF - Department of Industrial Engineering of Florence - University of Florence
Alessio Picchi DIEF - Department of Industrial Engineering of Florence - University of Florence
Riccardo Becchi DIEF - Department of Industrial Engineering of Florence - University of Florence
Gianmarco Lemmi DIEF - Department of Industrial Engineering of Florence - University of Florence
Roberto Meloni Baker Hughes
Giulia Babazzi Baker Hughes
Nicola Giannini Baker Hughes
Bruno Facchini DIEF - Department of Industrial Engineering of Florence - University of Florence
Antonio Andreini DIEF - Department of Industrial Engineering of Florence - University of Florence