A Numerical and Experimental Analysis of Emissions from an Industrial Combustor Fueled with Methane–Hydrogen Blends

The injection of green hydrogen in the natural-gas infrastructure is an efficient option for the transport, consumption, and storage of large amounts of renewable energy, helping to overcome the balancing problems of the electricity network as well as to decarbonize the energy use in different sectors (e.g., civil, transport, industry). However, the injection of H2 can determine relevant implications on the safety and integrity of pipelines and of the main components of the networks, as well as unwanted issues in the combustion process. In this paper, the effects of hydrogen injection in methane up to 35%vol on an industrial combustor under lean conditions have been evaluated from a theoretical and experimental point of view. In particular, the emissions of the combustion process have been investigated through experimental analysis and numerical simulation of key parameters (e.g., flame temperature, flame stability, flame speed, etc.) and the flue-gas analysis (e.g., flue-gas temperature, emissions of CO, NOx, etc.). From the point of view of the combustion process, the obtained results show that no issues occur from the injection of hydrogen into methane up to 23%vol under lean conditions.