Higher concentrations of hydrogen in natural gas and their impact on industrial combustion systems

In recent years, the power-to-gas approach has been proposed as a promising way to store large amounts of electricity by producing hydrogen via electrolysis and then possibly inject it into the natural gas grid. As a consequence, end users of natural gas across all sectors could be confronted with higher and fluctuating concentrations of H2 in the locally available natural gas and there are concerns, particularly in the thermal processing industries, how these changes in the fuel composition might impact the product qualities, efficiencies and NOX emissions of gas-fired manufacturing processes. In a German research project, Gas- und Wärme-Institut Essen e. V. (GWI) investigated the impact of higher and fluctuating hydrogen contents (up to 50 vol.-%) on a variety of industrial burner systems, using both simulation and experimental methods. The effects on operational aspects such as combustion behaviour, flame monitoring and pollutant emissions were analyzed.