Research status and prospect of hydrogen-blended combustion technology of urban terminal natural gas

Blending hydrogen into natural gas is an effective approach to reduce carbon emissions from urban gas appliances and is of great significance for the achievement of dual carbon goal. Hydrogen-blended natural gas has huge application potential in the field of civilian gas appliances. To accelerate the utilization process of hydrogen-blended natural gas at urban terminals, this paper conducts research from the aspects of gas interchangeability theory, application experiment and numerical simulation. Then the feasibility of hydrogen-blended natural gas combustion is elaborated, and the impact of hydrogen blending on the combustion performance, thermal efficiency and pollutant emission of gas stoves and water heaters is discussed. Moreover, the characteristics and application scopes of the combustion reaction mechanism of natural gas are compared. Finally, the main factors restricting the application of hydrogen-blended natural gas combustion technology at urban terminals and the future development trends are pointed out from the aspects of relevant standard and hydrogen blending safety and economy of urban natural gas in China. The following results are obtained. First, the interchangeability between natural gas and hydrogen is primarily influenced by the gas composition and interchangeability index, and the suitable hydrogen blending range of natural gas is 0–20%. Second, hydrogen blending can significantly reduce the carbon emission of natural gas, but further research is required to fully understand the effects on the thermal efficiency, nitrogen oxide emission and adaptability of combustion appliance. Third, furthermore, advanced techniques such as quantum chemistry and machine learning are adopted to understand the mechanism of combustion reaction in numerical simulation of natural gas hydrogen blending. In conclusion, with the construction and development of hydrogen-blended natural gas pipeline, the hydrogen-blended natural gas will exhibit huge potential in the field of end utilization, but meanwhile face many limitations and technical challenges. What's more, a systematic review of the research status of hydrogen-blended natural gas combustion technology is of important and practical significance in promoting the safe and efficient application of hydrogen energy, and provides research ideas and directions for the development of hydrogen-blended natural gas combustion technology. © 2024 Natural Gas Industry Journal Agency. All rights reserved.