**Researchers from the University of Stuttgart and the German National Metrology Institute (PTB) have conducted a study on the impact of hydrogen addition on the thermodynamic properties of a high-calorific natural gas mixture. Their findings, published in the journal Fluid Phase Equilibria, provide valuable insights for the energy industry as it explores the integration of hydrogen into existing natural gas infrastructure.**
The study focuses on the effects of adding up to 20% hydrogen by volume to a natural gas mixture that contains significant amounts of ethane and propane. As the energy sector seeks to decarbonize, injecting hydrogen into the natural gas grid is seen as a promising strategy. However, to ensure safe and efficient operations, it is crucial to understand how hydrogen affects the thermodynamic properties of natural gas.
The researchers prepared three mixtures for their experiments: a base natural gas mixture and two variants enriched with 10% and 20% hydrogen. They then measured the density of these mixtures at temperatures ranging from -13°C to 77°C and pressures up to 20 MPa using a precise densimeter. The team compared their experimental data with predictions from three widely-used equations of state: AGA8-DC92, GERG-2008, and an improved version of GERG-2008.
The results showed that all three models performed better for methane-dominant mixtures than for those containing heavier hydrocarbons like ethane and propane. This finding highlights the need for more accurate equations of state that can reliably predict the behavior of hydrogen-enriched natural gas mixtures with significant amounts of heavier hydrocarbons.
For the energy industry, this research provides essential data for the safe and efficient integration of hydrogen into natural gas grids. Accurate density measurements and improved equations of state will enable better pipeline design, flow calculations, and overall system optimization. As the sector continues to explore hydrogen as a means of decarbonization, studies like this one will play a crucial role in ensuring the smooth transition to a lower-carbon energy system.
Source: Fluid Phase Equilibria, Volume 548, November 2021
This article is based on research available at arXiv.