Hydrogen deblending on the gas transmission network and gas quality assessment: Sicily case study

This master’s thesis presents a comprehensive study on the deblending of hydrogen within the natural gas transmission network, with a specific focus on the Southern Sicily region. The research investigates the behavior of a gas mixture originating from North Africa, composed of natural gas and green hydrogen in different concentrations, considering a 5%, 10%, and 20% blend. The gas network was modeled using data from the National Transmission System Operator and GIS tools, with topology analysis performed with MATLAB for simulation purposes. The simulations include an examination of the gas mixture’s behavior throughout the pipelines, emphasizing the deblending process at the network’s final nodes, corresponding to delivery points. Separated hydrogen is then progressively reinjected into the network, gradually increasing its concentration as it progresses. The final target is an industrial area with multiple refineries, where a higher hydrogen concentration is desired. For each blending scenario, an analysis is conducted to assess the hydrogen accumulation and the quality of the gas, including considerations of relative density, Wobbe Index, and Higher Heating Value, ensuring compliance with relevant standards. This research has the aim of contributing to our understanding of the integration of hydrogen into existing natural gas infrastructure and its potential for enhancing the sustainability of energy transportation networks.