Development and Application of a Method for Evaluating Hydrogen Permeability and Porosity of Salt Rocks

Summary The pressure pulse decay (PPD) method is widely used for measuring permeability in tight porous media. However, it can overestimate the permeability of salt rocks to hydrogen due to gas leakage at the rock-sleeve interface, caused by hydrogen’s high diffusivity. In addition to this, the method is time-consuming, particularly for tight materials such as salt rocks, and the error in permeability measurements can be as high as 60%, making it less reliable for accurate assessments. We present a modified experimental setup and analytical approach for fast and more accurate determination of permeability and porosity of salt rocks with hydrogen. Our results demonstrate that this modified experimental configuration significantly improves the accuracy by at least 10 times and reduces the duration of experiments 4 times for measuring permeability and porosity compared with the conventional PPD method. We validated our experimental and analytical methodology through permeability and porosity measurements on salt rock samples sourced from the Lotsberg Formation (LSF) in Fort Saskatchewan, Alberta, Canada.