Daniel Palmowski

Co-authors; Daniel Palmowski, Adrian Kleine, Thomas Hantschel Terranta GmbH, Aachen, Germamy Exploration activity for natural hydrogen has grown significantly in recent years. The geologic concepts and processes required for natural hydron to produce economic hydrogen accumulations are being more and more refined to support the efforts to explore for geologic hydrogen resources. The hydrogen system concept, adopted from the petroleum system approach, is now being applied for many exploration projects around the world. New and effective tools to model the hydrogen system are being developed. Adopting some of the workflows form hydrocarbon and combining them with those of mineral exploration, two- and three-dimensional reactive transport modeling offers an effective approach to test our hypothesis and concepts for consistency and efficiency. The modeling of hydrogen generation, migration and accumulation requires however several new modeling technologies and as well as a better understanding of how the generated hydrogen migrates through the subsurface. Any “working” hydrogen system requires efficient hydrogen expulsion from a source rock. Generation via serpentinization or radiolysis can only lead to efficient hydrogen expulsion if the generated hydrogen is transported out of the source rock to prevent a thermodynamic equilibrium situation within the source rock. Therefore, the key to modeling hydrogen systems is describing and quantifying the flow of water in the subsurface. Water accessibility is critical for the generation processes (serpentinization or radiolysis), the water-flow rate is critical to understand the transport of hydrogen and hence the effective expulsion from the source rocks. An extension to the simple Darcy flow formulation of the water flow is required to address the complexity of flow drivers (density driven flow/convection) and the complexity of hydrogen transportation and migration (advective and diffusive transport, free-phase flow). To solve such problems using numerical methods requires smart and efficient grids, to not only deliver the numerical base for solving complex differential equations. The grids need to be capable of representing the needed geometric complexity of the geological models. Additionally, the modeling of convection and advective transport adds new and different scales, in both space and time, to the model. We will present and illustrate the status quo of Hydrogen Systems Modeling based on real case studies. Modeling the flow rates of water in the subsurface on the needed scales and accuracies the combination with reactive flow modeling capabilities opens the capabilities to quantitatively assess hydrogen systems to de-risk exploration projects.