Nicolai Thüns, M.Sc.

 

H2 - ReacT - In Cooperation with LEK

In cooperation with LEK, Institute for Geology and Geochemistry of Petroleum and Coal, Dr. Bernhard Kroos.

The project H2_ReacT, as well as the follow-up project H2-ReacT 2 (start 01.09.2020; duration 2 years), are guided by the cooperation of the RWTH Aachen University, the Helmholtz Centre Potsdam German Research Centre for Geosciences (GFZ) and the Federal Institute for Geosciences and Natural Resources (BGR) Hannover. The focus of those projects lays on the fundamental description of petrophysical, mineralogical-geochemical and biological processes taking place in potential geological underground storage sites for molecular hydrogen (H2). At the moment there is a gap in scientific data allowing to predict the long-term behavior of geological underground storage sites in an appropriate way. The biggest uncertainties concerning the reactive transport of H2 in a potential storage formation are reliable rate constants for relevant redox-reactions, data on the hydrogen permeability of potential reservoir seals as well as data on the changes of permeability due to microbial activity.

In the previous project H2_ReacT (01.07.2017 to 30.06.2020) the institutes “Clay and Interface Mineralogy” (RWTH-CIM) and “Geology and Geochemistry of Petroleum and Coal” (RWTH-LEK) experimentally determined kinetic parameters for the reaction system H2-hematite (Fe2O3) (Thüns et al., 2019). Additionally, changes of permeability due to the consumption of H2 associated to microbial activity was examined for relevant storage and seal formations. In this first project the cooperation partners focused also on geochemical reactions (BGR-GeoC) and microbial processes (BGR-MiBi) as well as on the solubility of H2 in saline fluids (GFZ).

The follow-up project H2_ReacT 2 continues to process open questions concerning the fundamental description of reactive transport processes of H2 in the geological underground. Based on the knowledge of the past project the future research aims are focused on the following topics:

1. Coupled redox processes of H2 with iron oxides with focus on solution-precipitation reactions and the formation of reaction fronts (RWTH-CIM, BGR-GeoC , RWTH-LEK)
2. The influence of solution and diffusion rates on the spacial distribution and the availability of hydrogen for reactive processes during storage site operations (GFZ)
3. Conditions and impact of microbial H2 consumption in geological storage formations (e.g. methanation, sulfate reduction, formation of biofilms) (BGR-MiBi, RWTH-LEK)