Raman spectroscopy experimental mixed gas H2-CH4-brine EOS calibration for hydrogen storage
Project lead
Dr Julien Bourdet, julien.bourdet@csiro.au
Lead researchers
Lead investigator and experimental lead: Julien Bourdet, julien.bourdet@csiro.au;
Modelling lead: Chris Green, chis.green@csiro.au
Challenge
The assessment of geological storage of hydrogen in the Australian subsurface either in depleted oil and gas reservoirs or saline aquifer is dependent on effective reservoir simulation tools.
Raman spectrometer
What we are doing
CSIRO developed an equation of state (EOS) for hydrogen gas mixtures (e.g. hydrogen-methane) and brine, that can be used to model injection and withdrawal cycles for underground storage of hydrogen. However, this EOS is based on limited published experimental datapoints for gas mixtures such as H2-CH4. To improve the numerical predictions of underground hydrogen storage, more experimental datapoints for these mixtures at typical reservoir conditions are required to improve and validate the EOS.
Experiment apparatus
An experimental apparatus for measuring in-situ gas solubility datapoints for the H2-CH4-H2O-NaCl system at a range of pressure and temperature conditions relevant for underground storage has been created, employing in-situ Raman spectroscopy measurement in a high pressure optical cell with silica capillary tubing. The cell requires very low volumes of gas that effectively resolves commonly met laboratory health and safety issues.
The new calibration dataset acquired for the system H2-CH4-H2O and their implementation in a new EOS will provide CSIRO a unique position to model H2 behaviour and fate in depleted oil and gas reservoirs. This will complement our existing capability to predict underground storage of H2 and CO2 in saline aquifers via benchmark reservoir simulations.
Outcomes to date
The constructed apparatus delivered critical data between 20oC and 250oC and at pressures between 1 to 300 bar. The aqueous fluid used was pure water and the intention is to study later the effect of salt.
Experimental gas solubility in pure water for a mixture of 15% hydrogen and 85% methane at different temperatures and pressures
Lessons learned
From an experimental viewpoint, the ability of H2 to dissolve into the silica media of the optical cell at high pressure was an issue to acquire “clean data” in the water phase. We solved the issue by using larger internal diameter tubes to avoid having silica into the measurement volume.
Project finish date
December 2022
Relevant project publications
Bourdet, Julien; Delle Piane, Claudio; Wilske, Cornelia; Mallants, Dirk; Suckow, Axel; Questiaux, Danielle; Gerber, Christoph; Crane, Punjehl; Deslandes, Alec; Martin, Laure; Aleshin, Matvei. Natural hydrogen in low temperature geofluids in a Precambrian granite, South Australia. Implications for hydrogen generation and movement in the upper crust. Chemical geology. 2023. 18p. https://doi.org/10.1016/j.chemgeo.2023.121698