Field, laboratory and modelling constraints on fluid transport of hydrogen in fractured mudrocks with a focus on chemical self-healing

REF: EGIS2023-AB2

Predicting the retention of hydrogen gas in the subsurface is a cross cutting issue with relevance to energy storage, hydrogen prospecting, and the disposal of radioactive wastes. Underground hydrogen storage (UHS) is a means of storing intermittent energy production from renewable energy sources, and retention of the hydrogen in the geological reservoir is crucial for the economic performance of the store. The geological disposal of radioactive wastes in an underground repository is considered the optimal solution for the UK's waste; hydrogen gas produced by the corrosion of waste containers can impact the stores security through over-pressurization and may act as a pathway for radionuclide migration out-with the repository. The evaluation of hydrogen gas migration in geological structures, including fault-fracture systems, is therefore crucial to assessing the performance of these critical energy industries.

This project will focus on the Mercia Mudrock Group (MMG) which is currently being considered as a potential host rock for GDF and caprock for UHS. Prediction of hydrogen migration (carrying radionuclide) in such geologies is challenged by the complex architecture of fault-fracture systems and mechanical stratigraphy of the interbedded mudrock and evaporites of the MMG, together with the inherent challenges of modelling complex multi-scalar transport phenomena in geological media. Demonstrating an understanding of the fracture hosted (single and two phase) fluid flow and solute transport process will be integral to such assessments. This PhD project will help to reduce uncertainty in the characterisation of fault-fracture systems and fluid flow in the MMG.

This broad scope of this research involves the observational description of MMG fault-fracture systems from outcrops and cores including assessing the mechanical-stratigraphic controls on fracture network geometries, the measurement of single (and multi-phase) flow in fractures as a function of rock-fracture properties, effective stress, and fracture / stress field orientations as well as the measurement of adsorbing solute and fluid specific transport processes. All this information needs to be integrated in model frameworks focusing on flow and transport in fractures or the exchange between fractures and matrix. Given the need for models to describe flow at various length-scales, including regional scales, detailed numerical upscaling workflows are required to derive constitutive relationships and effective properties for radionuclide and gas transport at decametre scales. This specifically requires a strong interplay between observations done in outcrops (fracture network and statistics thereof, understanding of fracture mineralisation versus stress directions etc) and the development of coupled hydro-chemical-mechanical models. This interplay, supported by laboratory data, will be a key output of this project to advance the understanding of fluid flow along fractures and to highlight the potential of multi-scale, multi-method approaches to evaluate the safety case in the MMG.

Industrial Placement

We aim for a placement of at least 3 months at a European Geological Survey (e.g. British Geological Survey) or with energy companies having similar interest in multi-phase fracture flow.

Partners

The project is in close collaboration with Nuclear Waste Services in the UK, which is part of the Nuclear Decommissioning Authority.

Funding

This is a full scholarship which will cover tuition fees for UK-based students and provide an annual stipend in line with EPSRC recommended levels (£18,622 in 2023/24) for the 48 months duration of the project. In addition, the project is generously supported by our partner Nuclear Waste Services to support research and travel expenses.

Eligibility

This scholarship is available to UK students only.

To be eligible, applicants should have a BSc/MSci 2:1 and/or Masters (MSc) at Merit/Distinction level (>60%) and/or evidence of significant relevant professional experience equivalent to Masters level. Applicants with a geomaterials/geochemistry/chemistry/physics/applied geoscience/reservoir engineering related qualification and an interest in field work, geochemical, computational, petrophysical, or geomechanical methods are particularly encouraged. Applicants should further have a strong motivation to succeed in scientific research, excellent presentation, and scientific writing skills as well as very good to excellent English language skills (verbally and written). Scholarships will be awarded by competitive merit, taking into account the academic ability of the applicant. We particularly encourage female candidates as well as candidates from ethnic minorities to apply. The successful candidate will be joining a cohort of about 40-50 PGRs who are roughly 50/50 male/female. Flexibility can be offered if someone has any caring responsibilities

How to apply

To apply you must complete our online application form.

Please select PhD GeoEnergy Engineering as the programme and include the full project title, reference number and supervisor name on your application form. Ensure that all fields marked as 'required' are complete.

Once you have submitted your personal details, you will be asked to upload your supporting documents. You must complete the section marked project proposal; provide a supporting statement (1-2 A4 pages) documenting your reasons for applying to this particular project, outlining your suitability and how you would approach the project. You must also upload your CV, a copy of your degree certificate and relevant transcripts and an academic reference in the relevant section of the application form.

Please contact Prof. Andreas Busch (a.busch@hw.ac.uk), Dr. Niko Kampman (niko.kampman@nuclearwasteservices.uk), Prof. Florian Doster (f.doster@hw.ac.uk) or Dr. Nathaniel Forbes Inskip (n.forbes_inskip@hw.ac.uk) for informal information.

Timeline

The closing date for applications is 16^th June 2023 and applicants must be available to start in September 2023 or January 2024.