Postgraduate research opportunities

Exploiting thermally and microbially induced carbonate precipitation to improve reservoir storage integrity

This project will explore how thermal and microbial hydrolysis of urea can be used to control the precipitation of CaCO3. When correctly controlled this process has the potential to provide an alternative treatment strategy for sealing leakage pathways in CCS/hydrogen wells.

Number of places

1

Funding

Home fee, Stipend

Opens

9 March 2020

Deadline

22 May 2020

Duration

4 years

Eligibility

The project will suit a student with a broad interest in addressing major geoscience questions using experimental, quantitative and numerical methods. You will learn how to use a range of high-level analytical methods (x-ray tomography, image analysis, fluid flow analysis, modelling), and to integrate data types to gain insight from both scientific and industrial perspectives. Funding of tuition fees is at the UK level which currently also applies to EU students but this may change in respect of the later years of study depending on the outcome of Brexit negotiations and the stance adopted by each participating CDT university.  EU and International students are therefore advised to contact the hosting university to check whether additional funding is available to cover the potential difference in fee levels charged to Home and International students before submitting an application.

Project Details

Use of subsurface storage is a key part of the transition towards a low carbon energy system, allowing for both reduction of existing atmospheric CO2 though carbon capture & storage, and implementation of other low carbon contributions to the energy mix including compressed air energy storage (CAES) and hydrogen storage. The critical component of temporary (CAES and H2) or permanent (CO2) storage solutions, is ensuring the geological system (reservoir) and the engineering infrastructure (well casings) are stable under injection and storage conditions. This project will explore how thermal and microbial hydrolysis of urea can be used to control the precipitation of CaCO3. When correctly controlled this process has the potential to provide an alternative treatment strategy for sealing leakage pathways in CCS/hydrogen wells, as well as controlling the compartmentalisation of the reservoir. Within the range of reservoir systems likely to be storage targets, controlling the spatial and temporal distribution of CaCO3 will be critical in proving long term integrity, but could also pay a role in maximising storage capacity. Unwanted precipitation could dramatically reduce storage efficiency, acting as a barrier to flow. The applicant will use novel high pressure and temperature flow-cells (NERC GeoX Suite) that can recreate a range of storage reservoir conditions and track the permeability evolution through time under variable flow and fluid injection scenarios. The flow cells are all X-ray microtomography compatible, allowing simultaneous measurement of microstructure (porosity) and permeability, and real time quantification of the rate and spatial distribution of precipitation under geological conditions in a range of target lithologies. The project will use both laboratory and synchrotron-based tomography during CaCO3 precipitation over a range of spatial and temporal scales, and capture the evolution and migration of preferential flow pathways with the aim of understanding the fundamental principles that govern the reactive-transport, nucleation-precipitation, and hydrodynamic-feedback processes.

Funding Details

Studentships are fully funded for 4 years and cover tuition fees and stipend at the UK Research & Innovation recommended levels for each year of study.  For the 2020/21 academic session, this is £4,327 for fees and £15,009 for stipend.  Studentships also provide a generous £20,000 individual allowance to cover costs associated with pursuing the PhD over the 4-year study period e.g. conference travel, data collection, equipment purchase, travel to and from CDT training courses.  The studentship period is 4 years in order to accommodate the CDT’s bespoke 20-week residential training programme, attendance on which is a condition of acceptance of a funded CDT studentship.