Postgraduate research opportunities

Effect of high temperatures on cement backfill (NRVB) – Improving the safety case for deep geological disposal of radioactive waste.

This project focuses on understanding the long term chemical alteration and stability of a cement (NRVB) backfill material used in GDF, at the temperatures reached in the facility. This is important to improving and developing the safety case for deep geological disposal of radioactive waste.

Number of places

1

Funding

Home fee, Equipment costs, Travel costs, Stipend

Opens

6 April 2021

Deadline

30 June 2021

Duration

48 months

Eligibility

We are looking for a highly motivated person to undertake multi-disciplinary research. Applicants should have an excellent undergraduate degree (MSc/MEng/BSc/BEng) in Chemistry/Chemical Engineering/Materials, Science/Physics, or related subjects, and be comfortable working in chemistry and engineering laboratories. Any previous experience using Matlab or similar is advantageous but not a pre-requisite. This is 1 of 2 studentships funded by RWM on long term cement behavior at Strathclyde University. Both studentships have to begin by October 2021 and provide an opportunity for collaborative working between the 2 successful applicants.

The studentship is available for a student from the United Kingdom or from the European Union (with settled or pre-settled status).

If English is not your first language you will require a valid English certificate equivalent to IELTS 6.5+ overall with a minimum score of 6.0 in Writing and 5.5 in all sections (Reading, Listening, Speaking).

UKRI Studentship Eligibility

The eligibility criteria for UKRI funding has changed for studentships commencing in the 2021/22 academic year. Now, all home and international students are eligible to apply for UKRI funding which will cover the full stipend and tuition fees at the home rate (not the international rate). Under the new criteria, UKRI have stipulated a maximum percentage of international students that can be recruited each year against individual training grants. This will be managed at the institutional level for all EPSRC DTP and ICASE grants. For EPSRC CDT grants, this will be managed by the individual CDT administrative/management team. For ESRC and AHRC studentships the final funding decision will be made by the respective grant holder.

 

To be classed as a home student, applicants must meet the following criteria:

  • Be a UK national (meeting residency requirements), or
  • Have settled status, or
  • Have pre-settled status (meeting residency requirements), or
  • Have indefinite leave to remain or enter.

 

The residency requirements are based on the Education (Fees and Awards) (England) Regulations 2007 and subsequent amendments. Normally to be eligible for a full award a student must have no restrictions on how long they can stay in the UK and have been ordinarily resident in the UK for at least 3 years prior to the start of the studentship (with some further constraint regarding residence for education).

If a student does not meet the criteria above, they will be classed as an international student. The international portion of the tuition fee cannot be funded by the UKRI grant and must be covered from other sources. International students are permitted to self-fund the difference between the home and international fee rates.

Project Details

Nuclear energy provides almost a fifth of the UK’s electricity, generating waste that needs to be managed for safe, long term storage. While most of this waste comes from the generation of electricity, it is also a by-product of many medical and industrial processes, research and defense activities that make use of radioactivity and radioactive materials. In a Geological Disposal Facility (GDF), higher-activity waste is stored hundreds of metres deep underground and GDF is internationally recognised as the safest long-term solution for this type of waste. This project focuses on understanding the long term chemical alteration and stability of a cement (NRVB) backfill material used in GDF, at the temperatures reached in the facility. This is important to improving and developing the safety case for deep geological disposal of radioactive waste. The information available on performance of NRVB under sustained exposure to elevated temperatures above 100 oC is very limited and deals largely with mechanical and thermal properties. The aim of this project is to understand the mineralogy and permeability evolution of hydrothermally cured NRVB at T=100-150 oC from 1 day to 1 year. Nanoparticulate calcium (aluminium) silicate hydrates (C-S-H/C-A-S-H), the primary hydration products of NRVB cement, can convert to more crystalline phases such as tobermorite, hillebrandite and afwillite during heating, which involves crystallographic restructuring, altering the micro-structure and affecting fluid flow paths. While some experimental studies exist on hydrothermally cured oilwell cements, the extent and implications of these recrystallisation/restructuring processes are largely unknown/unexplored for NRVB. The results from this project will aid further (future) work on radionuclide retention and reactive transport in NRVB, which requires a thorough understanding of mineralogy (and porosity/permeability) to support numerical/predictive models on radionuclide retention. Funded by Radioactive Waste Management, this project will directly inform on improving and developing the safety case for deep geological disposal of radioactive waste.

The successful candidate will be trained in and use techniques such as micro-(X-ray diffraction), electron probe micro-analysis, X-ray computed tomography and access national facilities such as Diamond Light Source, to determine how mineralogy, micro-strain, porosity and permeability of NRVB alter hydrothermally. The candidate has a unique opportunity to gain some industrial experience at Radioactive Waste Management (Oxfordshire) to understand their working environment first hand and make an impact on an important problem, while learning high-level and cutting-edge scientific techniques at Strathclyde. The student will be based in the Faculty of Engineering, one of the largest and most successful engineering faculties in the UK, and the largest in Scotland. The student will be supervised by an interdisciplinary team, including Drs Andrea Hamilton, Pieter Bots and Kate Dobson in Civil and Environmental Engineering (CEE) and Dr Paul Edwards in the Physics Department.

Funding Details

This project is fully funded 4 year PhD studentship. The funding covers the cost of tuition fees and provides an annual tax-free stipend for 4 years at the standard UK research rate (£15,667 in 2021/22). A generous allowance is available for accessing instrument facilities and travel/conference attendance. The applicant is required to start by October 2021.

The studentship is available for a student from the United Kingdom or from the European Union (with settled or pre-settled status).

If English is not your first language you will require a valid English certificate equivalent to IELTS 6.5+ overall with a minimum score of 6.0 in Writing and 5.5 in all sections (Reading, Listening, Speaking).

Outstanding applicants that do not meet the above eligibility criteria may be eligible for full fees and a partial stipend, please contact Dr Hamilton.