Saturn_Nuclear_CDT
Nuclear power provides 20% of UK energy demand, and is central to UK Energy Security and Net Zero policies, however, it also generates significant amounts of radioactive waste. Legacy, current, and planned UK nuclear facilities will generate 450,000 m3 of radioactive waste by the end of the century - enough to fill Wembley Stadium. Most of this radioactive waste needs conditioning by encapsulating it in cement to prevent release to the environment.
Blended cements incorporating calcined clays (LC3 encapsulants) are considered the next major step for bulk cement supply within the cement industry along their roadmap towards ‘Net Zero’ and therefore highly likely to become part of the nuclear industries toolbox for waste encapsulation.
However, chemical differences between Portland-limestone calcined clay cement (LC3) encapsulants and Portland cement (PC) encapsulants, and variability in powder physical/chemical characteristics, lead to different physical and chemical characteristics and physical properties, due to extensive differences between aqueous and solid-state chemistry in each case. Little is known about which raw materials are most suitable, and there is little information on what parameters are critical to reliable application.
This PhD examines fluid-particle and particle-particle interactions in LC3 encapsulants produced from a suite of high and low-grade precursor powders, benchmarked against common PC-based encapsulants. It adopts a new in-situ characterisation approach (including surface-specific techniques, spectroscopic and microstructural characterisation) to investigate mechanisms and kinetics of fluid-particle and particle-particle interactions, and effects on performance.
We will study and reveal the fundamental processes controlling dispersion, fluidisation and reaction of these cements, and design, produce and test novel encapsulant formulations with enhanced performance.
This will allow us to develop next-generation low-carbon cement wasteforms for safe disposal of radioactive waste that will help to protect the wellbeing of society and the environment, and enable clean nuclear energy production.
Based in the School of Chemical, Materials, and Biological Engineering, the successful candidate will be joining a team of multidisciplinary researchers at The University of Sheffield to develop research and innovation for decarbonisation. The successful applicant will join the Sustainable Materials at Sheffield research team. They will also benefit from industrial supervision by Sellafield Ltd, and be part of a comprehensive doctoral training programme in this area at The University of Sheffield, led by the primary supervisor Dr Brant Walkley, in collaboration with Sellafield Ltd. and National Nuclear Laboratory, and the Nuclear Decommissioning Authority, that comprises >20 current PhDs in encapsulant/wasteform development across the Faculty of Engineering.
The PhD researcher will also have the opportunity to undertake a 3 to 6-month secondment in with Sellafield Ltd at their R&D site for cement research. During this industrial secondment, the PhD researcher will evaluate research findings to date as relevant to Sellafield Ltd.’s cement-focused business needs.
Eligibility:
Applicants should have a minimum of an upper second class honours degree in chemical engineering, chemistry, bioscience or a related technical subject. If English is not your first language then you must have an International English Language Testing System (IELTS) average of 6.5 or above with at least 6.0 in each component, or equivalent. Please see this link for further information: https://www.sheffield.ac.uk/postgraduate/phd/apply/english-language.
How to apply:
Please complete the enquiry form to express your interest.
We strongly recommend you contact the project supervisor after completing the form to speak to them about your suitability and interest for the project: b.walkley@sheffield.ac.uk
If your qualifications meet our standard entry requirements, the CDT Admissions Team will send your enquiry form and CV to the named project supervisor.
Our application process can also be found on our website: Apply | EPSRC Centre for Doctoral Training in Skills And Training Underpinning a Renaissance in Nuclear | The University of Manchester. If you have any questions, please contact SATURN@manchester.ac.uk
