In the UK, over 150,000m3 of radioactive waste (enough to fill 60 Olympic size swimming pools) has been produced to date. Most of this radioactive waste needs conditioning by encapsulating it in cement to prevent release to the biosphere.
Encapsulants based on Portland cement (PC) blended with supplementary cementitious materials (SCM) such as fly ash (FA) and blast furnace slag (BFS) are essential to cementation of much of the radioactive waste produced in the UK to date. However, with traditional SCM such as fly ash and blast furnace slag becoming increasingly scarce, development of PC/SCM encapsulants produced using abundant and readily available SCM such as limestone, calcined clays, and legacy slags, etc., is critical to ensure security of supply.
There is currently limited information on what parameters of raw materials are critical to reliable application, particularly when these encapsulants are formulated with abundant SCM alternatives such as limestone, calcined clays, and legacy slags, under conditions required on nuclear encapsulation plants.
This proposal investigates the mechanisms of fluid-particle and particle-particle interactions in PC/SCM encapsulants produced using limestone, calcined clays, and legacy slags as more abundant replacements for BFS and PFA,and the effect of this replacement on composition-structure-property relationships, and reaction mechanisms and kinetics.
Through investigating fundamental particle interactions more robust specifications can be developed for precursor powders utilising abundant SCMs, ensuring security of supply.
Based in the Departments of Chemical and Biological Engineering, and Materials Science and 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 be a part of the GREEN CDT (see below), and join the Sustainable Materials at Sheffield and Cements@Sheffield research teams. They will also benefit from industrial supervision by Sellafield Ltd. They will benefit from being a member of a friendly and collegial group with world-leading expertise and facilities.
The Sustainable Materials at Sheffield group (in the Department of Chemical and Biological Engineering) and the Cements@Sheffield group (in the Department of Materials Science & Engineering) are world-leading research teams, located in highly-rated and very successful departments, building from over 100 years of history in cements research at Sheffield. We investigate interesting and important cements and related materials for applications in nuclear and infrastructure sectors, publish our work in the leading journals and conferences in the field, and take great pride in the fact that alumni have gone on to the highest levels of success in both academia and industry. Both the Department of Chemical and Biological Engineering and the Department of Materials Science & Engineering rank among the top in the UK, and have among the highest levels of research income.
The GREEN Centre for Doctoral Training (GREEN CDT) is a consortium of five universities: The University of Manchester, Lancaster University, The University of Leeds, The University of Liverpool and The University of Sheffield, which aims to train the next generation of expert nuclear scientists and engineers.
The four-year PhD programme invites students to attend taught courses (Year 1) in various subjects of nuclear technology followed by subject specific training (Year 1), then progress to the PhD-level research activities described in the Summary (Year 2 - Year 4).
Please see this link for information on how to apply: https://www.sheffield.ac.uk/cbe/postgraduate/phd/how-apply. Please include the name of your proposed supervisor and the title of the PhD project within your application.
This interdisciplinary project spans chemical and materials engineering.
Applicants should have a first or upper second class UK honours degree or equivalent in a related discipline (Chemical/Materials/Environmental/Civil Engineering, Materials/Inorganic Chemistry or Mineralogy/Geochemistry). A strong undergraduate background in chemical/materials engineering, with an interest in driving sustainability is desired. 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.