Skip to main content

Modelling of precipitation reactors in the reprocessing of spent nuclear fuel


Key facts

Type of research degree
Application deadline
Monday 15 July 2024
Project start date
Tuesday 1 October 2024
Country eligibility
UK only
Source of funding
Centre for doctoral training
Dr Tariq Mahmud
Additional supervisors
Professor Kevin Roberts
School of Chemical and Process Engineering
<h2 class="heading hide-accessible">Summary</h2>

Nuclear power generation is expected to rise to meet increasing UK and global energy demand, whilst maintaining net-zero targets. In this context, reprocessing of waste from nuclear reactors in order to recover and reuse uranium (U) and plutonium (Pu) will play a critical role in the spent nuclear fuel (SNF) management. The proposed project focuses on the unit operation in SNF reprocessing, which involves precipitation of Pu(IV) oxalate or co-precipitation of U(IV)/Pu(III) oxalate crystals via the reactions between Pu and U nitrates and oxalic acid. The crystal morphology and size distribution influence the efficiency of downstream processing, such as filtration and calcination, and the performance of fuel. The precipitation reactions are performed in a continuous unbaffled vortex reactor agitated with a magnetic stirrer, which was initially developed by the UKAEA in the early 1950&rsquo;s. A detailed understanding of the reactor hydrodynamic and mixing characteristics is needed and how it affects the precipitation process and resulting crystal properties.

<h2 class="heading hide-accessible">Full description</h2>

<p style="text-align:justify; margin-bottom:11px">This PhD project builds on our previous studies on the precipitation of Ca and Ce oxalates as simulants. It aims to address challenges associated with the development and application of digital process modelling tools to investigate the influence of reactor design and processing conditions on the crystal properties. In this project, precipitation process models, based on a population balance model, will be developed for the prediction of crystal size distribution, which will be integrated with a Computational Fluid Dynamics (CFD) software (e.g. ANSYS Fluent) for taking into account the effect of the reactor hydrodynamics and mixing. Experiments will be carried out to collect data as necessay for model development and refinement. The model can be used as an effective tool for providing an improved understanding of the underpinning science of precipitation processes and optimising the reactor design and safe operating conditions to produce crystals with a required size and shape distributions.</p> <p><strong>About&nbsp;SATURN_Nuclear_CDT</strong></p> <p>This project is part of the&nbsp;<a href="">Centre for Doctoral Training (CDT) in SATURN (Skills And Training Underpinning a Renaissance in Nuclear)</a>. It is led from the University of Manchester and includes leading nuclear research universities in the North of England and Scottland (University of Leeds, University of Sheffield, Lancaster University, University of Liverpool, University of Strathclyde). We aim to deliver the next generation of nuclear researchers to help the UK achieve its Net Zero targets and beyond, in a collegial cohort environment. The CDT will also include technical training in the nuclear fuel cycle to ensure all candidates are familiar with the nuclear sector, and specialist research skills training.</p> <p style="text-align:justify; margin-bottom:11px"><strong>References</strong></p> <ol> <li class="MsoBodyText">Mahmud, T., Haque, J. N., Roberts, K. J., Rhodes, D., Wilkinson, D., Measurements and modelling of free-surface turbulent flows induced by a magnetic stirrer in an unbaffled stirred tank reactor. Chemical Engineering Science, 64, 4197-4209, 2009. (<a href=""></a>)</li> <li>Corzo, D. M. C., Ma, C. Y., Mahmud, T. Roberts, K. J., Digital design of batch cooling crystallisation process: CFD methodology for modelling free-surface hydrodynamics in agitated crystallisers. Organic Process Research &amp; Development, 24, 2565-2582, 2020.&nbsp;(<a href="" title="DOI URL"></a>)</li> </ol>

<h2 class="heading">How to apply</h2>

<p>Formal applications for research degree study should be made online through the&nbsp;<a href="">University&#39;s website</a>. Please state clearly in the Planned Course of Study section that you are applying for&nbsp;<em><strong>EPSRC CDT SATURN &ndash;&nbsp;Nuclear Science and Engineering</strong></em>,&nbsp;in the research information section&nbsp;that the research degree you wish to be considered for is&nbsp;<em><strong>Modelling of precipitation reactors in the reprocessing of spent nuclear fuel</strong></em>&nbsp;as well as <a href="">Dr Tariq Mahmud</a>&nbsp;as your proposed supervisor and&nbsp;<em><strong>in the finance section, please state clearly that the funding source you are applying for is EPSRC CDT SATURN.</strong></em></p> <p>If English is not your first language, you must provide evidence that you meet the University&#39;s minimum English language requirements (below).</p> <p><em>As an international research-intensive university, we welcome students from all walks of life and from across the world. We foster an inclusive environment where all can flourish and prosper, and we are proud of our strong commitment to student education. Across all Faculties we are dedicated to diversifying our community and we welcome the unique contributions that individuals can bring, and particularly encourage applications from, but not limited to Black, Asian, people who belong to a minority ethnic community, people who identify as LGBT+ and people with disabilities. Applicants will always be selected based on merit and ability.</em></p> <p>Applications will be considered on an ongoing basis. &nbsp;Potential applicants are strongly encouraged to contact the supervisors for an informal discussion before making a formal application. &nbsp;We also advise that you apply at the earliest opportunity as the application and selection process may close early, should we receive a sufficient number of applications or that a suitable candidate is appointed.</p> <p>Please note that you must provide the following documents in support of your application by the closing date of 15 July 2024:</p> <ul> <li>Full Transcripts of all degree study or if in final year of study, full transcripts to date</li> <li>Personal Statement outlining your interest in the project</li> <li>CV</li> </ul>

<h2 class="heading heading--sm">Entry requirements</h2>

Candidates will have, or be due to obtain, a Master&rsquo;s Degree or equivalent from a reputable university in an appropriate field of Engineering. Exceptional candidates with a First Class Bachelor&rsquo;s Degree in an appropriate field will also be considered. Applicants are advised to check with the relevant School prior to making an application.

<h2 class="heading heading--sm">English language requirements</h2>

The minimum English language entry requirement for research postgraduate research study is an IELTS of 6.0 overall with at least 5.5 in each component (reading, writing, listening and speaking) or equivalent. The test must be dated within two years of the start date of the course in order to be valid. Some schools and faculties have a higher requirement.

<h2 class="heading">Funding on offer</h2>

<p>A highly competitive EPSRC Centre for Doctoral Training in Skills And Training Underpinning a Renaissance in Nuclear (SATURN)&nbsp;studentship, offering the award of fees, together with a tax-free maintenance grant of &pound;19,237 per year for 4&nbsp;years.&nbsp; Training and support will also be provided.<br /> <br /> This opportunity is open to UK applicants only. All candidates will be placed into the EPSRC Centre for Doctoral Training in SATURN Studentship Competition and selection is based on academic merit.<br /> <br /> Please refer to the&nbsp;<a href="">UKCISA</a>&nbsp;website for&nbsp;information regarding Fee Status for Non-UK Nationals.</p>

<h2 class="heading">Contact details</h2>

<p>For further information about this project, please contact Dr Tariq Mahmud by email to&nbsp;<a href=""></a></p> <p>For further information about your application, please contact Doctoral College Admissions by email to&nbsp;<a href=""></a></p> <p>For further information about the CDT SATURN programme, please contact the CDT SATURN Programme Team by email to&nbsp;<a href=""></a>&nbsp;or Dr Timothy Hunter by email to&nbsp;<a href=""></a></p>