Meet the 2022 GREEN CDT Cohort!
Social 31st May 2023
The Growing skills for Reliable Economic Energy from Nuclear (GREEN) CDT is a consortium of 5 universities: Lancaster, Leeds, Liverpool, Manchester and Sheffield. It was formed in 2018 and currently has around 75 PhD students at various points in their studies across the 5 universities.
This page lists some of the 2022 GREEN PhD students that have begun their nuclear research journeys.
Understanding radionuclide behaviour at the plant-soil interface to direct bioremediation strategies for contaminated land
Rachel Drew – email@example.com
Industrial activities, leakage of radiation from nuclear sites, and mining have left a legacy of radionuclide-contaminated ground. This can lead to environmental toxicity and the mobilisation of radionuclides into the food chain. 90Sr and 137Cs, with half-lives of 29.1 and 30.17 years respectively, are two principal medium-lived fission products and remain a significant environmental concern. My PhD project combines plant biology, microbiology, soil geochemistry, and radiochemistry to look at how plants can be used in remediating land contaminated with radionuclides, in a method known as phytoremediation. Some plants, known as hyperaccumulators, can tolerate contaminated ground and accumulate high levels of contaminants and these mechanisms can be exploited to remediate land.
In Situ Gas Analysis for Interim Spent Fuel Containers
Rebecca Clews – Rebecca.Clewsfirstname.lastname@example.org
The UK is currently considering the use of interim dry storage for a large proportion of its spent nuclear fuel inventory pending final disposal in a Geological Disposal Facility (GDF). There is currently no mature monitoring technique for the spent fuel that can withstand penetration, and few options are being considered. This project will explore the use of a combined LIBS and Raman approach to monitor and assess the limit of detection of several gases of interest produced during the dry storage. The project will also consider the integration of the technique into the container design and determine the TRL of the method for deployment.
Developing a Novel High Frequency Resonator Rheometer
Guohong Gao – email@example.com
The retrieval of nuclear waste from legacy facilities and its transfer to long-term storage is a top priority for the UK nuclear industry. Much of the waste is a suspension formed from corroding fuel and fuel cladding. To design a reliable and safe retrieval process requires knowledge of the suspension rheology, a property that describes the flow of a material. Being able to measure the suspension rheology in its storage environment is desirable as it provides a more reliable measurement and eliminates the effect of sample handling and history. Such measurements are currently difficult to make using traditional rheometer techniques, therefore, the current study will explore the development of a new compact rheometer which excites the microstructure of the suspension using high frequency resonance. Using rapid prototyping techniques, the study will develop a new torsional resonator for deployment in realistic industry environments to measure the viscoelasticity and yield stress of nuclear test materials.
Understanding the materials performance of additive manufactured stainless steel components in high temperature water
James Hall – firstname.lastname@example.org
Austenitic stainless steels and Ni base alloys are extensively used in the primary circuit internals of pressurised water reactors (PWR) due to their high corrosion resistance properties. There is a desire to produce near net shape components via additive manufacturing thanks to the reduce machining costs, more agile manufacturing, and shorter lead times compared to historical methods. In this way, the overall aim of my project is to characterise the microstructure of additively manufactured (AM) nickel alloys produced via laser powder bed fusion, and compare the mechanical properties (tensile strength, fracture toughness) and susceptibility to environmentally assisted cracking (EAC) of material in three conditions of interest: forged, AM and heat treated. The secondary aim is to develop an understanding of the processing-microstructure-mechanical property relationships at work, and hence suggest process alterations to optimise material performance.
Flexible Peptide Decorated Polyaminocarboxylate Ligands for Selective Extraction of Radiotherapeutic Metals for Targeted Alpha Cancer Therapy
Cerys Evans – email@example.com
My PhD project is developing selective extractants for therapeutic radionuclides currently disposed of in reactor waste streams. The extractants will be based on peptide-appended polyaminocarboxylate chelators with variable backbone length, donor atoms and amino acid/peptide sequences and will be looking to characterise each extracted species by standard analytical techniques fully. Once a given metal ion has been extracted, (aqueous to organic phase or vice versa depending on the target radionuclide), I will be looking at rapidly bioconjugating the peptide appendages to known proteins/targeting vectors using established chemistry and their suitability for cancer therapy assessed in vitro using fluorescence spectroscopy and microscopy.
Application of Advanced Simulation Tools for Multiphysics Evaluation of the SMR Cores
Abdo Ez Aldeen – firstname.lastname@example.org
Small modular reactors (SMRs) are an attractive alternative to modern large-scale nuclear power plants due to the advantages they offer, such as shorter deployment time, smaller capital costs, and the ability to be sited in remote locations. SMRs vary in power from tens to hundreds of MWs and can be used for electricity generation, heating, water desalination and other industrial tasks. This PhD project aims to continue the development of SMRs with the support of industrial partners. A key point will be to identify the challenges in modelling and simulating the SMRs (both boron and boron-free) when compared to traditional large-scale reactors. This will enable the discovery of efficient methods to accurately study the sensitivity of operational parameters using simulations. A combination of advanced modelling and simulation tools will be used, such as the full core simulator DYN3D, the neutron transport solver LOTUS, and the subchannel thermal-hydraulics code CTF. The project will allow identification paths for accurate modelling and simulation of the SMR cores without the computationally expensive full-core pin-by-pin simulations. This approach will be attractive for industrial application of the developed methodology.
Novel Approaches to Lithium Isotope Enrichment to Support the Development of Nuclear Fusion Reactors
Jacob Russell – Jacob.email@example.com
Given the increasing development of nuclear fusion in the UK as an increasingly manifesting part of green energy, questions must be asked on how it will all work. Beyond the materials needed to make the reactor the, in my humble opinion, most important question of fuel must be answered. For the purposes of my project the fuel for the reactions is a combination of deuterium and tritium, and I will be focusing on the tritium. Tritium as a radioactive gas is very difficult to handle therefore the community has moved towards breeder sources, this being Lithium-6. The isotope is at 7.5% abundance naturally, so enrichment is required, and this is what my project focuses on. I will be using the subtly different sizes of the isotopes to preferentially extract the preferred isotope with solvent extraction and macrocycles and further developing this beyond a benchtop system to potentially a viable industrial extraction system. Further to this research, I will be undertaking additional research into potential isotopic detection systems utilising NMR and LIBS techniques.
Geological Fate and Impact of Isosaccharinic Acid
Rebecca Snow – firstname.lastname@example.org
Low-heat-generating, cellulose-containing wastes that are produced from the operation and decommissioning of nuclear activities will be disposed of in a geological disposal facility (GDF) deep underground. The chemical degradation of cellulose under the alkaline conditions expected in the GDF over long timescales leads to the production of isosaccharinic acid (ISA). ISA has the potential to enhance radionuclide mobility, requiring its consideration in performance assessments, however, microorganisms living deep underground may degrade ISA, thus limiting its effect as a radionuclide complexant.
This project will fill gaps in our current knowledge of microbial ISA metabolism in a GDF system, to underpin the evolving safety case. We will use advanced analytical and imaging tools, in combination with the latest innovations in DNA sequencing to quantify these processes in laboratory experiments, and determine their impact on radionuclide mobility.
Optimal cutting, grasping and packing of irregular-shaped to tokamak waste components
Yifu Wei – email@example.com
Future fusion devices such as ITER and DEMO will produce high-energy neutron radiation as part of their normal operation. This radiation will be contained inside the plasma vessel. Every few years, regular maintenance work will involve the removal and replacement of many types of components, for example tokamak wall segments damaged by the neutron radiation. The neutrons also activate the components, causing them to emit gamma-radiation for many years. As a consequence, these irregularly-shaped radioactive components will need to be stored for several decades in order to allow the radiation to decay away before final disposal and/or recycling. In order to minimise costs by facilitating more efficient transportation and storage, these components will need to be cut up and packed into containers in the fastest, safest and most space-efficient way possible. Due to the safety hazards arising from handling nuclear components, the solution to this challenge will involve robotic cutting, grasping, and packing of these components. This work will need to be done as quickly as possible and with minimal human supervision in order to reduce costs.