Advancing the Thermal Treatment of Radioactive Graphite Waste

Saturn_Nuclear_CDT

There are approximately 100’000 tonnes of irradiated nuclear graphite in the UK that will eventually require suitable disposal. Currently, this waste is destined for geological disposal in an underground facility that has not yet been approved and would cost several billion pounds.

Nuclear Restoration Services (NRS), a wholly owned subsidiary of the UK Nuclear Decommissioning Authority (NDA) has the responsibility to manage this active graphite over the coming decades as part of their commitment to safe and effective decommissioning of UK reactors. NRS will provide access to this material in sufficient quantities to understand whether thermal processing is a viable option for some, or all of this material. Thermal treatment is considered as a potential alternative to geological and previous work in this area has shown it to be an effective method of graphite gasification on a laboratory scale. Additional work has also provided promising results on a pilot scale which showed that ~ 0.5 tonnes of graphite could be converted to CO₂ in a plasma furnace on a reasonable timescale. Ultimately, the chemical and physical parameters involved in large scale graphite oxidation need further investigation so that optimum conditions can be identified which could be scaled up many times, demonstrating that this technology could be viably deployed. In addition to the oxidation parameters several, other factors require further investigation; these include particle size of the graphite, moisture content and catalytic effects as well as how the large quantities of off-gas could be effectively handled and treated.

The hypothesis is that thermal oxidation can be shown to be an effective and suitable treatment strategy for irradiated nuclear graphite waste, that can be readily demonstrated on a smaller laboratory scale, with potential to be upscaled to larger industrial quantities considering secondary waste treatment and handling of off-gases via carbon capture and storage.

The project aims and objectives are as follows:

·      Key aim 1: Optimise thermal treatment parameters using laboratory scale tube furnace on virgin graphite.

·      Key aim 2: Upscale from smaller bench-top experiments (grams) to larger laboratory scale (kilograms).

·      Key Aim 3: Laboratory scale work on active graphite specimens.

·      Key Aim 4: Look towards further upscaling to pilot/industrial scale as viable alternative to geological disposal and perform a cost-analysis to demonstrate economic viability of this disposal route.

Eligibility

Applicants should have, or expect to achieve, at least a 2.1 honours degree or a master’s (or international equivalent) in a relevant science or engineering related discipline.

Before you apply

We strongly recommend that you contact the supervisor(s) for this project before you apply.

Equality, diversity and inclusion

Equality, diversity and inclusion is fundamental to the success of The University of Manchester, and is at the heart of all of our activities. We know that diversity strengthens our research community, leading to enhanced research creativity, productivity and quality, and societal and economic impact.

We actively encourage applicants from diverse career paths and backgrounds and from all sections of the community, regardless of age, disability, ethnicity, gender, gender expression, sexual orientation and transgender status.

We also support applications from those returning from a career break or other roles. We consider offering flexible study arrangements (including part-time: 50%, 60% or 80%, depending on the project/funder).