Autoclaves used in radiolysis experiments
​Autoclaves used in radiolysis experiments

The safety of nuclear fuel repositories

​Lovisa Bauhn, at the Department of Chemistry and Chemical Engineering, recently defended her thesis related to the final repository of used nuclear fuel.

​Could you please tell us a little bit about your research and your results?

According to the KBS-3 method, the used fuel will be placed in copper canisters at a depth of 500 metres in the bedrock, where it should be isolated from contact with groundwater. However, scenarios of groundwater intrusion into the canisters are investigated as part of the safety assessment. In such a scenario, migration of radiotoxic elements into the environment depends on the dissolution behaviour of the UO2 matrix, which could be altered by oxidative species formed during radiolysis of the water. Previous studies have shown that hydrogen gas (which would be formed through anoxic corrosion of canister iron in case of groundwater contact) inhibits the radiation induced oxidative dissolution of the fuel. My research has therefore been focused on further investigations of this hydrogen effect. The results show that the fuel surface itself has an important role in activating the hydrogen, and that the hydrogen effect can be maintained even at very high levels of alpha activity.

What can your results be used for?

The results can be used to provide further understanding of the dissolution behaviour of used nuclear fuel under repository conditions, and they are positive in the sense that they confirm the limited possibility of radionuclide migration with groundwater.

Can you see your results put into action in the future?

Yes, they can be taken into consideration in future repository research and safety assessments.

What are you doing now after becoming PhD?

I am currently working as a researcher at Industrial Materials Recycling at Chalmers.


Published: Mon 04 Dec 2017.