Regular Article

Radiolysis of bituminized radioactive waste: a comprehensive review

¹ Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PSE-ENV/SPDR/USDR, F-92260 Fontenay-aux-Roses, France
² Institut de Radioprotection et de Sûreté Nucléaire (IRSN), PSN-RES/SCA/LECEV, F-91400 Saclay, France
³ IES, University of Montpellier, CNRS, Montpellier, France

^* e-mail: hanaa.houjeij@irsn.fr

Received: 14 December 2023
Received in final form: 9 February 2024
Accepted: 21 February 2024
Published online: 29 April 2024

Abstract

In the realm of radioactive waste management, the impact of radiolysis on bitumen and bituminized radioactive waste also called bituminized waste product (BWP) is considered one of the most significant factors influencing structural changes and the generation of radiolysis gas bubbles. This review provides a comprehensive overview of several studies that have explored the intricate interaction between radiation and various types of bitumen, to gain a better understanding of how such waste ages when exposed to radiation. While these studies provide insights into the diverse effects of radiolysis on bitumen, they also highlight numerous unanswered questions. The absence of gas bubbles does not necessarily indicate an absence of gas production, leaving further research to be undertaken. The complexities of bitumen radiolysis offer multiple avenues for future investigation, aiming to enhance our understanding and provide comprehensive solutions for bituminous radioactive waste management. Among the studied types of bitumen, blown R85/40 bitumen and straight-run distilled bitumen with a penetration grade of 70/100 stands out due to their widespread use in immobilizing co-precipitated radioactive sludges. These bituminous matrices play an essential role in understanding the broader implications of radiolysis within the context of bituminous waste management. This review underscores the significance of further research into radiolysis and bitumen ageing, emphasizing the need for a more in-depth exploration of these complex phenomena and their implications for the long-term safety and efficacy of repositories and disposal facilities.