Postdoctoral fellowship available at IRSN
POST DOCTORAL FELLOWSHIP: Investigation of the radiolytic properties of bitumens and synthesized bituminized waste
The IRSN is recruiting a postdoctoral fellow to investigate the radiolytic properties of bitumens and synthesized bituminized waste. The research will be hosted at Fontenay aux Roses, Paris, for 18 months.
Coprecipitation sludges employed in the water treatment of effluent in the nuclear industry are immobilized in bitumen matrix. This mixture is known as bituminized waste, and it consists of long-lived medium and low-level waste. The structure of the bituminized waste will alter during storage due to self-irradiation, and radiolysis gases will occur. Because bituminous mixtures are opaque, direct visual observation of such occurrences is impossible. X-ray tomography is currently used to determine the distribution of radiolysis bubbles inside the bitumen matrix. However, this approach does not allow for a conclusion on the significance of the bubble coalescence phenomena or for direct observation of bubble production and migration in hot bituminized waste between 70 and 110°C (temperature range corresponding to the temperatures of triggering of the first exothermic chemical reactions). To overcome this technological challenge, the ARISE project seeks to investigate the viability of ultrasonic technologies for detecting the emergence of radiolysis bubbles and monitoring them in real time during a temperature rise. The project calls for the validation of this ultrasonic technology tried using X-ray tomography techniques. By overcoming the barrier posed by bitumen opacity, this innovative ultrasonic approach may eventually allow researchers to better understand the aging under irradiation of bituminized waste over several decades of storage and so increase their safety.
They are searching for a candidate with a doctorate in science who specializes in materials and/or sensors and has experience with cell design or radiolysis. Technical abilities in micro-tomography and/or ultrasonic sensors will be required to comprehend the project. Expertise in the design or implementation of experimental techniques is required. For the fellowship, the candidate must be self-sufficient and comfortable working in a group. More information can be found on the job advert here, or email Lucie Millot (email@example.com).